Download or read book Etude structurale des hydrates des sulfates d uranyle et d uranium IV written by René Delobel and published by . This book was released on 1970 with total page 69 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Etude sur le chlorure d uranium IV et sur ses hydrates written by Claude Pommier and published by . This book was released on 1966 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book ETUDES STRUCTURALES DE COMPLEXES D URANIUM AVEC DES MACROCYCLES EN PHASE SOLIDE ET EN SOLUTION written by ANNE.. DEJEAN DE LA BATIE MEYER and published by . This book was released on 1986 with total page 175 pages. Available in PDF, EPUB and Kindle. Book excerpt: ETUDE PAR DIFFRACTION RX A L'ETAT SOLIDE, RMN EN SOLUTION ET EXAFS A L'ETAT SOLIDE ET EN SOLUTION DE LA COMPLEXATION DE DIFFERENTS DEGRES D'OXYDATION DE L'URANIUM PAR DES LIGANDS MACROCYCLIQUES

Download or read book Contribution la connaissance de la cristallochimie de l ion uranyle dans les oxydes d uranium hydrates written by Alain Courtois and published by . This book was released on 1968 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: L'étude des structures cristallines de la curite et de la becquerelite a été exécutée par diffraction des rayons X sur des monocristaux de faibles dimensions (épaisseur de l'ordre du centième de millimètre). Les clichés obtenus sur chambre de Weissenberg par la méthode d'équiinclinaison ont montré dans chaque cas l'existence de la symétrie orthorhombique. Les intensités intégrées ont été corrigées des phénomènes de Lorentz et polarisation et des phénomènes d'absorption en assimilant les cristaux à des cylindres. Les nombres de réflexions observées étaient supérieurs à 1000 pour la curite, à 1600 pour la becquerelite. La position des atomes lourds (Uranium ct plomb dans la curite, uranium dans la becquerelite) étant connue, les autres atomes des structures ont été placés à l'aide de sections de Fourier-différences (où l 'on remplace la contribution du facteur de structure par la différence entre les modules des facteurs de structure observé et calculé à l'aide du motif partiel) . Les positions atomiques ont été affinées, avec facteur d'agitation thermique, isotrope et individuel, par la méthode des moindres carrés. Décrite dans le groupe de sym3trie Pnam, la structure cristalline de la curite comporte des couches dont le plan moyen est perpendiculaire au paramètre a, et les atones d'uranium sont situés, dans ce plan, aux nœuds d'un réseau hexagonal légèrement déformé. On remarque deux types d'entourage des atomes d'uranium : perpendiculairement au groupement ionique UO2 existe soit un groupement pratiquement plan de quatre atomes d'oxygène, soit un groupement plan de cinq atomes d'oxygène. Entre les couches ainsi décrites, dans les régions d'écartement maximal, viennent se placer les atomes de plomb. Notre modèle ne permet pas d'expliquer l'existence de plomb statistique à l'échelle atomique, d'autre part, une hypothèse d’interprétation analogue à celle de la becquerelite ne peut pas s'appliquer. Peut-être la solution réside-t-elle dans le choix d'un groupe de symétrie monoclinique. La becquerelite a été décrite dans le groupe Pn21a. Elle comporte une structure analogue en couches de plan moyen perpendiculaire au paramètre c, avec un arrangement presque hexagonal des uraniums dans ce plan. Ces couches sont plus régulières que celles de la curite et les atomes d'uranium possèdent tous le même entourage avec deux liaisons courtes correspondant au groupement rectiligne UO2 et cinq liaisons U-0 plus longues dans un plan perpendiculaire. En outre, parallèlement à ces couches et entre elles existent des couches contenant des molécules d'eau. C'est dans ces couches que se localisent les ions calcium. L'hypothèse d'interprétation rend compte des données expérimentales telles que la courbe thermopondérale de déshydratation et l'existence d'un clivage parfait parallèle au plan des couches. La détermination par diffraction X des structures cristallines comportant des atomes lourds comme l'uranium à côté d'atomes beaucoup plus légers comme l'oxygène est difficile même en disposant d'un grand nombre de données expérimentales (réflexions observées) et de mesures soignées des intensités des taches de diffraction. La précision résultante sur les coordonnées des atomes légers est médiocre. Néanmoins, les distances interatomiques donnent une idée des longueurs de liaisons et les structures proposées, qui font apparaître certaines incompatibilités cristallographiques de détail, permettent de fournir des modèles suffisamment élaborés afin de poursuivre des recherches ultérieures sur ces composés.

