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Publisher: Elsevier   (Total: 3043 journals)

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Showing 1 - 200 of 3043 Journals sorted alphabetically
AASRI Procedia     Open Access   (Followers: 15)
Academic Pediatrics     Hybrid Journal   (Followers: 20, SJR: 1.402, h-index: 51)
Academic Radiology     Hybrid Journal   (Followers: 18, SJR: 1.008, h-index: 75)
Accident Analysis & Prevention     Partially Free   (Followers: 83, SJR: 1.109, h-index: 94)
Accounting Forum     Hybrid Journal   (Followers: 23, SJR: 0.612, h-index: 27)
Accounting, Organizations and Society     Hybrid Journal   (Followers: 27, SJR: 2.515, h-index: 90)
Achievements in the Life Sciences     Open Access   (Followers: 4)
Acta Anaesthesiologica Taiwanica     Open Access   (Followers: 5, SJR: 0.338, h-index: 19)
Acta Astronautica     Hybrid Journal   (Followers: 333, SJR: 0.726, h-index: 43)
Acta Automatica Sinica     Full-text available via subscription   (Followers: 3)
Acta Biomaterialia     Hybrid Journal   (Followers: 25, SJR: 2.02, h-index: 104)
Acta Colombiana de Cuidado Intensivo     Full-text available via subscription   (Followers: 1)
Acta de Investigación Psicológica     Open Access   (Followers: 2)
Acta Ecologica Sinica     Open Access   (Followers: 8, SJR: 0.172, h-index: 29)
Acta Haematologica Polonica     Free   (SJR: 0.123, h-index: 8)
Acta Histochemica     Hybrid Journal   (Followers: 3, SJR: 0.604, h-index: 38)
Acta Materialia     Hybrid Journal   (Followers: 225, SJR: 3.683, h-index: 202)
Acta Mathematica Scientia     Full-text available via subscription   (Followers: 5, SJR: 0.615, h-index: 21)
Acta Mechanica Solida Sinica     Full-text available via subscription   (Followers: 9, SJR: 0.442, h-index: 21)
Acta Oecologica     Hybrid Journal   (Followers: 9, SJR: 0.915, h-index: 53)
Acta Otorrinolaringologica (English Edition)     Full-text available via subscription   (Followers: 1)
Acta Otorrinolaringológica Española     Full-text available via subscription   (Followers: 3, SJR: 0.311, h-index: 16)
Acta Pharmaceutica Sinica B     Open Access   (Followers: 2)
Acta Poética     Open Access   (Followers: 4)
Acta Psychologica     Hybrid Journal   (Followers: 23, SJR: 1.365, h-index: 73)
Acta Sociológica     Open Access  
Acta Tropica     Hybrid Journal   (Followers: 6, SJR: 1.059, h-index: 77)
Acta Urológica Portuguesa     Open Access  
Actas Dermo-Sifiliograficas     Full-text available via subscription   (Followers: 4)
Actas Dermo-Sifiliográficas (English Edition)     Full-text available via subscription   (Followers: 3)
Actas Urológicas Españolas     Full-text available via subscription   (Followers: 4, SJR: 0.383, h-index: 19)
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Actualites Pharmaceutiques     Full-text available via subscription   (Followers: 5, SJR: 0.141, h-index: 3)
Actualites Pharmaceutiques Hospitalieres     Full-text available via subscription   (Followers: 4, SJR: 0.112, h-index: 2)
Acupuncture and Related Therapies     Hybrid Journal   (Followers: 3)
Ad Hoc Networks     Hybrid Journal   (Followers: 11, SJR: 0.967, h-index: 57)
Addictive Behaviors     Hybrid Journal   (Followers: 15, SJR: 1.514, h-index: 92)
Addictive Behaviors Reports     Open Access   (Followers: 5)
Additive Manufacturing     Hybrid Journal   (Followers: 8, SJR: 1.039, h-index: 5)
Additives for Polymers     Full-text available via subscription   (Followers: 20)
Advanced Drug Delivery Reviews     Hybrid Journal   (Followers: 134, SJR: 5.2, h-index: 222)
Advanced Engineering Informatics     Hybrid Journal   (Followers: 11, SJR: 1.265, h-index: 53)
Advanced Powder Technology     Hybrid Journal   (Followers: 16, SJR: 0.739, h-index: 33)
Advances in Accounting     Hybrid Journal   (Followers: 9, SJR: 0.299, h-index: 15)
Advances in Agronomy     Full-text available via subscription   (Followers: 15, SJR: 2.071, h-index: 82)
Advances in Anesthesia     Full-text available via subscription   (Followers: 25, SJR: 0.169, h-index: 4)
Advances in Antiviral Drug Design     Full-text available via subscription   (Followers: 3)
Advances in Applied Mathematics     Full-text available via subscription   (Followers: 6, SJR: 1.054, h-index: 35)
Advances in Applied Mechanics     Full-text available via subscription   (Followers: 10, SJR: 0.801, h-index: 26)
Advances in Applied Microbiology     Full-text available via subscription   (Followers: 22, SJR: 1.286, h-index: 49)
Advances In Atomic, Molecular, and Optical Physics     Full-text available via subscription   (Followers: 16, SJR: 3.31, h-index: 42)
Advances in Biological Regulation     Hybrid Journal   (Followers: 4, SJR: 2.277, h-index: 43)
