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Strontium and boron isotopic constraint on the marine origin of the Khammuane potash deposits in southeastern Laos

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Science Bulletin 2010年第Z2期 3181-3188页

作者： TAN HongBing 1,2.MA HaiZhou 3,LI BinKai 3,ZHANG XiYing 3 &XIAO YingKai 3 1School of Earth Science and Engineering,Hohai university,Nanjing 2.0098,china 2.State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai university,Nanjing 2.0098,china 3Qinghai Institute of Salt Lakes,chinese academy of sciences,Xining 810008,china

Since 2.06,we have conducted a geological exploration of the Khammuane area in southeastern *** thick sequences of potash deposits containing sylvite and carnallite were discovered from drilling Paleocene strata of the Thangon Formation(E1tg).To constrain the origin of the brine that formed thick sequences of salt mineral deposits,we measured the strontium and boron isotope composition of some salt minerals in the potash *** isotope composition of halite-and potash-associated minerals in the Khammuane potash deposit varied from 19.91%to 31.01‰,which differs significantly from continental evaporates(-6.83‰--5.79‰)but is very close to that of salts precipitated from evapo-concentrated seawater(10‰-36‰).The 87Sr/86Sr ratios(0.707542.to 0.709461)of salts were also close to the values of Paleocene seawater(0.70772.to 0.707830).The content of Br-(0.01%-0.2.%)and Br×103/Cl ratios(0.10-0.52.of halite were>10 times higher than that of common continental *** characteristics indicate clearly that the Laos potash deposits were deposited from *** small variation in boron and strontium isotopes in all salt sedimentary sequences(gypsum-halite-potash-halite)also suggests that the recharge source should be stable and the effects of other continental water mixing are ***-scale potash deposits are commonly precipitated from ***,the results of recent regional drilling work and geochemical research suggest extensive potash resources could occur in the Thangon Formation of southeastern Laos.

关键词： potash deposit strontium isotope boron isotope marine origin Laos

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轻质复合材料及结构热膨胀调控设计研究进展

科学通报 2017年第1期62卷 47-60页

作者：韦凯裴永茂湖南大学机械与运载工程学院工程力学系长沙410082 北京大学工学院力学系北京100871

热膨胀系数是材料热物理性能的重要参数.在温度剧烈变化服役环境下,航空航天工程中卫星、高超声速飞行器以及精密仪器仪表,微电子封装中大量结构的热变形需要精确的控制.发展热膨胀可调控的材料具有重要的科学意义和工程应用价值.轻质... 详细信息

热膨胀系数是材料热物理性能的重要参数.在温度剧烈变化服役环境下,航空航天工程中卫星、高超声速飞行器以及精密仪器仪表,微电子封装中大量结构的热变形需要精确的控制.发展热膨胀可调控的材料具有重要的科学意义和工程应用价值.轻质复合材料凭借其轻量化,力学性能优异且热膨胀系数可设计的优点已成为热变形控制领域的重要材料.本文首先概括了材料和结构的热变形控制在工程中的重要应用以及已有低、负膨胀均质材料的研究现状.其次详细介绍了层合、颗粒增强及拓扑优化复合材料的热膨胀设计研究成果.最后重点综述了轻质点阵复合材料的几何结构设计方法,热膨胀调控机理,制备工艺及实验表征的最新研究成果.

关键词：复合材料热膨胀调控点阵结构优化设计轻量化

Pool-formation and secondary change of biodegraded viscous oils:Case study of reservoir section in the ZhengjiaWangzhuang Oilfield, Jiyang Depression

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chinese Science Bulletin 2004年第S1期49卷 39-49页

作者： WANG Zhenqi, PENG Ping’an, YU Chiling, LU Hong, ZOU Yanrong, ZHANG Linye & LIU Junmin State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, chinese academy of {2., Guangzhou 510640, china Department of Earth Science, Yangtze university, Jingzhou 43402., china Research Institute of Geology, Shengli Oilfield Co. Ltd., SINOPEC, Dongying 2.7015, china chinese Acad Sci State Key Lab Organ Geochem Guangzhou Inst Geochem Guangzhou 510640 Peoples R China Yangtze Univ Dept Earth Sci Jinzhou 434023 Peoples R China Shengli Oilfeld Co Ltd Res Inst Geol SINOPEC Dongying 527015 Peoples R China

It is demonstrated by various geochemical indexes that the Zhengjia-Wangzhuang Oilfield with viscous crude oil in the Jiyang Depression has been sourced from the contribution of matured source rocks in the upper Es4. The principal cause leading to the densification of crude oils would be biodegradation, with the degradation level of crude oils being ranked as 2.8; vertically, the biodegradation level increases from the top to bottom of the oil column, with a distinctive biodegradation gradient occurring. Calculated parameters of sterane, terpane and methyl-phenanthrene have indicated that the source-rock’s maturity of crude oils and asphaltic sands ranges from 0.7 to 0.9, and based on the calculation of Easy Ro model, the temperature of hydrocarbon generation in the source rock would be within 12.-140℃, which coincides with the measurements of reservoir inclusions. The measured homogenization temperature would represent the generation temperature of the source rock, and be fairly different from that

关键词： viscous oil biodegradation time of pool-formation time of degradation Jiyang Depression.

