Download or read book Etude de l influence des hydrocarbures aromatiques sur l oxydation des huiles de base written by Alain POTTIER and published by . This book was released on 1977 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book PHENOMENES D OXYDATION DES LUBRIFIANTS MOTEURS A ESSENCE FONCTIONNANT A HAUTE TEMPERATURE written by Xavier Maleville and published by . This book was released on 1993 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: LE BUT DE CETTE THESE EST LA COMPREHENSION DU MECANISME DE L'AUGMENTATION DE LA VISCOSITE DU LUBRIFIANT, ET LA CARACTERISATION DES PRODUITS RESPONSABLES DE CE PHENOMENE, DANS L'ETAPE QUI PRECEDE L'INSOLUBILITE DES PRODUITS. A L'AIDE D'UN TEST D'OXYDATION EN LABORATOIRE, NOUS ETUDIONS LA RESISTANCE A L'OXYDATION D'HUILE DE BASE, L'INFLUENCE DE LA CATALYSE ET LA REPONSE DE CES HUILES AUX ANTIOXYDANTS. NOUS MONTRONS QUE L'HUILE AYANT DE FORTES TENEURS EN CARBONES AROMATIQUES ET EN SOUFRE, AVEC UN ANTIOXYDANT ET CATALYSEE PAR LE FER SOLUBLE, PRESENTE UNE RESISTANCE A L'OXYDATION INFERIEURE AUX AUTRES HUILES DE BASE. ENSUITE, NOUS CARACTERISONS, A L'AIDE DE TECHNIQUES PHYSICO-CHIMIQUES ET DE FRACTIONNEMENT, LES COMPOSES ORGANIQUES FORMES AU COURS DE L'OXYDATION DE L'HUILE: LES PRODUITS VOLATILS, LES PRODUITS LOURDS SOLUBLES ET INSOLUBLES DE L'HUILE OXYDEE. LES CONSTITUANTS POLAIRES DE CES PRODUITS, SONT CONSTITUES D'ESPECES HYDROXYLES, CARBONYLES ET CARBOXYLES. LES PRODUITS VOLATILS SONT FORMES DE COMPOSES OXYGENES LINEAIRES NON SOUFRES, D'EAU, D'ALCANES, AINSI QUE DE CONSTITUANTS OXYGENES CYCLIQUES ET D'AROMATIQUES, PRESENTS UNIQUEMENT POUR LES HUILES MINERALES. LEUR MASSE MOLAIRE MOYENNE EST INFERIEURE A CELLE DE L'HUILE DE BASE. LES ESPECES RESPONSABLES DE L'AUGMENTATION DE LA VISCOSITE SONT LES PRODUITS LOURDS SOLUBLES ET INSOLUBLES DANS L'HUILE OXYDEE. LES PRODUITS SOLUBLES CONTIENNENT DU SOUFRE, ONT 10% D'OXYGENE ET ONT UNE MASSE D'ENVIRON 1000 G/MOL. ILS PROVIENNENT, POUR LES HUILES DE BASE MINERALES, ESSENTIELLEMENT DE L'OXYDATION DES COMPOSES AROMATIQUES. LES PRODUITS INSOLUBLES ONT UNE MASSE MOLAIRE MOYENNE DE 2000 G/MOL, UNE TENEUR EN OXYGENE DE 20% ET UNE FORTE TENEUR EN SOUFRE. LES COMPOSES SOUFRES ET AROMATIQUES D'UNE HUILE MINERALE PARTICIPENT VIVEMENT A LA FORMATION DE PRODUITS INSOLUBLES. FINALEMENT, NOUS AVONS PROPOSE UN MECANISME DE L'AUGMENTATION DE LA VISCOSITE METTANT EN JEU DES INTERACTIONS CHIMIQUES INTERMOLECULAIRES, DES REACTIONS DE CONDENSATION ET FORMATION DE MACROMOLECULES POLAIRES, MACROMOLECULES QUI PERDENT LEUR AFFINITE POUR LE MILIEU ET PRECIPITENT. UNE ETUDE DE LA RESISTANCE A L'OXYDATION, SUR ESSAIS MOTEURS, DE LUBRIFIANTS, FORMULES A PARTIR DE NOS HUILES DE BASE ET A ADDITIVATION IDENTIQUE, CONFIRME NOS RESULTATS, ET MONTRE QU'UN DES PARAMETRES LES PLUS IMPORTANTS DANS LA STABILITE A L'OXYDATION DES HUILES MINERALES FORMULEES EST LE COMPORTEMENT A L'OXYDATION DES HUILES DE BASE ET LEUR REPONSE VIS-A-VIS DES ANTIOXYDANTS, EN PRESENCE DE CATALYSEUR

