Download or read book Contribution la microscopie thermique sonde locale en mode alternatif Caract risation de la r ponse et de l interaction sonde chantillon written by Olivier Raphaël and published by . This book was released on 2008 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: La microscopie thermique à sonde locale permet l’étude des champs de température et des propriétés thermiques des matériaux aux échelles micro et nanométrique. Les performances de cet instrument dépendent essentiellement du type de sonde thermique utilisé. Notre microscope emploie une sonde thermo-résistive fabriquée à partir d’un fil de Wollaston de 75 μm de diamètre contenant une âme en platine-rhodium (90% - 10%) de 5 μm de diamètre. Traditionnellement cette sonde est alimentée par un courant électrique continu. Ces travaux de thèse reposent sur la mise en œuvre du mode de fonctionnement à courant alternatif. Un dispositif électronique est spécialement développé pour ce mode de fonctionnement et permet une modélisation précise de la mesure. Deux modélisations distinctes sont présentées : l’une est unidimensionnelle (approche analytique), l’autre est tridimensionnelle (méthode des éléments finis). Elles permettent la caractérisation des propriétés thermo-physiques et géométriques de la sonde remettant en cause les valeurs usuelles, et l’étude des interactions de la sonde avec divers milieux environnants. Les études expérimentales et théoriques de la réponse de la sonde en fonction de la distance la séparant de l’échantillon aboutissent, entre autre, à la mise en évidence d’un phénomène d’interférences d’ondes de diffusion thermique. L’étude de la réponse de la sonde en contact conduit à l’estimation d’une plage de sensibilité à la conductivité thermique de l’échantillon ainsi qu’à l’estimation de la résistance thermique de contact. Enfin l’étude de matériaux comportant des inclusions démontre l’adéquation du mode alternatif avec la caractérisation des couches minces
Download or read book Microscopie thermique sonde locale written by Patricia Al alam and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: La microscopie thermique est un outil prometteur permettant d'étudier les mesures thermiques de matériaux et les mécanismes de transfert de chaleur aux micro/nanoéchelles. La réponse thermique de la sonde a été étudiée en utilisant deux sondes résistives : Wollaston et Palladium. Un modèle en 3D réaliste a été développé pour la sonde Wollaston et l'échantillon avec leur milieu environnant. La simulation de la sonde prend en compte son support et considère que le milieu environnant est convectif. La réponse de la sonde a été évaluée lors de l'approche vers un échantillon de cuivre. La comparaison avec les résultats expérimentaux montre que la prise en compte de la convection naturelle pour le milieu environnant est une hypothèse valide. Nous présentons ensuite une méthodologie pour étudier le signal thermique de la sonde en contact avec un échantillon nanostructuré. Pour cela, nous avons utilisé un échantillon composé de marches de silicium sous une couche de SiO2. SThM s'avère être un outil puissant pour effectuer l'imagerie sub-surfacique. Nous avons montré que le signal thermique obtenu par la sonde est influencé par la présence de structures internes et correspond à un volume sondé qui tient en compte les propriétés thermiques des matériaux. Avec notre modèle, nous avons pu reconstruire le profil expérimental obtenu par SThM. Pour la sonde en Palladium, la réponse de la sonde a été étudiée expérimentalement sous conditions ambiantes en mode alternatif. L'analyse des résultats a mis en évidence la présence d'un phénomène interpréter comme une résonance d'onde thermique qui prend place au micro/nanoéchelle. Ce phénomène est lié à la longueur de diffusion thermique du milieu environnant (air) et indépendant des propriétés thermiques de l'échantillon.
Download or read book D veloppement de la microscopie thermique sonde locale pour la d termination de la conductivit thermique de films minces written by Laurent David and published by . This book was released on 2006 with total page 315 pages. Available in PDF, EPUB and Kindle. Book excerpt: Afin de comprendre et de caractériser les phénomènes de transport de l'énergie thermique aux échelles micro- et submicro-métriques, la microscopie thermique à sonde locale (Scanning Thermal Microscopy : SThM) est prometteuse. Basée sur l’analyse de l’interaction thermique entre une sonde chauffée et un échantillon, elle offre la possibilité de sonder la matière au niveau de volumes de taille micrométrique. Ce travail concerne plus particulièrement l’étude de la conductivité thermique de films minces. Nous proposons un nouveau modèle de prédiction de la mesure. Celui-ci permet non seulement l’étalonnage de la méthode pour la mesure de la conductivité thermique de matériaux massifs mais également de préciser le couplage thermique sonde – échantillon ainsi que d’estimer, à partir de son inversion, la conductivité thermique de films minces. Cette nouvelle approche de la mesure a permis la détermination de la conductivité thermique de films minces de silicium mésoporeux d’épaisseurs micro- et submicrométriques. Pour les épaisseurs de films plus faibles, nous apportons de nouvelles données. Notre modèle a permis une meilleure définition de la résolution en profondeur de l'appareil. Nous avons également développé la technique par la mise sous vide du SThM. Nos premiers résultats sont encourageants et valident la description du couplage utilisé dans notre modèle. Notre méthode a été appliquée à l'étude de céramiques envisagées dans la composition de futurs combustibles nucléaires. Du fait des limitations du SThM, des mesures ont également été entreprises avec un microscope thermique à photoréflectance. Nos résultats permettent de proposer une première estimation de la dégradation de la conductivité thermique, provoquée par une irradiation aux ions lourds, des céramiques considérées.
