Download or read book ETUDE DE PROPIETES DE TRANSPORT D UN PLASMA DE MELANGE AIR CUIVRE written by HASSAN.. OUAJJI and published by . This book was released on 1986 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: CALCUL DES COEFFICIENTS DE CONDUCTIVITE THERMIQUE, DE CONDUCTIVITE ELECTRIQUE ET DE VISCOSITE DU MELANGE AIR-CUIVRE A LA PRESSION ATMOSPHERIQUE POUR DES TEMPERATURES COMPRISES ENTRE 5000 K ET 14000 K ET DIFFERENTES VALEURS DE LA TENEUR EN CUIVRE. DANS LES MEMES CONDITIONS DE TEMPERATURE ET DE PRESSION, LA DETERMINATION DE LA COMPOSITION D'EQUILIBRE DU MELANGE MET EN EVIDENCE L'EVOLUTION DE LA POPULATION DES DIFFERENTES ESPECES CHIMIQUES EN PRESENCE EN FONCTION DE LA TENEUR EN CUIVRE. LES CARACTERISTIQUES MACROSCOPIQUES DE LA COLONNE (CHAMP ELECTRIQUE, PROFIL DE TEMPERATURE) SONT OBTENUES A PARTIR DU MODELE ENERGETIQUE DE ELENBAAS-HELLER

Download or read book Etude d un plasma d air ensemenc de vapeurs de cuivre written by Sylvie Bouillon Combadière and published by . This book was released on 1995 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt: CE DOCUMENT A POUR THEME L'ETUDE DE PLASMAS D'AIR ENSEMENCES DE CUIVRE, CREES PAR ARC A HAUTE PRESSION. LA MESURE PAR ACTINOMETRIE DE LA DENSITE D'OXYGENE ATOMIQUE DANS L'ETAT FONDAMENTAL A ETE ETENDUE AU CAS DE MILIEUX A PRESSION INTERMEDIAIRE: ELLE A ETE VALIDEE PAR SPECTROSCOPIE OPTIQUE D'EMISSION JUSQU'A 13 MBARS POUR UN PLASMA GENERE PAR MICRO-ONDES ; LA VALEUR OBTENUE EN PLASMA D'AIR CREE PAR ARC, POUR UNE PRESSION STATIQUE DE 0,3 MBAR, EST COMPARABLE AU RESULTAT DE COMPOSITION FOURNI PAR UNE SIMULATION MONODIMENSIONNELLE DE L'ECOULEMENT. LA CARACTERISATION DU PLASMA D'AIR HAUTE PRESSION EN ECOULEMENT INTERESSE DEUX POINTS DE FONCTIONNEMENTS, DE PRESSIONS STATIQUES 0,6 ET 28 BARS. UN CALCUL PREVISIONNEL REALISE A L'EQUILIBRE THERMODYNAMIQUE A MIS EN EVIDENCE L'INFLUENCE DES IONS CU+ SUR LA COMPOSITION ET LES PROPRIETES DE TRANSPORT DU PLASMA. DES EXPERIMENTATIONS MENEES PAR SPECTROSCOPIE OPTIQUE (EMISSION, ABSORPTION) MONTRENT QUE LA TEMPERATURE D'EXCITATION DE CU EST SYSTEMATIQUEMENT SUPERIEURE A LA TEMPERATURE DE THERMALISATION DES ESPECES LOURDES, QU'AUX PLUS HAUTES PRESSIONS (28 BARS) SES NIVEAUX D'EXCITATION SONT SURPEUPLES PAR RAPPORT A UNE DISTRIBUTION DE BOLTZMANN ET QU'IL ENTRETIENDRAIT DES ECHANGES SELECTIFS D'EXCITATION AVEC N2, N ET O. LA CARACTERISATION PAR SPECTROSCOPIE OPTIQUE D'EMISSION DE L'INTERACTION DU PLASMA EN ECOULEMENT A 28 BARS AVEC UN MATERIAU GRAPHITE MET EN EVIDENCE LA FORMATION EN COUCHE LIMITE DE MOLECULES DE CUO, CE QUI MODIFIERAIT L'OXYDATION DU GRAPHITE. ENFIN, LA PRESENCE DE CU FAVORISERAIT L'IONISATION DE LA COUCHE LIMITE, INTENSIFIANT LES ECHANGES THERMIQUES AVEC LE MATERIAU ET DE FAIT SA DEGRADATION