Download or read book Etude de la d gradation bact rienne des hydrocarbures aromatiques polycycliques en conditions oxiques written by Thierry Nadalig and published by . This book was released on 1998 with total page 215 pages. Available in PDF, EPUB and Kindle. Book excerpt: LA DEGRADATION BACTERIENNE DES HYDROCARBURES AROMATIQUES POLYCYCLIQUES (HAP) EN CONDITIONS OXIQUES A ETE ETUDIEE AVEC UNE COMMUNAUTE BACTERIENNE PROVENANT D'UN SEDIMENT DU PORT D'ARCACHON (SITE ATLANTIQUE) ET AVEC UNE SOUCHE BACTERIENNE PURE PROVENANT D'UN SEDIMENT DU GOLFE DE FOS (SITE MEDITERRANEEN). LES TECHNIQUES MISES EN UVRE EN MICROBIOLOGIE ET EN CHIMIE ANALYTIQUE ONT ETE DEVELOPPEES ET VALIDEES. LES COMPOSES PHENANTHRENIQUES (PHENANTHRENE (P), 2-METHYLPHENANTHRENE (2MP) ET 9-METHYLPHENANTHRENE (9MP)) ONT ETE CHOISIS COMME MODELES DES HAP. L'ETUDE DE LA DEGRADATION DE CES COMPOSES A MIS EN EVIDENCE DES PHENOMENES DE SELECTIVITE. AINSI, LE 9MP EST SIGNIFICATIVEMENT MOINS DEGRADE QUE LE 2MP OU QUE LE P. AU COURS DE LA DEGRADATION D'UNE FRACTION AROMATIQUE DE PETROLE, L'EVOLUTION DES COMPOSES PHENANTHRENIQUES ET DIBENZOTHIOPHENIQUES ALKYLES A ETE ETUDIEE. LES RESULTATS MONTRENT QUE LE NOMBRE ET LA POSITION DES SUBSTITUANTS SUR LES MOLECULES ONT UNE INCIDENCE SUR LA VITESSE DE DEGRADATION DES COMPOSES. AINSI, PLUS UNE MOLECULE EST SUBSTITUEE, PLUS SON TAUX DE DEGRADATION EST FAIBLE. LE 2MP EST DEGRADE PAR LA SOUCHE BACTERIENNE SELON DEUX VOIES METABOLIQUES. LA PREMIERE VOIE EST INITIEE PAR L'OXYDATION DU GROUPEMENT METHYLE PAR UNE ENZYME MONO-OXYGENASE, LA DEUXIEME VOIE EST INITIEE PAR UNE ENZYME DI-OXYGENASE ET CONDUIT A LA DOUBLE OXYDATION D'UN DES CYCLES AROMATIQUES DU 2MP. DES ETUDES DE TOXICITE (TEST D'ECOTOXICITE) ONT ETE MISES EN UVRE POUR DETERMINER L'INFLUENCE POTENTIELLE DE LA BIODEGRADATION DES HAP SUR LA TOXICITE DES MILIEUX. UN SEDIMENT CONTAMINE EN HAP S'EST REVELE PLUS TOXIQUE VIS-A-VIS DE LARVES D'OURSIN APRES LA MISE EN CULTURE AVEC LA SOUCHE BACTERIENNE QUE CE MEME SEDIMENT AVANT LA MISE EN CULTURE AVEC LA SOUCHE BACTERIENNE.

