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THE CRYSTAL STRUCTURE OF A MICROLITE-GROUP MINERAL WITH A FORMULA NEAR NaCaTa(2)O(6)F FROM THE MORRO REDONDO MINE, CORONEL MURTA, MINAS GERAIS, BRAZIL

ANDRADE, Marcelo B.; Atencio, Daniel; MENEZES FILHO, Luiz A. D.; ELLENA, Javier
Fonte: MINERALOGICAL ASSOC CANADA Publicador: MINERALOGICAL ASSOC CANADA
Tipo: Artigo de Revista Científica
ENG
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We present electron-microprobe and single-crystal X-ray-diffraction data for a microlite-group mineral with a formula near NaCaTa(2)O(6)F from the Morro Redondo mine, Coronel Murta, Minas Gerais, Brazil. On the basis of these data, the formula is A(Na(0.88)Ca(0.88)Pb(0.02)square(0.22))(Sigma 2.00) (B)(Ta(1.70)Nb(0.14)Si(0.12)As(0.04))(Sigma 2.00) (X)[(O(5.75)(OH)(0.25)](Sigma 6.00) (Y)(F(0.73)square(0.27))(Sigma 1.00). According to the new nomenclature for the pyrochlore-supergroup minerals, it is intermediate between fluornatromicrolite and "" fluorcalciomicrolite"". The crystal structure, F (d3) over barm, a = 10.4396(12) angstrom, has been refined to an R(1) value of 0.0258 (wR(2) = 0.0715) for 107 reflections (MoK alpha radiation). There is a scarcity of crystal-chemical data for pyrochlore-supergroup minerals in the literature. A compilation of these data is presented here.; FAPESP (Fundacao de Amparo a Pesquisa do Estado de Sao Paulo)[2008/04984-7]; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); FAPESP (Fundacao de Amparo a Pesquisa do Estado de Sao Paulo)[2009/09125-5]

Um professor de Química e dois contextos escolares: o conhecimento pedagógico do conteúdo em ação; A chemistry teacher and two scholar contexts: the pedagogical content knowledge in action

Silva, Aroldo Nascimento
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 21/09/2012 PT
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Este estudo se enquadra na área de formação de professores e mostra como um professor de Ensino Médio inserido em contextos escolares distintos realiza o ensino de química, tendo em vista os diferentes personagens envolvidos em um ambiente de mediação pedagógica - professor, estudantes e instituição escolar - e como isso modifica a sua forma de ensinar. Para compreender como o seu conhecimento base é utilizado ao ensinar um determinado tópico de química em instituições escolares distintas, utilizou-se como referencial teórico o conhecimento pedagógico do conteúdo (PCK), que possibilita entender como o conteúdo específico pode ser pedagogicamente modificado de modo a torná-lo um conhecimento acessível ao estudante, levando em conta os condicionantes do contexto educativo. Nossos dados compreendem registro em áudio e vídeo de aulas do professor investigado em duas escolas distintas, referentes ao mesmo conteúdo químico, entrevistas semiestruturadas, reflexões vídeo-estimuladas e observação participante. O acesso ao PCK foi realizado por meio do instrumento CoRe (Representação do Conteúdo) e da ferramenta de análise das interações discursivas. Esta última possibilitou entender os significados que surgem em um ambiente de mediação pedagógica...

An extended IUPAC nomenclature code for polymorphic nucleic acids

Johnson, Andrew D.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica
EN
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The International Union of Pure and Applied Chemistry (IUPAC) code specified nearly 25 years ago provides a nomenclature for incompletely specified nucleic acids. However, no system currently exists that allows for the informatics representation of the relative abundance at polymorphic nucleic acids (e.g. single nucleotide polymorphisms) in a single specified character, or a string of characters. Here, I propose such an information code as a natural extension to the IUPAC nomenclature code, and present some potential uses and limitations to such a code. The primary anticipated use of this extended nomenclature code is to assist in the representation of the rapidly growing space of information in human genetic variation.