Download or read book Etude exp rimentale de l influence des vapeurs de cuivre sur les propri t s d un plasma d arc transf r br lant dans l argon la pression atmosph rique written by Lakbir El Hamidi and published by . This book was released on 1994 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: LE TRAVAIL PRESENTE DANS CE MEMOIRE CONSISTE A ETUDIER EXPERIMENTALEMENT LES PERTURBATIONS APPORTEES PAR LA PRESENCE DE VAPEURS DE CUIVRE SUR UN PLASMA D'ARC TRANSFERE BRULANT DANS L'ARGON A LA PRESSION ATMOSPHERIQUE POUR UNE INTENSITE DU COURANT DE 90 A, UNE LONGUEUR D'ARC DE 18 MM ET UN DEBIT DE GAZ DE 8 NI/MN. LA PREMIERE ETAPE INDISPENSABLE A CETTE ETUDE EST LA CONCEPTION ET LA MISE AU POINT D'UN DISPOSITIF A ARC TRANSFERE PERMETTANT D'OBTENIR SOIT UN PLASMA D'ARGON, SOIT UN PLASMA FORME D'UN MELANGE D'ARGON ET DE VAPEURS DE CUIVRE QUI PROVIENT DE L'EROSION DE L'ANODE. LES METHODES DE DIAGNOSTIC DU PLASMA CREE PAR L'ARC SONT FONDEES SUR LA SPECTROSCOPIE D'EMISSION ET LA SPECTROSCOPIE D'ABSORPTION. DANS LE CAS D'UN PLASMA D'ARGON PUR, NOUS AVONS DETERMINE LE CHAMP DE TEMPERATURE DANS TOUT LE VOLUME DE L'ARC QUI A UNE FORME CARACTERISTIQUE DE CLOCHE. PRES DE LA CATHODE OU L'ACCROCHAGE DE L'ARC EST TRES LOCALISE, LA TEMPERATURE DEPASSE 18000 K, ALORS QUE PRES DE L'ANODE LES VALEURS MAXIMUM DE TEMPERATURE SONT DE L'ORDRE DE 11000 K. D'AUTRE PART, DES ECARTS A L'EQUILIBRE ONT ETE MIS EN EVIDENCE DANS LES ZONES EXTERNES DE L'ARC. LORSQUE L'ANODE EST FAIBLEMENT REFROIDIE, UNE ZONE DE PLASMA DE 3 MM D'EPAISSEUR, JUSTE AU-DESSUS DE L'ELECTRODE EST INFLUENCEE PAR LA VAPEUR DE CUIVRE. NOS RESULTATS MONTRENT QU'AVEC UNE CONCENTRATION DE CUIVRE INFERIEURE A 1% (EN VOLUME) LE PLASMA SUBIT UN REFROIDISSEMENT DE 2000 K ENVIRON. CET EFFET EST DU AUX MODIFICATIONS DES PROPRIETES LOCALES DU PLASMA DUES AU CUIVRE, TELLES QUE L'AUGMENTATION DE LA CONDUCTIVITE ELECTRIQUE ET DU RAYONNEMENT EMIS. ENFIN LES VARIATIONS DE TENSION DE L'ARC SONT ANALYSEES EN FONCTION DES PROPRIETES LOCALES DU PLASMA ET DES CONDITIONS D'ACCROCHAGE DE L'ARC A L'ANODE