Download or read book tude de l oxydation et la combustion de quelques hydrocarbures aromatiques entrant dans la composition des carburants automobiles written by Anne Roubaud-Bernard and published by . This book was released on 1999 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optimiser l'adéquation entre les carburants reformulés et les moteurs exige impérativement une connaissance précise des mécanismes d'oxydation et du comportement à la combustion de chaque constituant des essences, notamment des aromatiques. Dans ce travail sont étudiés l'oxydation et la combustion de 11 hydrocarbures aromatiques monocycliques typiques de ceux qui entrent dans la composition des carburants : toluène, m., p., o-xylène, 1,2,3., 1,2,4. 1,3,5-triméthylbenzène, éthylbenzène, n-propylbenzène, n-butylbenzène, 2-éthyltoluène. Des schémas réactionnels sont élaborés à partir de mesures menées dans une machine à compression rapide. Les conditions expérimentales sont proches de celles rencontrées dans les moteurs avant l'inflammation, une pression entre 6 et 23 bar, une température entre 600 et 900 K, une richesse de 1 et une dilution égale ou inférieure à celle de l'air. L'étude phénoménologique de l'auto-inflammation permet de classer les hydrocarbures étudiés en deux groupes de réactivité. Le m., le p-xylène et le 1,3,5-triméthylbenzène ont un comportement qui s'apparente à celui du toluène d'une part et le 1,2,4., le 1,2,3-triméthylbenzène, l'éthylbenzène, le n-propylbenzène, le n-butylbenzène et le 2-éthyltoluène ont un comportement proche de celui de l'oxylène, d'autre part. L'identification et la quantification des produits intermédiaires d'oxydation pour l'o-xylène, le 2-éthyltoluène, n-butylbenzène et le toluène ont permis de proposer des schémas réactionnels, applicables entre 600 et 900 K. Il apparaît que plus les chaînes latérales sont proches ou longues, plus il existe de voies compétitives d'oxydation conduisant à la formation de polluants. Afin de mieux approcher les conditions moteurs, le toluène a été étudié en mélange avec le n-pentane. L'aromatique est consommé par le pool de radicaux créé par l'oxydation du n-pentane. La plus grande consommation de l'aromatique entraîne à l'inverse une diminution du taux d'oxydation de l'aliphatique.

Download or read book Etude cin tique de l oxydation de compos s aromatiques written by Gae͏̈lle Pengloan and published by . This book was released on 2001 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: Les carburants commerciaux sont constitués d'une multitude de composés chimiques dont la combustion incomplète dans les moteurs automobiles génère la formation d'imbrûlés. L'objectif de cette étude est d'approfondir nos connaissances sur les mécanismes cinétiques d'oxydation à haute température des hydrocarbures aromatiques, lesquels constituent un famille importante des carburants. La cinétique de combustion du benzène, du toluène, de l'éthylbenzène et du styrène est étudiée aux richesses 0,5, 1 et 1,5, par deux techniques : le réacteur auto-agité par jets gazeux (RPA) et le tube à choc (TAC). En RPA, les mélanges réactionnels, dilués dans N2, sont oxydés à pression atmosphérique, entre 950 et 1400 K. Après prélèvement, à un temps de séjour fixé, la concentration des espèces stables est déterminée, en fonction de la température, par chromatographie en phase gazeuse (CPG/SM, CPG/FID/TCD). En TAC le domaine de température et de pression est plus élevé : 1300

