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Chinese Science Bulletin 2003年第8期48卷 808-813页

作者： TANG Xianzan, CHEN Zhong,YAN Wen & CHEN Muhong The Open Laboratory of Geology and Paleoenvironment of Marginal Sea, south China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 5103.1, China The Open Laboratory of Geology and Paleoenvironment of Marginal Sea South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China

Three short geomagnetic excursions, the Go thenburg, Mono Lake and Mungo (or Maelifell) in the Brunhes Positive Polarity period, were revealed based on the studies of magnetostratigraphy, susceptibility (c) and d 18O of sediments in core WP 92-5 from the central temperature area of the Western Pacific Warm Pool (WPWP), and the ages of them are 12.111.3.kaBP, 25.024.0 kaBP, and 3..028.0 kaBP respectively. Furthermore, the Younger dryas (Yd) and Heinrich (H) cold events were also discov- ered in this core by the susceptibility record. The Yd cold event occurred at the depth of 3.22 cm with an age of 11.510.6 kaBP; H1, H2 and H3.cold events occurred at depths of 513. cm, 10891 cm and 140126 cm with ages of 15.113.0 kaBP, 25.022.1 kaBP and 3..628.2 kaBP respectively, which well correspond to the H1, H2, H3.events recorded by susceptibility of core SU90-09 from middle At- lantic, indicating that the susceptibility change of marine sediments can be an important sign of climatic frequent fluc- tuations.

关键词：磁化率沉积物西太平洋磁性地层学

Crystal Structure of Bridged dimer Complex of [Yb (H_2O)) (acac)_2 (Ac)]_2

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Chinese Journal of Structural Chemistry 1997年第5期16卷 371-375页

作者： SHEN Cheng(Chemistry department,Changsha Electric Power university, Changsha 410077) Chemistry department Changsha Electric Power University Changsha 410077 China

The title complex C24H3.O14Yb2(Mr=896. 62 ) crystallized in orthorhombic system, space group Pbcn with unit cell dimensions a=13. 478 (4), b=16. 161(7), c=15. 110(5); V=3.91. 2(2); Z=4; F(000) = 173.; dc=1. 810g. cm-3.μ= 17. 5 cm-1 (MoKa). The final R and Rw are 0.061 and 0.058 respectively. The title complex is a bridged dimer. The ligands that bridge two Yb(Ⅲ) centerions are the two acetatos in the complex and every Yb(Ⅲ) ion is eight-coordinated, being bonded to one O atom of one H,O molecule, four O atoms of two acetylacetonatos,two O atoms of an acetato and one O atom of another acetato. The coordination polyhedron of the Yb(Ⅲ) ion in the title complex is a dodecahedron.

关键词： acetylacetonato crystal structure bridged dimer complex tetraacetylacetonatodiaquo-μ-diacetatodiytterbium (Ⅲ)

The Yaean Metamorphic Core Complex and Extensional detachment Fault in Inner Mangolia, China

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Acta Geologica Sinica(English Edition) 1994年第2期68卷 125-135,227页

作者： Zheng Yadong and Zhang Qingdepartment of Geology, Peking university

The article describes the characteristics of the Yagan metamorphic core complex, especially the associated detachment fault and various extensional structures in its footwall. The age of the complex is discussed in some detail as well. The basic features of the Yagan metamorphic complex (Jurassic in age) are similar to those of the metamorphic core complex (Tertiary in age) in the Cordilleran area; they are as follows: (a) mylonitic gneisses in the footwall, (b) chloritized sheared mylonitic rocks, (c) pseudotachylites and flinty cataclasites or microbreccias, (d) unmetamorphosed or epimetamorphic rocks in the hanging wall with a layer of fault gouges or incohesive fault breccia next to the detachment fault. In contrast to its Cordilleran counterpart, however, there are many extensional faults with different styles (from dactile low-angle normal faults through brittle-ductile to brittle high-angle normal faults)in the footwall.