Análise de nomes da química orgânica à luz da teoria do léxico gerativo - da análise sintático-semântica à geração das estruturas químicas através dos combinadores de Parser

Dias, Márcio de Souza
Fonte: Universidade Federal de Uberlândia Publicador: Universidade Federal de Uberlândia
Tipo: Dissertação
POR
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O presente trabalho propõe um sistema automático de análise de nomes de compostos da Química Orgânica visando a geração do desenho de suas estruturas químicas. Para tanto, o sistema recebe um nome de um composto orgânico, analisa-o sintática e semanticamente e, caso ele represente um composto quimicamente correto, gera uma saída visual para a estrutura química que lhe corresponda. Um avanço que o sistema apresenta com relação a outros que se propõem a efetuar tarefa semelhante e o fato de ele conseguir analisar tanto nomes de compostos que se enquadram nos padrões das nomenclaturas oficiais vigentes, quanto aqueles que, apesar de não se enquadrarem nos mesmos, representam compostos orgânicos verdadeiros (quando ocorrer tal situação, o sistema teria resolvido um problema de ambigüidade de nomenclatura). As análises sintática e semântica são guiadas pelos tipos dos componentes dos nomes químicos, fato que motivou a implementação do sistema nos moldes do formalismo da Teoria do Léxico Gerativo (TLG). Além disso, as análises guiadas pelo tipo motivaram a escolha dos combinadores de Parser e da Linguagem de Programação Funcional Clean como utilitários eficazes e adequados na execução das análises lingüísticas. O sistema implementado representa uma ferramenta muito útil como instrutor automático de Química Orgânica. ______________________________________________________________________________ ABSTRACT; This work proposes an automatic system of analysis for Organic Chemistry compound names aiming to generate pictures of chemical structures. In order to accomplish this...

Establishment, value assignment, and characterization of new WHO reference reagents for six molecular forms of human chorionic gonadotropin

Bristow, A.; Berger, P.; Bidart, J.M.; Birken, S.; Norman, R.; Stenman, U.H.; Sturgeon, C.
Fonte: Amer Assoc Clinical Chemistry Publicador: Amer Assoc Clinical Chemistry
Tipo: Artigo de Revista Científica
Publicado em //2005 EN
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Background: The International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) established a Working Group to investigate means of improving the comparability of immunoassays for human chorionic gonadotropin (hCG), which was selected as a prototype glycoprotein analyte. The Working Group identified development of unambiguous nomenclature and production of new highly purified International Reference Reagents calibrated in substance concentrations as its primary objectives. Methods: Preparations of intact hCG, nicked hCG, hCG ß-subunit, nicked hCG ß-subunit, hCG -subunit, and hCG ß-core fragment were purified from a crude urinary hCG preparation, ampouled, lyophilized, and assigned values in substance concentrations (mol/L). Value assignment and accelerated degradation studies were carried out in accordance with WHO protocols for International Reference Reagents. Results: The ampouled standards were assigned final values based on the recovery of immunoreactive material after reconstitution. The degradation studies showed that the standards were highly stable. Conclusions: The nomenclature of hCG-related molecules and immunoassays has been adopted by the IFCC, and the standards prepared and characterized by the Working Group have been formally adopted by the WHO as the First International Reference Reagents for six hCG-related molecules. These developments will enable better understanding of what assays for hCG measure and should ultimately help to improve the clinical application of these assays.; Adrian Bristow...

Formulación química inorgánica en educación secundaria (Póquer de química)