Advances in Botanical Research     Full-text available via subscription   (Followers: 3, SJR: 0.619, h-index: 48)
Advances in Cancer Research     Full-text available via subscription   (Followers: 25, SJR: 2.215, h-index: 78)
Advances in Carbohydrate Chemistry and Biochemistry     Full-text available via subscription   (Followers: 9, SJR: 0.9, h-index: 30)
Advances in Catalysis     Full-text available via subscription   (Followers: 5, SJR: 2.139, h-index: 42)
Advances in Cellular and Molecular Biology of Membranes and Organelles     Full-text available via subscription   (Followers: 12)
Advances in Chemical Engineering     Full-text available via subscription   (Followers: 24, SJR: 0.183, h-index: 23)
Advances in Child Development and Behavior     Full-text available via subscription   (Followers: 10, SJR: 0.665, h-index: 29)
Advances in Chronic Kidney Disease     Full-text available via subscription   (Followers: 10, SJR: 1.268, h-index: 45)
Advances in Clinical Chemistry     Full-text available via subscription   (Followers: 28, SJR: 0.938, h-index: 33)
Advances in Colloid and Interface Science     Full-text available via subscription   (Followers: 18, SJR: 2.314, h-index: 130)
Advances in Computers     Full-text available via subscription   (Followers: 16, SJR: 0.223, h-index: 22)
Advances in Developmental Biology     Full-text available via subscription   (Followers: 11)
Advances in Digestive Medicine     Open Access   (Followers: 4)
Advances in DNA Sequence-Specific Agents     Full-text available via subscription   (Followers: 5)
Advances in Drug Research     Full-text available via subscription   (Followers: 22)
Advances in Ecological Research     Full-text available via subscription   (Followers: 42, SJR: 3.25, h-index: 43)
Advances in Engineering Software     Hybrid Journal   (Followers: 25, SJR: 0.486, h-index: 10)
Advances in Experimental Biology     Full-text available via subscription   (Followers: 7)
Advances in Experimental Social Psychology     Full-text available via subscription   (Followers: 40, SJR: 5.465, h-index: 64)
Advances in Exploration Geophysics     Full-text available via subscription   (Followers: 3)
Advances in Fluorine Science     Full-text available via subscription   (Followers: 8)
Advances in Food and Nutrition Research     Full-text available via subscription   (Followers: 47, SJR: 0.674, h-index: 38)
Advances in Fuel Cells     Full-text available via subscription   (Followers: 15)
Advances in Genetics     Full-text available via subscription   (Followers: 15, SJR: 2.558, h-index: 54)
Advances in Genome Biology     Full-text available via subscription   (Followers: 11)
Advances in Geophysics     Full-text available via subscription   (Followers: 6, SJR: 2.325, h-index: 20)
Advances in Heat Transfer     Full-text available via subscription   (Followers: 21, SJR: 0.906, h-index: 24)
Advances in Heterocyclic Chemistry     Full-text available via subscription   (Followers: 8, SJR: 0.497, h-index: 31)
Advances in Human Factors/Ergonomics     Full-text available via subscription   (Followers: 26)
Advances in Imaging and Electron Physics     Full-text available via subscription   (Followers: 2, SJR: 0.396, h-index: 27)
Advances in Immunology     Full-text available via subscription   (Followers: 35, SJR: 4.152, h-index: 85)
Advances in Inorganic Chemistry     Full-text available via subscription   (Followers: 9, SJR: 1.132, h-index: 42)
Advances in Insect Physiology     Full-text available via subscription   (Followers: 3, SJR: 1.274, h-index: 27)
Advances in Integrative Medicine     Hybrid Journal   (Followers: 5)
Advances in Intl. Accounting     Full-text available via subscription   (Followers: 4)
Advances in Life Course Research     Hybrid Journal   (Followers: 8, SJR: 0.764, h-index: 15)
Advances in Lipobiology     Full-text available via subscription   (Followers: 2)
Advances in Magnetic and Optical Resonance     Full-text available via subscription   (Followers: 9)
Advances in Marine Biology     Full-text available via subscription   (Followers: 16, SJR: 1.645, h-index: 45)
Advances in Mathematics     Full-text available via subscription   (Followers: 10, SJR: 3.261, h-index: 65)
Advances in Medical Sciences     Hybrid Journal   (Followers: 6, SJR: 0.489, h-index: 25)
Advances in Medicinal Chemistry     Full-text available via subscription   (Followers: 5)
Advances in Microbial Physiology     Full-text available via subscription   (Followers: 4, SJR: 1.44, h-index: 51)
Advances in Molecular and Cell Biology     Full-text available via subscription   (Followers: 22)
Advances in Molecular and Cellular Endocrinology     Full-text available via subscription   (Followers: 10)
Advances in Molecular Toxicology     Full-text available via subscription   (Followers: 7, SJR: 0.324, h-index: 8)
