Concise encyclopedia of semiconducting materials and related technologies

CERN Document Server

Mahajan, S M

1992-01-01

The development of electronic materials and particularly advances in semiconductor technology have played a central role in the electronics revolution by allowing the production of increasingly cheap and powerful computing equipment and advanced telecommunications devices. This Concise Encyclopedia, which incorporates relevant articles from the acclaimed Encyclopedia of Materials Science and Engineering as well as newly commissioned articles, emphasizes the materials aspects of semiconductors and the technologies important in solid-state electronics. Growth of bulk crystals and epitaxial layer

Encyclopedia of the solar system

CERN Document Server

Weissman, Paul; Johnson, Torrence

1998-01-01

The Encyclopedia of the Solar System provides a series of comprehensive and authoritative articles written by more than 50 eminent planetary and space scientists. Each chapter is self-contained yet linked by cross-references to other related chapters. This beautifully designed book is a must for the library of professional astronomers and amateur star-gazers alike, in fact for anyone who wishes to understand the nature of our solar system.Key Features* Cross-referenced throughout for easy comprehension* Superbly illustrated with over 700 photos, drawings, and diagrams, including 36 color plates* Provides 40 thematically organized chapters by more than 50 eminent contributors* Convenient glossaries of technical terms introduce each chapter* Academic Press maintains a web site for the Encyclopedia at www.academicpress.com/solar; Author-recommended web resources for additional information, images, and research developments related to each chapter of this volume, are available here

Encyclopedia of systems and control

CERN Document Server

Samad, Tariq

2015-01-01

The Encyclopedia of Systems and Control collects a broad range of short expository articles that describe the current state of the art in the central topics of control and systems engineering as well as in many of the related fields in which control is an enabling technology. The editors have assembled the most comprehensive reference possible, and this has been greatly facilitated by the publisher’s commitment continuously to publish updates to the articles as they become available in the future. Although control engineering is now a mature discipline, it remains an area in which there is a great deal of research activity, and as new developments in both theory and applications become available, they will be included in the online version of the encyclopedia. A carefully chosen team of leading authorities in the field has written the well over 200 articles that comprise the work. The topics range from basic principles of feedback in servomechanisms to advanced topics such as the control of Boolean networks...

Web-based encyclopedia on physical effects

Science.gov (United States)

Papliatseyeu, Andrey; Repich, Maryna; Ilyushonak, Boris; Hurbo, Aliaksandr; Makarava, Katerina; Lutkovski, Vladimir M.

2004-07-01

Web-based learning applications open new horizons for educators. In this work we present the computer encyclopedia designed to overcome drawbacks of traditional paper information sources such as awkward search, low update rate, limited copies count and high cost. Moreover, we intended to improve access and search functions in comparison with some Internet sources in order to make it more convenient. The system is developed using modern Java technologies (Jave Servlets, Java Server Pages) and contains systemized information about most important and explored physical effects. It also may be used in other fields of science. The system is accessible via Intranet/Internet networks by means of any up-to-date Internet browser. It may be used for general learning purposes and as a study guide or tutorial for performing laboratory works.

Encyclopedia of microfluidics and nanofluidics

CERN Document Server

2015-01-01

Covering all aspects of transport phenomena on the nano- and micro-scale, the 800 entries include 300 essay entries.  The Encyclopedia gives an up to date look at the fundamentals of the field as well as many experiments and applications in growing areas such as energy devices and bioengineering applications.

Encyclopedia of the Cold War

NARCIS (Netherlands)

van Dijk, R.

2008-01-01

Between 1945 and 1991, tension between the USA, its allies, and a group of nations led by the USSR, dominated world politics. This period was called the Cold War - a conflict that stopped short to a full-blown war. Benefiting from the recent research of newly open archives, the Encyclopedia of the

Encyclopedia of Astronomy and Astrophysics

CERN Document Server

2002-01-01

Interstellar medium, Light, Magnetisphere, Matter, Planet Earth, Public Impact, Solar Activity, Solar Heliosphere, Solar Interior, Solar Systems, Space, Stellar Astrophysics, Stellar Populations, Telescopes, Time The Encyclopedia of Astronomy and Astrophysics covers 30 major subject areas, such as Active galaxies, Astrometry, Astrophysical theory, Atmospheres, Binary stars, Biography, Clusters, Coordinates, Cosmology, Earth, Education, Galaxies,

Encyclopedia of optimization

CERN Document Server

Pardalos, Panos

2001-01-01

Optimization problems are widespread in the mathematical modeling of real world systems and their applications arise in all branches of science, applied science and engineering. The goal of the Encyclopedia of Optimization is to introduce the reader to a complete set of topics in order to show the spectrum of recent research activities and the richness of ideas in the development of theories, algorithms and the applications of optimization. It is directed to a diverse audience of students, scientists, engineers, decision makers and problem solvers in academia, business, industry, and government.

THE REACH AND RICHNESS OF WIKINOMICS: IS THE FREE WEB-BASED ENCYCLOPEDIA WIKIPEDIA ONLY FOR RICH COUNTRIES?

DEFF Research Database (Denmark)

Rask, Morten

2007-01-01

In this article, a model of the patterns of correlation in Wikipedia, reach and richness, lays the foundation for studying whether the free Web-based encyclopedia Wikipedia is only for developed countries. Based on data from 12 different Wikipedia language editions, the author finds that the cent......In this article, a model of the patterns of correlation in Wikipedia, reach and richness, lays the foundation for studying whether the free Web-based encyclopedia Wikipedia is only for developed countries. Based on data from 12 different Wikipedia language editions, the author finds...... that the central structural effect is on the level of human development in the current country. In other words, Wikipedia is in general more for rich countries than for less developed countries. It is suggested that policy makers make investments in increasing the general level of literacy, education, and standard...

Land of 10,000 Facts: Minnesota's New Digital Encyclopedia

Directory of Open Access Journals (Sweden)

Molly Huber

2014-06-01

Full Text Available Mnopedia is the recently created, born digital encyclopedia of the state of Minnesota. It is a project of the Minnesota Historical Society (MNHS, the state's leading cultural heritage institution and one of the largest and oldest historical societies in the nation. The MNHS has been in existence since 1849 and tells the story of Minnesota's past through exhibitions, extensive libraries and collections, twenty-six historic sites, educational programs, book publishing, and both financial and inkind assistance to county and local historical societies throughout the state. It provides a strong base for an encyclopedia to grow from.

Using hyperdocuments for knowledge management: an encyclopedia of southern appalachian forest ecosystems

Science.gov (United States)

Deborah K. Kennard; H. Michael Rauscher; Daniel L. Schmoldt; Patricia A. Flebbe; J.B. Jordin; W.G. Hubbard; M.C. Covington; N. Rushton

2001-01-01

Land managers increasingly need improved access to research knowledge that is thoroughly organized, condensed, and presented in a form that is useful for problem solving. In this paper, we describe the application of hyperdocuments for knowledge management, using an example of a newly developed hypertext encyclopedia on the southern Appalachians. The Encyclopedia of...

The encyclopedia of southern Appalachian forest ecosystems: A prototype of an online scientific knowledge management system

Science.gov (United States)

Deborah K. Kennard; H. Michael Rauscher; Patricia A. Flebbe; Daniel L. Schmoldt; William G. Hubbard; J. Bryan Jordin; William Milnor

2003-01-01

The Encyclopedia of Southern Appalachian Forest Ecosystems (ESAFE), a hyperdocument-based encyclopedia system available on the Internet, provides an organized synthesis of existing research on the management and ecology of Southern Appalachian forests ecosystems. The encyclopedia is dynamic, so that new or revised content can be submitted directly through the Internet...

The Transcription Factor Encyclopedia

DEFF Research Database (Denmark)

Yusuf, Dimas; Butland, Stefanie L; Swanson, Magdalena I

2012-01-01

mini review articles on pertinent human, mouse and rat TFs. Notable features of the TFe website include a high-quality PDF generator and web API for programmatic data retrieval. TFe aims to rapidly educate scientists about the TFs they encounter through the delivery of succinct summaries written......ABSTRACT: Here we present the Transcription Factor Encyclopedia (TFe), a new web-based compendium of mini review articles on transcription factors (TFs) that is founded on the principles of open access and collaboration. Our consortium of over 100 researchers has collectively contributed over 130...

Encyclopedia of Information Ethics and Security

OpenAIRE

Reviewed by Yavuz AKBULUT

2008-01-01

233Rapid developments in information andcommunication technologies have created newsecurity threats along with ethical dilemmas. Thesedevelopments have been so fast that appropriatesecurity precautions and ethical codes fail to keeppace with the technological developments. In thisrespect, education of both professionals andordinary citizens regarding information technologyethics carries utmost importance. Encyclopedia ofInformation Ethics and Security serves as anauthentic and comprehensive r...

The Concise Encyclopedia of Statistics

CERN Document Server

Dodge, Yadolah

2008-01-01

The Concise Encyclopedia of Statistics presents the essential information about statistical tests, concepts, and analytical methods in language that is accessible to practitioners and students of the vast community using statistics in medicine, engineering, physical science, life science, social science, and business/economics. The reference is alphabetically arranged to provide quick access to the fundamental tools of statistical methodology and biographies of famous statisticians. The more than 500 entries include definitions, history, mathematical details, limitations, examples, references,

CIRP encyclopedia of production engineering

CERN Document Server

Reinhart, Gunther

2014-01-01

The CIRP Encyclopedia covers the state-of-art of advanced technologies, methods and models for production, production engineering and logistics. While the technological and operational aspects are in the focus, economical aspects are adressed too. The definitions and short explanations for a wide variety of terms were reviewed by the CIRP-Community, representing the highest standards in research. Thus, the content is not only evaluated internationally on a high scientific level but also reflects very recent developments.

Islamic Context of Electronic Encyclopedias in English Language: A Critical Evaluation

Directory of Open Access Journals (Sweden)

Sajjad ur Rehman

1999-12-01

Full Text Available A systematic evaluation of Islam and Muslim world in electronic encyclopedias was conducted by using two-dimensional criteria: searching and technological capabilities, and qualitative evaluation of their content. The factors used to assess searching and technological capabilities are related to direct link, hypertext, related articles, illustration, multimedia, Boolean searching, Internet links, and search history. Content evaluation was conducted in relation to length, scope, treatment level, currency, accuracy, bias, presentation, authorship, and bibliographic documentation. The researchers identified topics that are expected to be valid indicators of the coverage and treatment of Islam and the Muslim world. Some topics are related to theological doctrines, while the others pertained to socio-historical themes. Altogether 21 topics were searched in each title. Five encyclopedias used the same terminology for certain topics, while broader or narrower terms were used for other titles. Total articles thus identified were in the range of 13 to 19. As the search was conducted for a topic, search-related data were noted. Printouts of the identified articles were obtained, and evaluated against specific criteria. It has been found that each encyclopedia has its specific strengths in regard to software and searching capabilities. In content evaluation, it was found that about 30-40% of articles in each encyclopedia had problems with regard to accuracy of information objectivity, coverage, and presentation.

Knowledge Management and Information Technology (Know-IT Encyclopedia)

National Research Council Canada - National Science Library

Pollock, Neal

2002-01-01

.... This encyclopedia is an attempt to create and distribute a knowledge-level tool. Much of it is tacit knowledge taken from the author's experience on-the-job at the Program Executive Office for Information Technology (PEO...

Macmillan Encyclopedia of Chemistry (edited by Joseph J. Lagowski)

Science.gov (United States)

Kauffman, George B.

1998-11-01

Macmillan: New York, 1997. Four volumes. Figs., tables. lxxi + 1696 pp. 22.0 x 28.5 cm. $400. ISBN 0-02-897225-2. This latest addition to Macmillan's series of comprehensive core science encyclopedias (previous sets dealt with physics and earth sciences) will be of particular interest to readers of this Journal, for it is edited by longtime Journal of Chemical Education editor Joe Lagowski, assisted by a board of five distinguished associate editors. The attractively priced set offers clear explanations of the phenomena and concepts of chemistry and its materials, whether found in industry, the laboratory, or the natural world. It is intended for a broad spectrum of readers-professionals whose work draws on chemical concepts and knowledge (e.g., material scientists, engineers, health workers, biotechnologists, mathematicians, and computer programmers), science teachers at all levels from kindergarten to high school, high school and college students interested in medicine or the sciences, college and university professors, and laypersons desiring information on practical aspects of chemistry (e.g., household cleaning products, food and food additives, manufactured materials, herbicides, the human body, sweeteners, and animal communication).

Encyclopedia of astrobiology

CERN Document Server

Irvine, William; Amils, Ricardo; Cleaves, Henderson; Pinti, Daniele; Quintanilla, José; Rouan, Daniel; Spohn, Tilman; Tirard, Stéphane; Viso, Michel

2015-01-01

The interdisciplinary field of Astrobiology constitutes a joint arena where provocative discoveries are coalescing concerning, e.g. the prevalence of exoplanets, the diversity and hardiness of life, and its increasingly likely chances for its emergence. Biologists, astrophysicists, biochemists, geoscientists and space scientists share this exciting mission of revealing the origin and commonality of life in the Universe. The members of the different disciplines are used to their own terminology and technical language. In the interdisciplinary environment many terms either have redundant meanings or are completely unfamiliar to members of other disciplines. The Encyclopedia of Astrobiology serves as the key to a common understanding. Each new or experienced researcher and graduate student in adjacent fields of astrobiology will appreciate this reference work in the quest to understand the big picture. The carefully selected group of active researchers contributing to this work and the expert field editors inten...

Encyclopedia of astrobiology

CERN Document Server

Quintanilla, José Cernicharo; Cleaves, Henderson James (Jim); Irvine, William M; Pinti, Daniele L; Viso, Michel; Gargaud, Muriel

2011-01-01

The interdisciplinary field of Astrobiology constitutes a joint arena where provocative discoveries are coalescing concerning, e.g. the prevalence of exoplanets, the diversity and hardiness of life, and its increasingly likely chances for its emergence. Biologists, astrophysicists, biochemists, geoscientists and space scientists share this exciting mission of revealing the origin and commonality of life in the Universe. The members of the different disciplines are used to their own terminology and technical language. In the interdisciplinary environment many terms either have redundant meanings or are completely unfamiliar to members of other disciplines. The Encyclopedia of Astrobiology serves as the key to a common understanding. Each new or experienced researcher and graduate student in adjacent fields of astrobiology will appreciate this reference work in the quest to understand the big picture. The carefully selected group of active researchers contributing to this work and the expert field editors inten...

An Einstein encyclopedia

CERN Document Server

Calaprice, Alice; Schulmann, Robert

2015-01-01

This is the single most complete guide to Albert Einstein’s life and work for students, researchers, and browsers alike. Written by three leading Einstein scholars who draw on their combined wealth of expertise gained during their work on the Collected Papers of Albert Einstein, this authoritative and accessible reference features more than one hundred entries and is divided into three parts covering the personal, scientific, and public spheres of Einstein’s life. An Einstein Encyclopedia contains entries on Einstein’s birth and death, family and romantic relationships, honors and awards, educational institutions where he studied and worked, citizenships and immigration to America, hobbies and travels, plus the people he befriended and the history of his archives and the Einstein Papers Project. Entries on Einstein’s scientific theories provide useful background and context, along with details about his assistants, collaborators, and rivals, as well as physics concepts related to his work. Coverage o...

Encyclopedia of biophysics

CERN Document Server

2013-01-01

The Encyclopedia of Biophysics is envisioned both as an easily accessible source of information and as an introductory guide to the scientific literature. It includes entries describing both Techniques and Systems.  In the Techniques entries, each of the wide range of methods which fall under the heading of Biophysics are explained in detail, together with the value and the limitations of the information each provides. Techniques covered range from diffraction (X-ray, electron and neutron) through a wide range of spectroscopic methods (X-ray, optical, EPR, NMR) to imaging (from electron microscopy to live cell imaging and MRI), as well as computational and simulation approaches. In the Systems entries, biophysical approaches to specific biological systems or problems – from protein and nucleic acid structure to membranes, ion channels and receptors – are described. These sections, which place emphasis on the integration of the different techniques, therefore provide an inroad into Biophysics from a biolo...

Biographical encyclopedia of astronomers

CERN Document Server

Trimble, Virginia; Williams, Thomas; Bracher, Katherine; Jarrell, Richard; Marché, Jordan; Palmeri, JoAnn; Green, Daniel

2014-01-01

The Biographical Encyclopedia of Astronomers is a unique and valuable resource for historians and astronomers alike. It includes approx. 1850 biographical sketches on astronomers from antiquity to modern times. It is the collective work of 430 authors edited by an editorial board of 8 historians and astronomers. This reference provides biographical information on astronomers and cosmologists by utilizing contemporary historical scholarship. The fully corrected and updated second edition adds approximately 300 biographical sketches. Based on ongoing research and feedback from the community, the new entries will fill gaps and provide expansions. In addition, greater emphasis on Russo phone astronomers and radio astronomers is given. Individual entries vary from 100 to 1500 words, including the likes of the super luminaries such as Newton and Einstein, as well as lesser-known astronomers like Galileo's acolyte, Mario Guiducci.

Genomic Encyclopedia of Fungi

Energy Technology Data Exchange (ETDEWEB)

Grigoriev, Igor

2012-08-10

Genomes of fungi relevant to energy and environment are in focus of the Fungal Genomic Program at the US Department of Energy Joint Genome Institute (JGI). Its key project, the Genomics Encyclopedia of Fungi, targets fungi related to plant health (symbionts, pathogens, and biocontrol agents) and biorefinery processes (cellulose degradation, sugar fermentation, industrial hosts), and explores fungal diversity by means of genome sequencing and analysis. Over 150 fungal genomes have been sequenced by JGI to date and released through MycoCosm (www.jgi.doe.gov/fungi), a fungal web-portal, which integrates sequence and functional data with genome analysis tools for user community. Sequence analysis supported by functional genomics leads to developing parts list for complex systems ranging from ecosystems of biofuel crops to biorefineries. Recent examples of such parts suggested by comparative genomics and functional analysis in these areas are presented here.

Encyclopedia of Public International Law, 6 / Henn-Jüri Uibopuu

Index Scriptorium Estoniae

Uibopuu, Henn-Jüri, 1929-2012

1984-01-01

Tutvustus: Encyclopedia of Public International Law, published under the Auspices of the Max-Planck-Institute for Comparative Public Law and International Law under the Direction of Rudolf Bernhardt. (6. regional Cooperation, Organization Problems). Amsterdam, New York, Oxford: North-Holland Publishing Company, 1983

Functional Encyclopedia of Bacteria and Archaea

Energy Technology Data Exchange (ETDEWEB)

Blow, M. J.; Deutschbauer, A. M.; Hoover, C. A.; Lamson, J.; Lamson, J.; Price, M. N.; Waters, J.; Wetmore, K. M.; Bristow, J.; Arkin, A. P.

2013-03-20

Bacteria and Archaea exhibit a huge diversity of metabolic capabilities with fundamental importance in the environment, and potential applications in biotechnology. However, the genetic bases of these capabilities remain unclear due largely to an absence of technologies that link DNA sequence to molecular function. To address this challenge, we are developing a pipeline for high throughput annotation of gene function using mutagenesis, growth assays and DNA sequencing. By applying this pipeline to annotate gene function in 50 diverse microbes we hope to discover thousands of new gene functions and produce a proof of principle `Functional Encyclopedia of Bacteria and Archaea?.

Encyclopedia of Public International Law, 2 / Henn-Jüri Uibopuu

Index Scriptorium Estoniae

Uibopuu, Henn-Jüri, 1929-2012

1982-01-01

Tutvustus: Encyclopedia of Public International Law, published under the Auspices of the Max-Planck-Institute for Comparative Public Law and International Law under the Direction of Rudolf Bernhardt. (2. Decisions of International Courts and Tribunals and International Arbitrations). Amsterdam, New York, Oxford: North-Holland Publishing Company, 1981

The richness and reach of Wikinomics: Is the free web-based encyclopedia Wikipedia only for the rich countries?

DEFF Research Database (Denmark)

Rask, Morten

2007-01-01

In this paper, a model of the patterns of correlation in Wikipedia, reach and richness, lays the foundation for studying whether or not the free web-based encyclopedia Wikipedia is only for developed countries. Based upon data from 12 different Wikipedia language editions, we find that the central...... structural effect is on the level of human development in the current country. In other words, Wikipedia is in general, more for rich countries than for less developed countries. It is suggested that policy makers make investments in increasing the general level of literacy, education, and standard of living...

Encyclopedia of Public International Law, 8 / Henn-Jüri Uibopuu

Index Scriptorium Estoniae

Uibopuu, Henn-Jüri, 1929-2012

1986-01-01

Tutvustus: Encyclopedia of Public International Law, published under the Auspices of the Max-Planck-Institute for Comparative Public Law and International Law under the Direction of Rudolf Bernhardt. (8. Human Rights and the Individual in International Law. International Economic Relations). Amsterdam, New York, Oxford: North-Holland Publishing Company, 1985

Encyclopedia of radiation oncology

Energy Technology Data Exchange (ETDEWEB)

Brady, Luther W. [Drexel Univ. College of Medicine, Philadelphia, PA (United States); Yaeger, Theodore E. (eds.) [Wake Forest Univ. School of Medicine, Winston-Salem, NC (United States). Dept. of Radiation Oncology

2013-02-01

The simple A to Z format provides easy access to relevant information in the field of radiation oncology. Extensive cross references between keywords and related articles enable efficient searches in a user-friendly manner. Fully searchable and hyperlinked electronic online edition. The aim of this comprehensive encyclopedia is to provide detailed information on radiation oncology. The wide range of entries are written by leading experts. They will provide basic and clinical scientists in academia, practice and industry with valuable information about the field of radiation oncology. Those in related fields, students, teachers, and interested laypeople will also benefit from the important and relevant information on the most recent developments. Please note that this publication is available as print only or online only or print + online set. Save 75% of the online list price when purchasing the bundle. For more information on the online version please type the publication title into the search box above, then click on the eReference version in the results list.

Dynamics of the Collateral Encyclopedia

DEFF Research Database (Denmark)

Thellefsen, Torkild Leo; Sørensen, Bent; Thellefsen, Martin Muderspach

2015-01-01

Both Umberto Eco and Charles S. Peirce have been concerned with the notion of background knowledge. Eco refers to background knowledge as the encyclopedia; Peirce’s term of reference is collateral experience. The aim of this article is to investigate the degree to which these two concepts...... are comparable. We focus on one major metaphysical issue, viz. the fact that Eco defines collateral experience, which is the first step in any process of cognition, as private, whereas Peirce, as a realist, would never accept the concept of private thoughts, feelings, etc. We suggest that freeing collateral...... experience from its nominalistic nomenclature makes possible a comparison and synthesis of Eco’s and Peirce’s conceptions when seen from the perspectives of their cognitive type, nuclear type, and molar content....

Encyclopedia of Public International Law, 3 / Henn-Jüri Uibopuu

Index Scriptorium Estoniae

Uibopuu, Henn-Jüri, 1929-2012

1983-01-01

Tutvustus.: Encyclopedia of Public International Law, published under the Auspices of the Max-Planck-Institute for Comparative Public Law and International Law under the Direction of Rudolf Bernhardt. 3 (A_M) and 4 (N-Z): Use of Force. War and Neutrality. Peace treaties. Amsterdam, New York, Oxford: North-Holland Publishing Company, 1982

Encyclopedia of Public International Law, 7 / Henn-Jüri Uibopuu

Index Scriptorium Estoniae

Uibopuu, Henn-Jüri, 1929-2012

1985-01-01

Tutvustus.: Encyclopedia of Public International Law, published under the Auspices of the Max-Planck-Institute for Comparative Public Law and International Law under the Direction of Rudolf Bernhardt. (7. History of International Law. Foundations and Principles of International Law. Sources of International Law. Law of Treaties). Amsterdam, New York, Oxford: North-Holland Publishing Company, 1984

Encyclopedia of diagnostic imaging

International Nuclear Information System (INIS)

Baert, A.L.

2008-01-01

The simple A to Z format provides easy access to relevant information in the field of imaging. Extensive cross references between keywords and related articles enable efficient searches in a user-friendly manner. Fully searchable and hyperlinked electronic online edition. The aim of this comprehensive encyclopedia is to provide detailed information on diagnostic radiology contributing to the broad field of imaging. The wide range of entries are written by leading experts. They will provide basic and clinical scientists in academia, practice and industry with valuable information about the field of diagnostic imaging. Those in related fields, students, teachers, and interested laypeople will also benefit from the important and relevant information on the most recent developments. Please note that this publication is available as print only or online only or print + online set. Save 75% of the online list price when purchasing the bundle. For more information on the online version please type the publication title into the search box above, then click on the eReference version in the results list. (orig.)

Chemical Speciation - General Information

Science.gov (United States)

This page includes general information about the Chemical Speciation Network that is not covered on the main page. Commonly visited documents, including calendars, site lists, and historical files for the program are listed here

Encyclopedia of Complexity and Systems Science

CERN Document Server

Meyers, Robert A

2009-01-01

Encyclopedia of Complexity and Systems Science provides an authoritative single source for understanding and applying the concepts of complexity theory together with the tools and measures for analyzing complex systems in all fields of science and engineering. The science and tools of complexity and systems science include theories of self-organization, complex systems, synergetics, dynamical systems, turbulence, catastrophes, instabilities, nonlinearity, stochastic processes, chaos, neural networks, cellular automata, adaptive systems, and genetic algorithms. Examples of near-term problems and major unknowns that can be approached through complexity and systems science include: The structure, history and future of the universe; the biological basis of consciousness; the integration of genomics, proteomics and bioinformatics as systems biology; human longevity limits; the limits of computing; sustainability of life on earth; predictability, dynamics and extent of earthquakes, hurricanes, tsunamis, and other n...

Digging Wikipedia : The Online Encyclopedia as a Digital Cultural Heritage Gateway and Site

NARCIS (Netherlands)

Pentzold, C.; Weltevrede, E.; Mauri, M.; Laniado, D.; Kaltenbrunner, A.; Borra, E.

The online encyclopedia Wikipedia is both a cultural reference to store, refer to, and organize digitized and digital information, as well as a key contemporary digital heritage endeavor in itself. Capitalizing on this dual nature of the project, this article introduces Wikipedia as a digital

Encyclopedia of color science and technology

CERN Document Server

2016-01-01

The Encyclopedia of Color Science and Technology provides an authoritative single source for understanding and applying the concepts of color to all fields of science and technology, including artistic and historical aspects of color. Many topics are discussed in this timely reference, including an introduction to the science of color, and entries on the physics, chemistry and perception of color. Color is described as it relates to optical phenomena of color and continues on through colorants and materials used to modulate color and also to human vision of color. The measurement of color is provided as is colorimetry, color spaces, color difference metrics, color appearance models, color order systems and cognitive color. Other topics discussed include industrial color, color imaging, capturing color, displaying color and printing color. Descriptions of color encodings, color management, processing color and applications relating to color synthesis for computer graphics are included in this work. The Encyclo...

Design of Application Software : Visualization of Electronic Encyclopedia with Multimedia Basis

International Nuclear Information System (INIS)

Laggoune, Hayet; Madenda, Sarifuddin; Gunawan, Teddy

2001-01-01

This paper discusses a multimedia program which visualizes an electronic dictionary / encyclopedia. This program uses different types of files such as text, sound, graphic and video. These files are related to each corresponding word as defined in the dictionary. This software is easy to use and allow searching, adding, editing or deleting data from the dictionary. It can also visualizes the word contain as text, graphic, sound or video

Using a digital marketing platform for the promotion of an internet based health encyclopedia in saudi arabia.

Science.gov (United States)

Al Ateeq, Asma; Al Moamary, Eman; Daghestani, Tahani; Al Muallem, Yahya; Al Dogether, Majed; Alsughayr, Abdulrahman; Altuwaijri, Majid; Househ, Mowafa

2015-01-01

The objective of this paper is to investigate the experiences of using a digital marketing platform to promote the use of an internet based health encyclopedia in Saudi Arabia. Key informant interviews, meeting documentation, and Google Analytics were the data collection sources used in the study. Findings show that using a digital marketing platform led to a significant increase in the number of visitors to the health encyclopedia. The results demonstrate that digital marketing platforms are effective tools to be used for promoting internet based health education interventions. Future work will examine long-term educational impacts and costs in using digital marketing platforms to promote online healthcare sites in Saudi Arabia.

Wikipedias: Collaborative web-based encyclopedias as complex networks

Science.gov (United States)

Zlatić, V.; Božičević, M.; Štefančić, H.; Domazet, M.

2006-07-01

Wikipedia is a popular web-based encyclopedia edited freely and collaboratively by its users. In this paper we present an analysis of Wikipedias in several languages as complex networks. The hyperlinks pointing from one Wikipedia article to another are treated as directed links while the articles represent the nodes of the network. We show that many network characteristics are common to different language versions of Wikipedia, such as their degree distributions, growth, topology, reciprocity, clustering, assortativity, path lengths, and triad significance profiles. These regularities, found in the ensemble of Wikipedias in different languages and of different sizes, point to the existence of a unique growth process. We also compare Wikipedias to other previously studied networks.

Genetics Home Reference: congenital generalized lipodystrophy

Science.gov (United States)

... an abnormal buildup of fats in the liver (hepatic steatosis), which can result in an enlarged liver (hepatomegaly) ... links) Encyclopedia: Acanthosis Nigricans Encyclopedia: Chronic ... Hypertrophic Cardiomypathy Encyclopedia: Polycystic Ovary Syndrome ...

Kaspar Schott's "encyclopedia of all mathematical sciences"

Science.gov (United States)

Knobloch, Eberhard

2011-06-01

In 1661, Kaspar Schott published his comprehensive textbook "Cursus mathematicus" in Würzburg for the first time, his "Encyclopedia of all mathematical sciences". It was so successful that it was published again in 1674 and 1677. In its 28 books, Schott gave an introduction for beginners in 22 mathematical disciplines by means of 533 figures and numerous tables. He wanted to avoid the shortness and the unintelligibility of his predecessors Alsted and Hérigone. He cited or recommended far more than hundred authors, among them Protestants like Michael Stifel and Johannes Kepler, but also Catholics like Nicolaus Copernicus. The paper gives a survey of this work and explains especially interesting aspects: The dedication to the German emperor Leopold I., Athanasius Kircher's letter of recommendation as well as Schott's classification of sciences, explanations regarding geometry, astronomy, and algebra.

The library without walls: images, medical dictionaries, atlases, medical encyclopedias free on web.

Science.gov (United States)

Giglia, E

2008-09-01

The aim of this article was to present the ''reference room'' of the Internet, a real library without walls. The reader will find medical encyclopedias, dictionaries, atlases, e-books, images, and will also learn something useful about the use and reuse of images in a text and in a web site, according to the copyright law.

Encyclopedia of cosmology historical, philosophical, and scientific foundations of modern cosmology

CERN Document Server

Hetherington, Norriss S

2014-01-01

The Encyclopedia of Cosmology, first published in 1993, recounts the history, philosophical assumptions, methodological ambiguities, and human struggles that have influenced the various responses to the basic questions of cosmology through the ages, as well as referencing important scientific theories.Just as the recognition of social conventions in other cultures can lead to a more productive perspective on our own behaviour, so too a study of the cosmologies of other times and places can enable us recognise elements of our own cosmology that might otherwise pass as inevitable developments.Ap

General approaches to the risk assessment of chemicals

Energy Technology Data Exchange (ETDEWEB)

Murphy, Patrick [Commission of the European Communities, Directorate General XI, Environment, Nuclear Safety and Civil Protection (Belgium)

1992-07-01

In the context of the UNCED 92 'Earth Summit' in Rio, the following definition of chemical risk assessment has been developed: 'Chemical risk assessment is a scientific process that identifies and quantifies the potential adverse effects on human health or ecosystems of defined exposures to chemical substances, to mixtures that include chemicals, or to chemically hazardous processes or situations. Risk itself is the probability of the occurrence of a defined adverse effect in a defined group and in defined circumstances'. I would not be so impertinent as to try and improve upon a definition that has the tacit endorsement of the majority of world-leaders. Furthermore, I consider that too many man-years have been spent discussing this topic. Thankfully the UNCED definition recognises chemical risk assessment as being a process and not some immutable physical law. In this presentation I will attempt to explain some of the details and mechanisms of that process but first of all it is worthwhile to spend a few moments putting chemical risk assessment in its proper context and asking the simple question: why do we want/need to assess the potential risk of chemicals?. In general terms, chemicals risk assessment is carried out in order to ensure that neither man (consumer/worker/general public) nor the environment are exposed to unacceptable risks arising from the production, use and disposal of chemicals. At a national and/or international level, risk assessments are performed by the regulatory authorities before they accept notification dossiers (e.g. new industrial chemicals) or grant authorizations (e.g. pharmaceuticals, pesticides, cosmetics, food additives). At the local level, plant-operators must carry out risk assessments to ensure that in the particular circumstances of their factory the workers are adequately protected and that satisfactory accident prevention and contingency plans are prepared. Similarly, local authorities must carry out risk assessments before

General approaches to the risk assessment of chemicals

International Nuclear Information System (INIS)

Murphy, Patrick

1992-01-01

In the context of the UNCED 92 'Earth Summit' in Rio, the following definition of chemical risk assessment has been developed: 'Chemical risk assessment is a scientific process that identifies and quantifies the potential adverse effects on human health or ecosystems of defined exposures to chemical substances, to mixtures that include chemicals, or to chemically hazardous processes or situations. Risk itself is the probability of the occurrence of a defined adverse effect in a defined group and in defined circumstances'. I would not be so impertinent as to try and improve upon a definition that has the tacit endorsement of the majority of world-leaders. Furthermore, I consider that too many man-years have been spent discussing this topic. Thankfully the UNCED definition recognises chemical risk assessment as being a process and not some immutable physical law. In this presentation I will attempt to explain some of the details and mechanisms of that process but first of all it is worthwhile to spend a few moments putting chemical risk assessment in its proper context and asking the simple question: why do we want/need to assess the potential risk of chemicals?. In general terms, chemicals risk assessment is carried out in order to ensure that neither man (consumer/worker/general public) nor the environment are exposed to unacceptable risks arising from the production, use and disposal of chemicals. At a national and/or international level, risk assessments are performed by the regulatory authorities before they accept notification dossiers (e.g. new industrial chemicals) or grant authorizations (e.g. pharmaceuticals, pesticides, cosmetics, food additives). At the local level, plant-operators must carry out risk assessments to ensure that in the particular circumstances of their factory the workers are adequately protected and that satisfactory accident prevention and contingency plans are prepared. Similarly, local authorities must carry out risk assessments before

[Vladimir Zederbaum" (1883-1942): Physician, journalist, contributor to the Russian "Jewish, Encyclopedia". A research report].

Science.gov (United States)

Antipova, Anastasia

2015-01-01

Vol. 15 o f the "Jewish Encyclopedia" (St. Petersburg 1908-1913) contains an article on Freud, signed by Vladimir Zederbaum. The data for the article were provided by Max Eitingon. This paper addresses the question of whether Zederbaum himself was Eitingon's contact. Several archives produced a lot of information about Zederbaum's medical and journalistic activities in St. Petersburg. However, to date no connection between the two men could be established.

The Japanese Nuclear Energy Encyclopedia edited and computerized to promote public acceptance

International Nuclear Information System (INIS)

Shimooke, T.; Kobayashi, K.; Suzuki, Y.; Kobayashi, S.

1992-01-01

Editing the Japanese Nuclear Energy Encyclopedia has been in progress since 1989. It will be completed in 1993. The book is intended to provide raw material for the public to have his own judgement on nuclear energy. It is also useful as a 'text book' for specialists who lecture on the nuclear energy including the social effects at public seminars and meetings. Computerization of the book is also being made simultaneously. The trial use of the partly completed book has been started by some 150 of the nominated lectures through the country from August 1992. The computerized book has been well received so far by these lectures. (J.P.N.)

Diabatic models with transferrable parameters for generalized chemical reactions

International Nuclear Information System (INIS)

Reimers, Jeffrey R; McKemmish, Laura K; McKenzie, Ross H; Hush, Noel S

2017-01-01

Diabatic models applied to adiabatic electron-transfer theory yield many equations involving just a few parameters that connect ground-state geometries and vibration frequencies to excited-state transition energies and vibration frequencies to the rate constants for electron-transfer reactions, utilizing properties of the conical-intersection seam linking the ground and excited states through the Pseudo Jahn-Teller effect. We review how such simplicity in basic understanding can also be obtained for general chemical reactions. The key feature that must be recognized is that electron-transfer (or hole transfer) processes typically involve one electron (hole) moving between two orbitals, whereas general reactions typically involve two electrons or even four electrons for processes in aromatic molecules. Each additional moving electron leads to new high-energy but interrelated conical-intersection seams that distort the shape of the critical lowest-energy seam. Recognizing this feature shows how conical-intersection descriptors can be transferred between systems, and how general chemical reactions can be compared using the same set of simple parameters. Mathematical relationships are presented depicting how different conical-intersection seams relate to each other, showing that complex problems can be reduced into an effective interaction between the ground-state and a critical excited state to provide the first semi-quantitative implementation of Shaik’s “twin state” concept. Applications are made (i) demonstrating why the chemistry of the first-row elements is qualitatively so different to that of the second and later rows, (ii) deducing the bond-length alternation in hypothetical cyclohexatriene from the observed UV spectroscopy of benzene, (iii) demonstrating that commonly used procedures for modelling surface hopping based on inclusion of only the first-derivative correction to the Born-Oppenheimer approximation are valid in no region of the chemical

The Mysterious Case of the Detective as Child Hero: Sherlock Holmes, Encyclopedia Brown and Nancy Drew as Role Models?

Science.gov (United States)

Sugarman, Sally

In the mystery genre, the one characteristic that the enduring figures of Sherlock Holmes, Nancy Drew, and Encyclopedia Brown have in common is a rational mind. The source of their strength is their ability to think and think well. A study examined some typical examples of the mystery genre in young adult literature and surveyed children and…

Exploring Chemical Equilibrium with Poker Chips: A General Chemistry Laboratory Exercise

Science.gov (United States)

Bindel, Thomas H.

2012-01-01

A hands-on laboratory exercise at the general chemistry level introduces students to chemical equilibrium through a simulation that uses poker chips and rate equations. More specifically, the exercise allows students to explore reaction tables, dynamic chemical equilibrium, equilibrium constant expressions, and the equilibrium constant based on…

Endocrine Disruptor Screening Program (EDSP) Universe of Chemicals and General Validation Principles

Science.gov (United States)

This document was developed by the EPA to provide guidance to staff and managers regarding the EDSP universe of chemicals and general validation principles for consideration of computational toxicology tools for chemical prioritization.

A Computer Algebra Approach to Solving Chemical Equilibria in General Chemistry

Science.gov (United States)

Kalainoff, Melinda; Lachance, Russ; Riegner, Dawn; Biaglow, Andrew

2012-01-01

In this article, we report on a semester-long study of the incorporation into our general chemistry course, of advanced algebraic and computer algebra techniques for solving chemical equilibrium problems. The method presented here is an alternative to the commonly used concentration table method for describing chemical equilibria in general…

Building large collections of Chinese and English medical terms from semi-structured and encyclopedia websites.

Science.gov (United States)

Xu, Yan; Wang, Yining; Sun, Jian-Tao; Zhang, Jianwen; Tsujii, Junichi; Chang, Eric

2013-01-01

To build large collections of medical terms from semi-structured information sources (e.g. tables, lists, etc.) and encyclopedia sites on the web. The terms are classified into the three semantic categories, Medical Problems, Medications, and Medical Tests, which were used in i2b2 challenge tasks. We developed two systems, one for Chinese and another for English terms. The two systems share the same methodology and use the same software with minimum language dependent parts. We produced large collections of terms by exploiting billions of semi-structured information sources and encyclopedia sites on the Web. The standard performance metric of recall (R) is extended to three different types of Recall to take the surface variability of terms into consideration. They are Surface Recall (R(S)), Object Recall (R(O)), and Surface Head recall (R(H)). We use two test sets for Chinese. For English, we use a collection of terms in the 2010 i2b2 text. Two collections of terms, one for English and the other for Chinese, have been created. The terms in these collections are classified as either of Medical Problems, Medications, or Medical Tests in the i2b2 challenge tasks. The English collection contains 49,249 (Problems), 89,591 (Medications) and 25,107 (Tests) terms, while the Chinese one contains 66,780 (Problems), 101,025 (Medications), and 15,032 (Tests) terms. The proposed method of constructing a large collection of medical terms is both efficient and effective, and, most of all, independent of language. The collections will be made publicly available.

USING MULTIMEDIA AND WEB TECHNOLOGIES IN STUDYING THE HUMANITIES. WEB-MULTIMEDIA ENCYCLOPEDIA «WILLIAM SHAKESPEARE AND RENAISSANCE».

Directory of Open Access Journals (Sweden)

E. Alferov

2010-06-01

Full Text Available The article discusses the use of innovative information technologies in modern education. Special attention is given to the using of web-multimedia technologies in the study of humanities. As an example of using information and communication tools in the process of philological disciplines described purpose, functionality and architecture of web-multimedia encyclopedia «William Shakespeare and Renaissance» (http://shakespeare.ksu.ks.ua, developed in laboratory of the integrated learning environments of the Research Institute of IT.

Modeling of chemical exergy of agricultural biomass using improved general regression neural network

International Nuclear Information System (INIS)

Huang, Y.W.; Chen, M.Q.; Li, Y.; Guo, J.

2016-01-01

A comprehensive evaluation for energy potential contained in agricultural biomass was a vital step for energy utilization of agricultural biomass. The chemical exergy of typical agricultural biomass was evaluated based on the second law of thermodynamics. The chemical exergy was significantly influenced by C and O elements rather than H element. The standard entropy of the samples also was examined based on their element compositions. Two predicted models of the chemical exergy were developed, which referred to a general regression neural network model based upon the element composition, and a linear model based upon the high heat value. An auto-refinement algorithm was firstly developed to improve the performance of regression neural network model. The developed general regression neural network model with K-fold cross-validation had a better ability for predicting the chemical exergy than the linear model, which had lower predicted errors (±1.5%). - Highlights: • Chemical exergies of agricultural biomass were evaluated based upon fifty samples. • Values for the standard entropy of agricultural biomass samples were calculated. • A linear relationship between chemical exergy and HHV of samples was detected. • An improved GRNN prediction model for the chemical exergy of biomass was developed.

CONFIGURATIONS OF THE ENCYCLOPEDIA AND THE MODEL READER IN A TEXTBOOK OF MISIONES, ARGENTINA / CONFIGURACIONES DE LA ENCICLOPEDIA Y EL LECTOR MODELO EN UN TEXTO ESCOLAR DE MISIONES, ARGENTINA

Directory of Open Access Journals (Sweden)

Froilán Fernández

2013-07-01

Full Text Available This paper attempts to analyze, from the conceptual categories of Encyclopedia and Model Reader raised by Umberto Eco, a fragment of the school handbook Misiones 4, text required reading during the last two decades in schools in the State of Misiones, Argentina. The hypothesis to guide our analysis consider that the text fragment -but also the entire textbook Misiones 4- reinforces and configures an encyclopedia "official" that promotes the historical continuity -forgetting conflicts and tensions- between the Jesuit province of 18th century and the Argentine state of 20th century, postulating, at the same, a Reader Model that adheres to a simplified pedagogical and religious local memory.

Logic from A to Z the Routledge encyclopedia of philosophy glossary of logical and mathematical terms

CERN Document Server

Bacon, John B; McCarty, David Charles; Bacon, John B

1999-01-01

First published in the most ambitious international philosophy project for a generation; the Routledge Encyclopedia of Philosophy. Logic from A to Z is a unique glossary of terms used in formal logic and the philosophy of mathematics. Over 500 entries include key terms found in the study of: * Logic: Argument, Turing Machine, Variable * Set and model theory: Isomorphism, Function * Computability theory: Algorithm, Turing Machine * Plus a table of logical symbols. Extensively cross-referenced to help comprehension and add detail, Logic from A to Z provides an indispensable reference source for students of all branches of logic.

How Readers Shape the Content of an Encyclopedia: A Case Study Comparing the German Meyers Konversationslexikon (1885-1890 with Wikipedia (2002-2013

Directory of Open Access Journals (Sweden)

Ulrike Spree

2014-06-01

Full Text Available How knowledge is negotiated between the makers of encyclopedias and their audiences remains an ongoing question in research on encyclopedias. A comparative content analysis of the published answers of letters to the editor of the German Meyers Konversationslexikon (Korrespondenzblatt from 1885 and the discussion pages of the article potato of the German Wikipedia (2013 reveals continuities as well as changes in the communication between encyclopedia producers and their audiences. The main reasons why readers and editors communicate are the need for updated factual information, an exchange on editorial principles and the intellectual exchange of ideas on ideological and philosophical questions in relation to the encyclopedic content. Editors and readers attach a lot of importance to the process of verifying information through bibliographical references. Whereas, for the editors of Meyers Konversationslexikon the leading role of experts remains undisputed, Wikipedians work in a contradictory situation. They are on the one hand exposing knowledge production to a permanent process of negotiation, thereby challenging the role of experts, on the other hand relying strongly on bibliographical authorities. Whilst the reasons for the communication between readers and editors of Meyers Konversationslexikon and among Wikipedia contributors coincide, the understanding of the roles of readers and editors differ. The editors of the Korrespondenzblatt keep up a lecturing attitude. As opposed to this, administrators in Wikipedia want to encourage participation and strive to develop expertise among the participating contributors. Albeit power relations between administrators, regular authors, occasional authors and readers continue to exist they are comparatively flat and transient. Regardless of these differences, the comparison between Meyers Konversationslexikon and Wikipedia indicates that the sine qua non for activating an upwards spiral of quality

General extrapolation model for an important chemical dose-rate effect

International Nuclear Information System (INIS)

Gillen, K.T.; Clough, R.L.

1984-12-01

In order to extrapolate material accelerated aging data, methodologies must be developed based on sufficient understanding of the processes leading to material degradation. One of the most important mechanisms leading to chemical dose-rate effects in polymers involves the breakdown of intermediate hydroperoxide species. A general model for this mechanism is derived based on the underlying chemical steps. The results lead to a general formalism for understanding dose rate and sequential aging effects when hydroperoxide breakdown is important. We apply the model to combined radiation/temperature aging data for a PVC material and show that this data is consistent with the model and that model extrapolations are in excellent agreement with 12-year real-time aging results from an actual nuclear plant. This model and other techniques discussed in this report can aid in the selection of appropriate accelerated aging methods and can also be used to compare and select materials for use in safety-related components. This will result in increased assurance that equipment qualification procedures are adequate

Earth System Monitoring Selected Entries from the Encyclopedia of Sustainability Science and Technology

CERN Document Server

2013-01-01

Modern Earth System Monitoring represents a fundamental change in the way scientists study the Earth System.  In Oceanography, for the past two centuries, ships have provided the platforms for observing.  Expeditions on the continents and Earth’s poles are land-based analogues. Fundamental understanding of current systems, climate, natural hazards, and ecosystems has been greatly advanced. While these approaches have been remarkably successful, the need to establish measurements over time can only be made using Earth observations and observatories with exacting standards and continuous data.  The 19 peer-reviewed contributions in this volume provide early insights into this emerging view of Earth in both space and time in which change is a critical component of our growing understanding. Presents 19 authoritative, peer-reviewed entries from the Encyclopedia of Sustainability Science and Technology Covers a wide range of data collection platforms, including satellite remote sensing, aerial surveys, and l...

Measurement standards and the general problem of reference points in chemical analysis

International Nuclear Information System (INIS)

Richter, W.; Dube, G.

