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Publisher: Elsevier   (Total: 3181 journals)

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Showing 1 - 200 of 3181 Journals sorted alphabetically
Academic Pediatrics     Hybrid Journal   (Followers: 39, SJR: 1.655, CiteScore: 2)
Academic Radiology     Hybrid Journal   (Followers: 26, SJR: 1.015, CiteScore: 2)
Accident Analysis & Prevention     Partially Free   (Followers: 105, SJR: 1.462, CiteScore: 3)
Accounting Forum     Hybrid Journal   (Followers: 28, SJR: 0.932, CiteScore: 2)
Accounting, Organizations and Society     Hybrid Journal   (Followers: 42, SJR: 1.771, CiteScore: 3)
Achievements in the Life Sciences     Open Access   (Followers: 7)
Acta Anaesthesiologica Taiwanica     Open Access   (Followers: 6)
Acta Astronautica     Hybrid Journal   (Followers: 442, SJR: 0.758, CiteScore: 2)
Acta Automatica Sinica     Full-text available via subscription   (Followers: 2)
Acta Biomaterialia     Hybrid Journal   (Followers: 29, SJR: 1.967, CiteScore: 7)
Acta Colombiana de Cuidado Intensivo     Full-text available via subscription   (Followers: 3)
Acta de Investigación Psicológica     Open Access   (Followers: 3)
Acta Ecologica Sinica     Open Access   (Followers: 11, SJR: 0.18, CiteScore: 1)
Acta Histochemica     Hybrid Journal   (Followers: 5, SJR: 0.661, CiteScore: 2)
Acta Materialia     Hybrid Journal   (Followers: 319, SJR: 3.263, CiteScore: 6)
Acta Mathematica Scientia     Full-text available via subscription   (Followers: 5, SJR: 0.504, CiteScore: 1)
Acta Mechanica Solida Sinica     Full-text available via subscription   (Followers: 9, SJR: 0.542, CiteScore: 1)
Acta Oecologica     Hybrid Journal   (Followers: 12, SJR: 0.834, CiteScore: 2)
Acta Otorrinolaringologica (English Edition)     Full-text available via subscription  
Acta Otorrinolaringológica Española     Full-text available via subscription   (Followers: 2, SJR: 0.307, CiteScore: 0)
Acta Pharmaceutica Sinica B     Open Access   (Followers: 2, SJR: 1.793, CiteScore: 6)
Acta Poética     Open Access   (Followers: 4, SJR: 0.101, CiteScore: 0)
Acta Psychologica     Hybrid Journal   (Followers: 26, SJR: 1.331, CiteScore: 2)
Acta Sociológica     Open Access   (Followers: 1)
Acta Tropica     Hybrid Journal   (Followers: 6, SJR: 1.052, CiteScore: 2)
Acta Urológica Portuguesa     Open Access  
Actas Dermo-Sifiliograficas     Full-text available via subscription   (Followers: 3, SJR: 0.374, CiteScore: 1)
Actas Dermo-Sifiliográficas (English Edition)     Full-text available via subscription   (Followers: 2)
Actas Urológicas Españolas     Full-text available via subscription   (Followers: 3, SJR: 0.344, CiteScore: 1)
Actas Urológicas Españolas (English Edition)     Full-text available via subscription   (Followers: 1)
Actualites Pharmaceutiques     Full-text available via subscription   (Followers: 7, SJR: 0.19, CiteScore: 0)
Actualites Pharmaceutiques Hospitalieres     Full-text available via subscription   (Followers: 3)
Acupuncture and Related Therapies     Hybrid Journal   (Followers: 8)
Acute Pain     Full-text available via subscription   (Followers: 15, SJR: 2.671, CiteScore: 5)
Ad Hoc Networks     Hybrid Journal   (Followers: 11, SJR: 0.53, CiteScore: 4)
Addictive Behaviors     Hybrid Journal   (Followers: 18, SJR: 1.29, CiteScore: 3)
Addictive Behaviors Reports     Open Access   (Followers: 9, SJR: 0.755, CiteScore: 2)
Additive Manufacturing     Hybrid Journal   (Followers: 11, SJR: 2.611, CiteScore: 8)
Additives for Polymers     Full-text available via subscription   (Followers: 23)
Advanced Drug Delivery Reviews     Hybrid Journal   (Followers: 187, SJR: 4.09, CiteScore: 13)
Advanced Engineering Informatics     Hybrid Journal   (Followers: 12, SJR: 1.167, CiteScore: 4)
Advanced Powder Technology     Hybrid Journal   (Followers: 17, SJR: 0.694, CiteScore: 3)
Advances in Accounting     Hybrid Journal   (Followers: 9, SJR: 0.277, CiteScore: 1)
Advances in Agronomy     Full-text available via subscription   (Followers: 17, SJR: 2.384, CiteScore: 5)
Advances in Anesthesia     Full-text available via subscription   (Followers: 30, SJR: 0.126, CiteScore: 0)
Advances in Antiviral Drug Design     Full-text available via subscription   (Followers: 2)
Advances in Applied Mathematics     Full-text available via subscription   (Followers: 12, SJR: 0.992, CiteScore: 1)
Advances in Applied Mechanics     Full-text available via subscription   (Followers: 12, SJR: 1.551, CiteScore: 4)
Advances in Applied Microbiology     Full-text available via subscription   (Followers: 24, SJR: 2.089, CiteScore: 5)
Advances In Atomic, Molecular, and Optical Physics     Full-text available via subscription   (Followers: 15, SJR: 0.572, CiteScore: 2)
Advances in Biological Regulation     Hybrid Journal   (Followers: 4, SJR: 2.61, CiteScore: 7)
Advances in Botanical Research     Full-text available via subscription   (Followers: 2, SJR: 0.686, CiteScore: 2)
Advances in Cancer Research     Full-text available via subscription   (Followers: 34, SJR: 3.043, CiteScore: 6)
Advances in Carbohydrate Chemistry and Biochemistry     Full-text available via subscription   (Followers: 9, SJR: 1.453, CiteScore: 2)
Advances in Catalysis     Full-text available via subscription   (Followers: 5, SJR: 1.992, CiteScore: 5)
Advances in Cell Aging and Gerontology     Full-text available via subscription   (Followers: 5)
Advances in Cellular and Molecular Biology of Membranes and Organelles     Full-text available via subscription   (Followers: 14)
Advances in Chemical Engineering     Full-text available via subscription   (Followers: 29, SJR: 0.156, CiteScore: 1)
Advances in Child Development and Behavior     Full-text available via subscription   (Followers: 11, SJR: 0.713, CiteScore: 1)
Advances in Chronic Kidney Disease     Full-text available via subscription   (Followers: 10, SJR: 1.316, CiteScore: 2)
Advances in Clinical Chemistry     Full-text available via subscription   (Followers: 26, SJR: 1.562, CiteScore: 3)
Advances in Colloid and Interface Science     Full-text available via subscription   (Followers: 20, SJR: 1.977, CiteScore: 8)
Advances in Computers     Full-text available via subscription   (Followers: 14, SJR: 0.205, CiteScore: 1)
Advances in Dermatology     Full-text available via subscription   (Followers: 15)
Advances in Developmental Biology     Full-text available via subscription   (Followers: 13)
Advances in Digestive Medicine     Open Access   (Followers: 12)
Advances in DNA Sequence-Specific Agents     Full-text available via subscription   (Followers: 7)
Advances in Drug Research     Full-text available via subscription   (Followers: 26)
Advances in Ecological Research     Full-text available via subscription   (Followers: 44, SJR: 2.524, CiteScore: 4)
Advances in Engineering Software     Hybrid Journal   (Followers: 29, SJR: 1.159, CiteScore: 4)
Advances in Experimental Biology     Full-text available via subscription   (Followers: 8)
Advances in Experimental Social Psychology     Full-text available via subscription   (Followers: 52, SJR: 5.39, CiteScore: 8)
Advances in Exploration Geophysics     Full-text available via subscription   (Followers: 1)
Advances in Fluorine Science     Full-text available via subscription   (Followers: 9)
Advances in Food and Nutrition Research     Full-text available via subscription   (Followers: 67, SJR: 0.591, CiteScore: 2)
Advances in Fuel Cells     Full-text available via subscription   (Followers: 17)
Advances in Genetics     Full-text available via subscription   (Followers: 21, SJR: 1.354, CiteScore: 4)
Advances in Genome Biology     Full-text available via subscription   (Followers: 11, SJR: 12.74, CiteScore: 13)
Advances in Geophysics     Full-text available via subscription   (Followers: 7, SJR: 1.193, CiteScore: 3)
Advances in Heat Transfer     Full-text available via subscription   (Followers: 26, SJR: 0.368, CiteScore: 1)
Advances in Heterocyclic Chemistry     Full-text available via subscription   (Followers: 11, SJR: 0.749, CiteScore: 3)
Advances in Human Factors/Ergonomics     Full-text available via subscription   (Followers: 26)
Advances in Imaging and Electron Physics     Full-text available via subscription   (Followers: 3, SJR: 0.193, CiteScore: 0)
Advances in Immunology     Full-text available via subscription   (Followers: 37, SJR: 4.433, CiteScore: 6)
Advances in Inorganic Chemistry     Full-text available via subscription   (Followers: 10, SJR: 1.163, CiteScore: 2)
Advances in Insect Physiology     Full-text available via subscription   (Followers: 2, SJR: 1.938, CiteScore: 3)
Advances in Integrative Medicine     Hybrid Journal   (Followers: 6, SJR: 0.176, CiteScore: 0)
Advances in Intl. Accounting     Full-text available via subscription   (Followers: 3)
Advances in Life Course Research     Hybrid Journal   (Followers: 9, SJR: 0.682, CiteScore: 2)
Advances in Lipobiology     Full-text available via subscription   (Followers: 1)
Advances in Magnetic and Optical Resonance     Full-text available via subscription   (Followers: 8)
Advances in Marine Biology     Full-text available via subscription   (Followers: 21, SJR: 0.88, CiteScore: 2)
Advances in Mathematics     Full-text available via subscription   (Followers: 15, SJR: 3.027, CiteScore: 2)
Advances in Medical Sciences     Hybrid Journal   (Followers: 8, SJR: 0.694, CiteScore: 2)
Advances in Medicinal Chemistry     Full-text available via subscription   (Followers: 6)
Advances in Microbial Physiology     Full-text available via subscription   (Followers: 5, SJR: 1.158, CiteScore: 3)
Advances in Molecular and Cell Biology     Full-text available via subscription   (Followers: 25)
Advances in Molecular and Cellular Endocrinology     Full-text available via subscription   (Followers: 8)
Advances in Molecular Toxicology     Full-text available via subscription   (Followers: 7, SJR: 0.182, CiteScore: 0)
Advances in Nanoporous Materials     Full-text available via subscription   (Followers: 5)
Advances in Oncobiology     Full-text available via subscription   (Followers: 2)
Advances in Organ Biology     Full-text available via subscription   (Followers: 2)
Advances in Organometallic Chemistry     Full-text available via subscription   (Followers: 18, SJR: 1.875, CiteScore: 4)
Advances in Parallel Computing     Full-text available via subscription   (Followers: 7, SJR: 0.174, CiteScore: 0)
Advances in Parasitology     Full-text available via subscription   (Followers: 5, SJR: 1.579, CiteScore: 4)
Advances in Pediatrics     Full-text available via subscription   (Followers: 27, SJR: 0.461, CiteScore: 1)
Advances in Pharmaceutical Sciences     Full-text available via subscription   (Followers: 19)
Advances in Pharmacology     Full-text available via subscription   (Followers: 17, SJR: 1.536, CiteScore: 3)
Advances in Physical Organic Chemistry     Full-text available via subscription   (Followers: 9, SJR: 0.574, CiteScore: 1)
Advances in Phytomedicine     Full-text available via subscription  
Advances in Planar Lipid Bilayers and Liposomes     Full-text available via subscription   (Followers: 3, SJR: 0.109, CiteScore: 1)
Advances in Plant Biochemistry and Molecular Biology     Full-text available via subscription   (Followers: 10)
Advances in Plant Pathology     Full-text available via subscription   (Followers: 6)
Advances in Porous Media     Full-text available via subscription   (Followers: 5)
Advances in Protein Chemistry     Full-text available via subscription   (Followers: 19)
Advances in Protein Chemistry and Structural Biology     Full-text available via subscription   (Followers: 20, SJR: 0.791, CiteScore: 2)
Advances in Psychology     Full-text available via subscription   (Followers: 68)
Advances in Quantum Chemistry     Full-text available via subscription   (Followers: 6, SJR: 0.371, CiteScore: 1)
Advances in Radiation Oncology     Open Access   (Followers: 2, SJR: 0.263, CiteScore: 1)
Advances in Small Animal Medicine and Surgery     Hybrid Journal   (Followers: 3, SJR: 0.101, CiteScore: 0)
Advances in Space Biology and Medicine     Full-text available via subscription   (Followers: 6)
Advances in Space Research     Full-text available via subscription   (Followers: 423, SJR: 0.569, CiteScore: 2)
Advances in Structural Biology     Full-text available via subscription   (Followers: 5)
Advances in Surgery     Full-text available via subscription   (Followers: 13, SJR: 0.555, CiteScore: 2)
Advances in the Study of Behavior     Full-text available via subscription   (Followers: 38, SJR: 2.208, CiteScore: 4)
Advances in Veterinary Medicine     Full-text available via subscription   (Followers: 20)
Advances in Veterinary Science and Comparative Medicine     Full-text available via subscription   (Followers: 15)
Advances in Virus Research     Full-text available via subscription   (Followers: 6, SJR: 2.262, CiteScore: 5)
Advances in Water Resources     Hybrid Journal   (Followers: 54, SJR: 1.551, CiteScore: 3)
Aeolian Research     Hybrid Journal   (Followers: 6, SJR: 1.117, CiteScore: 3)
Aerospace Science and Technology     Hybrid Journal   (Followers: 384, SJR: 0.796, CiteScore: 3)
AEU - Intl. J. of Electronics and Communications     Hybrid Journal   (Followers: 8, SJR: 0.42, CiteScore: 2)
African J. of Emergency Medicine     Open Access   (Followers: 6, SJR: 0.296, CiteScore: 0)
Ageing Research Reviews     Hybrid Journal   (Followers: 12, SJR: 3.671, CiteScore: 9)
Aggression and Violent Behavior     Hybrid Journal   (Followers: 482, SJR: 1.238, CiteScore: 3)
Agri Gene     Hybrid Journal   (Followers: 1, SJR: 0.13, CiteScore: 0)
Agricultural and Forest Meteorology     Hybrid Journal   (Followers: 18, SJR: 1.818, CiteScore: 5)
Agricultural Systems     Hybrid Journal   (Followers: 32, SJR: 1.156, CiteScore: 4)
Agricultural Water Management     Hybrid Journal   (Followers: 45, SJR: 1.272, CiteScore: 3)
Agriculture and Agricultural Science Procedia     Open Access   (Followers: 4)
Agriculture and Natural Resources     Open Access   (Followers: 3)
Agriculture, Ecosystems & Environment     Hybrid Journal   (Followers: 58, SJR: 1.747, CiteScore: 4)
Ain Shams Engineering J.     Open Access   (Followers: 5, SJR: 0.589, CiteScore: 3)
Air Medical J.     Hybrid Journal   (Followers: 8, SJR: 0.26, CiteScore: 0)
AKCE Intl. J. of Graphs and Combinatorics     Open Access   (SJR: 0.19, CiteScore: 0)
Alcohol     Hybrid Journal   (Followers: 12, SJR: 1.153, CiteScore: 3)
Alcoholism and Drug Addiction     Open Access   (Followers: 12)
Alergologia Polska : Polish J. of Allergology     Full-text available via subscription   (Followers: 1)
Alexandria Engineering J.     Open Access   (Followers: 2, SJR: 0.604, CiteScore: 3)
Alexandria J. of Medicine     Open Access   (Followers: 1, SJR: 0.191, CiteScore: 1)
Algal Research     Partially Free   (Followers: 11, SJR: 1.142, CiteScore: 4)
Alkaloids: Chemical and Biological Perspectives     Full-text available via subscription   (Followers: 2)
Allergologia et Immunopathologia     Full-text available via subscription   (Followers: 1, SJR: 0.504, CiteScore: 1)
Allergology Intl.     Open Access   (Followers: 5, SJR: 1.148, CiteScore: 2)
Alpha Omegan     Full-text available via subscription   (SJR: 3.521, CiteScore: 6)
ALTER - European J. of Disability Research / Revue Européenne de Recherche sur le Handicap     Full-text available via subscription   (Followers: 11, SJR: 0.201, CiteScore: 1)
Alzheimer's & Dementia     Hybrid Journal   (Followers: 54, SJR: 4.66, CiteScore: 10)
Alzheimer's & Dementia: Diagnosis, Assessment & Disease Monitoring     Open Access   (Followers: 6, SJR: 1.796, CiteScore: 4)
Alzheimer's & Dementia: Translational Research & Clinical Interventions     Open Access   (Followers: 6, SJR: 1.108, CiteScore: 3)
Ambulatory Pediatrics     Hybrid Journal   (Followers: 5)
American Heart J.     Hybrid Journal   (Followers: 58, SJR: 3.267, CiteScore: 4)
American J. of Cardiology     Hybrid Journal   (Followers: 66, SJR: 1.93, CiteScore: 3)
American J. of Emergency Medicine     Hybrid Journal   (Followers: 47, SJR: 0.604, CiteScore: 1)
American J. of Geriatric Pharmacotherapy     Full-text available via subscription   (Followers: 13)
American J. of Geriatric Psychiatry     Hybrid Journal   (Followers: 14, SJR: 1.524, CiteScore: 3)
American J. of Human Genetics     Hybrid Journal   (Followers: 37, SJR: 7.45, CiteScore: 8)
American J. of Infection Control     Hybrid Journal   (Followers: 29, SJR: 1.062, CiteScore: 2)
American J. of Kidney Diseases     Hybrid Journal   (Followers: 36, SJR: 2.973, CiteScore: 4)
American J. of Medicine     Hybrid Journal   (Followers: 50)
American J. of Medicine Supplements     Full-text available via subscription   (Followers: 3, SJR: 1.967, CiteScore: 2)
American J. of Obstetrics and Gynecology     Hybrid Journal   (Followers: 265, SJR: 2.7, CiteScore: 4)
American J. of Ophthalmology     Hybrid Journal   (Followers: 66, SJR: 3.184, CiteScore: 4)
American J. of Ophthalmology Case Reports     Open Access   (Followers: 5, SJR: 0.265, CiteScore: 0)
American J. of Orthodontics and Dentofacial Orthopedics     Full-text available via subscription   (Followers: 6, SJR: 1.289, CiteScore: 1)
American J. of Otolaryngology     Hybrid Journal   (Followers: 25, SJR: 0.59, CiteScore: 1)
American J. of Pathology     Hybrid Journal   (Followers: 32, SJR: 2.139, CiteScore: 4)
American J. of Preventive Medicine     Hybrid Journal   (Followers: 28, SJR: 2.164, CiteScore: 4)
American J. of Surgery     Hybrid Journal   (Followers: 39, SJR: 1.141, CiteScore: 2)
American J. of the Medical Sciences     Hybrid Journal   (Followers: 12, SJR: 0.767, CiteScore: 1)
Ampersand : An Intl. J. of General and Applied Linguistics     Open Access   (Followers: 7)
Anaerobe     Hybrid Journal   (Followers: 4, SJR: 1.144, CiteScore: 3)
Anaesthesia & Intensive Care Medicine     Full-text available via subscription   (Followers: 67, SJR: 0.138, CiteScore: 0)
Anaesthesia Critical Care & Pain Medicine     Full-text available via subscription   (Followers: 25, SJR: 0.411, CiteScore: 1)
Anales de Cirugia Vascular     Full-text available via subscription   (Followers: 1)
Anales de Pediatría     Full-text available via subscription   (Followers: 3, SJR: 0.277, CiteScore: 0)
Anales de Pediatría (English Edition)     Full-text available via subscription  
Anales de Pediatría Continuada     Full-text available via subscription  
Analytic Methods in Accident Research     Hybrid Journal   (Followers: 5, SJR: 4.849, CiteScore: 10)
Analytica Chimica Acta     Hybrid Journal   (Followers: 44, SJR: 1.512, CiteScore: 5)
Analytica Chimica Acta : X     Open Access  
Analytical Biochemistry     Hybrid Journal   (Followers: 210, SJR: 0.633, CiteScore: 2)
Analytical Chemistry Research     Open Access   (Followers: 13, SJR: 0.411, CiteScore: 2)
Analytical Spectroscopy Library     Full-text available via subscription   (Followers: 14)
Anesthésie & Réanimation     Full-text available via subscription   (Followers: 2)
Anesthesiology Clinics     Full-text available via subscription   (Followers: 25, SJR: 0.683, CiteScore: 2)
Angiología     Full-text available via subscription   (SJR: 0.121, CiteScore: 0)
Angiologia e Cirurgia Vascular     Open Access   (Followers: 1, SJR: 0.111, CiteScore: 0)
Animal Behaviour     Hybrid Journal   (Followers: 227, SJR: 1.58, CiteScore: 3)
Animal Feed Science and Technology     Hybrid Journal   (Followers: 7, SJR: 0.937, CiteScore: 2)
Animal Reproduction Science     Hybrid Journal   (Followers: 7, SJR: 0.704, CiteScore: 2)