Esteve Castell, José Joaquín
Fonte: Escuela Cardenal Cisneros. Centro Adscrito a la UAH Publicador: Escuela Cardenal Cisneros. Centro Adscrito a la UAH
Tipo: Artigo de Revista Científica Formato: application/pdf
SPA
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Uno de los principales problemas al que se enfrenta, en general, el profesorado de Ciencias Experimentales (en su labor de transmisor de conceptos) es la especificidad y dificultad que tiene, para el alumnado, la nomenclatura y epistemología utilizadas en las distintas áreas que conforman la Ciencia. Es a raíz de este problema práctico que planteamos la siguiente propuesta metodológica para la enseñanza de la Formulación Química Inorgánica en segundo ciclo de la E.S.O. En ella proponemos al alumnado que, con un juego de cartas, con su implicación directa y con un ambiente de aula abierto al intercambio de planteamientos y opiniones pueda construir su propio aprendizaje, en colaboración con sus compañeros/as y el profesorado.; One of the main problems Science teachers must face while transmitting concepts is that Science nomenclature and epistemology is too specifi c and difficult for students. Starting from this practical problem we introduce the following methodological proposal to teach chemical formulae for inorganic compounds in the second cycle of the Secondary Education (E.S.O.). We aim at making our students build their own learning with the help of classmates and teachers. To do that, we use a card game which increases students’ involvement in the task and improves classroom atmosphere by offering students opportunities for exchanging approaches and/or opinions.

Sulfosalt systematics: a review. Report of the sulfosalt sub-committee of the IMA Commission on Ore Mineralogy

Moelo, Y.; Makovicky, E.; Mozgova, N.; Jambor, J.; Cook, N.; Pring, A.; Paar, W.; Nickel, E.; Graeser, S.; Karup-Moller, S.; Balic-Zunic, T.; Mumme, W.; Vurro, F.; Topa, D.; Bindi, L.; Bente, K.; Shimizu, M.
Fonte: E. Schweizerbart’sche Verlagsbuchhandlung Publicador: E. Schweizerbart’sche Verlagsbuchhandlung
Tipo: Artigo de Revista Científica
Publicado em //2008 EN
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This report deals with a general reexamination of the systematics of sulfosalts. It represents an update of the activity of the Sulfosalt Sub-Committee within the Commission on Ore Mineralogy of the International Mineralogical Association, in connection with the Commission on New Minerals, Nomenclature and Classification (CNMNC-IMA). Part I presents generalities of sulfosalt definition and nomenclature. After an extended chemical definition of sulfosalts, attention is focused on "classic" sulfosalts with As3+, Sb3+, Bi3+ or Te4+ as cations, corresponding to the general formula (Me+, Me'2+, etc.)x [(Bi, Sb, As)3+,Te4+]y [(S, Se, Te)2–]z (Me, Me': various metals). General aspects of their chemistry and classification principles are summarized, especially with regard to chemical substitutions and modular analysis of complex crystal structures. On this basis, Part II presents a review of sulfosalt systematics. Six main crystal-chemical sub-groups are distinguished (plus some unclassified species), concerning more than 220 valid mineral species. Among others whose status is questioned are those considered to be varieties of well-defined species; minerals with ill-defined X-ray data; those that are possibly identical species; and those that represent the potential revalidation of old species. More than 50 crystal structures still remain unsolved...

Identification of the difficulties in teaching and learning of introductory organic chemistry in Ireland and the development of a second-level intervention programme to address these

O'Dwyer, Anne
Fonte: University of Limerick Publicador: University of Limerick
Tipo: info:eu-repo/semantics/doctoralThesis; all_ul_research; ul_published_reviewed; ul_theses_dissertations
ENG
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peer-reviewed; This project involved the effective implementation of Chemistry Education Research (CER) into classroom practice. The project was carried out in two cycles. Cycle One of the project involved two investigations: one at second-level and one at third-level. Cycle Two involved the development, implementation and evaluation of an intervention in the Irish second-level schools programme to address the issues identified in Cycle One. The difficulties of organic chemistry have been investigated and researched in many other countries. However, there has been no explicit research carried out investigating the difficulties experienced by novices learning organic chemistry in Ireland. This Action Research project involved an investigation of the difficulties experienced by those learning organic chemistry at second-level and at introductory third-level in Ireland. The second-level study involved the completion of questionnaires by chemistry teachers in 73 Second-Level schools and pupils in 35 second-level schools teaching Leaving Certificate Chemistry in Ireland. At third-level, questionnaires were completed by lecturers in 12 different third-level Irish institutions and to students in three different Institutions. These questionnaires provided an insight into the teaching and learning of organic chemistry. It was found that those teaching and learning organic chemistry at second-level and third-level experience many common topics as difficult: IUPAC nomenclature; functional groups; characteristics of organic compounds; reaction types; reaction mechanisms and practical work. Organic chemistry accounts for a substantial amount of the Leaving Certificate Chemistry syllabus (20%) and examination (25%). Using the findings from Cycle One and those from CER...

