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1.
Fauque DM 《Ambix》2011,58(2):116-135
Founded in 1919, the International Union of Pure and Applied Chemistry (IUPAC) was successor to the International Association of Chemical Societies (IACS), which had been founded eight years earlier at the initiative of Albin Haller. The statutes of the IUPAC (like those of the IACS) were written in French, and it was agreed that the IUPAC's administrative headquarters should be in Paris. With these arrangements in place, the role of French chemists generally, and of Haller and Charles Moureu in particular, assumed crucial importance. In 1927, on the occasion of the centenary of Marcelin Berthelot's birth, plans were laid for an international centre for chemistry in Paris, soon to be known as the Maison de la Chimie. From the start, the Maison de la Chimie project was led by the French, most conspicuously by Jean Gérard, general secretary of the Société de chimie industrielle and of the IUPAC. Gérard's contribution to a number of national and international committees, notably for scientific documentation, left an enduring legacy. The years between 1918 and 1927, especially 1918-1919, were decisive for the rebuilding, on many fronts, of international networks embracing individuals and institutions recently separated by war. This article examines the particular case of chemistry, with reference to this wider context and to the widely shared determination to fashion an organisation that would transcend national boundaries and embrace both the pure and the applied aspects of the discipline.  相似文献   

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Horrocks S 《Ambix》2011,58(2):150-170
This paper draws on evidence from a range of sources to consider the extent to which World War II served as a turning point in the employment opportunities open to women chemists in Britain. It argues that wartime conditions expanded women's access to some areas of employment, but that these opportunities represented, in many ways, an expansion of existing openings rather than wholly new ones, and not all of them proved permanent. Instead, women chemists benefited more permanently from increased state expenditure on higher education and on research and development after the war. This enabled some women to remain in what had originally been temporary wartime posts and others to secure employment in wholly new positions. Women were most successful in securing positions created by the expansion of state welfare and support for agriculture, but also found new employment opportunities as a result of the heavy investment in weapons development that accelerated with the advent of the Cold War. In higher education, an initial expansion of openings was not sustained, and the proportion of women in university chemistry departments actually fell during the second half of the 1950s. Industry presents a rather ambiguous picture, with many firms continuing to refuse to employ women chemists, whereas elsewhere they enjoyed enhanced opportunities and better salaries than those offered before the war. This did not mean, however, that women chemists received equal treatment to their male colleagues, and, despite the changes, they remained concentrated in subordinate positions and were expected to concentrate on routine work. Prospects in the 1950s were certainly better than they had been during the 1930s, but they remained strongly gendered.  相似文献   

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Congresses, conferences, symposia, consultations, and seminars in the field of chemical sciences held with participation of the russian academy of sciencesVI International Frumkin Symposium Fundamental Aspects of Electrochemistry*  相似文献   

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A dicopper(I) double helicate oxidizes and rapidly reorganises to form a stable pentadentate dicopper(II) double helicate due to the proximity of pendant pyridyl rings as studied by electrochemical and structural analyses.  相似文献   

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For a chemical reaction network, persistence is the property that no species tend to extinction if all species are initially present. We investigate the stronger property of vacuous persistence: the same asymptotic feature with a weaker requirement on initial states, namely that all species be implicitly present. By implicitly present, we mean for instance that if only water is present and the reaction network incorporates the information that water is made of hydrogen and oxygen, then hydrogen and oxygen are implicitly present. Persistence is inherently interesting and has implications for the global asymptotic stability of equilibrium states. Our main tools are the work of A. I. Vol’pert on the nullity and positivity of species concentrations, and the enabling notion of reachability. The main result states that a reaction network is vacuously persistent if and only if the set of all species is the only set of species that both is closed with respect to reachability and causes the implicit presence of all species. This paper is the first in a series of three articles. Two sequel papers introduce additional formalisms and use them to describe two large classes of reaction networks that are used as models in biochemistry and are vacuously persistent.  相似文献   

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Examples of the use of the RSS 1.0 (RDF Site Summary) specification together with CML (Chemical Markup Language) to create a metadata based alerting service termed CMLRSS for molecular content are presented. CMLRSS can be viewed either using generic software or with modular opensource chemical viewers and editors enhanced with CMLRSS modules. We discuss the more automated use of CMLRSS as a component of a World Wide Molecular Matrix of semantically rich chemical information.  相似文献   

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As a consequence of the globalisation of trade and industry and other human activities, reliability of and confidence in measurement results is increasingly required, also in the field of chemical analysis, so that measurements made in one country will be accepted in other countries without the necessity to repeat them. The prerequisite for confidence is comparability on the basis of known uncertainties which in turn are based on traceability to recognised references. Traceability structures for chemical measurements are required which, by providing calibration means traceable to national standards, allow uncertainty statements to be made at field level, thus establishing comparability. Such traceability structures are now being developed in all industrialised countries. To ensure international comparability, mutual recognition of the national activities in metrology in chemistry is required in addition. The Mutual Recognition Agreement (MRA) for national measurement standards and calibration certificates issued by national metrology institutes, which is currently under way within the framework of the Metre Convention, aimes at providing the necessary international confidence for all kinds of measurements. The field of chemical analysis is included in the international metrological infrastructure through the new Consultative Committee for Amount of Substance (CCQM). Carefully selected key comparison measurements, which cover the most important areas where traceability is required, and which are carried out by national metrology institutes in cooperation with other national institutes entrusted with the provision of part of the national references for chemical measurements, form the basis for declarations of equivalence under the MRA. The results of the first key comparisons and studies carried out so far clearly show that the group of laboratories involved in the key comparisons is capable of establishing the international references (key comparison reference values) for chemical measurements with sufficient accuracy, also in complicated matrices.  相似文献   

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The gas-phase reaction of CF3 with HCN has been examined over a wide conversion range using CF3I as a thermal and photolytic source of radicals. Quantitative and qualitative results show a significant increase of the specific rate constant for the hydrogen abstraction reaction relative to CF3 recombination when reaction is carried out under ultraviolet irradiation. This “extra” formation of the reaction product, CF3H, has been assigned to the participation of iodine in this system through the formation of a (I-HCN) intermediate. Arrhenius parameters obtained for the addition mechanism of I to HCN do not seem to conform to a single reaction step, on the contrary, they correspond to a more complex reaction scheme.  相似文献   

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Some general dependences of the injection volumes of reaction components on time have been derived for the feedback controlled chemical reactor. .  相似文献   

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