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1Source mechanism of strong aftershocks (M_s≥5.6) of the 2008/05/12 Wenchuan earthquake and the implication for seismotectonics显示文摘Dozens of >M5, hundreds of >M4, and much more >M3 aftershocks occurred after the 2008/05/12 Wenchuan earthquake, which were well recorded by permanent and portable seismic stations. After relocated with P arrival, the >M3 aftershocks show two trends of distribution, with most of the aftershocks located along the north-east strike consistent with Longmenshan fault system, yet there is a north-west trend around the epicenter. It seems that substantially more aftershocks occur in regions with crystalline bedrocks. Then we collected waveform data from National Digital Seismograph Network and regional seismograph network of China, and employed 'Cut and Paste' method to obtain focal mechanisms and depths of the big aftershocks (M≥5.6). While most of those aftershocks show thrust mechanism, there are some strike slip earthquakes in the northern-most end of the rupture. Focal mechanisms show that the events located on the southern part of central Beichuan-Yingxiu Fault (BY) are mainly thrust earthquakes, which is consistent with initial mechanism of the main shock rupture. In the north part the aftershocks along the BY are also dominated by thrust slip, which is quite different from the right slip rupture of the main shock. Around Qingchuan-Pingwu Fault, the focal mechanisms are dominated by right-slip rupture with large depths (~18 km). So we suspected that in the north part the main shock might rupture on two faults: Beichuan Fault and Qingchuan-Pingwu Fault. The complex pattern of aftershock mechanisms argues for presence of a complicated fault system in the Longmenshan area.ZHENG Yong1,2,MA HongSheng3,Lü Jian4,NI SiDao5,LI YingChun6 & WEI ShengJi2 1 Institute of Geodesy and Geophysics,Chinese Academy of Sciences,Wuhan 430077,China 2 Institute of Geophysics,Chinese Earthquake Administration,Beijing 100086,China 3 Institute of Earthquake Science,Chinese Earthquake Administration,Beijing 100086,China 4 Earthquake Administration of Jiangxi Province,Nanchang 330039,China 5 School of Earth and Space Science,University of Science and Technology of China,Hefei 230026,China 6 Earthquake Administration of Jiangsu Province,Nanjing 210014,China 2009Science China Earth Sciences2009,52,6:100
2中国5岁以下儿童死亡抽样调查显示文摘中国5岁以下儿童死亡抽样调查结果表明:1991年全国新生儿、婴儿、5岁以下儿童死亡率分别为33.07‰、50.19‰、61.03‰;城市分别为12.52‰、17.31‰、20.86‰;农村分别为37.90‰、58.02‰、71.08‰。农村占全国5岁以下儿童死亡的93.30%。婴儿死亡占5岁以下儿童死亡的80.20%,新生儿死亡占婴儿死亡的64.80%。提示5岁以下儿童死亡的前四位分类死因为新生儿疾病、呼吸系统疾病、意外事故及先天畸形;前四位疾病是肺炎、新生儿窒息、早产、腹泻。(The Nuitonul CollaborativeGroup for Survey of Dealhs of Under 5 ChJ7dren, Beijing100020.) 1994中华儿科杂志1994,32,3:111
3我国当代体育价值观的研究显示文摘围绕我国当代体育价值观这一研究主题,阐述了体育价值观的内涵,揭示了体育价值观与体育本质、功能、目的之间的辩证关系;对中西方体育价值观进行了比较研究,透过从生物体育价值观到人文体育观的嬗变,阐述人文体育观的科学性与实效性;在我国当代体育价值观的框架内,侧重论述体育的教育价值观、竞争价值观、休闲价值观与经济价值观,分析其对发展我国学校体育、竞技体育和社会体育的启示与要求,进而从我国当代体育价值观的视角提出我国体育改革与发展的思路与对策。陈琦 杨文轩 刘海元 鲁长芬 邓星华 张细谦 冯霞5 2006体育科学2006,26,8:169
4叶尔羌河流域气温、降水及径流变化特征分析显示文摘应用叶尔羌河流域的9个水文、气象站的观测资料,分析了叶尔羌河流域的气温、降水、径流的变化特征。结果显示:年代际时间尺度上叶尔羌河全流域以及帕米尔高原区、低山丘陵区、平原区在20世纪90年代以来呈明显的增暖、变湿趋势;44 a来年平均气温均呈显著的线性增加趋势,帕米尔高原区秋季温度上升最显著,平原区冬季升温最显著;帕米尔高原区与平原地区均以夏季降水的线性增湿最为显著;近50 a来,叶尔羌河流域中,仅提兹那甫河年径流量呈显著线性增加趋势,叶尔羌河年径流量虽然也呈线性增加趋势,但不显著;叶尔羌河与提兹那甫河年径流量自70年代以来呈反位相变化。孙本国 毛炜峄 冯燕茹 常涛 张丽萍 赵玲5 2006干旱区研究2006,23,2:63
