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Study on the atmospheric photochemical reaction of CF_3 radicals using ultraviolet photoelectron and photoionization mass spectrometer

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Science china Chemistry 2008年第4期51卷 316-321页

作者： YAO Li1,2, DU Lin1,2, YIN Shi1,2 & GE MaoFa1 1 beijing National laboratory for Molecular sciences (BNLMS), state key laboratory for Structural Chemistry of Unstable and Stable Species, institute of Chemistry, chinese academy of sciences, beijing 100080, china 2 Graduate University of chinese academy of sciences, beijing 100080, china 1. beijing National laboratory for Molecular sciences (BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China 2. Graduate University of chinese academy of sciences Beijing 100080 China

A study of the atmospheric photochemical reaction of CF3 radical with CO and O2 was performed by using a homemade ultraviolet photoelectron spectrometer-photoionization mass spectrometer (PES- PIMS). The electronic structures and mechanism of ionization and dissociation of CF3OC(O)OOC(O)- OCF3 were investigated. It was indicated that the two bands on the photoelectron spectrum of CF3OC(O)OOC(O)OCF3 are the result of ionization of an electron from a lone pair of oxygen and a fluo- rine lone pair of CF3 group. The outermost electrons reside in the oxygen lone pair. The experimental and theoretical first vertical ionization energy is 13.21 and 13.178 eV, respectively, with the PES and OVGF method. They are in good agreement. The photo ionization and dissociation processes were discussed with the help of theoretical calculations and PES-PIMS experiment. After ionization, the parent ions prefer the dissociation of the C-O bond and giving the fragments CF3OCO+ and CF3+. It demonstrated that the ultraviolet photoelectron and photoionization mass spectrometer could be ap- plied widely in the study of atmospheric photochemical reaction.

关键词： photochemical reaction CF3 radical ultraviolet photoelectron and photoionization mass spectroscopy transient species

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Role of plasminogen activators and inhibitors in reproduction

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chinese Science Bulletin 1999年第8期44卷 673-685页

作者： LIU Yixunstate key laboratory of Reproductive Biology, institute of Zoology , chinese academy of sciences , beijing 100080, china state key laboratory of Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing China

The recent progress in the studies on the role of local and directed fibrinolysis controlled by plasminogen activators (PAs) and regulated by their inhibitors (PAIs) in reproduction is summarized. Hormone-induced coordinated expression of tissue type PA (tPA) and PAI type-1 (PAI-1) in the ovary is involved in the processes of ovulation and luteal regression; increases in urokinase type PA (uPA) and PAI-1 activity in the early stage of luteinized follicles may be responsible for ovarian tissue remodeling and angiogenesis; the PA system has been found to play an important role in spermatogenesis in testis and modulation of sperm maturation in epididymis. PA and matrix matalloproteanase (MMP) and their respective inhibitors have also been identified in trophoblast and uterus. The targeted proteolytic activity generated by the two systems may play an essential role in the processes of the cyclic uterine angiogenesis, implantation and pla-centation as well as parturition.

关键词： plasminogen activator and inhibitor follicle rupture luteolysis angiogenesis spermatogenesis placentation.

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A new transient stability margin based on dynamic security region and its applications

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Science china(Technological sciences) 2008年第6期51卷 751-760页

作者： XUE AnCheng1, 2 & MEI ShengWei1 1 state key Lab of Power Systems, Department of Electrical Engineering, Tsinghua University, beijing 100084, china 2 key Lab of Systems and Control, institute of Systems Science, chinese academy of sciences, beijing 100190, china 1. state key Lab of Power Systems Department of Electrical Engineering Tsinghua University Beijing 100084 China 2. key Lab of Systems and Control Institute of Systems Science Chinese Academy of Sciences Beijing 100190 China

A new transient stability margin is proposed based on a new expression of dynamic security region (DSR) which is developed from the existing expression of DSR. Applications of the DSR based transient stability margin to contingency ranking and screening are discussed. Simulations in the 10-machine 39-bus New England system are performed to show the effectiveness of the proposed DSR based tran-sient stability margin.