2002-01-01

Besides the measurement standards available in general metrology in the form of the realisations of the units of measurement, measurement standards of chemical composition are needed for the vast field of chemical measurement (measurements of the chemical composition), because it is the main aim of such measurements to quantify non-isolated substances, often in complicated matrices, to which the 'classical' measurement standards and their lower- level derivatives are not directly applicable. At present, material artefacts as well as standard measurement devices serve as chemical measurement standards. These are measurement standards in the full metrological sense only, however, if they are firmly linked to the SI unit in which the composition represented by the standard is expressed. This requirement has the consequence that only a very restricted number of really reliable chemical measurement standards exist at present. Since it is very difficult and time consuming to increase this number substantially and, on the other hand, reliable reference points are increasingly needed for all kinds of chemical measurements, primary methods of measurement and high-level reference measurements will play an increasingly important role for the establishment of worldwide comparability and hence mutual acceptance of chemical measurement results. (author)

Supra-molecular structure and chemical reactivity of cellulose I studied using CP/MAS (sup)13 C-NMR

CSIR Research Space (South Africa)

Chunilall, Viren

2013-08-01

Full Text Available There are a few traditional methods of analysing the chemical properties of cellulose I. Some of these methods include the Permanganate number determination, which is used to obtain the lignin content of the pulp [12]. The acid insoluble lignin content... – Fundamental Aspects 88 [10] Fengel D, Wegener G. Wood Chemistry, Ultrastructure, Reactions, Walter de Gruyter; 1984. [11] Uhlmann T. Ullmann's encyclopedia of industrial chemistry. Paper and Pulp. 1991; 18 (A). [12] Permanganate number of pulp, Tappi T...

Some Matrix Iterations for Computing Generalized Inverses and Balancing Chemical Equations

Directory of Open Access Journals (Sweden)

Farahnaz Soleimani

2015-11-01

Full Text Available An application of iterative methods for computing the Moore–Penrose inverse in balancing chemical equations is considered. With the aim to illustrate proposed algorithms, an improved high order hyper-power matrix iterative method for computing generalized inverses is introduced and applied. The improvements of the hyper-power iterative scheme are based on its proper factorization, as well as on the possibility to accelerate the iterations in the initial phase of the convergence. Although the effectiveness of our approach is confirmed on the basis of the theoretical point of view, some numerical comparisons in balancing chemical equations, as well as on randomly-generated matrices are furnished.

Genetics Home Reference: Emanuel syndrome

Science.gov (United States)

... of Emanuel syndrome include an unusually small head ( microcephaly ), distinctive facial features, and a small lower jaw ( ... MedlinePlus Encyclopedia: Cleft Lip and Palate MedlinePlus Encyclopedia: Microcephaly MedlinePlus Encyclopedia: Preauricular Tag or Pit General Information ...

General constraints on the effect of gas flows in the chemical evolution of galaxies

International Nuclear Information System (INIS)

Edmunds, M.G.

1990-01-01

The basic equations for the chemical evolution of galaxies in which the 'simple' closed box model is modified to allow any form of inflow or outflow are examined. It is found that there are quite general limiting constraints on the effects that such flows can have. Some implications for the actual chemical evolution of galaxies are discussed, and the constraints should also be useful in understanding the behaviour of detailed numerical models of galactic chemical evolution involving gas flows. (author)

Genomics Encyclopedia of Bacteria and Archaea-Root Nodule Bacteria (GEBA-RNB): a resource for microsymbiont genomes (2013 DOE JGI Genomics of Energy and Environment 8th Annual User Meeting)

Energy Technology Data Exchange (ETDEWEB)

Reeve, Wayne [Murdoch University

2013-03-01

Wayne Reeve of Murdoch University on "Genomics Encyclopedia of Bacteria and Archaea-Root Nodule Bacteria (GEBA-RNB): a resource for microsymbiont genomes" at the 8th Annual Genomics of Energy & Environment Meeting on March 27, 2013 in Walnut Creek, Calif.

The Cancer Cell Line Encyclopedia enables predictive modelling of anticancer drug sensitivity.

Science.gov (United States)

Barretina, Jordi; Caponigro, Giordano; Stransky, Nicolas; Venkatesan, Kavitha; Margolin, Adam A; Kim, Sungjoon; Wilson, Christopher J; Lehár, Joseph; Kryukov, Gregory V; Sonkin, Dmitriy; Reddy, Anupama; Liu, Manway; Murray, Lauren; Berger, Michael F; Monahan, John E; Morais, Paula; Meltzer, Jodi; Korejwa, Adam; Jané-Valbuena, Judit; Mapa, Felipa A; Thibault, Joseph; Bric-Furlong, Eva; Raman, Pichai; Shipway, Aaron; Engels, Ingo H; Cheng, Jill; Yu, Guoying K; Yu, Jianjun; Aspesi, Peter; de Silva, Melanie; Jagtap, Kalpana; Jones, Michael D; Wang, Li; Hatton, Charles; Palescandolo, Emanuele; Gupta, Supriya; Mahan, Scott; Sougnez, Carrie; Onofrio, Robert C; Liefeld, Ted; MacConaill, Laura; Winckler, Wendy; Reich, Michael; Li, Nanxin; Mesirov, Jill P; Gabriel, Stacey B; Getz, Gad; Ardlie, Kristin; Chan, Vivien; Myer, Vic E; Weber, Barbara L; Porter, Jeff; Warmuth, Markus; Finan, Peter; Harris, Jennifer L; Meyerson, Matthew; Golub, Todd R; Morrissey, Michael P; Sellers, William R; Schlegel, Robert; Garraway, Levi A

2012-03-28

The systematic translation of cancer genomic data into knowledge of tumour biology and therapeutic possibilities remains challenging. Such efforts should be greatly aided by robust preclinical model systems that reflect the genomic diversity of human cancers and for which detailed genetic and pharmacological annotation is available. Here we describe the Cancer Cell Line Encyclopedia (CCLE): a compilation of gene expression, chromosomal copy number and massively parallel sequencing data from 947 human cancer cell lines. When coupled with pharmacological profiles for 24 anticancer drugs across 479 of the cell lines, this collection allowed identification of genetic, lineage, and gene-expression-based predictors of drug sensitivity. In addition to known predictors, we found that plasma cell lineage correlated with sensitivity to IGF1 receptor inhibitors; AHR expression was associated with MEK inhibitor efficacy in NRAS-mutant lines; and SLFN11 expression predicted sensitivity to topoisomerase inhibitors. Together, our results indicate that large, annotated cell-line collections may help to enable preclinical stratification schemata for anticancer agents. The generation of genetic predictions of drug response in the preclinical setting and their incorporation into cancer clinical trial design could speed the emergence of 'personalized' therapeutic regimens.

The Cancer Cell Line Encyclopedia enables predictive modeling of anticancer drug sensitivity

Science.gov (United States)

Barretina, Jordi; Caponigro, Giordano; Stransky, Nicolas; Venkatesan, Kavitha; Margolin, Adam A.; Kim, Sungjoon; Wilson, Christopher J.; Lehár, Joseph; Kryukov, Gregory V.; Sonkin, Dmitriy; Reddy, Anupama; Liu, Manway; Murray, Lauren; Berger, Michael F.; Monahan, John E.; Morais, Paula; Meltzer, Jodi; Korejwa, Adam; Jané-Valbuena, Judit; Mapa, Felipa A.; Thibault, Joseph; Bric-Furlong, Eva; Raman, Pichai; Shipway, Aaron; Engels, Ingo H.; Cheng, Jill; Yu, Guoying K.; Yu, Jianjun; Aspesi, Peter; de Silva, Melanie; Jagtap, Kalpana; Jones, Michael D.; Wang, Li; Hatton, Charles; Palescandolo, Emanuele; Gupta, Supriya; Mahan, Scott; Sougnez, Carrie; Onofrio, Robert C.; Liefeld, Ted; MacConaill, Laura; Winckler, Wendy; Reich, Michael; Li, Nanxin; Mesirov, Jill P.; Gabriel, Stacey B.; Getz, Gad; Ardlie, Kristin; Chan, Vivien; Myer, Vic E.; Weber, Barbara L.; Porter, Jeff; Warmuth, Markus; Finan, Peter; Harris, Jennifer L.; Meyerson, Matthew; Golub, Todd R.; Morrissey, Michael P.; Sellers, William R.; Schlegel, Robert; Garraway, Levi A.

2012-01-01

The systematic translation of cancer genomic data into knowledge of tumor biology and therapeutic avenues remains challenging. Such efforts should be greatly aided by robust preclinical model systems that reflect the genomic diversity of human cancers and for which detailed genetic and pharmacologic annotation is available1. Here we describe the Cancer Cell Line Encyclopedia (CCLE): a compilation of gene expression, chromosomal copy number, and massively parallel sequencing data from 947 human cancer cell lines. When coupled with pharmacologic profiles for 24 anticancer drugs across 479 of the lines, this collection allowed identification of genetic, lineage, and gene expression-based predictors of drug sensitivity. In addition to known predictors, we found that plasma cell lineage correlated with sensitivity to IGF1 receptor inhibitors; AHR expression was associated with MEK inhibitor efficacy in NRAS-mutant lines; and SLFN11 expression predicted sensitivity to topoisomerase inhibitors. Altogether, our results suggest that large, annotated cell line collections may help to enable preclinical stratification schemata for anticancer agents. The generation of genetic predictions of drug response in the preclinical setting and their incorporation into cancer clinical trial design could speed the emergence of “personalized” therapeutic regimens2. PMID:22460905

Climate Change Modeling Methodology Selected Entries from the Encyclopedia of Sustainability Science and Technology

CERN Document Server

2012-01-01

The Earth's average temperature has risen by 1.4°F over the past century, and computer models project that it will rise much more over the next hundred years, with significant impacts on weather, climate, and human society. Many climate scientists attribute these increases to the buildup of greenhouse gases produced by the burning of fossil fuels and to the anthropogenic production of short-lived climate pollutants. Climate Change Modeling Methodologies: Selected Entries from the Encyclopedia of Sustainability Science and Technology provides readers with an introduction to the tools and analysis techniques used by climate change scientists to interpret the role of these forcing agents on climate.  Readers will also gain a deeper understanding of the strengths and weaknesses of these models and how to test and assess them.  The contributions include a glossary of key terms and a concise definition of the subject for each topic, as well as recommendations for sources of more detailed information. Features au...

Encyclopedia of distances

CERN Document Server

Deza, Michel Marie

2016-01-01

This 4th edition of the leading reference volume on distance metrics is characterized by updated and rewritten sections on some items suggested by experts and readers, as well a general streamlining of content and the addition of essential new topics. Though the structure remains unchanged, the new edition also explores recent advances in the use of distances and metrics for e.g. generalized distances, probability theory, graph theory, coding theory, data analysis. New topics in the purely mathematical sections include e.g. the Vitanyi multiset-metric, algebraic point-conic distance, triangular ratio metric, Rossi-Hamming metric, Taneja distance, spectral semimetric between graphs, channel metrization, and Maryland bridge distance. The multidisciplinary sections have also been supplemented with new topics, including: dynamic time wrapping distance, memory distance, allometry, atmospheric depth, elliptic orbit distance, VLBI distance measurements, the astronomical system of units, and walkability distance. Lea...

Geoengineering Responses to Climate Change Selected Entries from the Encyclopedia of Sustainability Science and Technology

CERN Document Server

Vaughan, Naomi

2013-01-01

Failure by the international community to make substantive progress in reducing CO2 emissions, coupled with recent evidence of accelerating climate change, has brought increasing urgency to the search for additional remediation approaches.  This book presents a selection of state-of-the-art geoengineering methods for deliberately reducing the effects of anthropogenic climate change, either by actively removing greenhouse gases from the atmosphere or by decreasing the amount of sunlight absorbed at the Earth’s surface.  These methods contrast with more conventional mitigation approaches which focus on reducing emissions of greenhouse gases, especially carbon dioxide. Geoengineering technologies could become a key tool to be used in conjunction with emissions reduction to limit the magnitude of climate change.  Featuring authoritative, peer-reviewed entries from the Encyclopedia of Sustainability Science and Technology, this book presents a wide range of climate change remediation technologies. Examines th...

Conception and syllabus on radiochemistry and radioecology principles for general student groups of a university chemical department

International Nuclear Information System (INIS)

Bogdanov, R.V.

1994-01-01

The problem of basic principles of selecting materials for general courses on diverse subjects in chemical science is discussed. Relying on certain general rules and proceeding from specificity of radiochemistry, the author suggests a variant of syllabus including radiochemical and radioecological blocks intented for 48 academic hours. In methodical respect emphasis is made on theoretical material presentation in close combination with various nuclear methods used in chemical studies. 6 refs., 1 fig

Chemically induced transition phenomena in polyurethanes as seen from generalized mode Grueneisen parameters

Energy Technology Data Exchange (ETDEWEB)

Mueller, U; Philipp, M; Bactavatchalou, R; Sanctuary, R; Baller, J; Zielinski, B; Krueger, J K [Laboratoire de Physique des Materiaux, Universite du Luxembourg, 162A, Avenue de la Faiencerie, L-1115 (Luxembourg); Possart, W; Alnot, P [Laboratoire Europeen de Recherche, Universitaire Saarland-Lorraine (Luxembourg)], E-mail: ulrich.mueller@uni.lu

2008-05-21

Many phenomenological properties of reactive polymers like polyurethanes increase or decrease continuously in the course of the curing process before saturating at the end of the chemical reaction. This holds true for instance for the mass density, the refractive index, the chemical turnover and the hypersonic properties. The reason for this monotone behaviour is that the chemical reaction behaves like a continuous succession of irreversible phase transitions. These transitions are superposed by the sol-gel transition and possibly by the chemically induced glass transition, with the drawback that the latter two highlighted transitions are often hidden by the underlying curing process. In this work we propose generalized mode Grueneisen parameters as an alternative probe for elucidating the polymerization process itself and the closely related transition phenomena. As a model system we use polyurethane composed of a diisocyanate and varying ratios of difunctional and trifunctional alcohols.

Phenotypes of individuals affected by airborne chemicals in the general population

DEFF Research Database (Denmark)

Berg, Nikolaj Drimer; Linneberg, A.; Dirksen, Asger

2009-01-01

to symptoms than less severely affected individuals, and the number of symptoms was more predictive for severity than the number of exposures. Most predictive for the severity of reported symptoms were CNS-symptoms other than headache (OR = 3.2, P ... (OR = 2.0, P = 0.001). CONCLUSION: CNS-symptoms except from headache were a main characteristic of individuals severely affected by common chemical exposures in a general population-based sample...

Some Matrix Iterations for Computing Generalized Inverses and Balancing Chemical Equations

OpenAIRE

Soleimani, Farahnaz; Stanimirovi´c, Predrag; Soleymani, Fazlollah

2015-01-01

An application of iterative methods for computing the Moore–Penrose inverse in balancing chemical equations is considered. With the aim to illustrate proposed algorithms, an improved high order hyper-power matrix iterative method for computing generalized inverses is introduced and applied. The improvements of the hyper-power iterative scheme are based on its proper factorization, as well as on the possibility to accelerate the iterations in the initial phase of the convergence. Although the ...

General considerations on the oxide fuel-cladding chemical interaction

International Nuclear Information System (INIS)

Pascard, R.

1977-01-01

Since the very first experimental irradiations in thermal reactors, performed in view of the future Rapsodie fuel general study, corrosion cladding anomalies were observed. After 10 years of Rapsodie and more than two years of Phenix, performance brought definite confirmation of the chemical reactions between the irradiated fuel and cladding. That is the reason for which the fuel designers express an urgent need for determining the corrosion rates. Semi-empirical laws and mechanisms describing corrosion processes are proposed. Erratic conditions for appearance of the oxide-cladding corrosion are stressed upon. Obviously such a problem can be fully appreciated only by a statistical approach based on a large number of observations on the true LMFBR fuel pins

Encyclopedia of Information Ethics and Security

Directory of Open Access Journals (Sweden)

Reviewed by Yavuz AKBULUT

2008-01-01

Full Text Available 233Rapid developments in information andcommunication technologies have created newsecurity threats along with ethical dilemmas. Thesedevelopments have been so fast that appropriatesecurity precautions and ethical codes fail to keeppace with the technological developments. In thisrespect, education of both professionals andordinary citizens regarding information technologyethics carries utmost importance. Encyclopedia ofInformation Ethics and Security serves as anauthentic and comprehensive reference source onsecurity and ethical issues related to informationand communication technologies. The encyclopediais consisted of 661 pages (+xvii covering a total of95 alphabetically ordered chapters on informationethics and security, which are followed by twocomprehensive sets of indexes. Each entry is anauthoritative contribution followed by in-depthdefinitions of relevant terminology and acronyms.The total number of key terms included in the encyclopedia is approximately 700. Thesource also includes more than 2000 references to existing literature on ethical andsecurity issues related to information and communication technologies. A total of 148respected scholars and leading experts all around the world contributed to the source.As indicated in the preface of the encyclopedia by editor, all entries were subjected toan initial double-blind peer review and an additional review prior to acceptance forpublication. Chapters mostly have parallel layouts beginning with a clear introductionfollowed by the theoretical background and the contribution. Each chapter concludeswith invaluable ethical implications for the field along with suggestions for furtherThe editor, Marian Quigley (PhD – Monash University, Australia; BA – ChisholmInstitute of Technology, Australia; Higher Diploma of Teaching Secondary [Art andCraft] is a former senior lecturer in the Faculty of Information Technology, MonashUniversity, Australia. She primarily works on the social effects

Generalized Least Energy of Separation for Desalination and Other Chemical Separation Processes

Directory of Open Access Journals (Sweden)

Karan H. Mistry

2013-05-01

Full Text Available Increasing global demand for fresh water is driving the development and implementation of a wide variety of seawater desalination technologies driven by different combinations of heat, work, and chemical energy. This paper develops a consistent basis for comparing the energy consumption of such technologies using Second Law efficiency. The Second Law efficiency for a chemical separation process is defined in terms of the useful exergy output, which is the minimum least work of separation required to extract a unit of product from a feed stream of a given composition. For a desalination process, this is the minimum least work of separation for producing one kilogram of product water from feed of a given salinity. While definitions in terms of work and heat input have been proposed before, this work generalizes the Second Law efficiency to allow for systems that operate on a combination of energy inputs, including fuel. The generalized equation is then evaluated through a parametric study considering work input, heat inputs at various temperatures, and various chemical fuel inputs. Further, since most modern, large-scale desalination plants operate in cogeneration schemes, a methodology for correctly evaluating Second Law efficiency for the desalination plant based on primary energy inputs is demonstrated. It is shown that, from a strictly energetic point of view and based on currently available technology, cogeneration using electricity to power a reverse osmosis system is energetically superior to thermal systems such as multiple effect distillation and multistage flash distillation, despite the very low grade heat input normally applied in those systems.

General-purpose chemical analyzer for on-line analyses of radioactive solutions

International Nuclear Information System (INIS)

Spencer, W.A.; Kronberg, J.W.

1983-01-01

An automated analyzer is being developed to perform analytical measurements on radioactive solutions on-line in a hostile environment. This General Purpose Chemical Analyzer (GPCA) samples a process stream, adds reagents, measures solution absorbances or electrode potentials, and automatically calculates the results. The use of modular components, under microprocessor control, permits a single analyzer design to carry out many types of analyses. This paper discusses the more important design criteria for the GPCA, and describes the equipment being tested in a prototype unit

Encyclopedia of two-phase heat transfer and flow III macro and micro flow boiling and numerical modeling fundamentals

CERN Document Server

2018-01-01

Set III of this encyclopedia is a new addition to the previous Sets I and II. It contains 26 invited chapters from international specialists on the topics of numerical modeling of two-phase flows and evaporation, fundamentals of evaporation and condensation in microchannels and macrochannels, development and testing of micro two-phase cooling systems for electronics, and various special topics (surface wetting effects, microfin tubes, two-phase flow vibration across tube bundles). The chapters are written both by renowned university researchers and by well-known engineers from leading corporate research laboratories. Numerous "must read" chapters cover the fundamentals of research and engineering practice on boiling, condensation and two-phase flows, two-phase heat transfer equipment, electronics cooling systems, case studies and so forth. Set III constitutes a "must have" reference together with Sets I and II for thermal engineering researchers and practitioners.

Relativistic Spin-Orbit Heavy Atom on the Light Atom NMR Chemical Shifts: General Trends Across the Periodic Table Explained.

Science.gov (United States)

Vícha, Jan; Komorovsky, Stanislav; Repisky, Michal; Marek, Radek; Straka, Michal

2018-05-10

The importance of relativistic effects on the NMR parameters in heavy-atom (HA) compounds, particularly the SO-HALA (Spin-Orbit Heavy Atom on the Light Atom) effect on NMR chemical shifts, has been known for about 40 years. Yet, a general correlation between the electronic structure and SO-HALA effect has been missing. By analyzing 1 H NMR chemical shifts of the sixth-period hydrides (Cs-At), we discovered general electronic-structure principles and mechanisms that dictate the size and sign of the SO-HALA NMR chemical shifts. In brief, partially occupied HA valence shells induce relativistic shielding at the light atom (LA) nuclei, while empty HA valence shells induce relativistic deshielding. In particular, the LA nucleus is relativistically shielded in 5d 2 -5d 8 and 6p 4 HA hydrides and deshielded in 4f 0 , 5d 0 , 6s 0 , and 6p 0 HA hydrides. This general and intuitive concept explains periodic trends in the 1 H NMR chemical shifts along the sixth-period hydrides (Cs-At) studied in this work. We present substantial evidence that the introduced principles have a general validity across the periodic table and can be extended to nonhydride LAs. The decades-old question of why compounds with occupied frontier π molecular orbitals (MOs) cause SO-HALA shielding at the LA nuclei, while the frontier σ MOs cause deshielding is answered. We further derive connection between the SO-HALA NMR chemical shifts and Spin-Orbit-induced Electron Deformation Density (SO-EDD), a property that can be obtained easily from differential electron densities and can be represented graphically. SO-EDD provides an intuitive understanding of the SO-HALA effect in terms of the depletion/concentration of the electron density at LA nuclei caused by spin-orbit coupling due to HA in the presence of a magnetic field. Using an analogy between the SO-EDD concept and arguments from classic NMR theory, the complex question of the SO-HALA NMR chemical shifts becomes easily understandable for a wide

A new general methodology for incorporating physico-chemical transformations into multi-phase wastewater treatment process models.

Science.gov (United States)

Lizarralde, I; Fernández-Arévalo, T; Brouckaert, C; Vanrolleghem, P; Ikumi, D S; Ekama, G A; Ayesa, E; Grau, P

2015-05-01

This paper introduces a new general methodology for incorporating physico-chemical and chemical transformations into multi-phase wastewater treatment process models in a systematic and rigorous way under a Plant-Wide modelling (PWM) framework. The methodology presented in this paper requires the selection of the relevant biochemical, chemical and physico-chemical transformations taking place and the definition of the mass transport for the co-existing phases. As an example a mathematical model has been constructed to describe a system for biological COD, nitrogen and phosphorus removal, liquid-gas transfer, precipitation processes, and chemical reactions. The capability of the model has been tested by comparing simulated and experimental results for a nutrient removal system with sludge digestion. Finally, a scenario analysis has been undertaken to show the potential of the obtained mathematical model to study phosphorus recovery. Copyright © 2015 Elsevier Ltd. All rights reserved.

Genetics Home Reference: Müllerian aplasia and hyperandrogenism

Science.gov (United States)

... do not begin menstruation by age 16 (primary amenorrhea) and will likely never have a menstrual period. ... Encyclopedia: Ovarian Overproduction of Androgens MedlinePlus Encyclopedia: Primary Amenorrhea General Information from MedlinePlus (5 links) Diagnostic Tests ...

Genetics Home Reference: Donnai-Barrow syndrome

Science.gov (United States)

... opening in the wall of the abdomen (an omphalocele ) that allows the abdominal organs to protrude through ... Hernia MedlinePlus Encyclopedia: Hearing Loss - Infants MedlinePlus Encyclopedia: Omphalocele Nemours Foundation: Hearing Evaluation in Children General Information ...

Genetics Home Reference: focal dermal hypoplasia

Science.gov (United States)

... in people with focal dermal hypoplasia is an omphalocele , which is an opening in the wall of ... Dermal Hypoplasia MedlinePlus Encyclopedia: Ectodermal dysplasia MedlinePlus Encyclopedia: Omphalocele General Information from MedlinePlus (5 links) Diagnostic Tests ...

Genetics Home Reference: Beckwith-Wiedemann syndrome

Science.gov (United States)

... opening in the wall of the abdomen (an omphalocele ) that allows the abdominal organs to protrude through ... Beckwith-Wiedemann syndrome MedlinePlus Encyclopedia: Macroglossia MedlinePlus Encyclopedia: Omphalocele General Information from MedlinePlus (5 links) Diagnostic Tests ...

Prototyping Aplikasi E-Health sebagai Bagian Pengenalan Obat-Obatan Dengan Teknologi Cross-Platform

Directory of Open Access Journals (Sweden)

Ari Muzakir

2018-01-01

Full Text Available Nowadays peoples usually do various ways to know the types and benefits of medicines to solve their symptoms. For example they do search information through Internet, but they don’t know the appropriate drug to consume according their symptoms. This research aimed to build an encyclopedia about E-Health-based drugs. By utilizing encyclopedia about E-Health-based drugs, its much easier to most peoples to understand and recognize various types of medicines including herbal and chemical medicines. The result of this research is an application prototype about encyclopedia of E-Health-based drugs that runs on web and mobile platforms tested by blacbox method. Furthermore, the result of this research, can be a basis to develop a larger and functional E-Health-based drugs encyclopedia modules.

Genetics Home Reference: Naegeli-Franceschetti-Jadassohn syndrome/dermatopathia pigmentosa reticularis

Science.gov (United States)

... reticularis ( NFJS/DPR ) represents a rare type of ectodermal dysplasia, a group of about 150 conditions characterized by ... Related Skin Types (FIRST): Palmoplantar Keratodermas MedlinePlus Encyclopedia: Ectodermal Dysplasia MedlinePlus Encyclopedia: Nail Abnormalities General Information from MedlinePlus ( ...

ENVIRONMENTS and EOL: identification of Environment Ontology terms in text and the annotation of the Encyclopedia of Life.

Science.gov (United States)

Pafilis, Evangelos; Frankild, Sune P; Schnetzer, Julia; Fanini, Lucia; Faulwetter, Sarah; Pavloudi, Christina; Vasileiadou, Katerina; Leary, Patrick; Hammock, Jennifer; Schulz, Katja; Parr, Cynthia Sims; Arvanitidis, Christos; Jensen, Lars Juhl

2015-06-01

The association of organisms to their environments is a key issue in exploring biodiversity patterns. This knowledge has traditionally been scattered, but textual descriptions of taxa and their habitats are now being consolidated in centralized resources. However, structured annotations are needed to facilitate large-scale analyses. Therefore, we developed ENVIRONMENTS, a fast dictionary-based tagger capable of identifying Environment Ontology (ENVO) terms in text. We evaluate the accuracy of the tagger on a new manually curated corpus of 600 Encyclopedia of Life (EOL) species pages. We use the tagger to associate taxa with environments by tagging EOL text content monthly, and integrate the results into the EOL to disseminate them to a broad audience of users. The software and the corpus are available under the open-source BSD and the CC-BY-NC-SA 3.0 licenses, respectively, at http://environments.hcmr.gr. © The Author 2015. Published by Oxford University Press.

General areas needing chemical competence to support reactor operation

International Nuclear Information System (INIS)

Proksch, E.; Bildstein, H.

1963-01-01

Chemical competence is needed not only for the development of new types of reactors but also for the start-up and safe operation of reactors. The activities of chemistry and chemical engineering cover a number of fields, namely chemical analysis, radiochemical analysis, corrosion research, radiolysis of water and water purification. The author reviews fields in reactor operation and maintenance in which chemical competence is needed. (author). 9 refs

Quality Assessment of Soaps Produced from Palm Bunch Ash ...

African Journals Online (AJOL)

Michael Horsfall

black soap counterpart considering some physico-chemical properties such as matter insoluble in water ... materials which are non-toxic and potentially suitable for alkali generation .... 0.2% for toilet soap (encyclopedia of industrial chemical ...

Development of a general model for determination of thermal conductivity of liquid chemical compounds at atmospheric pressure

DEFF Research Database (Denmark)

Gharagheizi, Farhad; Ilani‐Kashkouli, Poorandokht; Sattari, Mehdi

2013-01-01

In this communication, a general model for representation/presentation of the liquid thermal conductivity of chemical compounds (mostly organic) at 1 atm pressure for temperatures below normal boiling point and at saturation pressure for temperatures above the normal boiling point is developed...... using the Gene Expression Programming algorithm. Approximately 19,000 liquid thermal conductivity data at different temperatures related to 1636 chemical compounds collected from the DIPPR 801 database are used to obtain the model as well as to assess its predictive capability. The parameters...

The StarDate Black Hole Encyclopedia Website blackholes.stardate.org

Science.gov (United States)

Gebhardt, Karl; Benningfield, D.; Preston, S.

2013-01-01

The StarDate Black Hole Encyclopedia website was developed over the past seven years to provide an extensive but easy-to-read resource for the public and students. A Spanish-language version, Enciclopedia de agujeros negros, is also available at blackholes.radiouniverso.org. Evaluation shows that the sites are used by the public, students, and astronomy professionals, and the site is among the top references in most web searches for individual black holes. The site comprises seven major subsections: Basics, Directory, Research, History, Pop Culture, News, and Resources. The Basics section introduces black holes, explains how they are discovered and studied, and covers their basis in the theory of gravity. This section also includes a six-minute video introduction, “Black Holes: Stranger than Fiction.” The Directory section contains extensive descriptions of more than 80 well-known stellar, intermediate, and supermassive black holes as well as images and vital statistics of each. The Research section takes a look at three NSF-funded projects, including the work of Andrea Ghez, Karl Gebhardt and Jenny Greene, and the LIGO project. The History section provides a timeline of black holes from Isaac Newton to the present. Some of the best and worst roles played by black holes in films, TV shows, and books are included in the Pop Culture section (and pop culture references and images are sprinkled through the rest of the site). An archive of news reports about black holes is available in the News section, which provides links to the original stories or press releases. And the Resources section offers FAQs, articles from StarDate magazine and radio programs, activities for students that are tied to national standards, a glossary, and a reading list of books and websites. We have conducted both quantitative and qualitative evaluation on the black hole websites. This material is based upon work supported by the National Science Foundation under Grant No. 0935841. Any

The General Laws of Chemical Elements Composition Dynamics in the Biosphere

Science.gov (United States)

Korzh, Vyacheslav D.

2013-04-01

The key point of investigation of the specificity of the biosphere elemental composition formation is determination of patterns of redistribution of elemental average concentrations among various phases, like solid - liquid ( the lithosphere - the hydrosphere), which occurs as a result of a global continuous processing of inert matter by living substances. Our task here is to investigate this process in the system "lithosphere - hydrosphere" in view of the integrated involvement of living material in it. This process is most active in biogeochemical barriers, i.e. in places of "the life condensation" and runs under a nonlinear regularity that has been unknown before. It is established that this process results in a general relative increase in concentrations of chemical elements in the solid phase in proportion as their prevalence in the environment is reduced. This process running in various natural systems has practically the same parameter of nonlinearity (v) approximately equal to 0.7. For proto-lithosphere -"living material" - soil v = 0.75. For river - "living material" - ocean v = 0.67. For the contemporary factual awareness level these estimations of nonlinearity indices are practically negligible. Hence, it is for the first time that the existence of a universal constant of nonlinearity of elemental composition evolution in the biosphere has been proved and its quantitative evaluation has been made. REFERENCES 1. Korzh V.D. 1974. Some general laws governing the turnover of substance within the ocean-atmosphere-continent-ocean cycle. // Journal de Recherches Atmospheriques. Vol. 8. P. 653-660. 2. Korzh V.D. 2008. The general laws in the formation of the elemental composition of the Hydrosphere and Biosphere.// J. Ecologica, Vol. XV, P. 13-21. 3. Korzh V.D. 2012. Determination of general laws of elemental composition in Hydrosphere // Water: chemistry & ecology, Journal of water science and its practical application. # 1, P.56-62.

Chemical restraint in routine clinical practice: a report from a general hospital psychiatric ward in Greece

Directory of Open Access Journals (Sweden)

Papamichael Georgios

2011-02-01

Full Text Available Abstract Background There is a dearth of studies regarding chemical restraint in routine clinical psychiatric practice. There may be wide variations between different settings and countries. Methods A retrospective study on chemical restraint was performed in the 11-bed psychiatric ward of the General Hospital of Arta, in northwestern Greece. All admissions over a 2-year-period (from March 2008 to March 2010 were examined. Results Chemical restraint was applied in 33 cases (10.5% of total admissions. From a total of 82 injections, 22 involved a benzodiazepine and/or levomepromazine, whereas 60 injections involved an antipsychotic agent, almost exclusively haloperidol (96.7% of cases, usually in combination with a benzodiazepine (61.7% of cases. In 36.4% of cases the patient was further subjected to restraint or seclusion. Conclusions In our unit, clinicians prefer the combined antipsychotic/benzodiazepine regimen for the management of patients' acute agitation and violent behaviour. Conventional antipsychotics are administrated almost exclusively and in a significant proportion of cases further coercive measures are applied. Studies on the practice of chemical restraint should be regularly performed in clinical settings.

Online general pre-laboratory training course for facilitating first year chemical laboratory use

Directory of Open Access Journals (Sweden)

Maria Limniou

2010-03-01

Full Text Available In Chemistry, practical work is a highly demanding process in which students should be well-prepared before and alert during,laboratory sessions. Various general difficulties such as the limited laboratory time and the lack of connections between theoryand practicals often do not allow students to actively participate in the learning process. The aim of this investigation is to studyhow an online general pre-laboratory training course inspired by cognitive load theory influenced the teaching of first yearchemistry students engaged in laboratory work. Two different groups of chemistry students (experimental group (EG andcontrol group (CG from the University of Manchester participated in this investigation. The EG group participated in the onlinepre-laboratory course before entering the laboratory, while the CG group performed the experiments following the traditionalteaching procedure. The comparison of students’ responses to the same assessments of fundamental chemical and basiclaboratory knowledge showed that overall the performance of the EG group of students was higher than that of the CGstudents. Overall, the EG students valued the opportunity to have an online training course. By creating a flexible learningenvironment which included animations, simulations and self-assessments, the general laboratory difficulties were overcome.These interactive learning features gave students the opportunity to engage in independent study, by which restrictions of timeand place were overcome.

Chemical Waste Management and Disposal.

Science.gov (United States)

Armour, Margaret-Ann

1988-01-01

Describes simple, efficient techniques for treating hazardous chemicals so that nontoxic and nonhazardous residues are formed. Discusses general rules for management of waste chemicals from school laboratories and general techniques for the disposal of waste or surplus chemicals. Lists specific disposal reactions. (CW)

The Encyclopedia of Life v2: Providing Global Access to Knowledge About Life on Earth

Science.gov (United States)

2014-01-01

Abstract The Encyclopedia of Life (EOL, http://eol.org) aims to provide unprecedented global access to a broad range of information about life on Earth. It currently contains 3.5 million distinct pages for taxa and provides content for 1.3 million of those pages. The content is primarily contributed by EOL content partners (providers) that have a more limited geographic, taxonomic or topical scope. EOL aggregates these data and automatically integrates them based on associated scientific names and other classification information. EOL also provides interfaces for curation and direct content addition. All materials in EOL are either in the public domain or licensed under a Creative Commons license. In addition to the web interface, EOL is also accessible through an Application Programming Interface. In this paper, we review recent developments added for Version 2 of the web site and subsequent releases through Version 2.2, which have made EOL more engaging, personal, accessible and internationalizable. We outline the core features and technical architecture of the system. We summarize milestones achieved so far by EOL to present results of the current system implementation and establish benchmarks upon which to judge future improvements. We have shown that it is possible to successfully integrate large amounts of descriptive biodiversity data from diverse sources into a robust, standards-based, dynamic, and scalable infrastructure. Increasing global participation and the emergence of EOL-powered applications demonstrate that EOL is becoming a significant resource for anyone interested in biological diversity. PMID:24891832

Molecular basis sets - a general similarity-based approach for representing chemical spaces.

Science.gov (United States)

Raghavendra, Akshay S; Maggiora, Gerald M

2007-01-01

A new method, based on generalized Fourier analysis, is described that utilizes the concept of "molecular basis sets" to represent chemical space within an abstract vector space. The basis vectors in this space are abstract molecular vectors. Inner products among the basis vectors are determined using an ansatz that associates molecular similarities between pairs of molecules with their corresponding inner products. Moreover, the fact that similarities between pairs of molecules are, in essentially all cases, nonzero implies that the abstract molecular basis vectors are nonorthogonal, but since the similarity of a molecule with itself is unity, the molecular vectors are normalized to unity. A symmetric orthogonalization procedure, which optimally preserves the character of the original set of molecular basis vectors, is used to construct appropriate orthonormal basis sets. Molecules can then be represented, in general, by sets of orthonormal "molecule-like" basis vectors within a proper Euclidean vector space. However, the dimension of the space can become quite large. Thus, the work presented here assesses the effect of basis set size on a number of properties including the average squared error and average norm of molecular vectors represented in the space-the results clearly show the expected reduction in average squared error and increase in average norm as the basis set size is increased. Several distance-based statistics are also considered. These include the distribution of distances and their differences with respect to basis sets of differing size and several comparative distance measures such as Spearman rank correlation and Kruscal stress. All of the measures show that, even though the dimension can be high, the chemical spaces they represent, nonetheless, behave in a well-controlled and reasonable manner. Other abstract vector spaces analogous to that described here can also be constructed providing that the appropriate inner products can be directly

Microelectrode voltammetry of multi-electron transfers complicated by coupled chemical equilibria: a general theory for the extended square scheme.

Science.gov (United States)

Laborda, Eduardo; Gómez-Gil, José María; Molina, Angela

2017-06-28

A very general and simple theoretical solution is presented for the current-potential-time response of reversible multi-electron transfer processes complicated by homogeneous chemical equilibria (the so-called extended square scheme). The expressions presented here are applicable regardless of the number of electrons transferred and coupled chemical processes, and they are particularized for a wide variety of microelectrode geometries. The voltammetric response of very different systems presenting multi-electron transfers is considered for the most widely-used techniques (namely, cyclic voltammetry, square wave voltammetry, differential pulse voltammetry and steady state voltammetry), studying the influence of the microelectrode geometry and the number and thermodynamics of the (electro)chemical steps. Most appropriate techniques and procedures for the determination of the 'interaction' between successive transfers are discussed. Special attention is paid to those situations where homogeneous chemical processes, such as protonation, complexation or ion association, affect the electrochemical behaviour of the system by different stabilization of the oxidation states.

Composition and production rate of pharmaceutical and chemical waste from Xanthi General Hospital in Greece.

Science.gov (United States)

Voudrias, Evangelos; Goudakou, Lambrini; Kermenidou, Marianthi; Softa, Aikaterini

2012-07-01

The objective of this work was to determine the composition and production rates of pharmaceutical and chemical waste produced by Xanthi General Hospital in Greece (XGH). This information is important to design and cost management systems for pharmaceutical and chemical waste, for safety and health considerations and for assessing environmental impact. A total of 233 kg pharmaceutical and 110 kg chemical waste was collected, manually separated and weighed over a period of five working weeks. The total production of pharmaceutical waste comprised 3.9% w/w of the total hazardous medical waste produced by the hospital. Total pharmaceutical waste was classified in three categories, vial waste comprising 51.1%, syringe waste with 11.4% and intravenous therapy (IV) waste with 37.5% w/w of the total. Vial pharmaceutical waste only was further classified in six major categories: antibiotics, digestive system drugs, analgesics, hormones, circulatory system drugs and "other". Production data below are presented as average (standard deviation in parenthesis). The unit production rates for total pharmaceutical waste for the hospital were 12.4 (3.90) g/patient/d and 24.6 (7.48) g/bed/d. The respective unit production rates were: (1) for vial waste 6.4 (1.6) g/patient/d and 13 (2.6) g/bed/d, (2) for syringe waste 1.4 (0.4) g/patient/d and 2.8 (0.8) g/bed/d and (3) for IV waste 4.6 (3.0) g/patient/d and 9.2 (5.9) g/bed/d. Total chemical waste was classified in four categories, chemical reagents comprising 18.2%, solvents with 52.3%, dyes and tracers with 18.2% and solid waste with 11.4% w/w of the total. The total production of chemical waste comprised 1.8% w/w of the total hazardous medical waste produced by the hospital. Thus, the sum of pharmaceutical and chemical waste was 5.7% w/w of the total hazardous medical waste produced by the hospital. The unit production rates for total chemical waste for the hospital were 5.8 (2.2) g/patient/d and 1.1 (0.4) g/exam/d. The respective

Generalization of predator recognition: Velvet geckos display anti-predator behaviours in response to chemicals from non-dangerous elapid snakes

Directory of Open Access Journals (Sweden)

Jonathan K. WEBB, Weiguo DU, David PIKE, Richard SHINE

2010-06-01

Full Text Available Many prey species detect chemical cues from predators and modify their behaviours in ways that reduce their risk of predation. Theory predicts that prey should modify their anti-predator responses according to the degree of threat posed by the predator. That is, prey should show the strongest responses to chemicals of highly dangerous prey, but should ignore or respond weakly to chemicals from non-dangerous predators. However, if anti-predator behaviours are not costly, and predators are rarely encountered, prey may exhibit generalised antipredator behaviours to dangerous and non-dangerous predators. In Australia, most elapid snakes eat lizards, and are therefore potentially dangerous to lizard prey. Recently, we found that the nocturnal velvet gecko Oedura lesueurii responds to chemicals from dangerous and non-dangerous elapid snakes, suggesting that it displays generalised anti-predator behaviours to chemicals from elapid snakes. To explore the generality of this result, we videotaped the behaviour of velvet geckos in the presence of chemical cues from two small elapid snakes that rarely consume geckos: the nocturnal golden-crowned snake Cacophis squamulosus and the diurnal marsh snake Hemiaspis signata. We also videotaped geckos in trials involving unscented cards (controls and cologne-scented cards (pungency controls. In trials involving Cacophis and Hemiaspis chemicals, 50% and 63% of geckos spent long time periods (> 3 min freezing whilst pressed flat against the substrate, respectively. Over half the geckos tested exhibited anti-predator behaviours (tail waving, tail vibration, running in response to Cacophis (67% or Hemiaspis (63% chemicals. These behaviours were not observed in control or pungency control trials. Our results support the idea that the velvet gecko displays generalised anti-predator responses to chemical cues from elapid snakes. Generalised responses to predator chemicals may be common in prey species that co-occur with

Composition and production rate of pharmaceutical and chemical waste from Xanthi General Hospital in Greece

International Nuclear Information System (INIS)

Voudrias, Evangelos; Goudakou, Lambrini; Kermenidou, Marianthi; Softa, Aikaterini

2012-01-01

Highlights: ► We studied pharmaceutical and chemical waste production in a Greek hospital. ► Pharmaceutical waste comprised 3.9% w/w of total hazardous medical waste. ► Unit production rate for total pharmaceutical waste was 12.4 ± 3.90 g/patient/d. ► Chemical waste comprised 1.8% w/w of total hazardous medical waste. ► Unit production rate for total chemical waste was 5.8 ± 2.2 g/patient/d. - Abstract: The objective of this work was to determine the composition and production rates of pharmaceutical and chemical waste produced by Xanthi General Hospital in Greece (XGH). This information is important to design and cost management systems for pharmaceutical and chemical waste, for safety and health considerations and for assessing environmental impact. A total of 233 kg pharmaceutical and 110 kg chemical waste was collected, manually separated and weighed over a period of five working weeks. The total production of pharmaceutical waste comprised 3.9% w/w of the total hazardous medical waste produced by the hospital. Total pharmaceutical waste was classified in three categories, vial waste comprising 51.1%, syringe waste with 11.4% and intravenous therapy (IV) waste with 37.5% w/w of the total. Vial pharmaceutical waste only was further classified in six major categories: antibiotics, digestive system drugs, analgesics, hormones, circulatory system drugs and “other”. Production data below are presented as average (standard deviation in parenthesis). The unit production rates for total pharmaceutical waste for the hospital were 12.4 (3.90) g/patient/d and 24.6 (7.48) g/bed/d. The respective unit production rates were: (1) for vial waste 6.4 (1.6) g/patient/d and 13 (2.6) g/bed/d, (2) for syringe waste 1.4 (0.4) g/patient/d and 2.8 (0.8) g/bed/d and (3) for IV waste 4.6 (3.0) g/patient/d and 9.2 (5.9) g/bed/d. Total chemical waste was classified in four categories, chemical reagents comprising 18.2%, solvents with 52.3%, dyes and tracers with 18.2% and

CHEMICALS

CERN Multimedia

Medical Service

2002-01-01

It is reminded that all persons who use chemicals must inform CERN's Chemistry Service (TIS-GS-GC) and the CERN Medical Service (TIS-ME). Information concerning their toxicity or other hazards as well as the necessary individual and collective protection measures will be provided by these two services. Users must be in possession of a material safety data sheet (MSDS) for each chemical used. These can be obtained by one of several means : the manufacturer of the chemical (legally obliged to supply an MSDS for each chemical delivered) ; CERN's Chemistry Service of the General Safety Group of TIS ; for chemicals and gases available in the CERN Stores the MSDS has been made available via EDH either in pdf format or else via a link to the supplier's web site. Training courses in chemical safety are available for registration via HR-TD. CERN Medical Service : TIS-ME :73186 or service.medical@cern.ch Chemistry Service : TIS-GS-GC : 78546

A systematic study on drug-response associated genes using baseline gene expressions of the Cancer Cell Line Encyclopedia

Science.gov (United States)

Liu, Xiaoming; Yang, Jiasheng; Zhang, Yi; Fang, Yun; Wang, Fayou; Wang, Jun; Zheng, Xiaoqi; Yang, Jialiang

2016-03-01

We have studied drug-response associated (DRA) gene expressions by applying a systems biology framework to the Cancer Cell Line Encyclopedia data. More than 4,000 genes are inferred to be DRA for at least one drug, while the number of DRA genes for each drug varies dramatically from almost 0 to 1,226. Functional enrichment analysis shows that the DRA genes are significantly enriched in genes associated with cell cycle and plasma membrane. Moreover, there might be two patterns of DRA genes between genders. There are significantly shared DRA genes between male and female for most drugs, while very little DRA genes tend to be shared between the two genders for a few drugs targeting sex-specific cancers (e.g., PD-0332991 for breast cancer and ovarian cancer). Our analyses also show substantial difference for DRA genes between young and old samples, suggesting the necessity of considering the age effects for personalized medicine in cancers. Lastly, differential module and key driver analyses confirm cell cycle related modules as top differential ones for drug sensitivity. The analyses also reveal the role of TSPO, TP53, and many other immune or cell cycle related genes as important key drivers for DRA network modules. These key drivers provide new drug targets to improve the sensitivity of cancer therapy.

Chemical intermediate detection following corona discharge on volatile organic compounds: general method using molecular beam techniques

International Nuclear Information System (INIS)

He Luning; Sulkes, Mark

2011-01-01

Nonthermal plasma (NTP)-based treatments of volatile organic compounds (VOCs) have potential for effective environmental remediation. Theory and experiment that consider the basic science pertaining to discharge events have helped improve NTP remediation outcomes. If direct information on early post-discharge chemical intermediates were also available, it would likely lead to additional improvement in NTP remediation outcomes. To this point, however, experiments yielding direct information on post-NTP VOC intermediates have been limited. An approach using supersonic expansion molecular beam methods offers general promise for detection of post-discharge VOC intermediates. To illustrate the potential utility of these methods, we present mass spectra showing the growth of early products formed when pulsed corona discharges were carried out on toluene in He and then in He with added O 2 . Good general detection of neutral post-discharge species was obtained using 800 nm 150 fs photoionization pulses.

Chemical Risk Assessment

Science.gov (United States)

This course is aimed at providing an overview of the fundamental guiding principles and general methods used in chemical risk assessment. Chemical risk assessment is a complex and ever-evolving process. These principles and methods have been organized by the National Research Cou...

Potential Impacts of Spilled Hydraulic Fracturing Fluid Chemicals on Water Resources: Types, volumes, and physical-chemical properties of chemicals

Science.gov (United States)

Hydraulic fracturing (HF) fluid chemicals spilled on-site may impact drinking water resources. While chemicals generally make up <2% of the total injected fluid composition by mass, spills may have undiluted concentrations. HF fluids typically consist of a mixture of base flui...

