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11.
Fluid mixing induced by hydrothermal activity in the ordovician carbonates in Tarim Basin,China 下载免费PDF全文
Permian hydrothermal activity in the Tarim Basin may have been responsible for the invasion of hot brines into Ordovician carbonate reservoirs. Studies have been undertaken to explain the origin and geochemical characteristics of the diagenetic fluid present during this hydrothermal event although there is no consensus on it. We present a genetic model resulting from the study of δ13C, δ18O, δ34S, and 87Sr/86Sr isotope values and fluid inclusions (FIs) from fracture‐ and vug‐filling calcite, saddle dolomite, fluorite, barite, quartz, and anhydrite from Ordovician outcrops in northwest (NW) Tarim Basin and subsurface cores in Central Tarim Basin. The presence of hydrothermal fluid was confirmed by minerals with fluid inclusion homogenization temperatures being >10°C higher than the paleo‐formation burial temperatures both in the NW Tarim and in the Central Tarim areas. The mixing of hot (>200°C), high‐salinity (>24 wt% NaCl), 87Sr‐rich (up to 0.7104) hydrothermal fluid with cool (60–100°C), low‐salinity (0 to 3.5 wt% NaCl), also 87Sr‐rich (up to 0.7010) meteoric water in the Ordovician unit was supported by the salinity of fluid inclusions, and δ13C, δ18O, and 87Sr/86Sr isotopic values of the diagenetic minerals. Up‐migrated hydrothermal fluids from the deeper Cambrian strata may have contributed to the hot brine with high sulfate concentrations which promoted thermochemical sulfate reduction (TSR) in the Ordovician, resulting in the formation of 12C‐rich (δ13C as low as ?13.8‰) calcite and 34S‐rich (δ34S values from 21.4‰ to 29.7‰) H2S, pyrite, and elemental sulfur. Hydrothermal fluid mixing with fresh water in Ordovician strata in Tarim Basin was facilitated by deep‐seated faults and up‐reaching faults due to the pervasive Permian magmatic activity. Collectively, fluid mixing, hydrothermal dolomitization, TSR, and faulting may have locally dissolved the host carbonates and increased the reservoir porosity and permeability, which has significant implications for hydrocarbon exploration. 相似文献
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生态问题是当前政府和学术界都十分关注和重视的问题,也是关乎当今和子孙后代生存发展的重大问题。贵州的世居少数民族在漫长的社会、生产、生活的实践中,形成了本民族的生态知识和传统生态理念。本文着重从贵州少数民族的传统生态理念:和谐理念、保护理念、风水理念等方面进行论述。 相似文献
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陈尚胜 《中国边疆史地研究》2015,25(2):4-20,180
东亚地区传统国际秩序应称"封贡体系"较为周全。封贡关系的要义在于"事大"与"字小"。从中国明清王朝与朝鲜、琉球、越南等属国关系看,朝贡制度也是双边贸易、文化交流、边疆管控以及司法合作的基本机制,而在属国遭遇国家安全危机时,作为"上国"的明清王朝也积极进行政治外交和军事上的援救行动。不过,朝贡制度旨在建立"上国"与"属国"之间的主从关系,各个"属国"之间并没有围绕"上国"而形成合作联盟。因此,它在近代难以抗衡运用条约体系的西方列强以及日本在东亚地区的扩张。 相似文献
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陈晓伟 《中国边疆史地研究》2015,25(2):93-101,182
辽、金、元三朝皇帝每年皆例行驻夏活动,习称"夏捺钵",并在国家政治生活中占有举足轻重的地位,其中以炭山避暑最为引人注目。作者从四库本宋元文献中所见"阿延川"、"上京"两名入手,认为"阿延川"本作"爱阳川","上京"实乃"上陉"之误,两地皆位于炭山(金莲川草原)范围,并对清人认为"爪忽都"亦指金莲川的观点提出了不同的意见。 相似文献
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陈志刚 《中国边疆史地研究》2015,25(2):132-139,183
考察新疆哈密民田是了解近代哈密社会变迁的一条有效途径。道光年间,在林则徐主持下哈密出现了第一块民田。民国初年,哈密屯田民田化使民田面积进一步扩展。20世纪30年代,哈密回王世袭特权被取消,札萨克制下的土地朝民田方向发展。同时,哈密县政府限制清真寺的世俗权力,维吾尔人与汉人之间开始民田买卖,逐渐形成"你中有我,我中有你"的经济关系。 相似文献
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Chien-Min Chen 《Tourism Geographies》2019,21(1):78-101
ABSTRACTTo assess tourist motivations at the battlefield site on Kinmen Island of Taiwan, an empirical investigation was conducted. From a convenience sample, we collected 437 effective responses of respondents including domestic and international tourists with different cultural background in Kinmen. The structure of motivation was first examined via factor analysis. Then ANOVA analysis was applied to address the influence from demographic aspects such as gender, age, and nationality. Our results show that personal, spiritual, experience, physical, and emotional perspectives are five major sources of motivations. More importantly, age and nationality are confirmed to be two major dimensions to segment tourists in the context of battlefield tourism. Tourists with older age have higher motivations toward the battlefield site in comparison with young tourists. In addition, tourists with different cultural background based on different nationalities are significantly motivated by various motivational factors. The example of Kinmen contributes theoretically to a better understanding of the motivational attributes in a battlefield site, and how they represent a basis for increasing tourist perceptions. The motivational mechanisms and factors explored in this case can be incorporated into marketing strategies. Additionally, our results also provide a viable basis for the tourism authorities concerned to reevaluate the essence of its tourism industry in the context of battlefield resources and attractions. 相似文献
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ABSTRACT Rapid population growth and increasing water development costs have prompted many western governments to condition residential development approval on the adequacy of water supplies. We examine the effects of these regulations on housing supply in Colorado and New Mexico using fixed‐effects panel regressions. Our findings suggest that price‐based tools to ensure water availability may be a preferred regulatory alternative to quantity restrictions. Attempts to restrict groundwater basin access have not unambiguously corrected negative externalities related to growth. Meanwhile, Colorado cities' aggressive use of impact fees has facilitated water resource development, without limiting growth. 相似文献