Download or read book tude des proc d s d oxydation avanc s pour le traitement de sols pollu s par des Hydrocarbures Aromatiques Polycycliques written by Paula Tereza De Souza e Silva and published by . This book was released on 2007 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Remediation of soils contaminated by persistent organic pollutants like Polycyclic Aromatic Hydrocarbons (PAHs) have been widely developed after the discovery of thousands of contaminated sites all over the world. Among the organic pollutants, PAHs are considered as biorefractory compounds, relatively immobile in soils, toxic, carcinogenic and mutagenic. Several techniques have been studied to remove these pollutants from soils, as the Advanced Oxidation Processes (AOPs) that have been proposed in recent years. AOPs are considered as an attractive alternative able to clean up matrices contaminated by refractory substances. In this work, AOPs have been studied to assess their efficacy in the oxidation of PAHs contained in four soil samples from Brazil and France. These AOPs were: (i) treatment by Fenton reactant (H2O2 and Fe(II), (ii) Fenton-like reactant, i.e. Fenton reactant without Fe(II) addition, considering that naturally occurring minerals provided Fe(II), (iii) and (iv) the same treatment with UV radiation, so-called photo-Fenton and photo-Fenton like reactions, and eventually (v) potassium permanganate. In each case, the optimal conditions were determined following factorial designs. Moreover, treatment selectivity was investigated, comparing the oxidation of lower and higher molecular weight PAHs. The formation of oxidation by-procducts was also assessed. To finish, the quality of treated soils was evaluated, by measuring the physico-chemical properties and above all by germination and growth experiments with ray grass chosen as a model plant. The objective was to assess if the treatments allowed further revegetation. In all cases, good oxidation results were reached. Concerning the evaluation of soil quality, it was shown that the treatment by KMnO4, was not compatible with further revegetation. Fenton's reactant had a good effect on soil quality for further revegetation.

Download or read book Etude de la d gradation bact rienne des hydrocarbures aromatiques polycycliques en conditions oxiques written by and published by . This book was released on 1998 with total page 215 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book ICREEC 2019 written by Ahmed Belasri and published by Springer Nature. This book was released on 2020-06-10 with total page 659 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book highlights peer reviewed articles from the 1st International Conference on Renewable Energy and Energy Conversion, ICREEC 2019, held at Oran in Algeria. It presents recent advances, brings together researchers and professionals in the area and presents a platform to exchange ideas and establish opportunities for a sustainable future. Topics covered in this proceedings, but not limited to, are photovoltaic systems, bioenergy, laser and plasma technology, fluid and flow for energy, software for energy and impact of energy on the environment.

Download or read book Pesticide Manual written by British Crop Protection Council and published by . This book was released on 1971 with total page 495 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book CANMET Report written by Canada Centre for Mineral and Energy Technology and published by . This book was released on 1981 with total page 566 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book FeHEDTA written by Canada. Pest Management Regulatory Agency and published by . This book was released on 2010 with total page 45 pages. Available in PDF, EPUB and Kindle. Book excerpt: Health Canada's Pest Management Regulatory Agency (PMRA), under the authority of the Pest Control Products Act and Regulations, is proposing full registration for the sale and use of NEU1173H TGAI and the end-use products; NEU1173H RTU with Pull'N Spray Applicator, NEU1173H RTU with Quick Connect Sprayer, NEU1173H RTU, Fiesta Lawn Weed Killer Ready to Spray, Fiesta Lawn Weed Killer, NEU1173H Ready to Spray Large Size, NEU1173H Ready to Spray, NEU1173H Large Size, and NEU1173H, containing the technical grade active ingredient iron present as FeHEDTA (herein referred to as FeHEDTA), to control several broadleaved weed species that commonly occur in turf. This document summarizes PMRA's evaluation. The Overview describes the key points of the evaluation, while the Science Evaluation provides detailed technical information on the human health, environmental and value assessments of NEU1173H TGAI and the end-use products. Before making a final registration decision on FeHEDTA, the PMRA will consider all comments received from the public in response to this consultation document.--Includes text from document.

Download or read book Frontline and Factory written by Roy MacLeod and published by Springer Science & Business Media. This book was released on 2007-05-06 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book represents a first considered attempt to study the factors that conditioned industrial chemistry for war in 1914-18. Taking a comparative perspective, it reflects on the experience of France, Germany, Austria, Russia, Britain, Italy and Russia, and points to significant similarities and differences. It looks at changing patterns in the organisation of industry, and at the emerging symbiosis between science, industry and the military.