Design of chemical plant

International Nuclear Information System (INIS)

Lee, Dong Il; Kim, Seung Jae; Yang, Jae Ho; Ryu, Hwa Won

1993-01-01

This book describes design of chemical plant, which includes chemical engineer and plan for chemical plant, development of chemical process, cost engineering pattern, design and process development, general plant construction plan, project engineering, foundation for economy on assets and depreciation, estimation for cost on capital investment and manufacturing cost, design with computers optimal design and method like fluid mechanics design chemical device and estimation for cost, such as dispatch of material and device writing on design report and appendixes.

General chemistry

International Nuclear Information System (INIS)

Kwon, Yeong Sik; Lee, Dong Seop; Ryu, Haung Ryong; Jang, Cheol Hyeon; Choi, Bong Jong; Choi, Sang Won

1993-07-01

The book concentrates on the latest general chemistry, which is divided int twenty-three chapters. It deals with basic conception and stoichiometry, nature of gas, structure of atoms, quantum mechanics, symbol and structure of an electron of ion and molecule, chemical thermodynamics, nature of solid, change of state and liquid, properties of solution, chemical equilibrium, solution and acid-base, equilibrium of aqueous solution, electrochemistry, chemical reaction speed, molecule spectroscopy, hydrogen, oxygen and water, metallic atom; 1A, IIA, IIIA, carbon and atom IVA, nonmetal atom and an inert gas, transition metals, lanthanons, and actinoids, nuclear properties and radioactivity, biochemistry and environment chemistry.

The latest general chemistry

International Nuclear Information System (INIS)

Ryu, Geun Bae; Choi, Se Yeong; Kim, Chin Yeong; Yoon, Gil Jung; Lee, Eun Seok; Seo, Moon Gyu

1995-02-01

This book deals with the latest general chemistry, which is comprised of twenty-three chapters, the contents of this book are introduction, theory of atoms and molecule, chemical formula and a chemical reaction formula, structure of atoms, nature of atoms and the periodic table, structure of molecule and spectrum, gas, solution, solid, chemical combination, chemical reaction speed, chemical equilibrium, thermal chemistry, oxidation-reduction, electrochemistry, acid-base, complex, aquatic chemistry, air chemistry, nuclear chemistry, metal and nonmetal, organic chemistry and biochemistry. It has exercise in the end of each chapter.

Genetics Home Reference: hypochondroplasia

Science.gov (United States)

... the elbows, a sway of the lower back ( lordosis ), and bowed legs. These signs are generally less ... Management Resources (2 links) GeneReview: Hypochondroplasia MedlinePlus Encyclopedia: Lordosis General Information from MedlinePlus (5 links) Diagnostic Tests ...

LSENS: A General Chemical Kinetics and Sensitivity Analysis Code for homogeneous gas-phase reactions. Part 1: Theory and numerical solution procedures

Science.gov (United States)

Radhakrishnan, Krishnan

1994-01-01

LSENS, the Lewis General Chemical Kinetics and Sensitivity Analysis Code, has been developed for solving complex, homogeneous, gas-phase chemical kinetics problems and contains sensitivity analysis for a variety of problems, including nonisothermal situations. This report is part 1 of a series of three reference publications that describe LENS, provide a detailed guide to its usage, and present many example problems. Part 1 derives the governing equations and describes the numerical solution procedures for the types of problems that can be solved. The accuracy and efficiency of LSENS are examined by means of various test problems, and comparisons with other methods and codes are presented. LSENS is a flexible, convenient, accurate, and efficient solver for chemical reaction problems such as static system; steady, one-dimensional, inviscid flow; reaction behind incident shock wave, including boundary layer correction; and perfectly stirred (highly backmixed) reactor. In addition, the chemical equilibrium state can be computed for the following assigned states: temperature and pressure, enthalpy and pressure, temperature and volume, and internal energy and volume. For static problems the code computes the sensitivity coefficients of the dependent variables and their temporal derivatives with respect to the initial values of the dependent variables and/or the three rate coefficient parameters of the chemical reactions.

Chemical kinetics of gas reactions

CERN Document Server

Kondrat'Ev, V N

2013-01-01

Chemical Kinetics of Gas Reactions explores the advances in gas kinetics and thermal, photochemical, electrical discharge, and radiation chemical reactions. This book is composed of 10 chapters, and begins with the presentation of general kinetic rules for simple and complex chemical reactions. The next chapters deal with the experimental methods for evaluating chemical reaction mechanisms and some theories of elementary chemical processes. These topics are followed by discussions on certain class of chemical reactions, including unimolecular, bimolecular, and termolecular reactions. The rema

The Importance of Implementation of the General

Directory of Open Access Journals (Sweden)

Pearson, G. S.

2006-10-01

Full Text Available This paper makes an analysis of international developments over the past five years relating to the implementation of the general purpose criterion which is a central element of the Chemical Weapons Convention that ensures that the Convention covers all toxic chemicals. It examines how some of the recent international initiatives that are addressing chemicals that are of potential risk to public health or to the environment might be harnessed to implement the general purpose criterion thereby strengthening the Convention as a counter to the use of Toxic Industrial Chemicals and other chemicals either by States or by sub-State actors such as terrorists.

Chemical dependency and adolescent self-esteem.

Science.gov (United States)

Wasson, D; Anderson, M A

1995-08-01

The purpose of this descriptive study is to determine whether self-esteem differs between chemically dependent adolescents and adolescents from the general high school population. The Self-Esteem Inventory (Coopersmith, 1987) was completed by 119 adolescents (31 inpatient, 31 aftercare, and 57 general high school students) aged 13 to 18. Findings suggest that inpatient, chemically dependent adolescents have lower self-esteem than the other two groups. For the chemically dependent adolescent, nursing case management with communication among and between health care providers, school professionals, and family may facilitate successful, long-term recovery. For adolescents at risk for development of chemical dependence, nursing health promotion behaviors, such as early assessment and implementation of self-esteem-building activities, may assist in prevention of chemical dependency.

Chemical potential for the interacting classical gas and the ideal quantum gas obeying a generalized exclusion principle

International Nuclear Information System (INIS)

Sevilla, F J; Olivares-Quiroz, L

2012-01-01

In this work, we address the concept of the chemical potential μ in classical and quantum gases towards the calculation of the equation of state μ = μ(n, T) where n is the particle density and T the absolute temperature using the methods of equilibrium statistical mechanics. Two cases seldom discussed in elementary textbooks are presented with detailed calculations. The first one refers to the explicit calculation of μ for the interacting classical gas exemplified by van der Waals gas. For this purpose, we used the method described by van Kampen (1961 Physica 27 783). The second one refers to the calculation of μ for ideal quantum gases that obey a generalized Pauli's exclusion principle that leads to statistics that go beyond the Bose-Einstein and Fermi-Dirac cases. The audience targeted in this work corresponds mainly to advanced undergraduates and graduate students in the physical-chemical sciences but it is not restricted to them. In regard of this, we have put a special emphasis on showing some additional details of calculations that usually do not appear explicitly in textbooks. (paper)

How to control chemical hazards

CERN Multimedia

2012-01-01

Improving protection against chemical hazards is one of the 2012 CERN safety objectives identified by the Director General. Identifying and drawing up a complete inventory of chemicals, and assessing the associated risks are important steps in this direction.   The HSE Unit has drawn up safety rules, guidelines and forms to help you to meet this objective. We would like to draw your attention to: • safety guidelines C-0-0-1 and C-1-0-2 (now also available in French), which deal with the identification of hazardous chemicals and the assessment of chemical risk; • safety guideline C-1-0-1, which deals with the storage of hazardous chemicals. All safety documents can be consulted at: cern.ch/regles-securite The HSE Unit will be happy to answer any questions you may have. Write to us at: safety-general@cern.ch The HSE Unit

Teaching Chemical Equilibrium and Thermodynamics in Undergraduate General Chemistry Classes.

Science.gov (United States)

Banerjee, Anil C.

1995-01-01

Discusses some of the conceptual difficulties encountered by undergraduate students in learning certain aspects of chemical equilibrium and thermodynamics. Discusses teaching strategies for dealing with these difficulties. (JRH)

The Importance of Implementation of the General

OpenAIRE

Pearson, G. S.

2006-01-01

This paper makes an analysis of international developments over the past five years relating to the implementation of the general purpose criterion which is a central element of the Chemical Weapons Convention that ensures that the Convention covers all toxic chemicals. It examines how some of the recent international initiatives that are addressing chemicals that are of potential risk to public health or to the environment might be harnessed to implement the general purpose criterion thereby...

New set of Chemical Safety rules

CERN Multimedia

HSE Unit

2011-01-01

A new set of four Safety Rules was issued on 28 March 2011: Safety Regulation SR-C ver. 2, Chemical Agents (en); General Safety Instruction GSI-C1, Prevention and Protection Measures (en); General Safety Instruction GSI-C2, Explosive Atmospheres (en); General Safety Instruction GSI-C3, Monitoring of Exposure to Hazardous Chemical Agents in Workplace Atmospheres (en). These documents form part of the CERN Safety Rules and are issued in application of the “Staff Rules and Regulations” and of document SAPOCO 42. These documents set out the minimum requirements for the protection of persons from risks to their occupational safety and health arising, or likely to arise, from the effects of hazardous chemical agents that are present in the workplace or used in any CERN activity. Simultaneously, the HSE Unit has published seven Safety Guidelines and six Safety Forms. These documents are available from the dedicated Web page “Chemical, Cryogenic and Biological Safety&...

Genetics Home Reference: bladder cancer

Science.gov (United States)

... Testing Registry: Malignant tumor of urinary bladder Other Diagnosis and Management Resources (1 link) MedlinePlus Encyclopedia: Bladder Cancer General Information from MedlinePlus (5 links) Diagnostic Tests ...

Traumatic Brain Injury: MedlinePlus Health Topic

Science.gov (United States)

... injury - discharge (Medical Encyclopedia) Also in Spanish Chronic subdural hematoma (Medical Encyclopedia) Also in Spanish EEG (Medical Encyclopedia) ... Intracranial pressure monitoring (Medical Encyclopedia) Also in Spanish Subdural hematoma (Medical Encyclopedia) Also in Spanish Topic Image MedlinePlus ...

Chemical warfare agents

Directory of Open Access Journals (Sweden)

Vijayaraghavan R

2010-01-01

Full Text Available Among the Weapons of Mass Destruction, chemical warfare (CW is probably one of the most brutal created by mankind in comparison with biological and nuclear warfare. Chemical weapons are inexpensive and are relatively easy to produce, even by small terrorist groups, to create mass casualties with small quantities. The characteristics of various CW agents, general information relevant to current physical as well as medical protection methods, detection equipment available and decontamination techniques are discussed in this review article. A brief note on Chemical Weapons Convention is also provided.

Chemical warfare agents

Science.gov (United States)

Ganesan, K.; Raza, S. K.; Vijayaraghavan, R.

2010-01-01

Among the Weapons of Mass Destruction, chemical warfare (CW) is probably one of the most brutal created by mankind in comparison with biological and nuclear warfare. Chemical weapons are inexpensive and are relatively easy to produce, even by small terrorist groups, to create mass casualties with small quantities. The characteristics of various CW agents, general information relevant to current physical as well as medical protection methods, detection equipment available and decontamination techniques are discussed in this review article. A brief note on Chemical Weapons Convention is also provided. PMID:21829312

BOOK REVIEW: Introductory Nanoscience: Physical and Chemical Concepts Introductory Nanoscience: Physical and Chemical Concepts

Science.gov (United States)

Bich Ha, Nguyen

2011-12-01

Having grown rapidly during the last two decades, and successfully synthesized the achievements of physics, chemistry, life science as well as information and computational science and technology, nanoscience and nanotechnology have emerged as interdisciplinary fields of modern science and technology with various prospective applications towards environmental protection and the sustainable development of industry, agriculture, public health etc. At the present time, there exist many textbooks, monographs and encyclopedias on nanoscience and nanotechnology. They present to readers the whole process of development from the emergence of new scientific ideas to comprehensive studies of concrete subjects. They are useful for experienced scientists in nanoscience and nanotechnology as well as related scientific disciplines. However, there are very few textbooks on nanoscience and nanotechnology for beginners—senior undergraduate and junior graduate students. Published by Garland Science in August 2011, Introductory Nanoscience: Physical and Chemical Concepts by Masaru Kuno is one of these rare textbooks. The purpose of this book is twofold. In a pedagogical manner the author presents the basic physical and chemical concepts of nanoscience and nanotechnology. Students with a background knowledge in general chemistry and semiclassical quantum physics can easily understand these concepts. On the other hand, by carefully studying the content of this textbook, readers can learn how to derive a large number of formulae and expressions which they will often use in their study as well as in their future research work. A distinguishing feature of the book is the inclusion of a large number of thought problems at the end of each chapter for demonstrating how to calculate the numerical values of almost all physical quantities involved in the theoretical and experimental studies of all subjects of nanoscience and nanotechnology. The author has successfully achieved both of the

Chemical graph-theoretic cluster expansions

International Nuclear Information System (INIS)

Klein, D.J.

1986-01-01

A general computationally amenable chemico-graph-theoretic cluster expansion method is suggested as a paradigm for incorporation of chemical structure concepts in a systematic manner. The cluster expansion approach is presented in a formalism general enough to cover a variety of empirical, semiempirical, and even ab initio applications. Formally such approaches for the utilization of chemical structure-related concepts may be viewed as discrete analogues of Taylor series expansions. The efficacy of the chemical structure concepts then is simply bound up in the rate of convergence of the cluster expansions. In many empirical applications, e.g., boiling points, chromatographic separation coefficients, and biological activities, this rate of convergence has been observed to be quite rapid. More note will be made here of quantum chemical applications. Relations to questions concerning size extensivity of energies and size consistency of wave functions are addressed

Response Manual for Combating Spills of Floating Hazardous CHRIS chemicals

Science.gov (United States)

1989-01-01

NICKEL AMMONIUM SULFATE NAS No NICKEL BROMIDE NBR No NICKEL CARBONYL NKC No 3 NICKEL CHLORIDE NCL No NICKEL CYANIDE NCN No NICKEL FLUOBORATE NFB No...Neoprene Good Poor Poor Fair Good Good Nitrile Rubber Fair Fair Fair Good Good Good *Sources: Encyclopedia of Polymer Science and Engineering, 2nd Edition...two types. The first type consists of a rubber ball with a toggle bolt arranged so that it can be tightened to expand the rubber ball to fit the hole

Differences in the regulation of chemicals and radionuclides

International Nuclear Information System (INIS)

Travis, C.C.

1993-12-01

Government regulations limiting public exposure to radionuclides and chemicals have historically been developed by regulatory agencies using different approaches with the result that levels of protection vary for the two classes of contaminants. These differences create difficulties in determining equitable regulatory measures when both radionuclides and chemical pollutants are involved. Generally, radiation exposure is not regulated as stringently as chemical exposure (Travis et al, 1989). The International commission on Radiological Protection (ICRP) recommends limiting excess environmental radiation exposure to the general public to 100 millirem per year (mrem/yr) (ICRP, 1991), a lifetime cancer risk of about 3.5E-3. An acceptable level of risk for chemical exposures is generally considered to be below 1E-6. Differences in regulatory approach for radionuclides and chemicals evoke debate over why they are different and which regulation strategy is better. Because these pollutants often coexist (mixed waste sites, contaminated metals and facilities, etc.), it is important to analyze inconsistencies in the regulation of chemicals and radionuclides and establish a more consistent approach to defining an acceptable level of exposure for these contaminants

Dissipation, generalized free energy, and a self-consistent nonequilibrium thermodynamics of chemically driven open subsystems.

Science.gov (United States)

Ge, Hao; Qian, Hong

2013-06-01

Nonequilibrium thermodynamics of a system situated in a sustained environment with influx and efflux is usually treated as a subsystem in a larger, closed "universe." A question remains with regard to what the minimally required description for the surrounding of such an open driven system is so that its nonequilibrium thermodynamics can be established solely based on the internal stochastic kinetics. We provide a solution to this problem using insights from studies of molecular motors in a chemical nonequilibrium steady state (NESS) with sustained external drive through a regenerating system or in a quasisteady state (QSS) with an excess amount of adenosine triphosphate (ATP), adenosine diphosphate (ADP), and inorganic phosphate (Pi). We introduce the key notion of minimal work that is needed, W(min), for the external regenerating system to sustain a NESS (e.g., maintaining constant concentrations of ATP, ADP and Pi for a molecular motor). Using a Markov (master-equation) description of a motor protein, we illustrate that the NESS and QSS have identical kinetics as well as the second law in terms of the same positive entropy production rate. The heat dissipation of a NESS without mechanical output is exactly the W(min). This provides a justification for introducing an ideal external regenerating system and yields a free-energy balance equation between the net free-energy input F(in) and total dissipation F(dis) in an NESS: F(in) consists of chemical input minus mechanical output; F(dis) consists of dissipative heat, i.e. the amount of useful energy becoming heat, which also equals the NESS entropy production. Furthermore, we show that for nonstationary systems, the F(dis) and F(in) correspond to the entropy production rate and housekeeping heat in stochastic thermodynamics and identify a relative entropy H as a generalized free energy. We reach a new formulation of Markovian nonequilibrium thermodynamics based on only the internal kinetic equation without further

Coupling chemical and biological catalysis: a flexible paradigm for producing biobased chemicals.

Science.gov (United States)

Schwartz, Thomas J; Shanks, Brent H; Dumesic, James A

2016-04-01

Advances in metabolic engineering have allowed for the development of new biological catalysts capable of selectively de-functionalizing biomass to yield platform molecules that can be upgraded to biobased chemicals using high efficiency continuous processing allowed by heterogeneous chemical catalysis. Coupling these disciplines overcomes the difficulties of selectively activating COH bonds by heterogeneous chemical catalysis and producing petroleum analogues by biological catalysis. We show that carboxylic acids, pyrones, and alcohols are highly flexible platforms that can be used to produce biobased chemicals by this approach. More generally, we suggest that molecules with three distinct functionalities may represent a practical upper limit on the extent of functionality present in the platform molecules that serve as the bridge between biological and chemical catalysis. Copyright © 2016 Elsevier Ltd. All rights reserved.

Genetics Home Reference: familial isolated pituitary adenoma

Science.gov (United States)

... children or adolescents can lead to increased height (gigantism), because the long bones of their arms and ... Information & Resources MedlinePlus (6 links) Encyclopedia: Acromegaly Encyclopedia: Gigantism Encyclopedia: Pituitary Tumor Encyclopedia: Prolactinoma Health Topic: Endocrine ...

XIX Mendeleev Congress on general and applied chemistry. Abstract book in 4 volumes. Volume 4. Chemistry aspects of modern energy and alternative energy resources. Chemistry of fossil and renewable hydrocarbon raw materials. Analytical chemistry: novel methods and devices for chemical research and analysis. Chemical education

International Nuclear Information System (INIS)

2011-01-01

The abstracts of the XIX Mendeleev Congress on general and applied chemistry held 25-30 September 2011 in Volgograd are presented. The program includes the Congress plenary and section reports, poster presentations, symposia and round tables on key areas of chemical science and technology, and chemical education. The work of the Congress was held the following sections: 1. Fundamental problems of chemical sciences; 2. Chemistry and technology of materials, including nanomaterials; 3. Physicochemical basis of metallurgical processes; 4. Current issues of chemical production, technical risk assessment; 5. Chemical aspects of modern power and alternative energy sources; 6. Chemistry of fossil and renewable hydrocarbons; 7. Analytical chemistry: new methods and instruments for chemical research and analysis; 8. Chemical education. Volume 4 includes abstracts of oral and poster presentations and presentations of correspondent participants of the sections: Chemistry aspects of modern energy and alternative energy resources; Chemistry of fossil and renewable hydrocarbon raw materials; Analytical chemistry: novel methods and devices for chemical research and analysis; Chemical education, and author index [ru

Genetics Home Reference: familial partial lipodystrophy

Science.gov (United States)

... an abnormal buildup of fats in the liver (hepatic steatosis), which can result in an enlarged liver (hepatomegaly) ... Encyclopedia: Chronic Pancreatitis Encyclopedia: Coronary Heart Disease Encyclopedia: Fatty Liver - Nonalcoholic Encyclopedia: Polycystic Ovary Disease Health Topic: Coronary ...

[New approaches to early diagnosis of chronic organophosphorus chemicals intoxication in workers at chemical weapons extermination objects].

Science.gov (United States)

Babakov, V N; Goncharov, N V; Radilov, A S; Glashkina, E P; Podol'skaia, E P; Ermolaeva, E E; Shilov, V V; Prokof'eva, D S; Voĭtenko, N G; Egorov, N A

2009-01-01

Mass spectrum analysis revealed differences in general contents of low-molecular peptides spectrums in chemical weapons extermination object staffers, in comparison with the reference group. Findings are that serum paraoxonase activity in chemical weapons extermination object staffers in significantly increased.

Genetics Home Reference: chylomicron retention disease

Science.gov (United States)

... reflexes (hyporeflexia) and a decreased ability to feel vibrations. Related Information What does it mean if a ... Encyclopedia: Malabsorption General Information from MedlinePlus (5 links) Diagnostic Tests Drug Therapy Genetic Counseling Palliative Care Surgery ...

Genetics Home Reference: hereditary diffuse gastric cancer

Science.gov (United States)

... Health Conditions Hereditary diffuse gastric cancer Hereditary diffuse gastric cancer Printable PDF Open All Close All Enable Javascript ... Diffuse Gastric Cancer MedlinePlus Encyclopedia: Gastric Cancer National Cancer ... Option Overview General Information from MedlinePlus ( ...

Genetics Home Reference: platyspondylic lethal skeletal dysplasia, Torrance type

Science.gov (United States)

... and an exaggerated curvature of the lower back ( lordosis ). Infants with this condition are born with a ... Diagnosis and Management Resources (1 link) MedlinePlus Encyclopedia: Lordosis General Information from MedlinePlus (5 links) Diagnostic Tests ...

40 CFR 68.12 - General requirements.

Science.gov (United States)

2010-07-01

...) CHEMICAL ACCIDENT PREVENTION PROVISIONS General § 68.12 General requirements. (a) General requirements. The... the five-year accident history for the process as provided in § 68.42 of this part and submit it in... §§ 68.150 to 68.185. The RMP shall include a registration that reflects all covered processes. (b...

Toxicity testing of chemical mixtures: some general aspects and need of international guidelines.

Science.gov (United States)

Kappus, H; Yang, R S

1996-01-01

The topics discussed by the Working Group on Toxicity Testing of Chemical Mixtures included the following (1) the study designs and results from two real-life exposure scenarios as additional information to the various investigations reported at the conference; (2) the need to take into consideration low-level, long-term exposure (i.e. mimicking human exposure conditions) as well as the issue of limited resources in experimental toxicology studies; (3) the importance of exploring alternative and predictive toxicology methodologies to minimize animal use and to conserve resources; (4) the realization that interactive toxicity should include the consideration of physical and biological agents in addition to chemicals. Two specific studies reported at the conference were also discussed. A number of recommendations were made concerning the planning and implementation of toxicology studies on chemical mixtures.

Genetics Home Reference: Manitoba oculotrichoanal syndrome

Science.gov (United States)

... opening in the wall of the abdomen (an omphalocele ) that allows the abdominal organs to protrude through ... 2 links) GeneReview: Manitoba Oculotrichoanal Syndrome MedlinePlus Encyclopedia: Omphalocele Repair General Information from MedlinePlus (5 links) Diagnostic ...

Genetics Home Reference: hypophosphatasia

Science.gov (United States)

... by a softening of the bones known as osteomalacia. In adults, recurrent fractures in the foot and ... Management Resources (2 links) GeneReview: Hypophosphatasia MedlinePlus Encyclopedia: Osteomalacia General Information from MedlinePlus (5 links) Diagnostic Tests ...

Computing Properties Of Chemical Mixtures At Equilibrium

Science.gov (United States)

Mcbride, B. J.; Gordon, S.

1995-01-01

Scientists and engineers need data on chemical equilibrium compositions to calculate theoretical thermodynamic properties of chemical systems. Information essential in design and analysis of such equipment as compressors, turbines, nozzles, engines, shock tubes, heat exchangers, and chemical-processing equipment. CET93 is general program that calculates chemical equilibrium compositions and properties of mixtures for any chemical system for which thermodynamic data are available. Includes thermodynamic data for more than 1,300 gaseous and condensed species and thermal-transport data for 151 gases. Written in FORTRAN 77.

Thermodynamic chemical energy transfer mechanisms of non-equilibrium, quasi-equilibrium, and equilibrium chemical reactions

International Nuclear Information System (INIS)

Roh, Heui-Seol

2015-01-01

Chemical energy transfer mechanisms at finite temperature are explored by a chemical energy transfer theory which is capable of investigating various chemical mechanisms of non-equilibrium, quasi-equilibrium, and equilibrium. Gibbs energy fluxes are obtained as a function of chemical potential, time, and displacement. Diffusion, convection, internal convection, and internal equilibrium chemical energy fluxes are demonstrated. The theory reveals that there are chemical energy flux gaps and broken discrete symmetries at the activation chemical potential, time, and displacement. The statistical, thermodynamic theory is the unification of diffusion and internal convection chemical reactions which reduces to the non-equilibrium generalization beyond the quasi-equilibrium theories of migration and diffusion processes. The relationship between kinetic theories of chemical and electrochemical reactions is also explored. The theory is applied to explore non-equilibrium chemical reactions as an illustration. Three variable separation constants indicate particle number constants and play key roles in describing the distinct chemical reaction mechanisms. The kinetics of chemical energy transfer accounts for the four control mechanisms of chemical reactions such as activation, concentration, transition, and film chemical reactions. - Highlights: • Chemical energy transfer theory is proposed for non-, quasi-, and equilibrium. • Gibbs energy fluxes are expressed by chemical potential, time, and displacement. • Relationship between chemical and electrochemical reactions is discussed. • Theory is applied to explore nonequilibrium energy transfer in chemical reactions. • Kinetics of non-equilibrium chemical reactions shows the four control mechanisms

46 CFR 154.1170 - Hand hose line: General.

Science.gov (United States)

2010-10-01

... STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Firefighting System: Dry Chemical § 154.1170 Hand hose line: General. Each dry chemical hand hose line must: (a...

Chemical evolutionary games.

Science.gov (United States)

Aristotelous, Andreas C; Durrett, Richard

2014-05-01

Inspired by the use of hybrid cellular automata in modeling cancer, we introduce a generalization of evolutionary games in which cells produce and absorb chemicals, and the chemical concentrations dictate the death rates of cells and their fitnesses. Our long term aim is to understand how the details of the interactions in a system with n species and m chemicals translate into the qualitative behavior of the system. Here, we study two simple 2×2 games with two chemicals and revisit the two and three species versions of the one chemical colicin system studied earlier by Durrett and Levin (1997). We find that in the 2×2 examples, the behavior of our new spatial model can be predicted from that of the mean field differential equation using ideas of Durrett and Levin (1994). However, in the three species colicin model, the system with diffusion does not have the coexistence which occurs in the lattices model in which sites interact with only their nearest neighbors. Copyright © 2014 Elsevier Inc. All rights reserved.

SAW Sensors for Chemical Vapors and Gases.

Science.gov (United States)

Devkota, Jagannath; Ohodnicki, Paul R; Greve, David W

2017-04-08

Surface acoustic wave (SAW) technology provides a sensitive platform for sensing chemicals in gaseous and fluidic states with the inherent advantages of passive and wireless operation. In this review, we provide a general overview on the fundamental aspects and some major advances of Rayleigh wave-based SAW sensors in sensing chemicals in a gaseous phase. In particular, we review the progress in general understanding of the SAW chemical sensing mechanism, optimization of the sensor characteristics, and the development of the sensors operational at different conditions. Based on previous publications, we suggest some appropriate sensing approaches for particular applications and identify new opportunities and needs for additional research in this area moving into the future.

SAW Sensors for Chemical Vapors and Gases

Science.gov (United States)

Devkota, Jagannath; Ohodnicki, Paul R.; Greve, David W.

2017-01-01

Surface acoustic wave (SAW) technology provides a sensitive platform for sensing chemicals in gaseous and fluidic states with the inherent advantages of passive and wireless operation. In this review, we provide a general overview on the fundamental aspects and some major advances of Rayleigh wave-based SAW sensors in sensing chemicals in a gaseous phase. In particular, we review the progress in general understanding of the SAW chemical sensing mechanism, optimization of the sensor characteristics, and the development of the sensors operational at different conditions. Based on previous publications, we suggest some appropriate sensing approaches for particular applications and identify new opportunities and needs for additional research in this area moving into the future. PMID:28397760

Virtual Pediatric Hospital

Science.gov (United States)

... Thoracopaedia - An Imaging Encyclopedia of Pediatric Thoracic Disease Virtual Pediatric Hospital is the Apprentice's Assistant™ Last revised ... pediatric resources: GeneralPediatrics.com | PediatricEducation.org | SearchingPediatrics.com Virtual Pediatric Hospital is curated by Donna M. D' ...

The General Safety Group Annual Report 2001/2002

CERN Document Server

Weingarten, W

2003-01-01

This report summarizes the main activities of the General Safety (GS) Group of the Technical Inspection and Safety Division during 2001 and 2002, and the results obtained. The different topics in which the group is active are covered: general safety inspections and ergonomics, electrical, chemical and gas safety, chemical pollution containment and control, industrial hygiene, the safety of civil engineering works and outside contractors, fire prevention and the safety aspects of the LHC experiments.

Chemical reaction due to stronger Ramachandran interaction

Indian Academy of Sciences (India)

actions between two polarized atoms are responsible for initiating a chemical reaction, either before or after ... Chemical reaction; Ramachandran interaction; anisotropic and asymmetric polarization; ionization ..... man sequence exactly, including the generalized mech- ..... We now move on and rearrange Eq. (8) to arrive at.

40 CFR 425.02 - General definitions.

Science.gov (United States)

2010-07-01

... STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE CATEGORY General Provisions § 425.02 General...) “Chrome tan” means the process of converting hide into leather using a form of chromium. (g) “Vegetable tan” means the process of converting hides into leather using chemicals either derived from vegetable...

Job Relocation is High in Chemical Industry.

Science.gov (United States)

Chemical and Engineering News, 1979

1979-01-01

The chances of an employee being relocated are higher in the chemical and plastics industries than in U.S. business as a whole. But the benefits provided by chemical and plastics companies to employees shifted to other locations are generally better than average. (Author/BB)

Genetics Home Reference: Rett syndrome

Science.gov (United States)

... Genetic Testing Registry: Rett syndrome Other Diagnosis and Management Resources (4 links) Boston Children's Hospital GeneReview: MECP2-Related Disorders MedlinePlus Encyclopedia: Rett Syndrome RettSyndrome.org: Rett Syndrome Clinics General Information from MedlinePlus (5 links) Diagnostic Tests ...

General multi-group macroscopic modeling for thermo-chemical non-equilibrium gas mixtures

Energy Technology Data Exchange (ETDEWEB)

Liu, Yen, E-mail: yen.liu@nasa.gov; Vinokur, Marcel [NASA Ames Research Center, Moffett Field, California 94035 (United States); Panesi, Marco; Sahai, Amal [University of Illinois, Urbana-Champaign, Illinois 61801 (United States)

2015-04-07

This paper opens a new door to macroscopic modeling for thermal and chemical non-equilibrium. In a game-changing approach, we discard conventional theories and practices stemming from the separation of internal energy modes and the Landau-Teller relaxation equation. Instead, we solve the fundamental microscopic equations in their moment forms but seek only optimum representations for the microscopic state distribution function that provides converged and time accurate solutions for certain macroscopic quantities at all times. The modeling makes no ad hoc assumptions or simplifications at the microscopic level and includes all possible collisional and radiative processes; it therefore retains all non-equilibrium fluid physics. We formulate the thermal and chemical non-equilibrium macroscopic equations and rate coefficients in a coupled and unified fashion for gases undergoing completely general transitions. All collisional partners can have internal structures and can change their internal energy states after transitions. The model is based on the reconstruction of the state distribution function. The internal energy space is subdivided into multiple groups in order to better describe non-equilibrium state distributions. The logarithm of the distribution function in each group is expressed as a power series in internal energy based on the maximum entropy principle. The method of weighted residuals is applied to the microscopic equations to obtain macroscopic moment equations and rate coefficients succinctly to any order. The model’s accuracy depends only on the assumed expression of the state distribution function and the number of groups used and can be self-checked for accuracy and convergence. We show that the macroscopic internal energy transfer, similar to mass and momentum transfers, occurs through nonlinear collisional processes and is not a simple relaxation process described by, e.g., the Landau-Teller equation. Unlike the classical vibrational energy

General multi-group macroscopic modeling for thermo-chemical non-equilibrium gas mixtures

Science.gov (United States)

Liu, Yen; Panesi, Marco; Sahai, Amal; Vinokur, Marcel

2015-04-01

This paper opens a new door to macroscopic modeling for thermal and chemical non-equilibrium. In a game-changing approach, we discard conventional theories and practices stemming from the separation of internal energy modes and the Landau-Teller relaxation equation. Instead, we solve the fundamental microscopic equations in their moment forms but seek only optimum representations for the microscopic state distribution function that provides converged and time accurate solutions for certain macroscopic quantities at all times. The modeling makes no ad hoc assumptions or simplifications at the microscopic level and includes all possible collisional and radiative processes; it therefore retains all non-equilibrium fluid physics. We formulate the thermal and chemical non-equilibrium macroscopic equations and rate coefficients in a coupled and unified fashion for gases undergoing completely general transitions. All collisional partners can have internal structures and can change their internal energy states after transitions. The model is based on the reconstruction of the state distribution function. The internal energy space is subdivided into multiple groups in order to better describe non-equilibrium state distributions. The logarithm of the distribution function in each group is expressed as a power series in internal energy based on the maximum entropy principle. The method of weighted residuals is applied to the microscopic equations to obtain macroscopic moment equations and rate coefficients succinctly to any order. The model's accuracy depends only on the assumed expression of the state distribution function and the number of groups used and can be self-checked for accuracy and convergence. We show that the macroscopic internal energy transfer, similar to mass and momentum transfers, occurs through nonlinear collisional processes and is not a simple relaxation process described by, e.g., the Landau-Teller equation. Unlike the classical vibrational energy

General multi-group macroscopic modeling for thermo-chemical non-equilibrium gas mixtures.

Science.gov (United States)

Liu, Yen; Panesi, Marco; Sahai, Amal; Vinokur, Marcel

2015-04-07

This paper opens a new door to macroscopic modeling for thermal and chemical non-equilibrium. In a game-changing approach, we discard conventional theories and practices stemming from the separation of internal energy modes and the Landau-Teller relaxation equation. Instead, we solve the fundamental microscopic equations in their moment forms but seek only optimum representations for the microscopic state distribution function that provides converged and time accurate solutions for certain macroscopic quantities at all times. The modeling makes no ad hoc assumptions or simplifications at the microscopic level and includes all possible collisional and radiative processes; it therefore retains all non-equilibrium fluid physics. We formulate the thermal and chemical non-equilibrium macroscopic equations and rate coefficients in a coupled and unified fashion for gases undergoing completely general transitions. All collisional partners can have internal structures and can change their internal energy states after transitions. The model is based on the reconstruction of the state distribution function. The internal energy space is subdivided into multiple groups in order to better describe non-equilibrium state distributions. The logarithm of the distribution function in each group is expressed as a power series in internal energy based on the maximum entropy principle. The method of weighted residuals is applied to the microscopic equations to obtain macroscopic moment equations and rate coefficients succinctly to any order. The model's accuracy depends only on the assumed expression of the state distribution function and the number of groups used and can be self-checked for accuracy and convergence. We show that the macroscopic internal energy transfer, similar to mass and momentum transfers, occurs through nonlinear collisional processes and is not a simple relaxation process described by, e.g., the Landau-Teller equation. Unlike the classical vibrational energy

General multi-group macroscopic modeling for thermo-chemical non-equilibrium gas mixtures

International Nuclear Information System (INIS)

Liu, Yen; Vinokur, Marcel; Panesi, Marco; Sahai, Amal

2015-01-01

This paper opens a new door to macroscopic modeling for thermal and chemical non-equilibrium. In a game-changing approach, we discard conventional theories and practices stemming from the separation of internal energy modes and the Landau-Teller relaxation equation. Instead, we solve the fundamental microscopic equations in their moment forms but seek only optimum representations for the microscopic state distribution function that provides converged and time accurate solutions for certain macroscopic quantities at all times. The modeling makes no ad hoc assumptions or simplifications at the microscopic level and includes all possible collisional and radiative processes; it therefore retains all non-equilibrium fluid physics. We formulate the thermal and chemical non-equilibrium macroscopic equations and rate coefficients in a coupled and unified fashion for gases undergoing completely general transitions. All collisional partners can have internal structures and can change their internal energy states after transitions. The model is based on the reconstruction of the state distribution function. The internal energy space is subdivided into multiple groups in order to better describe non-equilibrium state distributions. The logarithm of the distribution function in each group is expressed as a power series in internal energy based on the maximum entropy principle. The method of weighted residuals is applied to the microscopic equations to obtain macroscopic moment equations and rate coefficients succinctly to any order. The model’s accuracy depends only on the assumed expression of the state distribution function and the number of groups used and can be self-checked for accuracy and convergence. We show that the macroscopic internal energy transfer, similar to mass and momentum transfers, occurs through nonlinear collisional processes and is not a simple relaxation process described by, e.g., the Landau-Teller equation. Unlike the classical vibrational energy

Multiple Chemical Sensitivity

DEFF Research Database (Denmark)

Dantoft, Thomas Meinertz

Multiple chemical sensitivity (MCS) is a chronic disorder characterized by reports of symptoms from various organ systems attributed by the individuals to exposure to common odors and airborne chemicals in doses far below those known to induce toxic effects. There exists a general lack of knowledge......, significantly reduced levels of IL-13 in the MCS group and no group differences in the allergen specific IgE measures. The differences were independent of factors such as sex, age, Body Mass Index, asthma, smoking, depression, anxiety and allergen-specific IgE. In conclusion, the study identified a distinct...

Selected readings in chemical kinetics

CERN Document Server

Back, Margaret H

2013-01-01

Selected Readings in Chemical Kinetics covers excerpts from 12 papers in the field of general and gas-phase kinetics. The book discusses papers on the laws of connexion between the conditions of a chemical change and its amount; on the reaction velocity of the inversion of the cane sugar by acids; and the calculation in absolute measure of velocity constants and equilibrium constants in gaseous systems. The text then tackles papers on simple gas reactions; on the absolute rate of reactions in condensed phases; on the radiation theory of chemical action; and on the theory of unimolecular reacti

The chemical industry of Ukraine

International Nuclear Information System (INIS)

Novikov, I.N.

1995-01-01

This work deals with the chemical industry of Ukraine and more particularly with the restructuring proposed by the Ministry of Industry. After having presented some generalities the author focuses on the restructuring programme which includes the improvement of the fertilizers supply for agriculture, the development of facilities for basic organic synthesis, the increase of petroleum based chemicals production, the increase of consumer products production and the reorientation of the chemical industry to more accessible and alternative sources of raw materials such as black and brown coal, oil shale, coke, oil-refining gases, plant raw materials... (O.L.)

Odor concentration invariance by chemical ratio coding

Directory of Open Access Journals (Sweden)

Naoshige Uchida

2008-08-01

Full Text Available Many animal species rely on chemical signals to extract ecologically important information from the environment. Yet in natural conditions chemical signals will frequently undergo concentration changes that produce differences in both level and pattern of activation of olfactory receptor neurons. Thus, a central problem in olfactory processing is how the system is able to recognize the same stimulus across different concentrations. To signal species identity for mate recognition, some insects use the ratio of two components in a binary chemical mixture to produce a code that is invariant to dilution. Here, using psychophysical methods, we show that rats also classify binary odor mixtures according to the molar ratios of their components, spontaneously generalizing over at least a tenfold concentration range. These results indicate that extracting chemical ratio information is not restricted to pheromone signaling and suggest a general solution for concentration-invariant odor recognition by the mammalian olfactory system.

Job insecurity , work-based support, job satisfaction, organisational commitment and general health of human resources professionals in a chemical industry / by Florence Nomhlangano Rani

OpenAIRE

Rani, Nomhlangano Florence

2005-01-01

The work environment in which South African employees have to function is highly demanding, offering them little in terms of job security, but simultaneously expecting them to give more in terms of inter alia flexibility, competency, and effort. Tracking and addressing chemical industry employees' functioning in areas that could affect their general health and consequent standard of service is essential. Job insecurity, work-based support, job satisfaction, organisational commitment and gener...

A mini-encyclopedia of nuclear energy

International Nuclear Information System (INIS)

Istenic, Radko; Stritar, Andrej

2002-01-01

Atlas of Nuclear Technology is a central publication for the public information activities of the Nuclear Society of Slovenia. We started inviting schoolchildren, students and general public to lectures about radioactivity and nuclear technology already in 1993. Since that time we published many information-nation materials in Slovenian language for our visitors and updated the technical content of the Information-nation Centre several times. After a few years we realized how important it would be that every visitor would leave the Information Centre with some lasting interesting and easily understandable information in a single booklet. Therefore we updated and compiled all the available information panels from the Information Centre, separate leaflets and view-graphs from the lectures and added some essential text that is easily understood also by non-technical persons. From the very beginning we decided that there would be a lot of illustrations and that the text would be in Slovenian and English language in parallel. What finally emerged was a booklet of 60 pages, which we call 'Atlas of Nuclear Technology'. Contents include chapters on physics, TRIGA research reactor, Slovenian energy production, greenhouse effect, nuclear energy in the world, Krsko nuclear power plant, radioactive waste and nuclear accidents. Some 10 000 booklets were printed and are being distributed to the visitors. We refer to the Atlas during the lectures that are typically attended by 50 - 60 8-graders (up to 8000 per year) accompanied by several teachers. The response is very favorable. We get a lot of positive feedback and samples of posters that the schoolchildren have prepared as their homework using the Atlas as the main source of information. Also our yearly poll shows a steady good acceptance of nuclear energy among the youngsters. (author)

Is ionizing radiation regulated more stringently than chemical carcinogens

International Nuclear Information System (INIS)

Travis, C.C.; Pack, S.R.; Hattemer-Frey, H.A.

1989-01-01

It is widely believed that United States government agencies regulate exposure to ionizing radiation more stringently than exposure to chemical carcinogens. It is difficult to verify this perception, however, because chemical carcinogens and ionizing radiation are regulated using vastly different strategies. Chemical carcinogens are generally regulated individually. Regulators consider the risk of exposure to one chemical rather than the cumulative radiation exposure from all sources. Moreover, standards for chemical carcinogens are generally set in terms of quantities released or resultant environmental concentrations, while standards for ionizing radiation are set in terms of dose to the human body. Since chemicals and ionizing radiation cannot be compared on the basis of equal dose to the exposed individual, standards regulating chemicals and ionizing radiation cannot be compared directly. It is feasible, however, to compare the two sets of standards on the basis of equal risk to the exposed individual, assuming that standards for chemicals and ionizing radiation are equivalent if estimated risk levels are equitable. This paper compares risk levels associated with current standards for ionizing radiation and chemical carcinogens. The authors do not attempt to determine whether either type of risk is regulated too stringently or not stringently enough but endeavor only to ascertain if ionizing radiation is actually regulated more strictly than chemical carcinogens

Chemical process safety at fuel cycle facilities

International Nuclear Information System (INIS)

Ayres, D.A.

1997-08-01

This NUREG provides broad guidance on chemical safety issues relevant to fuel cycle facilities. It describes an approach acceptable to the NRC staff, with examples that are not exhaustive, for addressing chemical process safety in the safe storage, handling, and processing of licensed nuclear material. It expounds to license holders and applicants a general philosophy of the role of chemical process safety with respect to NRC-licensed materials; sets forth the basic information needed to properly evaluate chemical process safety; and describes plausible methods of identifying and evaluating chemical hazards and assessing the adequacy of the chemical safety of the proposed equipment and facilities. Examples of equipment and methods commonly used to prevent and/or mitigate the consequences of chemical incidents are discussed in this document

Testing and evaluation of eight decontamination chemicals

International Nuclear Information System (INIS)

Demmer, R.

1994-09-01

This report covers experimental work comparing eight different decontamination chemicals. Seven of these chemicals have some novelty, or are not currently in use at the ICPP. The eighth is a common ICPP decontamination reagent used as a baseline for effective comparison. Decontamination factors, waste generation values, and corrosion rates are tabulated for these chemicals. Recommendations are given for effective methods of non-sodium or low-sodium decontamination chemicals. The two most effective chemical for decontamination found in these test were a dilute hydrofluoric and nitric acid (HF/HNO 3 ) mixture and a fluoroboric acid solution. The fluoroboric acid solution (1 molar) was by far the most effective decontamination reagent, but suffered the problem of generating significant final calcine volume. The HF/HNO 3 solution performed a very good decontamination of the SIMCON coupons while generating only small amounts of calcine volume. Concentration variables were also tested, and optimized for these two solutions. Several oxidation/reduction decon chemical systems were also tested. These systems were similar to the TURCO 4502 and TURCO 4521 solutions used for general decontamination at the ICPP. A low sodium alternative, nitric acid/potassium permanganate, to the ''high sodium'' TURCO 4502 was tested extensively, optimized and recommended for general ICPP use. A reductive chemical solution, oxalic acid/nitric acid was also shown to have significant advantages

Chemical Utilisation of CO

Indian Academy of Sciences (India)

Home; Journals; Resonance – Journal of Science Education; Volume 20; Issue 2. Chemical Utilisation of CO2: A Challenge for the Sustainable World. Dinesh Jagadeesan Bhaskar Joshi Prashant Parameswaran. General Article Volume 20 Issue 2 February 2015 pp 165-176 ...

Chemical Graph Transformation with Stereo-Information

DEFF Research Database (Denmark)

Andersen, Jakob Lykke; Flamm, Christoph; Merkle, Daniel

2017-01-01

Double Pushout graph transformation naturally facilitates the modelling of chemical reactions: labelled undirected graphs model molecules and direct derivations model chemical reactions. However, the most straightforward modelling approach ignores the relative placement of atoms and their neighbo......Double Pushout graph transformation naturally facilitates the modelling of chemical reactions: labelled undirected graphs model molecules and direct derivations model chemical reactions. However, the most straightforward modelling approach ignores the relative placement of atoms...... and their neighbours in space. Stereoisomers of chemical compounds thus cannot be distinguished, even though their chemical activity may differ substantially. In this contribution we propose an extended chemical graph transformation system with attributes that encode information about local geometry. The modelling...... of graph transformation, but we here propose a framework that also allows for partially specified stereoinformation. While there are several stereochemical configurations to be considered, we focus here on the tetrahedral molecular shape, and suggest general principles for how to treat all other chemically...

The Museum of Science and Industry Basic List of Children's Science Books 1973-1984.

Science.gov (United States)

Richter, Bernice; Wenzel, Duane

Children's science books are listed under these headings: animals; astronomy; aviation and space; biography; careers; earth sciences; encyclopedias and reference books; environment and conservation; fiction; general science; life sciences; marine life; mathematics and computer science; medical and health sciences; physics and chemistry; plant…

New Proposals for the Design of Integrated Online Wine Industry ...

African Journals Online (AJOL)

The specialised lexicographic treatment ofoenology and viticulture usually consists in the compiling of articles describing the language of wine in general language dictionaries, or presenting professional knowledge of wine in specialised multi-field dictionaries and encyclopedias. This treatment also encompasses the ...

Trends in Exposure to Chemicals in Personal Care and Consumer Products.

Science.gov (United States)

Calafat, Antonia M; Valentin-Blasini, Liza; Ye, Xiaoyun

2015-12-01

Synthetic organic chemicals can be used in personal care and consumer products. Data on potential human health effects of these chemicals are limited-sometimes even contradictory-but because several of these chemicals are toxic in experimental animals, alternative compounds are entering consumer markets. Nevertheless, limited information exists on consequent exposure trends to both the original chemicals and their replacements. Biomonitoring (measuring concentrations of chemicals or their metabolites in people) provides invaluable information for exposure assessment. We use phthalates and bisphenol A-known industrial chemicals-and organophosphate insecticides as case studies to show exposure trends to these chemicals and their replacements (e.g., other phthalates, non-phthalate plasticizers, various bisphenols, pyrethroid insecticides) among the US general population. We compare US trends to national trends from Canada and Germany. Exposure to the original compounds is still prevalent among these general populations, but exposures to alternative chemicals may be increasing.