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Similar Journals
Journal Cover
Advanced Powder Technology
Journal Prestige (SJR): 0.694
Citation Impact (citeScore): 3
Number of Followers: 17  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 0921-8831 - ISSN (Online) 1568-5527
Published by Elsevier Homepage  [3181 journals]
  • Material development using the inherent features of nano-cellulose and
           nano-chitin: Necessity of simple processes and cross-disciplinary
           collaboration
    • Abstract: Publication date: Available online 17 November 2019Source: Advanced Powder TechnologyAuthor(s): Yoshikuni Teramoto For nano-cellulose materials, which have attracted attention in both academia and industry in recent years, to be used as a truly valuable material class, the author believes that their processing procedures must be both rational and simple. In addition, it is important to focus on areas where the outcomes cannot be achieved without these particular nanomaterials. These points also apply to nanomaterials obtained from the animal structural polysaccharide chitin. On this basis, the author’s group has recently achieved “creation of micro-patterning cell culture substrate by inkjet printing of chitinous nanocrystals” and “utilization of cellulose nanofibers as a module for microfluidic paper-based analytical device (μPAD)”. The direction of these projects also reflects some of the activities of the applied life science department that the author worked for until recently. Cellulosic materials, including traditional forms for industrial use, often exist as a powder state at some point in the production process. The author hopes that research on nano-cellulose and nano-chitin will be enhanced through collaboration with powder technology researchers.Graphical abstractGraphical abstract for this article
       
  • A correlation story of syntheses of ZnO and their influence on
           photocatalysis
    • Abstract: Publication date: Available online 17 November 2019Source: Advanced Powder TechnologyAuthor(s): Soumitra Payra, Sankalp Koduvayur Ganeshan, Swapna Challagulla, Sounak Roy The crystallinity, surface morphology, porosity and band structure of semiconducting catalytic materials greatly influence their photocatalytic efficiency. Here, the semiconducting ZnOs were synthesized with three different synthetic routes of precipitation, solution combustion and direct calcination of precursor. All the synthesized catalysts were characterized thoroughly by X-ray diffraction, Field emission scanning electron microscopy, diffuse reflectance spectroscopy, Brunauer–Emmett–Teller surface area and photoluminescence. The synthesized catalysts show different nano-crystallinity, morphology, surface properties and band structure depending on the synthetic methods. All the synthesized catalysts were explored for photocatalytic degradation of methylene blue under visible and UV light illumination. The correlation between the physical properties and catalytic efficacy were established. The complete mechanism for the photocatalytic degradation of methylene blue was also proposed. The typical band structure and the longer life of excitons due to the presence of defects in solution combustion synthesized ZnO overpowered the other physical properties in influencing the visible and UV light assisted methylene blue degradation. This work shades light on the key controlling factors of a photocatalytic reactions and provides simple strategy for the development of efficient photocatalysts for solar energy conversion applications in solving energy crisis and environmental pollution problems.Graphical abstractGraphical abstract for this article
       
  • Three-dimensional periodic structures of gold nanoclusters in the
           interstices of sub-100 nm polymer particles toward surface-enhanced
           Raman scattering
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Ayumi Yahata, Haruyuki Ishii, Kosuke Nakamura, Kanako Watanabe, Daisuke Nagao Regularly ordered polymer nanoparticle (PNP) assemblies incorporating gold nanoparticle (Au NP) clusters into the PNP interstices were fabricated by a simultaneous deposition of PNPs and Au NPs on a glass substrate. Monodisperse PNPs with an average size of 66 nm were employed as a template in the co-assembly to create the sub-100 nm periodic Au nanostructures on the substrate. First, mono-layering of PNP array with incorporation of 14 nm Au NPs was performed by a drop-casting to examine the number ratio of Au NPs to PNPs for multi-layering. Absorption spectra of the mono-layered co-assemblies of PNPs and Au NPs were employed to characterize the clustered state of Au NPs in the interstices of mono-layered PNPs. The number ratio suitable for homogeneous incorporation of Au NPs clustered in the interstice was found to be ranged from 6 to 8 in the characterization. Then, multi-layered co-assemblies of PNPs and clustered Au NPs were fabricated by a vertical deposition method with the Au NP number ratio of 8 to PNPs. Lifting rate of the substrate on which the PNPs were deposited was varied in the vertical deposition method to tune the film thickness of NP co-assembly. A decrease in the lifting rate to 1 μm/s could thicken the film to 0.71 μm corresponding to 13 layers of PNPs, resulting in the fabrication of periodic structures of Au NP clusters with a high packing density. Signal-to-noise ratio in the Raman measurement using p-mercaptobenzoic acid as a target molecule was successfully enhanced by multi-layering of the co-assembly, indicating that Au NP clusters were homogeneously incorporated into the interstices of PNPs in the co-assemblies.Graphical abstractGraphical abstract for this article
       
  • Collision dynamics of wet particles: Comparison of literature models to
           new experiments
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Britta Buck, Stefan Heinrich Collision dynamics of wet particles are often investigated in literature, since their knowledge is important for the design and modeling of granular process involving liquid layers or moisture. Several models were already reported predicting rebound behavior of wet particles. However, most of them are either developed for a viscous dominant regime, neglecting capillary effects all together, or capillary effects are strongly simplified. This work summarizes the various models and compares them to new experimental results for liquids at small and moderate viscosities, to check for applicability also for these materials. Several discrepancies between experiments at small liquid viscosities and models were found and reasons for these differences are discussed. Mainly, the negligence or simplification of capillary forces regarding energy dissipation during the collision leads to an overprediction of rebound velocities compared to the experiments reported in this work. Furthermore, selection of appropriate models for viscous forces during wet particle collisions has to be conducted with care.Graphical abstractGraphical abstract for this article
       
  • Amine-impregnated MCM-41 in post-combustion CO2 capture: Synthesis,
           characterization, isotherm modelling
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Satyajit Mukherjee, Akshay, Amar N. Samanta In this study, a composite mesoporous silica material MCM-41 (Mobil composite matter) is impregnated with monoethanolamine (MEA) as primary linear amine, benzylamine (BZA) as primary cyclic amine and N-(2-aminoethyl) ethanolamine (AEEA) as secondary diamine and the effects of amine loading, amine type, CO2 partial pressure and adsorption temperatures on the CO2 adsorption are investigated. The CO2 adsorption performances of MCM-41 and amine impregnated MCM-41 samples are studied up to 1 bar of CO2 partial pressure and the temperature range of 25–60 °C. The amine loadings (% impregnation) are optimized for maximum CO2 uptake. The materials are characterised using N2 adsorption/desorption isotherm, Fourier Transform Infrared (FT-IR) Spectroscopy, Thermogravimetric (TGA) and Elemental (CHNS) analysis. The materials have shown good structural and thermal stability. The MCM-41-40%AEEA, MCM-41-40%BZA and MCM-41-50%MEA samples are exhibited the CO2 adsorption capacity of 2.34 mmol/g (102.98 mg/g), 0.908 mmol/g (39.96 mg/g) and 1.47 mmol/g (64.69 mg/g) respectively. The CO2 uptake of MCM-41-40%AEEA is 3.5 times higher than that of in MCM-41 (0.68 mmol/g) and it is also the highest reported value as di-amine impregnated MCM-41. The results indicated that the adsorption capacities of the materials (MCM-41 and MCM-41-40%AEEA) are decreased with an increase of adsorption temperature in the range of 25–60 °C. The Freundlich, Langmuir, Sips and Toth isotherm models are used to correlate and predict experimental CO2 adsorption data. The Sips and Toth isotherm models are found to be better fitted with the experimental data. The isosteric heat of adsorption of MCM-41 and MCM-41-40%AEEA samples are also calculated from Van’t Hoff plot using iSorbHP-win instrumental analysis software in the experimental temperature range.Graphical abstractGraphical abstract for this article
       
  • Influence of clean air and inlet configuration on the performance of slit
           nozzle virtual impactor
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Muhammad Zeeshan Zahir, Ji-Eun Heo, Se-Jin Yook A two-partitioned horizontal inlet was developed for improving the collection efficiency and minimizing the wall loss problem in slit virtual impactor. The two-partitions were provided to simultaneously supply both aerosol and clean air to the virtual impactor. Both numerical and experimental investigations were carried out on the developed inlet configuration by considering different flowrate ratios of aerosol to clean air. The horizontal inlet was helpful in reducing the cutoff diameter, whereas the clean air prevented the particle deposition on the virtual impactor walls. The performance of two-partitioned horizontal inlet was compared with the conventional vertical inlet configuration for PM2.5, PM5 and PM10 virtual impactors. All the operating conditions and geometric parameters, such as the inlet flowrate; the width of collection nozzle; the width, length and span of acceleration nozzle; and the distance between collection and acceleration nozzles, were kept the same and only the inlet configuration was changed. The major-to-total flowrate ratio was kept at 0.9 and minor-to-total flowrate ratio at 0.1. It was observed that by using the two-partitioned horizontal inlet configuration, the cutoff diameters for PM2.5, PM5 and PM10 virtual impactors, were reduced by 16%, 10% and 11%, respectively, while the wall loss of particles near the cutoff size in all three cases were reduced from 16% to about 1%.Graphical abstractGraphical abstract for this article
       
  • Synthesis and characterization of new nanosphere hybrid nanocomposite
           polyoxometalate@ceramic@polyaniline as a heterogeneous catalyst for
           oxidative desulfurization of real fuel
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Mohammad Ali Rezvani, Parvin Rahmani In this manuscript, the catalytic oxidative desulfurization (CODS) was proceeded using PMoV@CuO@PAN hybrid nanocatalyst. The nanocatalyst was prepared by the composition of potassium salt of 11-molybdo-1-vanadophosphat (PMoV), copper oxide (CuO), and polyaniline (PAN). The samples were characterized through various methods like FT-IR, XRD, SEM, and EDX. Thiophene (Th), benzothiophene (BT), and dibenzothiophene (DBT) were selected as the target sulfur compounds for CODS of simulated fuel. The oxidation processes were conducted under different conditions to evaluate the effects of individual reaction variables, including reaction time, reaction temperature, and nanocatalyst dosage. Moreover, a kinetic study was carried out and the activation energies for CODS of Th, BT, and DBT were determined. The investigations on CODS of real gasoline revealed that the sulfur content was reduced from 0.4987 to 0.0246 wt% and the mercaptans concentration was lowered from 98 to 5 ppm. Based on experimental results, the PMoV@CuO@PAN nanocatalyst retained a high removal yield of DBT compound after five rounds of reaction cycles and can be used as a reusable hybrid heterogeneous nanocatalyst in CODS treatments.Graphical abstractGraphical abstract for this article
       
  • Effect of nonlinear thermal radiation on 3D magneto slip flow of
           Eyring-Powell nanofluid flow over a slendering sheet with binary chemical
           reaction and Arrhenius activation energy
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): S.R.R. Reddy, P. Bala Anki Reddy, Krishnendu Bhattacharyya An analysis is performed to study the combined effects of nonlinear thermal radiation, Arrhenius activation energy, chemical reaction and heat generation/absorption on the steady three-dimensional magnetohydrodynamic flow of Eyring-Powell nanofluid flow over a slendering stretchable sheet with velocity, thermal and solutal slips. The prevailing partial differential equations are transmuted into coupled non-linear ordinary differential equations via with the suitable similarity transformations. The resultant non-linear coupled differential equations are solved numerically by using the R-K 4th order method along with shooting scheme. The results are calculated to measure the influence of sundry parameters on velocity, temperature, concentration, shear stress, temperature gradient and concentration gradient are presented graphically and in tabular form. It is noticed that the temperature is more impactable for higher values of radiative heat transport. The local Sherwood number decays exponentially for all the values of the chemical reaction parameter. We compared the present results for the limiting cases with previously published results, which has shown reliability and efficiency.Graphical abstractPhysical configuration of the problem.Graphical abstract for this article
       
  • Ag/AgCl-GO: A composite for degradation of Rhodamine B in dye wastewater
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Cuiling Ai, Sikai Yang, Fan Zhang, Xiangwen Shao, Junge Xu Ag/AgCl-GO composite was fabricated by deposition–precipitation method and photoplasmic reduction method at room temperature. The resulting products were characterized by XRD, XPS, SEM, TEM, Zeta potential and UV–Vis DRS. The results indicated that the samples were composed of Ag, AgCl and graphene oxide (GO). During the photoreduction, the crystallinity of Ag0 particles gradually increased with prolonging the time of UV irradiation, then remained stable after 90 min. The addition of GO had little effect on the crystal structure of Ag/AgCl, however, this reduced the particle size and enhances the dispersibility of the composite. After 100 min of visible light irradiation, the degradation efficiency of rhodamine B (RhB) reached 98.43%. Therefore, the Ag/AgCl-GO photocatalyst exhibited significant photocatalytic activity during the degradation of RhB under visible light.Graphical abstractSynthesis mechanism of Ag/AgCl-GO composites. A negatively charged group (OH, COOH, etc.) on GO adsorbs Ag+ in the solution under the action of electrostatic force. AgCl particles were supported on the thin layer of GO by adding the KCl dropwise. The generated electrons by the intrinsic excitation of AgCl migrated to its surface and were captured by Ag+ to form Ag0 under ultraviolet light.Graphical abstract for this article
       
  • Recyclable and highly efficient photocatalytic fabric of
           Fe(III)@BiVO4/cotton via thiol-ene click reaction with visible-light
           response in water
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Haisheng Zhang, Dan Yu, Wei Wang, Pin Gao, Lishan Zhang, Shan Zhong, Baojiang Liu In this article, we designed a photocatalytic cotton fabric of Fe(III)@BiVO4/cotton via thiol-ene click reaction and achieved an enhanced photocatalytic performance and excellent recyclability under visible-light irradiation. The Fe(III)@BiVO4 and cotton fabric were modified with KH570 (including CC groups) and KH580 (including SH groups), respectively. Then, the Fe(III)@BiVO4/KH570 and KH580/cotton reacted and connected via thiol-ene click reaction, which can effectively solve its recyclability in practical application and realize ideal all-in-one structure. The as-prepared Fe(III)@BiVO4/cotton not only exhibited an excellent photocatalytic performance in reducing Cr(VI) to Cr(III), but also showed a remarkable performance in degradation of C.I. reactive blue 19 (RB-19) under visible-light. Meanwhile, various analysis technique were used to confirm the successful connection between Fe(III)@BiVO4 and cotton fabric via thiol-ene click reaction. Moreover, the photocatalytic mechanism was also discussed comprehensively in view of trapping experiments and ESR analysis.Graphical abstractThe process of synthesizing the Fe(III)@BiVO4/cotton fabric and the possible mechanism of reduction of Cr(VI) and oxidation of RB-19 under visible-light irradiation.Graphical abstract for this article
       