Download or read book Multidisciplinary approaches to food and foodways in the medieval Eastern Mediterranean written by Sylvie Yona Waksman and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Arsenic in Drinking Water written by National Research Council and published by National Academies Press. This book was released on 2001-11-26 with total page 241 pages. Available in PDF, EPUB and Kindle. Book excerpt: Having safe drinking water is important to all Americans. The Environmental Protection Agency's decision in the summer of 2001 to delay implementing a new, more stringent standard for the maximum allowable level for arsenic in drinking water generated a great deal of criticism and controversy. Ultimately at issue were newer data on arsenic beyond those that had been examined in a 1999 National Research Council report. EPA asked the National Research Council for an evaluation of the new data available. The committee's analyses and conclusions are presented in Arsenic in Drinking Water: 2001 Update. New epidemiological studies are critically evaluated, as are new experimental data that provide information on how and at what level arsenic in drinking water can lead to cancer. The report's findings are consistent with those of the 1999 report that found high risks of cancer at the previous federal standard of 50 parts per billion. In fact, the new report concludes that men and women who consume water containing 3 parts per billion of arsenic daily have about a 1 in 1,000 increased risk of developing bladder or lung cancer during their lifetime.

Download or read book Oxidative Stress and Redox Regulation written by Ursula Jakob and published by Springer Science & Business Media. This book was released on 2013-03-15 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many physiological conditions such as host defense or aging and pathological conditions such as neurodegenerative diseases, and diabetes are associated with the accumulation of high levels of reactive oxygen species and reactive nitrogen species. This generates a condition called oxidative stress. Low levels of reactive oxygen species, however, which are continuously produced during aerobic metabolism, function as important signaling molecules, setting the metabolic pace of cells and regulating processes ranging from gene expression to apoptosis. For this book we would like to recruit the experts in the field of redox chemistry, bioinformatics and proteomics, redox signaling and oxidative stress biology to discuss how organisms achieve the appropriate redox balance, the mechanisms that lead to oxidative stress conditions and the physiological consequences that contribute to aging and disease.

Download or read book Topics in Romance Syntax written by Osvaldo Jaeggli and published by ISSN. This book was released on 1981 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The architecture of the human language faculty has been one of the main foci of the linguistic research of the last half century. This branch of linguistics, broadly known as Generative Grammar, is concerned with the formulation of explanatory formal accounts of linguistic phenomena with the ulterior goal of gaining insight into the properties of the 'language organ'. The series comprises high quality monographs and collected volumes that address such issues. The topics in this series range from phonology to semantics, from syntax to information structure, from mathematical linguistics to studies of the lexicon. To discuss your book idea or submit a proposal, please contact Birgit Sievert

Download or read book Sustainable Hydrogen Production written by Ibrahim Dincer and published by Elsevier. This book was released on 2016-08-05 with total page 494 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sustainable Hydrogen Production provides readers with an introduction to the processes and technologies used in major hydrogen production methods. This book serves as a unique source for information on advanced hydrogen generation systems and applications (including integrated systems, hybrid systems, and multigeneration systems with hydrogen production). Advanced and clean technologies are linked to environmental impact issues, and methods for sustainable development are thoroughly discussed. With Earth's fast-growing populations, we face the challenge of rapidly rising energy needs. To balance these we must explore more sustainable methods of energy production. Hydrogen is one key sustainable method because of its versatility. It is a constituent of a large palette of essential materials, chemicals, and fuels. It is a source of power and a source of heat. Because of this versatility, the demand for hydrogen is sure to increase as we aim to explore more sustainable methods of energy. Furthermore, Sustainable Hydrogen Production provides methodologies, models, and analysis techniques to help achieve better use of resources, efficiency, cost-effectiveness, and sustainability. The book is intellectually rich and interesting as well as practical. The fundamental methods of hydrogen production are categorized based on type of energy source: electrical, thermal, photonic, and biochemical. Where appropriate, historical context is introduced. Thermodynamic concepts, illustrative examples, and case studies are used to solve concrete power engineering problems. - Addresses the fundamentals of hydrogen production using electrical, thermal, photonic, and biochemical energies - Presents new models, methods, and parameters for performance assessment - Provides historical background where appropriate - Outlines key connections between hydrogen production methods and environmental impact/sustainable development - Provides illustrative examples, case studies, and study problems within each chapter