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Simulation on C/A codes and analysis of GPS/pseudolite signals acquisition

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Science china(Technological sciences) 2009年第5期52卷 1459-1462页

作者： ZHANG Lei shanghai institute of Technical {2.,chinese academy of sciences,shanghai 2.0083,china shanghai institute of Technical {2. Chinese Academy of Sciences

The global positioning system(GPS) is an extremely mature technique in the navigation and position-ing ***,there are still some limits in some aspects and for some special ***-cially,the performance of GPS needs to be improved with technological *** a GPS-like ground transmitter,the pseudolite provides a new research direction to achieve high positioning ac-curacy and *** this paper,we describe the core technologies of designing and simulation on the coarse acquisition codes in constructing the pseudolite *** the GPS/pseudolite integration system,the signal PRN 36 of the pseudolite and the GPS satellites signals are acquired in the modified receiver based on the computer software *** is shown that the pseudolite technology is ideally suited to augment the GPS alone and provide greater integrity,availability,and continuity of the navi-gation positioning system,especially for indoor use.

关键词： GPS pseudolite coarse acquisition(C/A) code acquisition

Simulations for optimization of SSRF BPM

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Nuclear Science and Techniques 2003年第4期14卷 222-225页

作者： YANG Nuo, LIU Gui-Min (shanghai institute of {2. physics, the chinese academy of sciences, shanghai 2.1800) shanghai institute of {2. physics the Chinese Academy of Sciences 上海 201800

The wake field, impedance and output signal for SSRF BPM have been calculated and analyzed by us-ing the numerical simulation code of MAFIA. The narrow-band impedance of BPM arising from formation of reso-nance in its cavity like structure either is harmful to beam or limits the performance of BPM itself, and should be re-duced to tolerable levels. The calculated results show that there are three main peaks in the impedance spectrum ofthe SSRF BPM prototype, and two of which are above the limit. After lots of simulations for different shapes of theBPM button, a new structure of SSRF BPM have been found, and there is only one main peak, which is under thelimit, in the impedance spectrum. Its output signal also meets the requirement.

关键词：数值模拟耦合阻抗 BPM 上海同步加速器辐射装置 SSRF 束定位监视器 MAFIA模型

Cytotoxicity of carbon nanotubes

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Science china Chemistry 2008年第11期51卷 1021-1029页

作者： ZHU Ying1,2.& LI WenXin1 1 Laboratory of Nano-biology and Medicine, shanghai institute of {2. physics, chinese academy of sciences, shanghai 2.1800, china 2.Graduate School of chinese academy of sciences, Beijing 100049, china Laboratory of Nano-biology and Medicine Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai China Graduate School of chinese academy of sciences Beijing China

With large-scale production and application at large scale, carbon nanotubes (CNTs) may cause ad-verse response to the environment and human health. Thus, study on bio-effects and safety of CNTs has attracted great attention from scientists and governments worldwide. This report briefly summa-rizes the main results from the in vitro toxicity study of CNTs. The emphasis is placed on the descrip-tion of a variety of factors affecting CNTs cytotoxicity, including species of CNTs, impurities contained, lengths of CNTs, aspect ratios, chemical modification, and assaying methods of cytotoxicity. However, experimental information obtained thus far on CNTs' cytotoxicity is lacking in comparability, and some-times there is controversy about it. In order to assess more accurately the potential risks of CNTs to human health, we suggest that care should be taken for issues such as chemical modification and quantitative characterization of CNTs in cytotoxicity assessment. More importantly, studies on physical and chemical mechanisms of CNTs' cytotoxicity should be strengthened; assaying methods and evaluating criteria characterized by nanotoxicology should be gradually established.

关键词： carbon nanotubes (CNTs) cell bio-security

Transverse patterns and spatiotemporal instability of a photorefractive oscillator

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chinese Science Bulletin 1997年第9期42卷 724-729页

作者： ZHUANG Jun and TAN Weihan1. shanghai institute of Optics and Fine Mechanics,{2., shanghai 2.1800, china 2. shanghai University, shanghai 2.1800, china shanghai institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai China shanghai University Shanghai China

IN time realm,instability and chaos phenomena of a nonlinear optical system have been dis-cussed *** recent years,as much interest was attracted to the transverse ef-fects in nonlinear optics,the study was developed t... 详细信息

关键词： photorefractive oscillator spatiotemporal instability transverse patterns.

Experimental research on the residual magnetization of a rare-earth permanent magnet for a cryogenic undulator

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chinese physics B 2013年第7期22卷 180-182页

作者：何永周 shanghai institute of {2. physics Chinese Academy of Sciences

The magnetic properties of commercial polycrystalline Nd2.e14B （N50M,N45H,N40SH,N35EH） and Sm2.o17（XG30/2.,XG2./2.,XG2./2.） magnets at cryogenic temperatures were tested by using a comprehensive physical properties measurement system （PPMS）. The results show that the spin tilt temperature Tst of Nd2.e14B magnets is closely related to intrinsic coercivity Hci , N50M and N45H with smaller Hci show a residual magnetization jump at 2.5K and 2.5K, respectively. For Sm2.o17 magnets, in 50-300 K, with temperature decreasing, residual magnetization Mrc shows a nearly linear increase, while in 10-50 K, Mrc has little change. The research results provide a reference for cryogenic undulators and other high-precision cryogenic devices.

