Subjects -> ENGINEERING (Total: 2844 journals)
    - CHEMICAL ENGINEERING (259 journals)
    - CIVIL ENGINEERING (255 journals)
    - ELECTRICAL ENGINEERING (182 journals)
    - ENGINEERING (1420 journals)
    - ENGINEERING MECHANICS AND MATERIALS (454 journals)
    - HYDRAULIC ENGINEERING (60 journals)
    - INDUSTRIAL ENGINEERING (101 journals)
    - MECHANICAL ENGINEERING (113 journals)

ENGINEERING (1420 journals)                  1 2 3 4 5 6 7 8 | Last

Showing 1 - 200 of 1205 Journals sorted alphabetically
3 Biotech     Open Access   (Followers: 9)
3D Research     Hybrid Journal   (Followers: 22)
AAPG Bulletin     Hybrid Journal   (Followers: 11)
Abstract and Applied Analysis     Open Access   (Followers: 4)
Aceh International Journal of Science and Technology     Open Access   (Followers: 9)
ACS Nano     Hybrid Journal   (Followers: 448)
Acta Geotechnica     Hybrid Journal   (Followers: 7)
Acta Metallurgica Sinica (English Letters)     Hybrid Journal   (Followers: 10)
Acta Nova     Open Access   (Followers: 1)
Acta Polytechnica : Journal of Advanced Engineering     Open Access   (Followers: 4)
Acta Scientiarum. Technology     Open Access   (Followers: 3)
Acta Universitatis Cibiniensis. Technical Series     Open Access   (Followers: 1)
Active and Passive Electronic Components     Open Access   (Followers: 8)
Adaptive Behavior     Hybrid Journal   (Followers: 9)
Adsorption     Hybrid Journal   (Followers: 5)
Advanced Energy and Sustainability Research     Open Access   (Followers: 7)
Advanced Engineering Forum     Full-text available via subscription   (Followers: 14)
Advanced Engineering Research     Open Access  
Advanced Journal of Graduate Research     Open Access   (Followers: 4)
Advanced Quantum Technologies     Hybrid Journal   (Followers: 1)
Advanced Science     Open Access   (Followers: 13)
Advanced Science Focus     Free   (Followers: 7)
Advanced Science Letters     Full-text available via subscription   (Followers: 13)
Advanced Science, Engineering and Medicine     Partially Free   (Followers: 11)
Advanced Synthesis & Catalysis     Hybrid Journal   (Followers: 20)
Advanced Theory and Simulations     Hybrid Journal   (Followers: 5)
Advances in Catalysis     Full-text available via subscription   (Followers: 8)
Advances in Complex Systems     Hybrid Journal   (Followers: 12)
Advances in Engineering Software     Hybrid Journal   (Followers: 31)
Advances in Fuel Cells     Full-text available via subscription   (Followers: 20)
Advances in Fuzzy Systems     Open Access   (Followers: 5)
Advances in Geosciences (ADGEO)     Open Access   (Followers: 22)
Advances in Heat Transfer     Full-text available via subscription   (Followers: 30)
Advances in Human Factors/Ergonomics     Full-text available via subscription   (Followers: 27)
Advances in Magnetic and Optical Resonance     Full-text available via subscription   (Followers: 10)
Advances in Natural Sciences : Nanoscience and Nanotechnology     Open Access   (Followers: 36)
Advances in Operations Research     Open Access   (Followers: 14)
Advances in OptoElectronics     Open Access   (Followers: 6)
Advances in Physics Theories and Applications     Open Access   (Followers: 21)
Advances in Polymer Science     Hybrid Journal   (Followers: 53)
Advances in Porous Media     Full-text available via subscription   (Followers: 6)
Advances in Remote Sensing     Open Access   (Followers: 58)
Advances in Science and Research (ASR)     Open Access   (Followers: 8)
Aerobiologia     Hybrid Journal   (Followers: 4)
Aerospace Systems     Hybrid Journal   (Followers: 10)
African Journal of Science, Technology, Innovation and Development     Hybrid Journal   (Followers: 8)
AIChE Journal     Hybrid Journal   (Followers: 38)
Ain Shams Engineering Journal     Open Access   (Followers: 7)
Al-Nahrain Journal for Engineering Sciences     Open Access  
Al-Qadisiya Journal for Engineering Sciences     Open Access   (Followers: 2)
AL-Rafdain Engineering Journal     Open Access   (Followers: 3)
Alexandria Engineering Journal     Open Access   (Followers: 3)
AMB Express     Open Access   (Followers: 1)
American Journal of Applied Sciences     Open Access   (Followers: 27)
American Journal of Engineering and Applied Sciences     Open Access   (Followers: 12)
American Journal of Engineering Education     Open Access   (Followers: 20)
American Journal of Environmental Engineering     Open Access   (Followers: 16)
American Journal of Industrial and Business Management     Open Access   (Followers: 31)
Annals of Civil and Environmental Engineering     Open Access   (Followers: 3)
Annals of Combinatorics     Hybrid Journal   (Followers: 3)
Annals of Pure and Applied Logic     Open Access   (Followers: 6)