关键词： mylonite ultracataclasite pseudotachylite brittle-ductile fault in the footwall

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儿童运动行距预测能力的发展及影响因素

心理学报 1995年第4期27卷 371-378页

作者：裴剑涛沈家鲜龚剑飞华南师范大学心理系

采用计算机软件控制实验，以三种不同运动速度、四种不同运动行距组合呈现的光点运动为刺激物，每次光点在暴露运动一段行程后进入遮蔽，要求儿童判断光点到达目标位置时按键反应。主要结果表明：（１）儿童运动行距预测能力的发展表现... 详细信息

采用计算机软件控制实验，以三种不同运动速度、四种不同运动行距组合呈现的光点运动为刺激物，每次光点在暴露运动一段行程后进入遮蔽，要求儿童判断光点到达目标位置时按键反应。主要结果表明：（１）儿童运动行距预测能力的发展表现为５─８岁和１２─１９岁两个加速期及８─１２岁一个过渡期的发展模式。但在过渡期内，儿童的预测误差偏向有显著变化；（２）客体运动速度对儿童运动行距预测操作精度有显著影响，慢速下精度较高；（３）客体运动行距、被试性别并不影响儿童的行距预测操作；（４）５岁、１２岁与１９岁儿童多倾向于超前反应。

关键词：运动行距运动知觉运动表象预测误差值儿童

KINETICS OF REdUCTION IRON OXIdE IN CaO-SiO_2-Al_2O_3.Fe_tO SLAGS WITH CARBON SATURATEd IN MOLTEN IRON

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Acta Metallurgica Sinica(English Letters) 1997年第6期10卷 515-522页

作者： X.M. Yang d.B. Huang L. T. Kong T.J. Yang Y.S. Xie and d. G. Wang(Institute of Chemical Metallurgy, Chinese Academy of Sciences, Beijing 100080, China)(university of Science and Technology Beijing, Beijing 100083. China) Inst of Chemical Metallurgy Chinese Acad of Sciences Beijing China

The rate of reducing Fet O in CaO-SiO2-Al2O3.Fet O slags with carbon saturated in molten iron has been determined in a graphite crucible in the temperature range of 1673.1773.. The effects of temperature, slag basicity and FetO content on the reduction rate have also been discussed. Test results show that the reduction rate increases with increasing temperature or FEtO concentration in slags, and the reduction rate has a parabolic relation with the simple basicity or optical basicity of slag, the maximum reduction rate being observed at around CaO/SiO2=1.5 of molten slags. The reduction reaction order is 1. 73.or 1.80, and the reduction activation energy is 299.9 or 295.9 kJ/mol in regard to Fet O weight content or Fet O activity calculated by using regular solution model, respectively. The reduction rate of CaO-SiO2-Al2 O3.Fet O slags with carbon saturated in molten iron is in the range of 0.3.-3.48 mol-O/cm2·s.

关键词： CaO-SiO_2-Al_2O_3.Fe_tO slags reduction kinetics molten iron,Fe_tO activity

THEORY OF FLUId-SOLId COUPLEd FLOW THROUGH FRACTUREd LOW-PERMEABILITY OIL RESERVOIR ANd ITS APPLICATIONS

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Journal of Hydrodynamics 2003年第2期15卷 121-122页

作者： Ph.d.Candidate:Liu Jian junInstitute of Porous Media Mechanics, Wuhan Polytechic university, Wuhan 43.023. China Supervisor:Hu Yareng Institute of Porous Flow and Fluid Mechanics Chinese,Acade my of Sciences Institute of Porous Media Mechanics Wuhan Polytechic University Wuhan 430023 China

during the development of low permeability reservoirs. the interaction between fluid flow and rock mass deformation is obvious. On the basis of fluid mechanics in porous media and elasto plastic theory. the author presents an equivalent continuum model to simulate fluid flow in fractured low permeability oil reservoir coupled with geo stress. The model not only reflects the porosity change of matrix, but also the permeability change due to the opening and closing of fracture. By analyzing of simulation results, the changes in porosity and permeability and their effect on oil development are studied.