5南充城市扩展中的景观生态安全格局显示文摘基于景观生态安全格局理论和RS、GIS技术,选择地形条件、洪水危害、土壤侵蚀、植被覆盖、地质灾害和生物保护6个要素作为城市空间扩展的生态约束条件,分析了南充市的生态安全等级分布,依据最小积累阻力模型,构建了生态廊道和生态节点等来加强生态网络的空间联系,在保障生态安全的基础上对城市合理的扩展趋势以及空间布局的优化进行分析.结果表明:南充市市域范围内整体生态安全状况较好,低生态安全水平区域较集中地分布于市区南部的嘉陵江下流区域和城郊西部山地;生态要素是南充市城市空间未来扩展的重要制约条件;南充市东部、北部存在发展空间,以卫星城镇模式增长可最大程度地保证南充市的生态安全.李绥 石铁矛 付士磊 周乐 刘淼 王炜5 2011应用生态学报2011,22,3:59
6Expression of vascular endothelial growth factor and its role in oncogenesis of human gastric carcinoma显示文摘AIM To establish the role of vascular endothelial growth factor (VEGF) in the oncogenesisof human gastric carcinoma more directly.METHODS The expression of VEGF and its receptor kinase-domain insert containing receptor (KDR) in human gastric cancer tissue were observed by immunohistochemical staining. VEGF levels were manipulated in human gastric cancer cell using eukaryotic expression constructs designed to express the complete VEGF165 complimentary DNA in either the sense or antisense orientation. The biological changes of the cells were observed in which VEGF was up-regulated or downregulated.RESULTS VEGF-positive rate was 50%, and VEGF was mainly localized in the cytoplasm and membrane of the tumor cells, while KDR was mainly located in the membrane of vascular endothelial cells in gastric cancer tissues and peri-cancerous tissue. In 2 cases of 50 specimens, the gastric cancer cells expressed KDR,localized in both the cytoplasm and membrane.Introduction of VEGF165 antisense into human gastric cancer cells ( SGC-7901, immunofluorescence intensity,31.6%)) resulted in a significant reduction in VEGFspecific messenger RNA and total and cell surface VEGF protein ( immunofluorescence intensity, 8.9%)(P<0.05). Conversely, stable integration of VEGF165 in the sense orientation resulted in an increase in cellular and cell surface VEGF (immunofluorescence intensity,75.4%) (P<0.05). Lowered VEGF levels were associated with a marked decrease in the growth of nude mouse xenografted tumor (at 33 days postimplantation, tomor volume: 345.40 ± 136.31 mm3) (P<0.05 vs control SGC7901 group: 1534.40 ± 362.88 mm3), whereas up-regulation of VEGF resulted in increased xenografted tumor size (at 33 days postimplantation, tomor volume: 2350.50 ± 637.70mm3) (P<0.05 vs control SGC-7901 group).CONCLUSION This study provides direct evidence that VEGF plays an important role in the oncogenesis of human gastric cancer.Du-Hu Liu Xue-Yong Zhang Dai-Ming Fan Yu-Xin Huang Jin-Shan Zhang Wei-Quan Huang Yuan-Qiang Zhang Qing-Sheng Huang Wen-Yu Ma Yu-Bo Chai Ming Jin Institute of Digestive Disease,Xijing Hospital,~2 Department of Gastroenterology,Tangdu Hospital,~3Department of Histology and Embryology,~4 Department of Microbiology,~5 Department of Biochemistry,Fourth Military Medical University,Xi’an 710033,Shaanxi Province,China 2001World Journal of Gastroenterology2001,7,4:37
7Clinical implication of VEGF serum levels in cirrhotic patients with or without portal hypertension显示文摘INTRODUCTIONAngiogenesisorformationofnewbloodvesels,isatightlyregulatedprocesinwhichbloodveselssupplygrowingtisuewithnutrient...Nimer Assy 1,4 , M Paizi 3,4 , D Gaitini 2, Y Baruch 1,4 and G Spira 3,4,5 1999World Journal of Gastroenterology1999,5,4:35
8含热电联产和风电机组的电网节能调度显示文摘针对采暖供给侧和需求侧,给出了一套基于智能电网的调度系统:包括某省级电网热电联产机组远程调度子系统和终端采暖负荷远程控制子系统。提出由电力驱动空调热泵分担部分热水式散热器的采暖负荷,据此减少采暖热水供给,增加采暖电力负荷。这就直接导致了电网内总电力负荷的增加和总采暖热水负荷的减少,改变了热电负荷的比例。基于新的采暖热水和电力负荷约束,建立了优化调度数学模型,实现了对热电联产机组和风力发电机组的节能调度。最后,基于我国现行电价和供暖热价,以确保各参与对象的经济利益不变为前提,讨论了风电的上网电价,证明了该方法的经济可行性。龙虹毓 马建伟 吴锴 杨玉龙 张竞博 苏岭 仇斌5 2011电力自动化设备2011,31,11:40