Annals of Regional Science     Hybrid Journal   (Followers: 10)
Annals of Science     Hybrid Journal   (Followers: 10)
Annual Journal of Technical University of Varna     Open Access   (Followers: 1)
Antarctic Science     Hybrid Journal   (Followers: 1)
Applicable Algebra in Engineering, Communication and Computing     Hybrid Journal   (Followers: 3)
Applicable Analysis: An International Journal     Hybrid Journal   (Followers: 2)
Applications in Energy and Combustion Science     Open Access   (Followers: 2)
Applications in Engineering Science     Open Access   (Followers: 1)
Applied Catalysis A: General     Hybrid Journal   (Followers: 8)
Applied Catalysis B: Environmental     Hybrid Journal   (Followers: 22)
Applied Clay Science     Hybrid Journal   (Followers: 6)
Applied Computational Intelligence and Soft Computing     Open Access   (Followers: 16)
Applied Engineering Letters     Open Access   (Followers: 4)
Applied Magnetic Resonance     Hybrid Journal   (Followers: 4)
Applied Nanoscience     Open Access   (Followers: 11)
Applied Network Science     Open Access   (Followers: 3)
Applied Numerical Mathematics     Hybrid Journal   (Followers: 6)
Applied Physics Research     Open Access   (Followers: 7)
Applied Sciences     Open Access   (Followers: 6)
Applied Spatial Analysis and Policy     Hybrid Journal   (Followers: 6)
Arab Journal of Basic and Applied Sciences     Open Access  
Arabian Journal for Science and Engineering     Hybrid Journal   (Followers: 5)
Archives of Computational Methods in Engineering     Hybrid Journal   (Followers: 6)
Archives of Thermodynamics     Open Access   (Followers: 13)
Arctic     Open Access   (Followers: 7)
Arid Zone Journal of Engineering, Technology and Environment     Open Access   (Followers: 2)
Arkiv för Matematik     Hybrid Journal   (Followers: 1)
ArtefaCToS : Revista de estudios sobre la ciencia y la tecnología     Open Access   (Followers: 1)
Asia-Pacific Journal of Science and Technology     Open Access  
Asian Engineering Review     Open Access  
Asian Journal of Applied Science and Engineering     Open Access   (Followers: 2)
Asian Journal of Applied Sciences     Open Access   (Followers: 2)
Asian Journal of Biotechnology     Open Access   (Followers: 9)
Asian Journal of Control     Hybrid Journal  
Asian Journal of Technology Innovation     Hybrid Journal   (Followers: 7)
Assembly Automation     Hybrid Journal   (Followers: 2)
ATZagenda     Hybrid Journal  
ATZextra worldwide     Hybrid Journal  
AURUM : Mühendislik Sistemleri ve Mimarlık Dergisi = Aurum Journal of Engineering Systems and Architecture     Open Access   (Followers: 1)
Australasian Journal of Engineering Education     Hybrid Journal   (Followers: 3)
Australasian Physical & Engineering Sciences in Medicine     Hybrid Journal   (Followers: 1)
Australian Journal of Multi-Disciplinary Engineering     Hybrid Journal   (Followers: 2)
Autocracy : Jurnal Otomasi, Kendali, dan Aplikasi Industri     Open Access  
Automotive and Engine Technology     Hybrid Journal  
Automotive Experiences     Open Access  
Automotive Innovation     Hybrid Journal   (Followers: 1)
Avances en Ciencias e Ingenierías     Open Access  
Avances: Investigación en Ingeniería     Open Access   (Followers: 6)
Balkan Region Conference on Engineering and Business Education     Open Access   (Followers: 2)
Bangladesh Journal of Scientific and Industrial Research     Open Access  
Basin Research     Hybrid Journal   (Followers: 6)
Batteries     Open Access   (Followers: 11)
Batteries & Supercaps     Hybrid Journal   (Followers: 7)
Bautechnik     Hybrid Journal   (Followers: 3)
Bell Labs Technical Journal     Hybrid Journal   (Followers: 29)
Beni-Suef University Journal of Basic and Applied Sciences     Open Access   (Followers: 3)
Beyond : Undergraduate Research Journal     Open Access  
Bhakti Persada : Jurnal Aplikasi IPTEKS     Open Access  
Bharatiya Vaigyanik evam Audyogik Anusandhan Patrika (BVAAP)     Open Access   (Followers: 1)
Bilge International Journal of Science and Technology Research     Open Access   (Followers: 1)
Biointerphases     Open Access   (Followers: 1)
Biomaterials Science     Full-text available via subscription   (Followers: 14)
Biomedical Engineering     Hybrid Journal   (Followers: 15)
Biomedical Engineering and Computational Biology     Open Access   (Followers: 13)
Biomedical Engineering Letters     Hybrid Journal   (Followers: 5)
Biomedical Engineering: Applications, Basis and Communications     Hybrid Journal   (Followers: 5)
Biomedical Microdevices     Hybrid Journal   (Followers: 8)
Biomedical Science and Engineering     Open Access   (Followers: 7)
Biomicrofluidics     Open Access   (Followers: 7)
Biotechnology Progress     Hybrid Journal   (Followers: 44)