  • Superparamagnetic magnesium ferrite/silica core-shell nanospheres: A
           controllable SiO2 coating process for potential magnetic hyperthermia
           application
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Harinarayan Das, Nipa Debnath, Takashi Arai, Takahiko Kawaguchi, Naonori Sakamoto, Kazuo Shinozaki, Hisao Suzuki, Naoki Wakiya The control of coating shell becoming important to improve the applicability of magnetic nanoparticles. Herein, we present the scalable technique for preparing MgFe2O4/SiO2 core-shell nanospheres with finely tuned shell thickness and their efficiency in magnetic hyperthermia heating agent. At first, MgFe2O4 dense nanosphere derived from one-step ultrasonic spray pyrolysis (USP) technique. Silica shells were then coated on the as prepared nanospheres with tunable thickness from 10 to 30 nm. We show that the thickness of this coating is finely controlled at allowing our proposed level by using the required amount of SiO2 precursor (SiC8H20O4)/acidic catalyst (HCl) ratio where the surface area of core nanospheres are significantly considered. X-ray diffraction reveals the cubic spinel ferrite structure of core particles with crystallite size 9.6 ± 1.8 nm and Fourier transform infrared spectrum analysis confirmed the formation of SiO2. The morphological observation clarified the uniform and smooth SiO2 shell where core-shell nanostructure is highly monodispersed in a liquid medium. M-H loops confirmed the superparamagnetic nature of all samples at room temperature. Significantly reduced ion release concentration in an aqueous solvent of the coated nanospheres compared with uncoated sample demonstrates the hermetically coating feature of dense SiO2. This MgFe2O4/SiO2 core-shell nanospheres with thine SiO2 shell (10 nm) shows effective heating rate in the operative region (
       
  • Particle conveying under microgravity in a vibrating vessel
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): C.X. Li, K.J. Dong, Y.S. Shen, A.B. Yu This paper presents a numerical study on the conveying of particles in a vibrating vessel under microgravity. Such a vessel is composed of parallel plates with sawtooth wavy surfaces, which are specifically designed to convey particles using simple vibration. The numerical model was validated by good agreement between the simulated and experimental results. Then the effects of key variables, including the vessel geometry, vibration amplitude and frequency and gravity level, were systematically investigated by a series of controlled simulations. The results confirm the optimised design from the previous experiments, and numerically demonstrate that using such a system a steady conveying operation can be achieved under microgravity. The convey rate is positively affected by the vibration amplitude and frequency in a complicated way, which cannot be simply described by the commonly used vibration intensity or velocity amplitude. The gravity level also has a significant effect on the convey rate when it is over 0.001g. The convey rate can be estimated by the product of the average solid fraction and velocity. And the effects of the variables can be better understood through the analyses on these two parameters. Finally, a predictive model is proposed to estimate the convey rate under different operational conditions. The findings are useful for the design of particle conveying techniques for outer space applications.Graphical abstractGraphical abstract for this article
       
  • Large eddy simulation of pulverized coal combustion in multi-burner
           system–effect of in-furnace blending method on NO emission
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Masaya Muto, Hiroaki Watanabe, Ryoichi Kurose Large-eddy simulation (LES) is applied to a multi-burner pulverized coal combustion furnace in which three advanced low-NOx burners, each with a coal combustion capacity of approximately 100 kg/h, are vertically installed. The effects of an in-furnace blending method, in which different types of coal (high-fuel-ratio coal and low-fuel-ratio coal) are injected at each burner stage, on NO emission and unburned carbon fraction in fly ash are investigated. Pulverized Newlands coal and Tanito Harum coal that are classified as high-fuel-ratio coal and low-fuel-ratio coal, respectively, are used as fuels. The results indicate that oxygen is consumed rapidly and NO decreases near the burner from which the high-fuel-ratio coal is injected because the reducing atmosphere becomes dominant owing to the lack of oxygen. Further, the unburned carbon fraction decreases when low-fuel-ratio coal is injected from the upper burner because the residence time is longer for the combustion of high-fuel-ratio coal than when low-fuel-ratio coal is injected from the lower burner.Graphical abstractComparisons of contour distributions of gas temperature and NO mole fractions between simulations and experiments.Graphical abstract for this article
       
  • Characteristics of a single jet injected into an incipiently fluidized
           bed: A magnetic resonance imaging study
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): C.M. Boyce, A. Penn, M. Lehnert, K.P. Pruessmann, C.R. Müller Rapid magnetic resonance imaging (MRI) was used to characterize properties of a single central gas jet injected into a 3D gas fluidized bed under incipient fluidization conditions. Snapshots of both particle concentration and particle velocity are provided. The average jet height, oscillations in jet height and the size of bubbles breaking off from the jet increased with increasing jet velocity. The frequency of bubble breakoff from the jet decreased with increasing jet velocity. The jet height measurements are compared with various correlations in the literature, and the quantitative data provided here can be compared directly with that from numerical simulations and theoretical predictions for validation purposes.Graphical abstractGraphical abstract for this article
       
  • Simulation of coal pressurized pyrolysis process in an industrial-scale
           spout-fluid bed reactor
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Guanwen Zhou, Wenqi Zhong, Aibing Yu, Jun Xie A three-dimensional Eulerian-Lagrangian model, facilitated with multiphase particle-in-cell (MP-PIC) method, was developed to simulate gas-solid flow and pyrolysis characteristics of coal (with the capacity of 500 thousand tons per year) in an industrial-scale spout-fluid bed reactor (H = 16.6 m and D = 3.1 m), aiming at providing guidance for industrial application of pressurized grade conversion of coal. The performance of the reactor and the effects of operating parameters such as coal feeding rate, semi-coke to coal ratio, and particle sizes were numerically investigated. It was found that the flow pattern in this case is a “jet in the fluidized bed with bubbling”. The raise of pressure has a positive impact on the spouting structure and the flow uniformly. The increase of the semi-coke to coal ratio is beneficial to the coal pyrolysis, but the improvement of the pyrolysis is limited and the number of particles in the reactor will be sharply increased. With the increase of particle sizes, the flow pattern in the pyrolysis reactor tends to be stable while the mixing effectiveness is getting worse. It is suggested that the particle size of the material should range within 0–6 mm.Graphical abstractGraphical abstract for this article
       
  • Preparation, formulation and deposition of mica flake supported cobalt
           oxide for nanostructured lithium ion battery anodes
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Alexandra Helmer, Anna Sophie Rink, Julian Esper, Yanlin Wu, Julien Bachmann, Robin N. Klupp Taylor We describe the fabrication and morphological and electrochemical characterisation of lithium ion battery anodes whereby the active material is supported on flake-like microparticles. Using various physical analytical techniques we verify that nanostructured cobalt (II, III) oxide can be directly grown onto commercial titanium dioxide-coated mica flakes by a liquid phase oxidation route. We then investigate the formulation and deposition of this material along with carbon black in order to form electrodes. Here we consider two binder/solvent systems, one widely used based on polyvinylidene fluoride in N-methy-2-pyrrolidone, and one more recently identified based on sodium alginate in water. We show that the latter system is preferable for the formation of anodes using the cobalt oxide coated flake-like particles as it leads to a more homogeneous distribution of active and conductive material in the electrode. Using cyclic voltammetry and electrochemical impedance spectroscopy we show that this feature improves the access to active material and facilitates efficient charge transfer in the electrode while maintaining electrode integrity. Moreover, an electrode based on the alginate binder exhibited a high reversible specific capacity of 650 mAh/g along with 84.8% capacity retention after 70 cycles. Overall our study indicates the promise of including shape anisotropic particles such as microflakes in battery electrodes.Graphical abstractGraphical abstract for this article
       
  • A facile preparation of graphene/reduced graphene oxide/Ni(OH)2 two
           dimension nanocomposites for high performance supercapacitors
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Jie Tian, Qian Shan, Xianglu Yin, Wei Wu A Ni(OH)2 composite with good electrochemical performances was prepared by a facile method. Ni(OH)2 was homogeneously grown on the hydrophilic graphene/graphene oxide (G/GO) nanosheets, which can be prepared in large scale in my lab. Then G/GO/Ni(OH)2 was reduced by L-Ascorbic acid to obtain G/RGO/Ni(OH)2. Caused by the synergy effects among the components, the G/RGO/Ni(OH)2 electrode showed good electrochemical properties. The G/RGO/Ni(OH)2 electrode possessed a specific capacitance as high as 1510 F g−1 at 2 A g−1 and even 890 F g−1 at 40 A g−1. An asymmetric supercapacitor device consisting of G/RGO/Ni(OH)2 and reduced graphene oxide (RGO) was installed and displayed a high energy density of 44.9 W h kg−1 at the power energy density of 400.1 W kg−1. It was verified that the G/GO nanosheets are ideal supporting material in supercapacitor.Graphical abstractGraphical abstract for this article
       
  • What dominates heat transfer performance of hybrid nanofluid in single
           pass shell and tube heat exchanger'
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): S. Anitha, Tiju Thomas, V. Parthiban, M. Pichumani Influence of nanoparticle volume concentration and proportion on heat transfer performance (HTP) of Al2O3 – Cu/water hybrid nanofluid in a single pass shell and tube heat exchanger is analyzed. Multiphase mixture model is adopted to model the flow. Three-dimensional governing equations and associated boundary conditions are solved using finite volume method. The numerical results are validated with the experimental results. Results indicate that optimized nanoparticle volume concentration and proportion dominate HTP of hybrid nanofluid. Heat transfer coefficient and Nusselt number are monotonic increase functions of nanoparticle volume concentration and proportion. The percentage increase in heat transfer coefficient of hybrid nanofluid is 139% than water and 25% than Cu/water nanofluid. At higher Reynolds number, the increment in Number of Transfer Units (NTU) between water and hybrid nanofluid is close to 75%. Maximum enhancement in Nusselt number for hybrid nanofluid exceeds 90% when compared to nanofluid (Al2O3/Water nanofluid). Consequently, highest heat transfer performance is attained for hybrid nanofluid systems. Effectiveness of heat exchanger increases almost to 124% when hybrid nanofluid is employed. We show that it is higher than water as well (conventional coolant). Results are expected to be helpful in further industrial-scale deployment of nanofluids, which is an area that is currently relevant for ongoing academia-industry partnership efforts worldwide.Graphical abstractGraphical abstract for this article
       
  • Synthesis of (Sn,Zn)(O,S) bimetallic oxysulfide catalyst for the
           detoxification of Cr+6 in aqueous solution
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Osman Ahmed Zelekew, Dong-Hau Kuo, Hairus Abdullah Herein, we report the bimetallic (Sn,Zn)(O,S) oxysulfide nanocatalyst with a facile method. The Sn-based catalyst with the addition of Zn was synthesized with the proportions of 0, 20, 30 and 50% of Zn to Sn precursors for preparation. The catalysts were characterized by XRD, TEM, SEM XPS, and UV–vis instruments. The nanocatalysts were also tested for the detoxification of Cr+6. The Sn-20 catalyst with 20 M percent of Zn(Ac)2·2H2O showed an excellent performance for the induced photocatalytic reduction of Cr+6 under visible light irradiation at room temperature. The complete reduction of Cr+6 was achieved within 80 min by Sn-20 catalyst. However, 85.6, 97, and 94% of Cr+6 reductions were achieved within 80 min under visible light illumination by Sn-0, Sn-30, and Sn-50 catalysts, respectively. Hence, the bimetallic (Sn,Zn)(O,S) oxysulfide nanocatalyst will be a candidate and highly potential material for the detoxification of Cr(VI)-containing polluted water.Graphical abstractThe reduction reaction mechanism for Cr(VI) under visible light by Sn-20 catalyst.Graphical abstract for this article
       
  • Synthesis of monodispersed silver particles: Synthetic techniques to
           control shapes, particle size distribution and lightness of silver
           particles
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Kanetaro Sannohe, Tingli Ma, Shuzi Hayase The purpose of this paper is to give process for preparing monodispersed silver particles with round shape having aspect ratio of 1, because the shape is suitable for preparing silver grids with fine pattern size. We found that the combination of gelatin and hydrazine gave the monodispersed silver particles with the aspect ratio of 1. Presence of the high molecular compounds is crucial probably because they are adsorbed on the surface of growing silver particles and control the uniform crystal growth. In addition, the relationship between these reaction conditions and the particle shape are discussed in detail.Graphical abstractGraphical abstract for this article
       
  • Active electrode materials of graphene balls and their composites for
           supercapacitors: A perspective view
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Chongmin Lee, Sun Kyung Kim, Hankwon Chang, Hee Dong Jang In recent years, supercapacitors have received considerable research attention for energy storage systems due to their high-power density, fast charge-discharge processes, and long cycle life. The superior performance of supercapacitors is considerably dependent on the electrode materials. Among electrode materials, graphene balls (GBs) and their composites have recently attracted strong interest. They are considered ideal for the fabrication of electrode materials because of their unique characteristics of large specific surface area and superior electric conductivity, which should make them very effective for use in supercapacitors. In particular, GBs and their microstructured composites have recently been proven promising candidates for supercapacitor electrodes. Their unique 3D morphology provides highly porous graphene structures for decoration with active materials. In this perspective, recent studies were highlighted and discussed that focus on GBs and their composites for the potential energy storage devices called supercapacitors, (i.e., electric double layer capacitors and pseudocapacitors).Graphical abstractGraphical abstract for this article
       
  • The effect of copper granules on interfacial bonding and properties of the
           copper-graphite composite prepared by flake powder metallurgy
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Manish Dixit, Rajeev Srivastava The study evaluates the effect of introducing Cu granules and control milling on the microstructure, interfacial bonding and mechanical properties including sintered density, hardness, compressive strength, flexural strength and electrical conductivity of Copper-Graphite (Gr) composite synthesize by flake powder metallurgy (Flake PM). It develops the flake composite particles by control mechanical alloying (MA) which further laminates over the refine granules surface. This encapsulation facilitates the strong interfacial bonding among the composite constituents during sintering. Results highlight that the 10% Cu granules in Cu-10Gr composite exhibit excellent mechanical properties. It increases the relative density, hardness, compressive strength, and flexural strength by 4.19%, 28.23%, 98.31%, and 11.8% respectively. However, the electrical conductivity increases by 6.73% (%IACS) for 15% of Cu granules in the Cu-10Gr composite. The improvements in the results are the synergistic coordination of dispersion homogeneity, surface integrity, work hardening, and the superior interfacial adhesion between composite powder and Cu granules.Graphical abstractGraphical abstract for this article
       
  • Numerical simulation of gas-solid flows in fluidized bed gasification
           reactor
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Akhilesh Kumar Sahu, Vasudevan Raghavan, B.V.S.S.S. Prasad A numerical model for simulating a fluidized bed gasifier should include appropriate parameters to capture the dynamics of gas-solid flows, gasification kinetics and the interaction between these two. The focus of the present study is to analyze the effects of coal gasification chemistry models reported in literature on the prediction of product gas composition in a fluidized bed gasification reactor. Numerical results are validated against the experimental data available in literature. The validated model is used to examine the available chemical kinetics schemes for water gas shift reaction, steam methane reforming reaction and char heterogeneous reactions. It is also used to assess the effects of hydrodynamic models parameters such as drag model, particle-particle restitution coefficient and specularity coefficient on exit gas composition. Results show that the predictions of product gas composition are notably affected by the choices of the kinetics schemes for water gas shift and steam methane reforming reactions. Systematic analysis using the available choices to simulate initial processes such as moisture removal, volatile and tar cracking is reported. Drag models and the value of specularity coefficient are shown to have no effect on product gas composition, and the particle-particle restitution coefficient slightly influences the predicted gas composition.Graphical abstractGraphical abstract for this article
       
  • Development of the fumed TiO2 having high content of rutile structure and
           dispesibility using the dry-type of surface modification and the thermal
           treatment
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Yukiya Yamashita, Masayoshi Fuji The effect of dry-type surface modification of a fumed TiO2 and the thermal treatment were studied to synthesize the new fumed TiO2 having a high content of rutile structure and high dispersibility. The fumed TiO2 was modified with various metallic alkoxides to prepare precursors and next the resulted precursors were thermally-treated by the novel natural dropping method with a very short heating time, less than 1 s. The focus of this investigation was on the metallic alkoxide species as a surface modification agent and morphologies of both the precursor and thermally-treated fumed TiO2. The morphologies and nanostructures of the obtained fumed TiO2 were characterized. The carbon content and agglomerate of the precursor influenced on the transformation ratio from anatase to rutile structure. It was confirmed that the dry-type surface modification with tetraethoxysilane (TEOS) and titanium tetra-isopropoxide (TTIP) at room temperature is very effective method to prepare precursors for the next thermal treatment. The thermally-treated fumed TiO2 modified with TTIP showed 100% rutile structure with pure TiO2 composition at 1400 °C. The thermally-treated fumed TiO2 modified with small quantities of TEOS exhibited both 100% rutile structure and excellent dispersibility. This high dispersibility caused from a sponge-like structural characteristic of the agglomerate and static electricity repellence by coated SiO2 layer. The thermally-treated fumed TiO2 modified with TEOS and TTIP showed the color tone shift can be attributed to rutile structure. It was revealed that the combination of dry-type surface modification and natural dropping thermal treatment is an attractive method to prepare the new fumed TiO2 with 100% rutile structure maintaining the high dispersiblity.Graphical abstractGraphical abstract for this article
       
  • Simulation on coal-fired supercritical CO2 circulating fluidized bed
           boiler: Coupled combustion with heat transfer
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Ying Cui, Wenqi Zhong, Jun Xiang, Guoyao Liu Using supercritical carbon dioxide (S-CO2) as the working fluid integrated in a circulating fluidized bed (CFB) boiler is a rising technology used to improve the power generation efficiency and reduce gas pollutant emissions in coal-fired power generation systems. This study established a comprehensive 3-D model based on an Eulerian-Lagrangian frame to simulate the combustion process. A new method was presented using constant heat flux as the boundary obtained from the coupled simulation of heat transfer and combustion. The gas phase was described with large eddy simulation (LES). The solid phase used the multi-phase particle-in-cell (MP-PIC) approach. Simulations were carried out in a 10 MW S-CO2 CFB boiler (with cross section area of 3.557 × 3 m2 and height of 21.01 m). Combustion characteristics obtained in boundary heat flux and excess air ratio were numerically investigated. Results showed that the temperature profile was relatively uniform in the whole boiler and the furnace temperature increased with the increase of boundary heat flux. Emissions of CO2 and SO2 declined with the increase of boundary heat flux while CO emission increased. An increased excess air ratio caused a decrease in furnace temperature and the rise of CO and SO2. The characteristics of combustion and pollutant emissions were optimal with the heat flux at around 25–37 kW/m2 and an excess air ratio at 1.18–1.25.Graphical abstractGraphical abstract for this article
       