Advances in Nanoporous Materials     Full-text available via subscription   (Followers: 4)
Advances in Oncobiology     Full-text available via subscription   (Followers: 3)
Advances in Organometallic Chemistry     Full-text available via subscription   (Followers: 15, SJR: 2.885, h-index: 45)
Advances in Parallel Computing     Full-text available via subscription   (Followers: 7, SJR: 0.148, h-index: 11)
Advances in Parasitology     Full-text available via subscription   (Followers: 7, SJR: 2.37, h-index: 73)
Advances in Pediatrics     Full-text available via subscription   (Followers: 24, SJR: 0.4, h-index: 28)
Advances in Pharmaceutical Sciences     Full-text available via subscription   (Followers: 13)
Advances in Pharmacology     Full-text available via subscription   (Followers: 15, SJR: 1.718, h-index: 58)
Advances in Physical Organic Chemistry     Full-text available via subscription   (Followers: 7, SJR: 0.384, h-index: 26)
Advances in Phytomedicine     Full-text available via subscription  
Advances in Planar Lipid Bilayers and Liposomes     Full-text available via subscription   (Followers: 3, SJR: 0.248, h-index: 11)
Advances in Plant Biochemistry and Molecular Biology     Full-text available via subscription   (Followers: 8)
Advances in Plant Pathology     Full-text available via subscription   (Followers: 5)
Advances in Porous Media     Full-text available via subscription   (Followers: 4)
Advances in Protein Chemistry     Full-text available via subscription   (Followers: 18)
Advances in Protein Chemistry and Structural Biology     Full-text available via subscription   (Followers: 19, SJR: 1.5, h-index: 62)
Advances in Psychology     Full-text available via subscription   (Followers: 60)
Advances in Quantum Chemistry     Full-text available via subscription   (Followers: 5, SJR: 0.478, h-index: 32)
Advances in Radiation Oncology     Open Access  
Advances in Small Animal Medicine and Surgery     Hybrid Journal   (Followers: 2, SJR: 0.1, h-index: 2)
Advances in Space Research     Full-text available via subscription   (Followers: 345, SJR: 0.606, h-index: 65)
Advances in Structural Biology     Full-text available via subscription   (Followers: 8)
Advances in Surgery     Full-text available via subscription   (Followers: 7, SJR: 0.823, h-index: 27)
Advances in the Study of Behavior     Full-text available via subscription   (Followers: 30, SJR: 1.321, h-index: 56)
Advances in Veterinary Medicine     Full-text available via subscription   (Followers: 16)
Advances in Veterinary Science and Comparative Medicine     Full-text available via subscription   (Followers: 13)
Advances in Virus Research     Full-text available via subscription   (Followers: 5, SJR: 1.878, h-index: 68)
Advances in Water Resources     Hybrid Journal   (Followers: 43, SJR: 2.408, h-index: 94)
Aeolian Research     Hybrid Journal   (Followers: 5, SJR: 0.973, h-index: 22)
Aerospace Science and Technology     Hybrid Journal   (Followers: 310, SJR: 0.816, h-index: 49)
AEU - Intl. J. of Electronics and Communications     Hybrid Journal   (Followers: 8, SJR: 0.318, h-index: 36)
African J. of Emergency Medicine     Open Access   (Followers: 5, SJR: 0.344, h-index: 6)
Ageing Research Reviews     Hybrid Journal   (Followers: 8, SJR: 3.289, h-index: 78)
Aggression and Violent Behavior     Hybrid Journal   (Followers: 408, SJR: 1.385, h-index: 72)
Agri Gene     Hybrid Journal  
Agricultural and Forest Meteorology     Hybrid Journal   (Followers: 15, SJR: 2.18, h-index: 116)
Agricultural Systems     Hybrid Journal   (Followers: 30, SJR: 1.275, h-index: 74)
Agricultural Water Management     Hybrid Journal   (Followers: 38, SJR: 1.546, h-index: 79)
Agriculture and Agricultural Science Procedia     Open Access  
Agriculture and Natural Resources     Open Access   (Followers: 1)
Agriculture, Ecosystems & Environment     Hybrid Journal   (Followers: 53, SJR: 1.879, h-index: 120)
Ain Shams Engineering J.     Open Access   (Followers: 5, SJR: 0.434, h-index: 14)
Air Medical J.     Hybrid Journal   (Followers: 5, SJR: 0.234, h-index: 18)
AKCE Intl. J. of Graphs and Combinatorics     Open Access   (SJR: 0.285, h-index: 3)
Alcohol     Hybrid Journal   (Followers: 9, SJR: 0.922, h-index: 66)
Alcoholism and Drug Addiction     Open Access   (Followers: 6)
Alergologia Polska : Polish J. of Allergology     Full-text available via subscription   (Followers: 1)
Alexandria Engineering J.     Open Access   (Followers: 1, SJR: 0.436, h-index: 12)
Alexandria J. of Medicine     Open Access  
Algal Research     Partially Free   (Followers: 8, SJR: 2.05, h-index: 20)
Alkaloids: Chemical and Biological Perspectives     Full-text available via subscription   (Followers: 3)
