全文获取类型
收费全文 | 471篇 |
免费 | 76篇 |
国内免费 | 234篇 |
专业分类
测绘学 | 2篇 |
大气科学 | 9篇 |
地球物理 | 115篇 |
地质学 | 590篇 |
海洋学 | 22篇 |
天文学 | 8篇 |
综合类 | 4篇 |
自然地理 | 31篇 |
出版年
2024年 | 3篇 |
2023年 | 9篇 |
2022年 | 11篇 |
2021年 | 18篇 |
2020年 | 19篇 |
2019年 | 22篇 |
2018年 | 11篇 |
2017年 | 31篇 |
2016年 | 27篇 |
2015年 | 23篇 |
2014年 | 30篇 |
2013年 | 52篇 |
2012年 | 33篇 |
2011年 | 23篇 |
2010年 | 28篇 |
2009年 | 36篇 |
2008年 | 25篇 |
2007年 | 38篇 |
2006年 | 56篇 |
2005年 | 40篇 |
2004年 | 30篇 |
2003年 | 27篇 |
2002年 | 21篇 |
2001年 | 23篇 |
2000年 | 30篇 |
1999年 | 23篇 |
1998年 | 12篇 |
1997年 | 15篇 |
1996年 | 22篇 |
1995年 | 11篇 |
1994年 | 12篇 |
1993年 | 1篇 |
1992年 | 6篇 |
1991年 | 2篇 |
1990年 | 4篇 |
1989年 | 1篇 |
1988年 | 3篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1984年 | 1篇 |
排序方式: 共有781条查询结果,搜索用时 156 毫秒
41.
The nature and distribution of fluids during amphibolite facies metamorphism, Naxos (Greece) 总被引:1,自引:0,他引:1
On the basis of fluid inclusion evidence, pervasive influx of deep-seated CO2 -rich fluids has been invoked to account for mid- to upper amphibolite facies (M2B ) metamorphism on the island of Naxos (Cyclades, Greece). In this paper, mineral devolatilization and melt equilibria are used to constrain the composition of both syn- and post-peak-M2B fluids in the deepest exposed levels of the metamorphic complex. The results indicate that peak-M2B fluids were spatially and compositionally heterogeneous throughout the high-grade core of the complex, whereas post-peak-M2B fluids were generally water-rich. The observed heterogeneities in syn-M2B fluid composition are inconsistent with pervasive CO2 -flushing models invoked by previous workers on the basis of fluid inclusion evidence. It is likely that few CO2 -rich fluid inclusions on Naxos preserve fluids trapped under peak metamorphic conditions. It is suggested that many of these inclusions have behaved as chemically open systems during the intense deformation that accompanied the uplift of the metamorphic complex. A similar process may explain the occurrence of some CO2 -rich fluid inclusions in granulite facies rocks. 相似文献
42.
43.
Cleaning with hierarchy of CO2‐based solvents is advantageous from an environmental point of view because CO2 is non‐flammable, virtually inert, and abundant. After cleaning, the only waste stuffs generated are the contaminants that are removed from the cleaned parts. The technology is especially well suited for precision cleaning applications in which parts have intricate geometries or for applications in which parts are sensitive to water or high temperature. This review will first introduce aqueous cleaning concepts and mechanism, which is helpful to understand how to design cleaning systems using high pressure CO2. Recent microelectronic processes for cleaning and rising of circuit wafers using CO2‐based solvents are the main focus of the review. Additional cleaning topics include dry cleaning, separation of dyestuffs, and extraction of contaminations from soils and regeneration of catalysts. 相似文献
44.
Wang Siyuan Xiao Qibing Zeng Jianguo Faculty of Earth Resources China University of Geosciences Wuhan 《中国地质大学学报(英文版)》2001,12(1)
-,The well-known Suichang silvengold field is located inZhejiang Province of SOutheast China. It is the largest silver-gold deposit associated with copper and zinc in the Cathaysianmetallogenic province.There are a series of silver-gold dePOsits in the shear zonesof Proterozoic gneiss terrene, Suichang region. The volcanicapparatus at Mesozoic has complicated rpineralization. Respectively, there are two pieces of understanding on the origin ofore-formigg nuid: (l ) metamorphic fluid (Lia… 相似文献
45.
人造气液包裹体方法在研究热液的物理化学性质方面较传统方法简便、易行。它可用于研究热液的等容线、不混溶性质及矿物在热液中的溶解度。本文解释了人造气液包裹体的合成方法和人造气液包裹体方法的原理,分述了应用此方法研究热液所取得的最新成果。此法不仅能用于研究热液的性质,也能用于其它方面的研究,具有广阔的前景。 相似文献
46.
47.
Abstract Quartz-hosted, synthetic CO2 -H2 O fluid inclusions behave as open systems with respect to diffusional transfer of hydrogen during laboratory-simulated metamorphic re-equilibration at 650, 750 and 825°C and 1.5 kbar total pressure with fO2 defined by the C-CH4 buffer. Microthermometry and Raman spectroscopy show that the initial CO2 -H2 O inclusions become CO2 -CH4 -H2 -H2O
inclusions after diffusive influx of hydrogen from the reducing confining medium. Measurable changes are observed in inclusion compositions after only 15 days of re-equilibration, implying significant hydrogen mobility at still lower temperatures over geological time spans. Results of synthetic inclusion re-equilibrium experiments have profound implications for the interpretation of natural fluid-inclusion data; failure to account for potential hydrogen migration in inclusions from high-temperature geological environments may lead to erroneous estimates of P-T, and/or the compositions of metamorphic fluids. 相似文献
inclusions after diffusive influx of hydrogen from the reducing confining medium. Measurable changes are observed in inclusion compositions after only 15 days of re-equilibration, implying significant hydrogen mobility at still lower temperatures over geological time spans. Results of synthetic inclusion re-equilibrium experiments have profound implications for the interpretation of natural fluid-inclusion data; failure to account for potential hydrogen migration in inclusions from high-temperature geological environments may lead to erroneous estimates of P-T, and/or the compositions of metamorphic fluids. 相似文献
48.
Natural gas generation model and its response in accumulated fluids in the Yinggehai basin 总被引:2,自引:0,他引:2
The generation of natural gases is much more complicated in comparison with liquid petro-leum in that natural gases could be generated from both humic and sapropelic organic matter at different stages and that natural gases could be organic and inorganic … 相似文献
49.
50.
Holdway DA 《Marine pollution bulletin》2002,44(3):185-203
A review of the acute and chronic effects of produced formation water (PFW), drilling fluids (muds) including oil-based cutting muds, water-based cutting muds, ester-based cutting muds and chemical additives, and crude oils associated with offshore oil and gas production was undertaken in relation to both temperate and tropical marine ecological processes. The main environmental effects are summarized, often in tabular form. Generally, the temporal and spatial scales of these studies, along with the large levels of inherent variation in natural environments, have precluded our ability to predict the potential long-term environmental impacts of the offshore oil and gas production industry. A series of critical questions regarding the environmental effects of the offshore oil and gas production industry that still remain unanswered are provided for future consideration. 相似文献