  • Refining single-crystalline epsilon iron oxide nanorods via
           low-temperature aging
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Ji Ma, Yunguo Wang, Kezheng Chen Refinement of ε-Fe2O3 phase in ε-Fe2O3/SiO2 composite powder is an urgent need in terms of its practical applications in high-density magnetic storage media. In this work, two types of refinement routes were employed for this purpose. It was found that short-time tempering treatment was not an ideal route for the refinement, because ε-Fe2O3 nanorods were ruptured to nanoparticles with an extremely wide size distribution, and their low coercivity of merely 1.0 kOe was not desirable for expected applications. By contrast, low-temperature aging route facilitated the formation of uniform ε-Fe2O3 nanorods with a length of about 200 nm and a width of about 40 nm. Because of their narrow size distribution and high crystallinity, these nanorods possessed large coercivity around 19 kOe, pronounced remanent squareness and prominent thermomagnetic behaviors, making them fairly desirable for further applications in magnetically-relevant field.Graphical abstractGraphical abstract for this article
       
  • Clusters identification and meso-scale structures in a circulating
           fluidized bed based on image processing
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Shangyi Yin, Wenqi Zhong, Tao Song, Ping Lu, Yuhang Chen To understand the behaviors of particle clusters in the circulating fluidized bed (CFB), experiments were conducted with glass beads to acquire the image sequences of gas-solid flow on a CFB riser with a 100 mm × 25 mm cross-section and 3.2 m in length by adopting high-speed photography. An image multilevel thresholding approach using k-means algorithm was applied to perform image segmentation to identify clusters as well as core clusters in the riser, automatically. Cluster characteristics, such as the density and the number of clusters were obtained subsequently. The results show the image segmentation method based on k-means algorithm has made some improvement in terms of precision and systematicness for cluster identification. In addition, the internal structure of the cluster was analysed. Collectively, the cluster always consists of a dense core with highest solids holdup surrounded by a relatively dilute cloud with no clear boundary. High solids holdup enhances the cluster formation. On the contrary, the core cluster disappears at low solids holdup condition, indicating the cluster is only composed of cluster cloud in this case. Furthermore, based on the present experimental data, the correlations between the cluster density and the local time-mean solids holdup are presented.Graphical abstractParticle clustering behaviors in circulating fluidized bed riser are experimentally investigated by the high-speed video system. An image multilevel thresholding approach using k-means algorithm is developed to perform image segmentation to identify the cluster as well as its internal structure. Additionally, the dynamics properties of particle clusters are discussed.Graphical abstract for this article
       
  • Coupled DEM-SPH simulations of wet continuous screening
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Darius Markauskas, Harald Kruggel-Emden During screening, a liquid stream, besides the vibration, can be applied for the acceleration of the separation. The discrete element method coupled with the smoothed particle hydrodynamics (DEM-SPH) is used to numerically analyse wet continuous screening here. Within the applied DEM-SPH a new simple model for the representation of the screening surface is suggested in this study. In this model, the influence of the screening surface on the fluid is represented using external forces, which act on the SPH particles in close vicinity of the screen. A required validation of the DEM-SPH method for the analysis of a vibrated particle-laden system is performed by comparing obtained DEM-SPH results with the results derived using the DEM coupled with finite volume method. The performed simulations of dry and wet continuous screening demonstrate that flowing water, in most simulated cases, accelerates the separation of particles. The presented study demonstrates the potential of the coupled DEM-SPH method for the analysis of wet screening processes. To our best knowledge, the simulation of wet screening using a two-way coupled numerical DEM-SPH approach not resolving the flow around individual particles is demonstrated in the scientific literature for the first time.Graphical abstractGraphical abstract for this article
       
  • Diffusion mechanism and release profile of a multivitamin from
           TiO2 hollow particles
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Yoko Tominaga, Kazunori Kadota, Akira Kitayama, Atsuko Shimosaka, Mikio Yoshida, Yoshiyuki Shirakawa The present study aimed to control the release rate profile of a multivitamin that has hydrophilic and hydrophobic properties and to investigate its diffusion rate from titanium dioxide (TiO2) hollow particles. The TiO2 hollow particles encapsulating the vitamins C and E were prepared via a sol-gel process using an inkjet nozzle. The obtained particles were evaluated by scanning electron microscopy and energy dispersive X-ray spectroscopy. The sustained release rate was estimated by the dialysis bag method. Additionally, a diffusion mechanism for the multivitamin from the TiO2 hollow particles was proposed.TiO2 particles prepared by this method exhibited spherical porous structures. The TiO2 hollow particles were successful in encapsulating both the hydrophilic vitamin C and the hydrophobic vitamin E, resulting in a sustained release profile for these two components from the TiO2 hollow particles. The release behavior of the multivitamin was quite different from that of each single vitamin. This is related to the adsorption state of each vitamin on the TiO2 particle surface. The effective diffusion coefficient of VC derivative (8.403 × 10−13 cm2/s) was faster than that of VE derivative (1.671 × 10−13 cm2/s). This tendency may be attributed to the difference between hydrophilic and hydrophobic properties. Additionally, the value of effective diffusion coefficient in multi-component was always larger than that in single component. The value of Knudsen diffusion coefficient in VC and VE derivative was 2.684 × 10−3 and 2.264 × 10−3 cm2/s, respectively. In all samples, Knudsen diffusion coefficient was larger than molecular diffusion coefficient. The diffusion mechanism of the active ingredients likely depends on the pore size of TiO2 and the molecular size of the active ingredients.Graphical abstractGraphical abstract for this article
       
  • Time-dependent evolution pathway of CIGSe nanocrystals by low-temperature
           process
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): M. Latha, R. Aruna-Devi, S. Velumani, Jaime Santoyo-Salazar, F. de Moure-Flores We report a systematic time-dependent investigation of Cu(In0.7, Ga0.3)Se2 nanocrystals (CIGSe NCs) by the hot-injection process at low reaction temperature. The reaction time was varied from 0 min to 16 h, to study the reaction mechanism and growth process of CIGSe NCs. Structural analysis showed the formation of β-CuSe phase at 0 min and mixed phase of β-CuSe and CIGSe, when the reaction time was between 5 min and 4 h. The size of NCs was increased from 3 to 38 nm as the reaction time increases. The composition of Cu/(In + Ga) was decreased while Ga/(In + Ga) increased as a function of reaction time. Based on the results, the possible formation mechanism of CIGSe NCs was proposed. The sequence of CIGSe formation is initiated from binary β-CuSe and then the mixture of β-CuSe and CIGSe, which subsequently transferred to single phase CIGSe by gradual incorporation of In3+ and Ga3+ ions into the β-CuSe crystal lattice. Formation of single phase CIGSe with the optimum bandgap of 1.24 eV and targeted composition was obtained at 8 h. Additionally, thin films were prepared by drop casting of NCs ink. Single phase CIGSe NCs films showed significant improvement in the morphological, electrical and optoelectronic properties than other films, indicating their potential applicability in low-cost thin film solar cells.Graphical abstractGraphical abstract for this article
       
  • Flamelet modeling of laminar pulverized coal combustion with different
           particle sizes
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Xu Wen, Jianren Fan In this work, flamelet modeling of pulverized coal flame stabilized in a laminar counterflow is conducted. Particularly, the effects of particle size on the flamelet model performance are investigated. The a priori tabulated thermo-chemical quantities are compared with the corresponding values in the detailed chemistry solutions, which are obtained by solving the transport equations for all species mass fractions existing in the employed detailed chemical reaction mechanism. The detailed chemistry solutions show that the pulverized coal flame structure can be changed significantly by varying the particle size. While pulverized coal flame structure with small particles is similar to the pure gas flame, it becomes much more complex when the particle Stokes number is larger than unity. Large coal particles can directly cross the flame front to the opposite side and disperse over a large region, resulting a significantly wrinkled flame front and a considerably broadened reaction zone. Comparisons between the tabulated thermo-chemical quantities and the detailed chemistry solutions show that the CH4, O2 and H2O species mass fractions and their RMS (root mean square) values for all cases can be well predicted by the classical flamelet model without any modification, while the peak values of OH mass fraction, gas temperature and heat release rate for the large particle case cannot be correctly captured. For all cases, the mass fractions of combustion-mode-sensitive species cannot be correctly predicted in the premixed flame reaction zone by the employed diffusion-flame-based flamelet model. Such discrepancies are even more pronounced at large particle conditions since the premixed flame reaction zone tends to be broadened.Graphical abstractGraphical abstract for this article
       
  • Relationship between water distribution and shear properties of wet
           granules
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Takumi Kusano, Masaaki Tani, Osamu Hiruta, Hiroshi Nakamura Wet granules are utilized in various fields due to their high workability and cost performance. However, it is difficult to observe the water distribution of wet granules directly because such granules only contain extremely small amounts of water. In this study, the water distribution of wet granules was investigated using a confocal laser microscope and quantitatively analyzed using an autocorrelation function. Furthermore, the correlation length of wet granules estimated from the autocorrelation function was compared with the shear properties of the granules. Consequently, it was found that the internal friction angle of wet granules decreased as the water volume between particles increased. These results indicated that the water in wet granules works as a drag reduction agent under shear conditions.Graphical abstractGraphical abstract for this article
       
  • Synthesis of porous Mg-doped CeO2 powders via self-propagating
           high-temperature synthesis route
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Zahra Hashemzaei, Mahmood Sharifitabar, Hamideh Saravani, Meissam Noroozifar The aim of this study was synthesis of Mg-doped porous cerium oxide powder by self-propagating high-temperature synthesis reaction of Mg-xCeO2-O2 system. Results indicated that doping Mg in the CeO2 crystal structure increased its lattice parameter slightly, and shifted the Ce-O band in the FTIR spectra from 490 to 574 cm−1. Moreover, the EDS results revealed the distribution of Mg in the CeO2 microstructure. There were a high volume fraction of interconnected macro-pores in the microstructure of cerium oxide after the synthesis process. Increase in the x-value from 0.05 to 0.25 mol decreased the mean size and volume fraction of pores from 2.4 to 1 µm and 50 to 30 vol%, respectively. In addition, the BET surface area of porous CeO2 varied between 0.3 and 1.57 m2/g. Finally, it was inferred that the SHS technique can be introduced as a rapid and novel method for synthesis of Mg-doped porous CeO2 powders.Graphical abstractGraphical abstract for this article
       
  • Fluidization using pseudoplastic liquids – Elutriation and ANN
           modeling
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Samit Bikas Maiti, Nirjhar Bar, Sudip Kumar Das Experimental work on elutriation of irregularly shaped sand particles (0.538–2.03 mm diameter) was carried out in three different Perspex columns (47 mm, 72 mm and 92.3 mm) using different non-Newtonian pseudoplastic liquids (0.4–0.8 kg/m3 SCMC solution). The effects of operating parameters, column diameter, bed weight, particle diameter, particle sphericity, liquid rheological properties on the minimum elutriation velocity were examined. The statistically accepted empirical correlation was developed. ANN model could predict the experimental data of minimum elutriation velocity with a correlation coefficient of 0.9951.Graphical abstractGraphical abstract for this article
       
  • Cold-pressing and vacuum arc melting of γ-TiAl based alloys
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): M.N. Mathabathe, A.S. Bolokang, G. Govender, C.W. Siyasiya, R.J. Mostert Beta (β) solidifying γ-TiAl intermetallic alloys of nominal composition Ti-48Al, Ti-48Al-2Nb, Ti-48Al-2Nb-0.7Cr alloys have been cold pressed and vacuum arc melted. The Al loss was due to compaction method used prior to the melting technique, since it was evident after compaction that Al particles migrated to the surface in contact with the die facets after cold pressing. Electron backscatter diffraction (EBSD)-orientation mapping demonstrated that the α-precipitation from the parent β-phase follows the Blackburn orientation relationship (BOR). Microstructural characterization of the alloys was studied by scanning electron microscopy (SEM) equipped with energy dispersion spectroscopy (EDS) for micro-analysis. X-ray diffraction (XRD) technique was used to detect phase compositions.Graphical abstractGraphical abstract for this article
       
  • Template-assisted spray-drying method for the fabrication of porous
           particles with tunable structures
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Asep Bayu Dani Nandiyanto, Takashi Ogi, Wei-Ning Wang, Leon Gradon, Kikuo Okuyama Developing strategies for the production of porous particles with controllable structures using a spray-drying method has attracted attention of researchers for decades. Although many papers have reported their successful production of porous particles using this method, information on how to create and control the porous structures as well as what parameters involving and what formation mechanism occurring during the synthesis process are still not clear. To meet these demands, the present review covers strategies in the spray-drying developments for the fabrication of porous particles with controllable structure. This information is important for optimizing the production of porous particles with desirable properties. Regulation of process conditions and precursor formulations are also explained, including composition, type, and physicochemical properties of droplet and raw components used (i.e., host component, template, and solvent). The electrostatic interactions between the individual components and the droplets are also presented, while this information tends to be neglected in the conventional spray-drying process. To clarify how the porous particles are designed, current experimental results completed with illustrations for the proposal particle formation mechanism are presented. The review also completed with the opportunities and potential roles of the changing porous structures in practical uses. This review would provide information on how to produce porous particles that can be used for advanced functional materials, such as catalysts, adsorbents, and sensors.Graphical abstractGraphical abstract for this article
       
  • A facile preparation of pomegranate-like porous carbon by carbonization
           and activation of phenolic resin prepared via hydrothermal synthesis in
           KOH solution for high performance supercapacitor electrodes
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Jianbing Zang, Pengfei Tian, Guoping Yang, Shaopei Jia, Shuyu Zhou, Hanqing Xu, Yanhui Wang High electrochemical performance pomegranate-like porous carbon was synthesized by the carbonization and activation of phenolic resin which was prepared by adding phenolic resin monomer mixture into KOH aqueous solution and hydrothermal treatment. In the process of hydrothermal, KOH solution could hinder the polymerization of phenolic resin monomer to form big phenolic resin particles. During the carbonization, phenolic resin plays the role of forming small particles and binder during carbonization, which can simultaneously achieve high specific surface area and form three dimensional structures to improve the conductivity. The results showed that pomegranate-like porous carbon composed of small nanometer-scale particles was observed. The obtained porous carbon electrode materials had a high content of micropores with specific surface area as high as 2199.9 m2 g−1. The porous carbon exhibited a high specific capacitance of 341.3 F g−1 at 0.1 A g−1, good rate capability with 71.0% retention from 0.1 to 5 A g−1. Moreover, it showed high capacitance retention of 96.1% after 5000 cycles at a scan rate of 50 mV s−1, indicating excellent cycling stability. The assembled symmetrical supercapacitor showed high energy densities of 17.0 Wh kg−1 and 8.5 Wh kg−1 with the corresponding power densities of 49.6 W kg−1 and 1.8 kW kg−1, respectively. The facile method could be a promising candidate for preparing porous carbon electrode materials with excellent electrochemical performance in the fields of supercapacitors.Graphical abstractGraphical abstract for this article
       
  • Catalytic peroxygen activation by biosynthesized iron nanoparticles for
           enhanced degradation of Congo red dye
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Gautham B. Jegadeesan, S. Amirthavarshini, J. Divya, G.I. Gunarani In this study, biogenic iron (Fe) NPs (B-Fe) were synthesized using Terminalia Bellirica plant extracts and used to activate persulfate (PS) and peroxymonosulfate (PMS) oxidants for degradation of Congo red (CR) dye. Chemogenic Fe-NPs (C-Fe) were also synthesized using borohydride reduction method for comparison. The synthesized Fe NPs were characterized for their surface morphology using Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Dynamic Light Scattering (DLS)-based particle size analysis. Biogenic B-Fe NPs were more uniform in size and smaller (67–125 nm), compared to chemogenic C-Fe (59–277 nm), due to the capping effect of the biomolecules in plant extracts. Degradation efficiencies using the nanoparticle – oxidant system followed the order: C-Fe-PMS (86%) ∼ B-Fe-PMS (83%) > C-Fe-PS (75%) > B-Fe-PS (63%). Post-degradation UV–Vis absorbance spectra indicated the absence of intermediates in the PS/PMS systems, suggesting complete mineralization of the dye. The kinetics of the process is best described by shifting order rate kinetics. Alkaline pH conditions, low oxidant loading and high initial dye concentration hindered degradation kinetics, while catalyst loading had minimal impact on the oxidation process. The data strongly suggested that biogenic Fe NPs activated oxidant system is an effective alternative to existing hydroxyl – radical based advanced oxidation processes.Graphical abstractGraphical abstract for this article
       
  • Tensile strength of cohesive powders
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Pablo García-Triñanes, Stefan Luding, Hao Shi Measurement and prediction of cohesive powder behaviour related to flowability, flooding or arching in silos is found to be very challenging. Previous round robin [52] attempts with ring shear testers did not furnish reliable data and have shown considerable degrees of scatter and uncertainty in key measurements. Thus studies to build a reliable experimental database using reference materials are needed in order to evaluate the repeatability and effectiveness of shear testers and the adopted procedures.In this paper, we study the effect of particle size on the yield locus for different grades of limestone (calcium carbonate). We use the nonlinear Warren Spring equation to obtain the values of cohesion C, tensile strength T, and the shear index n. We recover linear (n = 1) yield loci for d50>70 μm with respectively small C and T, with consistent, finite macroscopic friction C/T = 0.7. With particle size decreasing below 70 μm the response becomes more and more cohesive and non-linear (1
       
  • Controllable preparation of antimony powders by electrodeposition in
           choline chloride-ethylene glycol
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Jiaojiao Bu, Juanjian Ru, Zhiwei Wang, Yixin Hua, Cunying Xu, Yuan Zhang, Yun Wang Antimony powders with different morphologies have been prepared by electrodeposition at 313–353 K and 10–50 mA·cm−2 in 0.1 mol·L−1 SbCl3 + ChCl-EG solution. The electrochemical behavior of Sb(III) on titanium electrode are studied by cyclic voltammetry. Results show that the electrochemical reduction of Sb(III) in SbCl3 + ChCl-EG solution is a quasi-reversible process via a one-step reaction and the apparent activation energy is 50.723 kJ·mol−1. The effects of current density and temperature on current efficiency and specific energy consumption are also investigated. The current efficiency increases with the increasing of current density and temperature. The specific energy consumption increased with the increase of current density, while decreased with the raising of temperature. When the current density is 40 mA·cm−2 at 353 K, the current efficiency and specific energy consumption are up to 97.89% and 1251.277 kW·h·t−1, respectively. The morphology and phase of the products are analyzed by FESEM and XRD. It demonstrates that the deposition products are pure antimony powders and their preferred crystal plane is (0 1 2). The pineal, wheat grain, badminton, dendritic, and cluster-like antimony powders can be prepared by controlling electrodeposition parameters. The particles size range of antimony powders are 0.21–261.05 μm.Graphical abstractGraphical abstract for this article
       