Vicente Seabra Telles e a criação da nomenclatura em português para a Química 'Nova' de Lavoisier

Luna,Fernando J.
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2013 PT
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In 1787, Lavoisier and coworkers published a 314-page book entitled Méthode de nomenclature chimique in which a novel system for the naming of compounds and elements was presented. The Brazilian chemist Vicente Coelho de Seabra Telles (1764-1804) was responsible for translating it into Portuguese. Telles proposed the adoption not only of the Latin etymology, but decided to use Latin suffixes as well, because of the similarity between Latin and the Portuguese language. In doing so, he made the names of the compounds in Portuguese bear a closer resemblance to the names in Latin than to those in French or Spanish.

Análisis de la evolución de las concepciones de la ndc a través de secuencias didácticas centradas en aspectos sociológicos de la nomenclatura de compuestos químicos inorgánicos

Guzmán Prada, Yasunari
Fonte: Ibagué : Universidad del Tolima, 2015; Facultad de Ciencias de la Educación, Programa de Maestría en Educación Publicador: Ibagué : Universidad del Tolima, 2015; Facultad de Ciencias de la Educación, Programa de Maestría en Educación
Tipo: Trabajo de grado - Maestría; Text; info:eu-repo/semantics/masterThesis; info:eu-repo/semantics/publishedVersion Formato: application/pdf
SPA
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146 Páginas; Recurso Electrónico; La presente investigación tiene como objeto de estudio determinar la evolución de las concepciones sobre Naturaleza de la Ciencia “NdC” que tienen los estudiantes de educación media colombiana a través de secuencias didácticas centrada en aspectos sociológicos de la Nomenclatura de Compuestos Químicos Inorgánicos “NCQI”. El problema de investigación se sustenta desde la perspectiva teórica de la naturaleza de ciencia y las concepciones metadisciplinares que los estudiantes tienen sobre ésta. Se plantea un estudio de carácter educativo, bajo un enfoque cualitativo-hermenéutico. En el análisis de contenido se identificó el sentido explícito de las ideas de los estudiantes acerca de la Nomenclatura de Compuestos Químicos Inorgánicos “NCQI” y la incidencia de estos compuestos en el medio ambiente. El proceso de investigación estuvo regido por un sistema categorial que orientó el proceso, el cual se encuentra en el marco de los consensos de naturaleza de ciencia (Aduriz, 2001). En los resultados y las conclusiones se presentan las concepciones que tienen los estudiantes sobre NdC desde el componente sociológico de la NCQI a partir de la incidencia de la aplicación de las secuencias didácticas en la evolución conceptual.; ABSTRACT. This research study aims to determine the evolution of the conceptions of Nature of Science "NdC" with the Colombian high school students through didactic sequences focused on sociological aspects of the Nomenclature of Inorganic Chemistry "NCQI". The research problem is based from the theoretical perspective of the nature of science and metadisciplinares conceptions that students have on it. A study of educational...

Implementación de herramientas TIC como una estrategia para el aprendizaje significativo de la química