9Hyaluronic acid fragments evoke Kupffer cells via TLR4 signaling pathway显示文摘Kupffer cells, expressing toll-like receptor 4 (TLR4), play a central role in hepatic ischemia/reperfusion (I/R) injury. Hyaluronic acid (HA) fragments, degradative products of high-molecular-weight HA (HMW-HA), acquire the ability to activate immune cells under inflammatory conditions. Here we inves- tigated whether HA fragments could activate Kupffer cells and analyzed the underlying mechanism. Kupffer cells were isolated from wild-type mice (WT, C3H/HeN) and TLR4 mutant mice (C3H/HeJ) and HA fragments were produced by the methods of enzyme digestion and chromatography. Then Kupffer cells were stimulated by HA fragments or other control stimuli. The activation of Kupffer cells was estimated as the release of pro-inflammatory cytokines. The activation of p38 MAPK pathway of Kupffer cells was checked and blocking experiments were done as well. The results indicated that HA fragments acquired the ability to activate Kupffer cells in vitro, which was TLR4 dependent and not due to contamination of lipopolysaccharide. Experiments of p38 MAPK kinase inhibition by SB-203580 verified p38 MAPK was required in HA fragments induced Kupffer cells activation. This suggests that HA fragments, degradative products of one of the major glycosaminoglycans of the extracellular matrix, play critical roles in Kupffer cell activation mediated by TLR4 signaling pathway, which is, at least partially, de- pendent on p38 MAPK activation.ZHANG JinXiang1, WANG Hui2, XIAO Qing3, LIANG HuiFang4, LI ZhuoYa4, JIANG ChunFang1, WU HeShui5 & ZHENG QiChang5 1 Department of Emergency Surgery, Union Hospital Affiliated to Huazhong University of Science and Technology, Wuhan 430022, China 2 Department of Medical Genetics, Tongji Medical College Affiliated to Huazhong University of Science and Technology, Wuhan 430030, China 3 Department of Ophthalmology, Union Hospital Affiliated to Huazhong University of Science and Technology, Wuhan 430022, China 4 Department of Medical Immunology, Tongji Medical College Affiliated to Huazhong University of Science and Technology, Wuhan 430030, China 5 Department of General Surgery, Union Hospital Affiliated to Huazhong University of Science and Technology, Wuhan 430022, China 2009Science China(Life Sciences)2009,52,2:33
10湖北省湿地冬季水鸟多样性研究显示文摘报道了2004年1~4月湖北冬季水鸟调查结果,记录水鸟 66 种,种群数量 59 613 只,分属8目15科,其中列入国家重点保护的一级鸟类 4 种,115 只,国家二级 7 种,2 968 只.分析了冬季水鸟群落结构、分布和种群变动,并用生物多样性指数、物种丰富度与生物量3个不同的测度指标对其中12个湖泊的水鸟群落进行了评价,认为沉湖、梁子湖、龙感湖和网湖是较为成熟稳定的群落;并从沉湖东方白鹳(Ciconia boyciana)、龙感湖白头鹤(Grus monacha)、洪湖鸭科水鸟近40年的种群动态探讨了湿地水鸟现状,认为种群衰退趋势明显、湿地干扰和威胁严重.对此提出了加强湿地保护区的建设,理顺管理体制,合理规划与发展湿地产业和保护湿地资源对策.胡鸿兴 康洪莉 贡国鸿 朱觅辉 郑文勤 吴法清 何定富 李振文 耿栋5 2005长江流域资源与环境2005,14,4:34
11渭河下游河流沿线区域洪水灾害风险评价显示文摘区域洪水灾害风险评价是洪灾评估和管理的重要内容。依据灾害系统理论,利用G IS方法,综合分析了渭河下游对洪水灾害有影响的降水、地形、水系、过境洪水和防洪工程等自然致灾力和孕灾环境的影响度,以及承灾体遭受不同强度洪水可能损失程度的易损性影响度,运用层次分析法和因子叠加法,从自然和社会属性两个方面对洪灾风险进行了综合评价和分析。结果表明:研究区洪水灾害风险整体上以渭河下游干流为中心逐渐向两边递减,即离主干河流越近,风险越高,反之越低;从行政区划上来看,西安市城区和临潼区基本处于高风险区,而华县、华阴市和潼关县基本处于低风险区。李谢辉 王磊 谭灵芝 郑奕5 2009地理科学2009,29,5:34
12沈阳森林植物群落结构与其林内景观美学质量关系研究显示文摘模拟自然植物群落、恢复地带性植被是解决城市绿地退化问题的重要途径之一。探讨植物群落结构与其美学质量的关系是在城市绿地中模拟自然植物群落成功的关键。运用心理物理学派美景度测定与统计方法之一——美景度评估法,对沈阳地带性植被广泛分布的东陵公园、北陵公园、沈阳市植物园等地进行了森林林内景观美学质量评价,同时在对植物群落结构特征调查的基础上,利用数理统计分析方法将景观美学质量和群落结构特征的各项指标相联系,系统分析了主要群落结构特征指标对景观美学质量的影响。结果显示,森林林内景观美学质量受乔木树种比例、针叶树种比例、平均胸径、灌木数量、灌木频度、灌木盖度、草本盖度等因素影响。为城市森林建设、管理以及进一步研究提供依据。李俊英 闫红伟 唐强 祝跃5 2011西北林学院学报2011,26,2:31
