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51.
52.
Hydrothermal water–(pyroclastic) rock interactions were examined using flow-through experiments to deduce the effect of mass transport phenomena on the reaction process. A series of experiments were conducted over the temperature range 75–250°C, with a constant temperature for each experiment, and at saturated vapour pressure, to estimate the apparent rate constants as a function of temperature.
Based on the chemistry of analysed solutions, the water–rock interaction in the experiments was controlled by diffusion from the reaction surface and by the existence of a surface layer at the rock–fluid interface, which regulated the chemical reaction rate. The reaction progress depended to a high degree on flow velocity and temperature conditions, with element abundances in the fluid significantly affected by these factors. Mass transport coefficients for diffusion from the rock surface to the bulk solution have been estimated. Ca is selectively depleted under lower temperature conditions ( T < 150°C), whereas Na is greatly depleted under higher temperature conditions ( T > 150°C), and K reaction rates are increased when flow velocity increases. Using these conditions, specific alkali and alkali earth cations were selectively leached from mineral surfaces. The 'surface layer' comprised a 0.5–1.8 mm boundary film on the solution side (the thickness of this layer has no dependence on chemical character) and a reaction layer. The reaction layer was composed of a Si, Al-rich cation-leached layer, whose thickness was dependent on temperature, flow velocity and reaction length. The reaction layer varied in thickness from about 10−4 to 10−7 mm under high temperature/low fluid velocity and low temperature/high fluid velocity conditions, respectively. 相似文献
Based on the chemistry of analysed solutions, the water–rock interaction in the experiments was controlled by diffusion from the reaction surface and by the existence of a surface layer at the rock–fluid interface, which regulated the chemical reaction rate. The reaction progress depended to a high degree on flow velocity and temperature conditions, with element abundances in the fluid significantly affected by these factors. Mass transport coefficients for diffusion from the rock surface to the bulk solution have been estimated. Ca is selectively depleted under lower temperature conditions ( T < 150°C), whereas Na is greatly depleted under higher temperature conditions ( T > 150°C), and K reaction rates are increased when flow velocity increases. Using these conditions, specific alkali and alkali earth cations were selectively leached from mineral surfaces. The 'surface layer' comprised a 0.5–1.8 mm boundary film on the solution side (the thickness of this layer has no dependence on chemical character) and a reaction layer. The reaction layer was composed of a Si, Al-rich cation-leached layer, whose thickness was dependent on temperature, flow velocity and reaction length. The reaction layer varied in thickness from about 10
53.
Annabel Cooper 《Gender, place and culture : a journal of feminist geography》2009,16(2):121-138
This article uses a comparative analysis of two autobiographical texts to consider the ways in which the emotions and the imagination inform a sense of place. These autobiographies recount boyhoods in Point Chevalier, an Auckland suburb which embodies much that is emblematic of the mythology of early- to mid-twentieth-century childhoods in New Zealand. Both a modern suburb in a fast-growing city, and a richly particular coastal environment, it makes itself available as the setting for a childhood of the national imaginary. But as each of these narratives crosses the suburban terrain it produces a different understanding of what it meant to grow up as a male then, and there: in Halfway Round the Harbour Keith Sinclair never questions the fit between boy and place, or the certainty of his belonging and his identity; Peter Wells in Long Loop Home recalls a tumultuous boyhood increasingly marked by the threat of exclusion and intense family conflict. Between the two opposing trajectories of these texts, other possibilities are glimpsed. Place is created here by gender, sexuality and class; and masculinity is shaped and positioned differently for each of these boyhoods and the men who reflect on them. The affect of place marks the difference between these two Point Chevs. 相似文献
54.
天台徐一夔是元末明初的知名学者,一生以教书育人为业,是杭州府学声望卓著的教授。徐一夔传世的名字,是其官名,非其谱名,谱名已经轶失;近年研究徐一夔者或以始丰为其号,其实只是表示其乡里籍贯。稗史载徐一夔上表触怒朱元璋被斩,实系未成事实而被偏解作事实所致,系文人猎奇与发泄心理使然。 相似文献
55.
由新出金文资料及相关事例可知西周金文中普遍存在异人同名现象。而望簋与师望诸器、师汤父鼎与仲柟父诸器这两个典型例证则显示了以往西周铜器断代研究中忽视异人同名现象所带来的消极影响。因此,在铜器断代研究中运用人名系联法时,应该充分重视异人同名的可能性,尽可能综合考虑其他因素。 相似文献
56.
Neethi Padmanabhan 《对极》2012,44(3):971-992
Abstract: Supported by the labour geography framework, I analyse how spatial practices of labour shape the economic geography of capitalism, by looking into a model not at a global but at a very local scale of organisation and showing its effectiveness while confronting social actors organised at global or extra‐local scales. Questioning global stereotypes on economic responses to globalisation, I argue that labour becomes actively involved in the very process of globalisation and the expansion of capital, empirically demonstrating the relevance of this in the globalisation literature. I deal with one region—Kerala—and processes in its labour markets, taking the case of apparel workers in an export‐promoting industrial park. 相似文献
57.
《Journal of Geography in Higher Education》2012,36(2):164-173
This article offers an overview of visual methodology and its applications to geography in higher education. Drawings from an undergraduate mapping and map analysis course are used to concurrently highlight and deconstruct students' sense of place in the context of teaching and learning. As a pedagogical research tool, visual methods nurture self-reflection in learners, inform curriculum and instruction for diverse classrooms, and support the construction of meanings in geography. 相似文献
58.
Abstract: Indigenous activists and anarchist Settler people are articulating common ground in opposition to imperialism and colonialism. However, many anarchists have faced difficulties in Indigenous solidarity work through unintentional (often unwitting) transgressions and appropriations. Through the introduction of settler colonialism as a complicating power dynamic, we observe that anarchists bring unconscious spatial perceptions into their solidarity work. Further, Indigenous activists often perceive anarchists as Settler people first and foremost, which carries another set of spatial implications. We examine a number of examples of anarchist and Indigenous activism, at times empowering and at times conflictual, in order to reveal some general trends. Through an intensive synthesis of Indigenous peoples’ theories and articulations of place‐based relationships, we suggest that deeper understandings of these relationships can be of great importance in approaching solidarity work in place and with respect. 相似文献
59.
60.
“地方”概念对人文地理学各分支意义的辨识 总被引:1,自引:0,他引:1
地方是文化地理学的核心概念之一.当文化地理学与其他人文地理学分支交叉时, “地方”则为其他人文地理学分支提供了分析的基础.本文结合英美地理学刊物中若干涉及“地方”研究的文章,挖掘了地方的概念和内涵,以期对人文地理学诸分支提供学术支撑.本文的结论是:地方研究可支撑经济地理学文化转向和制度转向的研究;支撑区域地理学地方营销和旅游地理学旅游目的地营销的研究;支撑城市地理学公众参与式城市规划方案的制定;支撑政治地理学的选区策略制定.因此, “地方”作为文化地理学的核心概念,其存在意义是为其他学科提供学术营养,同时,文化地理学对地方的研究也可以使得文化地理学的社会应用能力更强. 相似文献