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THE DISCOVERY OF THE 400,000 YEARS CLIMATIC PERIOD IN chinese LOESS AND ITS BEARING ON PALEOCLIMATE

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中国科学院大学学报(中英文) 1992年第2期 207-214页

作者： Yu Zhiwei~(1)) (Department of geology,china University of Mining and Technology,Xuzhou 2.1008 Xi'an Laboratory of Loess and Quaternary geology,chinese academy of sciences,Xi'an 710061)Nie Gaozhong~(2.) (Department of Geography,Peking University,beijing 100871) Grade-82.graduate student,Graduate School of Academia SinicaGrade-83 graduate student,Graduate School of Academia Sinica

Magnetic susceptibility measurement was conducted at every10cm interval in the Baoji section,a 160 m thick loess-paleosoldeposit near the city of Baoji,Shaanxi *** independent timescale was constructed under control of geomagnetic polarity reversals byassuming that each paleosol and its underlying loess between twopaleomagnetic controls is a basic unit for linear interpolation based ontheir thickness,which indicate that the sediments represent the geologicalinterval 0 to 2.5 Ma *** power spectra of the susceptibilitytime series monitor strong peak at quasi-period of 400 ka,which is dueto the eccentricity of the Earth's orbit,as well as 100 ka,40 ka and2. ka periods,in agreement with the astronomical theory of climaticforcing.A primary mode for the Matuyama climatic history is sum-marized as periodic 400 ka fluctuations superimposed by variation ofshorter periods,in the lower Matuyama,the dominant shorter period is100 ka cycle while 40 ka cycle in the upper Matuyama.

关键词： periodicity of paleoclimate loess deposition magnetic susceptibility

Influence of MB-value of Manufactured Sand on the Shrinkage and Cracking of High Strength Concrete

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Journal of Wuhan University of Technology(Materials Science) 2009年第2期24卷 321-325页

作者：王稷良 Key Laboratory of Road Structure and Material Ministry of Communications (beijing) Research Institute of Highway Ministry of Communication

The relation between methylene blue （MB） value of MS and its limestone dust content and clay content was investigated. The effects of MB value ranging from 0.35 to 2.5 on the workability of fresh concrete and crack propagation characteristics at the age of 2. hours, and effects on the mechanical properties, dry shrinkage of the harden concrete were tested. The experimental results show that the MB value is not related with the limestone dust content of MS, but in direct proportion to clay content. With the increase of MB value, the concrete workability decreases, and the flexural strength and 7 d compressive strength reduce markedly, whearas the 2. d compressive strength is not affected. When the MB-value is less than or equal to 1.35, the change of the MB-value has a little influence on early plastic cracking and dry shrinkage property of concrete, but when the MB-value is more than 1.35, the tendency of plastic cracking and dry shrinkage is remarkable.

关键词： manufactured sand methylene blue value high strength concrete anti-cracking shrinkage

Distribution,formation and evolution of sand ridges on the East china Sea shelf

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Science china(Technological sciences) 2010年第3期53卷 822-828页

作者： ZHAO RenBao 1,2.SUN HaiTao 3,WU YaSheng 3 &ZHAO ChuanFeng 1,2.1MOE Key Laboratory of Petroleum Engineering,china University of Petroleum,beijing 102.49,china 2.Enhanced Oil Recovering Research Center,china University of Petroleum,beijing 102.49,china 3Faculty of Natural Resource&Information Technology,china University of Petroleum,beijing 102.49,china MOE Key Laboratory of Petroleum Engineering China University of Petroleum Enhanced Oil Recovering Research Center China University of Petroleum Faculty of Natural Resource & Information Technology China University of Petroleum

Influence of CO2.corrosion on reservoir mineralogical composition,pore structure and their mechanical characteristics was studied using XRD,SEM,rock tri-axial machine and core flow experimental *** was found that the corrosion effect was mainly attributed to rock texture and structure,fluid composition and external dynamical conditions in the experimental *** cores with bedding structures,their bedding surfaces were the preferential corrosion regions,because micro-cracks would evolve at these surfaces in the pressure-releasing ***,for cores with massive structures controlled by stable water environment,the CO2.corrosion would result in pore enlargement and secondary pore *** gas velocity from outlet showed sharp increase in the injection process of CO2.H2. *** could be explained by two changes caused by *** was the opening and closure of *** other was particle *** the corrosion time increased,both tensile strength and compressive strength decreased,which confirmed decrease of cementation *** should also be noted that permeability increase and micro-cracks generation would pose damage to the capacity of CO2.geological storage.

关键词： carbon dioxide geological storage mineralization enhanced oil recovery corrosion

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汉语普通话句子重音在时长方面的声学表现

心理学报 2003年第2期35卷 143-149页

作者：仲晓波杨玉芳中国科学院心理研究所北京师范大学心理学系北京100875 南开大学心理学研究中心 300071

研究包括两部分。在第一部分,通过对南10个发音人发音的148条句子中的4个词时长方面的声学特征的分析发现:(1)当句子重音强调词时,时长的增加主要集中在这个词的重读音节上;(2.当句子重音强调词的某个音节时,时长的延长主要集中在这个... 详细信息

研究包括两部分。在第一部分,通过对南10个发音人发音的148条句子中的4个词时长方面的声学特征的分析发现:(1)当句子重音强调词时,时长的增加主要集中在这个词的重读音节上;(2.当句子重音强调词的某个音节时,时长的延长主要集中在这个音节上。在第二部分,通过使用上述语句的知觉实验发现,句子重音强调词的语句和句子重音强调这个词的重读音节的语句相对于它们的语境是可以相互替换的,这种相互可替换性起因于这两种语句声学表现方面的相似性。

关键词：句子重音时长重读音节

A Procedure for Modeling Shallow Dislocation Sources with Tensional Component

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A Procedure for Modeling Shallow Dislocation Sources with Te...