13Draining Tangjiashan Barrier Lake after Wenchuan Earthquake and the flood propagation after the dam break显示文摘Tangjiashan Barrier Lake is one of the largest barrier lakes caused by the Wenchuan Earthquake. Its risk analysis, emergency plan and effect of the emergency plan are introduced in this paper. The dam height of Tangjiashan Barrier Dam is about 105 m, and the reservoir storage capacity is 3.2×108 m3. When the dam broke the flood peak were estimated to be larger than 48000 m3/s, which might cause a enormous disaster to the downstream cities and residents. A discharge channel with 13 m deep and 8 m wide was drug, so that the water may flow out of the lake before the dam breaks. As a result, the drainage and risk mitigation project are successful. During the drainage process, the flood peak was about 6500 m3/s, and about 1.6×108 m3 of water was drained off and the residual reservoir capacity was only 8.97×107 m3. A new channel with average width 100 m was formed, which can bear floods of 200 years frequency. The successful experience and the collected data can be used to deal with the similar natural disasters in future.LIU Ning1, ZHANG JianXin2, LIN Wei3, CHENG WuYI4 & CHEN ZuYu5 1 Ministry of Water Resources of the People’s Republic of China, Beijing 100053, China 2 Bureau of Hydrology of the Ministry of Water Resources of the People’s Republic of China, Beijing 100053, China 3 Sichuan Hydrographic and Water Resources Survey Bureau Chengdu 610031, China 4 HydroChina Chengdu Engineering Corporation, Chengdu 610072, China 5 China Institute of Water Resources and Hydropower Research, Beijing 100044, China 2009Science China(Technological Sciences)2009,52,4:29
14Invasive mechanism and management strategy of Bemisia tabaci(Gennadius) biotype B:Progress report of 973 Program on invasive alien species in China显示文摘Bemisia tabaci(Gennadius) biotype B,called a 'superbug',is one of the most harmful biotypes of this species complex worldwide.In this report,the invasive mechanism and management of B.tabaci biotype B,based on our 5-year studies,are presented.Six B.tabaci biotypes,B,Q,ZHJ1,ZHJ2,ZHJ3 and FJ1,have been identified in China.Biotype B dominates the other biotypes in many regions of the country.Genetic diversity in biotype B might be induced by host plant,geographical conditions,and/or insecticidal application.The activities of CarE(carboxylesterase) and GSTs(glutathione-S-transferase) in biotype B reared on cucumber and squash were greater than on other host plants,which might have increased its resistance to insecticides.The higher activities of detoxification enzymes in biotype B might be induced by the secondary metabolites in host plants.Higher adaptive ability of biotype B adults to adverse conditions might be linked to the expression of heat shock protein genes.The indigenous B.tabaci biotypes were displaced by the biotype B within 225 d.The asymmetric mating interactions and mutualism between biotype B and begomoviruses via its host plants speed up widespread invasion and displacement of other biotypes.B.tabaci biotype B displaced Trialeurodes vaporariorum(Westwood) after 4-7 generations under glasshouse conditions.Greater adaptive ability of the biotype B to adverse conditions and its rapid population increase might be the reasons of its successful displacement of T.vaporariorum.Greater ability of the biotype B to switch to different host plants may enrich its host plants,which might enable it to better compete with T.vaporariorum.Native predatory natural enemies possess greater ability to suppress B.tabaci under field conditions.The