Black Sea Journal of Engineering and Science     Open Access  
Botswana Journal of Technology     Full-text available via subscription   (Followers: 1)
Boundary Value Problems     Open Access   (Followers: 1)
Brazilian Journal of Science and Technology     Open Access   (Followers: 2)
Bulletin of Canadian Petroleum Geology     Full-text available via subscription   (Followers: 13)
Bulletin of Engineering Geology and the Environment     Hybrid Journal   (Followers: 15)
Bulletin of the Crimean Astrophysical Observatory     Hybrid Journal  
Cahiers Droit, Sciences & Technologies     Open Access   (Followers: 1)
Calphad     Hybrid Journal   (Followers: 2)
Canadian Geotechnical Journal     Hybrid Journal   (Followers: 30)
Canadian Journal of Remote Sensing     Full-text available via subscription   (Followers: 50)
Carbon Resources Conversion     Open Access   (Followers: 3)
Carpathian Journal of Electronic and Computer Engineering     Open Access  
Case Studies in Engineering Failure Analysis     Open Access   (Followers: 6)
Case Studies in Thermal Engineering     Open Access   (Followers: 8)
Catalysis Communications     Hybrid Journal   (Followers: 7)
Catalysis Letters     Hybrid Journal   (Followers: 3)
Catalysis Reviews: Science and Engineering     Hybrid Journal   (Followers: 9)
Catalysis Science and Technology     Hybrid Journal   (Followers: 13)
Catalysis Surveys from Asia     Hybrid Journal   (Followers: 4)
Catalysis Today     Hybrid Journal   (Followers: 8)
CEAS Space Journal     Hybrid Journal   (Followers: 6)
Cell Reports Physical Science     Open Access  
Cellular and Molecular Neurobiology     Hybrid Journal   (Followers: 2)
Central European Journal of Engineering     Hybrid Journal  
Chaos : An Interdisciplinary Journal of Nonlinear Science     Hybrid Journal   (Followers: 3)
Chaos, Solitons & Fractals     Hybrid Journal   (Followers: 3)
Chaos, Solitons & Fractals : X     Open Access   (Followers: 1)
Chinese Journal of Catalysis     Full-text available via subscription   (Followers: 3)
Chinese Journal of Engineering     Open Access   (Followers: 2)
Chinese Journal of Population, Resources and Environment     Open Access  
Chinese Science Bulletin     Open Access   (Followers: 1)
Ciencia e Ingenieria Neogranadina     Open Access  
Ciencia en su PC     Open Access   (Followers: 1)
Ciencia y Tecnología     Open Access  
Ciencias Holguin     Open Access   (Followers: 2)
CienciaUAT     Open Access   (Followers: 1)
Cientifica     Open Access  
CIRP Annals - Manufacturing Technology     Hybrid Journal   (Followers: 11)
CIRP Journal of Manufacturing Science and Technology     Hybrid Journal   (Followers: 14)
City, Culture and Society     Hybrid Journal   (Followers: 27)
Clay Minerals     Hybrid Journal   (Followers: 9)
Coal Science and Technology     Full-text available via subscription   (Followers: 4)
Coastal Engineering     Hybrid Journal   (Followers: 14)
Coastal Engineering Journal     Hybrid Journal   (Followers: 9)
Coastal Engineering Proceedings : Proceedings of the International Conference on Coastal Engineering     Open Access   (Followers: 2)
Coastal Management     Hybrid Journal   (Followers: 30)
Coatings     Open Access   (Followers: 4)
Cogent Engineering     Open Access   (Followers: 3)
Cognitive Computation     Hybrid Journal   (Followers: 3)
Color Research & Application     Hybrid Journal   (Followers: 4)
COMBINATORICA     Hybrid Journal  
Combustion Theory and Modelling     Hybrid Journal   (Followers: 17)
Combustion, Explosion, and Shock Waves     Hybrid Journal   (Followers: 20)
Communications Faculty of Sciences University of Ankara Series A2-A3 Physical Sciences and Engineering     Open Access  
Communications in Numerical Methods in Engineering     Hybrid Journal   (Followers: 2)
Components, Packaging and Manufacturing Technology, IEEE Transactions on     Hybrid Journal   (Followers: 28)
Composite Interfaces     Hybrid Journal   (Followers: 10)
Composite Structures     Hybrid Journal   (Followers: 334)
Composites Part A : Applied Science and Manufacturing     Hybrid Journal   (Followers: 276)
Composites Part B : Engineering     Hybrid Journal   (Followers: 311)
Composites Part C : Open Access     Open Access   (Followers: 3)
Composites Science and Technology     Hybrid Journal   (Followers: 245)
Comptes Rendus : Mécanique     Open Access   (Followers: 2)
Computation     Open Access   (Followers: 1)
Computational Geosciences     Hybrid Journal   (Followers: 20)
Computational Optimization and Applications     Hybrid Journal   (Followers: 11)
Computer Applications in Engineering Education     Hybrid Journal   (Followers: 6)
Computer Science and Engineering     Open Access   (Followers: 20)

