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Ostracod fauna across the Permian-Triassic boundary at Chongyang, Hubei Province, and its implication for the process of the mass extinction

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Science China Earth Sciences 2010年第6期53卷 810-817页

作者： LIU Hao1, WANG YongBiao1, YUAN AiHua2. YANG Hao1, SONG HaiJun1 & ZHANG SuXin2. key laboratory of Biogeology and Environmental Geology of Ministry of Education, Wuhan 430074, China 2.State key laboratory of Geological Processes and Mineral Resources, Wuhan 430074, China key laboratory of Biogeology and Environmental Geology of Ministry of Education Wuhan China State key laboratory of Geological Processes and Mineral Resources Wuhan China

Thirty species of 10 ostracod genera were identified from 440 fossil specimens isolated through the hot acetolysis of the rock samples collected across the Permian-Triassic boundary at Chongyang section. Twenty species of 6 genera are found to occur in the limestone of Changxing Formation, and 11 species of 7 genera above the main faunal mass extinction horizon. The os-tracod assemblages identified at the Chongyang section are obviously different from those previously reported in the contem-poraneous microbialites in Guangxi and Chongqing regions, not only in the ostracod components but also in the abundance of filter-feeding ostracods relative to the deposit-feeding ostracods, an indicator of the oxygen level of the seawater. This spatial difference in ostracod assemblages might reflect the diversity of oceanic environmental conditions after the end-Permian mass extinction. Ostracods disappear at 2.0 cm below and near the main mass extinction horizon, and on the top of the microbialites, respectively, showing an episodic and gradual collapse process at the Chongyang section. The carbon isotope composition is found to appear at 2.0 cm below the main mass extinction horizon, indicating the initial deterioration of oceanic environment. Fluctuation of the carbon isotope composition is obviously related with the episodic evolution of ostracod species, but not with the abundance of ostracods.

关键词： ostracod microbialite Permian-Triassic mass extinction Chongyang

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中国对欧盟政策文件初析

外交学院学报 2004年第1期 49-53页

作者：冯仲平中国现代国际关系研究所北京100081

《中国对欧盟政策文件》的出台经历了一个长期酝酿和精心准备的过程。它既是中国对欧盟对华政策的一个积极回应,同时更体现了中国对欧盟重视程度的提高。欧洲一体化不仅增加了欧盟的实力,也增强了欧洲在世界范围内发挥更大作用的战略自... 详细信息

《中国对欧盟政策文件》的出台经历了一个长期酝酿和精心准备的过程。它既是中国对欧盟对华政策的一个积极回应,同时更体现了中国对欧盟重视程度的提高。欧洲一体化不仅增加了欧盟的实力,也增强了欧洲在世界范围内发挥更大作用的战略自信心。中国对欧盟的重视程度与欧盟一体化的程度是成正比的。共同的经济、政治及战略利益,加上双方加强更高层次合作的政治意愿将为中欧今后建立战略伙伴关系提供坚实的基础。

关键词：中欧关系欧盟一体化中国对欧盟政策

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镁氧水泥用于油井堵漏及暂闭的室内研究

西南石油大学学报（自然科学版） 2011年第5期33卷 152-156,202页

作者：李早元靳东旭周超葛红江郭小阳 "油气藏地质及开发工程"国家重点实验室.西南石油大学四川成都610500 中国石油大港油田采油工艺研究院天津大港300280

利用物相分析、电镜扫描等手段,研究了镁氧水泥在模拟井下工况水热环境中的热稳定性及酸溶蚀特性,分析和探讨了氯氧镁强度在水热环境中衰退的机理。研究结果表明:氯氧镁水泥在水热环境下5.1.8相易发生晶型转变,致使强度急剧衰减;而硫氧... 详细信息

利用物相分析、电镜扫描等手段,研究了镁氧水泥在模拟井下工况水热环境中的热稳定性及酸溶蚀特性,分析和探讨了氯氧镁强度在水热环境中衰退的机理。研究结果表明:氯氧镁水泥在水热环境下5.1.8相易发生晶型转变,致使强度急剧衰减;而硫氧镁水泥克服了氯氧镁水泥在水热环境下稳定性不良的缺陷,内掺5%碳酸钙后,硫氧镁水泥石2.h酸溶能力达95%以上,且具有较高的抗压强度,为产层封堵或暂闭提供了一种新型的暂闭封堵技术。

关键词：镁氧水泥强度暂闭封堵酸溶特性

Discussion on a problem in Gynecologic Oncology:Bone m etastases

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现代妇产科进展 1999年第3期 298-300页

作者： Geng Yi1 Sun Jianheng1 Jiang Sen2.(1 Dept. ofGynecologic Oncology,CancerHospitalofChineseAcadem y of MedicalSciences,10002. 2.ept. ofOBS/GYN,the Affiliated HospitalofShandong MedicalUniversity,2.0012.

Objective:To discuss a problem in gynecologic oncology:Bone m ***:contem porary literatures w ere review ed and analyzed by binding w ith the author’s experience. Results:Cancer induced bone diseases include prim ary osseous tum ors,non m etastatic effects of m alignancy on the skeleton and the effects of anticancer treatm ent on bone,but by far the m ost im portant problem clinically w as m etastatic bone *** spread ofcancer to bone occured in approxim ately 2.% of cancer patients w ho developed m etastatic *** m etastases could be lytic,blastic or a com bination of *** osteoclast activity had been associated w ith lytic bone m *** urine tests had been used to reflectosteolytic *** been associated w ith lytic bone m *** urine tests had been used to reflect osteolytic *** included calcium /creatinine and hydroxyproline/creatinine *** collagen crosslinked pyridinoline (PYD),deoxypyridinoline(DPD),and m ore recently the crosslinked N telepeptides(NTX) of type Icollagen had been proposed as m ore specific biochem ical m arkers than the above m entioned traditional m arkers of bone resorption. Biphosphonates w ere inhititors of osteoclast activity and their use resulted in decreased crosslinked values in patients w ith increased osteoclastic *** act by preventing the m aturation of precursor cells into osteoclasts w ere directly toxic to osteoclasts,and prevented osteoclasts from attaching to the bone ***:Metastatic bone disease is m ajor cause of m orbidity in patients w ith *** principal problem s are pain,pathological fractures,spinalcord com pression,hypercalcem ia and bone m arrow *** problem s are responsible for a particularly high proportion of days spentin hospitalas a result *** possible to predict w hich patients w ith bone m etastases are at high risk of developing the m ost serious com plication

关键词： Gynecologic oncology discussion on a prlblem Metastases,bonDiscussion on a problem in Gynecologic Oncology: Bone m etastases Geng Yi1 Sun Jianheng1 Jiang Sen2.(1 Dept. ofGynecologic Oncology,CancerHospitalofChineseAcadem y of MedicalScien

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论文学史的构成方式与文学史观

山东大学学报（哲学社会科学版） 2003年第1期 34-37页

作者：马立新大众日报社山东济南250014

本文从九十年代出版的两部当代文学史入手,分别从文学史的叙事方式、构成方式以及文学史观三个方面就文学史的写作方式进行历史纵向地梳理与探讨,进而试图寻求当下中国文学史的书写的可能性及可行性。

关键词：中国当代文学史写作方式文学史观