kairomones in the 3rd and 4th instars of biotype B may provide an important stimulus in host searching and location by its parasitoids.The present results provide useful information in explaining the mechanisms of genetic diversity,evolution and molecular eco-adaptation of biotype B.Furthermore,it provides a base for sustainable management of B.tabaci using biological and ecological measures.WAN FangHao1,ZHANG GuiFen1,LIU ShuSheng2,LUO Chen3,CHU Dong4,ZHANG YouJun4,ZANG LianSheng2,JIU Min2,Lü ZhiChuang1,CUI XuHong1,ZHANG LiPing4,ZHANG Fan3,ZHANG QingWen5,LIU WanXue1,LIANG Pei5,LEI ZhongRen1 & ZHANG YongJun1 1 State Key Laboratory for Biology of Plant Diseases and Insect Pests,Institute of Plant Protection,Chinese Acadeny of Agriculture Sciences,Beijing 100094,China 2 Institute of Applied Entomology,Zhejiang University,Hangzhou 310029,China 3 Institute of Plant and Environment Protection,Beijing Academy of Agricultural and Forestry Sciences,Beijing 100089,China 4 Institute of Vegetables and Flowers,Chinese Acadeny of Agricullare Sciences,Beijing 100081,China 5 Department of Entomology,China Agriculture University,Beijing 100094,China 2009Science China(Life Sciences)2009,52,1:30
15Modelling of multi-bodies in close proximity under water waves——Fluid resonance in narrow gaps显示文摘Viscous fluid model and potential flow model with and without artificial damping force(f=-μV,μ the damping coefficient and V the local averaging flow velocity) are employed in this work to investigate the phenomenon of fluid resonance in narrow gaps between multi-bodies in close proximity under water waves.The numerical results are compared with experimental data available in the literature.The comparison demonstrates that both the viscous fluid model and the potential flow model are able to predict the resonant frequency reasonably well.However the conventional potential flow model(without artificial damping term) significantly over-predicts the wave height in narrow gaps around the resonant frequency.In order to calibrate the appropriate damping coefficient used for the potential model and make it work as well as the viscous fluid model in predicting the resonant wave height in narrow gaps but with little computational efforts,the dependence of damping coefficient μ on the body geometric dimensions is examined considering the parameters of gap width Bg,body draft D,body breadth ratio Br and body number n(n = 2,3),where Br = BB/BA for the case of two bodies(Body A and Body B) with different breadths of BA and BB,respectively.It was confirmed that the damping coefficient used for the potential flow model is not sensitive to the geometric dimensions and spatial arrangement.It was found that μ∈ [0.4,0.5] may guarantee the variation of Hg/H0 with kh to be generally in good agreement with the experimental data and the results of viscous fluid model,where Hg is the excited wave height in narrow gaps under various dimensionless incident wave frequencies kh,H0 is the incident wave height,k = 2π/L is the wave number and h is the water depth.LU Lin1,2,TENG Bin3,CHENG Liang 4,SUN Liang5 & CHEN XiaoBo6 1 Center for Deepwater Engineering,Dalian University of Technology,Dalian 116024,China 2 State Key Laboratory of Structural Analysis for Industrial Equipment,Dalian University of Technology,Dalian 116024,China 3 State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian 116024,China 4 School of Civil and Resource Engineering,The University of Western Australia,Crawly 6003,Australia 5 Centre for Offshore Research and Engineering,Department of Civil Engineering,National University of Singapore,117576,Singapore 6 Research Department,Bureau Veritas,Neuilly-Sur-Seine,92570,France 2011Science China(Physics,Mechanics & Astronomy)2011,54,1:29