关键词： dynamic security region (DSR) transient stability margin contingency screening

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Electron structure and substituent effects in o-,m-,p-IC_6H_4OCH_3 iodoanisoles

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Science china Chemistry 2009年第11期52卷 1932-1937页

作者： TONG ShengRui,WANG WeiGang,MA ChunPing,GE MaoFa & WANG DianXun beijing National laboratory for Molecular sciences(BNLMS),state key laboratory for Structural Chemistry of Unstable and Stable Species,institute of Chemistry,chinese academy of sciences,beijing 100190,china 1. beijing National laboratory for Molecular sciences (BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China

The electronic structures and substituent effects in o-,m-,and p-iodoanisoles have been investigated by ultraviolet photoelectron spectroscopy(UPS).The observed UPS bands were analyzed by combining empirical arguments and theoretical *** to the electron-donating nature of both iodoand methoxy substituents,the first ionization potentials of the three iodoanisoles are lower than those of iodobenzene and *** presence of the two substituents in iodoanisoles leads to an electronrich structure,which might contribute to the observed high reactivity of iodoanisoles in a number of organic reactions.

关键词： electronic structures substituent effects ultraviolet photoelectron spectroscopy reactivity

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Properties of mouse retinal ganglion cell dendritic growth during postnatal development

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Science china(Life sciences) 2010年第6期53卷 669-676页

作者： YANG XiuLan,SHI XiangMing & HE ShiGang state key laboratory of Brain and Cognitive sciences,institute of Biophysics,chinese academy of sciences,beijing 100101,china 1. state key laboratory of Brain and Cognitive sciences Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China

The property of dendritic growth dynamics during development is a subject of intense ***,we investigated the dendritic motility of retinal ganglion cells (RGCs) during different developmental stages,using ex vivo mouse retina explant culture,Semliki Forest Virus transfection and time-lapse *** results illustrated that during development,the dendritic motility underwent a change from rapid growth to a relatively stable state,i.e.,at P0 (day of birth),RGC dendrites were in a highly active state,whereas at postnatal 13 (P13) they were more stable,and at P3 and P8,the RGCs were in an intermediate *** any given developmental stage,RGCs of different types displayed the same dendritic growth rate and *** the mouse is the most popular mammalian model for genetic manipulation,this study provided a methodological foundation for further exploring the regulatory mechanisms of dendritic development.

关键词： retinal ganglion cells dendritic development time-lapse observation

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On the placement of actuators and sensors for flexible structures with closely spaced modes

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Science china(Technological sciences) 2010年第7期53卷 1973-1982页

作者： LIU XiaoXiang1,2 & HU Jun1,2 1 beijing institute of Control Engineering, beijing 100190, china 2 state key laboratory of Science and Technology on Space Intelligent Control, beijing 100190, china 1. beijing institute of Control Engineering Beijing 100190 China2. State Key Laboratory of Science and Technology on Space Intelligent Control Beijing 100190 China

This paper analyzed the fundamental limitations of previous work and developed a new method to optimally locate actuators and sensors for structures with close modes. Optimization criteria were defined based on the distinguishing modal controllability and observability measures of close modes. An appropriate genetic algorism was adopted as the optimization algorism. Solving the high order Lyapunov functions was avoided by means of the closed-form expressions for controllability and observability Grammians. Since structure with widely separated natural frequencies is approximately balanced, computational efficiency was improved by grouping close modes together and dealing with the resulting subsystems independently. Finally, the effectiveness and optimality of the novel placement scheme were verified on a model structure with close modes.

关键词： close modes controllability/observability sensor/actuator optimization criterion optimization algorithm

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Preparation and Characterization of Co_(0.3)Cr_(0.7)O_x Particles Using for Thermal Radiation Coating

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稀有金属材料与工程 2012年第S1期41卷 100-103页

作者： Luo Lijie1,2,Huang Chuanbing1,Zhu Yongping1,Zhang Weigang1 1 state key laboratory of Multi-phase Complex Systems,institute of Process Engineering,chinese academy of sciences,beijing 100190,china 2 Graduate University of chinese academy of sciences,beijing 100049,china chinese Acad Sci Inst Proc Engn State Key Lab Multiphase Complex Syst Beijing 100190 Peoples R China chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

Novel Co0.3Cr0.7Ox(x=2-3)particles with spinel structure were synthesized via precipitation method through the reactions among CoSO4,Cr(NO3)3 and NaOH solutions,followed by spray-drying and sintering at 1200 ℃for 4h in the *** particles were characterized by X-ray diffraction(XRD)and scanning electron microscopy(SEM).The XRD results revealed that the particles are composed of Co0.3Cr0.7Ox phase without the presence of other *** SEM observation showed that the particles are in the shape of sphere with well *** radiation test indicated that the total infrared normal emissivity of the coating made of Co0.3Cr0.7Ox can be up to 0.92 at 800℃.And the normal emissivities of the prepared Co0.3Cr0.7Ox particles are always slightly larger than those of CoCr2O4 particles prepared by solid-state reaction method in the test temperature range of 50-300℃.The relatively high thermal emissivity of Co0.3Cr0.7Ox is assumed to be mainly attributed to the spinel *** results indicated that Co0.3Cr0.7Ox particles are a good thermal radiation material,which can be used as infrared radiation layer in thermal protection system.