Martínez Hernández, Mercedelma; Acevedo Pedraza Olga Lucía
Fonte: Ibagué : Universidad del Tolima, 2014; Facultad de Ciencias de la Educación, Maestría en Educación Publicador: Ibagué : Universidad del Tolima, 2014; Facultad de Ciencias de la Educación, Maestría en Educación
Tipo: Trabajo de grado - Maestría; Text; info:eu-repo/semantics/masterThesis; info:eu-repo/semantics/submittedVersion Formato: application/pdf
SPA
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101 Páginas; Recurso Electrónico; El ser humano constantemente está adquiriendo conocimientos que con el paso del tiempo toman forma y dan lugar a nuevos interrogantes que lo llevarán a un futuro conocimiento, así pasa su vida tratando de explicar su existencia y los fenómenos que ocurren a su alrededor. Es así como la preocupación del hombre desde que nace hasta que muere es su educación y su formación integral; recibe las primeras pautas en la familia, las consolida en la escuela y finalmente las practica en la sociedad. Por lo anterior y como docentes comprometidas con una educación que despierte el interés, el deseo por aprender y aplicar el conocimiento a la solución de problemas del mundo de la vida, nace este trabajo de investigación, el cual tiene por objeto determinar el efecto de la implementación de las Tecnologías de la Información y las Comunicaciones (TIC) en el desarrollo de aprendizajes significativos de química en estudiantes del grado décimo del Instituto Valle del Rio de Oro del municipio de Piedecuesta Santander. El trabajo consiste en la articulación de las clases de química con tecnología en la unidad didáctica “Nomenclatura química”, para lo cual se presentan guías que incluyen estrategias potencialmente facilitadoras del aprendizaje significativo y prácticas de laboratorio en cada uno de los ejes temáticos que permiten a los estudiantes relacionar la química con la vida cotidiana y así encontrarle gusto y sentido a lo que se aprende. Para ello se apoya el trabajo en el uso de herramientas atractivas para los jóvenes como el Facebook...

Recursos per treballar a l’aula la formulació i nomenclatura de química inorgànica

Hernández Santadaría, José Ángel
Fonte: Universidade Autônoma de Barcelona Publicador: Universidade Autônoma de Barcelona
Tipo: Artigo de Revista Científica Formato: application/pdf
Publicado em //2015 CAT
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L’article presenta diversos recursos i activitats elaborats per l’autor que permeten treballar la formulació i nomenclatura de química inorgànica a les classes de química d’educació secundària i de batxillerat, seguint les darreres recomanacions de la IUPAC de l’any 2005.; This article sets forth several resources and activities designed by the author which allow the inclusion of formula writing and nomenclature of inorganic chemistry in the chemistry lessons of compulsory secondary education and Baccalaureate, following the latest IUPAC recommendations in 2005.

Extraction of chemical structures and reactions from the literature

Lowe, Daniel Mark
Fonte: University of Cambridge; Department of Chemistry; Pembroke College Publicador: University of Cambridge; Department of Chemistry; Pembroke College
Tipo: Thesis; doctoral; PhD
EN
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The ever increasing quantity of chemical literature necessitates the creation of automated techniques for extracting relevant information. This work focuses on two aspects: the conversion of chemical names to computer readable structure representations and the extraction of chemical reactions from text. Chemical names are a common way of communicating chemical structure information. OPSIN (Open Parser for Systematic IUPAC Nomenclature), an open source, freely available algorithm for converting chemical names to structures was developed. OPSIN employs a regular grammar to direct tokenisation and parsing leading to the generation of an XML parse tree. Nomenclature operations are applied successively to the tree with many requiring the manipulation of an in-memory connection table representation of the structure under construction. Areas of nomenclature supported are described with attention being drawn to difficulties that may be encountered in name to structure conversion. Results on sets of generated names and names extracted from patents are presented. On generated names, recall of between 96.2% and 99.0% was achieved with a lower bound of 97.9% on precision with all results either being comparable or superior to the tested commercial solutions. On the patent names OPSIN s recall was 2-10% higher than the tested solutions when the patent names were processed as found in the patents. The uses of OPSIN as a web service and as a tool for identifying chemical names in text are shown to demonstrate the direct utility of this algorithm. A software system for extracting chemical reactions from the text of chemical patents was developed. The system relies on the output of ChemicalTagger...