16采动影响下回采巷道底鼓控制技术显示文摘通过对回采巷道底板与煤柱的破坏关系分析,得到两帮煤体首先变形破坏是采动影响下回采巷道底鼓的直接原因,认为该类巷道的底鼓类型以挤压流动性底鼓为主;研究了底鼓的主要影响因素和现有底鼓防治措施,根据该矿9214巷道实际情况,提出了锚杆支护、全封闭工字钢的联合支护技术控制巷道底鼓,保障巷道围岩稳定。张科学 刘向增 郭坤 董辉5 2011煤矿安全2011,42,7:28
17Tectonic evolution of the Dabieshan orogen: In the view from polyphase deformation of the Beihuaiyang metamorphic zone显示文摘The Beihuaiyang metamorphic zone was formed by the Early Mesozoic collision of the North and South China Blocks. It consisted of the Foziling and Luzhenguan complexes and was thought to have never afforded a deep subduction. A similar feature of the deformation in the Dabieshan UHP metamorphic rocks implies that these different tectonic units share the same geodynamic background. The early stage of deformation can be preserved on account of their relatively shallower subduction than that for UHP rocks. On the basis of an analysis of the geo- logical structure and geochronological results, five deformational stages have been recognized: a D1-Early compressional deformation which represents the continental subduction; a D2-Early exhumation deformation producing a syn-convergence exhumation; a D3-Main deformation, represented by an exhumation deformation with Late Triassic age; a D4-Doming and its margin extensional gravity collapse deformation and finally a D5-regional extensional deformation of Cretaceous that was mostly introduced by the migmatization and plutonism.LIN Wei1, 2, Faure Michel3, WANG Qingchen1 & Arnaud Nicolas4 1. LTE, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 2. Department of Earth and Planetary Sciences, Graduate School of Science, Nagoya University, Japan 3. ISTO, UMR CNRS 6113, Batiment Géosciences, Orléans Université d’Orléans, 45067 Orléans Cedex 2, France 4. UMR 6524 'Magmas et Volcans', 5 Rue Kessler, 63000 Clermont-Ferrand, France 2005Science China Earth Sciences2005,48,7:25
18Lithosphere types in North China:Evidence from geology and geophysics显示文摘On the basis of the characteristics of geology and geophysics in North China, three types of lithosphere, namely, the cratonic, the orogenic and the rift lithospheres can be classified. In terms of petrological method (based on the information from Precambrian rock assemblages, igneous activities, deep-seated enclaves, etc.) and the relationship between seismic velocity and rock compositions, the crust-mantle petrological and chemical structure models can be set up. Researching results indicate that the geology and geophysics of North China platform bears the similar characteristics in comparison with those of the global typical cratons. The Eerduosi(Ordos) block located in the west of the North China Platform is a remnant of cratonic lithosphere after the North China platform had undergone “activation” in Mesozoic and “reconstruction” in Cenozoic times. The continental crust consists mainly of TTG rock assemblage while the subcontinental lithosphere mantle mainly consists of strongly depleted harzburgite. The craton was finally formed in late Archaean and early Proterozoic, and has been kept in stability up to present; its crustal-mantle petrological structures of lithosphere can be set up as a reference for the study of North China craton and even Sino-Korean craton. In the