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Study on real working performance and overload safety factor of high arch dam

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Science china(Technological sciences) 2008年第S2期51卷 48-59页

作者： ZHANG GuoXin,LIU Yi & ZHOU QiuJing Department of Structures and Materials,china institute of Water Resources and Hydropower Research,beijing 100038,china 1. Department of Structures and Materials China Institute of Water Resources and Hydropower Research Beijing 100038 China

Considering the fact that high arch dams have problems such as complicated stress,high cost,and hazards after being damaged,this paper intends to study the effects of load,material strength,and safety analysis method on dam safety and working performance of arch *** this article,the effects of temperature,self weight exaction way and water loading on structure response are first discussed,and a more reasonable way of considering is then put *** taking into consideration the mechanical property of materials and comparing the effects of different yield criteria on overloading safety of high arch dams,this paper concludes that brittle characteristics of concrete should be fully considered when conducting safety assessment for high arch dams to avoid overestimating the bearing capacity of the *** comparing several typical projects,this paper works out a safety assessment system of multiple safety and relevant engineering analogical analysis methods,which is closer to the actual situation,and thus is able to assess the response of high arch dam structure in a more comprehensive way,elicit the safety coefficients in different situations,and provide a new way of considering the safety assessment of high arch dams.

关键词： high arch dam real working performance safety load strength safety assessment method

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DESIGN OF mm-WAVE PHASE-CORRECTING FRESNEL ZONE PLATE REFLECTOR ANTENNA WITH CONTINUOUS STRUCTURE

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Journal of Electronics(china) 1998年第3期15卷 278-283页

作者： Fan Zhongwei Lu Zhenwu Liao Jianghong(Changchun institute of Optics and Fine Mechanics, chinese academy of sciences, Changchun 130022)Zhang Junrong(Changchun institute of Geography, chinese academy of sciences, Changchun 130021)Chen Fangyun(National Defence Science & Industry Commision of china, beijing 100011)

Based on scalar diffraction optics theory, a new type of mm-wave antenna(diffraction antenna) phase-correcting Fresnel zone plate with continuous structure is described in this paper. It has the advantages of thinner thickness, lighter weight and design flexibility. The design theory and space shadow are discussed in details, and the measured results are presented. The results show that the properties of this kind of antenna is closed to paraboloid reflector.

关键词： Scalar diffraction optics Diffraction antenna Space shadow

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Tectonic Evolution of Tarim Plate and Surrounding Areas Since Late Paleozoic

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Continental Dynamics 1996年第2期 109-122页

作者： Liu Xun Fu Derong Yao Jianxin Ding Xiaozhong Wang Yong (institute of geology, chinese academy of Geological sciences, beijing 100037, china)Graham S.A. Chang E. Sobel E.(Department of Geological and Environmental sciences, Stanford University, S

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ＴｅｃｔｏｎｉｃＥｖｏｌｕｔｉｏｎｏｆＴａｒｉｍＰｌａｔｅａｎｄＳｕｒｒｏｕｎｄｉｎｇＡｒｅａｓＳｉｎｃｅＬａｔｅＰａｌｅｏｚｏｉｃ￥ＬｉｕＸｕｎ；ＦｕＤｅｒｏｎｇ；ＹａｏＪｉａｎｘｉｎ；ＤｉｎｇＸｉａｏｚｈｏｎｇ；ＷａｎｇＹｏｎｇ（Ｉｎｓｔｉｔｕｔ...

关键词： Sedimentary-tectonic evolution Tarim plate Late Paleozoic

THE SIGNALING PATHWAYS INVOLVED IN THE MATURATION OF HARD CLAM MERCENARIA MERCENARIA OOCYTES

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THE SIGNALING PATHWAYS INVOLVED IN THE MATURATION OF HARD CL...

Ⅸ International Congress on Medical and Applied Malacology

作者： ~(a b)Qing Wang ~aTao Zhang* ~aHongsheng Yang ~a Fusui Zhang a institute of Oceanology chinese academy of sciences Qingdao 266071 PR china b The Graduate School of chinese academy of sciences beijing 100049 PR china

＜正＞During the course of garnetogenesis in mollusck,fully grown oocytes generally arrest at prophase I（germinal vesicle stage）or metaphase I of *** hard clams Mercenaria mercenaria,5-HT（5-hydroxytryptamine,serotonin）can trigger prophase I-arrested oocytes to reinitiate meiosis and complete germinal vesicle breakdown（GVBD）.To identify the

关键词： 5-HT GVBD Signaling Pathway Oocytes Maturation Hard Clam

THE STUDIES OF MALIGNANT TRANSFORMATION OF HUMAN EPITHELIAL CELLS INDUCED BY DIETHYL-NITROSAMINE (NDEA) IN VITRO

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中国科学B辑(英文版) 1986年第11期29卷 1186-1191页

作者：黄明王秀琴王志华周传农吴旻 Cancer institute chinese academy of Medical sciences beijing beijing

This is the first report on the diethylnitrosamine-induced malignant transformaton of hu-man epithelial cells derived from fetal kidney. The transformed cells have prolonged life span and aneuploid karyotypes. They also form anchorage independent colonies in soft agar. With additional one or two NDEA treatments, those cells could elicit poorly differontiated carcinomas in immunosuppressed new-born rats. This experiment indicates that the human fetal kidney cells seem to be a good material for studying the mechanisms of carcinogenesis of human epithelial cell.