  • Control of particle charge by atmospheric pressure plasma jet (APPJ): A
           review
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s): Shuji Matsusaka Atmospheric pressure plasma jets (APPJs) have more advantages regarding flexibility of operation than low pressure plasmas. Because the ions and/or electrons in the APPJ can be arbitrarily extracted to a gas-phase space by changing the DC bias voltage and efficiently deposited onto particle surfaces in an external electric field, this operating technique can be applied towards controlling particle charge. Several methods to control the particle charge using an APPJ system have already been reported. This article summarizes the specifications and operations of these systems, their mechanisms of charge transfer, and methods for particle charging, based on previously reported work. The methods are categorized into three groups, i.e., direct charging of particles, direct charging of a powder bed, and indirect charging of particles, and the corresponding experimental setups, procedures, results, and discussions are presented.Graphical abstractGraphical abstract for this article
       
  • Full title (Editorial Board Members)
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s):
       
  • Inside Front Cover (Aims & Scope, Editors)
    • Abstract: Publication date: December 2019Source: Advanced Powder Technology, Volume 30, Issue 12Author(s):
       
  • Approach the powder contact force, voidage, tensile stress, wall
           frictional stress and state diagram of powder bed by simple pressure drop
           monitoring
    • Abstract: Publication date: Available online 15 November 2019Source: Advanced Powder TechnologyAuthor(s): Wan-Yi Hsu, An-Ni Huang, Hsiu-Po Kuo The evaluation of the mechanical properties and the state of a powder bed are essential for industrial powder operations. We assume that the bed incipient yield is approximately the bed incipient fluidization, and the particle contact force, the bed voidage, the bed tensile stress and the bed-wall frictional stress can be determined by simple pressure drop monitoring when gradually increasing the superficial gas velocity from zero. A two-dimensional powder bed voidage-tensile stress state diagram at zero shear stress under anisotropic consolidation is initially prepared. For the sample powder bed, we show that the isotropic tensile stress estimated by the powder yield locus extrapolation, 340 Pa−770 Pa, from a shear tester is different from the anisotropic tensile stress evaluated, 120 Pa–180 Pa, by the pressure drop overshoot approximation.Graphical abstractGraphical abstract for this article
       
  • Numerical investigation on the effect of four constant temperature pipes
           on natural cooling of electronic heat sink by nanofluids: A
           multifunctional optimization
    • Abstract: Publication date: Available online 14 November 2019Source: Advanced Powder TechnologyAuthor(s): Jalal Alsarraf, Amin Shahsavar, Mahsa Khaki, Ramin Ranjbarzadeh, Arash Karimipour, Masoud Afrand In the present study, natural-convective heat transfer along with the effects of radiation of aluminum/water nano-fluid between two blades of a heat sink, which is under the impact of a uniform magnetic-field, is studied numerically. The space between two blades of the heat sink is considered as a two-dimensional square enclosure. In the square cavity, there are four pipes with constant temperature Th with a circular cross section. The RSM method is used to optimize the geometric parameters of the pipes. The results show that the heat transfer rate from the pipes and the irreversibility generation augment and the Bejan number reduces by augmenting the Rayleigh number. The heat transfer intensified 7% and 16% by doubling of the aspect ratio of the pipes at the Rayleigh number of 103 and 106, respectively. As the distance between constant-temperature pipes intensified, Nusselt number augments. As the horizontal enclosure rotates 90°, i.e., it becomes a vertical enclosure, the heat transfer decreases by 22% and total irreversibility decreases by 21%. The optimum physical conditions of the pipes are is in the diameter of 0.15 and 0.25 of distance from each other to have maximum heat transfer and the minimum irreversibility generation.Graphical abstractGraphical abstract for this article
       
  • Spray drying strategy for encapsulation of bioactive peptide powders for
           food applications
    • Abstract: Publication date: Available online 13 November 2019Source: Advanced Powder TechnologyAuthor(s): Yong Wang, Cordelia Selomulya Spray drying is commonly used to manufacture food and dairy powders at industrial scale. Bioactive peptides, as hydrolysis products from various food proteins, are gaining interest due to their biological functionality including immunomodulation, antimicrobial, and antioxidant properties. This article reviews several bioactive peptides/hydrolysates from different food sources, focusing on their processing and final powder characteristics. Additionally, we propose a strategy for encapsulation of food peptide/hydrolysate via spray drying. The identification of suitable drying parameters and/or formulation could help overcome the limitations associated with the current processing of food peptides.Graphical abstractGraphical abstract for this article
       
  • Fabricating mono-dispersed Fe3O4-SiO2 core-shell particles with help of
           triboelectrification
    • Abstract: Publication date: Available online 13 November 2019Source: Advanced Powder TechnologyAuthor(s): Ji Ma, Kezheng Chen For years, it has been widely held that triboelectrification is not the sought-after technique to develop innovative materials with enhanced functionalities. In this study, we tried to break such a traditional concept and find its ever-expanding roles in material science. In our strategy, triboelectrification brought adequate charge to particles, so as to achieve their mono-dispersity in solutions. Following this strategy, the synthesis of mono-dispersed Fe3O4-SiO2 core-shell particles involved two-stage triboelectrification treatment. In the first-stage treatment, positive triboelectric charges on Fe3O4 cores ensured their uniform SiO2 coating and well-defined core-shell structure. In the second-stage treatment, positive triboelectric charges on Fe3O4-SiO2 core-shell particles guaranteed their mono-dispersity for further biological use. The Zeta potential of these triboelectrically-treated Fe3O4-SiO2 core-shell particles still maintained at ca. +55 mV after standing for two months, and their conglomeration was negligible owing to their limited increase in hydrodynamic size. Besides, their excellent linearity between relaxivities and iron concentration, and their virtually unchanged r2/r1 ratio within two months manifested that triboelectrification can be a promising technique in fabricating advanced materials.Graphical abstractGraphical abstract for this article
       
  • Magnetically recoverable catalyst based on porous nanocrystalline HoFeO3
           for processes of n-hexane conversion
    • Abstract: Publication date: Available online 13 November 2019Source: Advanced Powder TechnologyAuthor(s): K.D. Martinson, I.S. Kondrashkova, S.O. Omarov, D.A. Sladkovskiy, A.A. Kiselev, T.Y. Kiseleva, V.I. Popkov Nowadays, a wide class of rare earth orthoferrites is of great interest among acid-base catalysts due to their high activity and the possibility of magnetic recovery. However, the synthesis of chemically and phase-pure rare-earth orthoferrites in the form of nanocrystals with developed surface and microstructure is still a difficult task. In this work, we report for the first time a successful synthesis of phase-pure holmium orthoferrite (HoFeO3) nanocrystals with a porous microstructure and a branched surface via simple glycine-nitrate combustion approach. Holmium orthoferrite nanocrystals were characterized by using energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), 57Fe Mössbauer spectroscopy and low-temperature sorption-desorption of nitrogen. Acid-base properties of the surface and catalytic activity of porous HoFeO3 in process of n-hexane conversion were analyzed as well. Finally, a magnetic recovery procedure was performed for the spent catalyst to analyze its efficiency for synthesized HoFeO3. The elemental composition of the sample corresponds to holmium orthoferrite (48.8 and 51.2 at. %, for Ho and Fe, respectively) with the absence of any impurities as it was shown by EDX. The PXRD results show that the synthesized HoFeO3 nanocrystals have an orthorhombic structure (space group Pbnm) and an average crystallite size of 62 ± 5 nm. The Rietveld method was used to refine the unit cell parameters as follows: a = 5.254(1) Å, b = 5.575(3) Å, c = 7.598(4) Å; Rwp = 2.45%. The Mössbauer spectrum of HoFeO3 evidenced the magnetically ordered state of nanocrystals and it is represented by a sextet with quadrupole splitting (QS), of 0 mm/s, an isomeric shift (IS) of 0.36 mm/s, and an effective magnetic field (Heff) of 497 kOe. Sorption-desorption of nitrogen shows that the holmium orthoferrite has a predominantly macro- and mesoporous structure, also confirmed by SEM, with specific surface area and total porosity values of 31 m2/g and 0.071 cm3/g, respectively. The analysis of the acid-base properties of the surface of the porous HoFeO3 evidences a high concentration of the aprotic (Lewis) acidic (pKa = 14.2) and basic (pKa = -4.4) sites, as well as of the Brønsted weak acid (pKa = 6.4) sites. The catalytic activity of holmium nanocrystalline in process of n-hexane conversion was analyzed and compared with commercial dehydrogenation (CD-1) and cracking (ZSM-5) catalysts. The n-hexane conversion and cracking products selectivity displayed by HoFeO3 are comparable to those of the reference catalysts, and the selectivity to dehydrogenation and especially isomerization products significantly exceeds the values of CD-1 and ZSM-5; low n-hexane oligomerization product selectivity of HoFeO3 catalyst was observed as well. A high recovery rate (∼97%) achieved as a result of the magnetic separation of the spent o-HoFeO3-based catalyst from the reaction mixture, followed by heat treatment at 600 °C for 1 h. These results allow us to conclude that synthesized porous HoFeO3 can be considered as a promising basis for new catalytic materials for cracking, dehydrogenation and isomerization processes with a possibility of highly efficient magnetic recovery.Graphical abstractThe procedure aimed at synthesis of porous o-HoFeO3 nanocrystals by solution combustion method was elaborated. It was found that the degree of selectivity of holmium ferrite in n-hexane conversion into paraffins (28%) and olefins (34%) is at the level with commercial catalysts.Graphical abstract for this article
       
  • Synthesis and photocatalytic activity of BiOCl/diatomite composite
           photocatalysts: Natural porous diatomite as photocatalyst support and
           dominant facets regulator
    • Abstract: Publication date: Available online 9 November 2019Source: Advanced Powder TechnologyAuthor(s): Min Yi Liu, Liang Zheng, Guo Liang Lin, Liu Fang Ni, Xu Chun Song BiOCl/diatomite composite with enhanced photocatalytic property for the degradation of liquid Tetracycline hydrochloride (TC) and gaseous formaldehyde (HCHO) were successfully prepared by a facile hydrothermal method at different pH value. The structure and morphology characterizations of BiOCl/diatomite composite exhibit that diatomite not only acts as a natural porous support of photocatalyst but also acts as dominant facets regulator at pH = 3 when the doping amount is change, owing to the surface electrical property of the diatomite and interaction between diatomite and BiOCl. This interaction is certified by XPS and FT-IR which indicate that Bi in layer structure of [Bi2O2]2+ group interacts with the O in SiOSi bond when the formation of BiOCl with the participation of diatomite. The BET characterization confirms that the increasing amount of diatomite enables the composite with more reaction points for light harvest and molecule adsorption than pure BiOCl. Furthermore, TC and formaldehyde are targeted as degradation objects to test the photocatalytic property of BiOCl/diatomite composite. The optimum photocatalytic property are BiOCl(3–1.2) and BiOCl(12–0.6) at TC degradation and BiOCl(3–0.3) and BiOCl(12–0.6) at formaldehyde elimination, which is much better than that of pure diatomite or BiOCl. The difference of optimum photocatalysts in liquid and gaseous phase systems can be attributed to the photoelectric performances of BiOCl/diatomite composite, which were characterized by DRS, PL, transient photocurrents and the electrochemical impedance spectroscopy technique.Graphical abstractGraphical abstract for this article
       
  • Dispersion of amorphous silica nanoparticles via beads milling process and
           their particle size analysis, hydrophobicity and anti-bacterial activity
    • Abstract: Publication date: Available online 7 November 2019Source: Advanced Powder TechnologyAuthor(s): I. Made Joni, M. Vanitha, C. Panatarani, F. Faizal In this present work, amorphous silica is synthesized by simple solution method using sodium silicate (Na2SiO3) as raw material. The synthesized silica is dispersed in various dispersing agent obtained from local paint industry and used for painting application. XRD analysis revealed the existence of amorphous silica with a peak at 2θ value of 23° and the SEM analysis exemplified silica nanoparticles demonstrating spherical morphology with agglomeration. Different dispersing agents (as indicated by the codes given by paint industry) were used for the dispersion of SiO2 by beads milling process and its effects were studied. Among the several dispersing agents used amorphous silica dispersed in SND 504 (Sodium salt of polymeric carboxylic acid with water) dispersing agent exhibit better dispersion compared to the other dispersing agents. Further, 10 wt% of SND 504 dispersing agent was optimized with the particle size to 384 nm and zeta potential value of −24.69 mV. The contact angle measurement of the dispersed silica reveals the superior hydrophobic behaviour of SiO2, especially with 10 wt% SND 504 dispersing agent. The critical surface tension of SiO2 with 10 wt% SND 504 dispersing agent reveal low value compared to other concentration of dispersant. Thus, the dispersed silica nanoparticles with enhanced hydrophobicity can be effectively used for painting applications as fillers. Silica dispersed in 10 wt% SND 504 dispersing agent show superior anti-bacterial activity compared to the bare silica which is also reported.Graphical abstractGraphical abstract for this article
       
  • Simplified model for particle collision related to attrition in pneumatic
           conveying
    • Abstract: Publication date: Available online 7 November 2019Source: Advanced Powder TechnologyAuthor(s): Dmitry Portnikov, Nir Santo, Haim Kalman This paper presents a simple method for predicting particle attrition during pneumatic conveying. The model calculates the changes in the particle size during pneumatic conveying (as a result of the collisions between the particles and bend walls) by using empirical correlations for both the machine and material functions. The method does not require the use of complicated simulations such as DEM–CFD. Furthermore, the computational model was written in MATLAB, and the results agree well with the experimental results for salt particles. The computation time was very short: a few seconds for the first collision (particles passed through one bend), and below one minute for six collisions. The experimental results and parametric study show that higher bend radius ratios caused less damage to the conveyed material. Moreover, higher air velocities and larger pipe diameters caused more damage to the conveyed material.Graphical abstractGraphical abstract for this article
       
  • Bi4TaO8Cl/Graphene nanocomposite for photocatalytic
           water splitting
    • Abstract: Publication date: Available online 7 November 2019Source: Advanced Powder TechnologyAuthor(s): Hadi Razavi-Khosroshahi, Sara Mohammadzadeh, Masayoshi Fuji Sillen-Aurivillius structures like Bi4NbO8Cl, Bi4TaO8Cl, and Bi4TaO8Br have been expected as efficient visible light active photocatalysts thanks to their narrow band gaps less than 2.5 eV and suitable negative conduction band potential for hydrogen production reaction, 0.0 V vs NHE. However, despite their excellent potential the photocatalytic hydrogen generation efficiency of them under visible light has remained low. The low activity is usually attributed to the shallow defect levels near the conduction band, causing fast recombinations of photoexcited electrons and holes. In this study, a nanocomposite of Bi4TaO8Cl and graphene is proposed for overcoming this issue. The excellent electron conductivity and abundant delocalized electrons from the conjugated sp2-bonded carbon networks in graphene can facilitate the transfer of electrons from Bi4TaO8Cl conduction band and increase the photocatalytic efficiency. Bi4TaO8Cl/graphene nanocomposite was successfully prepared by a hydrothermal method, and photocatalytic activity enhanced both under UV and visible light.Graphical abstractGraphical abstract for this article
       
  • Impact of process flow conditions on particle morphology in metal powder
           production via gas atomization
    • Abstract: Publication date: Available online 6 November 2019Source: Advanced Powder TechnologyAuthor(s): D. Beckers, N. Ellendt, U. Fritsching, V. Uhlenwinkel Additive manufacturing processes as for instance selective laser melting or electron beam melting are becoming more common and just turning into standard manufacturing processes for metal components. Nevertheless, these processes are still new compared to classic powder metallurgy manufacturing routes such as pressing and sintering. Hence not all necessary requirements for the powders in use are fully known yet. This makes an increase in control of the powder properties a crucial task to achieve. To reach this goal one must understand the different influences on the powder production process from the beginning of the whole production route. In this work, the influence of the spray chamber flow on the particle morphology is examined. The nozzle system used to produce the metal powders is a close-coupled atomization system with a convergent-divergent gas nozzle configuration. The particle morphology as well as the particle size distribution have been analyzed to examine the influence of the atomization gas flow compared to an additional use of a coaxial gas flow. To review the changes of the flow patterns, computational fluid dynamic simulations have been performed. The particle trajectories were calculated to assess the change in particle behavior as well. Atomization experiments have been conducted with an AISI 52100 (1.3505) steel in a small batch atomization plant to evaluate the influence of the change in flow on the particle size distribution and circularity. The experimental results show that a use of additional coaxial gas leads to an increase in particle circularity up to 10% for relevant particle sizes. An approach for the quantification of satellite occurrence is given by examination of the shift of the particle size distribution to smaller diameters.Graphical abstractGraphical abstract for this article
       
  • Numerical simulation of semi-dry flue gas desulfurization process in the
           powder-particle spouted bed
    • Abstract: Publication date: Available online 6 November 2019Source: Advanced Powder TechnologyAuthor(s): Feng Wu, Kai Yue, Weiwei Gao, Ming Gong, Xiaoxun Ma, Wenjing Zhou Computational fluid dynamics (CFD) combined with the two-fluid model (TFM) was used for simulation of water vaporization and semi-dry flue gas desulfurization process in a two dimensional powder-particle spouted bed (PPSB), on the basis of gas-solid two-phase flow, the mathematical and physical models of water vaporization process and flue gas desulfurization reaction process have been established through reasonable hypothesis and simplification of the system. The numerical method was used to simulate the desulfurization reaction process and the heat and mass transfer in the powder-particle spouted bed. Simulation results indicate that water vaporization rate was high in spout and annular regions. The main area where flue gas desulfurization reaction occurs was annular area, as a result, the maximum value of desulfurization product rate appears in the annulus. Under the same condition, the desulfurization efficiency of simulation value is 75.75% when the value of slurry water content equals 40 kg-H2O/kg-dry_sorbent, which is close to but greater than the experimental value (75.03%). The desulfurization efficiency of spouted bed increases first and then decreases with the increase of water content of desulfurization slurry, and the optimum slurry water content for desulfurization process in powder-particle spouted bed was obtained by numerical simulation, which was 40 kg-H2O/kg-dry_sorbent.Graphical abstractGraphical abstract for this article
       
