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Chinese Physics Letters 2001年第8期18卷 1033-1036页

作者： FANG De-Qing SHEN Wen-Qing FENG Jun CAI Xiang-Zhou MA Yu-Gang ZHANG Hu-Yong ZHONG Chen ZHAN Wen-Long GUO Zhong-Yan XIAO Guo-Qing WANG Jian-Song WANG Jin-Chuan LI Jia-Xing WANG Meng WANG Jian-Feng NING Zhen-Jiang WANG Quan-Jin CHEN Zhi-Qiang Shanghai Institute of Nuclear research Chinese Academy of SciencesShanghai 201800 Institute of Modern Physics Chinese Academy of SciencesLanzhuo 730000 Department of Physics Ningbo UniversityNingbo 315211

Measurements of total reaction cross sections(σR)for some proton-rich nuclei(N=11-15 isotones)on carbon target at intermediate energies have been performed on the Radioactive Ion Beam Line of the Heavy Ion research Facility in Lanzhou.A large enhancement ofσR for ^(27)P has been observed than for its *** for a proton halo in ^(27)P has been revealed in the Glauber analysis of the total reaction cross sections in terms of the difference factor d.

关键词： Proton neighbor Observation

Self-assembly of two- dimensional DNA crystals

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Chinese Science Bulletin 2004年第9期49卷 879-882页

作者： SONGCheng CHENYaqing WEIShuai YOUXiaozeng XIAOShoujun stateKeyLaboratoryofCoordinationChemistry CollegeofChemistryandChemicalEngineeringNanjingUniversityNanjing210093China

Self-assembly of synthetic oligonucleotides into two-dimensional lattices presents a 慴ottom-up?approach to the fabrication of devices on nanometer scale. We report the design and observation of two-dimensional crystalline forms of DNAs that are composed of twenty-one plane oligonucleo-tides and one phosphate-modified oligonucleotide. These synthetic sequences are designed to self-assemble into four double-crossover (DX) DNA tiles. The 憇ticky ends?of these tiles that associate according to WatsonCrick抯 base pairing are programmed to build up specific periodic patterns upto tens of microns. The patterned crystals are visualized by the transmission electron microscopy.

关键词：自组装二维DNA晶体寡核苷酸 5'-磷酸盐 DNA砖

Cloning and Characterization of a Novel Gene SRG-L Expressed in Late Stages of Mouse Spermatogenic Cells

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Acta Biochimica et Biophysica Sinica 2004年第5期36卷 315-322页

作者： Rui GUO, Peng-Peng MA, Jing MA, Ye-Hua GE, She-Pu XUE, and Dai-Shu HAN*Department of Cell Biology, Institute of basic Medical Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College,Beijing 100005, china Department of Cell Biology Institute of Basic Medical Sciences Chinese Academy of Medical Sciences & Peking Union Medical College

A cDNA expressed specifically in late stages of mouse spermatogenic cells during spermato- genesis was cloned by using overlapping RT-PCR and RACE. The cDNA contained an open reading frame (ORF) of 2625 base pairs that encoded an 874 amino acids protein. Comparison analysis of amino acid sequence showed 91% and 80% identity to a rat homologue XP-226242 and a monkey homologue BAB63115 respectively. The expression of the mRNA was only observed in pachytene spermatocytes, round, and elongating spermatids. We named this gene as SRG-L (spermatogenesis related gene expressed in the late stages of spermatogenic cells, GenBank accession No. AY352586). The tissue-specific analysis showed that the SRG-L was highly expressed in spleen and testis. The results suggested that SRG-L might play special roles during spermatogenesis, particularly related to meiosis and spermiogenesis. Analysis of the amino acid sequence showed there was a coiled-coil region near the N-terminal region and rich phosphorylation sites, suggesting SRG-L might function as a transmembrane protein mediating signal transduction. This study also demonstrated that gene cloning by RT-PCR was applicable and convenient when its homologous gene was known.

