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Tunable DBR Lasers Fabricated by Selective Area Growth Technique

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chinese Journal of Lasers 2000年第5期9卷 12-16页

作者： LIU Guoli ZHANG Jingyuan WANG Xiaojie ZHANG Baijun WANG Wei (National Research Center for Optoelectronic Technology, institute of Semiconductors,The chinese Academy of {2., {3. 100083. China) Received Jan. 11, 2.00 Revised manuscript rece 中科院半导体所国家光电技术研究中心北京

The tunable ridge waveguide distributed Bragg reflector (DBR) lasers grown by selective area growth and designed for WDM communication systems at 1.55 μm is reported. The threshold of DBR lasers is 62.mA and the output power is more than 8 mW; the isolation resistance between the active region and Bragg region is 3. kΩ; the tuning range is 6.5 nm which can provide 6 WDM channels with a 100 GHz spacing; in the tuning range, the single mode suppression ratio (SMSR) is more than 3. dB and the output power variation of different wavelengths is less than 3.dB.

关键词： selective area growth MOCVD tunable laser DBR laser

稀土碱土过渡金属类钙钛石(A_2.O_4)复合氧化物催化剂的固态物化性质及对NO_x消除反应的催化性能

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中国稀土学报 2003年第Z2期21卷 35-39页

作者：赵震杨向光吴越石油大学(北京)重质油国家重点实验室北京102249 中国科学院长春应用化学研究所

用柠檬酸络合法制备了多个系列的类钙钛石(A2.O4)结构的复合氧化物催化剂,系统地研究探讨了该类催化剂的晶体与光谱结构、缺陷结构、对NO和CO等小分子的吸附性能、对氧的吸脱性能及氧化还原性能和稳定性,同时考察了上述多个系列催化剂... 详细信息

用柠檬酸络合法制备了多个系列的类钙钛石(A2.O4)结构的复合氧化物催化剂,系统地研究探讨了该类催化剂的晶体与光谱结构、缺陷结构、对NO和CO等小分子的吸附性能、对氧的吸脱性能及氧化还原性能和稳定性,同时考察了上述多个系列催化剂对NO直接分解和CO还原NO反应的催化性能。发现Ni系A2.O4复合氧化物是NO直接分解的高活性催化体系,特别是LaSrNiO4-λ催化剂具有很高NO的分解活性,其活性高于文献报道Y Ba CuO/MgO的和Co系ABO3.化剂。同时发现LaSrCuO4-λ具有较高的CO还原NO催化性能。提出了在类钙钛石复合氧化物催化剂上NO分解和还原反应统一的氧化还原反应机制,并比较了两个反应的异同点,确认了氧空位在上述反应中的作用。并较深入的探讨了取代效应、过渡元素、稀土元素和结构效应对NO分解和CO还原NO反应的影响机制。本文分析总结了作者在类钙钛石(K2.iF4)结构复合氧化物的固态物化性质及对NOx消除反应的催化性能方面的基础性研究结果。

关键词：类钙钛石结构(A2.O4)复合氧化物碱土过渡金属固态物化性质 NOx消除反应催化性能稀土

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酒西坳陷油藏地球化学研究

新疆石油地质 2005年第1期26卷 39-43页

作者：胡咏张大江于兴河程克明熊英杨智明中国地质大学北京100083 中国石油石油勘探开发研究院北京100083 中国石油玉门油田分公司勘探开发研究院甘肃玉门753200

运用油藏地球化学的理论和研究方法,对酒西坳陷进行了原油族群划分、烃源岩生烃史及石油运移方向研究。酒西坳陷6个油田的原油均属于同一石油族群,又可分为成熟、高成熟和低成熟3.石油组群;酒西坳陷3.生油次凹——青南次凹、石北次凹... 详细信息

运用油藏地球化学的理论和研究方法,对酒西坳陷进行了原油族群划分、烃源岩生烃史及石油运移方向研究。酒西坳陷6个油田的原油均属于同一石油族群,又可分为成熟、高成熟和低成熟3.石油组群;酒西坳陷3.生油次凹——青南次凹、石北次凹和大红圈次凹源岩的生烃门限深度分别为4150m、3.00m和3.00m;原油物性参数变化规律及含氮化合物咔唑类参数变化表明,酒西坳陷石油运移主要方向是由西向东,即青西油田—鸭儿峡油田—老君庙油田—石油沟油田,石油沟和老君庙油田原油垂向运移为自下而上,即L层—K层。

关键词：酒西坳陷油藏地球化学青西油田原油物性生烃史石油运移生油烃源岩含氮化合物参数变化

THE RELAXING SCHEMES FOR HAMILION-JACOBI EQUATIONS

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Journal of Computational Mathematics 2001年第3期19卷 231-240页

作者： Hua-zhong Tang Hua-mu Wu (State Key Laboratory of Scientific and Engineering Computing, institute of Computational Mathematics and Scientific/Engineering Computing, Academy of Mathematics and Systems sciences, {2. Academy of sciences, beijing 100080,

Hamilton-Jacobi equation appears frequently in applications, e.g., in differential games and control theory, and is closely related to hyperbolic conservation laws[3. 4, 12.. This is helpful in the design of difference approximations for Hamilton-Jacobi equation and hyperbolic conservation laws. In this paper we present the relaxing system for HamiltonJacobi equations in arbitrary space dimensions, and high resolution relaxing schemes for Hamilton-Jacobi equation, based on using the local relaxation approximation. The schemes are numerically tested on a variety of 1D and 2. problems, including a problem related to optimal control problem. High-order accuracy in smooth regions, good resolution of discontinuities, and convergence to viscosity solutions are observed.