Allergologia et Immunopathologia     Full-text available via subscription   (Followers: 1, SJR: 0.46, h-index: 29)
Allergology Intl.     Open Access   (Followers: 4, SJR: 0.776, h-index: 35)
ALTER - European J. of Disability Research / Revue Européenne de Recherche sur le Handicap     Full-text available via subscription   (Followers: 7, SJR: 0.158, h-index: 9)
Alzheimer's & Dementia     Hybrid Journal   (Followers: 48, SJR: 4.289, h-index: 64)
Alzheimer's & Dementia: Diagnosis, Assessment & Disease Monitoring     Open Access   (Followers: 5)
Alzheimer's & Dementia: Translational Research & Clinical Interventions     Open Access   (Followers: 3)
American Heart J.     Hybrid Journal   (Followers: 48, SJR: 3.157, h-index: 153)
American J. of Cardiology     Hybrid Journal   (Followers: 45, SJR: 2.063, h-index: 186)
American J. of Emergency Medicine     Hybrid Journal   (Followers: 38, SJR: 0.574, h-index: 65)
American J. of Geriatric Pharmacotherapy     Full-text available via subscription   (Followers: 6, SJR: 1.091, h-index: 45)
American J. of Geriatric Psychiatry     Hybrid Journal   (Followers: 16, SJR: 1.653, h-index: 93)
American J. of Human Genetics     Hybrid Journal   (Followers: 31, SJR: 8.769, h-index: 256)
American J. of Infection Control     Hybrid Journal   (Followers: 24, SJR: 1.259, h-index: 81)
American J. of Kidney Diseases     Hybrid Journal   (Followers: 33, SJR: 2.313, h-index: 172)
American J. of Medicine     Hybrid Journal   (Followers: 46, SJR: 2.023, h-index: 189)
American J. of Medicine Supplements     Full-text available via subscription   (Followers: 3)
American J. of Obstetrics and Gynecology     Hybrid Journal   (Followers: 187, SJR: 2.255, h-index: 171)
American J. of Ophthalmology     Hybrid Journal   (Followers: 54, SJR: 2.803, h-index: 148)
American J. of Ophthalmology Case Reports     Open Access   (Followers: 3)
American J. of Orthodontics and Dentofacial Orthopedics     Full-text available via subscription   (Followers: 6, SJR: 1.249, h-index: 88)
American J. of Otolaryngology     Hybrid Journal   (Followers: 23, SJR: 0.59, h-index: 45)
American J. of Pathology     Hybrid Journal   (Followers: 26, SJR: 2.653, h-index: 228)
American J. of Preventive Medicine     Hybrid Journal   (Followers: 21, SJR: 2.764, h-index: 154)
American J. of Surgery     Hybrid Journal   (Followers: 34, SJR: 1.286, h-index: 125)
American J. of the Medical Sciences     Hybrid Journal   (Followers: 12, SJR: 0.653, h-index: 70)
Ampersand : An Intl. J. of General and Applied Linguistics     Open Access   (Followers: 5)
Anaerobe     Hybrid Journal   (Followers: 4, SJR: 1.066, h-index: 51)
Anaesthesia & Intensive Care Medicine     Full-text available via subscription   (Followers: 55, SJR: 0.124, h-index: 9)
Anaesthesia Critical Care & Pain Medicine     Full-text available via subscription   (Followers: 9)
Anales de Cirugia Vascular     Full-text available via subscription  
Anales de Pediatría     Full-text available via subscription   (Followers: 2, SJR: 0.209, h-index: 27)
Anales de Pediatría (English Edition)     Full-text available via subscription  
Anales de Pediatría Continuada     Full-text available via subscription   (SJR: 0.104, h-index: 3)
Analytic Methods in Accident Research     Hybrid Journal   (Followers: 2, SJR: 2.577, h-index: 7)
Analytica Chimica Acta     Hybrid Journal   (Followers: 38, SJR: 1.548, h-index: 152)
Analytical Biochemistry     Hybrid Journal   (Followers: 164, SJR: 0.725, h-index: 154)
Analytical Chemistry Research     Open Access   (Followers: 8, SJR: 0.18, h-index: 2)
Analytical Spectroscopy Library     Full-text available via subscription   (Followers: 11)
Anesthésie & Réanimation     Full-text available via subscription   (Followers: 1)
Anesthesiology Clinics     Full-text available via subscription   (Followers: 22, SJR: 0.421, h-index: 40)
Angiología     Full-text available via subscription   (SJR: 0.124, h-index: 9)
Angiologia e Cirurgia Vascular     Open Access  
Animal Behaviour     Hybrid Journal   (Followers: 158, SJR: 1.907, h-index: 126)
Animal Feed Science and Technology     Hybrid Journal   (Followers: 5, SJR: 1.151, h-index: 83)
Animal Reproduction Science     Hybrid Journal   (Followers: 5, SJR: 0.711, h-index: 78)
Annales d'Endocrinologie     Full-text available via subscription   (Followers: 1, SJR: 0.394, h-index: 30)
Annales d'Urologie     Full-text available via subscription  
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Annales de Chirurgie de la Main et du Membre Supérieur     Full-text available via subscription  
Annales de Chirurgie Plastique Esthétique     Full-text available via subscription   (Followers: 2, SJR: 0.354, h-index: 22)
Annales de Chirurgie Vasculaire     Full-text available via subscription   (Followers: 1)