Download or read book ETUDE DE L INFLUENCE DES VAPEURS DE CUIVRE SUR LE PLASMA D UN ARC ELECTRIQUE AU VOISINAGE DES ELECTRODES written by HASSAN.. ABDELHAKIM IBRAHIM and published by . This book was released on 1982 with total page 149 pages. Available in PDF, EPUB and Kindle. Book excerpt: APRES UN BREF RAPPEL DE THEORIE CINETIQUE DES GAZ, LES EXPRESSIONS NECESSAIRES AU CALCUL DES COEFFICIENTS DE TRANSPORT DANS UN PLASMA AZOTE-CUIVRE SONT ETABLIES. LES SECTIONS EFFICACES QUI N'ONT PU ETRE TROUVEES DANS LA LITTERATURE SONT CALCULEES. LE DEUXIEME CHAPITRE EST CONSACRE AU CALCUL DES INTEGRALES DE COLLISIONS QUI PERMETTENT DE DETERMINER LES VALEURS DES COEFFICIENTS DE TRANSPORT EN FONCTION DE LA TEMPERATURE POUR PLUSIEURS POURCENTAGES DE CUIVRE DANS L'AZOTE: COEFFICIENTS DE CONDUCTIVITE ELECTRIQUE ET THERMIQUE, DIFFUSION, VISCOSITE. LE CHAPITRE IV EST CONSACRE AUX RESULTATS EXPERIMENTAUX. LA TEMPERATURE ET LA REPARTITION DE CUIVRE DANS LA DECHARGE SONT AINSI DETERMINEES POUR PLUSIEURS CONDITIONS DE FONCTIONNEMENT. DANS LE CINQUIEME CHAPITRE, CES VALEURS SONT COMPAREES A CELLES OBTENUES PAR LE CALCUL EN UTILISANT UN MODELE MACROSCOPIQUE DE BILAN D'ENERGIE

Download or read book Etude des propri t s thermodynamiques et de transport dans les plasmas thermiques l quilibre et hors d quilibre thermodynamiques written by Jacques Aubreton and published by . This book was released on 1985 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Contribution l tude des propri t s des plasmas deux temp ratures written by Hugues Hingana and published by . This book was released on 2010 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dans le domaine des plasmas thermiques, de nombreux procédés industriels sont caractérisés en supposant l'équilibre thermique. Cependant ces conditions d'équilibre ne sont pas remplies près des bords des plasmas crées par des arcs électriques ou des jets de plasmas. Les écarts à l'équilibre modifient alors considérablement la cinétique chimique du milieu et peuvent affecter le procédé étudié. La compréhension, l'analyse et la prédiction de ces procédés demandent alors une modélisation physique du plasma à deux températures (2T). Cette modélisation s'appuie sur le calcul préalable des propriétés du plasma 2T, calcul qui fait l'objet de cette thèse. La première partie de ce travail est consacrée au calcul de la composition d'un plasma à 2T. Il existe dans la littérature plusieurs théories permettant de calculer les densités des espèces pour un plasma hors équilibre mais l'originalité de ce travail se trouve dans l'établissement d'une loi " pseudo cinétique " régissant le peuplement des espèces. La seconde partie concerne le calcul des propriétés thermodynamiques. Elle s'appuie sur une étude bibliographique des méthodes de calcul déjà existantes et des données indispensables à l'obtention de telles propriétés. Un effort particulier est fait pour séparer les contributions des électrons et celles des particules lourdes dans les échanges d'énergie. La dernière partie de cette thèse est dédiée aux calculs des coefficients de transport. Nous évoquons les grandes lignes de calculs des propriétés intermédiaires avant de présenter les différentes théories existantes dans la littérature. Tous les résultats ont été validés par confrontation du calcul à l'ETL avec la littérature.