Organic chemistry: methane to macromolecules

Roberts, John D.; Stewart, Ross; Caserio, Marjorie C.
Fonte: W. A. Benjamin, Inc. Publicador: W. A. Benjamin, Inc.
Tipo: Book; NonPeerReviewed Formato: application/pdf
Publicado em //1971
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The success achieved by this book's forerunners, Basic Principles of Organic Chemistry and Modern Organic Chemistry, was to a considerable extent due to the rigor with which the subject of organic chemistry was presented. In the present work we have tried to paint an interesting, relevant, and up-to-date picture of organic chemistry while retaining the rigorous approach of the earlier books. Organic chemistry sometimes appears to be enormously complex to the beginning student, particularly if he must immediately grapple with the subjects of structural isomerism and nomenclature. We have attempted to avoid this difficulty in the following way. Chapter 1 briefly relates carbon to its neighbors in the Periodic Table and reviews some fundamental concepts. Chapter 2 deals with the four C1 and C2 hydrocarbons-methane, ethane, ethene, and ethyne-and discusses their conformational and configurational properties and some of their chemical reactions. The reader thus makes an acquaintance with the properties of some important organic compounds before dealing in an open-ended way with families of compounds-alkanes, alcohols, etc. A heavy emphasis on spectroscopy is retained but the subject is introduced somewhat later than in the earlier books. Important additions are chapters dealing with enzymic processes and metabolism and with cyclization reactions. Many of the exercises of the earlier books have been retained and have been supplemented with drill-type problems. It seems a shame to burden the mind of the beginning student with trivial names...

Basic Principles of Organic Chemistry, second edition

Roberts, John D.; Caserio, Marjorie C.
Fonte: W. A. Benjamin, Inc. Publicador: W. A. Benjamin, Inc.
Tipo: Book; NonPeerReviewed Formato: application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf;
Publicado em 15/05/1977
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PREFACE: No period in the history of organic chemistry has been as dynamic and productive of research accomplishment as the twelve years between the completion of the first and present editions of this textbook. New reagents, new reactions, and extraordinary syntheses have been manifold. New techniques and new instruments for analysis and determination of structures, improved methods for theoretical calculations, as well as new junctures with physical, inorganic, and biochemistry, have made organic chemistry an enormously vital discipline. But along with this "best of times," there is a "worst of times" coming from the recognition that many widely used organic compounds are more toxic than previously suspected. Some are carcinogenic; some may be destroying the ozone layer in the upper atmosphere, which protects all life from the sun's strong ultraviolet radiation; others are concentrated and persist in living tissue to as yet unknown effect. Nonetheless, our society has come to depend on synthetic organic chemicals, and we may ponder the fact that in just a few years the petroleum that makes so many useful organic compounds easily available will be in very short supply throughout the world. It has been a real challenge for us to try to cover the elements of modern organic chemistry with sufficient breadth to anticipate the interests and needs of the future chemists...

ChEBI – an Open-access Chemistry Resource for the Life Sciences: Facilities for On-line Submission and Curation

Marcus Ennis; Nico Adams; Adriano Dekker; Paula de Matos; Janna Hastings; Kenneth Haug; Duncan Hull; Zara Josephs; Gareth Owen; Steve Turner; Christoph Steinbeck
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Poster
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ChEBI (Chemical Entities of Biological Interest) is a database of ‘small’ molecular entities structured around a chemical ontology. It contains almost 600,000 entries, of which approximately 20,000 have been manually curated, as well as entries for groups (parts of molecular entities) and classes of entities. It provides a wide range of information such as chemical nomenclature, structures and related chemical values, and establishes interrelationships between entities in the ontology, in terms of both structure and role. ChEBI places a strong focus on quality, with exceptional efforts being applied to upholding IUPAC nomenclature recommendations and best IUPAC practices when drawing chemical structures. To invite the community to participate more directly in the future growth and development of ChEBI, we have developed a web-based software utility to enable direct user submissions. Users are encouraged to carry out as much of their own manual curation as possible, e.g. by adding multiple synonyms and database cross-references, and by creating multiple relationships within the ontology. The submissions are automatically validated for uniqueness (both of name and chemical structure) and correctness (such as checking that no non-allowed cycles have inadvertently been created in the ontology graph structure...

