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Perceptions of food systems and food acquisition decisions are grounded in specific socio‐economic and environmental contexts. Working in two relatively affluent urban communities in Melbourne, Australia and San Diego County, USA, this article explores the ways that individuals perceive their food systems, where they acquire food, and their definitions of ‘local’ sourcing. Surveys and interviews reveal a clear discrepancy between the ideals and the reality of food acquisition decision‐making, particularly the desire to eat ‘local food’. Survey respondents' realities do not live up to their expectations. These practices can largely be explained by the interplay between the respondents' perceived priorities, food preferences, dietary requirements, and decision‐making constraints in particular urban geographies. Further research is needed on the role of perceptions in food decision‐making in specific geographic contexts.  相似文献   
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The transformation of the socialist societies of Central and Eastern Europe has been commonly described as a transition from a planned economy to a market economy and from a (semi)authoritarian system to a liberal democracy. According to this perspective, the implementation of new political and economic institutions was supposed to free the – so far suppressed – nature of all societies to become capitalist democracies. Such a vision of transformation dominated Polish public and academic discourse. It has been challenged by critics, who emphasized that transformation is an ambiguous process taking place at the level of social life rather than a macro-institutional level. Nevertheless, new concepts often reproduced characteristics of the rejected approach – a tendency to build dichotomous models based on simplified images of a pathological socialist legacy on one hand and of desired capitalist order on the other. Only recently a shift in the transformation discourse might be observed. The best examples are studies employing ethnographic methods, which focus on the level of everyday practices, and study how systemic changes were experienced by social actors. The article is an analysis of the social sciences’ discourse on transformation in the context of the broader public discourse in Poland. It depicts the transitology paradigm and its critique evolving from institutional and cultural perspectives. The focus is on concepts of homo sovieticus, ‘winners and losers’, learned helplessness and the like. Finally, the implications of ethnographic approaches are discussed. The case provokes questions about the role of social scientists in the vital processes of their own society.  相似文献   
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This study presents the first reconstruction of the smelting conditions in 16th- to 18th-century smelters from Miedziana Góra (Holy Cross Mountains, Poland). Based on geochemical (inductively coupled plasma mass spectrometry/emission spectrometry, X-ray fluorescence) and mineralogical analysis (X-ray diffractometry, scanning electron microscopy, electron probe micro-analysis) of historical slags, their chemical/phase composition and the basic smelting parameters (temperature, melt viscosity, and oxygen fugacity) were determined. Due to the differences in chemical and phase composition, slags from different smelting stages have been distinguished: hypocrystalline slags (MG6) from speiss/matte production and glassy (MG1–MG5) from matte conversion. In glassy slags, pyroxenes, quartz/cristobalite grains, and aggregates composed of metallic Cu and PbO are dispersed in the glass. Hypocrystalline slags are composed of wollastonites, anorthites, and metallic Cu. The temperature range at which the slags were formed was from ~1100°C (solidus temperature) to 1150–1200°C (liquidus temperature). The silicate melt's viscosity was from log η = 1.19 to 4.42 Pa s (at 1100–1200°C). The higher viscosity of MG1–MG5 slags indicates that, unlike MG6 slags, they were not formed during gravity separation. Information about the phase composition made it possible to determine the oxygen fugacity in the range of log fO2 = −4 to −12 atm. High oxygen fugacity indicates the oxidizing nature of the smelting process.  相似文献   
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This study presents apatite LA-ICP-MS U-Pb age and trace elements concentrations data from different granite types from the Tatra Mountains, Poland. Apatite from monazite and xenotime-bearing High Tatra granite was dated at 339 ± 5 Ma. The apatite LREE patterns reflect two types of magmas that contributed to this layered magma series. Apatite from a hybrid allanite-bearing diorite from the Goryczkowa Unit was dated at 340 ± 4 Ma with apatite LREE depletion reflecting the role of allanite and titanite during apatite crystallization. Apatite crystals from a hybrid cumulative rock from the Western Tatra Mountains were dated at 344 ± 3 Ma. Apatite is one of the main REE carriers in this sample and exhibit flat REE patterns. Taking into account the relatively low closure temperature of the U-Pb system in apatite (350–550°C), the c. 340 Ma apatite ages mark the end of high temperature tectonometamorphic activity in the Tatra Mountains.  相似文献   
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