中国科学院地质与地球物理研究所2.02.术年会

作者： HE Yu-Mei,WANG Wei-Min,YAO Zhen-Xing institute of geology and Geophysics,{2. academy of sciences,beijing 100101

The source terms of a tensile dislocation are presented in terms of the wave number and circular *** for displacements on the surface of a half-space due to an arbitrary oriented dislocation are also obtained by using the generalized ray *** result shows that the far-field waveforms contributed by tensile source are different from other sources. Considering that not all of the large earthquakes can be explained with the shear dislocation model, these expressions may be efficient in analyzing some earthquakes.

关键词： tensile source earthquakes modeling

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降雨径流对大理河流域系统泥沙输移比的影响

水土保持学报 2000年第Z1期14卷 19-27页

作者：陈浩中国科学院地理研究所北京100101

根据大理河流域水文测验资料 ,探讨了黄土丘陵沟壑区流域系统泥沙输移比的年际与次降雨时空变化特征和次降雨径流对泥沙输移比的影响及影响次降雨泥沙输移比的暴雨洪水能量转换机制。研究表明 ,从长远来看流域系统的侵蚀与产沙基本可以... 详细信息

根据大理河流域水文测验资料 ,探讨了黄土丘陵沟壑区流域系统泥沙输移比的年际与次降雨时空变化特征和次降雨径流对泥沙输移比的影响及影响次降雨泥沙输移比的暴雨洪水能量转换机制。研究表明 ,从长远来看流域系统的侵蚀与产沙基本可以达到平衡。但是 ,次降雨或分年度泥沙输移比有相当大的变幅 ,在短期内会经常存在泥沙的滞留和滞留的泥沙被重新侵蚀搬运而出现泥沙输移比小于 1和大于 1的情况。短期内流域系统中经常会处于侵蚀、输移、滞留及沉积的循环之中 ,这主要与降雨的时空分布和洪峰增减幅度及径流深度增减幅度密切相关。利用次降雨径流深度增幅比和洪峰增幅比不仅可以表征单位面积水流与沟道系统洪峰能量变化时对泥沙输移比的影响 ,并且具有极高的预报精度。

关键词：泥沙输移比降雨径流动力机制流域系统黄土丘陵沟壑区

MICRO/NANOFLUIDIC TECHNIQUES FOR ELECTROKINETICINJECTION AND SAMPLE PRECONCENTRATION

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MICRO/NANOFLUIDIC TECHNIQUES FOR ELECTROKINETICINJECTION AND...

IDENTIFICATION OF A METABOLITE OF BIPHENYLDIMETHYLDICARBOXYLE IN HUMAN URINE

庆祝中国力学学会成立50周年暨中国力学学会学术大会’2.07

作者： JIN Qinghui~(*,2.) ZHUANG Guisheng~(*,**) LlU Jing~(*,**) ZHAO Jianlong~* *(Shanghai institute of Microsystem and Information Technology,chinese {2. of sciences,Shanghai 2.0050,china) **(Graduate School of the chinese {2. of sciences,beijing 100049,china)

In this paper,micro/nanofluidic techniques for electrokinetic injection and sample preconcentration were developed. A novel double focus injection technique was designed for delivering high-quality sample plugs into the separation channel of a microchip capillary electrophoresis(μ-CE) *** microchip involved four focusing channels in which symmetrical potentials were loaded to form a unique parallel electric field

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chinese Chemical Letters 1996年第4期7卷 345-346页

作者： Ya Wei LI Xiu Yuan ZHU(institute of Materia Medica, chinese {2. of Medical sciencesbeijing 100050) institute of Materia Medica Chinese Academy of Medical Sciences Beijing 100050

The metabolism of biphenyldimethyldicarboxylate (BDD), an antihepatitis drug, was studied in human urine by deuterium labeled compound and GC-MS. It was found that the metabolite is mono-O-demethylated BDD, which conf...

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STRESS CORROSION CRACKING IN 16NiCo STEEL

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Acta Metallurgica Sinica(English Letters) 1997年第3期10卷 256-262页

作者： P.Zhang B.Z Guand B. Ling (beijing institute of Aeronautical Materials, beijing 100095, china) beijing Inst of Aeronautical Materials Beijing China

The dst of tempering temperature on strength, impact toughness, fracture toughness and stress corrosion cracking (SCC) behavior of 16NiCo Steel in an aqueons solutiou of 3.5 pct NaCl was stndied. The test compromise between strength, tonghness, and SCC resistance was obtained after 510℃ tempering. Under these conditions, KISCC is~75 MPam with fracture toughness of~75 MPam, impact toughness of~150J/cm2.and a gield strength of~1580 MPa. The improved stress corrosion crack-ing resistance at 510℃ tempering may be related to the loss of stress resulting from M2./matrix coherency and the recovery of the dislocalion substrvcture. These would lead to a decreased concentration of hydrogen.

关键词： streas corrosion secondary hardeing 16NiCo steel