New Proposals for the Design of Integrated Online Wine Industry Dictionaries

DEFF Research Database (Denmark)

Leroyer, Patrick

2013-01-01

Abstract: The specialised lexicographic treatment of oenology and viticulture usually consists in the compiling of articles describing the language of wine in general language dictionaries, or presenting professional knowledge of wine in specialised multi-field dictionaries and encyclopedias. Thi...... dictionaries should not stand alone, as they could benefit from a full integration with the websites of the wine industry, and consequently transform into genuine lexicographic information tools.......Abstract: The specialised lexicographic treatment of oenology and viticulture usually consists in the compiling of articles describing the language of wine in general language dictionaries, or presenting professional knowledge of wine in specialised multi-field dictionaries and encyclopedias....... This treatment also encompasses the terminological compilation of single field dictionaries describing the language and/or knowledge of wine. Lexicographically speaking, all this is but a fraction of the complete picture. Indeed, the specialised lexicography of oenology and viticulture is multifaceted and goes...

Combined chemical shift changes and amino acid specific chemical shift mapping of protein-protein interactions

Energy Technology Data Exchange (ETDEWEB)

Schumann, Frank H.; Riepl, Hubert [University of Regensburg, Institute of Biophysics and Physical Biochemistry (Germany); Maurer, Till [Boehringer Ingelheim Pharma GmbH and Co. KG, Analytical Sciences Department (Germany); Gronwald, Wolfram [University of Regensburg, Institute of Biophysics and Physical Biochemistry (Germany); Neidig, Klaus-Peter [Bruker BioSpin GmbH, Software Department (Germany); Kalbitzer, Hans Robert [University of Regensburg, Institute of Biophysics and Physical Biochemistry (Germany)], E-mail: hans-robert.kalbitzer@biologie.uni-regensburg.de

2007-12-15

Protein-protein interactions are often studied by chemical shift mapping using solution NMR spectroscopy. When heteronuclear data are available the interaction interface is usually predicted by combining the chemical shift changes of different nuclei to a single quantity, the combined chemical shift perturbation {delta}{delta}{sub comb}. In this paper different procedures (published and non-published) to calculate {delta}{delta}{sub comb} are examined that include a variety of different functional forms and weighting factors for each nucleus. The predictive power of all shift mapping methods depends on the magnitude of the overlap of the chemical shift distributions of interacting and non-interacting residues and the cut-off criterion used. In general, the quality of the prediction on the basis of chemical shift changes alone is rather unsatisfactory but the combination of chemical shift changes on the basis of the Hamming or the Euclidian distance can improve the result. The corrected standard deviation to zero of the combined chemical shift changes can provide a reasonable cut-off criterion. As we show combined chemical shifts can also be applied for a more reliable quantitative evaluation of titration data.

Genetics Home Reference: hypercholesterolemia

Science.gov (United States)

... Encyclopedia: Familial hypercholesterolemia Encyclopedia: High blood cholesterol and triglycerides Encyclopedia: Xanthoma Health Topic: Cholesterol Health Topic: High Cholesterol in Children and Teens Health Topic: Lipid Metabolism Disorders Genetic and Rare Diseases Information Center (1 ...

DYNSYL: a general-purpose dynamic simulator for chemical processes

International Nuclear Information System (INIS)

Patterson, G.K.; Rozsa, R.B.

1978-01-01

Lawrence Livermore Laboratory is conducting a safeguards program for the Nuclear Regulatory Commission. The goal of the Material Control Project of this program is to evaluate material control and accounting (MCA) methods in plants that handle special nuclear material (SNM). To this end we designed and implemented the dynamic chemical plant simulation program DYNSYL. This program can be used to generate process data or to provide estimates of process performance; it simulates both steady-state and dynamic behavior. The MCA methods that may have to be evaluated range from sophisticated on-line material trackers such as Kalman filter estimators, to relatively simple material balance procedures. This report describes the overall structure of DYNSYL and includes some example problems. The code is still in the experimental stage and revision is continuing

31 CFR 598.309 - Narcotic drug; controlled substance; listed chemical.

Science.gov (United States)

2010-07-01

...; listed chemical. 598.309 Section 598.309 Money and Finance: Treasury Regulations Relating to Money and... SANCTIONS REGULATIONS General Definitions § 598.309 Narcotic drug; controlled substance; listed chemical. The terms narcotic drug, controlled substance, and listed chemical have the meanings given those terms...

She Got Game! Women in Sports.

Science.gov (United States)

Ruffle, Kathy

2002-01-01

Focuses on library collection development in the area of women in sports. Discusses Title IX, selecting titles, and prominent publishers in the field; and includes an annotated bibliography that includes encyclopedias, history, athletes, how-to books, coaching, general sports, magazines, and Web sites. (LRW)

Summaries of FY 1993 research in the chemical sciences

Energy Technology Data Exchange (ETDEWEB)

1993-08-01

The summaries in photochemical and radiation sciences, chemical physics, atomic physics, chemical energy, separations and analysis, heavy element chemistry, chemical engineering sciences, and advanced battery technology are arranged according to national laboratories and offsite institutions. Small business innovation research projects are also listed. Special facilities supported wholly or partly by the Division of Chemical Sciences are described. Indexes are provided for selected topics of general interest, institutions, and investigators.

7 CFR 2902.37 - General purpose de-icers.

Science.gov (United States)

2010-01-01

... 7 Agriculture 15 2010-01-01 2010-01-01 false General purpose de-icers. 2902.37 Section 2902.37... Items § 2902.37 General purpose de-icers. (a) Definition. Chemical products (e.g., salt, fluids) that... preference for qualifying biobased general purpose de-icers. By that date, Federal agencies that have the...

Development of a global 1-D chemically radiatively coupled model and an introduction to the development of a chemically coupled General Circulation Model

International Nuclear Information System (INIS)

Akiyoshi, H.

1997-01-01

A global one-dimensional, chemically and radiatively coupled model has been developed. The basic concept of the coupled model, definition of globally averaged zenith angles, the formulation of the model chemistry, radiation, the coupled processes, and profiles and diurnal variations of temperature and chemical species at a normal steady state are presented. Furthermore, a suddenly doubled CO 2 experiment and a Pinatubo aerosol increase experiment were performed with the model. The time scales of variations in ozone and temperature in the lower stratosphere of the coupled system in the doubled CO 2 experiment was long, due to a feedback process among ultra violet radiation, O(1D), NO y , NO x , and O 3 . From the Pinatubo aerosol experiment, a delay of maximum ozone decrease from the maximum aerosol loading is shown and discussed. Developments of 3-D chemical models with coupled processes are briefly described, and the ozone distribution from the first version of the 3-D model are presented. Chemical model development in National Institute for Environmental Studies (NIES) are briefly described. (author)

The calculation of proton chemical shifts in hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Abraham, Raymond J [Liverpool Univ. (United Kingdom). Dept. of Chemistry

1994-12-31

Novel extension of the CHARGE3 semi-empirical calculation of the partial atomic charges in molecules are described which allow the accurate calculation of the proton chemical shifts of a variety of acyclic alkanes. This simple scheme predicts the proton chemical shifts of all the simple alkanes, cyclohexane and methyl cyclohexanes, norbornane, trans-decalin and trans perhydrophenanthrene, comprising a range of chemical shifts from 0.3 to 2.2 {delta} with the known substituent chemical shifts of other functional groups this could allow the general prediction of proton chemical shifts in a simple and useful format. (author) 13 refs., 2 figs.

Genetics Home Reference: Feingold syndrome

Science.gov (United States)

... Feingold syndrome include an unusually small head size ( microcephaly ), a small jaw ( micrognathia ), a narrow opening of ... Duodenal Atresia MedlinePlus Encyclopedia: Esophageal Atresia MedlinePlus Encyclopedia: Microcephaly MedlinePlus Encyclopedia: Webbing of the Fingers or Toes ...

Genetics Home Reference: glucose-6-phosphate dehydrogenase deficiency

Science.gov (United States)

... deficiency Encyclopedia: Glucose-6-phosphate dehydrogenase test Encyclopedia: Hemolytic anemia Encyclopedia: Newborn jaundice Health Topic: Anemia Health Topic: G6PD Deficiency Health Topic: Newborn Screening Genetic and Rare Diseases Information Center (1 link) Glucose-6-phosphate dehydrogenase ...

Chemical model reduction under uncertainty

KAUST Repository

Malpica Galassi, Riccardo; Valorani, Mauro; Najm, Habib N.; Safta, Cosmin; Khalil, Mohammad; Ciottoli, Pietro P.

2017-01-01

A general strategy for analysis and reduction of uncertain chemical kinetic models is presented, and its utility is illustrated in the context of ignition of hydrocarbon fuel–air mixtures. The strategy is based on a deterministic analysis

Physical and chemical data collected using bottle casts from the GENERAL SAN MARTIN in the Scotia Sea and Weddell Sea from 14 December 1963 to 11 January 1964 (NODC Accession 0000791)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Physical and chemical data were collected using bottle casts in the Scotia Sea and Weddell Sea from the GENERAL SAN MARTIN. Data were collected from 14 December 1963...

Chemical Hygiene and Safety Plan

Energy Technology Data Exchange (ETDEWEB)

Berkner, K.

1992-08-01

The objective of this Chemical Hygiene and Safety Plan (CHSP) is to provide specific guidance to all LBL employees and contractors who use hazardous chemicals. This Plan, when implemented, fulfills the requirements of both the Federal OSHA Laboratory Standard (29 CFR 1910.1450) for laboratory workers, and the Federal OSHA Hazard Communication Standard (29 CFR 1910.1200) for non-laboratory operations (e.g., shops). It sets forth safety procedures and describes how LBL employees are informed about the potential chemical hazards in their work areas so they can avoid harmful exposures and safeguard their health. Generally, communication of this Plan will occur through training and the Plan will serve as a the framework and reference guide for that training.

Legal Information Sources: An Annotated Bibliography.

Science.gov (United States)

Conner, Ronald C.

This 25-page annotated bibliography describes the legal reference materials in the special collection of a medium-sized public library. Sources are listed in 12 categories: cases, dictionaries, directories, encyclopedias, forms, references for the lay person, general, indexes, laws and legislation, legal research aids, periodicals, and specialized…

2011 EPA Pesticide General Permit (PGP)

Data.gov (United States)

U.S. Environmental Protection Agency — The 2011 EPA Pesticide General Permit (PGP) covers discharges of biological pesticides, and chemical pesticides that leave a residue, in areas where EPA is the NPDES...

Chemical Continuous Time Random Walks

Science.gov (United States)

Aquino, T.; Dentz, M.

2017-12-01

Traditional methods for modeling solute transport through heterogeneous media employ Eulerian schemes to solve for solute concentration. More recently, Lagrangian methods have removed the need for spatial discretization through the use of Monte Carlo implementations of Langevin equations for solute particle motions. While there have been recent advances in modeling chemically reactive transport with recourse to Lagrangian methods, these remain less developed than their Eulerian counterparts, and many open problems such as efficient convergence and reconstruction of the concentration field remain. We explore a different avenue and consider the question: In heterogeneous chemically reactive systems, is it possible to describe the evolution of macroscopic reactant concentrations without explicitly resolving the spatial transport? Traditional Kinetic Monte Carlo methods, such as the Gillespie algorithm, model chemical reactions as random walks in particle number space, without the introduction of spatial coordinates. The inter-reaction times are exponentially distributed under the assumption that the system is well mixed. In real systems, transport limitations lead to incomplete mixing and decreased reaction efficiency. We introduce an arbitrary inter-reaction time distribution, which may account for the impact of incomplete mixing. This process defines an inhomogeneous continuous time random walk in particle number space, from which we derive a generalized chemical Master equation and formulate a generalized Gillespie algorithm. We then determine the modified chemical rate laws for different inter-reaction time distributions. We trace Michaelis-Menten-type kinetics back to finite-mean delay times, and predict time-nonlocal macroscopic reaction kinetics as a consequence of broadly distributed delays. Non-Markovian kinetics exhibit weak ergodicity breaking and show key features of reactions under local non-equilibrium.

Sustainable Chemical Processes and Products. New Design Methodology and Design Tools

OpenAIRE

Korevaar, G.

2004-01-01

The current chemical industry is not sustainable, which leads to the fact that innovation of chemical processes and products is too often hazardous for society in general and the environment in particular. It really is a challenge to implement sustainability considerations in the design activities of chemical engineers. Therefore, the main question of this thesis is: how can a trained chemical engineer develop a conceptual design of a chemical process or a chemical product in such a way that ...

Chemical reactions in reverse micelle systems

Science.gov (United States)

Matson, Dean W.; Fulton, John L.; Smith, Richard D.; Consani, Keith A.

1993-08-24

This invention is directed to conducting chemical reactions in reverse micelle or microemulsion systems comprising a substantially discontinuous phase including a polar fluid, typically an aqueous fluid, and a microemulsion promoter, typically a surfactant, for facilitating the formation of reverse micelles in the system. The system further includes a substantially continuous phase including a non-polar or low-polarity fluid material which is a gas under standard temperature and pressure and has a critical density, and which is generally a water-insoluble fluid in a near critical or supercritical state. Thus, the microemulsion system is maintained at a pressure and temperature such that the density of the non-polar or low-polarity fluid exceeds the critical density thereof. The method of carrying out chemical reactions generally comprises forming a first reverse micelle system including an aqueous fluid including reverse micelles in a water-insoluble fluid in the supercritical state. Then, a first reactant is introduced into the first reverse micelle system, and a chemical reaction is carried out with the first reactant to form a reaction product. In general, the first reactant can be incorporated into, and the product formed in, the reverse micelles. A second reactant can also be incorporated in the first reverse micelle system which is capable of reacting with the first reactant to form a product.

Major national human biomonitoring programs in chemical exposure assessment

Directory of Open Access Journals (Sweden)

Judy Choi

2015-07-01

Full Text Available Human biomonitoring (HBM programs have been established in several countries around the world in order to monitor the levels of chemical exposures in the general population and qualify health risk assessment of national and international interest. Study design, population, sample collection, and chemical analysis must be considered when comparing and interpreting the results. In this review, the objectives and brief descriptions of the major national HBM programs in North America, Europe, and Asia are provided. Similarities and differences observed from a comparative analysis among these programs, including the stratification of data according to age, sex, socioeconomic background, etc. as well as the identification of chemical exposure associated with food intake, are discussed. Overall, although there are some discrepancies in the study designs among the reviewed national HBM programs, results from the programs can provide useful information such as chemical levels found within the general population of a country that can be compared. Furthermore, the results can be used by regulatory authorities or the government to enforce legislations in order to reduce the exposure of chemicals into the human body.

Encyclopedia of distances

CERN Document Server

Deza, Michel Marie

2014-01-01

This updated and revised third edition of the leading reference volume on distance metrics includes new items from very active research areas in the use of distances and metrics such as geometry, graph theory, probability theory and analysis. Among the new topics included are, for example, polyhedral metric space, nearness matrix problems, distances between belief assignments, distance-related animal settings, diamond-cutting distances, natural units of length, Heidegger’s de-severance distance, and brain distances. The publication of this volume coincides with intensifying research efforts into metric spaces and especially distance design for applications. Accurate metrics have become a crucial goal in computational biology, image analysis, speech recognition and information retrieval. Leaving aside the practical questions that arise during the selection of a ‘good’ distance function, this work focuses on providing the research community with an invaluable comprehensive listing of the main available di...

Two encyclopedia contributions

DEFF Research Database (Denmark)

Andersen, Per Kragh

2003-01-01

censoring; Cox regression model; counting process; event history analysis; intensity process; multi-state model; non-parametric inference; parametric models; survival analysis; Cox's proportional hazards model; hazard function, regression model; time-dependent covariate; time scale...

Encyclopedia of distances

CERN Document Server

Deza, Michel Marie

2009-01-01

Distance metrics and distances have become an essential tool in many areas of pure and applied Mathematics. This title offers both independent introductions and definitions, while at the same time making cross-referencing easy through hyperlink-like boldfaced references to original definitions.

An Introduction to the Law and Economics of Regulation

NARCIS (Netherlands)

A.M. Pacces (Alessio); R.J. van den Bergh (Roger)

2011-01-01

textabstractAbstract This chapter provides a general framework to analyze regulation with a law and economics approach. It introduces the volume “Regulation and Economics” of the second edition of the Encyclopedia of Law and Economics. This study intends to provide a state-of-the-art overview of

Fissuring-chemical damaging on transfers in concrete

International Nuclear Information System (INIS)

Tognazzi, C.

1998-01-01

Concrete is a material often use in the nuclear wastes disposal. The safety analysis of a long time wastes disposal with concrete requires to verify the concrete behaviour in water. As concretes generally have cracks, it is necessary to study the crack propagation influence on chemical degradation. In this paper, the author presents diffusion tests on fissured and/or chemical aged cement. The chemical degradation of the material leads to a supplementary porosity by the hydrates decalcification and increases its diffusivity. The cracking impact is less important and can be experimentally concealed. (A.L.B.)

Pesticides: chemicals for survival

International Nuclear Information System (INIS)

Lindquist, D.A.

1981-01-01

Pesticides are chemicals used to control pests such as insects, weeds, plant diseases, nematodes, and rodents. The increased use of pesticides since 1945 has greatly aided the increase in crop production, protected livestock from diseases such as trypanosomiasis, protected man from diseases such as malaria and filarisis, decreased losses of stored grain, and has generally improved man's welfare. Despite the enormous benefits derived from pesticides these chemicals are not problem-free. Many pesticides are toxic to living organisms and interfere with specific biochemical systems. To measure the very small quantities of a pesticide radiolabelled chemicals are frequently essential, particularly to measure changes in the chemical structure of the pesticide, movement of the pesticide in soil, plants, or animals, amounts of pesticide going through various steps in food processing, etc. The use of radiolabelled pesticides is shortly shown for metabolism of the pesticide in crop species, metabolism in ruminant, in chickens and eggs, in soil, and possibly leaching and sorption in soil, hydrolysis, bio-concentration, microbial and photodegradation, and toxicity studies

Contribution of chemical radiation research to the general theory of oxidation of organic substances

International Nuclear Information System (INIS)

Ladygin, B.Ya.; Saraev, V.V.; Revin, A.A.; Zimina, G.M.

1996-01-01

Paper studies mechanisms and main elementary stages of liquid-phase oxidation of organic compounds at thermal and radiation initiation of this reaction. The results of investigations into radiation and chemical conversion of organic compounds at presence of oxygen and without it are discussed on the ground of data obtained by means of pulse radiolysis and EPR-spectroscopy. The bach-Engler theory of slow oxidation of organic compounds with participation of peroxides used as intermediate compounds is shown to be proved essentially and to enjoy further development due to the conducted radiation and chemical investigations. 68 refs., 2 figs., 4 tabs

Chemical kinetics and reaction dynamics

CERN Document Server

Houston, Paul L

2006-01-01

This text teaches the principles underlying modern chemical kinetics in a clear, direct fashion, using several examples to enhance basic understanding. It features solutions to selected problems, with separate sections and appendices that cover more technical applications.Each chapter is self-contained and features an introduction that identifies its basic goals, their significance, and a general plan for their achievement. This text's important aims are to demonstrate that the basic kinetic principles are essential to the solution of modern chemical problems, and to show how the underlying qu

Chemical sensors are hybrid-input memristors

Science.gov (United States)

Sysoev, V. I.; Arkhipov, V. E.; Okotrub, A. V.; Pershin, Y. V.

2018-04-01

Memristors are two-terminal electronic devices whose resistance depends on the history of input signal (voltage or current). Here we demonstrate that the chemical gas sensors can be considered as memristors with a generalized (hybrid) input, namely, with the input consisting of the voltage, analyte concentrations and applied temperature. The concept of hybrid-input memristors is demonstrated experimentally using a single-walled carbon nanotubes chemical sensor. It is shown that with respect to the hybrid input, the sensor exhibits some features common with memristors such as the hysteretic input-output characteristics. This different perspective on chemical gas sensors may open new possibilities for smart sensor applications.

Journal of Chemical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Chemical Sciences. Sarat C Dash. Articles written in Journal of Chemical Sciences. Volume 123 Issue 4 July 2011 pp 497-507. Proximity effect on the general base catalysed hydrolysis of amide linkage: The role of cationic surfactant, CTABr · Sarat C Dash Anadi C Dash · More Details Abstract ...

Fuel and Chemicals from Renewable Alcohols

DEFF Research Database (Denmark)

Hansen, Jeppe Rass

2008-01-01

The present work entitled Fuel and Chemicals from Renewable Alcohols covers the idea of developing routes for producing sustainable fuel and chemicals from biomass resources. Some renewable alcohols are already readily available from biomass in significant amounts and thus the potential...... for these renewable alcohols, together with other primary renewable building blocks, has been highlighted in the introductory chapter. While the first chapter covers the general potential of a renewable chemical industry, the other chapters deal with particular possibilities. It is shown how ethanol and glycerol can...... be converted into hydrogen by steam reforming over nickel or ruthenium based catalysts. This process could be important in a future hydrogen society, where hydrogen can be utilized in high efficiency fuel cells. Hydrogen produced from biofeedstocks can also be used directly in the chemical industry, where...

Tools for chemical synthesis in microsystems

OpenAIRE

Jensen, Klavs F.; Newman, Stephen G.; Reizman, Brandon Jacob

2014-01-01

Chemical synthesis in microsystems has evolved from simple proof-of-principle examples to become a general technique in academia and industry. Numerous such “flow chemistry” applications are now found in pharmaceutical and fine chemical synthesis. Much of the development has been based on systems employing macroscopic flow components and tubes, rather than the integrated chip technology envisioned by the lab-on-a-chip community. We review the major developments in systems for flow chemistry a...

Revisiting the definition of the electronic chemical potential, chemical hardness, and softness at finite temperatures

International Nuclear Information System (INIS)

Franco-Pérez, Marco; Gázquez, José L.; Ayers, Paul W.; Vela, Alberto

2015-01-01

We extend the definition of the electronic chemical potential (μ e ) and chemical hardness (η e ) to finite temperatures by considering a reactive chemical species as a true open system to the exchange of electrons, working exclusively within the framework of the grand canonical ensemble. As in the zero temperature derivation of these descriptors, the response of a chemical reagent to electron-transfer is determined by the response of the (average) electronic energy of the system, and not by intrinsic thermodynamic properties like the chemical potential of the electron-reservoir which is, in general, different from the electronic chemical potential, μ e . Although the dependence of the electronic energy on electron number qualitatively resembles the piecewise-continuous straight-line profile for low electronic temperatures (up to ca. 5000 K), the introduction of the temperature as a free variable smoothens this profile, so that derivatives (of all orders) of the average electronic energy with respect to the average electron number exist and can be evaluated analytically. Assuming a three-state ensemble, well-known results for the electronic chemical potential at negative (−I), positive (−A), and zero values of the fractional charge (−(I + A)/2) are recovered. Similarly, in the zero temperature limit, the chemical hardness is formally expressed as a Dirac delta function in the particle number and satisfies the well-known reciprocity relation with the global softness

Philosophy of Interaction

DEFF Research Database (Denmark)

Svanæs, Dag

2011-01-01

This is an encyclopedia entry for the Interaction-Design.org free IxD encyclopedia. The topic of the entry is the application of the philosophy of Heidegger and Merleau-Ponty to a theory of interactivity. Comments by Don Norman and Eva Hornecker.......This is an encyclopedia entry for the Interaction-Design.org free IxD encyclopedia. The topic of the entry is the application of the philosophy of Heidegger and Merleau-Ponty to a theory of interactivity. Comments by Don Norman and Eva Hornecker....

PURE OR HYBRID? THE DEVELOPMENT OF MIXED DICTIONARY GENRES

OpenAIRE

Reinhard R. K. Hartmann

2005-01-01

This paper explores 'hybrid' genres of dictionaries and other reference works. Against the tradition of general dictionaries becoming ever more specialised, there has also been a growing trend of mixing two or more 'pure' dictionary types for achieving specific purposes, e.g. the combination of alphabetic and thematic dictionary,general dictionary and technical glossary, dictionary and thesaurus, dictionary and encyclopedia, monolingual and bilingual dictionary, etc. Examples of these various...

A general intermolecular force field based on tight-binding quantum chemical calculations

Science.gov (United States)

Grimme, Stefan; Bannwarth, Christoph; Caldeweyher, Eike; Pisarek, Jana; Hansen, Andreas

2017-10-01

A black-box type procedure is presented for the generation of a molecule-specific, intermolecular potential energy function. The method uses quantum chemical (QC) information from our recently published extended tight-binding semi-empirical scheme (GFN-xTB) and can treat non-covalently bound complexes and aggregates with almost arbitrary chemical structure. The necessary QC information consists of the equilibrium structure, Mulliken atomic charges, charge centers of localized molecular orbitals, and also of frontier orbitals and orbital energies. The molecular pair potential includes model density dependent Pauli repulsion, penetration, as well as point charge electrostatics, the newly developed D4 dispersion energy model, Drude oscillators for polarization, and a charge-transfer term. Only one element-specific and about 20 global empirical parameters are needed to cover systems with nuclear charges up to radon (Z = 86). The method is tested for standard small molecule interaction energy benchmark sets where it provides accurate intermolecular energies and equilibrium distances. Examples for structures with a few hundred atoms including charged systems demonstrate the versatility of the approach. The method is implemented in a stand-alone computer code which enables rigid-body, global minimum energy searches for molecular aggregation or alignment.

Production of chemicals and fuels from biomass

Energy Technology Data Exchange (ETDEWEB)

Woods, Elizabeth; Qiao, Ming; Myren, Paul; Cortright, Randy D.; Kania, John

2015-12-15

Described are methods, reactor systems, and catalysts for converting biomass to fuels and chemicals in a batch and/or continuous process. The process generally involves the conversion of water insoluble components of biomass, such as hemicellulose, cellulose and lignin, to volatile C.sub.2+O.sub.1-2 oxygenates, such as alcohols, ketones, cyclic ethers, esters, carboxylic acids, aldehydes, and mixtures thereof. In certain applications, the volatile C.sub.2+O.sub.1-2 oxygenates can be collected and used as a final chemical product, or used in downstream processes to produce liquid fuels, chemicals and other products.

Overall view of chemical and biochemical weapons.

Science.gov (United States)

Pitschmann, Vladimír

2014-06-04

This article describes a brief history of chemical warfare, which culminated in the signing of the Chemical Weapons Convention. It describes the current level of chemical weapons and the risk of using them. Furthermore, some traditional technology for the development of chemical weapons, such as increasing toxicity, methods of overcoming chemical protection, research on natural toxins or the introduction of binary technology, has been described. In accordance with many parameters, chemical weapons based on traditional technologies have achieved the limit of their development. There is, however, a big potential of their further development based on the most recent knowledge of modern scientific and technical disciplines, particularly at the boundary of chemistry and biology. The risk is even higher due to the fact that already, today, there is a general acceptance of the development of non-lethal chemical weapons at a technologically higher level. In the future, the chemical arsenal will be based on the accumulation of important information from the fields of chemical, biological and toxin weapons. Data banks obtained in this way will be hardly accessible and the risk of their materialization will persist.

Overall View of Chemical and Biochemical Weapons

Directory of Open Access Journals (Sweden)

Vladimír Pitschmann

2014-06-01

Full Text Available This article describes a brief history of chemical warfare, which culminated in the signing of the Chemical Weapons Convention. It describes the current level of chemical weapons and the risk of using them. Furthermore, some traditional technology for the development of chemical weapons, such as increasing toxicity, methods of overcoming chemical protection, research on natural toxins or the introduction of binary technology, has been described. In accordance with many parameters, chemical weapons based on traditional technologies have achieved the limit of their development. There is, however, a big potential of their further development based on the most recent knowledge of modern scientific and technical disciplines, particularly at the boundary of chemistry and biology. The risk is even higher due to the fact that already, today, there is a general acceptance of the development of non-lethal chemical weapons at a technologically higher level. In the future, the chemical arsenal will be based on the accumulation of important information from the fields of chemical, biological and toxin weapons. Data banks obtained in this way will be hardly accessible and the risk of their materialization will persist.

A Novel Approach for Modeling Chemical Reaction in Generalized Fluid System Simulation Program

Science.gov (United States)

Sozen, Mehmet; Majumdar, Alok

2002-01-01

The Generalized Fluid System Simulation Program (GFSSP) is a computer code developed at NASA Marshall Space Flight Center for analyzing steady state and transient flow rates, pressures, temperatures, and concentrations in a complex flow network. The code, which performs system level simulation, can handle compressible and incompressible flows as well as phase change and mixture thermodynamics. Thermodynamic and thermophysical property programs, GASP, WASP and GASPAK provide the necessary data for fluids such as helium, methane, neon, nitrogen, carbon monoxide, oxygen, argon, carbon dioxide, fluorine, hydrogen, water, a hydrogen, isobutane, butane, deuterium, ethane, ethylene, hydrogen sulfide, krypton, propane, xenon, several refrigerants, nitrogen trifluoride and ammonia. The program which was developed out of need for an easy to use system level simulation tool for complex flow networks, has been used for the following purposes to name a few: Space Shuttle Main Engine (SSME) High Pressure Oxidizer Turbopump Secondary Flow Circuits, Axial Thrust Balance of the Fastrac Engine Turbopump, Pressurized Propellant Feed System for the Propulsion Test Article at Stennis Space Center, X-34 Main Propulsion System, X-33 Reaction Control System and Thermal Protection System, and International Space Station Environmental Control and Life Support System design. There has been an increasing demand for implementing a combustion simulation capability into GFSSP in order to increase its system level simulation capability of a liquid rocket propulsion system starting from the propellant tanks up to the thruster nozzle for spacecraft as well as launch vehicles. The present work was undertaken for addressing this need. The chemical equilibrium equations derived from the second law of thermodynamics and the energy conservation equation derived from the first law of thermodynamics are solved simultaneously by a Newton-Raphson method. The numerical scheme was implemented as a User

Method of cleaning oil slicks and chemical spills

International Nuclear Information System (INIS)

Billings, L.

1992-01-01

This patent describes a method of cleaning a floating chemical spill on a body of water. It comprises: providing a quantity of popular bark-based pelleted or granular product, flotation means and a flexible net having openings generally smaller than the smallest whole pellet dimension of the pelleted product, spreading the net over a chemical spill on the body of water, connecting the floatation means to the net thereby supporting the net adjacent the surface of the body of water, placing the poplar bark-based product on the net, absorbing the floating chemical spill into the product, and removing the chemical soaked product from the body of water

Quality of life in chemical warfare survivors with ophthalmologic injuries: the first results form Iran Chemical Warfare Victims Health Assessment Study.

Science.gov (United States)

Mousavi, Batool; Soroush, Mohammad Reza; Montazeri, Ali

2009-01-19

Iraq used chemical weapons extensively against the Iranians during the Iran-Iraq war (1980-1988). The aim of this study was to assess the health related quality of life (HRQOL) in people who had ophthalmologic complications due to the sulfur mustard gas exposure during the war. The Veterans and Martyrs Affair Foundation (VMAF) database indicated that there were 196 patients with severe ophthalmologic complications due to chemical weapons exposure. Of these, those who gave consent (n = 147) entered into the study. Quality of life was measured using the 36-item Short Form Health Survey (SF-36) and scores were compared to those of the general public. In addition logistic regression analysis was performed to indicate variables that contribute to physical and mental health related quality of life. The mean age of the patients was 44.8 (SD = 8.7) ranging from 21 to 75 years. About one-third of the cases (n= 50) reported exposure to chemical weapons more than once. The mean exposure duration to sulfur mustard gas was 21.6 years (SD = 1.2). The lowest scores on the SF-36 subscales were found to be: the role physical and the general health. Quality of life in chemical warfare victims who had ophthalmologic problems was significantly lower than the general public (P chemical warfare victims with ophthalmologic complications suffer from poor health related quality of life. It seems that the need for provision of health and support for this population is urgent. In addition, further research is necessary to measure health related quality of life in victims with different types of disabilities in order to support and enhance quality of life among this population.

Revisiting the definition of the electronic chemical potential, chemical hardness, and softness at finite temperatures

Energy Technology Data Exchange (ETDEWEB)

Franco-Pérez, Marco, E-mail: qimfranco@hotmail.com, E-mail: jlgm@xanum.uam.mx [Departamento de Química, Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael Atlixco 186, México D. F. 09340 (Mexico); Department of Chemistry, McMaster University, Hamilton, Ontario L8S 4M1 (Canada); Gázquez, José L., E-mail: qimfranco@hotmail.com, E-mail: jlgm@xanum.uam.mx [Departamento de Química, Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael Atlixco 186, México D. F. 09340 (Mexico); Ayers, Paul W. [Department of Chemistry, McMaster University, Hamilton, Ontario L8S 4M1 (Canada); Vela, Alberto [Departamento de Química, Centro de Investigación y de Estudios Avanzados (Cinvestav), Av. Instituto Politécnico Nacional 2508, México D. F. 07360 (Mexico)

2015-10-21

We extend the definition of the electronic chemical potential (μ{sub e}) and chemical hardness (η{sub e}) to finite temperatures by considering a reactive chemical species as a true open system to the exchange of electrons, working exclusively within the framework of the grand canonical ensemble. As in the zero temperature derivation of these descriptors, the response of a chemical reagent to electron-transfer is determined by the response of the (average) electronic energy of the system, and not by intrinsic thermodynamic properties like the chemical potential of the electron-reservoir which is, in general, different from the electronic chemical potential, μ{sub e}. Although the dependence of the electronic energy on electron number qualitatively resembles the piecewise-continuous straight-line profile for low electronic temperatures (up to ca. 5000 K), the introduction of the temperature as a free variable smoothens this profile, so that derivatives (of all orders) of the average electronic energy with respect to the average electron number exist and can be evaluated analytically. Assuming a three-state ensemble, well-known results for the electronic chemical potential at negative (−I), positive (−A), and zero values of the fractional charge (−(I + A)/2) are recovered. Similarly, in the zero temperature limit, the chemical hardness is formally expressed as a Dirac delta function in the particle number and satisfies the well-known reciprocity relation with the global softness.

Incidence and characteristics of chemical burns.

Science.gov (United States)

Koh, Dong-Hee; Lee, Sang-Gil; Kim, Hwan-Cheol

2017-05-01

Chemical burns can lead to serious health outcomes. Previous studies about chemical burns have been performed based on burn center data so these studies have provided limited information about the incidence of chemical burns at the national level. The aim of this study was to evaluate the incidence and characteristics of chemical burns using nationwide databases. A cohort representing the Korean population, which was established using a national health insurance database, and a nationwide workers' compensation database were used to evaluate the incidence and characteristics of chemical burns. Characteristics of the affected body region, depth of burns, industry, task, and causative agents were analyzed from two databases. The incidence of chemical burns was calculated according to employment status. The most common regions involving chemical burns with hospital visits were the skin followed by the eyes. For skin lesions, the hands and wrists were the most commonly affected regions. Second degree burns were the most common in terms of depth of skin lesions. The hospital visit incidence was 1.96 per 10,000 person-year in the general population. The compensated chemical burns incidence was 0.17 per 10,000 person-year. Employees and the self-employed showed a significantly increased risk of chemical burns undergoing hospital visits compared to their dependents. Chemical burns on the skin and eyes are almost equally prevalent. The working environment was associated with increased risk of chemical burns. Our results may aid in estimating the size of the problem and prioritizing prevention of chemical burns. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

Chemical Disarmament: Current Problems in Implementing the Chemical Weapons Convention

Directory of Open Access Journals (Sweden)

Matoušek, J.

2006-03-01

Full Text Available The Chemical Weapons Convention (CWC is briefly characterised by stressing its main pillars, such as verified destruction ofCWstockpiles and destruction/conversion ofCWproduction facilities (CWPFs, verified non-production of CW by the chemical industries, assistance and protection, and international cooperation. The CWC´s leading principle in defining theCW(protecting it generally against scientific and technological development, i. e. so called General Purpose Criterion is thoroughly elucidated showing its relation to the CWC´s sophisticated verification system. Status of implementation (as of August 2005 shows main data obligatory declared by the States Parties (SP, among them 6 possessors of CW stockpiles (Russia, USA, India, South Korea, Albania and Libya. From the declared 71 373 agent-tons, 12 889 have been destroyed, from the declared 8 679 M items of munitions (containers, 2 420 have been destroyed, which means that the anticipated 10 years deadline for CW destruction (after entry into force – EIF will be not managed. For Russia and USA the allowed extension by another 5 years has been already agreed. From the 64 CWPFs (operational after 1946, declared by 12 SPs, 53 have been certified as destroyed/converted. The Organisation for the Prohibition of Chemical Weapons (OPCW is briefly presented and main results of the First Review Conference (2003 analysed on the base of the adopted principal documents. Future problems of implementing the CWC are connected in the first line with its universality, because among 16 non-SPs, several countries (located mainly in the Near East and on the Korean peninsula are presumed to be CW-possessors. Special emphasis is laid on both, threats and benefits of the scientific and technological development for current implementing the CWC as well as of its implementation in future after all CW stockpiles have been destroyed.

Using the Internet for Gerontology Education: Assessing and Improving Wikipedia

Science.gov (United States)

Infeld, Donna Lind; Adams, William C.

2013-01-01

Older adults, students, professionals, and the general public increasingly turn to the Internet and to Wikipedia for information. Wikipedia, the world's sixth most used website, is by far the most widely used open-source information site. Among its nearly four million English-language encyclopedia articles, how thorough is coverage of key…

Post-marketing surveillance of chemicals: organisations and databases : Workshop report

NARCIS (Netherlands)

Bouwmeester M; van Drongelen A; Graven C; Hernandez L; Herremans J; de Kaste D; Razenberg L; Vandebriel R; Piersma A; VTS; GZB

2018-01-01

The safety evaluation of chemicals is in general performed by the government, importer or manufacturer before marketing, and is based on (inter)national legislation. Less is known about the exact products in which chemicals are processed. Even though multiple institutions in the Netherlands are

Chemical Intolerance among Hairdressers in Denmark

DEFF Research Database (Denmark)

Tran, Marie Thi Dao; Elberling, Jesper; Skovbjerg, Sine

2013-01-01

To investigate the prevalence and the severity of fragrance-related symptoms among hairdressers in Denmark compared with the Danish general population. Further, to characterize former hairdressers who are severely chemically intolerant to fragranced products in relation to sex, age and health...

Chemical cosmology

CERN Document Server

Boeyens, Jan CA

2010-01-01

The composition of the most remote objects brought into view by the Hubble telescope can no longer be reconciled with the nucleogenesis of standard cosmology and the alternative explanation, in terms of the LAMBDA-Cold-Dark-Matter model, has no recognizable chemical basis. A more rational scheme, based on the chemistry and periodicity of atomic matter, opens up an exciting new interpretation of the cosmos in terms of projective geometry and general relativity. The response of atomic structure to environmental pressure predicts non-Doppler cosmical redshifts and equilibrium nucleogenesis by alp

Non-equilibrium Quasi-Chemical Nucleation Model

Science.gov (United States)

Gorbachev, Yuriy E.

2018-04-01

Quasi-chemical model, which is widely used for nucleation description, is revised on the basis of recent results in studying of non-equilibrium effects in reacting gas mixtures (Kolesnichenko and Gorbachev in Appl Math Model 34:3778-3790, 2010; Shock Waves 23:635-648, 2013; Shock Waves 27:333-374, 2017). Non-equilibrium effects in chemical reactions are caused by the chemical reactions themselves and therefore these contributions should be taken into account in the corresponding expressions for reaction rates. Corrections to quasi-equilibrium reaction rates are of two types: (a) spatially homogeneous (caused by physical-chemical processes) and (b) spatially inhomogeneous (caused by gas expansion/compression processes and proportional to the velocity divergency). Both of these processes play an important role during the nucleation and are included into the proposed model. The method developed for solving the generalized Boltzmann equation for chemically reactive gases is applied for solving the set of equations of the revised quasi-chemical model. It is shown that non-equilibrium processes lead to essential deviation of the quasi-stationary distribution and therefore the nucleation rate from its traditional form.

Biological Art of Producing Useful Chemicals

Indian Academy of Sciences (India)

Home; Journals; Resonance – Journal of Science Education; Volume 21; Issue 3. Metabolic Engineering: Biological Art of Producing Useful Chemicals. Ram Kulkarni. General Article Volume 21 Issue 3 March 2016 pp 233-237. Fulltext. Click here to view fulltext PDF. Permanent link:

Research in Chemical Kinetics, v.3

CERN Document Server

2012-01-01

This series of volumes aims to publish authoritative review articles on a wide range of exciting and contemporary topics in gas and condensed phase kinetics. Research in Chemical Kinetics complements the acclaimed series Comprehensive Chemical Kinetics, and is edited by the same team of professionals. The reviews contained in this volume are concise, topical accounts of specific research written by acknowledged experts. The authors summarize their latest work and place it in a general context. Particular strengths of the volume are the quality of the contributions and their top

Priority Environmental Chemical Contaminants in Meat

Science.gov (United States)

Brambilla, Gianfranco; Iamiceli, Annalaura; di Domenico, Alessandro

Generally, foods of animal origin play an important role in determining the exposure of human beings to contaminants of both biological and chemical origins (Ropkins & Beck, 2002; Lievaart et al., 2005). A potentially large number of chemicals could be considered, several of them deserving a particular attention due to their occurrence (contaminations levels and frequencies) and intake scenarios reflecting the differences existing in the economical, environmental, social and ecological contexts in which the “from-farm-to-fork” activities related to meat production are carried out (FAO - Food and Agriculture Organization, 2008).

Research in chemical kinetics, v.2

CERN Document Server

1994-01-01

This is the second volume in a new series, which aims to publish authoritative review articles on a wide range of exciting and contemporary topics in gas and condensed phase kinetics. Research in Chemical Kinetics complements the acclaimed series Comprehensive Chemical Kinetics, and is edited by the same team of professionals. The reviews contained in this volume are concise, topical accounts of specific research written by acknowledged experts. The authors summarize their latest work and place it in a general context. Particular strengths of the volume are the quality of the c

Elderly Adi Women of Arunachal Pradesh: "Living Encyclopedias" and Cultural Refugia in Biodiversity Conservation of the Eastern Himalaya, India

Science.gov (United States)

Singh, Ranjay K.; Rallen, Orik; Padung, Egul

2013-09-01

Elderly women of a particular socioecological system are considered to be "living encyclopedias" in biocultural knowledge systems. These women play a pivotal role in retaining and passing on biodiversity-related traditional knowledge to the next generations. Unfortunately the fast changing sociocultural values and the impact of modernity have rendered their knowledge somewhat less valuable and they are being treated as "cultural refugia." Our study on the importance of these women in the conservation of indigenous biodiversity was conducted in 14 randomly selected villages dominated by the Adi tribe of East Siang District, Arunachal Pradesh (northeast India). Data were collected from 531 women (381 elderly and 150 young to middle aged) during 2003-2008 using conventional social science methods and participatory rural appraisal. One innovative method, namely "recipe contest," was devised to mobilize Adi women of each village in order to energies them and explore their knowledge relating to traditional foods, ethnomedicines, and conservation of indigenous biodiversity. Results indicated that 55 plant species are being used by elderly Adi women in their food systems, while 34 plant species are integral parts of ethnomedicinal practices. These women identified different plant species found under multistory canopies of community forests. Elderly women were particularly skilled in preparing traditional foods including beverages and held significantly greater knowledge of indigenous plants than younger women. Lifelong experiences and cultural diversity were found to influence the significance of biodiversity use and conservation. The conservation of biodiversity occurs in three different habitats: jhum lands (shifting cultivation), Morang forest (community managed forests), and home gardens. The knowledge and practice of elderly women about habitats and multistory vegetations, regenerative techniques, selective harvesting, and cultivation practices contribute

Elderly Adi women of Arunachal Pradesh: "living encyclopedias" and cultural refugia in biodiversity conservation of the Eastern Himalaya, India.

Science.gov (United States)

Singh, Ranjay K; Rallen, Orik; Padung, Egul

2013-09-01

Elderly women of a particular socioecological system are considered to be "living encyclopedias" in biocultural knowledge systems. These women play a pivotal role in retaining and passing on biodiversity-related traditional knowledge to the next generations. Unfortunately the fast changing sociocultural values and the impact of modernity have rendered their knowledge somewhat less valuable and they are being treated as "cultural refugia." Our study on the importance of these women in the conservation of indigenous biodiversity was conducted in 14 randomly selected villages dominated by the Adi tribe of East Siang District, Arunachal Pradesh (northeast India). Data were collected from 531 women (381 elderly and 150 young to middle aged) during 2003-2008 using conventional social science methods and participatory rural appraisal. One innovative method, namely "recipe contest," was devised to mobilize Adi women of each village in order to energies them and explore their knowledge relating to traditional foods, ethnomedicines, and conservation of indigenous biodiversity. Results indicated that 55 plant species are being used by elderly Adi women in their food systems, while 34 plant species are integral parts of ethnomedicinal practices. These women identified different plant species found under multistory canopies of community forests. Elderly women were particularly skilled in preparing traditional foods including beverages and held significantly greater knowledge of indigenous plants than younger women. Lifelong experiences and cultural diversity were found to influence the significance of biodiversity use and conservation. The conservation of biodiversity occurs in three different habitats: jhum lands (shifting cultivation), Morang forest (community managed forests), and home gardens. The knowledge and practice of elderly women about habitats and multistory vegetations, regenerative techniques, selective harvesting, and cultivation practices contribute

Modeling release of chemicals from multilayer materials into food

Directory of Open Access Journals (Sweden)

Huang Xiu-Ling

2016-01-01

Full Text Available The migration of chemicals from materials into food is predictable by various mathematical models. In this article, a general mathematical model is developed to quantify the release of chemicals through multilayer packaging films based on Fick's diffusion. The model is solved numerically to elucidate the effects of different diffusivity values of different layers, distribution of chemical between two adjacent layers and between material and food, mass transfer at the interface of material and food on the migration process.

Chemical protection against ionizing radiation

International Nuclear Information System (INIS)

Livesey, J.C.; Reed, D.J.

1987-01-01

Over 40 years have passed since the research of the Manhattan Project suggested the possibility of chemical protection against ionizing radiation. During that time, much has been learned about the nature of radiation-induced injury and the factors governing the expression of that injury. Thousands of compounds have been tested for radioprotective efficacy, and numerous theories have been proposed to account for these actions. The literature on chemical radioprotection is large. In this article, the authors consider several of the mechanisms by which chemicals may protect against radiation injury. They have chosen to accent this view of radioprotector research as opposed to that research geared toward developing specific molecules as protective agents because they feel that such an approach is more beneficial in stimulating research of general applicability. This paper describes the matrix of biological factors upon which an exogenous radioprotector is superimposed, and examines evidence for and against various mechanisms by which these agents may protect biological systems against ionizing radiation. It concludes with a brief outlook for research in chemical radioprotection

Quality of life in chemical warfare survivors with ophthalmologic injuries: the first results form Iran Chemical Warfare Victims Health Assessment Study

Directory of Open Access Journals (Sweden)

Soroush Mohammad

2009-01-01

Full Text Available Abstract Background Iraq used chemical weapons extensively against the Iranians during the Iran-Iraq war (1980–1988. The aim of this study was to assess the health related quality of life (HRQOL in people who had ophthalmologic complications due to the sulfur mustard gas exposure during the war. Methods The Veterans and Martyrs Affair Foundation (VMAF database indicated that there were 196 patients with severe ophthalmologic complications due to chemical weapons exposure. Of these, those who gave consent (n = 147 entered into the study. Quality of life was measured using the 36-item Short Form Health Survey (SF-36 and scores were compared to those of the general public. In addition logistic regression analysis was performed to indicate variables that contribute to physical and mental health related quality of life. Results The mean age of the patients was 44.8 (SD = 8.7 ranging from 21 to 75 years. About one-third of the cases (n= 50 reported exposure to chemical weapons more than once. The mean exposure duration to sulfur mustard gas was 21.6 years (SD = 1.2. The lowest scores on the SF-36 subscales were found to be: the role physical and the general health. Quality of life in chemical warfare victims who had ophthalmologic problems was significantly lower than the general public (P Conclusion The study findings suggest that chemical warfare victims with ophthalmologic complications suffer from poor health related quality of life. It seems that the need for provision of health and support for this population is urgent. In addition, further research is necessary to measure health related quality of life in victims with different types of disabilities in order to support and enhance quality of life among this population.