Mesozoic period, the middle and east areas of North China platform were activated in the Yanshanian orogenic process, the continental crust was reformed by material and heat-transfer of convective mantle and the original crustal TTG component was reconstructed to be granitic crust, and the subcontinental lithosphere man- tle was replaced by the Yanshanian harzburgite-lherzolite. The Yanshan-Taihang Mountains were the remnants of orogenic lithosphere after the rifting in eastern North China in Cenozoic. The present thickness of continental crust and lithosphere in the Yanshan-Taihang Mountains is not equal to their thickness during the Yanshanian orogenic movement because they had undergone the crustal extensional thinning in Cenozoic, however, the material and structure of lithosphere mantle-crust were formed during the Yanshanian orogenic movement. In the Cenozoic Period, the rift-type lithosphere, as represented by the North China plain, was formed by the continental rifting occurring in the eastern part of North China. The continental granitic crust, which had been “acidified” at the Yanshanian period, was basified again by the eruption of basalt magma along the continental rifting, and the subcontinental lithosphere mantle formed in Yanshanian was de- stroyed and replaced by the Himalayan mantle which consists mainly of lherzolite. Both the crust and the lithospheric mantle in the rift have undergone extensional thinning and thermal erosion at lithospheric-scale, the material and structure of the present mantle-crust lithosphere, attained from geophysical exploration, was formed in Cenozoic. The formation and evolution of litho- sphere in North China indicate that the material and heat transferred by convective mantle into the continental crust was the key for different types of lithosphere forming, and the crust-mantle petrologic structure was the records of lithosphere evolution, and it was the integrated results of the deep processes of the China continental dynamic system and the Pacific Plate subduction located in the eastern margin of the North China platform in Mesozoic-Cenozoic time.QIU Ruizhao1,2, DENG Jinfu3, ZHOU Su3, LI Jinfa4, XIAO Qinghui1,5, WU Zongxu6 & LIU Cui3 1. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China 2. Development and Research Center, China Geological Survey, Beijing 100037, China 3. China University of Geosciences, Beijing 100083, China 4. China University of Geosciences, Wuhan 430074, China 5. Information Center of Ministry of Land and Resources, Beijing 100812, China 6. Institute of Geology, State Seismological Bureau, Beijing 100029, China 2005Science China Earth Sciences2005,48,11:25
19特低-超低渗透砂岩储层微观孔喉特征与物性差异显示文摘为揭示特低-超低渗透砂岩储层微观孔隙结构与物性差异的关系,利用物性分析、铸体薄片、电镜扫描和高压压汞技术对鄂尔多斯盆地延长组3个典型的特低-超低渗透砂岩储层岩芯样品进行了实验测试。研究结果表明,特低-超低渗透砂岩储层喉道类型多样;但整体细小,对渗透率起主要贡献的较大喉道含量小是其物性较差的主要原因,同时微裂缝的发育也加剧了物性差异。统计对比发现,孔喉的分选系数在2.0~3.0,变异系数在0.15~0.3,对渗透率贡献相对较大。可见,储层物性是多种因素共同影响的综合反映,不同类型孔隙、喉道组成的储集空间,渗透率存在较大差异,物性差异正是孔喉特征差异的一种具体表现。高辉 孙卫 费二战 齐银 李达5 2011岩矿测试2011,30,2:26
20干旱区农田土壤水分地温变化规律及其相互关系显示文摘以干旱区农田灌溉后土壤水分、地温实测数据为基础,研究了其土壤水分、地温各自的变化规律及两者的相互关系。结果表明,各层含水量之间具有高相关性,基本达到了极显著的水平。这与土壤水分灌溉时由上而下的逐渐下渗,以及蒸发时由下而上的逐层上升有密切的关系。各层地温间的相关性大,除地面温度外,其余各层地温间的相关水平为显著或极显著水平,且相邻土层地温间均呈极显著相关。土壤水分及地温剖面垂直变化特征明显,并具有动态性。土壤水分含量大时,两者的垂直变异系数小,反之变异系数大。0~20 cm、地面(0 cm)分别为剖面含水量及地温变异强度的最大层,属中等变异强度。土壤水分及温度之间的负相关性明显。地面温度是预测表层、底层土壤水分的良好指标,利用回归分析法建立的土壤水分与地温间的函数关系可为推测土壤水分提供依据。张建兵 熊黑钢 李宝富 龙桃5 2013干旱地区农业研究2013,31,2:25
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