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Journal Cover Advances in Fluorine Science
  [8 followers]  Follow
    
   Full-text available via subscription Subscription journal
   ISSN (Print) 1872-0358
   Published by Elsevier Homepage  [3043 journals]
  • Chapter 1 Fluoride Removal from Water Using Adsorption Technique
    • Abstract: 2006
      Publication year: 2006
      Source:Advances in Fluorine Science, Volume 2

      Management of contaminants such as fluoride is a major public issue. Fluoride of geogenic origin in groundwater used as a source of drinking water is a major concern because fluoride content above permissible levels is responsible for human dental and skeletal fluorosis. Consequently, water sources containing elevated levels of fluoride have to be treated. Coagulation/precipitation, electrochemical, electrodialysis, reverse osmosis, adsorption and hybrid processes combining adsorption and dialysis are widely used defluoridation techniques. Currently, however, the development of cost effective and clean processes due to economic constraints and stringent environmental policies is desired. Adsorption technique is arguably one of the most versatile of all the defluoridation techniques due to a number of reasons such as cost, diverse end-uses, socio-cultural acceptance, regulatory compliance, environmental benignity and simplicity. For this technique, activated alumina, bone char and clay adsorption media are the most developed. During the past two decades, extensive research has focused on a number of alternative adsorbents, some exhibiting improved fluoride sorption performances while at the same time do not alter the quality of treated water. Studies have also shifted toward systematic modeling to approximate adsorber design parameters. In view of these, this review opens with a description of paradigm shifts in drinking water sources and highlights the genesis and toxicological effects of fluoride in drinking water as a means of defining the existing problem. Next, potential and established techniques for defluoridation are revisited. This is closely followed with a review of defluoridation adsorbents recognized by the World Health Organization and those novel defluoridation adsorbents reported in literature over the last two decades, with special reference to drinking water. Emphasis is laid on their availability, fluoride sorption capacity and mechanisms. In recognizing surface-tailored zeolite as a novel sorbent, detailed analysis of fluoride adsorption behavior is provided for this sorbent. Finally, defluoridation adsorption unit configurations, and challenges to and prospects for their implementation are briefly discussed.

      PubDate: 2012-12-15T09:29:36Z
       
  • Chapter 2 Water Defluoridation Processes: A Review. Application:
           Nanofiltration (NF) for Future Large-Scale Pilot Plants
    • Abstract: 2006
      Publication year: 2006
      Source:Advances in Fluorine Science, Volume 2

      Defluoridation of waters using clays as substrates has become popular in many countries to solve problems related to high fluoride concentrations in drinking water in rural areas. But this treatment is limited to low fresh water production. In this work, F− elimination using a nanofiltration (NF) operation will solve problems for-large-scale pilot plants in the future. Results obtained in these fields help-users to facilitate the selection between reverse osmosis (RO) and NF membranes of the most cost-effective membrane for desalination of high fluorinated water. Two sorts of characterization have been developed: (i) physico-chemicals, in terms of hydrophobicity/hydrophilicity, morphology and topography aspects and (ii) mass transfer in terms of pure water and saline solution permeabilities, charged solute rejections and molecular weight cut-off (MWCO). A model inspired by the phenomenological approach proposed by Kedem and Katchalsky (KK) will help to quantify both parts of the mass transfer occurring in NF and RO, i.e. the pure convection and the pure diffusion, separately. This new and original approach will be applied to three membranes, 2 NF and 1 LPRO (low-polarization reverse osmosis), respectively. The study will be limited to low concentration polarization by using diluted solutions (10−3–10−1 M) and high tangential flow rate (4ms−1) under low conversion ratio (5%), operational conditions. Different tools such as contact angle measurements, topography and roughness measurements using atomic force microscopy (AFM), hydraulic permeability and salt solution permeability, will be used to characterize the three membranes. This analytical approach will be coupled with the Spiegler, Kedem and Katchalsky (SKK) phenomenological mass transfer model in order to determine the mass transfer parameters σ and P s for synthetic chloride and sulphate solutions. This novel integer approach makes it possible to determine today an NF most efficient membrane for the elimination of excess F− in a Senegalese water sample taken from the endemic region of Fatick. This membrane denoted NF90 works very well due to its diffusional behaviour for fluoride rejection, its high hydraulic permeability and sufficient observed rejection for F− in comparison to RO.

      PubDate: 2012-12-15T09:29:36Z
       
  • Chapter 3 Calixpyrrole–Fluoride Interactions: From Fundamental Research
           to Applications in the Environmental Field
    • Abstract: 2006
      Publication year: 2006
      Source:Advances in Fluorine Science, Volume 2

      Synthetic macrocycles such as calixpyrroles are capable of complexing anions and discriminating between them most effectively. This chapter is concerned with calixpyrrole and derivatives with selective properties towards the fluoride anion as demonstrated through the use of spectrometric, electrochemical and thermal (calorimetry) data. Selectivity is one of the main features in supramolecular chemistry. As such the importance of thermodynamics in assessing quantitatively selectivity is emphasised. An account is given about the steps undertaken for the thermodynamic characterisation of the binding process involving calixpyrroles and the fluoride anion in different media. Thus based on stability constant data, selectivity factors are calculated to illustrate the anion, receptor and medium effects on the selective binding of calixpyroles with the fluoride anion. Representative examples are given to demonstrate the role of solvation on the complexation process. The applications of calixpyrroles in the design of sensors and new materials with potential use as decontaminant agents for the removal of fluorides from water are discussed.

      PubDate: 2012-12-15T09:29:36Z
       
  • Chapter 4 Fluorine-Containing Agrochemicals: An Overview of Recent
           Developments
    • Abstract: 2006
      Publication year: 2006
      Source:Advances in Fluorine Science, Volume 2

      The dramatic effect of fluorine on the biological activity of agrochemicals such as herbicides, insecticides, fungicides, and plant growth regulators has earned fluorine a unique place in the toolbox of the agrochemical chemist. Introduction of fluorine into a biologically active molecule during the structure–activity optimization process can dramatically modify its biological activity by affecting any of a number of parameters, such as binding to a target receptor or enzyme, transporting the bioactive molecule from the point of application to the target site, and blocking metabolic deactivation. This enhanced role of fluorine in the discovery of new agrochemicals is reflected in more than three-fold increase in the number of fluorine-containing agrochemicals in the past three decades. In this review, we discuss recent developments and challenges in the field of fluorine-containing agrochemicals and place them in the context of work done in the past five decades.