        1 2 3 4 5 6 7 8 | Last

Similar Journals
Journal Cover
Catalysis Letters
Journal Prestige (SJR): 0.73
Citation Impact (citeScore): 2
Number of Followers: 3  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 1572-879X - ISSN (Online) 1011-372X
Published by Springer-Verlag Homepage  [2658 journals]
  • The Effect of Synthesis Methods on Active Oxygen Species of MnOx-CuO in
           Soot Combustion

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      Abstract: The activity of the catalyst is closely related to the synthesis method. Hereon, we prepared a series of XMn1Cu (X = 2, 4, 6, 8) catalysts by hydrolysis driven redox, co-precipitation and hydrothermal synthesis approaches, respectively. The effect of XMn1Cu synthesized by different strategies on soot combustion activity were compared. The results show that the catalysts fabricated by hydrolysis driven redox have excellent performance than the other two methods in soot removal, and the activity follows r-XMn1Cu > h-XMn1Cu > cop-XMn1Cu. The Mn/Cu = 4:1 is the optimal ratio of Cu-Mn composite oxide. Among the materials, the r-4Mn1Cu sample has the best catalytic activity due to the uniform distribution of Mn and Cu, high specific surface area, enhanced content of Mn4+, promoted concentration of lattice defects and oxygen vacancies, and T10, T50 and T90 are 303, 355 and 386 °C, respectively. The repeated experiments present that r-4Mn1Cu has high activity and stability in soot oxidation. Combined with experimental results and characterization, oxygen vacancies and reactive oxygen generation mechanism of XMn1Cu catalyst in soot combustion were further discussed. Graphic
      PubDate: 2021-11-01
       
  • Enhanced Performance of Palladium Catalyst Confined Within Carbon
           Nanotubes for Heck Reaction

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      Abstract: Confined carbon nanotubes (CNTs) are typically used to tune the activity and stability of catalysts so as to increase their efficiency. Herein, we compared the catalytic performances of palladium nanoparticles (Pd NPs) located in different regions of CNTs for Heck reaction. The catalyst with Pd NPs located in the internal surface of CNTs (Pd-in-CNT) has a higher reaction rate than that with Pd NPs attached on the external surface of CNTs (Pd-out-CNT). The activity of the Pd-in-CNT is 9.4 times higher than that of Pd-out-CNT in the Heck reaction, possibly because of the smaller particle size and modified redox properties of the confined Pd NPs. The CNT cavities create more active sites, consistenting with a higher microcalorimetric adsorption of carbon monoxide. Leaching of the Pd species during the reactions was observed with both types of catalysts. However, the Pd-in-CNT catalyst showed lower leaching than that of Pd-out-CNT owing to the spatial restriction of the channels in the former. More importantly, these novel catalysts were also used to synthesize a broad range of p-substituted iodobenzene derivatives, affording new and efficient route for the synthesis of valuable fine chemicals via carbon–carbon bond cross-coupling reactions. Graphic
      PubDate: 2021-11-01
       
  • Ligand and Base Free Synthesis of Biaryls from Aryl Halides in Aqueous
           Media with Recyclable Ti0.97Pd0.03O1.97 Catalyst

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      Abstract: Facile protocol for the synthesis of biaryls from aryl halides in presence of magnesium metal without prior formation of organometallic intermediate has been exploited. Irrespective of aqueous medium, Ti0.97Pd0.03O1.97 catalyst supports C–C bond formation reaction in presence of metals rather than dehalogenation without any additives. Homocoupling of 16 different aryl halides furnished corresponding biphenyls in good yield with better functional group tolerance. The recovery of the catalyst was carried out by employing catalyst coated cordierite monolith up to 7th cycle with high yields. A new approach for the cross-coupling reaction is also attempted. Graphic
      PubDate: 2021-11-01
       
  • Photo-Chemically-Deposited and Industrial Cu/ZnO/Al2O3 Catalyst Material
           Surface Structures During CO2 Hydrogenation to Methanol: EXAFS, XANES and
           XPS Analyses of Phases After Oxidation, Reduction, and Reaction

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      Abstract: Industrial Cu/ZnO/Al2O3 or novel rate catalysts, prepared with a photochemical deposition method, were studied under functional CH3OH synthesis conditions at the set temperature (T) range of 240–350 °C, 20 bar pressure, and stoichiometric carbon dioxide/hydrogen composition. Analytical scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), X-ray adsorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) methods were systematically utilized to investigate the interfaces, measured local geometry, and chemical state electronics around the structured active sites of commercially available Cu/ZnO/Al2O3 material or synthesized Cu/ZnO. Processed Cu K-edge EXAFS analysis suggested that various Cu atom species, clusters, metallic fcc Cu, Cu oxides (Cu2O or CuO) and the Cu0.7Zn2 alloy with hexagonal crystalline particles are contained after testing. It was proposed that in addition to the model’s Cu surface area, the amount, ratio and dispersion of the mentioned bonded Cu compounds significantly influenced activity. Additionally, XPS revealed that carbon may be deposited on the commercial Cu/ZnO/Al2O3, forming the inactive carbide coating with Cu or/and Zn, which may be the cause of basicity’s severe deactivation during reactions. The selectivity to methanol decreased with increasing T, whereas more Cu0.7Zn2 inhibited the CO formation through reverse water–gas shift (RWGS) CO2 reduction. Graphic
      PubDate: 2021-11-01
       