  • The control of paracetamol particle size and surface morphology through
           crystallisation in a spray dryer
    • Abstract: Publication date: Available online 6 November 2019Source: Advanced Powder TechnologyAuthor(s): Alan F. McDonagh, Lidia Tajber The parameters governing the crystallisation of paracetamol using various conventional techniques has been extensively studied, however the factors influencing the drug crystallisation using spray drying is not as well understood. The aim of this work was to investigate the crystallisation of an active pharmaceutical ingredient through evaporative crystallisation using a spray dryer to study the physicochemical properties of the drug and to use semi-empirical equations to gain insight into the morphology and particle size of the dried powder. Paracetamol solutions were spray dried at various inlet temperatures ranging from 60 °C to 120 °C and also from a series of inlet feed solvent compositions ranging from 50/50% v/v ethanol/water to 100% ethanol and solid-state characterisation was done. The size and morphology of the dried materials were altered with a change in spray drying parameters, with an increase in inlet temperature leading to an increase in particle Sauter mean diameter (from 3.0 to 4.4 µm) and a decrease in the particle size with an increase in ethanol concentration in the feed (from 4.6 to 4.4 µm) as a result of changes in particle density and atomised droplet size. The morphology of the dried particles consisted of agglomerates of individual crystallites bound together into larger semi-spherical agglomerates with a higher tendency for particles having crystalline ridges to form at higher ethanol concentrations of the feed.Graphical abstractGraphical abstract for this article
       
  • Modification of the Vipulanandan rheological model with correlation for
           temperature and electrolyte effect on drilling muds
    • Abstract: Publication date: Available online 6 November 2019Source: Advanced Powder TechnologyAuthor(s): Richard O. Afolabi, Esther O. Yusuf Modelling the flow of drilling muds requires the use of existing generic time-independent models with a number of parameters incorporated. While these parameters quantify the uncertainties surrounding the mud rheology, the tuning of each parameter for proper flow description can be challenging and time consuming. As such, the introduction of new parameters in describing additional reservoir conditions associated with drilling muds would only increase the complexity of the computational process. Therefore, the predictive capability of applied rheological models for the different flow regimes and reservoir conditions associated with drilling muds is still limited in scope. Existing procedure using generic rheological models would give a generalized approach to computing the performance of drilling muds when taking into account new factors such as temperature and electrolyte effects. Therefore, there is need to accurately model the rheology of drilling muds taking into account new conditions without necessarily introducing new fitting parameters to a particular model. In this work, a novel approach was employed where the time constant of the modified Vipulanandan model was related to reservoir conditions without introducing a new fitting constants or parameters. The selection of the Vipulanandan model among others was based on the conditions stated by Vipulanandan and Mohammed (2014) and the use of statistical validation tools based on best fit. Moreover, the Vipulanandan model represents the only model which can be modified to have a time constant in it.Graphical abstractGraphical abstract for this article
       
  • Analysis of densification mechanisms of dry granulated materials
    • Abstract: Publication date: Available online 6 November 2019Source: Advanced Powder TechnologyAuthor(s): S. Uniyal, L.P. Gandarillas, M. Michrafy, D. Oulahna, A. Michrafy Dry granulation by roll compaction is a continuum manufacturing process to produce granules with improved flowability which can further be easily used in tableting process. However, the granules are non-homogeneous in density and have non-spherical shapes which impact their densification behaviour during die-compaction. The aim of this study was to investigate both the densification mechanism and the failure strength of granules of microcrystalline cellulose (MCC) and mannitol using Cooper-Eaton and Adams models. For both materials, the Cooper-Eaton approach led to the quantification of fractional volume compaction by particle rearrangement and by plastic deformation respectively to explain the difference in densification behaviour of raw material and granules. Moreover, the model showed its ability to capture the effect of granule density and granule sizes and to differentiate the densification mechanisms of MCC as a plastic material and mannitol as a brittle material. The Adams model was used to compute the failure strength of single granule from in-die compression data. The obtained results of the granules were in the range [0.6–1.43 MPa]. However, regarding the effect of granule density, the model showed mixed results indicating that the model is not representative of the studied granules which are not spherical and have a relatively wide range of sizes, nevertheless, the model was derived for near spherical particles with a narrow size distribution.Graphical abstractGraphical abstract for this article
       
  • Steel slag waste combined with melamine pyrophosphate as a flame retardant
           for rigid polyurethane foams
    • Abstract: Publication date: Available online 5 November 2019Source: Advanced Powder TechnologyAuthor(s): Gang Tang, Xinliang Liu, Lin Zhou, Ping Zhang, Dan Deng, Haohao Jiang To explore the potential application of industrial waste, steel slag powder in combination with melamine pyrophosphate (MPP) was adopted to improve the flame retardancy of rigid polyurethane foam (RPUF). The incorporation of steel slag slightly reduced the thermal conductivity of the resulting flame-retardant RPUF samples. The addition of MPP and/or steel slag did not significantly alter the thermal stability in terms of T-10% and Tmax but did obviously increase the T-50% value, suggesting the improved thermal resistance of the residues. The coaddition of MPP and steel slag into RPUF resulted in higher LOI values and lower peak heat release rates than the samples incorporating either MPP or steel slag alone. The superior flame retardancy could be attributed to MPP promoting char formation, which then acted as a barrier at the beginning of RPUF thermal decomposition; simultaneously, the thermally stable inorganics in the steel slag powder strengthened the thermal resistance of this char layer.Graphical abstractGraphical abstract for this article
       
  • Surfactant assisted synthesis of precipitated calcium carbonate
           nanoparticles using dolomite: Effect of pH on morphology and particle size
           
    • Abstract: Publication date: Available online 2 November 2019Source: Advanced Powder TechnologyAuthor(s): M.R. Abeywardena, R.K.W.H.M.K. Elkaduwe, D.G.G.P. Karunarathne, H.M.T.G.A. Pitawala, R.M.G. Rajapakse, A. Manipura, M.M.M.G.P.G. Mantilaka Synthesis of nanomaterials from readily available minerals for industrial applications is a growing research area. Understanding the causes of their properties becomes handy in utilization. In this study, an effective sucrose solution based method was employed for the extraction of calcium from dolomite to synthesize precipitated calcium carbonate nanostructures with different morphologies and sizes. It was found that 30% (w/v) sucrose solution extracted approximately 91% of calcium from dolomite forming a calcium-sucrate complex. Carbonation was achieved by CO2 bubbling and aqueous sodium carbonate addition. Precipitation was performed under different pH values of 7.5, 10.5 and 12.5 in the absence of an anionic surfactant and in the template of sodium dodecyl sulfate (SDS)/calcium-sucrate at pH 12.5. It was found that CO2 bubbling slightly promotes smaller particles. The anionic surfactant enables particle size and agglomeration reduction while introducing some hydrophobicity. The smallest particles were achieved at a range of 40–55 nm in the presence of SDS/sucrose template and were of spherical morphology. By changing the pH, a tendency to form different polymorphs and shapes of calcium carbonate was observed.Graphical abstractGraphical abstract for this article
       
  • Experimental investigation on the packed bed of rodlike particles
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Wenguang Nan, Yueshe Wang, Houhuan Sun Rodlike particles have been usually found in industrial applications, such as the straw and needle catalyst in energy and chemical engineering. Compared to spherical particles, rodlike particles exhibit different behaviour in the packing structure due to their rotational movement. In this work, we have experimentally explored the packing structure and its friction factor for fluid flow. The porosity of packing structure generated by two packing methods is measured for four kinds of rodlike particles. The experimental results show that the porosity of bed of rodlike particles in the poured packing is not a monotonic function of the aspect ratio of particles. This is due to the competition between the “self-fitting” effect and excluded effect. The porosity of bed of rodlike particles is more sensitive to the packing method than that of spherical particles. To describe the pressure drop of fluid flow through the packing structure, the Ergun equation is further modified by introducing the modified Reynolds number and Galileo number. By combing the experimental data for packed bed generated by the fluidised packing method, and other experimental work in current literature, a new empirical equation is proposed to predict the friction factor of the packing structure of rodlike particles, in which the effects of the particle orientation and particle shape are both considered by the equivalent sphericity. These experimental results would be of interest from applied standpoints as well as revealing fundamental effects of the aspect ratio of rodlike particles on the packing structure.Graphical abstractGraphical abstract for this article
       
  • Experimental investigation of fluidized bed dynamics under resonant
           frequency of sound waves
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Ebrahim H. Al-Ghurabi, Syed Sadiq Ali, Sulaiman M. Alfadul, Mohammed Shahabuddin, Mohammad Asif Sound-assisted fluidization has of late gained a significant research focus as a potential assisted fluidization technique for improving the hydrodynamics of solids that exhibit cohesive and non-homogeneous fluidization behavior. This study investigated the dynamics of a bed subjected to acoustic perturbations at different frequencies during the sound-assisted fluidization of a hydrophilic nanopowder with strong agglomeration behavior. The bed pressure transients were carefully monitored using sensitive pressure transducers in different sections of the bed over a wide range of velocities using ambient air as the fluidizing gas. Both fluidization and defluidization dynamics were investigated by varying the velocity in small steps using electronic mass flow controllers connected to a data acquisition system. In addition to the resonance frequency of 220 Hz, acoustic vibrations of 200 and 150 Hz frequency were also investigated to clearly delineate the effect of resonant frequency on the bed response. Our results clearly suggest that operation of sound-assisted fluidization at the resonant frequency greatly enhances its effectiveness.Graphical abstractGraphical abstract for this article
       
  • Microstructural and morphological changes during ball milling of
           Copper-Silver-Graphite flake mixtures
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): A. Pragatheeswaran, Rahul Ravi, Srinivasa Rao Bakshi The present study reports the microstructural and morphological changes during high energy ball milling of Cu with Ag and Graphite flakes. XRD patterns of ball milled Cu-Ag showed a reduction in the intensity of Ag peaks (1 1 1) and an increase in the lattice parameter of Cu. With an increase in milling time, the formation of metastable Cu-Ag solid solution was observed. Lattice parameter values for 40 h milled Cu (3.6169 Å) and Cu-GF composites (3.6166 Å) indicated that C does not dissolve in Cu. The lattice parameter of Cu in milled Cu-Ag-graphite flake was lower compared to milled Cu-Ag mixture indicating that graphite flakes inhibit solid solution formation. Raman spectra revealed that graphite flakes were converted into multilayer graphene after 10 h of milling. The crystallite size of Cu in the milled powders decreased with increase in milling time and reached a value of ∼25 nm after 35 h of milling. The lattice strain also increased with milling time. The D10, D50 and D90 size reduced appreciably after 5 h of milling.Graphical abstractGraphical abstract for this article
       
  • Facile electroless copper plating on diamond particles without
           conventional sensitization and activation
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Chenlong Wei, Jigui Cheng, Pengqi Chen, Bangzheng Wei, Dalu Gao, Dang Xu Conventional electroless plating of copper on diamond particles needs SnCl2 sensitization and PdCl2 activation pretreatments, which needs noble metal and consumes a large amount of reducing agent. In this paper, metallic tungsten coatings were first plated onto diamond particles by microwave-heating salt-bath plating (MHSBP) method, and then copper layer was directly plated onto the out surface of the tungsten layer by an electroless plating method with no need of SnCl2 sensitization and PdCl2 activation pretreatments. Composition and morphology of the coatings was analyzed by XRD, SEM, and EDS. The results show that the copper coating on the diamond surfaces can be adjusted by control the concentration of CuSO4·5H2O and plating temperature, and a full copper coating is achieved with content of CuSO4·5H2O of 19.6 g/L in the plating solution at 60 °C. The bending strength of the coated diamond/Cu composites is as high as 630 MPa, which increases 93.3% than the uncoated composites. This work presents an electroless plating of copper can directly on the surfaces of diamond particles with no need of conventional sensitization and activation, and a strong interface combination between coated diamond and copper.Graphical abstractThe surfaces of the tungsten-coated diamonds have a lot of defects and can be successfully coated by Cu particles by using eletroless plating without sensitization and activation. This process is not only simple, but also obtains a strong interface force between diamond and copper.Graphical abstract for this article
       
  • NiAl-B composites with nanocrystalline intermetallic matrix produced by
           mechanical alloying and consolidation
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Marek Krasnowski, Stanislaw Gierlotka, Tadeusz Kulik Powder mixtures with equiatomic Ni–Al stoichiometry and with the addition of 5, 10, 20 and 30 vol% of boron were mechanically alloyed in a high-energy SPEX mill. Differential scanning calorimetry (DSC) was used for examination of the thermal behaviour of the milled powders. The mechanically alloyed powders and powders after DSC examinations were investigated by X-ray diffraction (XRD). For all the powder mixtures, a nanocrystalline NiAl intermetallic phase was formed during milling. With the increase of boron concentration in the mixtures, more intense refinement of the NiAl grain size during mechanical alloying was observed. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) examinations showed that the produced powders have composite structure, with boron particles uniformly distributed in the nanocrystalline NiAl intermetallic matrix. The density of the composite powders decreases with the increase of boron content, following the rule of mixture.The produced powders were subjected to consolidation by hot-pressing at 800 °C under the pressure of 7.7 GPa for 180 s. The produced bulk materials were investigated by XRD, SEM and EDS as well as characterised by hardness, density and open porosity measurements. It was found that during applied consolidation process the nanocrystalline structure of the NiAl matrix was maintained. The average hardness of the bulk composite samples is in the range of 10.58–12.6 GPa, depending on boron content, increases with the increase of boron content, and is higher than that of the NiAl intermetallic reference sample (9.53 GPa). The density of the bulk composite samples is the same as that of the corresponding powders after milling, decreases with the increase of boron content and is lower than that of the NiAl reference sample. To the best of our knowledge, the NiAl-B composites with nanocrystalline intermetallic matrix have been produced for the first time.Graphical abstractGraphical abstract for this article
       
  • Synthesis and humidity control performances of natural opoka based porous
           calcium silicate hydrate
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Yangyu Liu, Hongwei Jia, Guangxin Zhang, Zhiming Sun, Yongtai Pan, Shuilin Zheng In this work, a porous calcium silicate hydrate (CSH) humidity control material was prepared by hydrothermal synthesis with opoka (ROP) and slaked lime. The microstructures and humidity control properties of the prepared sample were characterized and analyzed in detail. Results show that CSH possesses plenty of mesoporous structures with the pore size range of 3–20 nm, which are superior to ROP. The maximum moisture adsorption capacity of CSH is about 2–3 times of ROP. The superior humidity control performance of CSH can be attributed to the increase of specific surface area and pore volume and the more reasonable and uniform pore size distribution. Moreover, CSH also exhibits good reusability within three cycles of adsorption/desorption. Furthermore, the synthesized CSH was added to an interior wall coating to test its humidity control performance in practical building materials. The result indicated that the moisture adsorption capacity of the coating with CSH in 24 h at high humidity can reach 110 g/m2, and the moisture desorption capacity can also reach 70 g/m2. The as received CSH shows excellent humidity control performance and can be used as a smart indoor humidity control material for various construction applications.Graphical abstractGraphical abstract for this article
       
  • Numerical simulation of high-pressure gas atomization of two-phase flow:
           Effect of gas pressure on droplet size distribution
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Kalpana Hanthanan Arachchilage, Majid Haghshenas, Sharon Park, Le Zhou, Yongho Sohn, Brandon McWilliams, Kyu Cho, Ranganathan Kumar This paper deals with the physics of high-pressure gas atomization in metal powder production. To gain understanding of the effect of gas pressure on droplet size distribution, a numerical two-phase flow study is performed using Eulerian-Eulerian Volume of Fluid (VOF) interface tracking method. Annular-slit, close-coupled gas atomizer is considered to atomize molten aluminum using nitrogen as the atomizing gas. Four cases with different gas pressures are considered, while geometry and other operational parameters are fixed. Characteristics of several interfacial instabilities have been identified at different stages of the atomization process. Despite the increment in the rate of the atomization with the increasing gas pressure, deformation characteristics and the breakup mechanisms remain unchanged. Droplet size and the cumulative volume distributions indicate that the effectiveness of the atomization process increases with the elevating gas pressure. Cumulative volume obtained from the numerical simulations at low gas pressures display similar trends to the experimental results.Graphical abstractGraphical abstract for this article
       
  • CPFD simulation on effects of louver baffles in a two-dimensional
           fluidized bed of Geldart A particles
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Zhijun Yang, Yongmin Zhang, Hongna Zhang Numerical simulation based on computational particle fluid dynamics (CPFD) model was carried out in a two-dimensional fluidized bed of Geldart A particles which was previously used by Zhang et al. (2009) to study the effects of louver baffles on bed hydrodynamics and gas mixing. With the help of bubble-based energy-minimization multi-scale (EMMS) drag model, the simulation successfully predicted most of the hydrodynamic results which were highly agreeable with experimental results. However, gas tracing simulation was found to depart far from experimental results due to lack of modeling of porous structure of FCC particles. A direct method to characterize solids back-mixing strength based on the simulated internal circulation fluxes was established. The results not only proved the strong suppression of solids back-mixing by louver baffles, but also validated the feasibility of the two indirect measures used in the previous experiment to characterize solids back-mixing strength. Louver baffles’ ability to break up bubbles was also proved. Under low superficial gas velocities, their vanes can split bubbles directly. However, it acts as a distributor under high superficial gas velocities.Graphical abstractGraphical abstract for this article
       
  • Densification of pure magnesium by spark plasma sintering-discussion of
           sintering mechanism
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Ruifeng Liu, Wenxian Wang, Hongsheng Chen, Zhen Lu, Wei Zhao, Tingting Zhang In this study, high-quantity pure magnesium was prepared by SPS, and the sintering densification mechanism was discussed by using numerical simulation and simultaneous experiment. Results show that a layer of dense magnesium oxide was formed at the surface of Mg particles, and the oxide reduction can be observed owing to the effect of oxide film removal in SPS. The high energy pulsed current flows preferentially through particle contact surfaces, which provides the conditions for the generation of micro-arc between particles and the temperature at the particles contact point can be up to 1979 °C. With the low pressure at the initial sintering stage, local high temperature induced by micro-arc makes the melting (even evaporation) appearance. At the same sintering temperature of 570 °C, the obvious difference in bending strength also demonstrates the significance of spark discharge in SPS. The formation process of sintering neck demonstrates that sintering process is the reflection of melting (even evaporation), diffusion and plastic deformation. In order to realize tiny area and high-quality connection between powder particles, an innovative powder sintering technology using high-frequency pulse electric current (High frequency pulse current assisted sintering) is proposed based on the enlightenment of the skin, proximity and arc discharge effect of high-frequency pulse current. This technology is also instructive for other alloys and engineering materials.Graphical abstractGraphical abstract for this article
       