      PubDate: 2012-12-15T09:29:36Z
       
  • Chapter 5 Fluorine: Friend or Foe' A Green Chemist's Perspective
    • Abstract: 2006
      Publication year: 2006
      Source:Advances in Fluorine Science, Volume 2

      The contribution of fluorine chemistry to the field of clean chemical technology is reviewed. The roles of fluorochemicals in the environment and the ways in which they may be involved in inherently ‘greener’ processes are discussed.

      PubDate: 2012-12-15T09:29:36Z
       
  • Chapter 6 Emerging “Greener” Synthetic Routes to Hydrofluorocarbons:
           Metal Fluoride-Mediated Oxyfluorination
    • Abstract: 2006
      Publication year: 2006
      Source:Advances in Fluorine Science, Volume 2

      Current technologies used in the manufacture of aliphatic and aromatic hydrofluorocarbons (HCFs) generate large quantities of waste, particularly hydrochloric acid, which is under severe environmental scrutiny and needs to be eliminated. Although highly desirable, direct and selective conversion of a C–H bond to a C–F bond using HF is not feasible due to the thermodynamic considerations. An environmentally “greener” process for the synthesis of fluorocarbons can be envisioned through an intermediate inorganic metal fluoride that is capable of fluorinating a C–H bond of a desirable hydrocarbon and could be regenerated to the appropriate oxidized metal fluoride with oxygen and HF. This process, when successfully implemented, will eliminate H2O as the only by-product. In this chapter, we review on our research efforts to achieve oxyfluorination of a C–H bond to C–F bond using HF recyclable inorganic metal fluorides (e.g. CuF2, AgF) to form many industrially important aliphatic and aromatic hydrofluorocarbons used in the manufacture of refrigerants, etching agents, industrial polymers, pharmaceuticals and agrochemicals.

      PubDate: 2012-12-15T09:29:36Z
       
  • Chapter 7 Fluorine Analysis by Ion Beam Techniques for Dating Applications
    • Abstract: 2006
      Publication year: 2006
      Source:Advances in Fluorine Science, Volume 2

      Megaelectron volt (MeV) ion beam techniques offer a number of non-destructive analysis methods that allow to measure depth profiles of elemental concentrations in material surfaces. Elements are identified by elastic scattering, by specific nuclear reaction products or by emission of characteristic X-rays. With nuclear microprobes raster images of the material composition at the surface can be obtained. Particle-induced gamma-ray emission (PIGE) is especially suited for fluorine detection down to the ppm concentration level. The technical aspects of fluorine detection by nuclear reactions as well as its applications to fluorine analysis in geological and archaeological objects are reviewed. Special attention is given to the determination of exposure ages of meteorites on the Antarctic ice shield and burial durations of archaeological bones and teeth. This information can be acquired by evaluation of the shape and penetration depth of the diffusion profile of fluorine that was incorporated by the sample from the environment. For a quantitative assessment of the data, several factors like ambient conditions and diagenetic state of the material have to be taken into account.

      PubDate: 2012-12-15T09:29:36Z
       
  • Chapter 8 Fluorine and Its Relevance for Archaeological Studies
    • Abstract: 2006
      Publication year: 2006
      Source:Advances in Fluorine Science, Volume 2

      This paper represents a review of the importance of studying fluorine (F) in archaeological artefacts. Fluorine is an element which is omnipresent in water and soil environments. Thus, it is incorporated into archaeological artefacts as bones or flints in different ways during their burial depending on the geochemical conditions and on the artefact conservation state. The incorporation pathways of F lead to different F distribution patterns in the artefacts. Therefore, these artefacts can be considered as geochemical archives for the reconstruction of their burial history. Moreover, studies of F in ancient bone material or flints can give precious information that are relevant for archaeological purposes as e.g. post-mortem diagenesis. In some cases, relative dating or evidence for heat processes of artefacts is possible. In the introduction, the paper gives a review of general questions in archaeology and relevant examples where analytical studies can give answers to. Then, ancient materials where F is found are presented. The study of F in archaeology is particularly important for materials as bones and flints. Therefore, the majority of the paper is dedicated to the study of these materials and the information deduced on the past. The knowledge of the composition and structure of both types of material is necessary for the understanding of the F incorporation, and is briefly reviewed. Furthermore, postulated incorporation mechanisms of the F uptake over time are reported. In the next paragraph, the most commonly applied analytical methods for F detection in archaeological artefacts are presented. Specific problems related with the analysis of precious and unique artefacts are discussed. Significant archaeological case studies are shown and discussed to highlight the importance of F studies in archaeological artefacts. However, these examples enable us to evidence the limits of F relevance in archaeology and the precautions to take when using these data for archaeological interpretations. Finally, conclusions and an outlook are presented.