关键词： fluid solid interaction flow through porous media porosity permeability numerical simulation

ASYMPTOTIC PROPERTIES OF L_1-NORM KERNEL ESTIMATOR OF THE CONdITIONAL MEdIAN

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Systems Science and Mathematical Sciences 1992年第1期5卷 55-69页

作者： HONG Shengyan (Anhui university,Hefei 23.03.,China)

Let（X,Y） be a pair of Rd×R1-valued random *** thispaper we investigate the asymptotic properties of the L1-norm kernel estimator ofthe conditional median function of Y on *** appropriate regularity condi-tions,asymptotic normality and the optimal rates of convergence n（-1）/（2+d）and(n-1log n)1/（2+d） in the Lq（1（?）qd L∞-norms restricted to a compactset,respectively,are *** study shows that this estimator and the well-known Nadaraya-Watson’s kernel estimator of the conditional mean function of Yon X have the same asymptotic properties.

关键词： L1-norm kernel estimator conditional median rate of convergence asymptotic normality

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双氯芬酸钠迟效制剂的药动学

中国新药与临床杂志 2004年第6期23卷 342-345页

作者：李英谢冬玲周正王高峰高元勋郑州大学第二附属医院河南郑州450003 河南康利医药技术开发公司河南郑州450044 郑州大学癌症研究室河南郑州450052

目的 :以双氯芬酸钠普通肠溶片 (R)为对照 ,比较国产双氯芬酸钠迟效制剂 (T)的相对生物利用度和药动学。方法 :采用双交叉、自身对照的方法 ,将 2 4名受试者分为 2组 ,单剂量组分别口服T和R各 10 0mg ;多剂量组 ,每日分别口服T和R各10 0... 详细信息

目的 :以双氯芬酸钠普通肠溶片 (R)为对照 ,比较国产双氯芬酸钠迟效制剂 (T)的相对生物利用度和药动学。方法 :采用双交叉、自身对照的方法 ,将 2 4名受试者分为 2组 ,单剂量组分别口服T和R各 10 0mg ;多剂量组 ,每日分别口服T和R各10 0mg ,共 4d。结果 :单剂量组T和R的Cmax,Tmax,T1/2 ,MRT ,AUC0～τ分别为 (115 6±s 3. 1)和(3.10± 96 8) μg·L- 1,(3.0± 1.0 )和 (2 .3. 0 .5 )h ,(6 .6± 2 .3.和 (2 .9± 1.5 )h ,(12 .3. 2 .3.和 (4.4±1.0 )h ,(92 3.± 994 )和 (874 5± 12 16 ) μg·h·L- 1,T的F为 (10 7± 12 ) %。多剂量口服T和R的Cav,FI分别为 (3.3. 4 6 ) μg·L- 1和 (3.3. 6 4) μg·L- 1,(2 5 4± 82 ) %和 (40 4± 97) %。结论 :2种制剂口服吸收相似 ,迟效制剂具有峰谷浓度差异小 ,血药浓度波动幅度小等缓释药动学特征。

关键词：双氯芬酸迟效制剂药动学色谱法高压液相

Involvement of dNA methylation in endothelial apoptosis induced by cigarette smoke extract

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Involvement of DNA methylation in endothelial apoptosis indu...