  • A Facile Route to Prepare PbZr Nanocomposite Catalysts for the Efficient
           Synthesis of Diphenyl Carbonate

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      Abstract: Diphenyl carbonate is a versatile chemical intermediate and key building block for the synthesis of polycarbonates. A facile route to prepare PbZr nanocomposites were developed using different precipitants to investigate the effect on the catalytic activity of the solid acid catalysts. The structure–performance relationship of the nanocomposites, dispersion of active components and structure stability, and the catalytic performance were thoroughly analyzed. The results showed that there existed the interaction between Zr and Pb, which induced the homogenous dispersion of Pb and high surface acid sites that could enhance the catalytic activities. Among the catalysts, PbZr–NH4OH represented the best catalytic performance and superior stability, indicating that NH4OH was more favorable compared with sodium hydroxide, ammonium carbonate and urea. The research provides a valuable reference in a wide range application of nanocomposite preparation for the effective and clean production of various carbonates. Graphic
      PubDate: 2021-11-01
       
  • Improving Biocatalytic Synthesis of Furfuryl Alcohol by Effective
           Conversion of D-Xylose into Furfural with Tin-Loaded Sulfonated Carbon
           Nanotube in Cyclopentylmethyl Ether-Water Media

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      Abstract: Carbon nanotube (CNT) was utilized as as the precursor to synthesize solid acid (tin-loaded sulfonated carbon nanotube, SO42−/SnO2-CNT) for catalyzing D-xylose into furfural. Fourier transform infrared spectroscopy, Roman spectroscopy, X-ray diffraction analysis, and scanning electron microscope techniques were used for characterizing SO42−/SnO2-CNT. Different loading of D-xylose (20–100 g/L) were converted into furfural (81.6–299.1 mM) at 41.9–61.2% yield by SO42−/SnO2-CNT (3.5 wt%) within 15 min at 180 °C in cyclopentylmethyl ether-water (1:2, v:v) biphasic media. Subsequently, whole-cells of recombinant Escherichia coli CG-19 cells expressing reductase catalyzed D-xylose-derived furfural at 35 ℃ and pH 7.5. Within 3 h, the prepared D-xylose (81.6–299.1 mM) could be converted into furfuryl alcohol at 32.7–61.2% yield (based on the D-xylose loading). Sequential conversion of D-xylose with SO42−/SnO2-CNT and reductase catalysts was established for the effective production of furfuryl alcohol. Graphic
      PubDate: 2021-11-01
       
  • Converting Cyclohexanone to Liquid Fuel-Grade Products: A Characterization
           and Comparison Study of Hydrotreating Molybdenum Catalysts

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      Abstract: Developing biomass-based strategies for liquid bio-fuels production is promising for the reduction of the aftereffects of fossil fuels. The conversion of lignin-derived intermediates such as cyclohexanone is currently of a great deal of interest. The current study aims to evaluate the molybdenum-based hydrotreating catalysts for the conversion of cyclohexanone in the presence of hydrogen. Catalytic experiments at 400 °C, 15 bar, and a range of WHSV were developed. The experiments reveal that catalyst type and reaction WHSV affect the cyclohexanone conversion, product distribution, deoxygenation efficiency, total hydrocarbon production capacity, and heating value of the product blend. The main products include C6 cyclic and aromatic hydrocarbons and oxygenates. Cyclohexane, cyclohexene, benzene, cyclohexanol, and phenol are major products. Small quantities of methylcyclopentane and bicyclic hydrocarbons and oxygenates are also reported in some cases. Increasing WHSV reduced the cyclohexanone conversion. Cyclohexanone conversions up to 89% were observed at the lowest WHSVs over a cobalt-molybdenum sample. The highest hydrocarbon production capacity (99.53%) was managed at WHSV = 5.240 gcyclohexanone/gcat h over a cobalt-molybdenum sample, while the highest deoxygenation efficiency, i.e. 81.29% degree of deoxygenation and 5.35 C/O ratio enhancement were achieved at WHSV = 0.262 gcyclohexanone/gcat h by a nickel-molybdenum sample. The heating values would be enhanced by up to 22.7% when cyclohexanone is converted over the utilized catalysts. The larger heating value (44.90 MJ/kg, 22.7% enhancement) was obtained over a nickel-molybdenum catalyst, which is comparable to the energy density of the conventional fuels. The results reveal that the catalysts are efficient in the conversion of cyclohexanone to liquid bio-fuels. Graphic
      PubDate: 2021-11-01
       
  • Adsorption Behavior and Electron Structure Engineering of Pd-IL Catalysts
           for Selective Hydrogenation of Acetylene