Download or read book tude sur le chlourure d uranium IV et sur ses hydrates written by Claude Pommier and published by . This book was released on 1966 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bibliography written by Pierre Villars and published by Walter de Gruyter. This book was released on 2012-12-21 with total page 1827 pages. Available in PDF, EPUB and Kindle. Book excerpt: By browsing about 10 000 000 scientific articles of over 200 major journals mainly in a 'cover to cover approach' some 200 000 publications were selected. The extracted data is part of the following fundamental material research fields: crystal structures (S), phase diagrams (also called constitution) (C) and the comprehensive field of intrinsic physical properties (P). This work has been done systematically starting with the literature going back to 1900. The above mentioned research field codes (S, C, P) as well as the chemical systems investigated in each publication were included in the present work. The aim of the Inorganic Substances Bibliography is to provide researchers with a comprehensive compilation of all up to now published scientific publications on inorganic systems in only three handy volumes.

Download or read book Uranium written by Peter C. Burns and published by Walter de Gruyter GmbH & Co KG. This book was released on 2018-12-17 with total page 696 pages. Available in PDF, EPUB and Kindle. Book excerpt: Volume 38 of Reviews in Mineralogy provides detailed reviews of various aspects of the mineralogy and geochemistry of uranium. We have attempted to produce a volume that incorporates most important aspects of uranium in natural systems, while providing some insight into important applications of uranium mineralogy and geochemistry to environmental problems. The result is a blend of perspectives and themes: historical (Chapter 1), crystal structures (Chapter 2), systematic mineralogy and paragenesis (Chapters 3 and 7), the genesis of uranium ore deposits (Chapters 4 and 6), the geochemical behavior of uranium and other actinides in natural fluids (Chapter 5), environmental aspects of uranium such as microbial effects, groundwater contamination and disposal of nuclear waste (Chapters 8, 9 and 10), and various analytical techniques applied to uranium-bearing phases (Chapters 11-14). This volume was written in preparation for a short course by the same title, sponsored by the Mineralogical Society of America, October 22 and 23, 1999 in Golden, Colorado, prior to MSA's joint annual meeting with the Geological Society of America.

Download or read book The Chemistry of Uranium written by J.J. Katz and published by Рипол Классик. This book was released on 1961 with total page 625 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modelling in Aquatic Chemistry written by OECD Nuclear Energy Agency and published by Nuclear Energy Agency. This book was released on 1997 with total page 788 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Chemical Thermodynamics of Neptunium and Plutonium written by Robert J. Lemire and published by Elsevier. This book was released on 2001-08-26 with total page 876 pages. Available in PDF, EPUB and Kindle. Book excerpt: Unlike earlier books in this series, this review describes the selection of chemical thermodynamic data for species of two elements, neptunium and plutonium. Although this came about more by circumstance than design, it has allowed for a more consistent approach to chemical interpretation than might have occurred in two separate treatments. It has also drawn attention to cases where the available data do not show expected parallels, and where further work may be useful to confirm or refute apparent differences in the behaviour of neptunium and plutonium.

Download or read book INIS Atomindex written by and published by . This book was released on 1984 with total page 1268 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Interpretation of Micromorphological Features of Soils and Regoliths written by Georges Stoops and published by Elsevier. This book was released on 2018-09-17 with total page 1002 pages. Available in PDF, EPUB and Kindle. Book excerpt: Interpretation of Micromorphological Features of Soils and Regoliths, Second Edition, provides researchers and students with a tool for interpreting features observed in soil thin sections and through submicroscopic studies. After an introduction and general overview, micromorphological aspects of regoliths (e.g., saprolites, transported materials) are highlighted, followed by a systematic and coherent discussion of the micromorphological expression of various pedogenic processes. The book is written by an international team of experts in the field, using a uniform set of concepts and terminology, making it a valuable interdisciplinary reference work. The following topics are treated: freeze-thaw features, redoximorphic features, calcareous and gypsiferous formations, textural features, spodic and oxic horizons, volcanic materials, organic matter, surface horizons, laterites, surface crusts, salt minerals, biogenic and pedogenic siliceous materials, other authigenic silicates, phosphates, sulphidic and sulphuric materials, and features related to faunal activity. The last chapters address anthropogenic features,archaeological materials and palaeosoils. - Updates the first exhaustive publication on interpretation of micromorphological features, with some new chapters and with a larger number of additional references - Covers related topics, making micromorphology more attractive and accessible for geomorphologists, archaeologists and quaternary geologists Includes thematic treatment of a range of soil micromorphology fields and broadens its applications - Features input from a multi-disciplinary team, ensuring thorough coverage of topics related to soil science, archaeology and geomorphology

Download or read book Uranium Extraction Technology written by International Atomic Energy Agency and published by . This book was released on 1993 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this publication is to update and expand the first edition, which was published in 1983, and to report on later advances in uranium ore processing. It includes background information about the principles of the unit operations used in uranium ore processing and summarizes the current state of the art. Extensive references provide sources for specific technological details.