Periodontal Emergencies in General Practice.

Science.gov (United States)

Wadia, Reena; Ide, Mark

2017-05-01

Diagnosing and managing periodontal emergencies is a common part of general dental practice. This article summarises the presentation, aetiology and management of the key periodontal emergencies, including gingival abscess, periodontal abscess, peri-coronitis/peri-coronal abscess, perio-endo lesion/ abscess, necrotising gingivitis and periodontitis, acute herpetic gingivostomatitis, acute physical/chemical/thermal injury and subgingival root fracture.

Commercial production of specialty chemicals and pharmaceuticals from biomass

Energy Technology Data Exchange (ETDEWEB)

McChesney, J.D. [Univ. of Mississippi, University, MS (United States)

1993-12-31

The chemical substances utilized in consumer products, and for pharmaceutical and agricultural uses are generally referred to as specialty chemicals. These may be flavor or fragrance substances, intermediates for synthesis of drugs or agrochemicals or the drugs or agrochemicals themselves, insecticides or insect pheromones or antifeedants, plant growth regulators, etc. These are in contrast to chemicals which are utilized in large quantities for fuels or preparation of plastics, lubricants, etc., which are usually referred to as industrial chemicals. The specific utilization of specialty chemicals is associated with a specific important physiochemical or biological property. They may possess unique properties as lubricants or waxes or have a very desirable biological activity such as a drug, agrochemical or perfume ingredient. These unique properties convey significant economic value to the specific specialty chemical. The economic commercial production of specialty chemicals commonly requires the isolation of a precursor or the specialty chemical itself from a natural source. The discovery, development and commercialization of specialty chemicals is presented and reviewed. The economic and sustainable production of specialty chemicals is discussed.

Donated chemical probes for open science.

Science.gov (United States)

Müller, Susanne; Ackloo, Suzanne; Arrowsmith, Cheryl H; Bauser, Marcus; Baryza, Jeremy L; Blagg, Julian; Böttcher, Jark; Bountra, Chas; Brown, Peter J; Bunnage, Mark E; Carter, Adrian J; Damerell, David; Dötsch, Volker; Drewry, David H; Edwards, Aled M; Edwards, James; Elkins, Jon M; Fischer, Christian; Frye, Stephen V; Gollner, Andreas; Grimshaw, Charles E; IJzerman, Adriaan; Hanke, Thomas; Hartung, Ingo V; Hitchcock, Steve; Howe, Trevor; Hughes, Terry V; Laufer, Stefan; Li, Volkhart Mj; Liras, Spiros; Marsden, Brian D; Matsui, Hisanori; Mathias, John; O'Hagan, Ronan C; Owen, Dafydd R; Pande, Vineet; Rauh, Daniel; Rosenberg, Saul H; Roth, Bryan L; Schneider, Natalie S; Scholten, Cora; Singh Saikatendu, Kumar; Simeonov, Anton; Takizawa, Masayuki; Tse, Chris; Thompson, Paul R; Treiber, Daniel K; Viana, Amélia Yi; Wells, Carrow I; Willson, Timothy M; Zuercher, William J; Knapp, Stefan; Mueller-Fahrnow, Anke

2018-04-20

Potent, selective and broadly characterized small molecule modulators of protein function (chemical probes) are powerful research reagents. The pharmaceutical industry has generated many high-quality chemical probes and several of these have been made available to academia. However, probe-associated data and control compounds, such as inactive structurally related molecules and their associated data, are generally not accessible. The lack of data and guidance makes it difficult for researchers to decide which chemical tools to choose. Several pharmaceutical companies (AbbVie, Bayer, Boehringer Ingelheim, Janssen, MSD, Pfizer, and Takeda) have therefore entered into a pre-competitive collaboration to make available a large number of innovative high-quality probes, including all probe-associated data, control compounds and recommendations on use (https://openscienceprobes.sgc-frankfurt.de">https://openscienceprobes.sgc-frankfurt.dehttps://openscienceprobes.sgc-frankfurt.de/">/). Here we describe the chemical tools and target-related knowledge that have been made available, and encourage others to join the project. © 2018, Müller et al.

Sensitivity of animals to chemical compounds links to metabolic rate.

NARCIS (Netherlands)

Baas, J.; Kooijman, S.A.L.M.

2015-01-01

Ecotoxicological studies have shown considerable variation in species sensitivity for chemical compounds, but general patterns in sensitivity are still not known. A better understanding of this sensitivity is important in the context of environmental risk assessment but also in a more general

TIS General Safety Group Annual Report 2000

CERN Document Server

Weingarten, W

2001-01-01

This report summarises the main activities of the General Safety (GS) Group of the Technical Inspection and Safety Division (TIS) during the year 2000, and the results obtained. The different topics in which the Group is active are covered: general safety inspections and ergonomy, electrical, chemistry and gas safety, chemical pollution containment and control, industrial hygiene, the safety of civil engineering works and outside contractors, fire prevention and the safety aspects of the LHC experiments.

Genetic susceptibility factors for multiple chemical sensitivity revisited

DEFF Research Database (Denmark)

Berg, Nikolaj Drimer; Rasmussen, Henrik Berg; Linneberg, Allan

2010-01-01

of this study was to investigate genetic susceptibility factors for MCS and self-reported chemical sensitivity in a population sample. Ninety six MCS patients and 1,207 controls from a general population divided into four severity groups of chemical sensitivity were genotyped for variants in the genes encoding......Multiple chemical sensitivity (MCS) is characterised by adverse effects due to exposure to low levels of chemical substances. Various genes, especially genes of importance to the metabolism of xenobiotic compounds, have been associated with MCS, but findings are inconsistent. The purpose...... significant (OR=1.2, p=0.28). Fast arylamine N-acetyltransferase 2 metaboliser status was associated with severity of chemical sensitivity only in the most severely affected group in the population sample (OR=3.1, p=0.04). The cholecystokinin 2 receptor allele with 21 CT repeats was associated with MCS when...

A New Topology of Solutions of Chemical Equations

International Nuclear Information System (INIS)

Risteski, Ice B.

2013-01-01

In this work is induced a new topology of solutions of chemical equations by virtue of point-set topology in an abstract stoichiometrical space. Subgenerators of this topology are the coefficients of chemical reaction. Complex chemical reactions, as those of direct reduction of hematite with a carbon, often exhibit distinct properties which can be interpreted as higher level mathematical structures. Here we used a mathematical model that exploits the stoichiometric structure, which can be seen as a topology too, to derive an algebraic picture of chemical equations. This abstract expression suggests exploring the chemical meaning of topological concept. Topological models at different levels of realism can be used to generate a large number of reaction modifications, with a particular aim to determine their general properties. The more abstract the theory is, the stronger the cognitive power is

Quasi-particles at finite chemical potential

International Nuclear Information System (INIS)

Gardim, F. G.; Steffens, F. M.

2010-01-01

We present in this work the thermodynamic consistent quasi-particle model at finite chemical potential, to describe the Quark Gluon Plasma composed of two light quarks and gluons. The quasi-particle general solution will be discussed, and comparison with perturbative QCD and lattice data will be shown.

Sustainable Chemical Processes and Products. New Design Methodology and Design Tools

NARCIS (Netherlands)

Korevaar, G.

2004-01-01

The current chemical industry is not sustainable, which leads to the fact that innovation of chemical processes and products is too often hazardous for society in general and the environment in particular. It really is a challenge to implement sustainability considerations in the design activities

How to Find Out in: Food Science.

Science.gov (United States)

Maine Univ., Orono. Raymond H. Fogler Library.

This library handbook is a guide for the student of food science. It lists some of the more useful materials and reference books basic to general research and gives their location in the Fogler Library at the University of Maine. Materials are listed in six categories: (1) dictionaries and encyclopedias, (2) U.S. and international documents, (3)…

availability analysis of chemicals for water treatment

African Journals Online (AJOL)

NIJOTECH

In most countries, chemicals are generally recognized as being vital in the production of potable water and will ... industries and water utility ventures are being started in Nigeria ... are being dumped into rivers thereby polluting them the more.

AI AND SAR APPROACHES FOR PREDICTING CHEMICAL CARCINOGENICITY: SURVEY AND STATUS REPORT

Science.gov (United States)

A wide variety of artificial intelligence (AI) and structure-activity relationship (SAR approaches have been applied to tackling the general problem of predicting rodent chemical carcinogenicity. Given the diversity of chemical structures and mechanisms relative to this endpoin...

Data Mining Approaches for Genomic Biomarker Development: Applications Using Drug Screening Data from the Cancer Genome Project and the Cancer Cell Line Encyclopedia.

Directory of Open Access Journals (Sweden)

David G Covell

Full Text Available Developing reliable biomarkers of tumor cell drug sensitivity and resistance can guide hypothesis-driven basic science research and influence pre-therapy clinical decisions. A popular strategy for developing biomarkers uses characterizations of human tumor samples against a range of cancer drug responses that correlate with genomic change; developed largely from the efforts of the Cancer Cell Line Encyclopedia (CCLE and Sanger Cancer Genome Project (CGP. The purpose of this study is to provide an independent analysis of this data that aims to vet existing and add novel perspectives to biomarker discoveries and applications. Existing and alternative data mining and statistical methods will be used to a evaluate drug responses of compounds with similar mechanism of action (MOA, b examine measures of gene expression (GE, copy number (CN and mutation status (MUT biomarkers, combined with gene set enrichment analysis (GSEA, for hypothesizing biological processes important for drug response, c conduct global comparisons of GE, CN and MUT as biomarkers across all drugs screened in the CGP dataset, and d assess the positive predictive power of CGP-derived GE biomarkers as predictors of drug response in CCLE tumor cells. The perspectives derived from individual and global examinations of GEs, MUTs and CNs confirm existing and reveal unique and shared roles for these biomarkers in tumor cell drug sensitivity and resistance. Applications of CGP-derived genomic biomarkers to predict the drug response of CCLE tumor cells finds a highly significant ROC, with a positive predictive power of 0.78. The results of this study expand the available data mining and analysis methods for genomic biomarker development and provide additional support for using biomarkers to guide hypothesis-driven basic science research and pre-therapy clinical decisions.

Noise-induced multistability in chemical systems: Discrete versus continuum modeling

Czech Academy of Sciences Publication Activity Database

Duncan, A.; Liao, S.; Vejchodský, Tomáš; Erban, R.; Grima, R.

2015-01-01

Roč. 91, č. 4 (2015), s. 042111 ISSN 1539-3755 EU Projects: European Commission(XE) 328008 - STOCHDETBIOMODEL Institutional support: RVO:67985840 Keywords : chemical master equation * chemical Fokker-Planck equation * multimodality Subject RIV: BA - General Mathematics Impact factor: 2.288, year: 2014 http://journals.aps.org/pre/abstract/10.1103/PhysRevE.91.042111

Chemical Education in India: Addressing Current Challenges and Optimizing Opportunities

Science.gov (United States)

Krishnan, Mangala Sunder; Brakaspathy, R.; Arunan, E.

2016-01-01

This article gives a brief introduction to the structure of higher education programs in chemical and general sciences in India. The lack of high-quality chemical education in India in the past is traced back to the economic and social developments of the past. Remedial measures undertaken recently to improve the overall quality of chemical…

Noise-induced multistability in chemical systems: Discrete versus continuum modeling

Czech Academy of Sciences Publication Activity Database

Duncan, A.; Liao, S.; Vejchodský, Tomáš; Erban, R.; Grima, R.

2015-01-01

Roč. 91, č. 4 (2015), s. 042111 ISSN 1539-3755 EU Projects: European Commission(XE) 328008 - STOCHDETBIOMODEL Institutional support: RVO:67985840 Keywords : chemical master equation * chemical Fokker-Planck equation * multimodality Subject RIV: BA - General Mathematics Impact factor: 2.288, year: 2014 http://journals. aps .org/pre/abstract/10.1103/PhysRevE.91.042111

Discussion on the Development of Green Chemistry and Chemical Engineering

Science.gov (United States)

Zhang, Yunshen

2017-11-01

Chemical industry plays a vital role in the development process of national economy. However, in view of the special nature of the chemical industry, a large number of poisonous and harmful substances pose a great threat to the ecological environment and human health in the entire process of raw material acquisition, production, transportation, product manufacturing, and the final practical application. Therefore, it is a general trend to promote the development of chemistry and chemical engineering towards a greener environment. This article will focus on some basic problems occurred in the development process of green chemistry and chemical engineering.

Chemical Remediation of Nickel(II) Waste: A Laboratory Experiment for General Chemistry Students

Science.gov (United States)

Corcoran, K. Blake; Rood, Brian E.; Trogden, Bridget G.

2011-01-01

This project involved developing a method to remediate large quantities of aqueous waste from a general chemistry laboratory experiment. Aqueous Ni(II) waste from a general chemistry laboratory experiment was converted into solid nickel hydroxide hydrate with a substantial decrease in waste volume. The remediation method was developed for a…

15 CFR 710.6 - Relationship between the Chemical Weapons Convention Regulations and the Export Administration...

Science.gov (United States)

2010-01-01

... INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS GENERAL INFORMATION AND OVERVIEW OF THE CHEMICAL WEAPONS CONVENTION REGULATIONS (CWCR) § 710.6 Relationship between the Chemical Weapons Convention Regulations and the Export Administration Regulations, the International...

CET89 - CHEMICAL EQUILIBRIUM WITH TRANSPORT PROPERTIES, 1989

Science.gov (United States)

Mcbride, B.

1994-01-01

Scientists and engineers need chemical equilibrium composition data to calculate the theoretical thermodynamic properties of a chemical system. This information is essential in the design and analysis of equipment such as compressors, turbines, nozzles, engines, shock tubes, heat exchangers, and chemical processing equipment. The substantial amount of numerical computation required to obtain equilibrium compositions and transport properties for complex chemical systems led scientists at NASA's Lewis Research Center to develop CET89, a program designed to calculate the thermodynamic and transport properties of these systems. CET89 is a general program which will calculate chemical equilibrium compositions and mixture properties for any chemical system with available thermodynamic data. Generally, mixtures may include condensed and gaseous products. CET89 performs the following operations: it 1) obtains chemical equilibrium compositions for assigned thermodynamic states, 2) calculates dilute-gas transport properties of complex chemical mixtures, 3) obtains Chapman-Jouguet detonation properties for gaseous species, 4) calculates incident and reflected shock properties in terms of assigned velocities, and 5) calculates theoretical rocket performance for both equilibrium and frozen compositions during expansion. The rocket performance function allows the option of assuming either a finite area or an infinite area combustor. CET89 accommodates problems involving up to 24 reactants, 20 elements, and 600 products (400 of which may be condensed). The program includes a library of thermodynamic and transport properties in the form of least squares coefficients for possible reaction products. It includes thermodynamic data for over 1300 gaseous and condensed species and transport data for 151 gases. The subroutines UTHERM and UTRAN convert thermodynamic and transport data to unformatted form for faster processing. The program conforms to the FORTRAN 77 standard, except for

Environmental issues and work: women with multiple chemical sensitivities.

Science.gov (United States)

Lipson, Juliene G; Doiron, Nathalie

2006-08-01

Multiple chemical sensitivities (MCS) is an acquired condition in which exposure to low levels of chemicals causes symptoms in multiple organ systems. Some 12%-16% of the U.S. population has some level of chemical sensitivity, 80% of whom are women. Attempts to reduce chemical exposures leads to enormous life difficulties at home, school, and workplace. We base our article on an ethnographic study of MCS in the United States and Canada. We describe here themes related to work issues in terms of a general trajectory of becoming sick from work exposures, coping with toxic physical environments and dealing with coworkers and, when unable to continue working, applying for workers' compensation, or disability status, or both.

The chemical industry - friend to the environment?

International Nuclear Information System (INIS)

1992-01-01

''The Chemical Industry - Friend to the Environment?'' was a symposium organised by the North East Region committee of the Industrial Division of the Royal Society of Chemistry. This volume contains typescripts from all the lectures given at the symposium. The general public appreciate the material comforts the Chemical Industry provides, for example textiles, ceramics, steel, speciality chemicals, drugs, prosthetics etc. However, for many their comfort is spoiled by the chemical poisoning of the environment through slag heaps, beaches and countryside littered with non-biodegradable unsightly plastic containers, poor air quality through NO x , CO 2 and chlorofluorocarbon emissions, and of course, nuclear waste. The occasional spillage of hazardous chemicals through road, rail and sea accidents do nothing to improve the Industry's image. The majority of these topics were discussed, though no one presumed to know how to remove the problems entirely but many suggestions were put forward as to how this might be achieved. Of the 13 papers presented three were specifically concerned with recycling of plastics, 9 with the environmental impacts of chemicals and one, which is indexed separately, was concerned with radioactive discharges into the environment from the Sellafield reprocessing plant. (Author)

students' chemical knowledge in photosynthesis and respiration

African Journals Online (AJOL)

IICBA01

For example, mere knowledge and recalling of the general equation of ... The choice of SS2 and US2 in the study was deliberate. SS2 students were ..... why did they not recall from their memories associated chemical processes? For all the ...

Why Leading Consumer Product Companies Develop Proactive Chemical Management Strategies

Science.gov (United States)

Scruggs, Caroline E.; Van Buren, Harry J.

2014-01-01

Scholars have studied the various pressures that companies face related to socially responsible behavior when stakeholders know the particular social issues under consideration. Many have examined social responsibility in the context of environmental responsibility and the general approaches companies take regarding environmental management. The issue of currently unregulated, but potentially hazardous, chemicals in consumer products is not well understood by the general public, but a number of proactive consumer product companies have voluntarily adopted strategies to minimize use of such chemicals. These companies are exceeding regulatory requirements by restricting from their products chemicals that could harm human or environmental health, despite the fact that these actions are costly. They do not usually advertise the details of their strategies to end consumers. This article uses interviews with senior environmental directors of 20 multinational consumer product companies to investigate why these companies engage in voluntary chemicals management. The authors conclude that the most significant reasons are to achieve a competitive advantage and stay ahead of regulations, manage relationships and maintain legitimacy with stakeholders, and put managerial values into practice. Many of the characteristics related to the case of chemicals management are extendable to other areas of stakeholder management in which risks to stakeholders are either unknown or poorly understood. PMID:27471326

Why Leading Consumer Product Companies Develop Proactive Chemical Management Strategies.

Science.gov (United States)

Scruggs, Caroline E; Van Buren, Harry J

2016-05-01

Scholars have studied the various pressures that companies face related to socially responsible behavior when stakeholders know the particular social issues under consideration. Many have examined social responsibility in the context of environmental responsibility and the general approaches companies take regarding environmental management. The issue of currently unregulated, but potentially hazardous, chemicals in consumer products is not well understood by the general public, but a number of proactive consumer product companies have voluntarily adopted strategies to minimize use of such chemicals. These companies are exceeding regulatory requirements by restricting from their products chemicals that could harm human or environmental health, despite the fact that these actions are costly. They do not usually advertise the details of their strategies to end consumers. This article uses interviews with senior environmental directors of 20 multinational consumer product companies to investigate why these companies engage in voluntary chemicals management. The authors conclude that the most significant reasons are to achieve a competitive advantage and stay ahead of regulations, manage relationships and maintain legitimacy with stakeholders, and put managerial values into practice. Many of the characteristics related to the case of chemicals management are extendable to other areas of stakeholder management in which risks to stakeholders are either unknown or poorly understood.

High-throughput screening of chemical effects on ...

Science.gov (United States)

Disruption of steroidogenesis by environmental chemicals can result in altered hormone levels causing adverse reproductive and developmental effects. A high-throughput assay using H295R human adrenocortical carcinoma cells was used to evaluate the effect of 2,060 chemical samples on steroidogenesis via HPLC-MS/MS quantification of 10 steroid hormones, including progestagens, glucocorticoids, androgens, and estrogens. The study employed a three stage screening strategy. The first stage established the maximum tolerated concentration (MTC; >70% viability) per sample. The second stage quantified changes in hormone levels at the MTC while the third stage performed concentration-response (CR) on a subset of samples. At all stages, cells were pre-stimulated with 10 µM forskolin for 48 h to induce steroidogenesis followed by chemical treatment for 48 h. Of the 2,060 chemical samples evaluated, 524 samples were selected for six-point CR screening, based in part on significantly altering at least 4 hormones at the MTC. CR screening identified 232 chemical samples with concentration-dependent effects on 17β-estradiol and/or testosterone, with 411 chemical samples showing an effect on at least one hormone across the steroidogenesis pathway. Clustering of the concentration-dependent chemical-mediated steroid hormone effects grouped chemical samples into five distinct profiles generally representing putative mechanisms of action, including CYP17A1 and HSD3B inhibition. A d

Chemical diversity in opisthobranch molluscs from scarcely investigated Indo-Pacific areas

Digital Repository Service at National Institute of Oceanography (India)

Wahidullah, S.; Guo, Y.-W.; Fakhr, I.M.I.; Mollo, E.

on Nudibranchs Nudibranchs are exclusively carnivorous with a broad range of alimentary habits. They appear to have the ability to sequester, accumulate and modify dietary metabolites as well as to synthesize defensive compounds de novo (Cimino and Ghiselin... of the chemical data reviewed in this chapter, taking into account alimentary habits and geographical chemical variations, suggests some interesting generalizations. 8.6.1 Nudibranchs The intra-specific geographic variations observed in the chemical...

Chemical decontamination of radioactive waste

International Nuclear Information System (INIS)

Mohamed, H.I.

2006-01-01

Radioactive wastes are generated in a number of different kinds of facilities and arise in a wide range of concentrations of radioactive materials and in a variety of physical and chemical forms. There is also a variety of alternatives for treatment and conditioning of the wastes prior disposal. The importance of treatment of radioactive waste for protection of human and environment has long been recognized and considerable experience has gained in this field. Generally, the methods used for treatment of radioactive wastes can be classified into three type's biological, physical and chemical treatment this physical treatment it gives good result than biological treatment. Chemical treatment is fewer hazards and gives good result compared with biological and physical treatments. Chemical treatment is fewer hazards and gives good result compared with biological and physical treatments. In chemical treatment there are different procedures, solvent extraction, ion exchange, electro dialysis but solvent extraction is best one because high purity can be optioned on the other hand the disadvantage that it is expensive. Beside the solvent extraction technique one can be used is ion exchange which gives reasonable result, but requires pretreatment that to avoid in closing of column by colloidal and large species. Electro dialysis technique gives quite result but less than solvent extraction and ion exchange technique the advantage is a cheep.(Author)

Evaluation of an Integrated Approach Involving Chemical and ...

African Journals Online (AJOL)

Chemical and bio-remediation measures for the detoxification of pollutants such as cyanide and heavy metals in mine tailings ... in treated effluent released into natural water bodies after bacterial degradation was generally within international ...

Accurate quantum chemical calculations

Science.gov (United States)

Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Taylor, Peter R.

1989-01-01

An important goal of quantum chemical calculations is to provide an understanding of chemical bonding and molecular electronic structure. A second goal, the prediction of energy differences to chemical accuracy, has been much harder to attain. First, the computational resources required to achieve such accuracy are very large, and second, it is not straightforward to demonstrate that an apparently accurate result, in terms of agreement with experiment, does not result from a cancellation of errors. Recent advances in electronic structure methodology, coupled with the power of vector supercomputers, have made it possible to solve a number of electronic structure problems exactly using the full configuration interaction (FCI) method within a subspace of the complete Hilbert space. These exact results can be used to benchmark approximate techniques that are applicable to a wider range of chemical and physical problems. The methodology of many-electron quantum chemistry is reviewed. Methods are considered in detail for performing FCI calculations. The application of FCI methods to several three-electron problems in molecular physics are discussed. A number of benchmark applications of FCI wave functions are described. Atomic basis sets and the development of improved methods for handling very large basis sets are discussed: these are then applied to a number of chemical and spectroscopic problems; to transition metals; and to problems involving potential energy surfaces. Although the experiences described give considerable grounds for optimism about the general ability to perform accurate calculations, there are several problems that have proved less tractable, at least with current computer resources, and these and possible solutions are discussed.

Entropy Generation in a Chemical Reaction

Science.gov (United States)

Miranda, E. N.

2010-01-01

Entropy generation in a chemical reaction is analysed without using the general formalism of non-equilibrium thermodynamics at a level adequate for advanced undergraduates. In a first approach to the problem, the phenomenological kinetic equation of an elementary first-order reaction is used to show that entropy production is always positive. A…

The PubChem chemical structure sketcher

Directory of Open Access Journals (Sweden)

Ihlenfeldt Wolf D

2009-12-01

Full Text Available Abstract PubChem is an important public, Web-based information source for chemical and bioactivity information. In order to provide convenient structure search methods on compounds stored in this database, one mandatory component is a Web-based drawing tool for interactive sketching of chemical query structures. Web-enabled chemical structure sketchers are not new, being in existence for years; however, solutions available rely on complex technology like Java applets or platform-dependent plug-ins. Due to general policy and support incident rate considerations, Java-based or platform-specific sketchers cannot be deployed as a part of public NCBI Web services. Our solution: a chemical structure sketching tool based exclusively on CGI server processing, client-side JavaScript functions, and image sequence streaming. The PubChem structure editor does not require the presence of any specific runtime support libraries or browser configurations on the client. It is completely platform-independent and verified to work on all major Web browsers, including older ones without support for Web2.0 JavaScript objects.

Equilibrium statistical mechanics

CERN Document Server

Mayer, J E

1968-01-01

The International Encyclopedia of Physical Chemistry and Chemical Physics, Volume 1: Equilibrium Statistical Mechanics covers the fundamental principles and the development of theoretical aspects of equilibrium statistical mechanics. Statistical mechanical is the study of the connection between the macroscopic behavior of bulk matter and the microscopic properties of its constituent atoms and molecules. This book contains eight chapters, and begins with a presentation of the master equation used for the calculation of the fundamental thermodynamic functions. The succeeding chapters highlight t

Consumer product chemical weight fractions from ingredient lists

Science.gov (United States)

Assessing human exposures to chemicals in consumer products requires composition information. However, comprehensive composition data for products in commerce are not generally available. Many consumer products have reported ingredient lists that are constructed using specific gu...

Journal of Chemical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Solvent effect in aqueous media was treated using the integral equation formalism of the ... Reaction rate constants in aqueous media were generally found to be larger than those in gas phase. ... Journal of Chemical Sciences | News.

On chemical potential

International Nuclear Information System (INIS)

Araki, H.

1981-01-01

In the framework of the C*-algebra formalism of quantum statistical mechanics, the concept of chemical potential or its vector generalization in the case of an arbitrary (not necessarily abelian) separable compact gauge group (of the first kind) is described as an algebraic label of equilibrium states at a given inverse temperature β. It is mathematically attained by extending a (clustering) KMS state of the gauge-invariant part of a C*-algebra F to a state of F and by examining the KMS property of the extension. (Auth.)

Computational thermal, chemical, fluid, and solid mechanics for geosystems management.

Energy Technology Data Exchange (ETDEWEB)

Davison, Scott; Alger, Nicholas; Turner, Daniel Zack; Subia, Samuel Ramirez; Carnes, Brian; Martinez, Mario J.; Notz, Patrick K.; Klise, Katherine A.; Stone, Charles Michael; Field, Richard V., Jr.; Newell, Pania; Jove-Colon, Carlos F.; Red-Horse, John Robert; Bishop, Joseph E.; Dewers, Thomas A.; Hopkins, Polly L.; Mesh, Mikhail; Bean, James E.; Moffat, Harry K.; Yoon, Hongkyu

2011-09-01

This document summarizes research performed under the SNL LDRD entitled - Computational Mechanics for Geosystems Management to Support the Energy and Natural Resources Mission. The main accomplishment was development of a foundational SNL capability for computational thermal, chemical, fluid, and solid mechanics analysis of geosystems. The code was developed within the SNL Sierra software system. This report summarizes the capabilities of the simulation code and the supporting research and development conducted under this LDRD. The main goal of this project was the development of a foundational capability for coupled thermal, hydrological, mechanical, chemical (THMC) simulation of heterogeneous geosystems utilizing massively parallel processing. To solve these complex issues, this project integrated research in numerical mathematics and algorithms for chemically reactive multiphase systems with computer science research in adaptive coupled solution control and framework architecture. This report summarizes and demonstrates the capabilities that were developed together with the supporting research underlying the models. Key accomplishments are: (1) General capability for modeling nonisothermal, multiphase, multicomponent flow in heterogeneous porous geologic materials; (2) General capability to model multiphase reactive transport of species in heterogeneous porous media; (3) Constitutive models for describing real, general geomaterials under multiphase conditions utilizing laboratory data; (4) General capability to couple nonisothermal reactive flow with geomechanics (THMC); (5) Phase behavior thermodynamics for the CO2-H2O-NaCl system. General implementation enables modeling of other fluid mixtures. Adaptive look-up tables enable thermodynamic capability to other simulators; (6) Capability for statistical modeling of heterogeneity in geologic materials; and (7) Simulator utilizes unstructured grids on parallel processing computers.

Understanding the Complexity of a Rising China

Science.gov (United States)

2016-05-26

tourism , shipping, and remittances from Hong Kong and other sources that resulted in overall current accounts surpluses of (US) $900 million and (US) $1.2... tourism and a surge in FDI. 95 Encyclopedia of the Nations, s.v. “China - Balance of Payments...Expenditures General Public Services Foreign Affairs National Defense Public Security Education Science and Technology Culture, Sport and Media Social Safety

Guest Editorial: The Professional Status of European Chemists and Chemical Engineers.

Science.gov (United States)

Salzer, Reiner; Taylor, Philip; Majcen, Nineta H; De Angelis, Francesco; Wilmet, Sophie; Varella, Evangelia; Kozaris, Ioannis

2015-07-06

Which country pays its chemists and chemical engineers the highest salaries? Where can I find a new job quickest? Which chemical sub-discipline offers most jobs? Reliable answers for these and other questions have been derived from the first European employment survey for chemists and chemical engineers, which was carried out in 2013. Here we publish the first general evaluation of the results of this survey. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Using the biological literature a practical guide

CERN Document Server

Schmidt, Diane

2014-01-01

IntroductionSearching the Biological LiteratureGeneral SourcesAssociationsBibliographiesClassification, Nomenclature, and SystematicsDictionaries and EncyclopediasDirectoriesField GuidesSeriesFull-Text SourcesGeneral WorksGuides for young ScientistsGuides to the LiteratureHandbooksHistoriesMathematics and StatisticsMethods and TechniquesTextbooks and TreatisesWriting GuidesPeriodicalsReviews of the LiteratureAbstracts and IndexesBiochemistry and BiophysicsMolecular and Cellular BiologyGenetics, Biotechnology, and Developmental BiologyMicrobiology and ImmunologyEcology, Evolution, and Animal BehaviorPlant BiologyAnatomy and PhysiologyEntomologyZoologyIndex.

Chemical durability of silicoborate glasses

International Nuclear Information System (INIS)

Nieto, M.I.; Rodriguez, M.A.; Rubio, J.; Fernandez, A.; Oteo, J.L.

1987-01-01

A general view of the durability in silicoborate glasses is presented with more emphasis on the etching factors (chemical composition, lattice structure, pH...) the techniques used for this study and the experimental results. Likewise, the research presently developed in this area at the Instituto de Ceramica y Vidrio, CSIC, is related to the applications. Future research in this field is also mentioned. (author) 15 figs

Non-allergic cutaneous reactions in airborne chemical sensitivity--a population based study

DEFF Research Database (Denmark)

Berg, Nikolaj Drimer; Linneberg, Allan; Thyssen, Jacob Pontoppidan

2011-01-01

the relationship between cutaneous reactions from patch testing and self-reported severity of chemical sensitivity to common airborne chemicals. A total of 3460 individuals participating in a general health examination, Health 2006, were patch tested with allergens from the European standard series and screened...... most severe groups of self-reported sensitivity to airborne chemicals. When adjusting for confounding, associations were weakened, and only non-allergic cutaneous reactions were significantly associated with individuals most severely affected by inhalation of airborne chemicals (odds ratio = 2.5, p = 0...

Chemical immobilisation of humic acid on silica

NARCIS (Netherlands)

Koopal, L.K.; Yang, Y.; Minnaard, A.J.; Theunissen, P.L.M.; Riemsdijk, W.H. van

1998-01-01

Immobilisation of purified Aldrich humic acid (PAHA) on aminopropyl silica and glutaraldehyde-activated aminopropyl silica has been investigated. In general the humic acid is bound to the solid by both physical and chemical bonds. The physically adsorbed HA can be released to a large extent at high

Chemical evolution of the galactic disk

International Nuclear Information System (INIS)

Wyse, R.F.G.; Gilmore, G.

1987-01-01

The distribution of enriched material in the stars and gas of their Galaxy contains information pertaining to the chemical evolution of the Milky Way from its formation epoch to the present day, and provides general constraints on theories of galaxy formation. The separate stellar components of the Galaxy cannot readily be understood if treated in isolation, but a reasonably self-consistent model for Galactic chemical evolution may be found if one considers together the chemical properties of the extreme spheroid, thick disk and thin disk populations of the Galaxy. The three major stellar components of the Galaxy are characterized by their distinct spatial distributions, metallicity structure, and kinematics, with the newly-identified thick disk being approximately three times more massive than the classical metal-poor, non-rotating extreme spheroid. Stellar evolution in the thick disk straightforwardly provides the desired pre-enrichment for resolution of the thin disk G dwarf problem

Semiconductor device-based sensors for gas, chemical, and biomedical applications

CERN Document Server

Ren, Fan

2011-01-01

Sales of U.S. chemical sensors represent the largest segment of the multi-billion-dollar global sensor market, which includes instruments for chemical detection in gases and liquids, biosensors, and medical sensors. Although silicon-based devices have dominated the field, they are limited by their general inability to operate in harsh environments faced with factors such as high temperature and pressure. Exploring how and why these instruments have become a major player, Semiconductor Device-Based Sensors for Gas, Chemical, and Biomedical Applications presents the latest research, including or

Encyclopedia of well logging

International Nuclear Information System (INIS)

Desbrandes, R.

1985-01-01

The 16 chapters of this book aim to provide students, trainees and engineers with a manual covering all well-logging measurements ranging from drilling to productions, from oil to minerals going by way of geothermal energy. Each chapter is a summary but a bibliography is given at the end of each chapter. Well-logging during drilling, wireline logging equipment and techniques, petroleum logging, data processing of borehole data, interpretation of well-logging, sampling tools, completion and production logging, logging in relief wells to kill off uncontrolled blowouts, techniques for high temperature geothermal energy, small-scale mining and hydrology, logging with oil-base mud and finally recommended logging programs are all topics covered. There is one chapter on nuclear well-logging which is indexed separately. (UK)

Electronic circuit encyclopedia 2

Energy Technology Data Exchange (ETDEWEB)

Park, Sun Ho

1992-10-15

This book is composed of 15 chapters, which are amplification of weak signal and measurement circuit audio control and power amplification circuit, data transmission and wireless system, forwarding and isolation, signal converting circuit, counter and comparator, discriminator circuit, oscillation circuit and synthesizer, digital and circuit on computer image processing circuit, sensor drive circuit temperature sensor circuit, magnetic control and application circuit, motor driver circuit, measuring instrument and check tool and power control and stability circuit.

Guarani Paraguayo [Encyclopedia entry

OpenAIRE

Drude, S.

2005-01-01

Guaraní , Paraguaisches Guaraní, Eigen-Bez. Avañe’ẽ, Sprache in Paraguay (über 3,5 Mio. Sprecher, 95 % der Bev.), NO-Argentinien (bis zu 1 Mio. Sprecher) und S-Brasilien. Das zu den Tupí-Guaraní-Sprachen zählende G. ist eine der größten → Indianersprachen S-Amerikas (nach Ketschua und vor Aimara) und die einzige, die überwiegend von Nicht-Indianern gebraucht wird. Seit den 1990-Jahren ist das G. in Paraguay als Nationalsprache anerkannt und wird auch in Schulen verwendet. Das G. wurde durch d...

Microsoft Encarta 99 Encyclopedia

African Journals Online (AJOL)

Finally, a future is envisioned in which the Internet will be the logical culmination of the ultimate potential of compu- ters as accessible, user-friendly reference .... The microstructure. In this article the central focus is on the ways in which Encarta 99 guides the user to the required information and not on the information itself.

Electronic circuit encyclopedia 2

International Nuclear Information System (INIS)

Park, Sun Ho

1992-10-01

This book is composed of 15 chapters, which are amplification of weak signal and measurement circuit audio control and power amplification circuit, data transmission and wireless system, forwarding and isolation, signal converting circuit, counter and comparator, discriminator circuit, oscillation circuit and synthesizer, digital and circuit on computer image processing circuit, sensor drive circuit temperature sensor circuit, magnetic control and application circuit, motor driver circuit, measuring instrument and check tool and power control and stability circuit.

Medical Encyclopedia: MedlinePlus

Science.gov (United States)

... Duplication for commercial use must be authorized in writing by ADAM Health Solutions. About MedlinePlus Site Map FAQs Customer Support Get email updates Subscribe to RSS Follow us Disclaimers Copyright ...

[Chemical weapons and chemical terrorism].

Science.gov (United States)

Nakamura, Katsumi

2005-10-01

Chemical Weapons are kind of Weapons of Mass Destruction (WMD). They were used large quantities in WWI. Historically, large quantities usage like WWI was not recorded, but small usage has appeared now and then. Chemical weapons are so called "Nuclear weapon for poor countrys" because it's very easy to produce/possession being possible. They are categorized (1) Nerve Agents, (2) Blister Agents, (3) Cyanide (blood) Agents, (4) Pulmonary Agents, (5) Incapacitating Agents (6) Tear Agents from the viewpoint of human body interaction. In 1997 the Chemical Weapons Convention has taken effect. It prohibits chemical weapons development/production, and Organization for the Prohibition of Chemical Weapons (OPCW) verification regime contributes to the chemical weapons disposal. But possibility of possession/use of weapons of mass destruction by terrorist group represented in one by Matsumoto and Tokyo Subway Sarin Attack, So new chemical terrorism countermeasures are necessary.

Second order elasticity at hypersonic frequencies of reactive polyurethanes as seen by generalized Cauchy relations

International Nuclear Information System (INIS)

Philipp, M; Vergnat, C; Mueller, U; Sanctuary, R; Baller, J; Krueger, J K; Possart, W; Alnot, P

2009-01-01

The non-equilibrium process of polymerization of reactive polymers can be accompanied by transition phenomena like gelation or the chemical glass transition. The sensitivity of the mechanical properties at hypersonic frequencies-including the generalized Cauchy relation-to these transition phenomena is studied for three different polyurethanes using Brillouin spectroscopy. As for epoxies, the generalized Cauchy relation surprisingly holds true for the non-equilibrium polymerization process and for the temperature dependence of polyurethanes. Neither the sol-gel transition nor the chemical and thermal glass transitions are visible in the representation of the generalized Cauchy relation. Taking into account the new results and combining them with general considerations about the elastic properties of the isotropic state, an improved physical foundation of the generalized Cauchy relation is proposed.

Second order elasticity at hypersonic frequencies of reactive polyurethanes as seen by generalized Cauchy relations

Energy Technology Data Exchange (ETDEWEB)

Philipp, M; Vergnat, C; Mueller, U; Sanctuary, R; Baller, J; Krueger, J K [Laboratoire de Physique des Materiaux, Universite du Luxembourg, 162A, avenue de la Faiencerie, L-1511 Luxembourg (Luxembourg); Possart, W [Fachbereich Werkstoffwissenschaften, Universitaet des Saarlandes, D-66123 Saarbruecken (Germany); Alnot, P [LPMI, Universite Nancy (France)], E-mail: martine.philipp@uni.lu

2009-01-21

The non-equilibrium process of polymerization of reactive polymers can be accompanied by transition phenomena like gelation or the chemical glass transition. The sensitivity of the mechanical properties at hypersonic frequencies-including the generalized Cauchy relation-to these transition phenomena is studied for three different polyurethanes using Brillouin spectroscopy. As for epoxies, the generalized Cauchy relation surprisingly holds true for the non-equilibrium polymerization process and for the temperature dependence of polyurethanes. Neither the sol-gel transition nor the chemical and thermal glass transitions are visible in the representation of the generalized Cauchy relation. Taking into account the new results and combining them with general considerations about the elastic properties of the isotropic state, an improved physical foundation of the generalized Cauchy relation is proposed.

Second order elasticity at hypersonic frequencies of reactive polyurethanes as seen by generalized Cauchy relations.

Science.gov (United States)

Philipp, M; Vergnat, C; Müller, U; Sanctuary, R; Baller, J; Possart, W; Alnot, P; Krüger, J K

2009-01-21

The non-equilibrium process of polymerization of reactive polymers can be accompanied by transition phenomena like gelation or the chemical glass transition. The sensitivity of the mechanical properties at hypersonic frequencies-including the generalized Cauchy relation-to these transition phenomena is studied for three different polyurethanes using Brillouin spectroscopy. As for epoxies, the generalized Cauchy relation surprisingly holds true for the non-equilibrium polymerization process and for the temperature dependence of polyurethanes. Neither the sol-gel transition nor the chemical and thermal glass transitions are visible in the representation of the generalized Cauchy relation. Taking into account the new results and combining them with general considerations about the elastic properties of the isotropic state, an improved physical foundation of the generalized Cauchy relation is proposed.

Non-allergic cutaneous reactions in airborne chemical sensitivity--a population based study

DEFF Research Database (Denmark)

Berg, Nikolaj Drimer; Linneberg, Allan; Thyssen, Jacob Pontoppidan

2011-01-01

the relationship between cutaneous reactions from patch testing and self-reported severity of chemical sensitivity to common airborne chemicals. A total of 3460 individuals participating in a general health examination, Health 2006, were patch tested with allergens from the European standard series and screened...... for chemical sensitivity with a standardised questionnaire dividing the participants into four severity groups of chemical sensitivity. Both allergic and non-allergic cutaneous reactions--defined as irritative, follicular, or doubtful allergic reactions--were analysed in relationship with severity of chemical...... most severe groups of self-reported sensitivity to airborne chemicals. When adjusting for confounding, associations were weakened, and only non-allergic cutaneous reactions were significantly associated with individuals most severely affected by inhalation of airborne chemicals (odds ratio = 2.5, p = 0...

Chemical Processing Department monthly report for February 1957

Energy Technology Data Exchange (ETDEWEB)

1957-03-21

This report from the Chemical Processing Department at HAPO, discusses the following: Production operation, purex operation, redox operation, finished products operation, power and general maintenance operation, financial operation, facilities engineering operation, research and engineering operation, and employee relations operation.

Instrumentation for chemical and radiochemical monitoring in nuclear power plants

International Nuclear Information System (INIS)

Nordmann, F.; Ballard, G.

2009-01-01

This article details the instrumentation implemented in French nuclear power plants for the monitoring of chemical and radiochemical effluents with the aim of limiting their environmental impact. It describes the controls performed with chemical automata for the search for drifts, anomalies or pollution in a given circuit. The operation principles of the different types of chemical automata are explained as well as the manual controls performed on samples manually collected. Content: 1 - general considerations; 2 - objectives of the chemical monitoring: usefulness of continuous monitoring with automata, transmission to control rooms and related actions, redundancy of automata; 3 - instrumentation and explanations for the main circuits: principle of chemical automata monitoring, instrumentation of the main primary circuit, instrumentation of the main secondary circuit, instrumentation of the tertiary circuit, preparation of water makeup (demineralized water), other loops, instrumentation for effluents and environment monitoring, measurement principles of chemical automata, control and maintenance of chemical automata; 4 - manual controls after sampling; 5 - radiochemical monitoring: automatized radiochemical measurements, manual radiochemical measurements; 6 - conclusion

Large Nc QCD at nonzero chemical potential

International Nuclear Information System (INIS)

Cohen, Thomas D.

2004-01-01

The general issue of large N c QCD at nonzero chemical potential is considered with a focus on understanding the difference between large N c QCD with an isospin chemical potential and large N c QCD with a baryon chemical potential. A simple diagrammatic analysis analogous to 't Hooft's analysis at μ=0 implies that the free energy with a given baryon chemical potential is equal to the free energy with an isospin chemical potential of the same value plus 1/N c corrections. Phenomenologically, these two systems behave quite differently. A scenario to explain this difference in light of the diagrammatic analysis is explored. This scenario is based on a phase transition associated with pion condensation when the isospin chemical potential exceeds m π /2; associated with this transition there is breakdown of the 1/N c expansion--in the pion condensed phase there is a distinct 1/N c expansion including a larger set of diagrams. While this scenario is natural, there are a number of theoretical issues which at least superficially challenge it. Most of these can be accommodated. However, the behavior of quenched QCD which raises a number of apparently analogous issues cannot be easily understood completely in terms of an analogous scenario. Thus, the overall issue remains open

Higher spin entanglement entropy at finite temperature with chemical potential

Energy Technology Data Exchange (ETDEWEB)

Chen, Bin [Department of Physics and State Key Laboratory of Nuclear Physics and Technology,Peking University,Beijing 100871 (China); Collaborative Innovation Center of Quantum Matter,5 Yiheyuan Rd, Beijing 100871 (China); Center for High Energy Physics, Peking University,5 Yiheyuan Rd, Beijing 100871 (China); Beijing Center for Mathematics and Information Interdisciplinary Sciences, Beijing 100048 (China); Wu, Jie-qiang [Department of Physics and State Key Laboratory of Nuclear Physics and Technology,Peking University,Beijing 100871 (China)

2016-07-11

It is generally believed that the semiclassical AdS{sub 3} higher spin gravity could be described by a two dimensional conformal field theory with W-algebra symmetry in the large central charge limit. In this paper, we study the single interval entanglement entropy on the torus in the CFT with a W{sub 3} deformation. More generally we develop the monodromy analysis to compute the two-point function of the light operators under a thermal density matrix with a W{sub 3} chemical potential to the leading order. Holographically we compute the probe action of the Wilson line in the background of the spin-3 black hole with a chemical potential. We find exact agreement.

The additivity of radionuclide and chemical risk estimates in performance evaluation of mixed-waste sites

International Nuclear Information System (INIS)

Till, J.E.; Meyer, K.R.

1990-01-01

Methods for assessing radioactive waste sites that contain chemical constituents are in the formative stages. In evaluating these sites, a key concern will be the hazard to personnel involved in cleanup work and to the general population. This paper focuses on what we have learned from pathway analysis and risk assessment about providing a combined estimate of risk from exposure to both chemicals and radionuclides. Quantitative radiation risk assessment involves a high degree of uncertainty. Chemical risk assessment generally does not provide quantitative results. Thus, it is not currently possible to develop a useful, quantitative combined risk assessment for mixed-waste sites

General constraints on the age and chemical evolution of the Galaxy

International Nuclear Information System (INIS)

Meyer, B.S.; Schramm, D.N.

1986-05-01

The formalism of Schramm and Wasserburg (1970) for determining the mean age of the elements is extended. Model-independent constraints (constraints that are independent of a specific form for the effective nucleosynthesis rate and Galactic chemical evolution over time) are derived on the first four terms in the expansion giving the mean age of the elements, and from these constraints limits are derived on the total duration of nucleosynthesis. These limits require only input of the Schramm-Wasserburg parameter Δ/sup max/ and of the ratio of the mean time for formation of the elements to the total duration of nucleosynthesis, t/sub nu//T. The former quantity is a function of nuclear input parameters. Limits on the latter are obtained from constraints on the relative rate of nucleosynthesis derived from the 232 Th/ 238 U, 235 U/ 238 U, and shorter-lived chronometric pairs. 65 refs

General crystal in prebiotic context

International Nuclear Information System (INIS)

Simon, I.