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      Abstract: Developing the catalytic activity and selectivity of palladium (Pd) catalysts for acetylene hydrogenation is key importance in the chemical industry and remains a challenge to this day. Here, the catalytic performance of Pd catalysts are influenced by the Pd electronic structure, in turn, controlled by different heteroatom doped support. Different catalysts are prepared by ionic liquids (ILs) with different precursors, and catalytic activity of selective hydrogenation of acetylene was investigated. The Pd/NC catalyst exhibits extraordinary conversion, selectivity and stable for the hydrogenation of acetylene (94.6% acetylene conversion with 91.3% selectivity to ethylene). This remarkable catalytic performance of Pd/NC is mainly linked to nitrogen-doped (N-doped) changes the electronic structure of Pd nanoparticles, ensures the rapid desorption of ethylene and prevents the formation of unnecessary ethane by over hydrogenation (demonstrated by XPS and DFT). Our strategy of controlling the electronic structure of Pd can be widely used in the reactions that change the micro electrochemical properties of active metals. Graphic The selective hydrogenation of acetylene to ethylene over Pd/NC with excellent conversion and selectivity is investigated. The doping of nitrogen leads to the unique electronic structure of Pd on the Pd/NC catalyst, which influences the adsorption of ethylene and acetylene, thus promoting its catalytic activity.
      PubDate: 2021-11-01
       
  • Intensification of Heterogeneous Photocatalytic Reactions Without
           Efficiency Losses: The Importance of Surface Catalysis

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      Abstract: Advances in LED and photoreactor technology have brought semiconductor photocatalysis to the verge of feasibility of industrial application for the synthesis of value-added chemicals. However, the often observed efficiency losses under intensified illumination conditions still present a great challenge. This perspective discusses the origin of these efficiency losses and what needs to be done to prevent or counteract it and pave the way for efficient, intensified heterogeneous photocatalytic processes. The role of surface catalysis is particularly highlighted as one of the rate-limiting steps. Graphic
      PubDate: 2021-11-01
       
  • Pd/Mg(OH)2 Heterogeneous Nanocatalysts Synthesized by a Facile One-Pot
           Hydrothermal Method for CO Direct Esterification to Dimethyl Oxalate

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      Abstract: Pd-based heterogeneous nanocatalysts have wide application in chemical industry. However, the traditional synthesis process contains multi-steps such as impregnation, dry, calcination and reduction. The pre-synthesis nanoparticles process can reduce the steps, but need to remove the surfactants, which are added in the synthesis process. In this work, a facile one-pot hydrothermal synthesis process named as single molecular precursor method was successfully developed to prepare Pd/Mg(OH)2 heterogeneous nanocatalysts with clean surface. The as-synthesized Pd/Mg(OH)2 heterogeneous nanocatalysts show excellent performance for CO direct esterification to dimethyl oxalate (DMO). The WTY (weight time yield) of DMO can reach the high-performance of 2544 g kgcat.−1 h−1, while the conversion of CO is 62.6% and selectivity to DMO is 90.8%. The single molecular precursor method developed by this work can be extended to other supported noble metal nanocatalysts. Graphic
      PubDate: 2021-11-01
       
  • Palladium-PEPPSI-NHC Complexes Bearing Imidazolidin-2-Ylidene Ligand:
           Efficient Precatalysts for the Direct C5-Arylation of
           N-Methylpyrrole-2-Carboxaldehyde

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      Abstract: The Pd-catalyzed direct arylation of pyrroles is an important research field for organic synthesis and catalysis chemistry. However, imidazolidin-2-ylidene based Pd-NHC complexes (NHC=N-heterocyclic carbene) have not yet been employed as catalysts for the direct C5 mono-arylation of C2-substituted N-methylpyrrole derivatives with aryl halides. Therefore, we now report the synthesis and characterization of new 1,3-bis(substituted benzyl) imidazolinium salts as carbene precursors, and their corresponding Pd-PEPPSI-NHC type complexes (PEPPSI=Pyridine Enhanced Precatalyst Preparation Stabilization and Initiation). The catalytic properties of these complexes have been evaluated in the direct C5 mono-arylation of N-methylpyrrole-2-carboxaldehyde with a wide variety of (hetero)aryl halides. This environmentally attractive procedure has also been found to be tolerant to a wide variety of functional groups on the aryl halides such as formyl, acetyl, nitrile, fluoro or trifluoromethyl, and good yields have been obtained in presence of 1 mol% catalyst loading at 120 °C. Graphic
      PubDate: 2021-11-01
       
  • Catalyst Deactivation Rate During Hydrogenation of CO2 to Longer-Chained
           Hydrocarbons Over 6 wt% Potassium-Promoted Co/Al2O3 Catalyst

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      Abstract: The deactivation rate of 15%Co-6%K/Al2O3 Fischer–Tropsch catalyst during hydrogenation of CO2 to longer-chained hydrocarbons was investigated. The catalysts used were synthesized by incipient wetness impregnation of gamma alumina- support and characterized by TPR, BET, XPS, and XRD. The presence of CO2 in the feed displayed a negative impact on the catalyst stability and in the production of longer-chain hydrocarbons. The main product generated was methane; this was due to the presence of the cobalt carbide which led to decreased C5+ selectivity with a concomitant increase of CH4 formation. As the TOS was increasing, carbonaceous deposits formed on the catalyst. These deposits tend to lean towards methane formation, decrease CO2 conversion, and C5+ selectivity as observed in this study. Cobalt carbide formation in the spent catalyst in this study can account, at least in part, for the observed catalyst deactivation with time on stream. Graphic
      PubDate: 2021-11-01
       