  • Robust green synthetic approach for the production of iron oxide nanorods
           and its potential environmental and cytotoxicity applications
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): K. Ramar, A. Jafar Ahamed, K. Muralidharan A facile and eco-friendly green method has been developed for the synthesis of hematite nanorod-like architecture (G-Fe2O3 NRs) using the resin obtained from the stem of the banana flower (Musa Paradisiaca Linn). In this green hydrothermal synthesis, the resin played dual roles as oxygen source and as structure directing stabilizing agents, which followed the facile one-step process, and it is suitable for scaling up to large-scale synthesis. Various techniques were used to investigate the physicochemical properties such as structural, morphological, surface area, thermal, magnetic, band gap and lifetime properties of the green synthesised G-Fe2O3 NRs. Investigations of G-Fe2O3 NRs by electron microscopes showed the average length and girth of the NRs were ranging from 528 ± 173 nm and 72 ± 21 nm. Significant impact on the physicochemical properties by this green synthetic approach yielded concrete results in their catalytic activities overcoming major environmental concerns. Especially, our green catalyst showed better redox kinetics with the lesser over potential than the commercially available bulk counterparts upon evaluating the photoelectrochemical water splitting ability such as oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Moreover, the photocatalytic efficiency of G-Fe2O3 NRs was evaluated by solar induced photoreduction of dichromate [toxic hexavalent chromium Cr(VI) to sustainable harmless trivalent chromium Cr(III)] and degradation of malachite green (MG). Both the processes involve the photocatalytic conversion by sequential adsorption of analytes on mineral surface and the overall efficiency was achieved mainly due to the high surface area (59.87 m2/g) of the catalyst. The cytotoxicity studies indicate that G-Fe2O3 NRs possesses much potential to work against A-549 (lung cancer) cell line.Graphical abstractGraphical abstract for this article
       
  • Characterization of mechanically alloyed and pressureless sintered
           Al-7 wt% Si-2 wt% LaB6-2 wt% (MoSi2, WSi2) hybrid composites
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Emre Tekoğlu, Yakup Yürektürk, Duygu Ağaoğulları, Didem Ovalı, Sıddıka Mertdinç, M. Lütfi Öveçoğlu The purpose of this research is to investigate the dual effect of silicide (MoSi2 or WSi2) and LaB6 reinforcing particles on the microstructural and mechanical properties of Al-7 wt% Si (Al7Si) matrix. Hypoeutectic Al7Si blends prepared from elemental Al and Si powders were mechanically alloyed (MA’d) for 12 h in a planetary ball mill (at 300 rpm). Afterwards, 2 wt% silicide reinforcements (MoSi2 or WSi2) with various particle size distributions (micron, bimodal, submicron) were separately added into these MA’d Al7Si powders together with 2 wt% of LaB6 particles. Powders having compositions of Al7Si, Al7Si-2 wt% LaB6, Al7Si-2 wt% LaB6-2 wt% MoSi2 and Al7Si-2 wt% LaB6-2 wt% WSi2 were milled for 30 min using a high-energy ball mill (at 1200 rpm) in order to obtain homogeneous distribution throughout the microstructure. Compositional, microstructural and mechanical characterization studies were performed on the sintered samples. The results showed that high-energy ball milling ensured the homogeneous distribution of micron-sized MoSi2 and WSi2 particles within the matrix rather than those of bimodal and submicron-sized ones. Micron-sized MoSi2 and WSi2 reinforced hybrid composites displayed dramatically higher hardness and wear resistance than those of composites reinforced with different size of MoSi2 and WSi2 particles. The striking point of the study was the remarkably higher hardness and wear resistance properties of the hybrid composites compared to those of un-reinforced and only LaB6-reinforced ones. As a conclusion, hybrid composites extremely displayed promising mechanical properties.Graphical abstractGraphical abstract for this article
       
  • Ion reduction in iron oxide and oxyhydroxide nanoparticles during
           ultrasonic treatment
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): S.V. Stolyar, O.A. Bayukov, R.N. Yaroslavtsev, Yu.V. Knyazev, V.P. Ladygina, Yu.V. Gerasimova, R.S. Iskhakov The effect of ultrasonic treatment of iron oxide and iron oxyhydroxide nanoparticles (ferrihydrite nanoparticles synthesized by Klebsiella oxytoca microorganisms, ferrihydrite nanoparticles synthesized by a chemical method and hematite nanoparticles) is studied. Samples of nanoparticles were investigated using transmission electron microscopy, Mössbauer spectroscopy and X-ray diffraction methods. The formation of the α-Fe metal phase from nanoparticles of iron oxides and iron oxyhydroxides was detected. The metal phase is formed as a result of the reduction of iron ions during cavitation treatment. According to the experimental results, the presence of a protein or a polysaccharide component is necessary for the course of this reaction.Graphical abstractGraphical abstract for this article
       
  • Simulation analysis and engineering application of distribution
           characteristics about multi-stage atomization field for cutting dust in
           fully mechanized mining face
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Wenjing Yin, Gang Zhou, Danhong Gao To improve the dust suppression efficiency of the external spray systems of shearers, a dust reduction method consisting of shearer external multi-stage atomization and dust removal fan was proposed. Computational fluid dynamics-based numerical simulation was combined with atomization experiments to analyze the migration and distribution of the cutting dust and multi-stage atomization field under airflow at the 2307 fully mechanized mining face of the Tangkou mine. The results show that with adding dust removal fan and multi-stage atomization points, the peak area of wind speed appeared on both sides of the shearer, and the wind speed was greater than 2.7 m/s, the dust concentration on the downside side of the shearer decreased, the spray coverage area increased significantly, and the droplet concentration at the shearer drum was the largest, exceeding 0.05 kg/m3. According to the research results, the multi-stage atomization arrangement of single-fluid water nozzles of shearer was put forward, and the field application was carried out. Compared with the engineering application results of the single-stage atomization dust suppression system, the total dust reduction rate of the synergistic effect of multi-stage atomization external spray with dust removal fan for the shearer is 87.12%, which is 38.59% higher than that of the conventional single-stage atomization dust suppression system.Graphical abstractGraphical abstract for this article
       
  • Research on mine dust suppression by spraying: Development of an
           air-assisted PM10 control device based on CFD technology
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Huitian Peng, Wen Nie, Haiming Yu, Weimin Cheng, Peng Bai, Qiang Liu, Zhiqiang Liu, Shibo Yang, Changwei Xu, Yun Hua, Cheng Guo, Qingxin Ma In order to solve the serious pollution problem of PM10 in a fully mechanized mining face, focusing on the drum cutting process which produces the most dust, a new type of shearer sprayer is developed in the paper. At present, it is difficult for a single spray device to meet the dust control demands of a mine. Therefore, in combination with the airflow-carrying-droplet mechanism, a fan is added to the shearer’s spray device to develop an air-assisted PM10 control device. A No. III nozzle is optimally chosen following the spray experiments, and CFD software is used for a numerical simulation of the 4307 fully mechanized mining face of the Bailu Coal Mine. According to the airflow and spraying field distribution, it is observed that when the spray device’s pressure is 8 MPa, the spraying field’s microscopic parameters are more conducive to the settling of PM10 by the mist droplets. The PM10 data measured at 1#-3# measuring points of the 4307 fully mechanized mining face of the Bailu Coal Mine have shown that the best PM10 settling effect is at a spraying pressure of 8 MPa. The PM10 concentrations at 1#-3# measure points were reduced to 0.987 mg/m3, 0.405 mg/m3 and 0.262 mg/m3 respectively, with the dust control rate being above 90%. Thus the serious PM10 pollution problem in a fully mechanized mining face has been solved effectively.Graphical abstractThe air-assisted PM10 control device was designed. We optimized the nozzle according to the spraying field’s multi-characteristic experimental platform and verified through a spray experiment – CFD numerical simulation. Then, we obtained the distribution law of spraying field and the best spray parameters of the air-assisted PM10 control device by CFD simulation. The test was carried out on the 4307 fully mechanized mining face, and the dust concentration was measured and analyzed.Graphical abstract for this article
       
  • Polymeric micropowders from thermal reversible crosslinking of oligomers
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Hansol Nam, Won-Ji Lee, Sang-Ho Cha, Kyung Jin Lee Polymeric microparticles provide great potentials for applications originated from their high surface area and functionalities and thus have attained many attentions in various fields. Here, we attempt to fabricate polymeric micropowders based on the reversible thermal crosslinking (Diels-Alder reaction). Initially, poly(FEEMA) obtained from the radical polymerization of furan functionalized monomer and partially crosslinked poly(FEEMA) respectively. The physical properties of base-polymer for fabrication of microparticles have changed in order to control thermal responsible property of final micro particles. Based on Diels-Alder reaction, microparticles in the size range of 200 nm–2 μm were successfully prepared using polymer precursors and cross-linker in oil-in-water emulsion. Controlling the molecular weight as well as crosslinked density of polymer precursors makes it possible to adjust the thermal properties (glass transition temperature and retro-Diels-Alder temperature) of the microparticles. These series of method can provide thermal triggered, selective meltdown microparticles for several application fields such as selective gluing, patching, filling or healing by applying external heat.Graphical abstractPolymeric micropowders cross-linked by thermally reversible cross-linker were prepared from well-designed furan containing polymer precursors and via step-polymerization using bismaleimide as a crosslinker in oil-in-water emulsion. The thermal properties of microparticles (glass transition temperature, retro-Diels-Alder temperature) can be readily controlled by adjusting properties of polymeric precursors.Graphical abstract for this article
       
  • Synthesis and characterization of tantalum carbide nanoparticles using
           concentrated solar energy
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Yannely Carvajal-Campos, Laura Ceballos-Mendivil, Francisco Baldenebro-López, Carlos Pérez-Rábago, Claudio A. Estrada Tantalum carbide (TaC) nanoparticles were synthesized using the IER-UNAM (HoSIER) solar furnace, which reduces polluting gas emissions and dependence on fossil fuels through the use of concentrated solar energy. TaC synthesis was performed through a carbothermal reduction method from Ta/O/C complex, using tantalum pentachloride (TaCl5) and synthesized phenolic resin as sources of tantalum and carbon, respectively, at a temperature of 1200 °C, in a reaction time of 30 min, under argon atmosphere. A solar reactor equipped with a quartz window was used, designed to work in controlled atmospheres. Complex Ta/O/C bonds and thermal decomposition were analyzed by FT-IR and TG/DSC, respectively, while the structure and morphology of TaC were analyzed by XRD, TEM, and SEM techniques. Results showed a TaC with a cubic crystalline structure, a low amount of Ta2O5 and a near-spherical morphology. According to Debye-Scherrer, the average crystallite size was 21 nm.Graphical abstractGraphical abstract for this article
       
  • Effect of level of overflow solid outlet on pressure drop of a bubbling
           fluidized-bed
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Daewook Kim, Gyoung Woo Lee, Yoo Sube Won, Jeong-Hoo Choi, Ji Bong Joo, Ho-Jung Ryu, Sung-Ho Jo The effect of level of the overflow outlet for continuous flow of solid particles on the pressure drop of a bubbling fluidized-bed that employed an in-bed inlet for solid feed was investigated with changing solid properties, solid feed rate, gas velocity, and level of the overflow outlet. The pressure drop of fluidized-bed (Δpbed,f) decreased with increasing gas velocity, but increased with either solid feed rate or level of the overflow solid outlet (L). The Δpbed,f/L increased with L. Irrespective of particle size and density, bed height converted for minimum fluidization condition (pressure head by bed weight, Hmf,f) decreased with increasing the volume flow rate of bubble but increased with either the solid feed rate or the level of the overflow solid outlet. The nominal vertical height, height between the Hmf,f and the level of the overflow outlet, that bubbles transported particles while drawing the solid particles out of the fluidized-bed increased as either the volume flow rate of bubble or level of the overflow outlet increased. However, it decreased as the solid feed rate increased. It appeared that the power of bubble for lifting solid to be discharged through the overflow outlet was same at the fixed volume flow rate of bubble, solid feed rate, and level of the overflow solid exit. The power of bubble increased with the level of the overflow outlet but not linearly. The correlation proposed for the pressure drop across the bubbling fluidized-bed was useful to predict the pressure drop across the recycle chamber of the loop seal and the external solid circulation rate in the circulating fluidized-bed system.Graphical abstractEffects of solid feed rate and level of overflow solid outlet on pressure drop of bubbling fluidized-bed.Graphical abstract for this article
       
  • Effect of temperature-related factors on densification, microstructure and
           mechanical properties of powder metallurgy TiAl-based alloys
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Dongjun Wang, Honggang Zhao, Wei Zheng In the present work, the influence of temperature-related factors, including sintering temperature, heating step and temperature-control mode, on the densification, microstructure and mechanical properties of Ti-46.5Al-2.15Cr-1.90Nb-(B, Y, Mo) alloys prepared by SPS has been investigated and discussed in detail. The results obviously indicate that the sintering temperature plays a key role on densification and phase transition, when compared with the heating step and temperature-control mode. Based on the experimental results and theoretical analysis, the densification process and microstructural evolution of TiAl-based alloys during sintering are studied. Moreover, the mechanical properties of the sintered alloys are determined by the combined effects of the densification and microstructure. The obtained results will help to optimize the microstructure and properties for this kind of intermetallic alloys through controlling sintering parameters during powder metallurgy process.Graphical abstractGraphical abstract for this article
       
  • Ball-milling properties and sintering behavior of
           Fe-Tm2O3 mixture powders
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Yongshuai Mu, Guang Ran, Weisong Wu, Chao Ye Aimed at the existing problems of current neutron absorbers that were used in control rods to safely operate a nuclear reactor, new type of Fe-based Tm2O3 composites and Fe-based TmFeO3 composites, which were synthesized from the Fe-25.68 wt.%Tm2O3 mixture powders by ball milling, cold isostatic pressing and sintering, were designed as next generation neutron absorbers in the present work. During ball milling, Tm2O3 was fined, nano-crystallized, amorphized and then dissolved into Fe crystal lattice to form Fe (Tm, O) nanocrystalline solid solution. The effect of sintering temperature and oxygen content at sintering environment on the phases of the sintered bulks were researched, and the corresponding mechanism was discussed. Nanoscale TmFeO3 and Tm2O3 particles were distributed in the sintered bulk matrix. The microhardness, compression strength, and the coefficients of thermal expansion of the bulks sintered at different conditions were measured and discussed. The coefficient of linear expansion and compressive strength increased with increasing ball-milling time. The microhardness increased with increasing sintering temperature when the temperature was lower than 1200 °C. Meanwhile, the microhardness and compressive strength of Fe-based Tm2O3 composites were larger than that of Fe-based TmFeO3 composites, opposite for the coefficients of thermal expansion.Graphical abstractGraphical abstract for this article
       
  • Optimization of aqueous microgrinding processes for fibrous plant
           materials
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Frederik Flach, Lennart Fries, Jana Kammerhofer, Jutta Hesselbach, Benedikt Finke, Carsten Schilde, Gerhard Niederreiter, Stefan Palzer, Stefan Heinrich, Arno Kwade Fibrous plant-based materials are characterized by inhomogeneous structure and composition, which further evolve during wet grinding processes and affect the surface functionality of micronized particles. Therefore, the performance of aqueous microgrinding operations in stirred media mills can be optimized by investigating the interaction between process conditions and material properties of heterogeneous fibrous plant materials.In this experimental study it is shown how particle size reduction, tendency of re-agglomeration and stability of the suspension of micronized particles are driven by the specific energy input, residence time, temperature and presence of surfactants during the milling process. A structured experimental approach is described to optimize the achievable particle size reduction, expressed by the top cut diameter d90,3. It was found that the applied wet milling process determines the stability of particle suspensions throughout further downstream processing, making the grinding process the core unit operation with respect to the performance and formulation of food products containing micronized particles.Graphical abstractGraphical abstract for this article
       
  • The effect of ball milling on properties of sintered manganese-doped
           alumina
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): S. Filipović, N. Obradović, S. Marković, M. Mitrić, I. Balać, A. Đorđević, V. Pavlović Alumina-based compounds have many technological applications and attract great attention even after decades of investigation, due to their good chemical, electrical, and mechanical properties. A mixture of several alumina modifications (α-, κ-, γ-Al2O3) doped with 1 wt% of Mn2O3 was used for this experiment. The powder was mechanically activated for 60 min in an ethanol medium. After compaction, green bodies were sintered in the temperature range from 1200 to 1400 °C. Microstructures of the obtained specimens were investigated by scanning electron microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDS). The influence of morphological changes on electrical and mechanical properties was examined in detail. We have developed a test fixture and corresponding software for measurement of the relative dielectric permittivity and the loss tangent of ceramic specimens. This new method overcomes the problems of dimensions and shape of samples, as well as the problem of applying silver paste. The accuracy is around 2% for ε'r and 0.003 for tanδ. We demonstrate that the mechanical activation (MA) has the dominant influence on lowering the characteristic temperatures and microstructure development, which further leads to increased permittivity and tensile strength.Graphical abstractInfluence of mechanical activation, in wet media, on relative dielectric permeability was measured using new method of collecting and processing of data.Graphical abstract for this article
       
  • CO2 pretreatment and hydrothermal treatment of commercial γ-Al2O3 powders
           for purification and refinement
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Min Gao, Ping Zhao, Benxue Liu, Xibin Yi, Yue Xu Ultrapure, nanosized alumina (Al2O3) powders are highly required for high performance Al2O3 ceramics. However, the synthesis of the powders via an efficient and low-cost way is still a challenge. In the present research, we treated commercial γ-Al2O3 powders via hydrothermal treatment combined with CO2 pretreatment technique. The effect of hydrothermal pressure on the crystal phase, particle size and purity of the treated powders were investigated. In addition, the effect of CO2 pretreatment on the purification of the powders was discussed. Commercial γ-Al2O3 powders are fully converted to boehmite (AlOOH, a derived form of Al2O3) at a hydrothermal pressure of 3.5 MPa. The boehmite powders reduce to the minimum particle size of 50–100 nm after being hydrothermal treated at 3.5 MPa. CO2 pretreatment has been found to be very efficient in the purification of the powders. The Al2O3 content of the powders after being CO2 pretreated at 1 MPa could reach up to 99.9410% which is much larger than that of commercial γ-Al2O3 powders (99.5096%). The as-received ultrapure, nanosized boehmite powders are promised raw materials for high performance Al2O3 ceramics.Graphical abstractGraphical abstract for this article
       