      PubDate: 2012-12-15T09:29:36Z
       
  • List of Contributors
    • Abstract: 2006
      Publication year: 2006
      Source:Advances in Fluorine Science, Volume 1



      PubDate: 2012-12-15T09:29:36Z
       
  • Foreword
    • Abstract: 2006
      Publication year: 2006
      Source:Advances in Fluorine Science, Volume 1



      PubDate: 2012-12-15T09:29:36Z
       
  • Introduction to “Fluorine and the Environment”
    • Abstract: 2006
      Publication year: 2006
      Source:Advances in Fluorine Science, Volume 1



      PubDate: 2012-12-15T09:29:36Z
       
  • Chapter 1: Fluorine in the Atmosphere
    • Abstract: 2006
      Publication year: 2006
      Source:Advances in Fluorine Science, Volume 1

      Scientific evidence, accumulated over more than two decades of study by the international research community, has shown that human-produced halocarbons are responsible for the observed depletions of the ozone layer. Fluorine-containing chlorofluorocarbons (CFCs) and halons are sufficiently long-lived so as to reach the stratosphere where they are photodissociated to release chlorine, bromine, and fluorine atoms. Although chlorine and bromine have been proven to be main responsible for the destruction of the ozone layer in the polar regions, fluorine by itself does not contribute to ozone depletion. Fluorine atoms released from the photodissociation of fluorine-bearing sources are quickly sequestered into carbonyl compounds and subsequently into the ultimate hydrogen fluoride, which is very stable in the stratosphere. The primary interest in monitoring inorganic fluorine (defined as F y ) in the atmosphere is as a surrogate of the amounts of its precursors, mainly the CFCs and hydrochlorofluorocarbons, involved in ozone depletion by chlorine. Fluorinated halocarbons and other gases such as perfluorocarbons or sulfur hexafluoride (SF6) are also extremely potent greenhouse gases for which the current trends must be monitored and future scenarios of growth must be evaluated.

      PubDate: 2012-12-15T09:29:36Z
       
  • Chapter 2: Evaluation and Selection of CFC Alternatives
    • Abstract: 2006
      Publication year: 2006
      Source:Advances in Fluorine Science, Volume 1

      This chapter reports on the effect of fluorine compounds in the atmosphere. These compounds have been evaluated for their role in ozone layer depletion and global warming. The state of their application, the use of alternatives and the alternatives themselves were analyzed. There are also explanations of the science behind ozone depletion potential and global-warming potential, of associated evaluation methods, and new methods that can compensate for previous deficiencies. The results suggest that fluorine compounds with short atmospheric lifetimes are suitable as chlorofluorocarbon alternatives.

      PubDate: 2012-12-15T09:29:36Z
       
  • Chapter 3: Trifluoromethyl Sulphur Pentafluoride, SF5CF3: Atmospheric
           Chemistry and Its Environmental Importance via the Greenhouse Effect
    • Abstract: 2006
      Publication year: 2006
      Source:Advances in Fluorine Science, Volume 1

      One molecule of SF5CF3, an adduct of the SF5 and CF3 free radicals, causes more global warming than one molecule of any other greenhouse gas yet detected in the atmosphere, that is, it has the highest per molecule radiative forcing of any greenhouse pollutant, and the value of its global warming potential is only exceeded by that of SF6. Using tunable vacuum-UV radiation from a synchrotron and coincidence spectroscopy, the strength of the central S−C bond in SF5CF3 is determined to be 3.86 ± 0.45eV or 372 ± 43 kJ mol−1, and this molecule is highly unlikely to be removed from the Earth's atmosphere by UV photolysis in the stratosphere. Complementary laboratory-based experiments have shown that the main sink route of this greenhouse gas is low-energy electron attachment in the mesosphere, with Lyman-α photodissociation at 121.6nm being only a minor channel. On comparison with data for SF6, the lifetime of SF5CF3 in the Earth's atmosphere is estimated to be ca. 1000 years. The principal reason for the current low level of concern about the impact of SF5CF3 on our environment is that the concentration levels are still very low, at the sub parts per trillion level. The high growth rate of ca. 6% per annum, however, should cause concern for policymakers.

      PubDate: 2012-12-15T09:29:36Z
       
  • Chapter 4: Production of Second- or Third-Generation Fluorine-based
           Refrigerants from (Photo)-Dechlorination of Fluorocarbon Wastes
    • Abstract: 2006
      Publication year: 2006
      Source:Advances in Fluorine Science, Volume 1

      Chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) are called first-generation fluorocarbons because they contain chlorine atoms. Because they deplete the ozone layer, the production of CFCs has been banned and HCFCs will soon share the same fate. From this trend one can predict that hundreds of thousands of tons of CFCs or HCFCs presently being used will become harmful wastes in the near future. On the other hand, if these chlorinated wastes could be converted into either nonhazardous or useful compounds, CFCs or HCFCs could be regarded as chemical feedstocks. In this work, our first objective was to develop a decomposition method for CFCs or HCFCs at moderate conditions. Combustion of CFCs is an obvious choice, but has the disadvantage of producing toxic compounds such as dioxins. In our work, we found that photodecomposition of chlorinated compounds in dissolved alcohol–NaOH solutions under ultraviolet (UV) irradiation is possible under mild conditions of room temperature and atmospheric pressure. Chlorine atoms are easily removed yielding NaCl. Among the 12 chlorinated compounds tested, low-pressure mercury lamps were more effective than high-pressure ones. Chlorodifluoromethane (HCFC-22) and dichlorotrifluoroethane (HCFC-123a) is decomposed by only bubbling into methanol–NaOH solution and did not require UV irradiation. The second objective of our work was to determine the reaction products and their possible application to environmental fields. Three kinds of solutions, methanol plus NaOH, 2-propanol plus NaOH, and 2-propanol, were tested using 10 types of CFCs and HCFCs. Results showed that the main products were either hydrofluorocarbons (HFCs) or fluoroethers. HFCs are known as second-generation fluorocarbons because – although they have low effects on the ozone layer – they still have a large greenhouse gas potential. Fluoroethers are known as third-generation refrigerants, because they have neither the ozone layer depleting potential nor the greenhouse gas potential. Our work showed the possibility that wastes such as CFCs and HCFCs could be converted into resources. From our results, a possible system for producing 1,1-difluoromethyl ether, CH3OCHF2, is via HCFC-22, because the reaction occurs in the absence of UV irradiation at room temperature and atmospheric pressure, and is widely used in air conditioners. As vapor pressure of the ether is similar to that of chlorodifluoroethane (HCFC-142b), the ether has a good possibility of use as an alternative refrigerant for HCFC-142b. The third objective of our work was to know the effect of process factors such as agitation in addition to reaction mechanism for designing a photochemical reactor. The process is composed of two steps: a mass transfer process of fluorocarbons dissolving in solutions from vapor bubbles and the reaction rate in a solution. To estimate the mass transfer, we measured the solubility of fluorocarbons in alcohol–NaOH solutions. Using these values, a stationary state model, in which mass transfer rates and reaction rates are balanced, was set up. Using the stationary state model with the kinetic data, we obtained a model for the reaction rate and were able to propose a reaction mechanism.