  • Characterization and Performance of Ca-Substituted La1−xCaxCoO3−δ
           Perovskite for Efficient Catalytic Oxidation of Toluene

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      Abstract: Perovskite oxides with ABO3 structure are promising heterogeneous catalysts. This work intends to modify the physicochemical properties and catalytic behaviors of perovskite-type oxides by A-site substitution. La1−xCaxCoO3−δ perovskite catalysts with various x = 0, 0.1, 0.3, 0.5 and 0.7 were prepared and the toluene oxidation performance was investigated. The results show that the calcium substitution increased the surface area, pore volume of the perovskite oxides and the crystal structure was transformed from rhombohedral to cubic symmetry after calcium substitution. Besides, it also changed the surface element composition, low-temperature reducibility and surface oxygen species amounts. 50% of calcium substitution in A-site (La0.5Ca0.5CoO3−δ) was thought to be the optimal content due to the best comprehensive physicochemical properties. The toluene oxidation test verified that the La0.5Ca0.5CoO3−δ presented the best catalytic performance with T50% = 183 °C and T90% = 218 °C. The catalytic process was related closely with the rapid transformation of Co2+/Co3+ and the consumption and regeneration of surface adsorbed oxygen. A mechanism of toluene oxidation over La1−xCaxCoO3−δ perovskite was proposed. Graphic
      PubDate: 2021-11-01
       
  • Statistical Product Selectivity Modeling and Optimization for
           γ-Al2O3-Supported Cobalt Catalysts-Based Fischer–Tropsch Synthesis

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      Abstract: The statistical selectivity models were developed for four different Fischer–Tropsch synthesis product range, including methane (CH4), light olefins (C2=C4), light paraffins (C2–C4), and long-chain hydrocarbons (C5+), based on the experimental data obtained over thirteen γ-Al2O3 supported cobalt-based catalysts with different cobalt particle and pore sizes. The input variables consist of cobalt metal particle size and catalyst pore size. The cubic and quadratic polynomial equations were fitted to the experimental data, however, the mathematical models were subjected to model reduction for the enhancement of model adequacy, which was investigated through ANOVA. The multi-objective optimization revealed that the maximum C5+ selectivity (84.150%) could be achieved at the cobalt particle size and pore sizes of 14.764 and 23.129 nm, respectively, while keeping the selectivity to other hydrocarbon products minimum. Graphic
      PubDate: 2021-11-01
       
  • Effect of Tourmaline Addition on the Catalytic Performance and SO2
           Resistance of NixMn3−xO4 Catalyst for NH3-SCR Reaction at Low
           Temperature

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      Abstract: NixMn3−xO4 and NixMn3−xO4/T (T represents tourmaline) catalysts with a double-layer hollow structure were prepared by a rigid template method for low-temperature selective catalytic reduction of NOx with NH3 (NH3-SCR). The catalytic activity and SO2 tolerance performance of NixMn3−xO4 catalyst were enhanced by the addition of 2 wt% tourmaline. The results showed the addition of tourmaline could affect the growth, shell thickness and redox property of the NixMn3−xO4 catalysts. The relative contents of Mn4+ and surface chemical oxygen were also increased by the addition of tourmaline, which were beneficial for improving the SCR activity, the catalyst showed 100% NO conversion in a low-temperature range of 125–240 °C. The mechanism of SCR reaction and SO2 tolerance were analyzed by In-situ DRIFTS. The SCR reaction process mostly follows Langmuir–Hinshelwood (L–H) mechanisms. The primary NOx adsorption materials on NixMn3−xO4/T catalyst were nitrate bidentate and bridge nitrate, which was not affected by SO2, and it had excellent SO2 tolerance at 150 ℃. Graphic
      PubDate: 2021-11-01
       
  • C3N Non-metallic Catalyst for Propane Dehydrogenation: A Density
           Functional Theory Study

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      Abstract: In this work, density functional theory is used to study the mechanism of propane dehydrogenation over non-metallic C3N catalyst. The structure, electrostatic potential and density of state of C3N are introduced, as well as the adsorption of reactants on catalyst is studied. The propane dehydrogenation reaction is divided into the first dehydrogenation and the second dehydrogenation (deep dehydrogenation). We explore the possible dehydrogenation pathways in two-step dehydrogenation. The rate control step of the first dehydrogenation is the removal of methylene hydrogen atom from propane, and its energy barrier is 47.79 kcal/mol, which reflected the catalytic activity of the catalyst. The rate control step of deep dehydrogenation is the process of removing the first hydrogen atom of the product propylene to produce the by-product. The energy barrier is 72.80 kcal/mol, which is much larger than that of the first step of dehydrogenation, reflecting the excellent selectivity of the catalyst. Graphic
      PubDate: 2021-11-01
       
  • Enhanced Photoelectrochemical Performance of Hematite Photoanode by
           Decorating NiCoP Nanoparticles Through a Facile Spin Coating Method