Download or read book Microscopie thermique sonde locale written by Eloise Guen and published by . This book was released on 2020 with total page 235 pages. Available in PDF, EPUB and Kindle. Book excerpt: La microscopie thermique à sonde locale (SThM) est une technique qui permet de caractériser les propriétés thermiques de nanomatériaux et de mieux comprendre les transferts thermiques existants aux échelles sub-micrométriques. Pour correctement interpréter les mesures, les paramètres influençant le transfert thermique entre la pointe-sonde SThM et l'échantillon sont étudiés. Trois sondes résistives de SThM, se différenciant notamment par leur rayon de courbure micro ou nanométrique, sont tout d'abord caractérisées, et une méthodologie systématique de mesure en régime continu est proposée. Il est observé que la zone de sensibilité à la conductivité thermique des matériaux massifs plans est limitée à quelques W.m-1.K-1 pour toutes les pointes. Pour les matériaux les plus conducteurs, la mesure SThM est dominée par la résistance thermique de contact. Le transfert thermique par le (les) nanocontact(s) solide-solide entre la pointe et l'échantillon est dû à un transport conductif à la fois diffusif et balistique dans l'échantillon. Il est mis en évidence que la rugosité de surface impacte fortement la mesure SThM, diminuant le transfert thermique par le contact de plus de 50 % dans certains cas. Ces travaux sont mis à profit pour des caractérisations de nanomatériaux. La détermination de la conductivité thermique de couches minces de SiO2 sur substrat de silicium indique que les épaisseurs de quelques nanomètres jusqu'à 1 μm sont détectées par certaines pointes. La mesure de températures de changement de phase par microscopie SThM est également étudiée à l'aide d'un étalonnage sur des polymères massifs. L'application de cet étalonnage pour la caractérisation de couches minces de polymère confirme l'influence du substrat et de l'épaisseur de la couche sur la température déterminée par la pointe SThM. Ces travaux démontrent que la microscopie thermique permet d'obtenir des mesures quantitatives.
Download or read book Mod lisation et laboration des m trologies de microscopie thermique sonde locale r sistive written by Stéphane Lefèvre (thermicien).) and published by . This book was released on 2004 with total page 199 pages. Available in PDF, EPUB and Kindle. Book excerpt: Les nouvelles avancées dans le domaine des microsystèmes et des nanostructures amènent en particulier à repenser les métrologies thermiques. Le but de cette thèse est de maîtriser, par la modélisation, une microscopie à force atomique instrumentée d'une sonde thermique pour estimer la conductivité thermique d'un échantillon à l'échelle submicrométrique. Nous avons d'abord établi un modèle analytique compact et complet permettant de comprendre les phénomènes impliqués dans cette métrologie lorsque la pointe est chauffée en régime continu. Nous avons ainsi caractérisé le domaine d'utilisation et les limitations de ce microscope. Nous avons ensuite conçu et modélisé un nouveau procédé opérant en régime périodique pour mesurer de manière plus précise les propriétés thermiques locales. L'analyse rétrospective de nos résultats a conduit enfin à une identification des contributions de chaque mode de transfert entre la pointe et l'échantillon ainsi que leur surface d'échange respective.