关键词： Nd2.e14B and Sm2.o17 spin reorientation residual magnetization intrinsic coercivity

Synthesis of O-(2.[^(18)F]fluoroethyl)-L-tyrosine and its biological evaluation in B16 melanoma-bearing mice as PET tracer for tumor imaging

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Science china Chemistry 2007年第2期50卷 276-283页

作者： WANG MingWei,YIN DuanZhi,LI ShiQiang & WANG YongXian Radiopharmaceutical Centre,shanghai institute of {2. physics,chinese academy of sciences,shanghai 2.1800,china Radiopharmaceutical Centre Shanghai Institute of Applied PhysicsChinese Academy of SciencesShanghai 201800China

O-(2.[18F]fluoroethyl) -L-tyrosine([18F]FET) ,a fluorine-18 labeled analogue of tyrosine,has been syn-thesized and biologically evaluated in tumor-bearing mice. The whole synthesis procedure is com-pleted within 50 min. The radiochemical yield is about 40%(no decay corrected) and radiochemical purity more than 97% after simplified solid phase extraction. [18F]FET shows rapid,high uptake and long retention in the tumor as well as low uptake in the brain. The ratios of tumor-to-muscle(T/M) and tumor-to-blood(T/B) of [18F]FET are similar to those of [18F]FDG,but the ratios of tumor-to-brain(T/Br) are 2.3 times higher than that of [18F]FDG. Autoradiography of [18F]FET demonstrates a remarkable accumulation in melanoma with high contrast. It appears to be a probable competitive candidate for melanoma imaging with PET.

关键词： [18F]FET [18F]FDG PET imaging melanoma autoradiography

Structural and microstructural transformations in Bi_2.r_2.a_(1-x)Y_xCu_2._(8+y) system

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chinese Science Bulletin 1997年第3期42卷 192-196页

作者： SONG Chengyu, WEN Shulin and CHE Guangcan1. shanghai institute of Ceramics,{2., shanghai 2.0050, china 2. State Key Laboratory of Supercon-ductivity, institute of physics,{2., Beijing 100080, china shanghai institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

SINCE the discovery of high-Tc superconductors, experiments have revealed that the phase diagrams of La2.xSrxCuO4 and YBa2.u3O6+x resemble each other. The antiferromagnetic phase is commonly situated in the vicinity o... 详细信息

SINCE the discovery of high-Tc superconductors, experiments have revealed that the phase diagrams of La2.xSrxCuO4 and YBa2./sub>Cu3O6+x resemble each other. The antiferromagnetic phase is commonly situated in the vicinity of the superconductive phase. In Bi-2.12.sys-

关键词： Bi2.r2.a1-xYxCu2.y substitution structural transformation.

X-ray Powder Diffraction Pattern of Bi_4(SiO_4)_3

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Journal of Materials Science & Technology 1997年第2期13卷 145-148页

作者： Hongchao LIU Changlin KUO (shanghai institute of Ceramics,{2., shanghai 2.0050, china) shanghai institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

In cooperation with figure-of-merits the Rietveld analysis can appraise both angular and intensity data of powder diffraction. In this work, X-ray diffraction pattern of Bi4(SiO4)3 was redetermined with intensity figure-of-merits, which qualify agreement between observed and calculated relative intensities. F30 is 158.90 (0.0059, 32., intensity figure of merit Rint is 8.7, I2.(17), 8.0. The values of figure-of-merits show that the data of JCPDS cards are distorted. Both the experimental and calculated peak positions and heights are listed in detail.

关键词： SiO4 X-ray Powder Diffraction Pattern of Bi4 Bi

Valence Distribution in AT_xV_(6-X)O_(11) Compounds

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Journal of Materials Science & Technology 1999年第6期15卷 551-554页

作者： Hongchao LIU and Changlin KUO(shanghai institute of Ceramics,{2., shanghai 2.0050, china) shanghai institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

The distribution of trivalent and tetravalent cations in several ATxV6-xO11 compounds was quantitatively studied by the bond valence method. In SrV6O11, the M(3) sites were mainly occupied by trivaient cations; while M(1) and M(2. sites were shared by trivalent and tetravalent cations, the relative content of tetravalent at M(1) sites was higher than at M(2. sites. During substitution process, the trivalent cations preferred to occupy M(3) sites, tetravalent ones preferred to occupy M(2. sites. The occupancy of trivalent and tetravalent cations at M sites would change with the substitution

关键词： AT X)O Valence Distribution in AT_xV Compounds