      PubDate: 2012-12-15T09:29:36Z
       
  • Chapter 5: Volcanic Fluorine Emissions: Observations by Fourier Transform
           Infrared Spectroscopy
    • Abstract: 2006
      Publication year: 2006
      Source:Advances in Fluorine Science, Volume 1

      Volcanoes are an important natural source of fluorine to the environment. For several decades, fluorine emissions from volcanoes have been measured by laboratory analysis of samples collected in situ, and abundances compared with other gas species to infer magmatic and hydrothermal processes occurring at depth. More recently, open-path Fourier transform infrared (OP-FTIR) spectroscopy has been applied to field measurements of volcanic gas plumes, offering several advantages including the ability to detect and quantify simultaneously, and with high time resolution, many volcanic gas species. These include hydrogen fluoride (HF) and silicon tetrafluoride (SiF4), and potentially other F-bearing gases. Such measurements yield valuable insights into the degassing of fluorine from magmas and contribute to our understanding of the environmental impacts of volcanic emissions.

      PubDate: 2012-12-15T09:29:36Z
       
  • Chapter 6: Fluorine and Coexisting Volatiles in the Geosphere: The Role in
           Japanese Volcanic Rocks
    • Abstract: 2006
      Publication year: 2006
      Source:Advances in Fluorine Science, Volume 1

      Comprehensive knowledge of the volatile behavior in volcanic rocks is of great value to clarify the process of magma generation and differentiation. However, few studies on volatile elements, particularly the fluorine content in volcanic rocks, have been made because of the difficulties of the analytical technique. In the present research, two types of analytical techniques have been investigated. One is a progressed separation method of distillation with potentiometric determination and the other is a chromatographic method combined with cation-exchange pretreatment. Using the above techniques, fluorine was determined on the 113 volcanic rocks obtained from various parts of Japanese islands. In addition, the other volatile and major elements were also determined on 44 different samples. The analytical results were geochemically interpreted using multivariate analysis in the light of magma generation theory in the subduction zones. The geographical distribution of volatile elements showed that the chemical contents were more related to the source of the elements rather than the chemical property or ionic radius. The factor structure of volatile elements led to the following findings: (1) seawater components brought by subducting slab have a significant influence on the behavior of chlorine, bromine, boron, and arsenic; (2) fluorine and sulfur are mainly contributed by the mantle components.

      PubDate: 2012-12-15T09:29:36Z
       
  • Chapter 7: Fluorine Compounds in Gaseous Emissions from Industrial
           Sources: The Case of Ceramic Industries
    • Abstract: 2006
      Publication year: 2006
      Source:Advances in Fluorine Science, Volume 1

      This chapter assesses fluorine emissions as an atmospheric pollutant that originated from the clay-based raw material used in ceramic industries. After a short review on the production technology of ceramic products, the main features of fluorine emission in firing processes are outlined. It is demonstrated that the emission rate of fluorine increases with the increasing fluorine content in the raw material and the firing temperature. A roundup of methods has been reported for emission sampling and analysis of fluorine content both in gaseous emission and in clay raw materials. The fluorine content of clays on an average is much the same as the one typically found in the Earth's crust, as shown by different studies reported in this work; hence, clays cannot be considered as a major source of fluoride. However, due to the large amount of clays used, the total emission needs to be under control: a detailed review of principal abatement techniques usually used in the ceramic sector is described, in order to underline the different abatement efficiency. A very brief summary of diseases caused in animals and plants by an excess of fluoride in water and atmosphere is also presented.

      PubDate: 2012-12-15T09:29:36Z
       
  • Chapter 8: Some Problems Relating to Fluorides in the Environment: Effects
           on Plants and Animals
    • Abstract: 2006
      Publication year: 2006
      Source:Advances in Fluorine Science, Volume 1

      Several aspects of fluorides in the environment have been researched for decades so there is a great deal of published information. However, the authors consider that there are several important areas where information is lacking, data are contradictory, mechanisms of action have not been explored, or the environmental effects of particular compounds are not known. Therefore, this chapter reviews a selection of such topics: inorganic fluorides in soil; the loss of fluorides from plants; classifying species sensitivity to HF; estimating effects of fluorides on growth and yield; the significance of pollutant interactions; effects of HF on fertilization and seed set; fluorides and insects; and old and new problems associated with organofluorides in the environment.

      PubDate: 2012-12-15T09:29:36Z
       
 
 
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