Download or read book Adhesion Between Polymers and Concrete Adh sion Entre Polym res Et B ton written by H. R. Sasse and published by Springer. This book was released on 1986 with total page 792 pages. Available in PDF, EPUB and Kindle. Book excerpt: Preface Adhesion is a phenomenon architects and civil engineers are not very familiar with. In other disciplines knowledge about surface properties and the background of bonding energies is also far from satisfactory; nevertheless there are many important· applications in concrete engineering, where adhesion is necessary for success and durability. These include: - coating and painting - repair of concrete surfaces - bonding of fresh to old concrete - crack injection - glueing of precast elements - glueing of steel to concrete, etc. In 1981 RILEM established the technical committee 52-RAC 'Resin Adherence to Concrete'. The main aims of the committee's work were - to collect research results and practical experiences - to initiate and coordinate research programs - to develop, on a scientific base, test methods for field and for laboratory purposes. One of the results of the committee's work is a state-of-the-art report, which will be presented orally as a General Report at the International Symposium ISAP '86, and will be printed either in the RILEM journal Materials and Structures or separately. Several test recommendations have been elaborated and will be prepared as drafts for the participants ofISAP '86. These are: - direct tensile test - pull-off test - direct shear test - slant shear test - four-point bending test - dynamic loading test - thermal compatibility test (two versions) - injectibility test.
Download or read book Quantum Mechanics Volume 3 written by Claude Cohen-Tannoudji and published by John Wiley & Sons. This book was released on 2019-12-16 with total page 790 pages. Available in PDF, EPUB and Kindle. Book excerpt: This new, third volume of Cohen-Tannoudji's groundbreaking textbook covers advanced topics of quantum mechanics such as uncorrelated and correlated identical particles, the quantum theory of the electromagnetic field, absorption, emission and scattering of photons by atoms, and quantum entanglement. Written in a didactically unrivalled manner, the textbook explains the fundamental concepts in seven chapters which are elaborated in accompanying complements that provide more detailed discussions, examples and applications. * Completing the success story: the third and final volume of the quantum mechanics textbook written by 1997 Nobel laureate Claude Cohen-Tannoudji and his colleagues Bernard Diu and Franck Laloë * As easily comprehensible as possible: all steps of the physical background and its mathematical representation are spelled out explicitly * Comprehensive: in addition to the fundamentals themselves, the books comes with a wealth of elaborately explained examples and applications Claude Cohen-Tannoudji was a researcher at the Kastler-Brossel laboratory of the Ecole Normale Supérieure in Paris where he also studied and received his PhD in 1962. In 1973 he became Professor of atomic and molecular physics at the Collège des France. His main research interests were optical pumping, quantum optics and atom-photon interactions. In 1997, Claude Cohen-Tannoudji, together with Steven Chu and William D. Phillips, was awarded the Nobel Prize in Physics for his research on laser cooling and trapping of neutral atoms. Bernard Diu was Professor at the Denis Diderot University (Paris VII). He was engaged in research at the Laboratory of Theoretical Physics and High Energy where his focus was on strong interactions physics and statistical mechanics. Franck Laloë was a researcher at the Kastler-Brossel laboratory of the Ecole Normale Supérieure in Paris. His first assignment was with the University of Paris VI before he was appointed to the CNRS, the French National Research Center. His research was focused on optical pumping, statistical mechanics of quantum gases, musical acoustics and the foundations of quantum mechanics.
Download or read book Faecal Sludge Management written by Linda Strande and published by IWA Publishing. This book was released on 2014-08-15 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is estimated that literally billions of residents in urban and peri-urban areas of Africa, Asia, and Latin America are served by onsite sanitation systems (e.g. various types of latrines and septic tanks). Until recently, the management of faecal sludge from these onsite systems has been grossly neglected, partially as a result of them being considered temporary solutions until sewer-based systems could be implemented. However, the perception of onsite or decentralized sanitation technologies for urban areas is gradually changing, and is increasingly being considered as long-term, sustainable options in urban areas, especially in low- and middle-income countries that lack sewer infrastructures. This is the first book dedicated to faecal sludge management. It compiles the current state of knowledge of the rapidly evolving field of faecal sludge management, and presents an integrated approach that includes technology, management, and planning based on Sandecs 20 years of experience in the field. Faecal Sludge Management: Systems Approach for Implementation and Operation addresses the organization of the entire faecal sludge management service chain, from the collection and transport of sludge, and the current state of knowledge of treatment options, to the final end use or disposal of treated sludge. The book also presents important factors to consider when evaluating and upscaling new treatment technology options. The book is designed for undergraduate and graduate students, and engineers and practitioners in the field who have some basic knowledge of environmental and/or wastewater engineering.
Download or read book Comprehensive Cervical Cancer Control written by World Health Organization and published by World Health Organization. This book was released on 2006 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: Most women who die from cervical cancer, particularly in developing countries, are in the prime of their life. They may be raising children, caring for their family, and contributing to the social and economic life of their town or village. Their death is both a personal tragedy, and a sad and unnecessary loss to their family and their community. Unnecessary, because there is compelling evidence, as this Guide makes clear, that cervical cancer is one of the most preventable and treatable forms of cancer, as long as it is detected early and managed effectively. Unfortunately, the majority of women in developing countries still do not have access to cervical cancer prevention programmes. The consequence is that, often, cervical cancer is not detected until it is too late to be cured. An urgent effort is required if this situation is to be corrected. This Guide is intended to help those responsible for providing services aimed at reducing the burden posed by cervical cancer for women, communities and health systems. It focuses on the knowledge and skills needed by health care providers, at different levels of care.