Download or read book Uranium written by Peter C. Burns and published by . This book was released on 2013 with total page 437 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Quaternary Vegetation Dynamics written by Jürgen Runge and published by CRC Press. This book was released on 2021-11-28 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book celebrates the relaunch of the African Pollen Database, presents state-of-the-art of modern and ancient pollen data from sub-Saharan Africa, and promotes Open Access science. Pollen grains are powerful tools for the study of past vegetation dynamics because they preserve well within sedimentary deposits and have a huge diversity in ornamentation that allows different taxa to be determined. The reconstruction of past vegetation from the examination of ancient pollen records thus can be used to characterize the nature of past landscapes (e.g. abundance of forests vs. grasslands), provide insights into changes in biodiversity, and gain empirical evidence of vegetation response to climatic change and human activity. In this, the 35th Volume of "Palaeoecology of Africa", we bring together new data and extensive synthetic reviews to provide novel insights into the relationships between human evolution, human activity, climate change and vegetation dynamics during the Quaternary, the last 2.6 million years. Current and ongoing climate and land-use change is exerting pressure on modern vegetation formations and threatening the livelihoods and wellbeing of many peoples in Africa. In this book the focus is on the Quaternary because it is during this geological period that the modern vegetation formations developed into their current configurations against a backdrop of high magnitude global climate change (glacial-interglacial cycles), human evolution, and a growing human land-use footprint. In this book the latest information is presented and collated from around the African continent to parameterize past vegetation states, identify the drivers of vegetation change, and assess the vegetation resilience to change. To achieve this research from two broad themes are covered: (i) the present is the key to the past (i.e. studies which improve our understanding of modern environments so that we can better interpret evidence from the past), and (ii) the past is the key to the future (i.e. studies which unlock information on how and why vegetation changed in the past so one can better anticipate trajectories of future change). This Open Access book will provide a strong foundation for future research exploring past ecological, environmental and climatic change within Africa and the surrounding islands. The book is organized regionally (covering western, eastern, central, and southern Africa) and it contains specialized articles focused on particular topics (such as modern pollen-vegetation relationships and fire as a driver of vegetation change), as well as regional and pan-African syntheses drawing together decades of research to assess key scientific questions (including the role of climate in driving vegetation change and the role of vegetation change in human evolution). These articles will be useful to students and teachers from high school to the highest level of university who are interested in the origins and dynamics of vegetation in Africa. Furthermore, it is also meant to provide societally relevant information that can act as an inspiration for the development of sustainable management practices for the future.

Download or read book Chemical Thermodynamics of Americium written by R.J. Silva and published by Newnes. This book was released on 2012-12-02 with total page 393 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the second volume in a series of critical reviews of the chemical thermodynamic data of those elements of particular importance in the safety assessment modeling of high-level radioactive waste storage and disposal facilities. The objective of these reviews is to provide a set of reliable thermodynamic data that can be used to describe the behaviour of these elements under conditions relevant for radioactive waste disposal systems and the geochemical environments. The present volume is a review of experimental data reported in the literature for americium. On a few occasions, where no data existed, comparisons and estimates were made based on experimental data on analog lanthanide elements. The basic philosophy was to develop a minimum set of solid phases and solution species of americium that would fit all experimental data being reviewed.

Download or read book Household Waste Recycling written by Richard Waite and published by Routledge. This book was released on 2013-11-05 with total page 195 pages. Available in PDF, EPUB and Kindle. Book excerpt: Households in the UK each generate around one tonne of waste per year, and the successful management and disposal of this waste is becoming an increasingly important issue. In many cases, recycling is the most sensible option, and the UK government has set a target to recycle a quarter of all household waste by the year 2000. This book gives an overview of the waste management and disposal options currently available, and provides a comprehensive and up-to-date analysis of how recycling could develop. The author – one of the UK's leading experts – looks at how much of the waste is potentially recyclable, shows the various ways in which recyclable materials can be separated and reprocessed, and assesses the existing markets for recyclable materials. He gives an in-depth account of the important subject of packaging recycling, and compares the UK's progress and performance with what is happening elsewhere in Europe. He also discusses how the performance of current recycling schemes can be measured and costed, and forecasts future developments in the industry. Dr Richard Waite is a former Specialist Advisor to the House of Commons Environment Select Committee and is currently a consultant with Coopers & Lybrand. He established one of the first commercial MRFs in the country, and has advised many local authorities, central government departments (including the European Commission) and private sector organisations on recycling issues. Originally published in 1995