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      Abstract: Hematite (α-Fe2O3) is a potential photoanode material for photoelectrochemical (PEC) water splitting, but its short hole diffusion length and low water oxidation kinetics prevent its practical application. In general, the hole transport rate and the water oxidation kinetics could be improved by modifying the oxygen evolution cocatalysts (OECs) in the proper way. In this work, we designed and synthesized a bimetallic phosphides NiCoP nanoparticles (NPs) modified (Ti, Zr)-codoped hematite photoanode (TZ-H) by a facile spin coating method to achieve the uniform and close interface contact of semiconductor/OECs. Under the optimal conditions, the as-prepared photoanode exhibits high and stable PEC performance with a current density of 2.38 mA/cm2 at 1.23 V vs. RHE, which is one of the best performances of noble-metal-free hematite-based photoanodes for water oxidation. Moreover, the surface efficiency of charge separation is improved by NiCoP modification, which is increased from 59% to 91% at 1.23 V vs. RHE and reached nearly 99% at higher potential. This work not only proves that NiCoP NPs are outstanding OECs but also provides a new strategy for the design of noble-metal-free semiconductor/OECs photoanodes with high-quality interface contact. Graphic
      PubDate: 2021-11-01
       
  • Cellulosic CuI Nanoparticles as a Heterogeneous, Recyclable Catalyst for
           the Borylation of α,β-Unsaturated Acceptors in Aqueous Media

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      Abstract: We have demonstrated that cellulosic CuI nanoparticles could perform as an efficient heterogeneous catalyst for the synthesis of useful organoboron compounds. Desired β-borylation products were all obtained in good to excellent yields under mild conditions. This catalyst could be recovered easily and still work effectively in six runs. Notably, asymmetric synthesis of organoboron compounds was accomplished by applying a chiral phosphine ligand. This newly developed protocol provides an efficient and sustainable pathway for the formation of C-B bonds and largely extends the applied range of cellulose. Graphical Asymmetric and efficient synthesis of organoboron compounds was accomplished by cellulosic CuI nanoparticles combining with a chiral phosphine ligand. This newly reported strategy provides a green and sustainable method for the construction of C–B bonds and largely extends the applied range of cellulose.
      PubDate: 2021-11-01
       
  • Synthesis of C21H38ClN Assisted Si Pillared Clays and the Effects of CeO2
           Addition on Its Supported Palladium Catalyst for Benzene Oxidation

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      Abstract: Mesoporous silica-pillared clays (SPC) were prepared with C21H38ClN cationic surfactant as template and supported PdOx catalysts were prepared by impregnation method. The influence of addition of CeO2 on benzene combustion was evaluated. The samples were characterized by N2 adsorption–desorption, XRD, XPS, HRTEM and TPSR. Compared with the raw montmorillonite, the d001 value of SPC increased from 0.96 to 3.45 nm. Furthermore, the surface area was increased from 30 to 835 m2/g and the pore volume was increased from 0.11 to 1.30 cm3/g, respectively. The addition of CeO2 increased oxygen vacancies and improved the dispersion of PdOx on SPC, and the optimal addition of CeO2 was 10%. Therefore, of all the catalysts, 0.3%Pd/10%Ce/SPC could completely oxidize benzene at 280 °C, showing the highest catalytic activity. This catalyst showed high activity for benzene oxidation in wet conditions with or without Cl− displaying good durability, which should be related to the presence of Ce3+ on the surface of catalyst after reaction. The excellent pore structure of SPC, improved dispersion of PdOx and high concentration of Ce3+ on the catalyst surface were the key factors for the high catalytic activity of 0.3%Pd/10%Ce/SPC. Graphic Mesoporous silica-pillared clays (SPC) were synthesized and SPC supported CeO2 and PdO catalysts were prepared by impregnation method. The 0.3% Pd/10% Ce/SPC catalyst displayed the highest activity for benzene combustion.
      PubDate: 2021-11-01
       
  • Evolution Mechanism of N2O for the Selective Catalytic Reduction of NOx by
           NH3 Over Cu-SSZ-13 Assisted Fe-BEA Catalysts

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      Abstract: The effects of N2O formation over Cu-SSZ-13 assisted Fe-BEA (1Cu1Fe-M) catalysts, for the selective catalytic reduction of NOx by NH3, were systematically investigated to elucidate the mechanism of N2O evolution. The experimental results showed that NO2/NOx ratio determined the amount of N2O formation, while zeolite framework topology, O2 concentration, NH3 oxidation and NO oxidation had only a slight effect on N2O formation. For different NO2/NOx feed conditions (0, 0.2, 0.4, 0.5), 1Cu1Fe-M catalysts showed maximum N2O formation and decreases in N2 selectivity at around 230 °C (21 ppm of N2O yield, 94% N2 selectivity) and 570 °C (18 ppm of N2O yield, 95%N2 selectivity). A proposed mechanism shows that NO2 guided the formation of ammonium nitrate species on Lewis acid sites at low temperature, to account for N2O formation at low temperature. Besides this, the addition of NO2 increases the side reactions at high temperature and cause a relative decrease in Bronsted acid sites. Moreover, the decrease in N2O formation over 1Cu1Fe-M catalysts was observed. These results indicated that the FeOx species of 1Cu1Fe-M contribute to N2O decomposition by the addition of Fe-BEA. Graphic
      PubDate: 2021-11-01
       
 
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