关键词： The relaxing scheme The relaxing systems Hamilton-Jacobi equation Hyperbolic conservation laws.

低温时效处理对铁磁形状记忆合金Mn_2.iGa的结构、相变和磁性能的影响

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物理学报 2011年第7期60卷 692-699页

作者：宋瑞宁李祥朱伟刘恩克李贵江蔡金芳王文洪吴光恒中国科学院物理研究所磁学国家重点实验室北京100190 北京理工大学材料科学与工程学院北京100081 北京理工大学理学院北京100081

对在较低温度范围的时效处理铁磁形状记忆合金Mn2.iGa的结构、相变和磁性进行了研究.研究发现,母相基体析出了细小的析出相,引起了晶格扭曲和畸变,导致了系统内产生了很大的内应力.在其浓度超过晶格的容忍度之后,提升了体系的马氏体相... 详细信息

对在较低温度范围的时效处理铁磁形状记忆合金Mn2.iGa的结构、相变和磁性进行了研究.研究发现,母相基体析出了细小的析出相,引起了晶格扭曲和畸变,导致了系统内产生了很大的内应力.在其浓度超过晶格的容忍度之后,提升了体系的马氏体相变温度,使母相在时效温度下转变成马氏体相,并在其中测量到高达900Oe的矫顽力.由于这种马氏体相的逆相变温度大幅提高,外推获得其居里温度在53.K附近.细小析出相的粗化使内应力消失,样品又回到母相状态.观察到细小析出相粗化的两个阈值温度,分别为42.0}和485K.

关键词：铁磁形状记忆合金 Mn2.iGa 时效处理内应力

REACTION OF HETEROCYCLIC KETENE AMINALS WITH DICHLOROCARBENE

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chinese Chemical Letters 1995年第1期6卷 5-8页

作者： Zhi Tang HUANG Jian Chao WANG and Li Ben WANG institute of Chemistry, Academia Sinica. beijing, 100080.Absrtact: Heterocyclic ketene aminals 1 or 2.react with dichlorocarbene to give the formyl substituted heterocylic ketene aminals {2.or 4through the ca Acad Sinica Inst Chem Beijing 100080 Peoples R China

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Reproductive characteristics of the exotic Carassius auratus in the shoals of the middle reaches of Yarlung Zangbo River in Tibet,China

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Reproductive characteristics of the exotic Carassius auratus...

ISOVALEROYL OXOKADSURANE,A NOVEL DIBENZOCYCLOOCTADIENE LIGNAN POSSESSING A SPIROBENZOPURANOID SKELETON

中国鱼类学会2.08年学术研讨会

作者： Feng Chen~(1,2.,Yifeng Chen~1 (1.institute of Hydrobiology,chinese Academy of {2.,Wuhan 43.072.China 2.The Graduate School of chinese Academy of {2.,beijing 10003.,China)

＜正＞Yarlung Zangbo River is the highest river in the *** fish fauna is very endemic and *** during recent decades,it is disturbed by exotic fishes,in which Carassius auratus has the most amount and spreads most *** paper studied the reproductive characteristics of exotic ***.3.7 specimens were collected,the female/male sex ratio was

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chinese Chemical Letters 1990年第1期1卷 37-38页

作者： Lian Niang LI Xiang Jun QI Cun Heng HE and Qi Tai ZHENG institute of Materia Medica,chinese Academy of Medical {2.,{3. 100050,China

Isovaleroyl oxokadsurane,a novel dibenzocyclooctadiene lignan pos- sessing a spirobenzofuranoid skeleton was isolated from the stems of Kadsura *** structure and relative configuration were determined by X-ray diffrac... 详细信息

关键词： ISOVALEROYL OXOKADSURANE A NOVEL DIBENZOCYCLOOCTADIENE LIGNAN POSSESSING A SPIROBENZOPURANOID SKELETON

Identification and functional analysis of a CDE/CHR element in the POLD1 promoter

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Science China(Life sciences) 2009年第6期52卷 551-559页

作者： SONG NanMeng1,ZHU XiaoYu1,2.SHI Lei1,AN Jing1,WU YanWei1 & SANG JianLi1 1 Key Laboratory of Cell Proliferation and Regulation of Ministry of Education,beijing Normal University,beijing 100875,China 2.State Key Laboratory for Infectious Disease Prevention and Control,{2. for Communicable Disease Control and Prevention,{3. Center for Disease Control and Prevention,beijing 102.06,China 1. Key Laboratory of Cell Proliferation and Regulation of Ministry of Education Beijing Normal University Beijing 100875 China 2. State Key Laboratory for Infectious Disease Prevention and Control Institute for Communicable Disease Control and Prevention Chinese Center for Disease Control and Prevention Beijing 102206 China

DNA polymerase delta is encoded by the POLD1 gene,the transcription of which is strictly cell ***,the means by which POLD1 transcription is regulated by the cell cycle mechanism is currently *** discovered a novel element in the POLD1 promoter known as a CDE(cell cycle-dependent element)/CHR(cell cycle gene homology region) element.A series of luciferase reporter constructs containing various POLD1 promoter mutations were used to investigate the role of the CDE/CHR element in POLD1 *** the CDE/CHR element was mutated,the promoter activity was up-regulated,and the cell-cycle related factors E2.1 and p2. stopped regulating the ***,cell cycle-dependent changes in the promoter activity required the integrative CDE/CHR *** mobility shift assay(EMSA) revealed the presence of at least three types of DNA/protein complexes binding to the CDE/CHR *** findings provide strong evidence that the CDE/CHR-like sequence is an active functional element in the POLD1 promoter,which is important for the cell cycle regulation of the POLD1 gene.

关键词： POLD1 gene promoter CDE/CHR element site mutant