关键词： carcinogenesis fetal anchorage carcinomas poorly prolonged IN VITRO NDEA transformed elicit

Effect of gas emissions from Tianchi volcano(NE china) on environment and its potential volcanic hazards

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Effect of gas emissions from Tianchi volcano(NE China) on en...

中国科学院地质与地球物理研究所2006学术年会

作者： GUO Zhengfu,LIU Jiaqi,HAN Jingtai,HE Huaiyu,DAI Guoliang & YOU Haitao (institute of geology and geophysics,chinese academy of Science,beijing.10002.)

The Tianchi volcano in the Changbai Mountains is located on the boundary between china and North *** are many times of eruptions of the Tianchi volcano during the *** of its large eruptions occurred around 1000 years ago dated by 14C method and historical *** of products of the largest Tianchi volcanic eruption studied is characterized by comendi- tic Plinian fallout and unwelded ignimbrite,which are mainly distributed in china and North *** is about 4.4 km long and 3.4 km wide,which had filled with water(*** Lake).The Tianchi volcanic cone is about 2700 m high above sea *** Tianchi Lake is located on the summit of the volcanic cone,that is also highest peak of the Changbai Mountains in northeastern *** study analyzed Cl,F,S and H2O concentrations of melt inclusions in the phenocryst min- erals(anorthoclase and quartz) and co-existing matrix glasses using the electron microprobe and estimated environmental effect of Tianchi volcanic *** authors proposed a new method to evaluate future eruption of active volcano and estimate potential volcanic hazards based on contents of volatile *** this method,we made a perspective of future volcanic hazard in this re- gion.

关键词： Tianchi volcano volcanic gas environmental change volcanic hazard monitoring active volcano

Expression, purification and preliminary crystallographlc study on sulfur oxygenase reductase

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Expression, purification and preliminary crystallographlc st...

第七届全国酶学学术讨论会

作者： Mei Li, Shuang-jiang Liu, Dong-cai Liang, Wen-rui Chang institute of Biophysics, chinese academy of sciences, beijing, 100101 institute of Microbiology, chinese academy of sciences, beijing, 100080

A new enzyme was found from aerobically grown cells of the extremelythermophilic,facultatively anaerobic chemolithoautotrophic archaebacteriumDesulfurolobus ambivalens by *** in *** enzyme,which simultaneouslyproduced sulfite,thiosulfate and hydrogen sulfide from sulfur,was named sulfuroxygenase reductase(SOR).Later on,similar SOR proteins were also detected in

关键词： sulfur oxygenase reductase facultatively anaerobic bacteria crystallographic study

Sign-Changing and Multiple Solutions Theorems for Semilinear Elliptic Boundary Value Problems with Jumping Nonlinearities

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Acta Mathematica Sinica,English Series 2000年第1期16卷 113-122页

作者： Shujie Li Zhitao Zhang institute of Mathematics,Academia Sinica,beijing 100080,P.R.china institute of Mathematics Academia Sinica Beijing 100080 P.R. China

In this paper,we use the ordinary differential equation theory of Banach spaces and minimax theory,and in particular,the relative mountain pass lemma to study semilinear elliptic boundary value problems with jumping nonlinearities at zero or infinity,and get new multiple solutions and sign- changing solutions theorems,at last we get up to six nontrivial solutions.

关键词： Sign-changing solutions Dirichlet problems Multiple solutions Jumping nonlinearities

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Controlling Shell Thickness of PS/SiO2 Core-Shell Particles and Their Crystallization into 3-D Ordered Thin Film

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Controlling Shell Thickness of PS/SiO2 Core-Shell Particles ...

中国颗粒学会2006年年会暨海峡两岸颗粒技术研讨会

作者： WU Xiao-feng, CHEN Yun-fa, WEI Lian-qi, WANG Qi (Multi-phase Reaction Engineering Laboratory, institute of Process Engineering, chinese academy of sciences, beijing 100080, china Graduate University of the chinese academy of sciences, beijing 100049, china)

＜正＞PS/SiO2 particles with core-shell structure were synthesized by coating silica on surface of polystyrene （PS） colloidal particles. The reaction parameters, such asinitial tetraethyl orthosilicate （TEOS） concentration, water concentration and reaction temperature, have been investigated to control the thickness of silica shells. The shell thickness was prepositional to the square root of the initial concentration of TEOS and first increased with increasing water concentration, reached a maximum at about 2.0 mol/L and then started decreasing beyond that concentration. It is also found that the shell thickness decreases firstly with the reaction temperature added then tends to a constant. The so-synthesized PS/SiO2 core-shell particles were directly crystallized into 3-D ordered thin film, then sintered at 570 ℃ into the ordered macroporous thin film. Compared the conditional method, the present approach avoids repeatedly filling the precursor in the templetes and save time more.

关键词： PS/SiO2 core-shell particles ordered thin film