Download or read book Atmospheric Corrosion written by Christofer Leygraf and published by John Wiley & Sons. This book was released on 2016-06-07 with total page 401 pages. Available in PDF, EPUB and Kindle. Book excerpt: ATMOSPHERIC CORROSION Presents a comprehensive look at atmospheric corrosion, combining expertise in corrosion science and atmospheric chemistry Atmospheric corrosion has been a subject of engineering study, largely empirical, for nearly a century. Scientists came to the field rather later on and had considerable difficulty bringing their arsenal of tools to bear on the problem. Atmospheric corrosion was traditionally studied by specialists in corrosion having little knowledge of atmospheric chemistry, history, or prospects. Atmospheric Corrosion provides a combined approach bringing together experimental corrosion and atmospheric chemistry. The second edition expands on this approach by including environmental aspects of corrosion, atmospheric corrosion modeling, and international corrosion exposure programs. The combination of specialties provides a more comprehensive coverage of the topic. These scientific insights into the corrosion process and its amelioration are the focus of this book. Key topics include the following: Basic principles of atmospheric corrosion chemistry Corrosion mechanisms in controlled and uncontrolled environments Degradation of materials in architectural, transport, and structural applications; electronic devices; and cultural artifacts Protection of existing materials and choosing new ones that resist corrosion Prediction of how and where atmospheric corrosion may evolve in the future Complete with appendices discussing experimental techniques, computer models, and the degradation of specific metals, Atmospheric Corrosion, Second Edition continues to be an invaluable resource for corrosion scientists, corrosion engineers, conservators, environmental scientists, and anyone interested in the theory and application of this evolving field. The book concerns primarily the atmospheric corrosion of metals and is written at a level suitable for advanced undergraduates or beginning graduate students in any of the physical or engineering sciences.

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 The Theory of Ionization of Gases by Collision written by Sir John Townsend and published by . This book was released on 1910 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Application of Particle and Laser Beams in Materials Technology written by P. Misaelides and published by Springer Science & Business Media. This book was released on 1995-01-31 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of advanced materials with preselected properties is one of the main goals of materials research. Of especial interest are electronics, high-temperature and superhard materials for various applications, as well as alloys with improved wear, corrosion and mechanical resistance properties. The technical challenge connected with the production of these materials is not only associated with the development of new specialised preparation techniques but also with quality control. The energetic charged particle, electron and photon beams offer the possibility of modifying the properties of the near-surface regions of materials without seriously affecting their bulk, and provide unique analytical tools for testing their quality. Application of Particle and Laser Beams in Materials Technology provides an overview of this rapidly expanding field. Fundamental aspects concerning the interactions and collisions on atomic, nuclear and solid state scale are presented in a didactic way, along with the application of a variety of techniques for the solution of problems ranging from the development of electronics materials to corrosion research and from archaeometry to environmental protection. The book is divided into six thematic units: Fundamentals, Surface Analysis Techniques, Laser Beams in Materials Technology, Accelerator-Based Techniques in Materials Technology, Materials Modification and Synchrotron Radiation.

Download or read book Structural Control of Mineral Deposits written by Alain Chauvet and published by MDPI. This book was released on 2019-04-16 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Structural Control” remains a crucial point that frequently lacks in any scientific and/or economic analysis of ore deposits, whatever their type and class. The case of lode deposits is exemplary, although also other deposits, like breccia pipe, stockwerk, massive sulphides, skarn, etc., can, surprisingly, be concerned. Several concepts like the gold-bearing shear zone have not proven valid during the last few decades in terms of our understanding of gold deposit and have been totally abandoned. Additionally, the relationships between magmatism, regional tectonic context, and mineralization remain uncertain and have been debated in several recent publications. This demonstrates that this issue is still relevant, and its solution may help in the distinction between intrusion-related and orogenic deposits. In this Special Issue, we particularly invite any case study of mineral deposits, in which it has been demonstrated that structural geology may have a significant role in the establishment of the deposit model of formation and/or on exploration and exploitation programs. Examples in which the structural model diverges from those described in the classical literature are particularly welcomed, including studies in which relationships with magmatism can be suspected and/or demonstrated. Indeed, all cases that illustrate concepts that differ from the classic ones and from theoretical models may represent significant contributions to this volume.

