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In its attempt to achieve acknowledgement and support as a true science and academic discipline eighteenth-century chemistry experienced that the traditional distinction between theory and practice, respectively between science and art, was an incriminating heritage and did not longer conform to the way chemists saw themselves. In order to substitute the former, socially judging classification into theoretical science and practical art, J. G. Wallerius from Uppsala coined the term pure and applied chemistry in 1751. The idea behind this new conception was that it ought to be chemistry's research aim and not the kind of work, be it manual or intellectual, which was to decide about its branches and their dignity. The change in orientation which took place during the eighteenth century, and which is symbolized by the new dichotomy “pure and applied”, led towards a revaluation of the utilitarian aspects of chemistry. Its historical roots reach back to a long and fruitful cooperation of, and interaction between chemistry and economy, which was reinforced by the Stahlian tradition in Germany and Scandinavia. Subsequently, it was its strong economic bias that helped chemistry to become institutionalized and accepted as an academic discipline distinct from the medico-pharmaceutical profession. The analysis of this change of attitudes, behaviour and institutional pattern suggests that, at least during the period of institutionalization of this particular discipline, social structures and the intrinsic scientific contents are so tightly interrelated, that any division into “internal”, cognitive developments (facts, theory and subject-matter) and “external” conditions (social context and stategies of institutionalization) would be artificial, since they both constitute the scientific community as a context of argumentation and action.  相似文献   
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Ancient mortars played a crucial role in the construction of historical architectures due to their physical and chemical compatibility with traditional building materials such as stones and bricks. Therefore, the analysis and optimization of the ancient mortar formula are significant in the restoration and preservation of historical sites. In this work, 20 mortar samples selected from five ancient stone pagodas in Zhejiang Province, China, were analyzed. The results showed that mud, lime-soil mortar, lime-sand mortar, and lime-gypsum mortar were used as binders in these pagodas. The Ca(OH)2/aggregate ratio ranging from 0.3 to 2.7 was usually used to prepare lime mortar. Protein and polysaccharide were also found in some samples.  相似文献   
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姜萌 《史学月刊》2007,(3):79-85
《陈寅恪的最后二十年》、《顾颉刚和他的弟子们》、《束星北档案》等著作,代表了当前历史传记写作的一种趋势。《陈寅恪的最后二十年》的文本近似历史叙事散文;《顾颉刚和他的弟子们》的文本更接近史学论文;而《束星北档案》则类同电视记录片的文稿。这些著作共有的特点是:在修撰方式上,大量运用了第一手材料;在文本风格上,力求作品深入浅出、雅俗共赏;在写作理念上,坚持真实第一,尊重历史。这一趋势非常值得重视。  相似文献   
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The aim of this paper is to present the publication of the correspondence of Johann Bartholom?us Trommsdorff (1770 bis 1837) and to inform about the history of this project as well as the methodical proceedings and the content of these letters. The opportunities and limitations of the modern Trommsdorff research, based on the publication of his correspondence, will be shown. His contacts have been manifold and expansive. He corresponded with many famous scientists in pharmacy, chemistry, medicine and with important people of intellectual origin. Trommsdorff was a highly important person of the international European relationships in the field of pharmacy. Many publications certify the importance of the Trommsdorff-correspondence. The publication of these letters has opened new biographical aspects and allows to follow the connections and ways of communication in the new age of the foundation of scientific pharmacy.  相似文献   
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This study uses service area–based coverage and various count regression methods to assess neighbourhood-level healthy and unhealthy food environments, and food access associated with different socio-economic groups in Edmonton, Canada. We identify three types of vulnerable neighbourhoods according to different food environments: food deserts (i.e., neighbourhoods lack sufficient access to healthy foods); food swamps (i.e., neighbourhoods have excess access to unhealthy foods); and those with overlaps of food swamps and food deserts. We also identify neighbourhoods with superior access to healthy foods (i.e., food oases). Additionally, our results from regression analyses indicate: (1) child population is negatively associated with both healthy and unhealthy food resources; (2) good access to public transportation is associated with good coverage of all healthy food outlets and convenience stores; and (3) deprived neighbourhoods with higher percentages of minority populations have better coverage of both healthy and unhealthy foods in general. The results from this study can help the City of Edmonton identify the key neighbourhoods with high potential for local business and the hotspot neighbourhoods that require particular support. Tailored strategies are proposed to effectively and efficiently improve food environments with limited resources.  相似文献   
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Abstract

The management of biodiversity represents a research topic that needs to involve not only several (sub-) disciplines from the natural sciences but, in particular, also the social sciences and humanities. Furthermore, over the last couple of years, the need for the integration of other kinds of knowledge (experience based or indigenous knowledge) is increasingly acknowledged. For instance, the incorporation of such knowledge is indispensable for place-based approaches to sustainable land management, which require that the specific ecological and social context is addressed. However, desirable as it may be, such an engagement of the holders of tacit knowledge is not easy to achieve. It demands reconciling well-established scientific procedural standards with the implicit or explicit criteria of relevance that apply in civil society — a process that typically causes severe tensions and comes up against both habitual as well as institutional constraints. The difficulty of managing such tensions is amplified particularly in large integrated projects and represents a major challenge to project management. At the Helmholtz Centre for Environmental Research — UFZ, several integrated research projects have been conducted over the past years in which experience has been gained with these specific challenges. This paper presents some of the lessons learned from large integrated projects, with an emphasis on project design and management structure. At the centre of the present contribution are experiences gained in the coordination and management of LEGATO (LEGATO stands for Land-use intensity and Ecological EnGineering — Assessment Tools for risks and Opportunities in irrigated rice based production systems, see www.legato-project.net), an ongoing, large-scale, inter- and transdisciplinary research project dealing with the management of irrigated rice landscapes in Southeast Asia. In this project, local expertise on traditional production systems is absolutely crucial but needs to be integrated with natural and social science research to identify future-proof land management systems.  相似文献   
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