  • Analysis of grinding kinetics in a laboratory ball mill using
           population-balance-model and discrete-element-method
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Hansol Lee, Kwanho Kim, Hoon Lee Grinding processing consumes a lot of energy in mineral processing, but it is a low-efficiency process in which only approximately 1% of the total energy is used to reduce the actual particle size. Therefore, an efficient operation in the grinding process increases the competitiveness of the production and is an essential for enhancing the energy efficiency of the entire mineral processing procedure.Therefore, the study will focus on to finding a different method to predicting the particle size distribution of the ball mill, by using the PBM which reflects the actual size distributions of ground product and the DEM which can understand the internal particle behavior in the mill chamber. First, the grinding parameters were calculated by applying size distributions of ground product under various conditions to PBM and the behaviors of the particles inside the ball mill obtained through DEM were analyzed to predict the distribution of the impact energy used for grinding. Next, the relational expression between the grinding rate parameter and the normal force applied to the grinding materials was derived. Using the relational expression derived from this study, it was confirmed that the size distributions in other conditions can be predicted.Graphical abstractGraphical abstract for this article
       
  • CFD analysis of employing a novel ecofriendly nanofluid in a miniature pin
           fin heat sink for cooling of electronic components: Effect of different
           configurations
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Mehdi Bahiraei, Saeed Heshmatian, Marjan Goodarzi, Hossein Moayedi This research aims to study the thermal and hydraulic attributes as well as energy efficiency of a new ecofriendly nanofluid including functionalized graphene nanoplatelets in a mini heat sink with three different pin fins. The circular, triangular and drop-shaped pin fins are investigated and compared with each other. The effects of nanoparticle fraction and flow velocity on the thermal resistance, temperature uniformity, convective heat transfer coefficient, maximum surface temperature, average surface temperature, pressure loss and pumping power are assessed. Increasing the concentration or velocity reduces the temperature on the heated wall, and also improves the temperature distribution uniformity. At both constant velocity and invariant pumping power, the heat sink fitted with the circular pin fins leads to the best performance while that equipped with the triangular pin fins results in the worst efficiency. In addition, the Figure of Merit (FoM) is greater than 1 for all conditions, which proves that the nanoparticle suspension possesses a greater merit to be employed as the coolant in the heat sinks compared to the base fluid.Graphical abstractGraphical abstract for this article
       
  • A contact model for the deformation behaviour of pharmaceutical pellets
           under cyclic loading
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Dominik Weis, Fabian Krull, Julia Mathy, Maria Evers, Markus Thommes, Sergiy Antonyuk Spherical pharmaceutical pellets are commonly produced by an extrusion-spheronization process. In the spheronizer, the wet cylindrical extrudates are rounded into spheres due to multiple collisions. In order to model this rounding, a suitable contact model, which can predict the dominantly plastic deformation behaviour, is necessary. In this study, a novel cyclic model for wet and dry pellets was developed. Various single particle compression and impact tests with pellets produced from microcrystalline cellulose (MCC) and lactose were conducted to calibrate and validate this model. It was found that the model is able to predict the energy dissipation as well as the deformation during pellet impact in the velocity range which is relevant for the spheronization process. Since the pellets are loaded multiple times during this process, the model was designed in order to account for the increasing flattening and hardening in the contact area as a function of the number of loading cycles. Therefore, the presented model allows the description of the pellet deformation by repeated stressing.Graphical abstractGraphical abstract for this article
       
  • Hydrothermal processing on potassic syenite powder: Zeolite synthesis and
           potassium release kinetics
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Changjiang Liu, Hongwen Ma, Yuan Gao To make potassium accessible to agricultural application from K-silicates, processing on potassic syenite powder under mild alkaline hydrothermal conditions was conducted, as a result of which, potassium became accessible into solution, and to two zeolite powders (analcime and hydroxycancrinite) were successfully obtained. A scale-up operation in 25L-hydrothermal reactor supported the feasibility of further industrial implementation. The kinetic model derived from geochemical study was adopted to describe K+ release behavior, and two kinetic factors, reaction order and apparent activation energy, over temperature range of 477–531 K were 2.61 and 46.61 kJ/mol. The concentrated alkaline solution giving rise to higher reaction order and lower apparent activation energy was a dominated factor accelerating K-feldspar dissolution accomplished within hours. The hydrothermal approach proposed in this work is a simplified and green chemical way for the comprehensive utilization of K-silicates.Graphical abstractGraphical abstract for this article
       
  • Microstructure and properties of Cu-Cr-Nb alloy powder prepared by argon
           gas atomization
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Xueqian Lv, Zuming Liu, Ting Lei, Quan Li, Fan Zhao, Kai Peng, Yake Ren, Sizhe Lu, Bizhong Nong The Cu-2Cr-1Nb (at%) alloy powder was prepared by close-coupled argon gas atomization. The morphology, microstructure and phase were characterized by SEM, TEM, HRTEM, SAED and XRD. The effects of heat treatment on the microstructure and microhardness of the powder were investigated. The alloy matrix had equiaxed crystal structure, and the second phase was Cr2Nb intermetallic compound in sub-micron and nano-scale. Compared with large powder, the second phase of small powder is finer, and its distribution in the matrix is more uniform, the microhardness of the small powder is higher. After heat treatment at 773 K for 1 h, Cr and Nb precipitated and formed a large number of small precipitates, age hardening and peak aging phenomena occurred, and the peak hardness of the powder reached 130 HV. With the increase of heat treatment temperature, the second phase was coarsened. When the heat treatment temperature was 973 K, the short-time heat treatment hardening and long-time heat treatment softening were shown. However, after the heat treatment at 1223 K, only softening phenomenon was observed. This method can be used to prepare the excellent powder for Cu-Cr-Nb alloy, which can be used as a potential structural material for aerospace.Graphical abstractThe second phase in the alloy powder prepared by close coupled argon atomization was submicron and nanometer scale, and distributed in the copper matrix uniformly. The strengthening effect could be increased evidently.Graphical abstract for this article
       
  • Comprehensive numerical modelling of the hot isostatic pressing of
           Ti-6Al-4V powder: From filling to consolidation
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s): Alessandro Abena, Miren Aristizabal, Khamis Essa Hot Isostatic Pressing (HIP) is a manufacturing process for production of near-net-shape components, where models based on Finite Element Method (FEM) are generally used for reducing the expensive experimental trials for canister design. Researches up to date implement in the simulation a uniform powder relative density distribution prior HIPping. However, it has been experimentally observed that the powder distribution is inhomogeneous after filling, leading to a non-uniform tool shrinkage. In this study a comprehensive numerical model for HIPping of Ti-6Al-4V powder is developed to improve model prediction by simulating powder filling and pre-consolidation by means of a two-dimensional Discrete Element Method (DEM). Particles’ dimension has been scaled up in order to reduce the computational cost of the analysis. An analytical model has been developed to calculate the relative density distribution from powder particle distribution provided by DEM, which is then passed in information to a three-dimensional FEM implementing the Abouaf and co-workers model for simulating powder densification during HIPping. Results obtained implementing the initial relative density distribution calculated from DEM are compared with those obtained considering a uniform relative density distribution over the powder domain (classic approach) at the beginning of the analysis. Experimental work has been carried out for validating the DEM (filling) and FEM (HIP) model. Comparison between experimental and numerical results shows the ability of the DEM model to represent the powder flow during filling and pre-consolidation, providing also a reliable values of the relative density distribution. It also highlights that taking into account the non-uniform powder distribution inside the canister prior HIP is vital to improve numerical results and produce near-net-shape components.Graphical abstractGraphical abstract for this article
       
  • Full title (Editorial Board Members)
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s):
       
  • Inside Front Cover (Aims & Scope, Editors)
    • Abstract: Publication date: November 2019Source: Advanced Powder Technology, Volume 30, Issue 11Author(s):
       
  • Enhanced ferromagnetic and photocatalytic properties in Mn or Fe doped
           p-CuO/n-ZnO nanocomposites
    • Abstract: Publication date: Available online 7 September 2019Source: Advanced Powder TechnologyAuthor(s): S.M. Yakout, A.M. El-Sayed Mn doped CuO/ZnO heterostructure exhibited significant room temperature ferromagnetism and visible light photocatalytic properties. Phase analysis for the pure, Mn and Fe doped CuO/ZnO nanocomposites evidently confirmed the formation of CuO and ZnO phases in each composite without any impurities. Based on Rietveld refinement analysis, the inclusion of Mn ions into CuO/ZnO nanocomposite decreased the unit cell volume of both oxides while Fe ions lead to lattice expansion. Mn ions induced the formation of ZnO hexagonal nanorods in CuO/ZnO nanocomposite. Nano-flakes and spherical nanoparticles shapes were seen for Fe doped CuO/ZnO nanocomposites. The characteristics IR absorption bands of CuO and ZnO overlapped together in their nanocomposites structure. From Kubelka-Munk plots, the incorporation of Mn ions enabled the ZnO band gap to absorb in the visible light region. Pure CuO/ZnO nanocomposite exhibited room temperature ferromagnetism with saturation magnetization (Ms) of 0.042 emu/g and coercivity (Hc) of 547 Oe. The ferromagnetic properties of the pure CuO/ZnO nanocomposite were greatly improved by Mn and Fe doping and the saturation magnetization extremely jumped to 0.86 and 0.85 emu/g, respectively. High photocatalytic activity, 98%, with good reusability for methyl orange (MO) degradation under visible light irradiation was achieved by 4 wt% Mn doped CuO/ZnO nanocomposite. A relation between the crystallinity, band gap and photocatalytic activity with dopant type (Mn or Fe) incorporated into CuO/ZnO nanocomposites was noticed. In contrary to Fe dopant, Mn as dopant played successful roles in improving the crystallinity, band gap and photocatalytic properties of CuO/ZnO nanocomposite. Multifunctional properties can be realized by combining different oxides in heterostructure form and using doping technique.Graphical abstractGraphical abstract for this article
       
  • Scalable classification of nanoparticles: A proof of principle for process
           design
    • Abstract: Publication date: Available online 7 September 2019Source: Advanced Powder TechnologyAuthor(s): Christina Menter, Doris Segets Nanoparticles like quantum confined ZnS semiconductor nanocrystals, exhibit unique structure-property relationships. Narrow particle size distributions (PSDs) become one of the most important factors to tailor product performance. Size selective precipitation has already been proven to be an effective post processing strategy for ZnS nanoparticles. It is based on the titration of a poor liquid into a stable dispersion, which leads to the preferred flocculation of larger particles. Afterwards, these flocks must be separated from the continuous phase. While on lab scale the formed flocks can be easily separated by centrifugation from the fine fraction, for larger scale production using continuous processes, new concepts are urgently needed. Herein we developed a filtration process for flock removal that allows the handling of larger quantities. For process design, we first investigated the flock properties in order to know how stable the generated flocks are and how the flock properties can be controlled. Then, we replaced the classical flock separation by centrifugation through separation by surface filtration under the constraint that the underlying separation efficiency was not affected. By the future use of properly controlled, alternating filtration modules, our work opens the door for establishing an urgently needed, scalable post-processing for sub-10 nm nanoparticles.Graphical abstractGraphical abstract for this article
       
  • Estimation of uncertainty of percentile values in particle size
           distribution analysis as a function of number of particles
    • Abstract: Publication date: Available online 6 September 2019Source: Advanced Powder TechnologyAuthor(s): Tatsushi Matsuyama In the analysis of particle size distribution (PSD), evaluation of the uncertainty of the percentile values is often required. Both theoretical and data processing methods are applicable to estimate standard deviations of percentile values. In this paper, a theory, applicable both in paramedic and non-parametric ways, is introduced. As a practical example, theoretical results based on a lognormal distribution are compared to those obtained by bootstrap method. Excellent agreement is demonstrated between the theory and the direct data processing method.Graphical abstractGraphical abstract for this article
       
  • Characterization and photocatalytic activity of Y-doped BiFeO3 ceramics
           prepared by solid-state reaction method
    • Abstract: Publication date: Available online 6 September 2019Source: Advanced Powder TechnologyAuthor(s): Hamed Maleki Singe phase bismuth ferrite doped by yttrium (Bi1−xYxFeO3, x = 0, 0.05, 0.1, 0.15, 0.2 and 0.25) was synthesized by solid-state reaction followed by sintering. Their structural, morphological, ferroelectric, magnetic and optical properties were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), vibrating sample magnetometer (VSM) and UV–visible spectrophotometry. Rhombohedally-distorted perovskite structure of bismuth ferrite was confirmed by XRD analysis and Rietveld refinement. Microstrain and crystallite size were analyzed using Williamson-Hall model. SEM micrographs showed agglomerated particles. The doping of yttrium into the BiFeO3 (BFO) lattice enhanced the ferroelectric and magnetic properties and the leakage current density was reduced. The energy band gap was also decreased by increasing yttrium content, leading to an enhancement of light absorption capability. The photocatalytic activity of all samples has been evaluated by the decolorization of methyl orange (MO) under visible light irradiation. The results indicated that increasing the concentration of yttrium into the BiFeO3 (BFO) structure improved the photodegradation up to 71%.Graphical abstractGraphical abstract for this article
       
  • Dry powder formulation combining bedaquiline with pyrazinamide for latent
           and drug-resistant tuberculosis
    • Abstract: Publication date: Available online 4 September 2019Source: Advanced Powder TechnologyAuthor(s): Mohammad A.M. Momin, Bhamini Rangnekar, Ian Larson, Shubhra Sinha, Shyamal C. Das The purpose of this study was to develop an inhalable combination dry powder formulation of bedaquiline and pyrazinamide and study their physicochemical properties and safety since this combination acts synergistically against Mycobacterium tuberculosis while pyrazinamide alone is active against latent TB and bedaquiline alone is active against drug-resistant TB. The cospray-dried powder of bedaquiline and pyrazinamide with 20% w/w of L-leucine consisted of spherical, porous particles of inhalable size with a diameter ≤3.2 µm. The aerosolization efficiency of the combination powder (FPF:>66%) evaluated using a next generation impactor was higher than bedaquiline-only (FPF: 31.3%) and pyrazinamide-only (FPF: 5.1%) powders, which could be due to the differences in the morphology of the powders. The combination powder was stable during storage for one month in a desiccator and 75% RH and also safe to both Calu-3 and A549 cells up to 100 µg/ml. This is the first report on the development of an inhalable combination dry powder formulation of bedaquiline and pyrazinamide with high aerosolization efficiency. This formulation has the potential to improve the treatment of both latent and drug-resistant TB.Graphical abstractGraphical abstract for this article
       
  • Effect of Re on microstructural evolution and densification kinetics
           during spark plasma sintering of nanocrystalline W
    • Abstract: Publication date: Available online 3 September 2019Source: Advanced Powder TechnologyAuthor(s): Sudipta Pramanik, Ajeet K. Srivastav, Bobu Manuel Jolly, Niraj Chawake, B.S. Murty In the present investigation, nanocrystalline W and W-xRe (x = 3, 5 wt.%) alloy powders were produced by mechanical milling/alloying using high energy ball milling. The nanocrystalline nature (∼50 nm) of these powders was validated by the Rietveld refinement of their respective X-Ray diffraction patterns. Subsequently, spark plasma sintering of the ball milled powders was carried out. It was observed that pure W was not able to densify completely (relative density of 93%) at a temperature of 1500 °C. However, the addition of 5 wt.% Re resulted in near complete densification (relative density of 97%) at the same sintering temperature. The enhanced densification of W-Re powders is mainly attributed to the ductilising effect of Re assisted by the nanocrystallinity of powders, and the application of pressure during sintering.Graphical abstractGraphical abstract for this article
       
  • Effect of Y(NO3)3 additive on morphologies and size of metallic W
           particles produced by hydrogen reduction
    • Abstract: Publication date: Available online 3 September 2019Source: Advanced Powder TechnologyAuthor(s): Zepeng Lv, Dong Liu, Yijie Wu, Run Zhang, Haibo Sun, Jie Dang, Liwen Hu Tungsten, one of the refractory metals, has lots of excellent properties, making tungsten powders become a choice of raw material for many applications. This work reported a simple method (the salt-assisted hydrogen reduction of WO3 powders) for preparing tungsten powders with desired morphologies and size. By adjusting the amount of additive (Y(NO3)3) and reduction temperature, metallic tungsten particles with different morphologies and size were obtained. It was found that both temperature and additive had apparent effects on the morphology and size of metallic W particles, and the large parallelepiped-shaped powders disappeared and large irregular blocky-shaped powders were degraded under the influence of additive. With the increase of temperature and amount of salt, particles became more dispersed and the size increased at higher temperatures, and the shape of particles was changed from spherical to polyhedral as well. On the contrary, the size of sub-particles became smaller as increasing amount of Y(NO3)3 at lower temperatures. Based on the results, the reaction and refining mechanisms for preparing tungsten were proposed as well.Graphical abstractGraphical abstract for this article
       
  • Al 2 O 3 - Cu /water+hybrid+nanoliquid:+Model+prediction+and+stability+analysis&rft.title=Advanced+Powder+Technology&rft.issn=0921-8831&rft.date=&rft.volume=">Critical values in transport phenomena for curved power-law sheet
           utilizing Al 2 O 3 - Cu /water hybrid nanoliquid: Model
           prediction and stability analysis
    • Abstract: Publication date: Available online 3 September 2019Source: Advanced Powder TechnologyAuthor(s): Sanjay Kumar, Pramod Kumar Sharma, Puneet Rana The present investigation reveals the impact of mixture of nanoparticles (Al2O3 and Cu) in basefluid and convective heating on the power-law shrinking curved surface with radius of curvature (K). The homogeneous hybrid nanoliquid (0.1% of Al2O3-Cu/water) model with theoretical and fitted (predicted) experimental correlations is transformed into coupled system of non-linear ordinary differential equations for finding possible branches of solution. The critical values (cc,βc and χc) have been evaluated for some cases, beyond these values there is either no solution or multiple solutions exist. Two different nanofluid models (Model I and II) are compared and found to be contradictory for skin friction and Nusselt number in current physical model. Linear stability analysis for finding stable branch, is also performed through construction of eigenvalue (EV) problem. The MATLAB built-in package LinearFit.model is used for multiple regression estimation (MRE) in case of stable branch which shows that nanoparticle concentration has maximum contribution towards the heat transfer. Moreover, the wall skin friction has strong dependence on curvature parameter. As Prandtl number increases, the linearly fitted model is found to be more suitable for convective boundary case (γ = 0.5).Graphical abstractGraphical abstract for this article
       
 
 
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