Synthesis and Crystal Structure of 1-D Chain Copper（Ⅱ） Complex: [Cu（L）Cl2._n （L=2.5-Di-2.pyridyl-1,3,4-oxodiazole）

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chinese Journal of Structural Chemistry 2004年第2期 141-144+121页

作者： LI Jian-Ronga, b GUO Guo-Conga② BU Xian-Heb② HUANG Jin-Shuna a (State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, The chinese academy of {2., Fuzhou 350002. china) b (Department of Chemistry, Nankai university, Tianjin 300071, china)

The title complex, [Cu(L)Cl2.n (L = 2.5-di-2.pyridyl-1,3,4-oxodiazole) 1, has been obtained from the reaction of 3,6-di-2.pyridyl-1,2.4,5-tetrazine (bptz) and CuCl2.H2. in a mixture solvent of CH3CN and CH2.l2.(L is generated from the metal-assisted hydrolysis reaction of bptz) and structurally characterized. It crystallizes in space group C2.c of monoclinic system with cell parameters: a = 9.812.2., b = 12.679(3), c = 11.111(2. ? b = 103.92.3)? V = 1341.6(5) 3, Z = 4, Dc = 1.776 g/cm3, Mr = 358.66, F(000) = 716, ?= 2.02. mm1 and S = 1.004. The final R = 0.0346 and wR = 0.0938 for 1011 observed reflections with I > 2.I). The Cu(Ⅱ) ion is six-coordinated by four N atoms of two L ligands and two Cl ions in a distorted octahedral geometry. The ligand L acts as a bis-bidentate ligand to bridge the Cu(Ⅱ) ions, resulting in an infinite chain structure.

关键词： copper(Ⅱ) complex synthesis crystal structure 1-D chain

记忆编码与特异性效应之间关系的ERP研究(英文)

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心理学报 2004年第4期36卷 455-463页

作者：郭春彦朱滢丁锦红范思陆首都师范大学心理系北京100037 北京大学心理系北京100871 中国科学院北京100039

通过事件相关电位 (ERPs)探讨了在“学习$C再认”模式条件下的记忆编码与特异性效应之间的关系。选择首要特异性特征为深、浅加工 ,次要特异性特征为高、低词频。研究结果表明 ,(1 )行为数据支持了低频词的再认比高频词更精确 ;深加工... 详细信息

通过事件相关电位 (ERPs)探讨了在“学习$C再认”模式条件下的记忆编码与特异性效应之间的关系。选择首要特异性特征为深、浅加工 ,次要特异性特征为高、低词频。研究结果表明 ,(1 )行为数据支持了低频词的再认比高频词更精确 ;深加工的再认比浅加工更精确 ,并且深加工存在着显著的字频效应 ,浅加工没有显著的字频效应。 (2.)低频词比高频词有更大的ERP晚正成分 (LPC) ;在低频词条件下 ,存在着显著的相继记忆效应 ,随后再认正确的ERPs比随后再认不正确的ERPs更正。因此。

关键词：事件相关电位特异性效应记忆编码相继记忆效应词频效应

TEMPERING RESPONSE OF A DEFORMED LOW CARBON DUAL PHASE STRUCTURE

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Acta Metallurgica Sinica(English Letters) 1995年第2期8卷 79-83页

作者： JIN Man JIANG Zhonghao NAN Shenghui HU Jiandong LIAN jianshe(Jilin university of Technology,Changchun,china)(Manuscript received 8 February 1995)Correspondent:LI Geping,(Institute of Metal Research,{2. academy of sciences,Shenyang 110015,china)

The low carbon dual phase structure was cold de formed first,then was tempered at 2.0 to 600℃.The variation in strength and ductility during tempering of the steel was *** was found that a fter the de formed dual phase structure was tempered at 2.0 to 600℃, with the increase in the tempering temperature the tensile strength decreases rapidly;the lotal elongation remains constant at 2.0 to 500℃ but began to rise dramatically at a critical temperature between 500 and 600℃.However,when the non-deformed dual phase structure was tempered at the same temperature range,the tensile strength decreases and the total elongation increases continuously with the increase of *** was demonstrated from TEM analysis that precipitating carbides density along the boundaries ofmartensite lath and the recrystallized grains are responsible for the tempering response ofthe de formed dual phase structure.