Download or read book Pandex Current Index to Scientific and Technical Literature written by and published by . This book was released on 1969 with total page 1502 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bulletin de L Institut International Du Froid written by International Institute of Refrigeration and published by . This book was released on 1990 with total page 888 pages. Available in PDF, EPUB and Kindle. Book excerpt: Some numbers called Special issue and consist of summaries of papers to be presented at the International Congresses of Refrigeration.

Download or read book Nuclear Techniques in Animal Production and Health written by International Atomic Energy Agency and published by . This book was released on 1976 with total page 632 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soil-plant animal relations regarding minerals; Trace elements in animal nutrition; Trace elements in animal nutrition; Calcium; Phosphorus and magnesium metabolism; Protein (nitrogen) metabolism - ruminants; Protein (nitrogen) metabolism - non-ruminants; Nuclear techniques in the control of parasitic infections; Animal endocrinology with special emphasis on radioimmunoassays.

Download or read book Fungicide Resistance in Plant Pathogens written by Hideo Ishii and published by Springer. This book was released on 2015-08-31 with total page 481 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume offers a comprehensive coverage of the general principles and recent advances in fungicide resistance. It describes the development, mechanisms, monitoring, and management of resistance and covers the most important group of fungicides that have caused resistance on various crops. An historical review of fungicide resistance over the past 40 years sets the scene for up-to-date basic information on mode of action, as well as the genetics, mechanisms, and evolution of resistance. Monitoring for resistance, including the latest developments in molecular diagnostics, moves readers into the practical aspects of resistance management, which is dealt with through a series of case studies outlining fungicide-use strategies on several key crops. The chapters reflect the experience of authors internationally recognised for their significant contributions to fungicide resistance research. The majority of crop diseases are caused by fungal pathogens, and disease control relies heavily on chemically synthesized fungicides. However, modern fungicides often encounter the problem of resistance development in target pathogens. Thus pathogen resistance to fungicides is an important factor that causes loss of yield and quality of crops. It often threatens biosecurity through the decrease of fungicide efficacy in the fields. To manage fungicide resistance successfully will require the promotion of integrated disease management, involving not just chemical fungicides, but also host plant resistance, agronomic factors, and reliable biological control agents where these are available. Well referenced throughout, the book offers a comprehensive account of resistance, which will be useful as a source of material for lecturers and for both industrial and academic scientists involved in fungicide resistance research. It is also a valuable sourcebook for students.

Download or read book Mineral Deposits of North Africa written by Mohammed Bouabdellah and published by Springer. This book was released on 2016-06-21 with total page 585 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents an exhaustive overview of major orebodies and mineral deposits of North Africa. It is intended both for academic researchers and especially for exploration geologists interested in mineral exploration in the northern part of the African continent. Recent changes in the mining laws of most countries in this region have encouraged international mining companies to invest in local mineral industries. Accordingly, this volume will be very useful for these professionals, as well as for researchers in the field of economic geology.

Download or read book Mass Spectrometry of Inorganic and Organometallic Compounds written by William Henderson and published by John Wiley & Sons. This book was released on 2005-07-15 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first modern book to treat inorganic and organometallic mass spectrometry simultaneously. It is textbook and handbook in one; as a textbook it introduces the techniques and gives hints on how to apply the various techniques, as a handbook it lists all available ionization techniques for just about any given compound. The book also includes non-mathematical explanations of how modern MS instruments work Mass Spectrometry of Inorganic and Organometallic Compounds will inspire the synthetic inorganic and organometallic chemist with the confidence to apply some of the new techniques to their characterization problems.