1993-09-01

General crystal is an extension of the crystal concept to any form of matter which exhibit neighbour structure determination. This extension makes many results of solid state physics applicable to heterogeneous matter. Among other it includes the description of phase transition from random to unique structure. The advantage of the general crystal approach is demonstrated on globular protein, on of the most important macromolecules of life, which are capable to adopt unique 3D structure spontaneously, regardless of the heterogeneous character of their chemical structure and conformation. It is suggested that the use of general crystal concept may help to find candidates among heterogeneous matters capable to spontaneous self-organization in the same way as crystallization results in unique structure of homogeneous matter, and to apply some of the results of solid state physics to describe the phase transition and other behaviour of this matter. (author). 10 refs

The Use of Chemical-Chemical Interaction and Chemical Structure to Identify New Candidate Chemicals Related to Lung Cancer.

Directory of Open Access Journals (Sweden)

Lei Chen

Full Text Available Lung cancer causes over one million deaths every year worldwide. However, prevention and treatment methods for this serious disease are limited. The identification of new chemicals related to lung cancer may aid in disease prevention and the design of more effective treatments. This study employed a weighted network, constructed using chemical-chemical interaction information, to identify new chemicals related to two types of lung cancer: non-small lung cancer and small-cell lung cancer. Then, a randomization test as well as chemical-chemical interaction and chemical structure information were utilized to make further selections. A final analysis of these new chemicals in the context of the current literature indicates that several chemicals are strongly linked to lung cancer.

The OSHA hazardous chemical occupational exposure standard for laboratories.

Science.gov (United States)

Armbruster, D A

1991-01-01

OSHA's chemical occupational exposure standard for laboratories is an outgrowth of the previously issued Hazard Communication Standard. The standard relieves laboratories from complying with general industry standards but does require compliance with specific laboratory guidelines. The heart of the standard is the creation of a Chemical Hygiene Plan (CHP). The CHP addresses major issues such as safety equipment and procedures, work practices, training, the designation of a chemical hygiene officer, and the provision of medical consultation and examination for affected employees. This new standard, in full effect as of January 31, 1991, presents yet another regulatory challenge to laboratory managers but also ensures a safer environment for laboratory workers.

Angioplasty: MedlinePlus Health Topic

Science.gov (United States)

... segment (Medical Encyclopedia) Also in Spanish Directional coronary atherectomy (DCA) (Medical Encyclopedia) Also in Spanish Percutaneous transluminal ... segment Coronary artery balloon angioplasty - slideshow Directional coronary atherectomy ... transluminal coronary angioplasty (PTCA) Stent Related ...

Summaries of FY 1989 research in the chemical sciences

International Nuclear Information System (INIS)

1989-08-01

These summaries provide the scientific and technical public, as well as the legislative and executive branches of the Government, information, either generally or in some depth, about the Chemical Sciences program. Areas of research supported are indicated in the section headings, the ''Selected Topics of General Interest'' list, and the summaries themselves. Energy technologies that may be advanced by use of the basic knowledge generated in this program are included in the ''Selected Topics of General Interest'' list and are often referenced in the summaries

Extension of a semi-implicit shock-capturing algorithm for 3-D fully coupled, chemically reacting flows in generalized coordinates

International Nuclear Information System (INIS)

Shinn, J.L.; Yee, H.C.; Uenishi, K.; NASA, Ames Research Center, Moffett Field, CA; Vigyan Research Associates, Inc., Hampton, VA)

1987-01-01

A semiimplicit high-resolution shock-capturing method for multidimensional systems of hyperbolic conservation laws with stiff source terms has been developed by Yee and Shinn (1987). The goal of this work is to extend this method to solve the three-dimensional fully coupled Navier-Stokes equations for a hypersonic chemically reacting flow in generalized coordinates. In this formulation, the global continuity equation was replaced by all the species continuity equations. The shock-capturing technique is a second-order-accurate, symmetric total-variation-diminishing method which accounts fully and directly for the coupling among the fluid and all the species. To verify the current approach, it was implemented into an existing computer code which contained the MacCormack method. Test results for a five-species reacting flow are shown to be oscillation-free around the shock, and the time spent per iteration only doubles when compared to the result using classical way of supplying numerical dissipation. The extra computation is more than justified by the elimination of spurious oscillation and nonlinear instability associated with the classical shock-capturing schemes in computing hypersonic reacting flows. 27 references

Chemometrics as a tool to analyse complex chemical mixtures

DEFF Research Database (Denmark)

Christensen, J. H.

Chemical characterisation of contaminant mixtures is important for environmental forensics and risk assessment. The great challenge in future research lies in develop- ing suitable, rapid, reliable and objective methods for analysis of the composition of complex chemical mixtures. This thesis...... describes the development of such methods for assessing the identity (chemical fingerprinting) and fate (e.g. biodegradation) of petroleum hydrocarbon mixtures. The methods comply with the general concept that suitable methods must be rapid and inexpensive, objective with limited human in- tervention...... and at the same time must consider a substantial fraction of compounds in the complex mixture. A combination of a) limited sample preparation, b) rapid chemical screening analysis, c) fast and semi-automatic pre-processing, d) compre- hensive multivariate statistical data analysis and e) objective data evaluation...

Laser-induced chemical vapor deposition reactions

International Nuclear Information System (INIS)

Teslenko, V.V.

1990-01-01

The results of investigation of chemical reactions of deposition of different substances from the gas phase when using the energy of pulse quasicontinuous and continuous radiation of lasers in the wave length interval from 0.193 to 10.6 μm are generalized. Main attetion is paid to deposition of inorganic substances including nonmetals (C, Si, Ge and others), metals (Cu, Au, Zn, Cd, Al, Cr, Mo, W, Ni) and some simple compounds. Experimental data on the effect of laser radiation parameters and reagent nature (hydrides, halogenides, carbonyls, alkyl organometallic compounds and others) on the deposition rate and deposit composition are described in detail. Specific features of laser-chemical reactions of deposition and prospects of their application are considered

Proposed minimum reporting standards for chemical analysis Chemical Analysis Working Group (CAWG) Metabolomics Standards Initiative (MSI)

Science.gov (United States)

Amberg, Alexander; Barrett, Dave; Beale, Michael H.; Beger, Richard; Daykin, Clare A.; Fan, Teresa W.-M.; Fiehn, Oliver; Goodacre, Royston; Griffin, Julian L.; Hankemeier, Thomas; Hardy, Nigel; Harnly, James; Higashi, Richard; Kopka, Joachim; Lane, Andrew N.; Lindon, John C.; Marriott, Philip; Nicholls, Andrew W.; Reily, Michael D.; Thaden, John J.; Viant, Mark R.

2013-01-01

There is a general consensus that supports the need for standardized reporting of metadata or information describing large-scale metabolomics and other functional genomics data sets. Reporting of standard metadata provides a biological and empirical context for the data, facilitates experimental replication, and enables the re-interrogation and comparison of data by others. Accordingly, the Metabolomics Standards Initiative is building a general consensus concerning the minimum reporting standards for metabolomics experiments of which the Chemical Analysis Working Group (CAWG) is a member of this community effort. This article proposes the minimum reporting standards related to the chemical analysis aspects of metabolomics experiments including: sample preparation, experimental analysis, quality control, metabolite identification, and data pre-processing. These minimum standards currently focus mostly upon mass spectrometry and nuclear magnetic resonance spectroscopy due to the popularity of these techniques in metabolomics. However, additional input concerning other techniques is welcomed and can be provided via the CAWG on-line discussion forum at http://msi-workgroups.sourceforge.net/ or http://Msi-workgroups-feedback@lists.sourceforge.net. Further, community input related to this document can also be provided via this electronic forum. PMID:24039616

A Decision Analytic Approach to Exposure-Based Chemical ...

Science.gov (United States)

The manufacture of novel synthetic chemicals has increased in volume and variety, but often the environmental and health risks are not fully understood in terms of toxicity and, in particular, exposure. While efforts to assess risks have generally been effective when sufficient data are available, the hazard and exposure data necessary to assess risks adequately are unavailable for the vast majority of chemicals in commerce. The US Environmental Protection Agency has initiated the ExpoCast Program to develop tools for rapid chemical evaluation based on potential for exposure. In this context, a model is presented in which chemicals are evaluated based on inherent chemical properties and behaviorally-based usage characteristics over the chemical’s life cycle. These criteria are assessed and integrated within a decision analytic framework, facilitating rapid assessment and prioritization for future targeted testing and systems modeling. A case study outlines the prioritization process using 51 chemicals. The results show a preliminary relative ranking of chemicals based on exposure potential. The strength of this approach is the ability to integrate relevant statistical and mechanistic data with expert judgment, allowing for an initial tier assessment that can further inform targeted testing and risk management strategies. The National Exposure Research Laboratory′s (NERL′s) Human Exposure and Atmospheric Sciences Division (HEASD) conducts research in suppor

Short Communication: Studies of antimicrobial activity and chemical ...

African Journals Online (AJOL)

Chemical constituents of the extract were also determined. The extract of was active against the test organisms including Escherischia coli, Pseudomonas aeruginosa and Candida albicans. Tannins, flavonoids, alkaloids, saponins, anthrax-quinones, starch, general glycosides and bitter principles were found to be present ...

CHMTRNS, Non-Equilibrium Chemical Transport Code

International Nuclear Information System (INIS)

Noorishad, J.; Carnahan, C.L.; Benson, L.V.

1998-01-01

1 - Description of program or function: CHMTRNS simulates solute transport for steady one-dimensional fluid flow by convection and diffusion or dispersion in a saturated porous medium based on the assumption of local chemical equilibrium. The chemical interactions included in the model are aqueous-phase complexation, solid-phase ion exchange of bare ions and complexes using the surface complexation model, and precipitation or dissolution of solids. The program can simulate the kinetic dissolution or precipitation for calcite and silica as well as irreversible dissolution of glass. Thermodynamic parameters are temperature dependent and are coupled to a companion heat transport simulator; thus, the effects of transient temperature conditions can be considered. Options for oxidation-reduction (redox) and C-13 fractionation as well as non-isothermal conditions are included. 2 - Method of solution: The governing equations for both reactive chemical and heat transport are discretized in time and space. For heat transport, the Crank-Nicolson approximation is used in conjunction with a LU decomposition and backward substitution solution procedure. To deal with the strong nonlinearity of the chemical transport equations, a generalized Newton-Raphson method is used

Neutral theory of chemical reaction networks

International Nuclear Information System (INIS)

Lee, Sang Hoon; Holme, Petter; Minnhagen, Petter; Bernhardsson, Sebastian; Kim, Beom Jun

2012-01-01

To what extent do the characteristic features of a chemical reaction network reflect its purpose and function? In general, one argues that correlations between specific features and specific functions are key to understanding a complex structure. However, specific features may sometimes be neutral and uncorrelated with any system-specific purpose, function or causal chain. Such neutral features are caused by chance and randomness. Here we compare two classes of chemical networks: one that has been subjected to biological evolution (the chemical reaction network of metabolism in living cells) and one that has not (the atmospheric planetary chemical reaction networks). Their degree distributions are shown to share the very same neutral system-independent features. The shape of the broad distributions is to a large extent controlled by a single parameter, the network size. From this perspective, there is little difference between atmospheric and metabolic networks; they are just different sizes of the same random assembling network. In other words, the shape of the degree distribution is a neutral characteristic feature and has no functional or evolutionary implications in itself; it is not a matter of life and death. (paper)

Application of Electro Chemical Machining for materials used in extreme conditions

Science.gov (United States)

Pandilov, Z.

2018-03-01

Electro-Chemical Machining (ECM) is the generic term for a variety of electrochemical processes. ECM is used to machine work pieces from metal and metal alloys irrespective of their hardness, strength or thermal properties, through the anodic dissolution, in aerospace, automotive, construction, medical equipment, micro-systems and power supply industries. The Electro Chemical Machining is extremely suitable for machining of materials used in extreme conditions. General overview of the Electro-Chemical Machining and its application for different materials used in extreme conditions is presented.

Genetics Home Reference: neutral lipid storage disease with myopathy

Science.gov (United States)

... named? Additional Information & Resources MedlinePlus (6 links) Encyclopedia: Hypothyroidism Encyclopedia: Type 2 Diabetes Health Topic: Cardiomyopathy Health Topic: Lipid Metabolism Disorders Health Topic: Muscle Disorders Health Topic: Pancreatitis Genetic and Rare Diseases ...

Kinetics of chemical reactions initiated by hot atoms

International Nuclear Information System (INIS)

Firsova, L.P.

1977-01-01

Modern ideas about kinetics of chemical reactions of hot atoms are generalized. The main points of the phenomenological theories (''kinetic theory'' of Wolfgang-Estrup hot reactions and the theory of ''reactions integral probability'' of Porter) are given. Physico-chemical models of elastic and non-elastic collisions are considered which are used in solving Boltzmann integro-differential equations and stochastic equations in the Porter theory. The principal formulas are given describing probabilities or yields of chemical reactions, initiated with hot atoms, depending on the distribution functions of hot particles with respect to energy. Briefly described are the techniques and the results of applying the phenomenological theories for interpretation of the experimental data obtained during nuclear reactions with hot atoms, photochemical investigations, etc. 96 references are given

Laser studies of chemical reaction and collision processes

Energy Technology Data Exchange (ETDEWEB)

Flynn, G. [Columbia Univ., New York, NY (United States)

1993-12-01

This work has concentrated on several interrelated projects in the area of laser photochemistry and photophysics which impinge on a variety of questions in combustion chemistry and general chemical kinetics. Infrared diode laser probes of the quenching of molecules with {open_quotes}chemically significant{close_quotes} amounts of energy in which the energy transferred to the quencher has, for the first time, been separated into its vibrational, rotational, and translational components. Probes of quantum state distributions and velocity profiles for atomic fragments produced in photodissociation reactions have been explored for iodine chloride.

Wet chemical synthesis of soluble gold nanogaps

DEFF Research Database (Denmark)

Jain, Titoo; Tang, Qingxin; Bjørnholm, Thomas

2014-01-01

NRs) in aqueous solution. Through controlled end-to-end assembly of the AuNRs into dimers or chains, facilitated via target molecules, they can be used as electrical contacts. In this way, the preparation of AuNR-molecule-AuNR junctions by wet chemical methods may afford a large number of identical devices...... with little variation in the interface between molecule and electrode (AuNR). In this Account, we highlight recent progress in using chemically synthesized AuNRs as building blocks for molecular electronic applications. We outline the general synthesis and properties of AuNRs and describe the aqueous growth...... in the nanogaps lets us spectroscopically characterize the molecules via surface-enhanced Raman scattering. We discuss the incorporation of oligopeptides functionalized with acetylene units having uniquely identifiable vibrational modes. This acetylene moiety allows chemical reactions to be performed in the gaps...

Education-industry partnership: the chemical industry experience

International Nuclear Information System (INIS)

Bricknell, D.J.

1994-01-01

The European Chemical Industry and the Nuclear Power Industry share similar problems and hopefully can share similar solutions to them. A recent survey of public opinion conducted on behalf of the chemical industry has shown that the general public knows little about the industry and does not trust it to behave responsibly. The industry is responding in two ways: firstly to demonstrate that it is a responsible member of the community by operating to the highest safety and environmental standards and by being open in its dealings with the public on such matters. Secondly the industry is working with the education system to ensure that the public has the opportunity to gain a good education in science, is able to make rational judgments about risks and benefits and is better able to understand and accept the role of the chemical industry in society

Rapid computation of chemical equilibrium composition - An application to hydrocarbon combustion

Science.gov (United States)

Erickson, W. D.; Prabhu, R. K.

1986-01-01

A scheme for rapidly computing the chemical equilibrium composition of hydrocarbon combustion products is derived. A set of ten governing equations is reduced to a single equation that is solved by the Newton iteration method. Computation speeds are approximately 80 times faster than the often used free-energy minimization method. The general approach also has application to many other chemical systems.

pyJac: Analytical Jacobian generator for chemical kinetics

Science.gov (United States)

Niemeyer, Kyle E.; Curtis, Nicholas J.; Sung, Chih-Jen

2017-06-01

Accurate simulations of combustion phenomena require the use of detailed chemical kinetics in order to capture limit phenomena such as ignition and extinction as well as predict pollutant formation. However, the chemical kinetic models for hydrocarbon fuels of practical interest typically have large numbers of species and reactions and exhibit high levels of mathematical stiffness in the governing differential equations, particularly for larger fuel molecules. In order to integrate the stiff equations governing chemical kinetics, generally reactive-flow simulations rely on implicit algorithms that require frequent Jacobian matrix evaluations. Some in situ and a posteriori computational diagnostics methods also require accurate Jacobian matrices, including computational singular perturbation and chemical explosive mode analysis. Typically, finite differences numerically approximate these, but for larger chemical kinetic models this poses significant computational demands since the number of chemical source term evaluations scales with the square of species count. Furthermore, existing analytical Jacobian tools do not optimize evaluations or support emerging SIMD processors such as GPUs. Here we introduce pyJac, a Python-based open-source program that generates analytical Jacobian matrices for use in chemical kinetics modeling and analysis. In addition to producing the necessary customized source code for evaluating reaction rates (including all modern reaction rate formulations), the chemical source terms, and the Jacobian matrix, pyJac uses an optimized evaluation order to minimize computational and memory operations. As a demonstration, we first establish the correctness of the Jacobian matrices for kinetic models of hydrogen, methane, ethylene, and isopentanol oxidation (number of species ranging 13-360) by showing agreement within 0.001% of matrices obtained via automatic differentiation. We then demonstrate the performance achievable on CPUs and GPUs using py

Coupling between solute transport and chemical reactions models

International Nuclear Information System (INIS)

Samper, J.; Ajora, C.

1993-01-01

During subsurface transport, reactive solutes are subject to a variety of hydrodynamic and chemical processes. The major hydrodynamic processes include advection and convection, dispersion and diffusion. The key chemical processes are complexation including hydrolysis and acid-base reactions, dissolution-precipitation, reduction-oxidation, adsorption and ion exchange. The combined effects of all these processes on solute transport must satisfy the principle of conservation of mass. The statement of conservation of mass for N mobile species leads to N partial differential equations. Traditional solute transport models often incorporate the effects of hydrodynamic processes rigorously but oversimplify chemical interactions among aqueous species. Sophisticated chemical equilibrium models, on the other hand, incorporate a variety of chemical processes but generally assume no-flow systems. In the past decade, coupled models accounting for complex hydrological and chemical processes, with varying degrees of sophistication, have been developed. The existing models of reactive transport employ two basic sets of equations. The transport of solutes is described by a set of partial differential equations, and the chemical processes, under the assumption of equilibrium, are described by a set of nonlinear algebraic equations. An important consideration in any approach is the choice of primary dependent variables. Most existing models cannot account for the complete set of chemical processes, cannot be easily extended to include mixed chemical equilibria and kinetics, and cannot handle practical two and three dimensional problems. The difficulties arise mainly from improper selection of the primary variables in the transport equations. (Author) 38 refs

LCA of Chemicals and Chemical Products

DEFF Research Database (Denmark)

Fantke, Peter; Ernstoff, Alexi

2018-01-01

This chapter focuses on the application of Life Cycle Assessment (LCA) to evaluate the environmental performance of chemicals as well as of products and processes where chemicals play a key role. The life cycle stages of chemical products, such as pharmaceuticals drugs or plant protection products......, are discussed and differentiated into extraction of abiotic and biotic raw materials, chemical synthesis and processing, material processing, product manufacturing, professional or consumer product use, and finally end-of-life . LCA is discussed in relation to other chemicals management frameworks and concepts...... including risk assessment , green and sustainable chemistry , and chemical alternatives assessment. A large number of LCA studies focus on contrasting different feedstocks or chemical synthesis processes, thereby often conducting a cradle to (factory) gate assessment. While typically a large share...

The effect of storage on Physical, Chemical and Bacteriological ...

African Journals Online (AJOL)

ADOWIE PERE

Ten (10) different companies' water samples each of bottled water (B) and ... after storage as with other chemical element except that lead showed ... Although it is true that soil generally ... organic pollutants, heavy metals and radioactive.

Encyclopedia of two-phase heat transfer and flow I fundamentals and methods

CERN Document Server

2015-01-01

The aim of the two–set series is to present a very detailed and up–to–date reference for researchers and practicing engineers in the fields of mechanical, refrigeration, chemical, nuclear and electronics engineering on the important topic of two-phase heat transfer and two-phase flow. The scope of the first set of 4 volumes presents the fundamentals of the two-phase flows and heat transfer mechanisms, and describes in detail the most important prediction methods, while the scope of the second set of 4 volumes presents numerous special topics and numerous applications, also including numerical simulation methods. Practicing engineers will find extensive coverage to applications involving: multi-microchannel evaporator cold plates for electronics cooling, boiling on enhanced tubes and tube bundles, flow pattern based methods for predicting boiling and condensation inside horizontal tubes, pressure drop methods for singularies (U-bends and contractions), boiling in multiport tubes, and boiling and condens...

Bride

DEFF Research Database (Denmark)

Pedersen, Else Marie Wiberg

2010-01-01

Encyclopedia article on the biblical metaphor "bride" and its use in medieval times and the Reformation Era......Encyclopedia article on the biblical metaphor "bride" and its use in medieval times and the Reformation Era...

Teaching Chemical Equilibrium with the Jigsaw Technique

Science.gov (United States)

Doymus, Kemal

2008-01-01

This study investigates the effect of cooperative learning (jigsaw) versus individual learning methods on students' understanding of chemical equilibrium in a first-year general chemistry course. This study was carried out in two different classes in the department of primary science education during the 2005-2006 academic year. One of the classes…

Chemical Detection Architecture for a Subway System [video

OpenAIRE

Ignacio, Joselito; Center for Homeland Defense and Security Naval Postgraduate School

2014-01-01

This proposed system process aims to improve subway safety through better enabling the rapid detection and response to a chemical release in a subway system. The process is designed to be location-independent and generalized to most subway systems despite each system's unique characteristics.

Computer-Aided Multiscale Modelling for Chemical Process Engineering

DEFF Research Database (Denmark)

Morales Rodriguez, Ricardo; Gani, Rafiqul

2007-01-01

Chemical processes are generally modeled through monoscale approaches, which, while not adequate, satisfy a useful role in product-process design. In this case, use of a multi-dimensional and multi-scale model-based approach has importance in product-process development. A computer-aided framework...

Generalized Stefan-Boltzmann Law

Science.gov (United States)

Montambaux, Gilles

2018-03-01

We reconsider the thermodynamic derivation by L. Boltzmann of the Stefan law and we generalize it for various different physical systems whose chemical potential vanishes. Being only based on classical arguments, therefore independent of the quantum statistics, this derivation applies as well to the saturated Bose gas in various geometries as to "compensated" Fermi gas near a neutrality point, such as a gas of Weyl Fermions. It unifies in the same framework the thermodynamics of many different bosonic or fermionic non-interacting gases which were until now described in completely different contexts.

Genetics Home Reference: REN-related kidney disease

Science.gov (United States)

... 2 Related Information How are genetic conditions and genes named? Additional Information & Resources MedlinePlus (5 links) Encyclopedia: Hyperkalemia Encyclopedia: Renin Health Topic: Anemia Health Topic: Gout Health Topic: Kidney Diseases Additional NIH Resources (2 ...

Chiropractic: MedlinePlus Health Topic

Science.gov (United States)

... for back pain (Medical Encyclopedia) Also in Spanish Topic Image MedlinePlus Email Updates Get Chiropractic updates by ... ENCYCLOPEDIA Chiropractic care for back pain Related Health Topics Back Pain Complementary and Integrative Medicine National Institutes ...

Wilms' Tumor: MedlinePlus Health Topic

Science.gov (United States)

... Spanish Wilms tumor (Medical Encyclopedia) Also in Spanish Topic Image MedlinePlus Email Updates Get Wilms Tumor updates ... ENCYCLOPEDIA After chemotherapy - discharge Wilms tumor Related Health Topics Kidney Cancer National Institutes of Health The primary ...

Pneumocystis Infections: MedlinePlus Health Topic

Science.gov (United States)

... Pneumocystis jiroveci pneumonia (Medical Encyclopedia) Also in Spanish Topic Image MedlinePlus Email Updates Get Pneumocystis Infections updates ... GO MEDICAL ENCYCLOPEDIA Pneumocystis jiroveci pneumonia Related Health Topics HIV/AIDS HIV/AIDS and Infections Pneumonia National ...

Psoriatic Arthritis: MedlinePlus Health Topic

Science.gov (United States)

... Handouts Psoriatic arthritis (Medical Encyclopedia) Also in Spanish Topic Image MedlinePlus Email Updates Get Psoriatic Arthritis updates ... this? GO MEDICAL ENCYCLOPEDIA Psoriatic arthritis Related Health Topics Arthritis Psoriasis National Institutes of Health The primary ...

Cardiac Arrest: MedlinePlus Health Topic

Science.gov (United States)

... Handouts Cardiac arrest (Medical Encyclopedia) Also in Spanish Topic Image MedlinePlus Email Updates Get Cardiac Arrest updates ... this? GO MEDICAL ENCYCLOPEDIA Cardiac arrest Related Health Topics Arrhythmia CPR Pacemakers and Implantable Defibrillators National Institutes ...

Kawasaki Disease: MedlinePlus Health Topic

Science.gov (United States)

... Spanish Kawasaki disease (Medical Encyclopedia) Also in Spanish Topic Image MedlinePlus Email Updates Get Kawasaki Disease updates ... GO MEDICAL ENCYCLOPEDIA Electrocardiogram Kawasaki disease Related Health Topics Vasculitis National Institutes of Health The primary NIH ...

Hearing Aids: MedlinePlus Health Topic

Science.gov (United States)

... for hearing loss (Medical Encyclopedia) Also in Spanish Topic Image MedlinePlus Email Updates Get Hearing Aids updates ... MEDICAL ENCYCLOPEDIA Devices for hearing loss Related Health Topics Cochlear Implants Hearing Disorders and Deafness National Institutes ...

Pulmonary Rehabilitation: MedlinePlus Health Topic

Science.gov (United States)

... Handouts Postural drainage (Medical Encyclopedia) Also in Spanish Topic Image MedlinePlus Email Updates Get Pulmonary Rehabilitation updates ... this? GO MEDICAL ENCYCLOPEDIA Postural drainage Related Health Topics Lung Diseases National Institutes of Health The primary ...

Empirical Force Fields for Mechanistic Studies of Chemical Reactions in Proteins.

Science.gov (United States)

Das, A K; Meuwly, M

2016-01-01

Following chemical reactions in atomistic detail is one of the most challenging aspects of current computational approaches to chemistry. In this chapter the application of adiabatic reactive MD (ARMD) and its multistate version (MS-ARMD) are discussed. Both methods allow to study bond-breaking and bond-forming processes in chemical and biological processes. Particular emphasis is put on practical aspects for applying the methods to investigate the dynamics of chemical reactions. The chapter closes with an outlook of possible generalizations of the methods discussed. © 2016 Elsevier Inc. All rights reserved.

Survey on methodologies in the risk assessment of chemical exposures in emergency response situations in Europe

DEFF Research Database (Denmark)

Heinälä, Milla; Gundert-Remy, Ursula; Wood, Maureen Heraty

2013-01-01

A scientifically sound assessment of the risk to human health resulting from acute chemical releases is the cornerstone for chemical incident prevention, preparedness and response. Although the general methodology to identify acute toxicity of chemicals has not substantially changed in the last....../corrosive chemicals will remain serious risks also in future the development of plausible scenarios for potential emerging risks is also needed. This includes risks from new mixtures and chemicals (e.g. nanoparticles)....

Physico-chemical properties of manufactured nanomaterials - Characterisation and relevant methods. An outlook based on the OECD Testing Programme.

NARCIS (Netherlands)

Rasmussen, Kirsten; Rauscher, Hubert; Mech, Agnieszka; Riego Sintes, Juan; Gilliland, Douglas; González, Mar; Kearns, Peter; Moss, Kenneth; Visser, Maaike; Groenewold, Monique; Bleeker, Eric A J

Identifying and characterising nanomaterials require additional information on physico-chemical properties and test methods, compared to chemicals in general. Furthermore, regulatory decisions for chemicals are usually based upon certain toxicological properties, and these effects may not be

Pregnant Employee Protection Program in a Large Chemical Company.

Science.gov (United States)

Frey, Gunild; Schuster, Michael; Oberlinner, Christoph; Queier-Wahrendorf, Annette; Lang, Stefan; Yong, Mei

2015-09-01

To assess whether a structured employee protection program for pregnant workers at a chemical company has an impact on pregnancy outcomes. Reported pregnancies (n = 1402) between 2003 and 2010 and their outcomes were documented using questionnaires at the time of pregnancy report, end of pregnancy, and 1 year later. Potential maternal exposures were assessed using job histories, workplace inspections, and questionnaires. Participation was 86% overall and was consistently high across subgroups.Pregnancy losses (10.9%), pregnancy complications, and preterm births (8.1%) were in agreement with rates in the general population and were independent of type of work and maternal exposure category. Pregnancy complication rates in this chemical company are not statistically elevated than that in the general population, as suggested in a previous study. The protection program may play a role in preventing complications that may have occurred.

Chemical Processing Department monthly report, May 1957

Energy Technology Data Exchange (ETDEWEB)

1957-06-21

The May, 1957 monthly report for the Chemical Processing Department of the Hanford Atomic Products Operation includes information regarding research and engineering efforts with respect to the Purex and Redox process technology. Also discussed is the production operation, finished product operation, power and general maintenance, financial operation, engineering and research operations, and employee operation.(MB)

Chemical Processing Department monthly report, September 1957

Energy Technology Data Exchange (ETDEWEB)

1957-10-22

The September, 1957 monthly report for the Chemical Processing Department of the Hanford Atomic Products Operation includes information regarding research and engineering efforts with respect to the Purex and Redox process technology. Also discussed is the production operation, finished product operation, power and general maintenance, financial operation, engineering and research operations, and employee operation.

Adsorption and Pore of Physical-Chemical Activated Coconut Shell Charcoal Carbon

Science.gov (United States)

Budi, E.; Umiatin, U.; Nasbey, H.; Bintoro, R. A.; Wulandari, Fi; Erlina, E.

2018-04-01

The adsorption of activated carbon of coconut shell charcoal on heavy metals (Cu and Fe) of the wastewater and its relation with the carbon pore structure was investigated. The coconut shell was pyrolized in kiln at temperature about 75 - 150 °C for about 6 hours to produce charcoal and then shieved into milimeter sized granule particles. Chemical activation was done by immersing the charcoal into chemical solution of KOH, NaOH, HCl and H3PO4, with various concentration. The activation was followed by physical activation using horizontal furnace at 400°C for 1 hours in argon gas environment with flow rate of 200 kg/m3. The surface morphology of activated carbon were characterized by using Scanning Electron Microscopy (SEM). Wastewater was made by dissolving CuSO4.5H2O and FeSO4.7H2O into aquades. The metal adsorption was analized by using Atomic Absorption Spectroscopy (AAS). The result shows that in general, the increase of chemical concentration cause the increase of pore number of activated carbon due to an excessive chemical attack and lead the increase of adsorption. However it tend to decrease as further increasing in chemical activator concentration due to carbon collapsing. In general, the adsorption of Cu and Fe metal from wastewater by activated carbon increased as the activator concentration was increased.

Modern techniques of sea level measurement

Digital Repository Service at National Institute of Oceanography (India)

Joseph, A.

stream_size 32 stream_content_type text/plain stream_name Encyclopedia_Microcomput_1999_23_319.pdf.txt stream_source_info Encyclopedia_Microcomput_1999_23_319.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset...

Analysis of Chemical Warfare Agents: General Overview, LC-MS Review, In-House LC-ESI-MS Methods and Open Literature Bibliography

National Research Council Canada - National Science Library

D'Agostino, Paul A; Chenier, C. L

2006-01-01

Ratification of the Chemical Weapons Convention by more than 165 States Parties has reduced the risk of chemical warfare agent use, but there still remains a concern that other parties may make use...

Chemical engineer in business; Kemikaru enjinia to bijinesu

Energy Technology Data Exchange (ETDEWEB)

Tsuchiya, Yasuaki

1999-05-05

It is Coca-Cola and General Electric Co. (GE) that the aggregate market value is drastically expanding in U.S.A. throughout over past of 15. Direct common point is not very much found to these 2 companies. During over of 15 years, the leadership was demonstrated as management top of both companies, 2 managers who drastically contributed to the enterprise value improvement are the chemical engineer graduate both. It does be not done either mere in which that both persons with the grounded ability of chemical engineering contributed to the enterprise value improvement of the dramatic was not accidental. It is the essence of the chemical engineering,'By discerning essence of the process, the appropriate countermeasure is passed' there was it for the basis of the management of both persons. (NEDO)

Lasers in chemical processing

International Nuclear Information System (INIS)

Davis, J.I.

1982-01-01

The high cost of laser energy is the crucial issue in any potential laser-processing application. It is expensive relative to other forms of energy and to most bulk chemicals. We show those factors that have previously frustrated attempts to find commercially viable laser-induced processes for the production of materials. Having identified the general criteria to be satisfied by an economically successful laser process and shown how these imply the laser-system requirements, we present a status report on the uranium laser isotope separation (LIS) program at the Lawrence Livermore National Laboratory

Natural remedies in the Canon of Medicine for dentistry and oral biology

Directory of Open Access Journals (Sweden)

Pouya Faridi

2015-03-01

Full Text Available Ibn Sina is one of the most well know scholars in middle ages. This Persian physician wrote different books in medical filed which his great encyclopedia remained as one the most successful medical encyclopedia during the history. Ibn Sina discussed diseases of oral cavity and dentistry in the 3rd book of The Canon of Medicine. He discussed different conditions such as different types of trauma to the motor nerves, taste sensation, different limitations of tongue movements, Ranula, halitosis, tooth sensation, different types of tooth pain, Bruxism, attrition, loss of enamel, gingival bleeding, recession and hyperplasia. For management of these diseases he introduced more than 80 herbal remedies. Most of this plant species are from essential oil reach families. Generally, Ibn Sina has a deep view in case of dental diseases and his ideas and methods for treatment of this category of disease could be studied for finding new treatment in dental ailments.

PREDICTION METRICS FOR CHEMICAL DETECTION IN LONG-WAVE INFRARED HYPERSPECTRAL IMAGERY

Energy Technology Data Exchange (ETDEWEB)

Chilton, M.; Walsh, S.J.; Daly, D.S.

2009-01-01

Natural and man-made chemical processes generate gaseous plumes that may be detected by hyperspectral imaging, which produces a matrix of spectra affected by the chemical constituents of the plume, the atmosphere, the bounding background surface and instrument noise. A physics-based model of observed radiance shows that high chemical absorbance and low background emissivity result in a larger chemical signature. Using simulated hyperspectral imagery, this study investigated two metrics which exploited this relationship. The objective was to explore how well the chosen metrics predicted when a chemical would be more easily detected when comparing one background type to another. The two predictor metrics correctly rank ordered the backgrounds for about 94% of the chemicals tested as compared to the background rank orders from Whitened Matched Filtering (a detection algorithm) of the simulated spectra. These results suggest that the metrics provide a reasonable summary of how the background emissivity and chemical absorbance interact to produce the at-sensor chemical signal. This study suggests that similarly effective predictors that account for more general physical conditions may be derived.

Voluntary cleanup of the Ames chemical disposal site

International Nuclear Information System (INIS)

Taboas, A.L.; Freeman, R.; Peterson, J.

2003-01-01

The U.S. Department of Energy completed a voluntary removal action at the Ames chemical disposal site, a site associated with the early days of the Manhattan Project. It contained chemical and low-level radioactive wastes from development of the technology to extract uranium from uranium oxide. The process included the preparation of a Remedial Investigation, Feasibility Study, Baseline Risk Assessment, and, ultimately, issuance of a Record of Decision. Various stakeholder groups were involved, including members of the regulatory community, the general public, and the landowner, Iowa State University. The site was restored and returned to the landowner for unrestricted use.

Journal of Chemical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Chemical Sciences; Volume 117; Issue 5. Generalized density-functional theory: Conquering the -representability problem with exact functionals for the electron pair density and the second-order reduced density matrix. Paul W Ayers Mel Levy. Volume 117 Issue 5 September 2005 pp 507-514 ...

75 FR 68972 - Medical Devices; General and Plastic Surgery Devices; Classification of Tissue Adhesive With...

Science.gov (United States)

2010-11-10

.... FDA-2010-N-0512] Medical Devices; General and Plastic Surgery Devices; Classification of Tissue... running to unintended areas, etc. B. Wound dehiscence C. Adverse tissue reaction and chemical burns D..., Clinical Studies, Labeling. Adverse tissue reaction and chemical Biocompatibility Animal burns. Testing...

Remote mapping of sea-surface currents using radiowave doppler radar systems

Digital Repository Service at National Institute of Oceanography (India)

Joseph, A.

stream_size 25 stream_content_type text/plain stream_name Encyclopedia_Microcomput_2000_24_Suppl-3_309.pdf.txt stream_source_info Encyclopedia_Microcomput_2000_24_Suppl-3_309.pdf.txt Content-Encoding ISO-8859-1 Content-Type text...

Mechanisms of chemical vapor generation by aqueous tetrahydridoborate. Recent developments toward the definition of a more general reaction model

Science.gov (United States)

D'Ulivo, Alessandro

2016-05-01

A reaction model describing the reactivity of metal and semimetal species with aqueous tetrahydridoborate (THB) has been drawn taking into account the mechanism of chemical vapor generation (CVG) of hydrides, recent evidences on the mechanism of interference and formation of byproducts in arsane generation, and other evidences in the field of the synthesis of nanoparticles and catalytic hydrolysis of THB by metal nanoparticles. The new "non-analytical" reaction model is of more general validity than the previously described "analytical" reaction model for CVG. The non-analytical model is valid for reaction of a single analyte with THB and for conditions approaching those typically encountered in the synthesis of nanoparticles and macroprecipitates. It reduces to the previously proposed analytical model under conditions typically employed in CVG for trace analysis (analyte below the μM level, borane/analyte ≫ 103 mol/mol, no interference). The non-analytical reaction model is not able to explain all the interference effects observed in CVG, which can be achieved only by assuming the interaction among the species of reaction pathways of different analytical substrates. The reunification of CVG, the synthesis of nanoparticles by aqueous THB and the catalytic hydrolysis of THB inside a common frame contribute to rationalization of the complex reactivity of aqueous THB with metal and semimetal species.

Evidence from pharmacology and pathophysiology suggests that chemicals with dissimilar mechanisms of action could be of bigger concern in the toxicological risk assessment of chemical mixtures than chemicals with a similar mechanism of action.

Science.gov (United States)

Hadrup, Niels

2014-08-01

Mathematical models have been developed for the toxicological risk assessment of chemical mixtures. However, exposure data as well as single chemical toxicological data are required for these models. When addressing this data need, it could be attractive to focus on chemicals with similar mechanisms of action, similar modes of action or with common target organs. In the European Union, efforts are currently being made to subgroup chemicals according to this need. However, it remains to be determined whether this is the best strategy to obtain data for risk assessment. In conditions such as cancer or HIV, it is generally recognised that pharmacological combination therapy targeting different mechanisms of action is more effective than a strategy where only one mechanism is targeted. Moreover, in diseases such as acute myocardial infarction and congestive heart failure, several organ systems concomitantly contribute to the pathophysiology, suggesting that a grouping based on common target organs may also be inefficient. A better option may be to prioritise chemicals on the basis of potency and risk of exposure. In conclusion, there are arguments to suggest that we should concomitantly consider all targets that a chemical can affect in the human body and not merely a subset. Copyright © 2014 Elsevier Inc. All rights reserved.

Atom interaction propensities of oxygenated chemical functions in crystal packings

Directory of Open Access Journals (Sweden)

Christian Jelsch

2017-03-01

Full Text Available The crystal contacts of several families of hydrocarbon compounds substituted with one or several types of oxygenated chemical groups were analyzed statistically using the Hirshfeld surface methodology. The propensity of contacts to occur between two chemical types is described with the contact enrichment descriptor. The systematic large enrichment ratios of some interactions like the O—H...O hydrogen bonds suggests that these contacts are a driving force in the crystal packing formation. The same statement holds for the weaker C—H...O hydrogen bonds in ethers, esters and ketones, in the absence of polar H atoms. The over-represented contacts in crystals of oxygenated hydrocarbons are generally of two types: electrostatic attractions (hydrogen bonds and hydrophobic interactions. While Cl...O interactions are generally avoided, in a minority of chloro-oxygenated hydrocarbons, significant halogen bonding does occur. General tendencies can often be derived for many contact types, but outlier compounds are instructive as they display peculiar or rare features. The methodology also allows the detection of outliers which can be structures with errors. For instance, a significant number of hydroxylated molecules displaying over-represented non-favorable oxygen–oxygen contacts turned out to have wrongly oriented hydroxyl groups. Beyond crystal packings with a single molecule in the asymmetric unit, the behavior of water in monohydrate compounds and of crystals with Z′ = 2 (dimers are also investigated. It was found in several cases that, in the presence of several oxygenated chemical groups, cross-interactions between different chemical groups (e.g. water/alcohols; alcohols/phenols are often favored in the crystal packings. While some trends in accordance with common chemical principles are retrieved, some unexpected results can however appear. For example, in crystals of alcohol–phenol compounds, the strong O—H...O hydrogen bonds between

Do Thyroid Disrupting Chemicals Influence Foetal Development during Pregnancy?

Science.gov (United States)

Hartoft-Nielsen, Marie-Louise; Boas, Malene; Bliddal, Sofie; Rasmussen, Åase Krogh; Main, Katharina; Feldt-Rasmussen, Ulla

2011-01-01

Maternal euthyroidism during pregnancy is crucial for normal development and, in particular, neurodevelopment of the foetus. Up to 3.5 percent of pregnant women suffer from hypothyroidism. Industrial use of various chemicals—endocrine disrupting chemicals (EDCs)—has been shown to cause almost constant exposure of humans with possible harmful influence on health and hormone regulation. EDCs may affect thyroid hormone homeostasis by different mechanisms, and though the effect of each chemical seems scarce, the added effects may cause inappropriate consequences on, for example, foetal neurodevelopment. This paper focuses on thyroid hormone influence on foetal development in relation to the chemicals suspected of thyroid disrupting properties with possible interactions with maternal thyroid homeostasis. Knowledge of the effects is expected to impact the general debate on the use of these chemicals. However, more studies are needed to elucidate the issue, since human studies are scarce. PMID:21918727

Processes for converting biomass-derived feedstocks to chemicals and liquid fuels

Science.gov (United States)

Held, Andrew; Woods, Elizabeth; Cortright, Randy; Gray, Matthew

2018-04-17

The present invention provides processes, methods, and systems for converting biomass-derived feedstocks to liquid fuels and chemicals. The method generally includes the reaction of a hydrolysate from a biomass deconstruction process with hydrogen and a catalyst to produce a reaction product comprising one of more oxygenated compounds. The process also includes reacting the reaction product with a condensation catalyst to produce C.sub.4+ compounds useful as fuels and chemicals.

Processes for converting biomass-derived feedstocks to chemicals and liquid fuels

Science.gov (United States)

Held, Andrew; Woods, Elizabeth; Cortright, Randy; Gray, Matthew

2017-05-23

The present invention provides processes, methods, and systems for converting biomass-derived feedstocks to liquid fuels and chemicals. The method generally includes the reaction of a hydrolysate from a biomass deconstruction process with hydrogen and a catalyst to produce a reaction product comprising one of more oxygenated compounds. The process also includes reacting the reaction product with a condensation catalyst to produce C.sub.4+ compounds useful as fuels and chemicals.

Monsoons, history of

Digital Repository Service at National Institute of Oceanography (India)

Niitsuma, N.; Naidu, P.D

stream_size 9 stream_content_type text/plain stream_name Encyclopedia_Ocean_Sci_3_1841.pdf.txt stream_source_info Encyclopedia_Ocean_Sci_3_1841.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset=ISO-8859-1 ...

Indian Ocean Islands, coastal ecology and geomorphology

Digital Repository Service at National Institute of Oceanography (India)

Wafar, M.V.M.; Wafar, S.; Yennavar, P.

stream_size 8 stream_content_type text/plain stream_name Encyclopedia_Coast_Sci_2005_557.pdf.txt stream_source_info Encyclopedia_Coast_Sci_2005_557.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset=ISO-8859-1 ...

Chemical Hazards and Safety Issues in Fusion Safety Design

International Nuclear Information System (INIS)

Cadwallader, L.C.

2003-01-01

Radiological inventory releases have dominated accident consequences for fusion; these consequences are important to analyze and are generally the most severe result of a fusion facility accident event. However, the advent of, or plan for, large-scale usage of some toxic materials poses the additional hazard of chemical exposure from an accident event. Examples of toxic chemicals are beryllium for magnetic fusion and fluorine for laser fusion. Therefore, chemical exposure consequences must also be addressed in fusion safety assessment. This paper provides guidance for fusion safety analysis. US Department of Energy (DOE) chemical safety assessment practices for workers and the public are reviewed. The US Environmental Protection Agency (EPA) has published some guidance on public exposure to releases of mixtures of chemicals, this guidance has been used to create an initial guideline for treating mixed radiological and toxicological releases in fusion; for example, tritiated hazardous dust from a tokamak vacuum vessel. There is no convenient means to judge the hazard severity of exposure to mixed materials. The chemical fate of mixed material constituents must be reviewed to determine if there is a separate or combined radiological and toxicological carcinogenesis, or if other health threats exist with radiological carcinogenesis. Recommendations are made for fusion facility chemical safety evaluation and safety guidance for protecting the public from chemical releases, since such levels are not specifically identified in the DOE fusion safety standard

Acoustic wave propagation in fluids with coupled chemical reactions

International Nuclear Information System (INIS)

Margulies, T.S.; Schwarz, W.H.

1984-08-01

This investigation presents a hydroacoustic theory which accounts for sound absorption and dispersion in a multicomponent mixture of reacting fluids (assuming a set of first-order acoustic equations without diffusion) such that several coupled reactions can occur simultaneously. General results are obtained in the form of a biquadratic characteristic equation (called the Kirchhoff-Langevin equation) for the complex propagation variable chi = - (α + iω/c) in which α is the attenuation coefficient, c is the phase speed of the progressive wave and ω is the angular frequency. Computer simulations of sound absorption spectra have been made for three different chemical systems, each comprised of two-step chemical reactions using physico-chemical data available in the literature. The chemical systems studied include: (1) water-dioxane, (2) aqueous solutions of glycine and (3) cobalt polyphosphate mixtures. Explicit comparisons are made between the exact biquadratic characteristic solution and the approximate equation (sometimes referred to as a Debye equation) previously applied to interpret the experimental data for the chemical reaction contribution to the absorption versus frequency. The relative chemical reaction and classical viscothermal contributions to the sound absorption are also presented. Several discrepancies that can arise when estimating thermodynamic data (chemical reaction heats or volume changes) for multistep chemical reaction systems when making dilute solution or constant density assumptions are discussed

Tri-metallic ferrite oxygen carriers for chemical looping combustion

Science.gov (United States)

Siriwardane, Ranjani V.; Fan, Yueying

2017-10-25

The disclosure provides a tri-metallic ferrite oxygen carrier for the chemical looping combustion of carbonaceous fuels. The tri-metallic ferrite oxygen carrier comprises Cu.sub.xFe.sub.yMn.sub.zO.sub.4-.delta., where Cu.sub.xFe.sub.yMn.sub.zO.sub.4-.delta. is a chemical composition. Generally, 0.5.ltoreq.x.ltoreq.2.0, 0.2.ltoreq.y.ltoreq.2.5, and 0.2.ltoreq.z.ltoreq.2.5, and in some embodiments, 0.8.ltoreq.x.ltoreq.1.2, y.ltoreq.1.2, and z.gtoreq.0.8. The tri-metallic ferrite oxygen carrier may be used in various applications for the combustion of carbonaceous fuels, including as an oxygen carrier for chemical looping combustion.

Radiation-chemical aspects of solid state hot atom chemistry

International Nuclear Information System (INIS)

Matsuura, T.; Collins, K.E.; Collins, C.H.