关键词： de formed dual phase structure tensile property tempering

A NEW MEASURE FOR DIRECT MEASUREMENT OF THE BED SHEAR STRESS OF WAVE BOUNDARY LAYER IN WAVE FLUME

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Journal of Hydrodynamics 2007年第4期19卷 517-524页

作者： HUO Guang WANG Yi-gang YIN Bao-shu YOU Zai-jin Key Laboratory of Coastal Disaster and Defense Ministry of Education Hohai University Nanjin 210098China Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China Coastal Unit. Department of Natural Resources Dangar NSW Australia

In this article, a shear plate was mounted on the bottom in a wave flume and direct measurements of the smooth and rough bed shear stress under regular and irregular waves were conducted with the horizontal force exerted on the shear plates by the bottom shear stress in the wave boundary layer. Under immobile bed condition, grains of sand were glued uniformly and tightly onto the shear plate, being prevented from motion with the fluid flow and generation of sand ripples. The distribution of the bottom mean shear stress varying with time was measured by examining the interaction between the shear plate and shear transducers. The relation between the force measured by the shear transducers and its voltage is a linear one. Simultaneous measurements of the bottom velocity were carried out by an Acoustic Doppler Velocimeter （ADV）, while the whole process was completely controlled by computers, bottom shear stress and velocity were synchronously measured. Based on the experimental results, it can be concluded that （1） the friction coefficient groews considerably with the increase of the Reynolds number, （2. the shear stress is a function varying with time and linearly proportional to the velocity. Compared with theoretical results and previous experimental data, it is shown that the experimental method is feasible and effective, A further study on the bed shear stress under regular or irregular waves can be carried out. And applicability to the laboratory studies on the initiation of sediments and the measurement of the shear stress after sediment imigration.

关键词： wave boundary layer friction coefficient,shear plate shear stress Acoustic Doppler Velocimeter (ADV)

Effects of non-Gaussian noise on the dynamical properties of a logistic system

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chinese Physics B 2013年第6期22卷 228-232页

作者：王参军 Nonlinear Research Institute Baoji University of Arts and Sciences

The dynamical properties of a tumor cell growth system described by the logistic system with coupling between non- Gaussian and Gaussian noise terms are investigated. The effects of the nonextensive index q on the stationary properties and the transient properties are discussed, respectively. The results show that the nonextensive index q can induce the tumor cell numbers to decrease greatly in the case of q 〉 1. Moreover, the switch from the steady stable state to the extinct state is speeded up as the increases of q, and the tumor cell numbers can be more obviously restrained for a large value of q. The numerical results are found to be in basic agreement with the theoretical predictions.

关键词： logistic growth system non-Gaussian noise dynamical properties

El Ni?o发展年和La Ni?a年东亚夏季风季节内变化的比较

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气候与环境研究 2018年第3期23卷 321-331页

作者：薛峰段欣妤苏同华中国科学院大气物理研究所国际气候与环境科学中心北京100029 中国科学院大学北京100049 福建省气象台福州350001

基于1979~2.13年多种再分析资料,合成分析了El Ni?o发展年和La Ni?a年东亚夏季风的季节内变化。结果表明,东亚夏季风在两种情况下呈现出不同的季节内变化特征。在El Ni?o发展年,初夏期间高纬度地区出现偏北风异常,造成东亚地区位势高度... 详细信息

基于1979~2.13年多种再分析资料,合成分析了El Ni?o发展年和La Ni?a年东亚夏季风的季节内变化。结果表明,东亚夏季风在两种情况下呈现出不同的季节内变化特征。在El Ni?o发展年,初夏期间高纬度地区出现偏北风异常,造成东亚地区位势高度场偏低,西太平洋副热带高压偏东,但均不显著。盛夏期间,El Ni?o强迫造成中太平洋对流增强,副热带西太平洋出现气旋异常,位势高度显著降低,副热带高压明显偏东。与此不同的是,La Ni?a年春季暖池海温偏高,造成夏季对流偏强,西太平洋地区位势高度场偏低,副热带高压减弱东退。此外,La Ni?a年东亚夏季风的季节内变化较为复杂,6月异常较弱,7月达到最强,8月又开始减弱。因此,虽然El Ni?o发展年和La Ni?a年夏季平均副高异常有一定的相似性,但季节内变化则有很大差异,其成因也完全不同。

关键词：东亚夏季风西太平洋副热带高压季节内变化 El Nino发展年 La Nina年