ChEBI, an Open-access Chemistry Resource for the Life Sciences: Facilities for On-line Submission and Curation

Marcus Ennis
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Conferência ou Objeto de Conferência
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ChEBI (Chemical Entities of Biological Interest) is a database of ‘small’ molecular entities structured around a chemical ontology. It contains almost 600,000 entries, of which approximately 20,000 have been manually curated, as well as entries for groups (parts of molecular entities) and classes of entities. It provides a wide range of information such as chemical nomenclature, structures and related chemical values, and establishes interrelationships between entities in the ontology, in terms of both structure and role. ChEBI places a strong focus on quality, with exceptional efforts being applied to upholding IUPAC nomenclature recommendations and best IUPAC practices when drawing chemical structures. To invite the community to participate more directly in the future growth and development of ChEBI, we have developed a web-based software utility to enable direct user submissions. Users are encouraged to carry out as much of their own manual curation as possible, e.g. by adding multiple synonyms and database cross-references, and by creating multiple relationships within the ontology. The submissions are automatically validated for uniqueness (both of name and chemical structure) and correctness (such as checking that no non-allowed cycles have inadvertently been created in the ontology graph structure...

Nomenclatura em Química; Nomenclature in Chemistry

Ricardo B. de Alencastro; Universidade Federal do Rio de Janeiro; Roberto de B. Faria; Universidade Federal do Rio de Janeiro
Fonte: Revista Virtual de Química Publicador: Revista Virtual de Química
Tipo: ; Formato: binary/octet-stream
Publicado em 06/04/2011 PT
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O espírito desta Seção é o de informar, mas também o de provocar. Não temos, até hoje, uma Nomenclatura da Química oficial em português, e nada mais natural que iniciemos, neste Ano Internacional da Química (2011), esta discussão. DOI: 10.5935/1984-6835.20110007; The aim of this Section is to inform, but also to provoke. We have, today, an official nomenclature of chemistry in portuguese, and it was only natural that we start in this International Year of Chemistry (2011), this thread. DOI: 10.5935/1984-6835.20110007

Sobre a Nomenclatura de Carboidratos; About the Nomenclature of Carbohydrates

Fabrício Bracht; Universidade Federal do Rio de Janeiro; Ricardo B. de Alencastro; Universidade Federal do Rio de Janeiro
Fonte: Revista Virtual de Química Publicador: Revista Virtual de Química
Tipo: ; Formato: binary/octet-stream
Publicado em 10/11/2011 PT
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Este artigo faz um recorte da história e dos detalhes da nomenclatura de carboidratos. Abordam-se questões relacionadas à evolução histórica da nomenclatura e de sua importância para o que hoje é tomado como referência nos livros de química. Neste texto, são descritos também os protagonistas desta história, com uma breve apresentação de seus trabalhos e de suas contribuições para este tópico. Por fim, algumas recomendações e comentários são feitos sobre as convenções usadas pela IUPAC. DOI: 10.5935/1984-6835.20110039; This article is an excerpt of the history and the details of carbohydrate nomenclature. It addresses issues related to the historical evolution of the nomenclature and their importance to what is now used in reference books in chemistry. In this paper, we report also the protagonists of this story, with a brief presentation of their work and their contributions to this topic. Finally, some recommendations and comments are given about the conventions used by IUPAC. DOI: 10.5935/1984-6835.20110039

The first publication of the New Chemistry in America in Mercurio Peruano (1792) by Joseph Coquette

Bifano,Claudio; Whittembury,Guillermo
Fonte: ASOCIACIÓN INTERCIENCIA Publicador: ASOCIACIÓN INTERCIENCIA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2007 EN
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Joseph Coquette, first director of the non-university scholarly learning center, Lima’s Mining Tribunal in Peru, published (1792) a text on chemistry in the Peruvian journal Mercurio Peruano: "Principles of Physical Chemistry ….", which was the first text published in America on the new chemistry, as it appeared five years before Lavoisier’s book of 1789 was printed in Spanish in Mexico, in 1797. It was complemented by "About the need to perfect and reform the Nomenclature in Chemistry…." in 1793. In addition he published "Didactic dissertation on Mining…..", also in 1792. The present essay examines in extenso "Principles of Physical Chemistry ….", and comments on the others. Some scholars and institutions of advanced learning in the New Continent are also mentioned. Mercurio Peruano is looked upon in more detail, after Alexander von Humboldt deemed it so important that he donated the 12 volume collection to the Berlin Library of King Frederick William III.