1984-01-01

The study of nuclear hot atom chemical (NHAC) processes occurring in solids is seriously limited by the lack of adequate methods for directly studying the chemical species containing hot atoms. In the present review the effects of ionizing radiation on parent and non-parent yields from solid state targets is surveyed and qualitative interpretations are given. After a few general remarks of the relationship of radiation chemistry to solid state NHAC, a detailed description of the radiation effects is given (radiation annealing, neutron activation, changes in separable yield). (Auth.)

Journal of Chemical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Chemical Sciences; Volume 125; Issue 1. Issue front cover thumbnail. Volume 125, Issue 1. January 2013, pages 7-211. pp 7-7. General Editorial on Publication Ethics · S S Krishnamurthy · More Details Fulltext PDF. pp 9-15. Redundant internal coordinates, compliance constants and ...

Microbial production of building block chemicals and polymers.

Science.gov (United States)

Lee, Jeong Wook; Kim, Hyun Uk; Choi, Sol; Yi, Jongho; Lee, Sang Yup

2011-12-01

Owing to our increasing concerns on the environment, climate change, and limited natural resources, there has recently been considerable effort exerted to produce chemicals and materials from renewable biomass. Polymers we use everyday can also be produced either by direct fermentation or by polymerization of monomers that are produced by fermentation. Recent advances in metabolic engineering combined with systems biology and synthetic biology are allowing us to more systematically develop superior strains and bioprocesses for the efficient production of polymers and monomers. Here, we review recent trends in microbial production of building block chemicals that can be subsequently used for the synthesis of polymers. Also, recent successful cases of direct one-step production of polymers are reviewed. General strategies for the production of natural and unnatural platform chemicals are described together with representative examples. Copyright © 2011 Elsevier Ltd. All rights reserved.

Chemical markers for the quality control of herbal medicines: an overview

Directory of Open Access Journals (Sweden)

Lung Cheng Chuen

2008-06-01

Full Text Available Abstract Selection of chemical markers is crucial for the quality control of herbal medicines, including authentication of genuine species, harvesting the best quality raw materials, evaluation of post-harvesting handling, assessment of intermediates and finished products, and detection of harmful or toxic ingredients. Ideal chemical markers should be the therapeutic components of herbal medicines. However, for most herbal medicines, the therapeutic components have not been fully elucidated or easily monitored. Bioactive, characteristic, main, synergistic, correlative, toxic and general components may be selected. This article reviews the effective use of chemical markers in the quality control of herbal medicines including the selection criteria considering the roles and physicochemical factors which may affect the effective use of chemical markers.

Chemical potential and the gap equation

International Nuclear Information System (INIS)

Chen Huan; Yuan Wei; Chang Lei; Liu Yuxin; Klaehn, Thomas; Roberts, Craig D.

2008-01-01

In general, the kernel of QCD's gap equation possesses a domain of analyticity upon which the equation's solution at nonzero chemical potential is simply obtained from the in-vacuum result through analytic continuation. On this domain the single-quark number- and scalar-density distribution functions are μ independent. This is illustrated via two models for the gap equation's kernel. The models are alike in concentrating support in the infrared. They differ in the form of the vertex, but qualitatively the results are largely insensitive to the Ansatz. In vacuum both models realize chiral symmetry in the Nambu-Goldstone mode, and in the chiral limit, with increasing chemical potential, they exhibit a first-order chiral symmetry restoring transition at μ≅M(0), where M(p 2 ) is the dressed-quark mass function.

A reaction-based paradigm to model reactive chemical transport in groundwater with general kinetic and equilibrium reactions

International Nuclear Information System (INIS)

Zhang, Fan; Yeh, Gour-Tsyh; Parker, Jack C.; Brooks, Scott C; Pace, Molly; Kim, Young Jin; Jardine, Philip M.; Watson, David B.

2007-01-01

This paper presents a reaction-based water quality transport model in subsurface flow systems. Transport of chemical species with a variety of chemical and physical processes is mathematically described by M. partial differential equations (PDEs). Decomposition via Gauss-Jordan column reduction of the reaction network transforms M. species reactive transport equations into two sets of equations: a set of thermodynamic equilibrium equations representing NE equilibrium reactions and a set of reactive transport equations of M-NE kinetic-variables involving no equilibrium reactions (a kinetic-variable is a linear combination of species). The elimination of equilibrium reactions from reactive transport equations allows robust and efficient numerical integration. The model solves the PDEs of kinetic-variables rather than individual chemical species, which reduces the number of reactive transport equations and simplifies the reaction terms in the equations. A variety of numerical methods are investigated for solving the coupled transport and reaction equations. Simulation comparisons with exact solutions were performed to verify numerical accuracy and assess the effectiveness of various numerical strategies to deal with different application circumstances. Two validation examples involving simulations of uranium transport in soil columns are presented to evaluate the ability of the model to simulate reactive transport with complex reaction networks involving both kinetic and equilibrium reactions

A reaction-based paradigm to model reactive chemical transport in groundwater with general kinetic and equilibrium reactions.

Science.gov (United States)

Zhang, Fan; Yeh, Gour-Tsyh; Parker, Jack C; Brooks, Scott C; Pace, Molly N; Kim, Young-Jin; Jardine, Philip M; Watson, David B

2007-06-16

This paper presents a reaction-based water quality transport model in subsurface flow systems. Transport of chemical species with a variety of chemical and physical processes is mathematically described by M partial differential equations (PDEs). Decomposition via Gauss-Jordan column reduction of the reaction network transforms M species reactive transport equations into two sets of equations: a set of thermodynamic equilibrium equations representing N(E) equilibrium reactions and a set of reactive transport equations of M-N(E) kinetic-variables involving no equilibrium reactions (a kinetic-variable is a linear combination of species). The elimination of equilibrium reactions from reactive transport equations allows robust and efficient numerical integration. The model solves the PDEs of kinetic-variables rather than individual chemical species, which reduces the number of reactive transport equations and simplifies the reaction terms in the equations. A variety of numerical methods are investigated for solving the coupled transport and reaction equations. Simulation comparisons with exact solutions were performed to verify numerical accuracy and assess the effectiveness of various numerical strategies to deal with different application circumstances. Two validation examples involving simulations of uranium transport in soil columns are presented to evaluate the ability of the model to simulate reactive transport with complex reaction networks involving both kinetic and equilibrium reactions.

Hazard assessment and risk management of offshore production chemicals

International Nuclear Information System (INIS)

Schobben, H.P.M.; Scholten, M.C.T.; Vik, E.A.; Bakke, S.

1994-01-01

There is a clear need for harmonization of the regulations with regard to the use and discharge of drilling and production chemicals in the North Sea. Therefore the CHARM (Chemical Hazard Assessment and Risk Management) model was developed. Both government (of several countries) and industry (E and P and chemical suppliers) participated in the project. The CHARM model is discussed and accepted by OSPARCON. The CHARM model consists of several modules. The model starts with a prescreening on the basis of hazardous properties like persistency, accumulation potential and the appearance on black lists. The core of the model.consists of modules for hazard assessment and risk analysis. Hazard assessment covers a general environmental evaluation of a chemical on the basis of intrinsic properties of that chemical. Risk analysis covers a more specific evaluation of the environmental impact from the use of a production chemical, or a combination of chemicals, under actual conditions. In the risk management module the user is guided to reduce the total risk of all chemicals used on a platform by the definition of measures in the most cost-effective way. The model calculates the environmental impact for the marine environment. Thereto three parts are distinguished: pelagic, benthic and food chain. Both hazard assessment and risk analysis are based on a proportional comparison of an estimated PEC with an estimated NEC. The PEC is estimated from the use, release, dilution and fate of the chemical and the NEC is estimated from the available toxicity data of the chemicals

Generalized Warburg impedance on realistic self-affine fractals ...

Indian Academy of Sciences (India)

Administrator

Generalized Warburg impedance on realistic self-affine fractals: Comparative study of statistically corrugated and isotropic roughness. RAJESH KUMAR and RAMA KANT. Journal of Chemical Sciences, Vol. 121, No. 5, September 2009, pp. 579–588. 1. ( ) c. L. R ω on page 582, column 2, para 2, after eq (8) should read as ...

Comparative enhancing effects of electret with chemical enhancers on transdermal delivery of meloxicam in vitro

International Nuclear Information System (INIS)

Cui, L L; Hou, X M; Li, G D; Jiang, J; Liang, Y Y; Xin, X

2008-01-01

Electret offers enhancing effect in transdermal drug delivery for altering of the arrangement of lipid molecules in the stratum corneum, forming many transient permeable apertures and enhancing the transdermal drug delivery. In this paper, meloxicam patch formulations were developed to make the comparative study of transdermal drug delivery between electret and chemical enhancers. Patches were made into control, electret, chemical enhancer and electret with chemical enhancer ones, according to the preparation procedure. The electret combined with chemical enhancer patch was designed to probe the incorporation between electret and chemical enhancer in transdermal drug delivery. The meloxicam release from the patch was found to increase in order of blank, chemical enhancer, electret and electret with chemical enhancer patch, in general.

Radiation chemical dosimetry by means of nitrate-nitrite

International Nuclear Information System (INIS)

Tormo Ferrero, M.J.

1977-01-01

The different chemical systems used in dosimetry and the selection criteria for them are described. The general topics in dosimetry with alkali nitrates as well as the phenomena occurring in their radiolisis are also treated. The possibility of application in dosimetric areas useful in radiosterilization and industrial processes is studied too. (author) [es

Carbon Footprint Calculations: An Application of Chemical Principles

Science.gov (United States)

Treptow, Richard S.

2010-01-01

Topics commonly taught in a general chemistry course can be used to calculate the quantity of carbon dioxide emitted into the atmosphere by various human activities. Each calculation begins with the balanced chemical equation for the reaction that produces the CO[subscript 2] gas. Stoichiometry, thermochemistry, the ideal gas law, and dimensional…

Quality of Life in Iranian Chemical Warfare Veteran's.

Science.gov (United States)

Ebadi, Abbas; Moradian, Tayeb; Mollahadi, Mohsen; Saeed, Yaser; Refahi, Ali Akbar

2014-05-01

Mustard gas has different effects on different body systems such as respiratory tract, blood, gastrointestinal, skin, eye, endocrine and peripheral nervous system. The purpose of this study was to determine the quality of life in chemical warfare veterans due to sulfur mustard exposure. In a cross-sectional and analytic study, 242 patients who had a chemical injury during the Iran-Iraq war (1980-1983) and their lung damage was proven were investigated in our study. The quality of life was measured in these patients using an extensively validated Iranian version of SF-36. The mean age of veterans was 44.12 ± 4.9 ranging from 22 to 62 years. Our results showed that chemical warfare had a decreased quality of life in all subscales of the SF-36. The lowest scores in SF-36 subscales were related to role physical and general health. The data also showed a significant relationship between the number of organs involved and the quality of life in these patients (P chemical warfare survivors suffering from late complications have a low health related quality of life.

Sample Preparation and Identification of Biological, Chemical and Mid-Spectrum Agents

National Research Council Canada - National Science Library

Hancock, J. R; Dragon, D. C

2005-01-01

A general survey of sample preparation and identification techniques for biological, chemical and mid-spectrum agents was conducted as part of Canada's contribution to a joint NATO Allied Engineering Publication (AEP) handbook...

Ionic Diffusion and Kinetic Homogeneous Chemical Reactions in the Pore Solution of Porous Materials with Moisture Transport

DEFF Research Database (Denmark)

Johannesson, Björn

2009-01-01

Results from a systematic continuum mixture theory will be used to establish the governing equations for ionic diffusion and chemical reactions in the pore solution of a porous material subjected to moisture transport. The theory in use is the hybrid mixture theory (HMT), which in its general form......’s law of diffusion and the generalized Darcy’s law will be used together with derived constitutive equations for chemical reactions within phases. The mass balance equations for the constituents and the phases together with the constitutive equations gives the coupled set of non-linear differential...... general description of chemical reactions among constituents is described. The Petrov – Galerkin approach are used in favour of the standard Galerkin weighting in order to improve the solution when the convective part of the problem is dominant. A modified type of Newton – Raphson scheme is derived...

Predicting carcinogenicity of diverse chemicals using probabilistic neural network modeling approaches

Energy Technology Data Exchange (ETDEWEB)

Singh, Kunwar P., E-mail: kpsingh_52@yahoo.com [Academy of Scientific and Innovative Research, Council of Scientific and Industrial Research, New Delhi (India); Environmental Chemistry Division, CSIR-Indian Institute of Toxicology Research, Post Box 80, Mahatma Gandhi Marg, Lucknow 226 001 (India); Gupta, Shikha; Rai, Premanjali [Academy of Scientific and Innovative Research, Council of Scientific and Industrial Research, New Delhi (India); Environmental Chemistry Division, CSIR-Indian Institute of Toxicology Research, Post Box 80, Mahatma Gandhi Marg, Lucknow 226 001 (India)

2013-10-15

Robust global models capable of discriminating positive and non-positive carcinogens; and predicting carcinogenic potency of chemicals in rodents were developed. The dataset of 834 structurally diverse chemicals extracted from Carcinogenic Potency Database (CPDB) was used which contained 466 positive and 368 non-positive carcinogens. Twelve non-quantum mechanical molecular descriptors were derived. Structural diversity of the chemicals and nonlinearity in the data were evaluated using Tanimoto similarity index and Brock–Dechert–Scheinkman statistics. Probabilistic neural network (PNN) and generalized regression neural network (GRNN) models were constructed for classification and function optimization problems using the carcinogenicity end point in rat. Validation of the models was performed using the internal and external procedures employing a wide series of statistical checks. PNN constructed using five descriptors rendered classification accuracy of 92.09% in complete rat data. The PNN model rendered classification accuracies of 91.77%, 80.70% and 92.08% in mouse, hamster and pesticide data, respectively. The GRNN constructed with nine descriptors yielded correlation coefficient of 0.896 between the measured and predicted carcinogenic potency with mean squared error (MSE) of 0.44 in complete rat data. The rat carcinogenicity model (GRNN) applied to the mouse and hamster data yielded correlation coefficient and MSE of 0.758, 0.71 and 0.760, 0.46, respectively. The results suggest for wide applicability of the inter-species models in predicting carcinogenic potency of chemicals. Both the PNN and GRNN (inter-species) models constructed here can be useful tools in predicting the carcinogenicity of new chemicals for regulatory purposes. - Graphical abstract: Figure (a) shows classification accuracies (positive and non-positive carcinogens) in rat, mouse, hamster, and pesticide data yielded by optimal PNN model. Figure (b) shows generalization and predictive

Chemical Peels

Science.gov (United States)

... care Kids’ zone Video library Find a dermatologist Chemical peels Overview Chemical peels: Overview Also called chemexfoliation , derma peeling Do ... Overview Chemical peels: FAQs Chemical peels: Preparation FAQs Chemical peels: FAQs To help you decide whether this ...

Nonlinear magnetoacoustic wave propagation with chemical reactions

Science.gov (United States)

Margulies, Timothy Scott

2002-11-01

The magnetoacoustic problem with an application to sound wave propagation through electrically conducting fluids such as the ocean in the Earth's magnetic field, liquid metals, or plasmas has been addressed taking into account several simultaneous chemical reactions. Using continuum balance equations for the total mass, linear momentum, energy; as well as Maxwell's electrodynamic equations, a nonlinear beam equation has been developed to generalize the Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation for a fluid with linear viscosity but nonlinear and diffraction effects. Thermodynamic parameters are used and not tailored to only an adiabatic fluid case. The chemical kinetic equations build on a relaxing media approach presented, for example, by K. Naugolnukh and L. Ostrovsky [Nonlinear Wave Processes in Acoustics (Cambridge Univ. Press, Cambridge, 1998)] for a linearized single reaction and thermodynamic pressure equation of state. Approximations for large and small relaxation times and for magnetohydrodynamic parameters [Korsunskii, Sov. Phys. Acoust. 36 (1990)] are examined. Additionally, Cattaneo's equation for heat conduction and its generalization for a memory process rather than a Fourier's law are taken into account. It was introduced for the heat flux depends on the temperature gradient at an earlier time to generate heat pulses of finite speed.

History of Mathematics

DEFF Research Database (Denmark)

Hansen, Vagn Lundsgaard; Gray, Jeremy

Volume 1 in Theme on "History of Mathematics", in "Encyclopedia of Life Support Systems (EOLSS), developed under the auspices of the UNESCO.......Volume 1 in Theme on "History of Mathematics", in "Encyclopedia of Life Support Systems (EOLSS), developed under the auspices of the UNESCO....

Journal of Chemical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Chemical Sciences; Volume 128; Issue 1. Issue front cover thumbnail. Volume 128, Issue 1. January 2016, pages a-164. pp a-d. Contents · More Details Fulltext PDF. pp e-e. General Editorial on Publication Ethics · More Details Fulltext PDF. pp 1-8 Regular Articles. Design and synthesis of ...

Radiation chemical dosimetry by means of nitrate-nitrite

International Nuclear Information System (INIS)

Tormo Ferrero, M. J.

1977-01-01

The different chemical systems used in dosimetry and the selection criteria for them are described. The general topics in dosimetry with alkali nitrates as well as the phenomena occurring in their radiolysis are also treated. The possibility of application in dosimetric areas useful in radiosterilization and industrial processes is studied too. (Author) 22 refs

Advanced chemical analysis service for elements, radionuclides and phases

International Nuclear Information System (INIS)

Sansoni, B.

1986-01-01

A review is given on the structure, organisation and performance of the chemical analysis service of the Central Department for Chemical Analysis at the Kernforschungsanlage Juelich GmbH. The research and development programs together with the infrastructure of the Centre afford to analyse almost all stable elements of the periodical table in almost any material. The corresponding chemical analysis service has been organized according to a new modular system of analytical steps. According to this, the most complicated and, therefore, most general case of an analytical scheme for element and radionuclide analysis in any type of material can be differentiated into about 14 different steps, the modules. They are more or less independent of the special problem. The laboratory is designed and organized according to these steps. (orig./PW) [de

On the Chemical Mixing Induced by Internal Gravity Waves

Energy Technology Data Exchange (ETDEWEB)

Rogers, T. M. [School of Mathematics, Statistics and Physics, Newcastle University, Newcastle upon Tyne (United Kingdom); McElwaine, J. N. [Planetary Science Institute, Tucson, AZ 85721 (United States)

2017-10-10

Detailed modeling of stellar evolution requires a better understanding of the (magneto)hydrodynamic processes that mix chemical elements and transport angular momentum. Understanding these processes is crucial if we are to accurately interpret observations of chemical abundance anomalies, surface rotation measurements, and asteroseismic data. Here, we use two-dimensional hydrodynamic simulations of the generation and propagation of internal gravity waves in an intermediate-mass star to measure the chemical mixing induced by these waves. We show that such mixing can generally be treated as a diffusive process. We then show that the local diffusion coefficient does not depend on the local fluid velocity, but rather on the wave amplitude. We then use these findings to provide a simple parameterization for this diffusion, which can be incorporated into stellar evolution codes and tested against observations.

De Novo Assembly and Transcriptome Analysis of Wheat with Male Sterility Induced by the Chemical Hybridizing Agent SQ-1.

Directory of Open Access Journals (Sweden)

Qidi Zhu

Full Text Available Wheat (Triticum aestivum L., one of the world's most important food crops, is a strictly autogamous (self-pollinating species with exclusively perfect flowers. Male sterility induced by chemical hybridizing agents has increasingly attracted attention as a tool for hybrid seed production in wheat; however, the molecular mechanisms of male sterility induced by the agent SQ-1 remain poorly understood due to limited whole transcriptome data. Therefore, a comparative analysis of wheat anther transcriptomes for male fertile wheat and SQ-1-induced male sterile wheat was carried out using next-generation sequencing technology. In all, 42,634,123 sequence reads were generated and were assembled into 82,356 high-quality unigenes with an average length of 724 bp. Of these, 1,088 unigenes were significantly differentially expressed in the fertile and sterile wheat anthers, including 643 up-regulated unigenes and 445 down-regulated unigenes. The differentially expressed unigenes with functional annotations were mapped onto 60 pathways using the Kyoto Encyclopedia of Genes and Genomes database. They were mainly involved in coding for the components of ribosomes, photosynthesis, respiration, purine and pyrimidine metabolism, amino acid metabolism, glutathione metabolism, RNA transport and signal transduction, reactive oxygen species metabolism, mRNA surveillance pathways, protein processing in the endoplasmic reticulum, protein export, and ubiquitin-mediated proteolysis. This study is the first to provide a systematic overview comparing wheat anther transcriptomes of male fertile wheat with those of SQ-1-induced male sterile wheat and is a valuable source of data for future research in SQ-1-induced wheat male sterility.

Endocrine-disrupting chemicals and obesity development in humans: A review

DEFF Research Database (Denmark)

Tang-Péronard, Jeanett; Andersen, Helle Raun; Jensen, Tina Kold

2011-01-01

This study reviewed the literature on the relations between exposure to chemicals with endocrine-disrupting abilities and obesity in humans. The studies generally indicated that exposure to some of the endocrine-disrupting chemicals was associated with an increase in body size in humans...... dibenzofurans found either associations with weight gain or an increase in waist circumference, or no association. The one study investigating relations with bisphenol A found no association. Studies investigating prenatal exposure indicated that exposure in utero may cause permanent physiological changes...

Some general requirements for irradiation experiments

Energy Technology Data Exchange (ETDEWEB)

Myers, H P; Skjoeldebrand, R

1960-05-15

This paper is limited to the interests of the EAES-symposium, namely the use of reactors for materials research and testing, for convenience we exclude consideration of chemical effects and problems of coolant technology. Its purpose is to try to define the general requirements for irradiation experiments and the reactors housing them; to see what facilities for irradiation experiments are available within the European Atomic Energy Society countries and finally, to point out possible limitations of these facilities.

Chemical behavior of phthalates under abiotic conditions in landfills.

Science.gov (United States)

Huang, Jingyu; Nkrumah, Philip N; Li, Yi; Appiah-Sefah, Gloria

2013-01-01

The phthalates comprise a family of phthalic acid esters that are used primarily as plasticizers in polymeric materials to impart flexibility during the manufacturing process and to the end product. It is estimated that the annual worldwide production of phthalate esters exceeds five million tons. Plasticizers are one of the most prominent classes of chemicals, but unfortunately, they possess endocrine-disrupting chemical properties. As endocrine-disrupting chemicals, plasticizers have produced adverse developmental and reproductive effects in mammalian animal models.Phthalates are easily transported into the environment during manufacture, disposal,and leaching from plastic materials, because they are not covalently bound to the plastics of which they are a component. Because of their fugitive nature and widespread use, the phthalates are commonly detected in air, water, sediment/soil, and biota, including human tissue. Large amounts of phthalic acid esters are often leached from the plastics that are dumped at municipal landfills.Phthalate esters undergo chemical changes when released into the environment.The primary processes by which they are transformed include hydrolysis, photolysis,and biodegradation. It is noteworthy that all of these degradation processes are greatly influenced by the local physical and chemical conditions. Hence, in the present review, we have sought to ascertain from the literature how the phthalate esters undergo transformation when they are released into lower landfill layers.Within the upper landfill layers, biodegradation prevails as the major degradation mechanism by which the phthalates are dissipated. Generally, biodegradation pathways for the phthalates consist of primary biodegradation from phthalate diesters to phthalate monoesters, then to phthalic acid, and ultimately biodegradation of phthalic acid to form C02 and/or CH4• We have noted that the phthalate esters are also degraded through abiotic means,which proceeds via

Knowledge and the Systematic Reader: The Past and Present of Encyclopedic Learning

Directory of Open Access Journals (Sweden)

Seth Rudy

2014-06-01

Full Text Available Though digital media have unquestionably affected the features and functions of modern encyclopedias, such works also continue to be shaped by factors thoroughly conventional by the end of the historical Enlightenment. As William Smellie, editor of the first Encyclopedia Britannica (1768-71 wrote, "utility ought to be the principal intention of every publication. Wherever this intention does not plainly appear, neither the books nor their authors have the smallest claim to the approbation of mankind." The "instructional designers" and "user-experience specialists" of the online Britannica are the inheritors of all those au-thors and editors who before and after Smellie's time devised different plans and methods intended to maximize the utility of their works. The definition of utility and with it the nature of encyclopedic knowledge continues to change both because of and despite technological difference; if digitization has in some ways advanced the ideals of Enlightenment encyclopedias, then it has in other ways allowed for the re-inscription of certain flaws and limitations that encyclopedias like the Britannica were specifically designed to overcome. By examining not only what one might read in the encyclopedia but also the ways in which one might read it, this article demonstrates the extent to which the notion of encyclopedic utility depends on historical context.

Annual Report 1998: Chemical Structure and Dynamics

Energy Technology Data Exchange (ETDEWEB)

SD Colson; RS McDowell

1999-05-10

The Chemical Structure and Dynamics (CS&D) program is a major component of the William R. Wiley Environmental Molecular Sciences Labo- ratory (EMSL), developed by Pacific Northwest National Laboratory (PNNL) to provide a state-of- the-art collaborative facility for studies of chemical structure and dynamics. We respond to the need for a fundamental, molecular-level understanding of chemistry at a wide variety of environmentally important interfaces by (1) extending the experimental characterization and theoretical description of chemical reactions to encompass the effects of condensed media and interfaces; (2) developing a multidisciplinary capability for describing interracial chemical processes within which the new knowledge generated can be brought to bear on complex phenomena in envi- ronmental chemistry and in nuclear waste proc- essing and storage; and (3) developing state-of- the-art analytical methods for characterizing com- plex materials of the types found in stored wastes and contaminated soils, and for detecting and monitoring trace atmospheric species. Our program aims at achieving a quantitative understanding of chemical reactions at interfaces and, more generally, in condensed media, compa- rable to that currently available for gas-phase reactions. This understanding will form the basis for the development of a priori theories for pre- dicting macroscopic chemical behavior in con- densed and heterogeneous media, which will add significantly to the value of field-scale envi- ronmental models, predictions of short- and long- term nuclear waste storage stabilities, and other areas related to the primary missions of the U.S. Department of Energy (DOE).

A general method for the inclusion of radiation chemistry in astrochemical models.

Science.gov (United States)

Shingledecker, Christopher N; Herbst, Eric

2018-02-21

In this paper, we propose a general formalism that allows for the estimation of radiolysis decomposition pathways and rate coefficients suitable for use in astrochemical models, with a focus on solid phase chemistry. Such a theory can help increase the connection between laboratory astrophysics experiments and astrochemical models by providing a means for modelers to incorporate radiation chemistry into chemical networks. The general method proposed here is targeted particularly at the majority of species now included in chemical networks for which little radiochemical data exist; however, the method can also be used as a starting point for considering better studied species. We here apply our theory to the irradiation of H 2 O ice and compare the results with previous experimental data.

Encyclopedia of two-phase heat transfer and flow II special topics and applications

CERN Document Server

Kim, Jungho

2015-01-01

The aim of the two–set series is to present a very detailed and up–to–date reference for researchers and practicing engineers in the fields of mechanical, refrigeration, chemical, nuclear and electronics engineering on the important topic of two-phase heat transfer and two-phase flow. The scope of the first set of 4 volumes presents the fundamentals of the two-phase flows and heat transfer mechanisms, and describes in detail the most important prediction methods, while the scope of the second set of 4 volumes presents numerous special topics and numerous applications, also including numerical simulation methods. Practicing engineers will find extensive coverage to applications involving: multi-microchannel evaporator cold plates for electronics cooling, boiling on enhanced tubes and tube bundles, flow pattern based methods for predicting boiling and condensation inside horizontal tubes, pressure drop methods for singularies (U-bends and contractions), boiling in multiport tubes, and boiling and condens...

Activation analysis. A basis for chemical similarity and classification

Energy Technology Data Exchange (ETDEWEB)

Beeck, J OP de [Ghent Rijksuniversiteit (Belgium). Instituut voor Kernwetenschappen

1977-01-01

It is shown that activation analysis is especially suited to serve as a basis for determining the chemical similarity between samples defined by their trace-element concentration patterns. The general problem of classification and identification is discussed. The nature of possible classification structures and their appropriate clustering strategies is considered. A practical computer method is suggested and its application as well as the graphical representation of classification results are given. The possibility for classification using information theory is mentioned. Classification of chemical elements is discussed and practically realized after Hadamard transformation of the concentration variation patterns in a series of samples.

Production of chemical substances in Tajikistan

International Nuclear Information System (INIS)

Boboev, Kh.E.; Nazarov, K.M.

2010-01-01

Full text: Government of the Republic of Tajikistan has signed Convention "On prohibition of chemical weapon application"and no chemical weapon (CHW) is produced on the territory of republic. However, the potential production of CHW by individual persons or groups can be organized, using available production and obtaining chemical substances from other countries. Chemical substances, which have strong damage effect, easily, can be synthesized in chemical laboratories. These are general toxic substances, as hydrocyanic acid acid, phosgene, mustard gas, lewisite, sarin and others. The similar chemical substances of industrial significance are produced in Tajikistan: ammonia, chlorine, explosives, caustic soda, carbamide, formaldehyde and others. For industrial needs and agriculture from other countries Tajikistan is receiving the following: sodium cyanide and potassium for gold-mining; mineral acids; pesticides and others. Besides, there are different deposits in Tajikistan, reprocessing of which gives an opportunity to obtain different chemical substances. What can be obtained from chemicals produced in Tajikistan? Chlorine - from this reagent the fluoride chlorine, phosgene COCl_2 and many other compounds are easily synthesized, which are CHW components. Obtained cyanic compounds for gold mining can be used as precursor for neuroparalytic action. A big amount of metallic aluminum is produced in the republic. The Al powder for rocket fuel can be obtained from it. Obtained from other countries pesticides are potential components for CHW creation. A strong control and account of pesticides use is necessary. It is extremely important to control materials, equipment and technologies which allow countries and separate groups to create weapons of mass destruction (WMD). The most important factor is goods identification. Firstly - inspection of external view, labeling, packing specifications, license availability and etc. Strong control of checklists is necessary according

Eccentric connectivity index of chemical trees

International Nuclear Information System (INIS)

Haoer, R. S.; Atan, K. A.; Said, M. R. Md.; Khalaf, A. M.; Hasni, R.

2016-01-01

Let G = (V, E) be a simple connected molecular graph. In such a simple molecular graph, vertices and edges are depicted atoms and chemical bonds respectively, we refer to the sets of vertices by V (G) and edges by E (G). If d(u, v) be distance between two vertices u, v ∈ V(G) and can be defined as the length of a shortest path joining them. Then, the eccentricity connectivity index (ECI) of a molecular graph G is ξ(G) = ∑_v_∈_V_(_G_) d(v) ec(v), where d(v) is degree of a vertex v ∈ V(G). ec(v) is the length of a greatest path linking to another vertex of v. In this study, we focus the general formula for the eccentricity connectivity index (ECI) of some chemical trees as alkenes.

Exact effective action for (1+1)-dimensional fermions in an Abelian background at finite temperature and chemical potential

International Nuclear Information System (INIS)

Maciel, Soraya G.; Perez, Silvana

2008-01-01

In this paper we study the effects of a nonzero chemical potential in (1+1)-dimensional quantum field models at finite temperature. We particularly consider massless fermions in an Abelian gauge field background and calculate the effective action by evaluating the n-point functions. We find that the structure of the amplitudes corresponds to a generalization of the structure noted earlier in a calculation without a chemical potential (the associated integrals carry the dependence on the chemical potential). Our calculation shows that the chiral anomaly is unaffected by the presence of a chemical potential at finite temperature. However, unlike in the absence of a chemical potential, odd point functions do not vanish. We trace this to the fact that in the presence of a chemical potential the generalized charge conjugation symmetry of the theory allows for such amplitudes. In fact, we find that all the even point functions are even functions of μ, while the odd point functions are odd functions of μ which is consistent with this generalized charge conjugation symmetry. We show that the origin of the structure of the amplitudes is best seen from a formulation of the theory in terms of left- and right-handed spinors. The calculations are also much simpler in this formulation and it clarifies many other aspects of the theory.

Comparative Studies of Physico-chemical Properties of Some ...

African Journals Online (AJOL)

The aim of this study was to evaluate some physico-chemical properties of four major general purpose cement (As, Br, De and Sk) sold in Nigerian market using standard methods; due to the persistent collapse of buildings. The results showed that Br cement recorded the least CaO content (56.17%) while De cement had ...

Southern Gothic Literature

DEFF Research Database (Denmark)

Bjerre, Thomas Ærvold

2017-01-01

Provides an outline of Southern Gothic Literature, offers an argument about its history and shape, and discusses the scholarly literature surrounding Southern Gothic. Oxford Research Encyclopedia is an online peer-reviewed encyclopedia for researchers, teachers, and students interested in all...... facets of the study of literature...

Astronomy in the Digital Universe

Science.gov (United States)

Haisch, Bernard M.; Lindblom, J.; Terzian, Y.

2006-12-01

The Digital Universe is an Internet project whose mission is to provide free, accurate, unbiased information covering all aspects of human knowledge, and to inspire humans to learn, make use of, and expand this knowledge. It is planned to be a decades long effort, inspired by the Encyclopedia Galactica concept popularized by Carl Sagan, and is being developed by the non-profit Digital Universe Foundation. A worldwide network of experts is responsible for selecting content featured within the Digital Universe. The first publicly available content is the Encyclopedia of Earth, a Boston University project headed by Prof. Cutler Cleveland, which will be part of the Earth Portal. The second major content area will be an analogous Encyclopedia of the Cosmos to be part of the Cosmos Portal. It is anticipated that this will evolve into a major resource for astronomy education. Authors and topic editors are now being recruited for the Encyclopedia of the Cosmos.

Sensory systems II senses other than vision

CERN Document Server

Wolfe, Jeremy M

1988-01-01

This series of books, "Readings from the Encyclopedia of Neuroscience." consists of collections of subject-clustered articles taken from the Encyclopedia of Neuroscience. The Encyclopedia of Neuroscience is a reference source and compendium of more than 700 articles written by world authorities and covering all of neuroscience. We define neuroscience broadly as including all those fields that have as a primary goal the under­ standing of how the brain and nervous system work to mediate/control behavior, including the mental behavior of humans. Those interested in specific aspects of the neurosciences, particular subject areas or specialties, can of course browse through the alphabetically arranged articles of the En­ cyclopedia or use its index to find the topics they wish to read. However. for those readers-students, specialists, or others-who will find it useful to have collections of subject-clustered articles from the Encyclopedia, we issue this series of "Readings" in paperback. Students in neuroscienc...

40 CFR 270.14 - Contents of part B: General requirements.

Science.gov (United States)

2010-07-01

..., and engineering studies shall be certified by a qualified Professional Engineer. For post-closure... § 264.1 provides otherwise: (1) A general description of the facility. (2) Chemical and physical... atmosphere. (9) A description of precautions to prevent accidental ignition or reaction of ignitable...

Chemical aspects of nuclear waste treatment

International Nuclear Information System (INIS)

Bond, W.D.

1980-01-01

The chemical aspects of the treatment of gaseous, liquid, and solid wastes are discussed in overview. The role of chemistry and the chemical reactions in waste treatment are emphasized. Waste treatment methods encompass the chemistry of radioactive elements from every group of the periodic table. In most streams, the radioactive elements are present in relatively low concentrations and are often associated with moderately large amounts of process reagents, or materials. In general, it is desirable that waste treatment methods are based on chemistry that is selective for the concentration of radionuclides and does not require the addition of reagents that contribute significantly to the volume of the treated waste. Solvent extraction, ion exchange, and sorbent chemistry play a major role in waste treatment because of the high selectivity provided for many radionuclides. This paper deals with the chemistry of the onsite treatment methods that is typically used at nuclear installations and is not concerned with the chemistry of the various alternative materials proposed for long-term storage of nuclear wastes. The chemical aspects are discussed from a generic point of view in which the chemistry of important radionuclides is emphasized

Turbulent diffusion of chemically reacting flows: Theory and numerical simulations.

Science.gov (United States)

Elperin, T; Kleeorin, N; Liberman, M; Lipatnikov, A N; Rogachevskii, I; Yu, R

2017-11-01

The theory of turbulent diffusion of chemically reacting gaseous admixtures developed previously [T. Elperin et al., Phys. Rev. E 90, 053001 (2014)PLEEE81539-375510.1103/PhysRevE.90.053001] is generalized for large yet finite Reynolds numbers and the dependence of turbulent diffusion coefficient on two parameters, the Reynolds number and Damköhler number (which characterizes a ratio of turbulent and reaction time scales), is obtained. Three-dimensional direct numerical simulations (DNSs) of a finite-thickness reaction wave for the first-order chemical reactions propagating in forced, homogeneous, isotropic, and incompressible turbulence are performed to validate the theoretically predicted effect of chemical reactions on turbulent diffusion. It is shown that the obtained DNS results are in good agreement with the developed theory.

Building surface decontamination for chemical counter-terrorism

Energy Technology Data Exchange (ETDEWEB)

Harrison, S.; Thouin, G.; Kuang, W. [SAIC Canada, Ottawa, ON (Canada); Volchek, K.; Fingas, M.; Li, K. [Environment Canada, Ottawa, ON (Canada). Emergencies Science and Technology Division, Environmental Technology Centre, Science and Technology Branch

2006-07-01

A test method to compare and evaluate surface decontamination methods for buildings affected by chemical attacks was developed. Decontamination techniques generally depend on the nature and quantity of the weapon agent, the type of construction material and the location. Cleanup methods can be either physical, chemical or biological. This paper addressed chemical decontamination methods which use reactants to change the molecular structure of the contaminant. Peroxycarboxylic and peroxyacetic acids (PAA) are being used increasingly for both disinfection and environmental protection. In this study, 4 materials were chosen to represent common building materials. Samples were spiked with 10 mg of pesticides such as malathion and diazinon. Decontamination agents included the commercial decontamination agent CASCAD prepared in liquid form, a chemical preparation of PAA, and reagent grade peroxypropionic acid (PPA). The newly developed surface decontamination procedure can evaluate and compare the effectiveness of different chemical decontamination agents. The procedures were used on porous ceiling tile and carpet as well as on non-porous floor tile and painted steel surfaces. Rinse water was collected and analyzed in order to determine if decontamination was a result of chemical destruction or mechanical removal. The extraction efficiencies were found to be acceptable for all materials, with the exception of the highly porous ceiling tile. The extraction of diazinon from all surfaces was less efficient than the extraction of malathion. Results suggest that the performance of decontamination agents can be improved by repeated application of the decontamination agent, along with greater volumes and a combination of chemical and mechanical actions. It was also suggested that breakdown methods and wastewater treatment procedures should be developed because hazardous byproducts were detected in many samples. 18 refs., 1 tab., 17 figs.

Chemesthesis and the Chemical Senses as Components of a “Chemofensor Complex”

Science.gov (United States)

2012-01-01

An important function of the chemical senses is to warn against dangerous biological and chemical agents in the environment. The discovery in recent years of “taste” receptor cells outside the oral cavity that appear to have protective functions has raised new questions about the nature and scope of the chemical senses in general and of chemesthesis in particular. The present paper briefly reviews these findings within the context of what is currently known about the body's chemically sensitive protective mechanisms, including nonsensory processes that help to expel or neutralize threatening agents once they have been encountered. It is proposed that this array of defense mechanisms constitutes a “chemofensor complex” in which chemesthesis is the most ubiquitous, functionally diverse, and interactive chemosensory component. PMID:22210122

Two-scale large deviations for chemical reaction kinetics through second quantization path integral

International Nuclear Information System (INIS)

Li, Tiejun; Lin, Feng

2016-01-01

Motivated by the study of rare events for a typical genetic switching model in systems biology, in this paper we aim to establish the general two-scale large deviations for chemical reaction systems. We build a formal approach to explicitly obtain the large deviation rate functionals for the considered two-scale processes based upon the second quantization path integral technique. We get three important types of large deviation results when the underlying two timescales are in three different regimes. This is realized by singular perturbation analysis to the rate functionals obtained by the path integral. We find that the three regimes possess the same deterministic mean-field limit but completely different chemical Langevin approximations. The obtained results are natural extensions of the classical large volume limit for chemical reactions. We also discuss its implication on the single-molecule Michaelis–Menten kinetics. Our framework and results can be applied to understand general multi-scale systems including diffusion processes. (paper)

A General Chemistry Laboratory Course Designed for Student Discussion

Science.gov (United States)

Obenland, Carrie A.; Kincaid, Kristi; Hutchinson, John S.

2014-01-01

We report a study of the general chemistry laboratory course at one university over four years. We found that when taught as a traditional laboratory course, lab experiences do not encourage students to deepen their understanding of chemical concepts. Although the lab instructor emphasized that the lab experiences were designed to enhance…

9 CFR 318.15 - Tagging chemicals, preservatives, cereals, spices, etc., “U.S. retained.”

Science.gov (United States)

2010-01-01

..., cereals, spices, etc., âU.S. retained.â 318.15 Section 318.15 Animals and Animal Products FOOD SAFETY AND...; REINSPECTION AND PREPARATION OF PRODUCTS General § 318.15 Tagging chemicals, preservatives, cereals, spices, etc., “U.S. retained.” When any chemical, preservative, cereal, spice, or other substance is intended...

Book of abstracts Chemical Engineering: IV All-Russian Conference on chemical engineering, All-Russian Youth Conference on chemical engineering, All-Russian school on chemical engineering for young scientists and specialists. Chemical engineering of nanomaterials. Energy- and resource-saving chemical-engineering processes and problems of their intensification. Processes and apparatuses of chemical engineering, chemical cybernetics. Ecological problems of chemical engineering and related fields

International Nuclear Information System (INIS)

Zakhodyaeva, Yu.A.; Belova, V.V.

2012-01-01

In the given volume of abstracts of the IV All-Russian Conference on chemical engineering, All-Russian Youth Conference on chemical engineering, All-Russian school on chemical engineering for young scientists and specialists (Moscow, March 18-23, 2012) there are the abstracts of the reports concerning chemical engineering of nanomaterials, energy- and resource-saving chemical-engineering processes, processes and apparatuses of chemical engineering, chemical cybernetics, ecological problems of chemical engineering and related fields. The abstracts deal with state-of-the-art and future development of theoretical and experimental investigations as well as with experience in practical realization of development works in the field of chemical engineering and relative areas [ru

Effect of a Perturbation on the Chemical Equilibrium: Comparison with Le Chatelier's Principle

Science.gov (United States)

Torres, Emilio Martinez

2007-01-01

This article develops a general thermodynamic treatment to predict the direction of shift in a chemical equilibrium when it is subjected to a stress. This treatment gives an inequality that relates the change in the perturbed variable and the change that the equilibrium shift produces in the conjugated variable. To illustrate the generality of…

Instantaneous chemical profiles of banknotes by ambient mass spectrometry.

Science.gov (United States)

Eberlin, Livia S; Haddad, Renato; Sarabia Neto, Ramon C; Cosso, Ricardo G; Maia, Denison R J; Maldaner, Adriano O; Zacca, Jorge Jardim; Sanvido, Gustavo B; Romão, Wanderson; Vaz, Boniek G; Ifa, Demian R; Dill, Allison; Cooks, R Graham; Eberlin, Marcos N

2010-10-01

Using two desorption/ionization techniques (DESI and EASI) and Brazilian real, US$ dollar, and euro bills as proof-of-principle techniques and samples, direct analysis by ambient mass spectrometry is shown to function as an instantaneous, reproducible, and non-destructive method for chemical analysis of banknotes. Characteristic chemical profiles were observed for the authentic bills and for the counterfeit bills made using different printing processes (inkjet, laserjet, phaser and off-set printers). Detection of real-world counterfeit bills and identification of the counterfeiting method has also been demonstrated. Chemically selective 2D imaging of banknotes has also been used to confirm counterfeiting. The nature of some key diagnostic ions has also been investigated via high accuracy FTMS measurements. The general applicability of ambient MS analysis for anti-counterfeiting strategies particularly via the use of "invisible ink" markers is discussed.

Phase transitions at finite chemical potential in grand unified theories

International Nuclear Information System (INIS)

Bailin, D.; Love, A.

1984-01-01

We discuss the circumstances in which non-zero chemical potentials might prevent symmetry restoration in phase transitions in the early universe at grand unification or partial unification scales. The general arguments are illustrated by consideration of SO(10) and SU(5) grand unified theories. (orig.)

Improved inhalation technology for setting safe exposure levels for workplace chemicals

Science.gov (United States)

Stuart, Bruce O.

1993-01-01

Threshold Limit Values recommended as allowable air concentrations of a chemical in the workplace are often based upon a no-observable-effect-level (NOEL) determined by experimental inhalation studies using rodents. A 'safe level' for human exposure must then be estimated by the use of generalized safety factors in attempts to extrapolate from experimental rodents to man. The recent development of chemical-specific physiologically-based toxicokinetics makes use of measured physiological, biochemical, and metabolic parameters to construct a validated model that is able to 'scale-up' rodent response data to predict the behavior of the chemical in man. This procedure is made possible by recent advances in personal computer software and the emergence of appropriate biological data, and provides an analytical tool for much more reliable risk evaluation and airborne chemical exposure level setting for humans.

An encyclopedia on domestic electricity

International Nuclear Information System (INIS)

1982-12-01

This book describes the footprint of domestic electrification with domestic energy and the role of electrification, basic knowledge on domestic electrification, the basic things electric equipment in domestic, materials, part and making, demand of electricity, electrification and life, various electric equipment in the kitchen, rationalization of house chore, environment and hygiene like electric iron, electric stove, electric mat and dining wagon, beauty treatment and health, refinement and entertainment and lighting in houses.

Encyclopedia of earth system science

National Research Council Canada - National Science Library

Nierenberg, William Aaron

1992-01-01

.... The very diversity of the articles attests to the complexity of earth system science as a unique interdisciplinary venture to place humanity in a position to move wisely to protect the global habitat...

Nursing leadership: a concise encyclopedia

National Research Council Canada - National Science Library

Feldman, Harriet R

2008-01-01

... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xvii Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxv...

Nursing leadership: a concise encyclopedia

National Research Council Canada - National Science Library

Feldman, Harriet R

2008-01-01

... . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 569This page intentionally left blank List of EntriesList of Entries A Academic...

Chemical speciation modelling of groundwater in a shallow glacial sand aquifer part 1 General parameters

OpenAIRE

Falck, W.E.; Quinn, G.W.; Duffield, J.R.; Williams, D.R.

1988-01-01

The aim of the work detailed in this report has been to gain a better understanding of the speciation chemistry controlling the aqueous chemical forms of elements and compounds normally present in groundwaters found at the BGS in situ migration experiment at Drigg, Cumbria. This will form the basis of future modelling studies designed to interpret in situ tracer experiments using 60Co in the presence of naturally occurring organic complexants. Total element concentrations in re...

Chemical structure and dynamics. Annual report 1994

Energy Technology Data Exchange (ETDEWEB)

Colson, S.D.

1995-07-01

The Chemical Structure and Dynamics program was organized as a major component of Pacific Northwest Laboratory`s Environmental and Molecular Sciences Laboratory (EMSL), a state-of-the-art collaborative facility for studies of chemical structure and dynamics. Our program responds to the need for a fundamental, molecular-level understanding of chemistry at the wide variety of environmentally important interfaces by (1) extending the experimental characterization and theoretical description of chemical reactions to encompass the effects of condensed media and interfaces, and (2) developing a multidisciplinary capability for describing interfacial chemical processes within which the new knowledge generated can be brought to bear on complex phenomena in environmental chemistry and in nuclear waste processing and storage. This research effort was initiated in 1989 and will continue to evolve over the next few years into a program of rigorous studies of fundamental molecular processes in model systems, such as well-characterized surfaces, single-component solutions, clusters, and biological molecules; and studies of complex systems found in the environment (multispecies, multiphase solutions; solid/liquid, liquid/liquid, and gas/surface interfaces; colloidal dispersions; ultrafine aerosols; and functioning biological systems). The success of this program will result in the achievement of a quantitative understanding of chemical reactions at interfaces, and more generally in condensed media, that is comparable to that currently available for gas-phase reactions. This understanding will form the basis for the development of a priori theories for predictions of macroscopic chemical behavior in condensed and heterogeneous media, adding significantly to the value of field-scale environmental models, the prediction of short- and long-term nuclear waste storage stabilities, and other problems related to the primary missions of the DOE.