关键词： Co0.3Cr0.7Ox particles preparation precipitation thermal radiation coating

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Geometry of Broad Line Regions of Active Galactic Nuclei

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chinese Journal of Astronomy and Astrophysics 2008年第1期8卷 50-62页

作者： Xiao-Rong Lü1 key laboratory for Particle Astrophysics, institute of High Energy Physics, chinese academy of sciences, beijing 100049 2 Graduate School of chinese academy of sciences, beijing 100049 key laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 and Graduate School of chinese academy of sciences Beijing 100049

It has long remained an open question as to the geometry of the broad line region （BLR） in active galactic nuclei （AGNs）. The reverberation mapping technique which measures the response of the broad emission lines to the ionizing continuum, when combined with multiwavelength continuum fitted by sophisticated accretion disks, provides a way of probing the BLR geometry. We analyze a sample of 35 AGNs, which have been monitored by the reverberation mapping campaign. In view of energy budget, the reverberation-based BH masses are found to be in agreement with those obtained by accretion disk models in two thirds of the present sample while the reverberation mapping methods underestimate the BH masses in about one third of objects, as also suggested by CoUin et al. in a recent work. We point out that there are obviously two kinds of BLR geometry, which are strongly dependent on the Eddington ratio, and separated by the value LBol/LEdd - 0.1. These results prefer a scenario of the disk and wind configuration of the BLR and identify the Eddington ratio as the physical driver regulating the wind in the BLR.

关键词： accretion, accretion disks - galaxies active - galaxies Seyfert - quasars general

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Follicular growth,differentiation and atresia

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chinese Science Bulletin 2003年第17期48卷 1786-1790页

作者： JIN Xuan & LIU Yixun state key laboratory of Reproductive Biololgy, institute of Zoology, chinese academy of sciences, beijing 100080, china state key laboratory of Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing 100080 China

Only limited numbers of primordial follicles in mammalian ovary grow and differentiate to reach the stage of dominate follicles and ovulate. 99% of the follicles in the ovary undergo atresia at various stages of development. Regulation of follicular growth, development and atresia is a complex process and involves interactions between endocrine factors and intraovarian regulators. This review summa-rized:ⅰ) FSH may not be a survival factor in regulating slow-growing preantral follicles. Some locally produced growth factors, activin and orphan receptors might play a more important role at this stage. ⅱ) Estrogen, activin/ inhibin and follistatin coordinate with FSH to regulate and control follicle differentiation. ⅲ) There are two types of follicular atresia induced by apoptosis which originates from GC or oocyte, respectively. Early translation of tPA mRNA into tPA protein in oocyte may be associated with oocyte apoptosis.

关键词：哺乳动物原始卵泡卵泡生长粒状细胞细胞分化

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ON THE EXPLICIT COMPACT SCHEMES II: EXTENSION OF THE STCE/CE METHOD ON NONSTAGGERED GRIDS ON THE EXPLICIT COMPACT SCHEMES II: EXTENSION OF THE STCE/CE METHOD ON NONSTAGGERED GRIDS

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Journal of Computational Mathematics 2000年第5期18卷 467-480页

作者： Hua-zhong Tang , Hua-mu Wu (state key laboratory of Scientific and Engineering Computing, institute of Computational Mathematics, chinese academy of sciences, beijing 100080, china) 中科院计算数学所科学与工程计算国家重点实验室北京 100080

This paper continues to construct and study the explicit compact (EC) schemes for conservation laws. First, we axtend STCE/SE method on non-staggered grid, which has same well resolution as one in [1], and just requires half of the computational works. Then, we consider some constructions of the EC schemes for two-dimensional conservation laws, and some 1D and 2D numerical experiments are also given.

关键词： Conservation laws Compact scheme Shock-Capturing method Euler equations.

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