Download or read book Satellite Situation Report written by Goddard Space Flight Center. Office of Public Affairs and published by . This book was released on 1977 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Methods of Study in Quantitative Soil Ecology Population Production and Energy Flow written by John Phillipson and published by Blackwell Scientific Publications Limited. This book was released on 1971 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt: The soil and its total metabolism. Plant roots. Plant litter. Heterotrophic microflora. Protozoa. Nematodes. Enchytraeids. Earthworms. Molluscs. A comparison of extraction methods for terrestrial anthropods. Mites. Apterygotes, pauropods and symphylans. Aphids. Ants and termites. Other arthropods.
Download or read book World Health Organization Guidelines on the Pharmacological Treatment of Persisting Pain in Children with Medical Illnesses written by World Health Organization and published by . This book was released on 2012 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: These guidelines have been developed to support countries to relieve pain in their paediatric populations. These guidelines address persisting pain in children caused by conditions such as cancer, HIV/AIDS, sickle-cell disease, burns, trauma, and phantom limb pain. Recommendations -- developed following a careful and transparent appraisal of available evidence -- are presented for the pharmacological treatment of mild, moderate and severe pain. The guidelines include chapters on the various systems used to classify pain and on the evaluation of pain, which reviews the available tools for routine pain measurement in children. Provision of sustainable pain relief within health care systems is covered in a separate chapter. Since morphine and other opioid analgesics -- required for the relief of moderate-to-severe pain in children -- are listed under the 1961 UN Single Convention on Narcotic Drugs, the new guidelines include an annex explaining the Convention's requirements for the handling and procurement of opioid analgesics for the relief of pain.
Download or read book Cancer Pain Relief written by World Health Organization and published by World Health Organization. This book was released on 1996 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt: The second edition of a guide, which introduced a simple, yet highly effective method for the relief of cancer pain. Thoroughly revised and updated, the new edition further refines the WHO method, which advocates the use of a small number of relatively inexpensive drugs, including morphine. Revisions draw on experiences with millions of patients around the world as well as new knowledge about the specific pain syndromes unique to cancer. Completely new are chapters describing the international system by which morphine and other opioids are made available for medical purposes. The book has two parts. Part one provides a practical guide to the relief of cancer pain, concentrating on drug treatment as the mainstay of pain management. The most extensive section sets out detailed guidelines for the selection and prescribing of non-opioid analgesics, opioid analgesics, drugs for neuropathic pain, and adjuvant drugs for the treatment of adverse effects, the enhancement of pain relief and the management of concomitant psychological disturbances. Information ranges from explanations of how specific drugs work, through the precautions to take in the presence of certain disorders, to a list of factors that influence the effectiveness of opioids. Concerning the use of opioids, readers are reminded that psychological dependence does not occur in cancer patients and that the only correct dose of morphine is the one that relieves the pain. Part two provides a guide to opioid availability. A discussion of the reasons why opioids continue to be underprescribed or difficult to obtain is followed by an explanation of the Single Convention on Narcotic Drugs.
Download or read book Advances in Ecological Research written by and published by Academic Press. This book was released on 1977-09-27 with total page 189 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Ecological Research
Download or read book Historical Dictionary of Iran written by John Henry Lorentz and published by Historical Dictionaries of Asia, Oceania, and the Middle East. This book was released on 2007 with total page 570 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides an overview of specific events, movements, people, political and social groups, places, trends, and chronology. Allows for considerable exploration of a number of historical and contemporary topics and issues. The modern period, defined as 1800-present, is covered extensively.
Download or read book Phytochemicals in Nutrition and Health written by Mark S. Meskin and published by CRC Press. This book was released on 2002-03-19 with total page 221 pages. Available in PDF, EPUB and Kindle. Book excerpt: Are soy isoflavones neuroprotective? Just how different is one species of Echinacea from another? Which phytochemicals will be effective as therapeutic agents in vivo? Supported by solid scientific research, Phytochemicals in Nutrition and Health helps provide answers to these and other probing questions concerning the mechanisms of action associat
Download or read book The Problems of the Arid Zone written by Unesco and published by paris. This book was released on 1962 with total page 510 pages. Available in PDF, EPUB and Kindle. Book excerpt:
