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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 applied {2., chinese academy of sciences, shanghai 2.1800, china 2.Graduate School of chinese academy of sciences, Beijing 100049, china 1. Laboratory of Nano-biology and Medicine Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China 2. Graduate School of chinese academy of sciences Beijing 100049 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

A pulse radiolysis study on electron affinity of piperonal

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Science china Chemistry 2005年第5期48卷 476-480页

作者： MA Jianhua1, LIN Weizhen2. WANG Wenfeng2.& YAO Side2.1. College of Biology Engineering, Jimei University, Xiamen 36102., china 2. shanghai Institute of {2. physics, chinese academy of sciences, shanghai 2.1800, china 1. College of Biology Engineering Jimei University 361021 Xiamen China 2. shanghai Institute of applied {2. Chinese Academy of Sciences 201800 Shanghai China

The piperonal electron affinity was studied using pulse radiolysis technique. The electron transfer reaction process between piperonal and anthraquinone-2.sulfate was observed in the pH 7 phosphoric acid salt buffer. The transient absorption spectra of electron transfer re-action between piperonal and anthraquinone-2.sulfate were obtained, and the initial proof of the electron transfer between electron donor and acceptor was provided directly. The one-electron reduction potential of piperonal was determined to be ?0.457 V.

关键词： piperonal, pulse radiolysis, one-electron reduction potential.

Boundary element-free method for elastodynamics

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Science china(physics,Mechanics & Astronomy) 2005年第6期48卷 641-657页

作者： CHENG Yumin1 & PENG Miaojuan2.1. shanghai Institute of applied Mathematics and Mechanics, shanghai University, shanghai 2.0072. china 2. Department of Civil Engineering, shanghai University, shanghai 2.0072. china 1. shanghai Institute of applied Mathematics and Mechanics Shanghai University 200072 Shanghai China 2. Department of Civil Engineering Shanghai University 200072 Shanghai China

The moving least-square approximation is discussed first. Sometimes the method can form an ill-conditioned equation system, and thus the solution cannot be obtained correctly. A Hilbert space is presented on which an orthogonal function system mixed a weight function is defined. Next the improved moving least-square approximation is discussed in detail. The improved method has higher computational efficiency and precision than the old method, and cannot form an ill-conditioned equation system. A boundary element-free method (BEFM) for elastodynamics problems is presented by combining the boundary integral equation method for elastodynamics and the improved moving least-square approximation. The boundary element-free method is a meshless method of boundary integral equation and is a direct numerical method compared with others, in which the basic unknowns are the real solutions of the nodal variables and the boundary conditions can be applied easily. The boundary element-free method has a higher computational efficiency and precision. In addition, the numerical procedure of the boundary element-free method for elastodynamics problems is presented in this paper. Finally, some numerical examples are given.

关键词： moving least-square approximation, improved moving least-square approximation, elastodynamics, boundary integral equation, meshless method, boundary element-free method, Fourier eigen transform.

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 applied {2., the chinese academy of sciences, shanghai 2.1800) shanghai Institute of applied {2. 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

Single crystal β-Ga_2._3: Cr grown by floating zone technique and its optical properties

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Science china(Technological sciences) 2007年第1期50卷 51-56页

作者： ZHANG JunGang1, 2. LI Bin3, XIA ChangTai1, XU Jun1, DENG Qun4, XU XiaoDong1, WU Feng1, XU WuSheng4, SHI HongSheng4, PEI GuangQing1, 2.& WU YongQing1,2.1 shanghai Institute of Optics and Fine Mechanics, chinese academy of sciences,{2., china 2.Graduate School of the chinese academy of sciences, Beijing 100039, china 3 shanghai Institute of applied physics, chinese academy of sciences,{2., china 4 GE ({12.) Research and Development Center Co. Ltd., shanghai 2.12.3, china 1. shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China 2. Graduate School of the chinese academy of sciences Beijing 100039 China 3. shanghai Institute of applied {2. Chinese Academy of Sciences Shanghai 201800 China 4. GE (china) Research and Development Center Co. Ltd. Shanghai 201203 China

β-Ga2.3: Cr single crystals were grown by floating zone technique. Absorption spectra and fluorescence spectra were measured at room temperature. The values of field splitting parameter Dq and Racah parameter B were obtained by the peak values of absorption spectra. The value 10Dq/B=2..14 manifests that in β-Ga2.3 crystals Cr3+ ions are influenced by low energy crystal field. After high temperature annealing in air, the Cr3+ intrinsic emission was enhanced and the green lumines-cence disappeared. The strong and broad 691 nm emission was obtained at 42. nm excitation due to the electron transition occurred from 4T2.to 4A2. The studies manifest that the β-Ga2.3 crystals have the potential application for tunable laser.

关键词： β-Ga2.3: Cr single crystals floating zone technique tunable laser spectrum.

Organic Solvents Mediate Self-assembly of GAV-9 Peptide on Mica Surface

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Acta Biochimica et Biophysica Sinica 2007年第4期39卷 285-289页

作者： Hai LI~(1,3) Feng ZHANG~1 Yi ZHANG~1* Jianhua HE~1 Jun HU~(1,2. 1 shanghai Institute of applied {2.,chinese academy of sciences,shanghai 2.1800,china 2.Bio-X Life sciences Research Center.College of Life Science and Biotechnology,shanghai Jiaotong University,shanghai 2.0030,china 3 Graduate School of the chinese academy of sciences,Beijing 100049,china shanghai Institute of applied {2. Chinese Academy of SciencesShanghai 201800 China Graduate School of the chinese academy of sciencesBeijing 100049 China Bio-X Life sciences Research Center College of Life Science and Biotechnology Shanghai Jiaotong UniversityShanghai 200030 China

Self-assembly of peptides into fibrils and other morphologies has attracted much attention inmany fields,especially in nanofabrication,pathology and *** this paper,self-assembly of GAV-9peptide in organic solvents,ethanol and acetone,was investigated using atomic force microscopy(AFM)and attenuated total reflectance-Fourier transform infrared spectroscopy(ATR-FTIR).The results indicatedthat GAV-9 self-assembled into various nanostructures in both solvents after deposited and evaporated *** with β-sheet conformation were observed in both solvents when the peptide concentrationwas higher than 2.0 μ***,ordered fibrils with β-sheet conformation were formed in ethanol,butnot in acetone,with a peptide concentration ranging from 7 μM to 2. μ*** attribute the formation ofvarious nanostructures to the different physicochemical properties of the polar organic solvents on the self-assembly of GAV-9 peptide.

关键词： self-assembly GAV-9 peptide organic solvents ATR-FTIR AFM

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 applied {2. 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 applied {2.,chinese academy of sciences,shanghai 2.1800,china 1. Radiopharmaceutical Centre Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China

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

A complex variable meshless method for fracture problems

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Science china(physics,Mechanics & Astronomy) 2006年第1期49卷 46-59页

作者： CHENG Yumin1 & LI Jiuhong2.1. shanghai Institute of applied Mathematics and Mechanics, shanghai University, shanghai 2.0072. china 2. Department of Building Engineering, Xi’an University of Technology, Xi’an 710048, china shanghai Institute of applied Mathematics Mechanics Shanghai University Shanghai 200072 China Department of Building Engineering Xi’an University of Technology Xi’an 710048 China

Based on the moving least-square (MLS) approximation, the complex variable moving least-square approximation (CVMLS) is discussed in this paper. The complex variable moving least-square approximation cannot form ill-conditioned equations, and has greater precision and computational efficiency. Using the analytical solution near the tip of a crack, the trial functions in the complex variable moving least-square approxi- mation are extended, and the corresponding approximation function is obtained. And from the minimum potential energy principle, a complex variable meshless method for fracture problems is presented, and the formulae of the complex variable meshless method are obtained. The complex variable meshless method in this paper has greater precision and computational efficiency than the conventional meshless method. Some examples are given.

关键词： moving least-square approximation, complex variable moving least-square approximation, meshless method, complex variable meshless method, fracture.