Chemical Emergencies

Science.gov (United States)

When a hazardous chemical has been released, it may harm people's health. Chemical releases can be unintentional, as in the case of an ... the case of a terrorist attack with a chemical weapon. Some hazardous chemicals have been developed by ...

Quasi-equilibria and plasma chemical similarity in non-isothermal reactive plasmas

International Nuclear Information System (INIS)

Miethke, F.; Rutscher, A.; Wagner, H.E.

2000-01-01

With regard to the output of stable products the mode of operation of non-isothermal plasma chemical reactors shows physical and chemical well defined states, which represent limiting cases and may be interpreted as quasi-equilibrium states. The occurrence and the characteristics of these states, meanwhile more than once observed and described, are demonstrated by an instructive model reaction. Within the frame of the so-called Macroscopic Kinetics a central parameter is dominating the reactor operation. This result may be generalized and is linked up to the application of similarity principles for the reactor operation. After the general formulation of such principles, starting from the balance equations of particles and energy, a dimensionless similarity parameter is formulated, characterizing the composition of the effluent gas of the reactor. The applicability of this parameter is demonstrated by experimental examples. (Authors)

Decontamination of chemical agents from drinking water infrastructure: a literature review and summary.

Science.gov (United States)

Szabo, Jeff; Minamyer, Scott

2014-11-01

This report summarizes the current state of knowledge on the persistence of chemical contamination on drinking water infrastructure (such as pipes) along with information on decontamination should persistence occur. Decontamination options for drinking water infrastructure have been explored for some chemical contaminants, but important data gaps remain. In general, data on chemical persistence on drinking water infrastructure is available for inorganics such as arsenic and mercury, as well as select organics such as petroleum products, pesticides and rodenticides. Data specific to chemical warfare agents and pharmaceuticals was not found and data on toxins is scant. Future research suggestions focus on expanding the available chemical persistence data to other common drinking water infrastructure materials. Decontaminating agents that successfully removed persistent contamination from one infrastructure material should be used in further studies. Methods for sampling or extracting chemical agents from water infrastructure surfaces are needed. Published by Elsevier Ltd.

Advances in unconventional computing

CERN Document Server

2017-01-01

The unconventional computing is a niche for interdisciplinary science, cross-bred of computer science, physics, mathematics, chemistry, electronic engineering, biology, material science and nanotechnology. The aims of this book are to uncover and exploit principles and mechanisms of information processing in and functional properties of physical, chemical and living systems to develop efficient algorithms, design optimal architectures and manufacture working prototypes of future and emergent computing devices. This first volume presents theoretical foundations of the future and emergent computing paradigms and architectures. The topics covered are computability, (non-)universality and complexity of computation; physics of computation, analog and quantum computing; reversible and asynchronous devices; cellular automata and other mathematical machines; P-systems and cellular computing; infinity and spatial computation; chemical and reservoir computing. The book is the encyclopedia, the first ever complete autho...

Chemical and physical quality examination: Chapter 4

Science.gov (United States)

Lamar, William

1953-01-01

In a balanced study of water pollution or water utilization a thorough chemical and physical examination is essential. This provides a basis for evaluation of stream conditions, their effects and remedies. Such information is of value to the general public who are interested in clean water and in recreation, hunting, fishing, and wildlife; to the chemist, engineer, hydrologist, and industrialist who are interested in the domestic and industrial use of water both as raw material and as a vehicle for the removal of waste materials; to the sanitarian who is interested in healthful conditions; and to the biologist who is interested in maintaining a favorable biological balance. For every living plant and animal there are optimum physical and chemical conditions and these characteristics are determining factors in the aquatic life of any body of water.

Novel Miniature Spectrometer For Remote Chemical Detection

International Nuclear Information System (INIS)

Pipino, Andrew C.R.

2000-01-01

New chemical sensing technologies are critically important for addressing many of EM's priority needs as discussed in detail at http://emsp.em.doe.gov/needs. Many technology needs were addressed by this research. For example, improved detection strategies are needed for non-aqueous phase liquids (NAPL's), such as PCE (Cl2C=CCl2) and TCE (HClC=CCl2), which persist in the environment due their highly stable structures. By developing a miniature, ultra-sensitive, selective, and field-deployable detector for NAPL's, the approximate source location could be determined with minimal investigative expense. Contaminant plumes could also be characterized in detail. The miniature spectrometer developed under Project No.60231 could also permit accurate rate measurements in less time, either in the field or the laboratory, which are critically important in the development, testing, and ultimate utilization of models for describing contaminant transport. The technology could also be used for long-term groundwater monitoring or long-term stewardship in general. Many science needs are also addressed by the Project 60231, since the effort significantly advances the measurement science of chemical detection. Developed under Project No.60231, evanescent wave cavity ring-down spectroscopy (EW-CRDS) is a novel form of CRDS, which is an the emerging optical absorption technique. Several review articles on CRDS, which has been generally applied only to gas-phase diagnostics, have been published1-3. EW-CRDS4-10 forms the basis for a new class of chemical sensors that extends CRDS to other states of matter and leads to a miniaturized version of the concept. EW-CRDS uses miniature solid-state optical resonators that incorporate one or more total internal reflection (TIR) surfaces, which create evanescent waves. The evanescent waves emanate from the TIR surfaces, sampling the surrounding medium. The utility of evanescent waves in chemical analysis forms the basis for the field of attenuated

Chemical sensors for nuclear industry

International Nuclear Information System (INIS)

Gnanasekaran, K.I.

2012-01-01

Development of chemical sensors for detection of gases at trace levels for applications in nuclear industry will be highlighted. The sensors have to be highly sensitive, reliable and rugged with long term stability to operate in harsh industrial environment. Semiconductor and solid electrolyte based electrochemical sensors satisfy the requirements. Physico-chemical aspects underlying the development of H 2 sensors in sodium and in cover gas circuit of the Fast breeder reactors for its smooth functioning, NH 3 and H 2 S sensors for use in Heavy water production industries and NO x sensors for spent fuel reprocessing plants will be presented. Development of oxygen sensors to monitor the oxygen level in the reactor containments and sodium sensors for detection of sodium leakages will also be discussed. The talk will focus the general aspects of identification of the sensing material for the respective analyte species, development of suitable chemical route for preparing them as fine powders, the need for configuring them in thick film or thin film geometries and their performance. Pulsed laser deposition method, an elegant technique to prepare the high quality thin films of multicomponent oxides is demonstrated for preparation of nanostructured thin films of complex oxides and its use in tailoring the morphology of the complex sensing material in the desired form by optimizing the in-situ growth conditions. (author)

New chemical-DSMC method in numerical simulation of axisymmetric rarefied reactive flow

Science.gov (United States)

Zakeri, Ramin; Kamali Moghadam, Ramin; Mani, Mahmoud

2017-04-01

The modified quantum kinetic (MQK) chemical reaction model introduced by Zakeri et al. is developed for applicable cases in axisymmetric reactive rarefied gas flows using the direct simulation Monte Carlo (DSMC) method. Although, the MQK chemical model uses some modifications in the quantum kinetic (QK) method, it also employs the general soft sphere collision model and Stockmayer potential function to properly select the collision pairs in the DSMC algorithm and capture both the attraction and repulsion intermolecular forces in rarefied gas flows. For assessment of the presented model in the simulation of more complex and applicable reacting flows, first, the air dissociation is studied in a single cell for equilibrium and non-equilibrium conditions. The MQK results agree well with the analytical and experimental data and they accurately predict the characteristics of the rarefied flowfield with chemical reaction. To investigate accuracy of the MQK chemical model in the simulation of the axisymmetric flow, air dissociation is also assessed in an axial hypersonic flow around two geometries, the sphere as a benchmark case and the blunt body (STS-2) as an applicable test case. The computed results including the transient, rotational and vibrational temperatures, species concentration in the stagnation line, and also the heat flux and pressure coefficient on the surface are compared with those of the other chemical methods like the QK and total collision energy (TCE) models and available analytical and experimental data. Generally, the MQK chemical model properly simulates the chemical reactions and predicts flowfield characteristics more accurate rather than the typical QK model. Although in some cases, results of the MQK approaches match with those of the TCE method, the main point is that the MQK does not need any experimental data or unrealistic assumption of specular boundary condition as used in the TCE method. Another advantage of the MQK model is the

Chemical Space of DNA-Encoded Libraries.

Science.gov (United States)

Franzini, Raphael M; Randolph, Cassie

2016-07-28

In recent years, DNA-encoded chemical libraries (DECLs) have attracted considerable attention as a potential discovery tool in drug development. Screening encoded libraries may offer advantages over conventional hit discovery approaches and has the potential to complement such methods in pharmaceutical research. As a result of the increased application of encoded libraries in drug discovery, a growing number of hit compounds are emerging in scientific literature. In this review we evaluate reported encoded library-derived structures and identify general trends of these compounds in relation to library design parameters. We in particular emphasize the combinatorial nature of these libraries. Generally, the reported molecules demonstrate the ability of this technology to afford hits suitable for further lead development, and on the basis of them, we derive guidelines for DECL design.

40 CFR 63.103 - General compliance, reporting, and recordkeeping provisions.

Science.gov (United States)

2010-07-01

... Chemical Manufacturing Industry § 63.103 General compliance, reporting, and recordkeeping provisions. (a... during periods when the primary control device is out of service), records must be kept of whether the... both the Administrator and the owner or operator of a source, reports may be submitted on electronic...

Effects of toxic chemicals on the reproductive system. Council on Scientific Affairs.

Science.gov (United States)

1985-06-21

In an effort to make physicians more aware of the hazards of the workplace to pregnant workers, the Council on Scientific Affairs' Advisory Panel on Reproductive Hazards in the Workplace prepared this third and final report reviewing the effects of chemical exposure. A total of 120 chemicals were considered for reviews based on an estimation of their imminent hazard, ie, widespread use and/or inherent toxicity. Following a brief introduction, which sets out general principles, clinical applications, and aids to the recognition of a human teratogen, the report presents reviews and opinions for three representative chemicals. Information concerning the remaining 117 compounds is available upon request.

Constraining the QCD phase diagram by tricritical lines at imaginary chemical potential

CERN Document Server

de Forcrand, Philippe

2010-01-01

We present unambiguous evidence from lattice simulations of QCD with three degenerate quark species for two tricritical points in the (T,m) phase diagram at fixed imaginary \\mu/T=i\\pi/3 mod 2\\pi/3, one in the light and one in the heavy mass regime. These represent the boundaries of the chiral and deconfinement critical lines continued to imaginary chemical potential, respectively. It is demonstrated that the shape of the deconfinement critical line for real chemical potentials is dictated by tricritical scaling and implies the weakening of the deconfinement transition with real chemical potential. The generalization to non-degenerate and light quark masses is discussed.

Near miss reporting in the chemical process industry: an overview

NARCIS (Netherlands)

Schaaf, van der T.W.

1995-01-01

The research programme described in this paper focuses on the human component of system failure in general, and more specifically on the design and implementation of information systems for registration and analysis of so called near misses (or: near accidents) in the chemical process industry. Its

A numerical study of three-dimensional droplets spreading on chemically patterned surfaces

KAUST Repository

Zhong, Hua; Wang, Xiao-Ping; Sun, Shuyu

2016-01-01

We study numerically the three-dimensional droplets spreading on physically flat chemically patterned surfaces with periodic squares separated by channels. Our model consists of the Navier-Stokes-Cahn-Hilliard equations with the generalized Navier

PHYSICAL AND CHEMICAL CHARACTERIZATION OF NEUROLOGICAL INJURY IN AN AVIAN MODEL OF PRIMARY GENERALIZED EPILEPSY

Directory of Open Access Journals (Sweden)

Edward Kendall

2011-05-01

Full Text Available Purpose This study was undertaken to determine if the epileptic chicken phenotype exhibited unique physical and chemical neurological changes. Methods Quantitative 1H-MRI/MRS measurements were performed on adult control (Rr and epileptic (rr chickens. The metrics included nuclear relaxation rate, diffusion rate and concentration of metabolites associated with neuronal cells. Comparisons were performed using Students t or Mann-Whitney tests according to the data distribution. Results Proton density measurements detected no significant difference in density among the cerebral hemispheres and optic lobes within the control and epi birds, nor between bird phenotypes. Thus, within experimental error it appears that brain tissue density is similar in adult control and epi birds. Volume calculation from images spanning the entire brain confirmed that a consistent feature of the epi genotype was megalencephaly. Nuclear relaxation (T2 values obtained for the control bird were within the normal variant range for neuronal tissue. However, T2's of the epi birds were significantly higher than that of the controls ((158 ms versus 123 ms. Similarly, in the diffusion data there was no apparent hemispheric bias. The optic lobes of the control animals exhibited an apparent diffusion coefficient significantly lower than that found for the cerebrum (Table 2. Interestingly, this differential was not apparent in the epi birds. The control birds across all regions of interest exhibited an ADC significantly less than that of the epi birds. Quantitative 1Hspectroscopy using tissue extracts collected immediately after sacrifice revealed phenotypic differences in lactate, glutamate, creatine and NAA but not GABA. A reduction in NAA was detected in the cerebrum of epi birds. This is in agreement with the generally held view that seizure activity causes loss of neurones, thus the loss of N-acetyl aspartate. HPLC data corroborated the spectroscopic NAA findings but also

Radiation-chemical yields of molecular hydrogen formation in cyclohexane based alcohols

International Nuclear Information System (INIS)

Val'ter, A.I.; Kovalev, G.V.

1988-01-01

Molecular hydrogen radiation-chemical yields in γ-irradiated cyclohexanol, 1.2-cis- and 1.2-trans-cyclohexandiols and inositol are determined within the general problem frameworks of radiolysis mechanism for cyclohexanering-base alcohols. Irradiation was conducted at 77 and 293 K, dose rate - 4 Gy/s. Hydrogen concentration in all irradiated alcohols depends linearly on the dose. Radiation-chemical yields of H 2 and of stabilized radicals, as well, in the irradiated crystalline alcohols are analyzed depending on the irradiation temperature, alcohol molecular structure

An integrated multi-label classifier with chemical-chemical interactions for prediction of chemical toxicity effects.

Science.gov (United States)

Liu, Tao; Chen, Lei; Pan, Xiaoyong

2018-05-31

Chemical toxicity effect is one of the major reasons for declining candidate drugs. Detecting the toxicity effects of all chemicals can accelerate the procedures of drug discovery. However, it is time-consuming and expensive to identify the toxicity effects of a given chemical through traditional experiments. Designing quick, reliable and non-animal-involved computational methods is an alternative way. In this study, a novel integrated multi-label classifier was proposed. First, based on five types of chemical-chemical interactions retrieved from STITCH, each of which is derived from one aspect of chemicals, five individual classifiers were built. Then, several integrated classifiers were built by integrating some or all individual classifiers. By testing the integrated classifiers on a dataset with chemicals and their toxicity effects in Accelrys Toxicity database and non-toxic chemicals with their performance evaluated by jackknife test, an optimal integrated classifier was selected as the proposed classifier, which provided quite high prediction accuracies and wide applications. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Selecting the Best: Evolutionary Engineering of Chemical Production in Microbes

DEFF Research Database (Denmark)

Shepelin, Denis; Hansen, Anne Sofie Lærke; Lennen, Rebecca

2018-01-01

, we focus primarily on a more challenging problem-the use of evolutionary engineering for improving the production of chemicals in microbes directly. We describe recent developments in evolutionary engineering strategies, in general, and discuss, in detail, case studies where production of a chemical......Microbial cell factories have proven to be an economical means of production for many bulk, specialty, and fine chemical products. However, we still lack both a holistic understanding of organism physiology and the ability to predictively tune enzyme activities in vivo, thus slowing down rational...... engineering of industrially relevant strains. An alternative concept to rational engineering is to use evolution as the driving force to select for desired changes, an approach often described as evolutionary engineering. In evolutionary engineering, in vivo selections for a desired phenotype are combined...

Solution-chemical route to generalized synthesis of metal germanate nanowires with room-temperature, light-driven hydrogenation activity of CO2 into renewable hydrocarbon fuels.

Science.gov (United States)

Liu, Qi; Zhou, Yong; Tu, Wenguang; Yan, Shicheng; Zou, Zhigang

2014-01-06

A facile solution-chemical route was developed for the generalized preparation of a family of highly uniform metal germanate nanowires on a large scale. This route is based on the use of hydrazine monohydrate/H2O as a mixed solvent under solvothermal conditions. Hydrazine has multiple effects on the generation of the nanowires: as an alkali solvent, a coordination agent, and crystal anisotropic growth director. Different-percentage cobalt-doped Cd2Ge2O6 nanowires were also successfully obtained through the addition of Co(OAc)2·4H2O to the initial reaction mixture for future investigation of the magnetic properties of these nanowires. The considerably negative conduction band level of the Cd2Ge2O6 nanowire offers a high driving force for photogenerated electron transfer to CO2 under UV-vis illumination, which facilitates CO2 photocatalytic reduction to a renewable hydrocarbon fuel in the presence of water vapor at room temperature.

Assessing the chemical contamination dynamics in a mixed land use stream system

DEFF Research Database (Denmark)

Sonne, Anne Thobo; McKnight, Ursula S.; Rønde, Vinni

2017-01-01

Traditionally, the monitoring of streams for chemical and ecological status has been limited to surface water concentrations, where the dominant focus has been on general water quality and the risk for eutrophication. Mixed land use stream systems, comprising urban areas and agricultural production......, are challenging to assess with multiple chemical stressors impacting stream corridors. New approaches are urgently needed for identifying relevant sources, pathways and potential impacts for implementation of suitable source management and remedial measures. We developed a method for risk assessing chemical...... stressors in these systems and applied the approach to a 16-km groundwater-fed stream corridor (Grindsted, Denmark). Three methods were combined: (i) in-stream contaminant mass discharge for source quantification, (ii) Toxic Units and (iii) environmental standards. An evaluation of the chemical quality...

Chemical profiling of chemical warfare agents for forensic purposes

NARCIS (Netherlands)

Noort, D.; Reuver, L.P.J. de; Fidder, A.; Tromp, M.; Verschraagen, M.

2010-01-01

A program has been initiated towards the chemical profiling of chemical warfare agents, in order to support forensic investigations towards synthesis routes, production sites and suspect chemical suppliers. Within the first stage of the project various chemical warfare agents (VX, sulfur mustard,

Carcinogenic and mutagenic properties of chemicals in drinking water

Energy Technology Data Exchange (ETDEWEB)

Bull, R J

1985-12-01

Isolated cases of careless handling of industrial and domestic waste has lead to a wide variety of dangerous chemicals being inadvertently introduced into drinking water. However, chemicals with established carcinogenic and mutagenic properties that occur with a high frequency and in multiple locations are limited in number. To date, the chief offenders have been chemicals of relatively low carcinogenic potency. Some of the more common chemicals are formed as by-products of disinfection. The latter process is generally regarded as essential to the production of a ''microbiologically safe'' drinking water. Consequently, any reductions in what may be a relatively small carcinogenic risk must be balanced against a potential for a higher frequency of waterborne infectious disease. The results of recent toxicological investigations will be reviewed to place the potential carcinogenic and mutagenic hazards frequently associated with drinking water into perspective. First, evidence for the carcinogenicity of certain volatile organic compounds such as trichloroethylene, tetrachloroethylene and carbon tetrachloride is considered. Second, the carcinogenic activity that can be ascribed to various by-products of chlorination is reviewed in some detail. Finally, recent evidence that other chemicals derived from the treatment and distribution of drinking water is highlighted as an area requiring move systematic attention. 72 references.

Jefferson Davis and the Failure of Confederate Military Strategy, 1861-1865

Science.gov (United States)

2010-04-14

seventeen. Here he first met some of the men who later held key roles in the Confederate Army: Albert Sidney Johnston, Leonidas Polk, and later Robert...General Lee’s magnificent Army ofNorthem Virginia. Throughout the war Jefferson Davis failed to assign to any theater and entirely subsidiary role ...fight. 24 0 ENDNOTES 1 A. H. McDannald, B.L., ed., The Modern Concise Encyclopedia, vol. III, (New York: Unicorn Press, 1941), 490-491. 2 Harry

Mixed waste chemical compatibility: A testing program for plastic packaging components

International Nuclear Information System (INIS)

Nigrey, P.J.

1995-01-01

The purpose of hazardous and radioactive materials packaging is to enable these materials to be transported without posing a threat to the health or property of the general public. To achieve this aim, regulations in the United States have been written establishing general design requirements for such packagings. While no regulations have been written specifically for mixed waste packaging, regulations for the constituents of mixed wastes, i.e., hazardous and radioactive substances, have been codified by the US Department of Transportation (DOT, 49 CFR 173) and the US Nuclear Regulatory Commission (NRC, 10 CFR 71). The design requirements for both hazardous [49 CFR 173.24 (e)(1)] and radioactive [49 CFR 173.412 (g)] materials packaging specify packaging compatibility, i.e., that the materials of the packaging at sign d any contents be chemically compatible with each other. Furthermore, Type A [49 CFR 173.412 (g)] and Type B (10 CFR 71.43) packaging design requirements stipulate that there be no significant chemical, galvanic, or other reaction between the materials and contents of the package. Based on these requirements, a Chemical Compatibility Testing Program was developed in the Transportation Systems Department at Sandia National Laboratories (SNL). The program attempts to assure any regulatory body that the issue of packaging material compatibility towards hazardous and radioactive materials has been addressed. This program has been described in considerable detail in an internal SNL document, the Chemical Compatibility Test Plan ampersand Procedure Report (Nigrey 1993)

High-Performance Liquid Chromatography in the Undergraduate Chemical Engineering Laboratory

Science.gov (United States)

Frey, Douglas D.; Guo, Hui; Karnik, Nikhila

2013-01-01

This article describes the assembly of a simple, low-cost, high-performance liquid chromatography (HPLC) system and its use in the undergraduate chemical engineering laboratory course to perform simple experiments. By interpreting the results from these experiments students are able to gain significant experience in the general method of…

A Coupled Chemical and Mass Transport Model for Concrete Durability

DEFF Research Database (Denmark)

Jensen, Mads Mønster; Johannesson, Björn; Geiker, Mette Rica

2012-01-01

In this paper a general continuum theory is used to evaluate the service life of cement based materials, in terms of mass transport processes and chemical degradation of the solid matrix. The model established is a reactive mass transport model, based on an extended version of the Poisson-Nernst-...

Identification of Chemical Toxicity Using Ontology Information of Chemicals

Directory of Open Access Journals (Sweden)

Zhanpeng Jiang

2015-01-01

Full Text Available With the advance of the combinatorial chemistry, a large number of synthetic compounds have surged. However, we have limited knowledge about them. On the other hand, the speed of designing new drugs is very slow. One of the key causes is the unacceptable toxicities of chemicals. If one can correctly identify the toxicity of chemicals, the unsuitable chemicals can be discarded in early stage, thereby accelerating the study of new drugs and reducing the R&D costs. In this study, a new prediction method was built for identification of chemical toxicities, which was based on ontology information of chemicals. By comparing to a previous method, our method is quite effective. We hope that the proposed method may give new insights to study chemical toxicity and other attributes of chemicals.

Generally applicable limits on intakes of uranium based on its chemical toxicity and the radiological significance of intakes at those limits

International Nuclear Information System (INIS)

Thorne, M C; Wilson, J

2015-01-01

Uranium is chemically toxic and radioactive, and both considerations have to be taken into account when limiting intakes of the element, in the context of both occupational and public exposures. Herein, the most recent information available on the chemical toxicity and biokinetics of uranium is used to propose new standards for limiting intakes of the element. The approach adopted allows coherent standards to be set for ingestion and inhalation of different chemical forms of the element by various age groups. It also allows coherent standards to be set for occupational and public exposures (including exposures of different age groups) and for various exposure regimes (including short-term and chronic exposures). The proposed standards are more restrictive than those used previously, but are less restrictive than the Minimal Risk Levels proposed recently by the US Agency for Toxic Substances and Disease Registry. Having developed a set of proposed limits based solely on chemical toxicity considerations, the radiological implications of exposure at those proposed limits are investigated for natural, depleted and enriched uranium. (paper)

Instructions for the Tier I Emergency and Hazardous Chemical Inventory Form

Science.gov (United States)

The purpose of the Emergency Planning and Community Right-to-Know Act Tier I form is to provide State and local officials and the public with information on the general chemical hazard types and locations at your facility, if above reporting thresholds.

User needs in chemical information

International Nuclear Information System (INIS)

Lehmann, H.; Poetzscher, G.; Wilson, A.J.C.

1990-05-01

Information has become an absolutely indispensable factor in the modern industrial society. In chemistry, detailed information about all compounds known is required. Learned journals, research and conference reports, publications from universities and learned societies, and dissertations present the progress in research. It is important that all properties of compounds (stereochemistry, physical values, chemical and environmental behaviour, toxicity etc.) reported in these publications be indexed and made available to the users. There is also a need for factual and/or numerical data and reviews concerning general or specific topics. High on the list of desiderata are timeliness, accuracy and completeness of the information. Abstracting and indexing services and database producers have to take in consideration that a high degree of userfriendliness is necessary. In the future, most of the information will be offered in computer readable form (factual and numerical databases, reaction databases, information on CD-ROM etc.), a fact which will require many improvements in the flow of information in order to render possible an easy and direct access to the chemical information worldwide. (author). 15 refs

User needs in chemical information

Energy Technology Data Exchange (ETDEWEB)

Lehmann, H; Poetzscher, G [FIZ Chemie GmbH, Berlin (Germany); Wilson, A J.C. [Cambridge Univ., Cambridge (United Kingdom). Crystallographic Data Centre

1990-05-01

Information has become an absolutely indispensable factor in the modern industrial society. In chemistry, detailed information about all compounds known is required. Learned journals, research and conference reports, publications from universities and learned societies, and dissertations present the progress in research. It is important that all properties of compounds (stereochemistry, physical values, chemical and environmental behaviour, toxicity etc.) reported in these publications be indexed and made available to the users. There is also a need for factual and/or numerical data and reviews concerning general or specific topics. High on the list of desiderata are timeliness, accuracy and completeness of the information. Abstracting and indexing services and database producers have to take in consideration that a high degree of userfriendliness is necessary. In the future, most of the information will be offered in computer readable form (factual and numerical databases, reaction databases, information on CD-ROM etc.), a fact which will require many improvements in the flow of information in order to render possible an easy and direct access to the chemical information worldwide. (author). 15 refs.

Decomposition theory of chemical reactions

International Nuclear Information System (INIS)

Rabitz, S.; Rabitz, H.

1977-01-01

The coupled channel formulation is utilized to variationally derive approximate closed-form expressions for reactive transition matrices. In conjunction with this effort it is shown that the effect of differing choices of possible channel coupling arrays becomes important when incomplete channel basis sets are used. Generalized techniques are employed to derive the necessary variational principles. The inherent coupling of the Green's functions in the resulting expression for the transition matrix makes inclusion of continuum states in the basis sets less crucial. The practical viability of this formulation as a computational scheme for chemical systems is discussed

Mapping student thinking in chemical synthesis

Science.gov (United States)

Weinrich, Melissa

In order to support the development of learning progressions about central ideas and practices in different disciplines, we need detailed analyses of the implicit assumptions and reasoning strategies that guide students' thinking at different educational levels. In the particular case of chemistry, understanding how new chemical substances are produced (chemical synthesis) is of critical importance. Thus, we have used a qualitative research approach based on individual interviews with first semester general chemistry students (n = 16), second semester organic chemistry students (n = 15), advanced undergraduates (n = 9), first year graduate students (n = 15), and PhD candidates (n = 16) to better characterize diverse students' underlying cognitive elements (conceptual modes and modes of reasoning) when thinking about chemical synthesis. Our results reveal a great variability in the cognitive resources and strategies used by students with different levels of training in the discipline to make decisions, particularly at intermediate levels of expertise. The specific nature of the task had a strong influence on the conceptual sophistication and mode of reasoning that students exhibited. Nevertheless, our data analysis has allowed us to identify common modes of reasoning and assumptions that seem to guide students' thinking at different educational levels. Our results should facilitate the development of learning progressions that help improve chemistry instruction, curriculum, and assessment.

The application of nuclear energy to the Canadian chemical process industry

International Nuclear Information System (INIS)

Robertson, R.F.S.

1976-03-01

A study has been made to determine what role nuclear energy, either electrical or thermal, could play in the Canadian chemical process industry. The study was restricted to current-scale CANDU type power reactors. It is concluded that the scale of operation of the chemical industry is rarely large enough to use blocks of electrical power (e) of 500 MW or thermal power (t) of 1500 MW. Thus, with a few predictable exceptions, the role of nuclear energy in the Canadian chemical industry will be as a general thermal/electrical utility supplier, serving a variety of customers in a particular geographic area. This picture would change if nuclear steam generators of 20 to 50 MW(t) become available and are economically competitive. (author)

The chemical structure of the insoluble organic matter from carbonaceous meteorites

Science.gov (United States)

Derenne, S.; Robert, F.

2008-09-01

Carbonaceous chondrites are the most primitive objects of the solar system. They contain substantial amounts of carbon (up to 3%), mostly occurring in macromolecular insoluble organic matter (IOM). This IOM is generally considered as a record of interstellar synthesis and may contain precursors of prebiotic molecules possibly deposited on earth by meteoritic bombardments. For these reasons, chondritic IOM has been raising interest for long and it is therefore of special interest to decipher its chemical structure. It is now well established that the chemical structure of this macromolecular material is based on aromatic moieties linked by short aliphatic chains and comprising substantial amounts of heteroatoms. However, its precise chemical structure could only be recently specified. The aim of this presentation is to propose a molecular model for the chemical structure of IOM isolated from non-metamorphosed carbonaceous chondrites. This model is derived from a large set of data obtained through a combination of techniques including various spectrocopies, high resolution transmission electron microscopy (HRTEM) and chemical and thermal degradations. Cosmochemical implications of such a structure will also be discussed.

Gut microbiota in toxicological risk assessment of drugs and chemicals: The need of hour.

Science.gov (United States)

Velmurugan, Ganesan

2018-03-06

The advent of industrial revolution caused a large inflow of synthetic chemicals for medical, agricultural, industrial and other purposes in the world. In general, these chemicals were subjected to toxicological risk assessment for human health and ecology before release for public use. But today we are witnessing a negative impact of some of these chemicals on human health and environment indicating an underestimation of toxic effects by current risk assessment protocol. Recent studies established gut microbiota as one of the key player in intercession of toxicity of drugs and synthetic chemicals. Hence, the need of the hour is to include the assessment for microbiota specifically gut microbiota in human toxicological risk assessment protocol. Herewith we are proposing a framework for assessment of gut microbiota upon exposure to drugs or chemicals.

From Chemical Forces to Chemical Rates: A Historical/Philosophical Foundation for the Teaching of Chemical Equilibrium

Science.gov (United States)

Quilez, Juan

2009-01-01

With this paper, our main aim is to contribute to the realisation of the chemical reactivity concept, tracing the historical evolution of the concept of chemical affinity that eventually supported the concept of chemical equilibrium. We will concentrate on searching for the theoretical grounds of three key chemical equilibrium ideas: "incomplete…

Nikolai Frederik Severin Grundtvig

DEFF Research Database (Denmark)

Heggem, Synnøve Sakura

2005-01-01

This is an article on N.F.S: Grundtvig in one of the worlds most known standard works on religion, Eliades "Encyclopedia of Religion"(2. ed), 2005......This is an article on N.F.S: Grundtvig in one of the worlds most known standard works on religion, Eliades "Encyclopedia of Religion"(2. ed), 2005...

Tech Notebook: E-Reference Tools.

Science.gov (United States)

Sassman, Charlotte

1999-01-01

Two resources to help students conduct research are the new CD-ROM versions of the Encarta Encyclopedia Deluxe 2000 (for strong readers, grades 5-8) and the Year 2000 Grolier Multimedia Encyclopedia (for strong readers, grades 3 and up). By supplementing traditional text-based information with specialized features (e.g., virtual tours and video…

Mapping of Drug-like Chemical Universe with Reduced Complexity Molecular Frameworks.

Science.gov (United States)

Kontijevskis, Aleksejs

2017-04-24

The emergence of the DNA-encoded chemical libraries (DEL) field in the past decade has attracted the attention of the pharmaceutical industry as a powerful mechanism for the discovery of novel drug-like hits for various biological targets. Nuevolution Chemetics technology enables DNA-encoded synthesis of billions of chemically diverse drug-like small molecule compounds, and the efficient screening and optimization of these, facilitating effective identification of drug candidates at an unprecedented speed and scale. Although many approaches have been developed by the cheminformatics community for the analysis and visualization of drug-like chemical space, most of them are restricted to the analysis of a maximum of a few millions of compounds and cannot handle collections of 10 8 -10 12 compounds typical for DELs. To address this big chemical data challenge, we developed the Reduced Complexity Molecular Frameworks (RCMF) methodology as an abstract and very general way of representing chemical structures. By further introducing RCMF descriptors, we constructed a global framework map of drug-like chemical space and demonstrated how chemical space occupied by multi-million-member drug-like Chemetics DNA-encoded libraries and virtual combinatorial libraries with >10 12 members could be analyzed and mapped without a need for library enumeration. We further validate the approach by performing RCMF-based searches in a drug-like chemical universe and mapping Chemetics library selection outputs for LSD1 targets on a global framework chemical space map.

Nonequilibrium thermodynamics transport and rate processes in physical, chemical and biological systems

CERN Document Server

Demirel, Yasar

2014-01-01

Natural phenomena consist of simultaneously occurring transport processes and chemical reactions. These processes may interact with each other and may lead to self-organized structures, fluctuations, instabilities, and evolutionary systems. Nonequilibrium Thermodynamics, 3rd edition emphasizes the unifying role of thermodynamics in analyzing the natural phenomena. This third edition updates and expands on the first and second editions by focusing on the general balance equations for coupled processes of physical, chemical, and biological systems. The new edition contains a new chapte

Interaction between diffusion and chemical stresses

International Nuclear Information System (INIS)

Yang Fuqian

2005-01-01

The present work studies the interaction between chemical stresses and diffusion. A new relation between hydrostatic stress and concentration of solute atoms is established. For a solid free of action of body force, the Laplacian of the hydrostatic stress is proportional to the Laplacian of the concentration of solute atoms, that is, deviation of the hydrostatic stress from its local average is proportional to deviation of the local concentration of solute atoms. A general relationship among surface concentration of solute atoms, normal stress and surface deformation of a solid is then derived, in which the normal stress is dependent on the mean curvature of the undeformed surface and tangential components of the surface displacement. A closed-form solution of the steady state concentration of solute atoms in a thin plate is obtained. It turns out that linear distribution of solute atoms in the plate is non-existent due to the interaction between chemical stresses and diffusion

The chemical safety of irradiated foods

International Nuclear Information System (INIS)

Giddings, G.G.

1990-01-01

While animal feeding studies and other biological testing methods have contributed greatly to the establishment of the toxicological safety of irradiated foods, probably no other single factor has lent itself so conclusively to this end as the availability of an unprecedented volume of analytical chemistry data on radiolytic products generated in a variety of foods and their raw materials and ingredients, collected at laboratories worldwide over decades. Such direct analytical chemical evidence, backed up by a general knowledge of radiation chemistry of bio-organic materials has allowed regulatory scientists and other competent, qualified and objective interested parties to discern with a high degree of confidence what takes place chemically at the sub-molecular level, and in the parts-per-trillion range, as a result of food irradiation. Ironically, this has also opened the way for nonqualified, subjectively negatively biased individuals to, for example, grossly misrepresent such compounds as benzene and formaldehyde in this context in an alarmist fashion to anyone predisposed to listen

Safety criteria for nuclear chemical plants

International Nuclear Information System (INIS)

Ball, P.W.; Curtis, L.M.

1983-01-01

Safety measures have always been required to limit the hazards due to accidental release of radioactive substances from nuclear power plants and chemical plants. The risk associated with the discharge of radioactive substances during normal operation has also to be kept acceptably low. BNFL (British Nuclear Fuels Ltd.) are developing risk criteria as targets for safe plant design and operation. The numerical values derived are compared with these criteria to see if plants are 'acceptably safe'. However, the criteria are not mandatory and may be exceeded if this can be justified. The risk assessments are subject to independent review and audit. The Nuclear Installations Inspectorate also has to pass the plants as safe. The assessment principles it uses are stated. The development of risk criteria for a multiplant site (nuclear chemical plants tend to be sited with many others which are related functionally) is discussed. This covers individual members of the general public, societal risks, risks to the workforce and external hazards. (U.K.)

Chemical sensors based on surface charge transfer

Science.gov (United States)

Mohtasebi, Amirmasoud; Kruse, Peter

2018-02-01

The focus of this review is an introduction to chemiresistive chemical sensors. The general concept of chemical sensors is briefly introduced, followed by different architectures of chemiresistive sensors and relevant materials. For several of the most common systems, the fabrication of the active materials used in such sensors and their properties are discussed. Furthermore, the sensing mechanism, advantages, and limitations of each group of chemiresistive sensors are briefly elaborated. Compared to electrochemical sensors, chemiresistive sensors have the key advantage of a simpler geometry, eliminating the need for a reference electrode. The performance of bulk chemiresistors can be improved upon by using freestanding ultra-thin films (nanomaterials) or field effect geometries. Both of those concepts have also been combined in a gateless geometry, where charge transport though a percolation network of nanomaterials is modulated via adsorbate doping.

Physico-chemical properties of water in bentonite

International Nuclear Information System (INIS)

Torikai, Yuji; Sato, Seichi; Ohashi, Hiroshi

1994-01-01

As a part of safety analysis on ground layer disposal, in order to estimate nuclides migration behavior from engineering shielding materials, it is required to modelize migration process of nuclides in bentonite and chemical species relating to corrosion, to estimate solubility and to specify application condition of geochemical calculation code. In this study, as a part of elucidation of nuclide migration process, physico-chemical properties of water in bentonite and montmorillonite using steam pressure method were determined. As a result, following items were found: (1) Even if 1/3 of water in bentonite is near free water, it is far from a region dealable with dilute solution in the electrolyte solution theory. And, (2) the water in bentonite has generally small activity in comparison with dilute solution, then has smaller solubility than estimation value of calculation code. (G.K.)

Non-allergic cutaneous reactions in airborne chemical sensitivity--a population based study.

Science.gov (United States)

Berg, Nikolaj Drimer; Linneberg, Allan; Thyssen, Jacob Pontoppidan; Dirksen, Asger; Elberling, Jesper

2011-06-01

Multiple chemical sensitivity (MCS) is characterised by adverse effects due to exposure to low levels of chemical substances. The aetiology is unknown, but chemical related respiratory symptoms have been found associated with positive patch test. The purpose of this study was to investigate the relationship between cutaneous reactions from patch testing and self-reported severity of chemical sensitivity to common airborne chemicals. A total of 3460 individuals participating in a general health examination, Health 2006, were patch tested with allergens from the European standard series and screened for chemical sensitivity with a standardised questionnaire dividing the participants into four severity groups of chemical sensitivity. Both allergic and non-allergic cutaneous reactions--defined as irritative, follicular, or doubtful allergic reactions--were analysed in relationship with severity of chemical sensitivity. Associations were controlled for the possible confounding effects of sex, age, asthma, eczema, atopic dermatitis, psychological and social factors, and smoking habits. In unadjusted analyses we found associations between allergic and non-allergic cutaneous reactions on patch testing and the two most severe groups of self-reported sensitivity to airborne chemicals. When adjusting for confounding, associations were weakened, and only non-allergic cutaneous reactions were significantly associated with individuals most severely affected by inhalation of airborne chemicals (odds ratio = 2.5, p = 0.006). Our results suggest that individuals with self-reported chemical sensitivity show increased non-allergic cutaneous reactions based on day 2 readings of patch tests. Copyright © 2011 Elsevier GmbH. All rights reserved.

Household Chemical Emergencies

Science.gov (United States)

... Content Home Be Informed Household Chemical Emergencies Household Chemical Emergencies Although the risk of a chemical accident ... reduce the risk of injury. Before a Household Chemical Emergency It is critical to store household chemicals ...

Development of a Mechanical Analysis System Considering Chemical Transitions of Barrier Materials

International Nuclear Information System (INIS)

Sahara, F.; Murakami, T.; Ito, H.; Kobayashi, I.; Yokozeki, K.

2006-01-01

An analysis system for the long-term mechanical behavior of barrier materials (MACBECE: Mechanical Analysis system considering Chemical transitions of Bentonite-based and Cement-based materials) was developed in order to improve the reliability of the evaluation of the hydraulic field that is one of the important environmental conditions in the safety assessment of the TRU waste disposal in Japan. The MACBECE is a system that calculates the deformation of barrier materials using their chemical property changes as inputs, and subsequently their hydraulic conductivity taking both their chemical property changes and deformation into consideration. This paper provides a general description of MACBECE and the results of experimental analysis carried out using MACBECE. (authors)

The overlapping distribution method to compute chemical potentials of chain molecules

NARCIS (Netherlands)

Mooij, G.C.A.M.; Frenkel, D.

1994-01-01

The chemical potential of continuously deformable chain molecules can be estimated by measuring the average Rosenbluth weight associated with the virtual insertion of a molecule. We show how to generalize the overlapping-distribution method of Bennett to histograms of Rosenbluth weights. In this way

Hazardous chemical and radioactive wastes at Hanford

International Nuclear Information System (INIS)

Keller, J.F.; Stewart, T.L.

1991-07-01

The Hanford Site was established in 1944 to produce plutonium for defense. During the past four decades, a number of reactors, processing facilities, and waste management facilities have been built at Hanford for plutonium production. Generally, Hanford's 100 Area was dedicated to reactor operation; the 200 Area to fuel reprocessing, plutonium recovery, and waste management; and the 300 Area to fuel fabrication and research and development. Wastes generated from these operations included highly radioactive liquid wastes, which were discharged to single- and double-shell tanks; solid wastes, including both transuranic (TRU) and low-level wastes, which were buried or discharged to caissons; and waste water containing low- to intermediate-level radioactivity, which was discharged to the soil column via near-surface liquid disposal units such as cribs, ponds, and retention basins. Virtually all of the wastes contained hazardous chemical as well as radioactive constituents. This paper will focus on the hazardous chemical components of the radioactive mixed waste generated by plutonium production at Hanford. The processes, chemicals used, methods of disposition, fate in the environment, and actions being taken to clean up this legacy are described by location

Hazardous chemical and radioactive wastes at Hanford

International Nuclear Information System (INIS)

Keller, J.F.; Stewart, T.L.

1993-01-01

The Hanford Site was established in 1944 to produce plutonium for defense. During the past four decades, a number of reactors, processing facilities, and waste management facilities were built at Hanford for plutonium production. Generally, Hanford's 100 Area was dedicated to reactor operation; the 200 Areas to fuel reprocessing, plutonium recovery, and waste management; and the 300 Area to fuel fabrication and research and development. Wastes generated from these operations included highly radioactive liquid wastes, which were discharged to single- and double-shell tanks; solid wastes, including both transuranic and low-level wastes, which were buried or discharged to caissons; and waste water containing low- to intermediate-level radioactivity, which was discharged to the soil column via near-surface liquid disposal units such as cribs, ponds, and retention basins. Virtually all of the wastes contained hazardous chemicals as well as radioactive constituents. This paper focuses on the hazardous chemical components of the radioactive mixed waste generated by plutonium production at Hanford. The processes, chemicals used, methods of disposition, fate in the environment, and actions being taken to clean up this legacy are described by location

Fatty acid-derived biofuels and chemicals production in Saccharomyces cerevisiae

Directory of Open Access Journals (Sweden)

Yongjin J. Zhou

2014-09-01

Full Text Available Volatile energy costs and environmental concerns have spurred interest in the development of alternative, renewable, sustainable and cost-effective energy resources. Advanced biofuels have potential to replace fossil fuels in supporting high-power demanding machinery such as aircrafts and trucks. Microbial biosynthesis is generally considered as an environmental friendly refinery process, and fatty acid biosynthesis is an attractive route to synthesize chemicals and especially drop-in biofuels due to the high degree of reduction of fatty acids. The robustness and excellent accessibility to molecular genetics make the yeast S. cerevisiae a suitable host for the production of biofuels, chemicals and pharmaceuticals, and recent advances in metabolic engineering as well as systems and synthetic biology allow us to engineer the yeast fatty acid metabolism and modification pathways for production of advanced biofuels and chemicals.

Military Psychology. Volume 9, Number 4, 1997. Effects of Chemical Protective Clothing on Military Performance

Science.gov (United States)

1997-01-01

Hoarding or stealing chemical protective Rationalization (finding reasons not to train in equipment chemical protective clothing) Hypochondriasis ...overreactions involves development of bodily com- plaints, that is, somatization , which result in dramatic increases in reports for sick call or visits to the...doctor (The Adjutant General, 1979; Weisaeth, 1993). This hypochondriasis occurs as people focus attention on their bodies and internal sensations

General Aspects and First Progress Report on a Frame of a Research on Specific Professional Knowledge of Chemistry Teachers Associated with the Notion of Chemical Nomenclature

Directory of Open Access Journals (Sweden)

Gerardo Andrés Perafán Echeverri

2014-04-01

Full Text Available Within the framework of research about professional teacher’s knowledge, our business is to identify and to characterize with case study method, a kind of specific professional teacher´s knowledge of Chemistry professorate, associated to the chemical nomenclature notion. This kind of research guides the sight to the teaching contents, but it postulates the teacher as an essential actor of that knowledge, rather than ignore of the other actors (didactic community, researchers, specialists, students, etc. our research realizes the specific construction that the teacher makes, beyond the «spontaneous epistemologies» category, between others, which seems to deny an academic and discipline character of the built knowledge by the teachers. First, we show a brief reference to the research program on professional teacher´s knowledge which frames in the development of research line about Specific Professional Teacher´s Knowledge associated with Particular Categories, which belongs to the research group «Por las Aulas Colombianas- INVAUCOL». After that, we show a short justification about the choice of the particular category: chemical nomenclature, as a studied object, besides the historical importance that it has to the professional teaching consolidation, recognizing the teacher´s specific contributions to discipline body construction of school knowledge. Finally, weset in consideration some general methodological criteria defined in this research, and we show too, some preliminary reflections derived from field work in thepresent state of the project.

Chemical engineering and thermodynamics using Mat lab

International Nuclear Information System (INIS)

Kim Heon; Kim, Moon Gap; Lee, Hak Yeong; Yeo, Yeong Gu; Ham, Seong Won

2002-02-01

This book consists of twelve chapters and four appendixes about chemical engineering and thermodynamics using Mat lab, which deals with introduction, energy budget, entropy, thermodynamics process, generalization on any fluid, engineering equation of state for PVT properties, deviation of the function, phase equilibrium of pure fluid, basic of multicomponent, phase equilibrium of compound by state equation, activity model and reaction system. The appendixes is about summary of computer program, related mathematical formula and material property of pure component.

Explosive and chemical threat detection by surface-enhanced Raman scattering: A review

DEFF Research Database (Denmark)

Hakonen, Aron; Andersson, Per Ola; Schmidt, Michael Stenbæk

2015-01-01

Acts of terror and warfare threats are challenging tasks for defense agencies around the world and of growing importance to security conscious policy makers and the general public. Explosives and chemical warfare agents are two of the major concerns in this context, as illustrated by the recent...... progressively better, smaller and cheaper, and can today be acquired for a retail price close to 10,000 US$. This contribution aims to give a comprehensive overview of SERS as a technique for detection of explosives and chemical threats. We discuss the prospects of SERS becoming a major tool for convenient in......-situ threat identification and we summarize existing SERS detection methods and substrates with particular focus on ultra-sensitive real-time detection. General concepts, detection capabilities and perspectives are discussed in order to guide potential users of the technique for homeland security and anti-warfare...

chemical safety and chemical security overview

African Journals Online (AJOL)

IICBA01

Wafaa M. Abdou. Chemical Industries Division, National Research Centre, ... substances to attain an acceptably low risk of exposure. Security is: ... Sharing locations of chemicals can publicize targets for theft .... D. Personal Protective Equipments (PPE): ... E. Lighting & Noise Levels ... PPE. ➢ Autoclave or sterilize wastes.