An Assessment of Saltwater Intrusion in Coastal Regions of Lagos, Nigeria

中国生理学会第23.全国会员代表大会暨生理学学术大会

作者： Min YANG,Ping CHEN,Hong PENG,Qin SHEN,Yan CHEN department of Respiratory Medicine,the Second Xiangya Hospital of Central south university,Changsha 410011,China

＜正＞Cigarette smoking-related endothelial apoptosis plays an important role in the pathogenesis of chronic obstructive pulmonary disease（COPd）.The endothelial apoptosis which is not alleviated by smoking cessation will sustain at a high level throughout the course of disease,in which the exact mechanism remains still *** hypothesized that dNA methylation might account for the prolonged effects of smoking on endothelial *** in vitro experiment was performed to mimic the circumstance of endothelial cells in *** determine the effects of cigarette smoke extract（CSE） on endothelial apoptosis,human umbilical vascular endotheUal cells（HUVECs） were exposed to CSE at different concentrations for designed *** to investigate the role of dNA methylation in the CSE-induced endothelial apoptosis,HUVECs were incubated with demethylating reagent 5-aza-2’- deoxycytidinem（AZA） with and without *** apoptosis was assessed by terminal deoxynucleotidyl transferase -mediated dUTP nick end labeling（TUNEL） assay and caspase-3.*** activity was determined by *** polymerase chain reaction（PCR） and western blot were performed to evaluate the expression of COX subunitⅡ（COXⅡ） mRNA and protein,***-specific PCR was used to detect the methylation of COXⅡ.And direct nucleotide sequencing was used to detect methylated site of amplified MSP *** showed CSE significantly increased HUVEC apoptosis in a dose- and time-dependent manner, which was negatively correlated with COX activity and independent of caspase-3.*** suppressed COXⅡexpression at both mRNA and protein levels,with increased COXⅡmethylation in *** with AZA markedly attenuated COXⅡmethylation induced by *** results provided evidence that COX dysfunction might mediate the CSE-induced HUVEC apoptosis in which dNA methylation was involved.

关键词：

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Journal of Geoscience and Environment Protection 2024年第1期12卷 93-119页

作者： Obunadike Callistus Akerele d. daniel Abiodun O. Pelumi Olisah Somtobe Oloyede Kunle Obunadike S. Echezona Obunadike J. Chinenye department of Geosciences Freiberg University of Mining and Technology Freiberg Germany department of Construction Management University of Washington Seattle USA department of Civil Engineering Morgen State University Baltimore USA department of Geography University of Lagos Lagos Nigeria department of Biochemistry Anambra State University Uli Nigeria department of Geology Anambra State University Uli Nigeria

This paper explains various factors that contribute to saltwater intrusion, including overexploitation of freshwater resources and climate change as well as the different techniques essential for effective saltwater intrusion management. The impact of saltwater intrusion along coastal regions and its impact on the environment, hydrogeology and groundwater contamination. It suggests potential solutions to mitigate the impact of saltwater intrusion, including effective water management and techniques for managing SWI. The application of A.I (assessment index) serves as a guideline to correctly identify wells with SWI ranging from no intrusion, slight intrusion and strong intrusion. The challenges of saltwater intrusion in Lagos and the salinization of wells were investigated using the hydro-chemical parameters. The study identifies four wells (“AA”, “CMS”, “OBA” and “VIL”) as having high electric conductivities, indicating saline water intrusion, while other wells (“EBM”, “IKJ, and “IKO”) with lower electric conductivities, indicate little or no salt-water intrusion, and “AJ” well shows slight intrusion. The elevation of the wells also played a vital role in the SWI across coastal regions of Lagos. The study recommends continuous monitoring of coastal wells to help sustain and reduce saline intrusion. The findings of the study are important for policymakers, researchers, and practitioners who are interested in addressing the challenges of saltwater intrusion along coastal regions. We assessed the SWI across the eight (8) wells using the Assessment Index to identify wells with SWI. Wells in “CMS” and “VIL” has strong intrusions. A proposed classification system based on specific ion ratios categorizes water quality from good (+) to highly (-) contaminated (refer to Table 4). These findings underscore the need for attention and effective management strategies to address groundwater unsuitability for various purposes.

关键词： Hydro-Chemical data Analysis Saline Incursion Aquifer Sustainability and Management Coastal Regions Ground Water Intrusion