关键词： spermatogenesis RT-PCR RACE gene cloning

Fabrication of MgB2 superconducting films by different methods

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Progress in Natural Science:Materials International 2006年第2期16卷 175-177页

作者： WANG Shufang, ZHOU Yueliang, ZHU Yabin, CHEN Zhenghao, LU Huibin and YANG Guozhen ( Physics & Technology College, Hebei University, Baoding 071002, china Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, china) [a]Physics & Technology College Hebei University Baoding China [b]Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing China

MgB2 superconducting films have been successfully fabricated on single crystal MgO(111) and c-AL2O3 substrates by different methods. The film deposited by pulsed laser deposition is c-axis oriented with zero resistance transition temperature of 38.4 K, while the other two films fabricated by chemical vapor deposition and electrophoresis are c-axis textured with the zero resistance transition temperature of 38 K and 39 K, respectively. Magnetization hysteresis measurements yield critical current density Jc of 107 A/cm2 at 15 K in zero field for the thin film and of 105 A/cm2 for the thick film. For the thin film deposited by chemical vapor deposition, the microwave surface resistance at 10 K is found to be as low as 100μΩ, which is comparable with that of a high-quality high-temperature superconducting thin film of YBCO.

关键词： MgB2 superconducting films chemical vapor deposition pulsed laser deposition electrophoresis.

Eliminate indeterminacies of independent component analysis for chemometrics

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Progress in Natural Science:Materials International 2008年第8期18卷 1009-1014页

作者： Zhixiang Yao a,b, Kai Zhang c,*, Huanbin Liu b, Hui Su a a Department of Biological and Chemical Engineering, Guangxi University of Technology, Liuzhou 545006, china b state Key Laboratory of Pulp and Paper-making Engineering, South china University of Technology, Guangzhou 510640, china c state Key Laboratory of Heavy Oil Processing, china University of Petroleum, Beijing 102249, china Department of Biological and Chemical Engineering Guangxi University of Technology Liuzhou 545006 China state Key Laboratory of Pulp and Paper-making Engineering South China University of Technology Guangzhou 510640 China state Key Laboratory of Heavy Oil Processing China University of Petroleum Beijing 102249 China

An improved method has been proposed to eliminate the indeterminacies of independent component analysis (ICA) for chemometrics. Following the arrangement of principal components analysis (PCA), the ICA mixing matrix is selected as signal content indexes, and ICA output are sorted and directed. After many times reputations, independent components (ICs) are paired according to the maximum correlation coefficient, and then the mean values of each IC substitutes the original ICs. This indicates that the ICA indeterminacies are eliminated. A simulation example is tested to validate this improvement. Finally, a set of experimental LC-MS data is processed without any prior knowledge or specific limitation and the results show that the improved ICA can directly separate the mixed signals in chemometrics, and it is simpler and more reasonable than the simple to use interactive self-modeling mixture analysis (SIMPLISMA).

关键词： Independent component analysis Indeterminacy in ICA Chemometrics

Transmission ratio (T_n) in the radian direction normal to joints in 2-D compressional wave propagation in rock masses

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Journal of University of Science and Technology Beijing 2006年第3期13卷 199-206页

作者： Weidong Lei Jun Teng Ashraf Mohamed Hefny Jian Zhao Department of Urban and Civil Engineering Shenzhen Graduate School Harbin Institute of Technology Shenzhen 518055 China School of Civil and Environmental Engineering Nanyang Technological University Singapore 639798 Singapore Ecole Polytechnique Federale de Lausanne （EPFL） Rock Mechanics Laboratory Lausanne CH-1015 Switzerland College of Architecture and Civil Engineering China University of Mining and Technology Xuzhou 221008 China

The transmission ratio along the radian direction normal to the joints was studied in the Universal Distinct Element Code （UDEC）. The variation of the transmission ratio with the ratio of joint spacing to wavelength was generalized into a general curve, which was determined by two critical points. The relationship between the two critical points and the affecting factors, quantity of joints and the normalized normal stiffness of joints, were obtained. A prediction model of the transmission ratio in the radian direction normal to the joints was proposed. The proposed model was applied to a field explosion test. The estimated values of the peak particle velocity from the prediction model were compared with the field records. The comparisons showed that the prediction model of the transmission ratio in the direction normal to the joints in the process of 2-D compressional wave propagation through multiple parallel joints is reliable.

关键词： 2-D compressional wave wave propagation transmission ratio field explosion test

Age-hardening characteristic of an Al-Zn-Mg-Cu alloy produced by spray deposition

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Rare Metals 2007年第2期26卷 163-168页

作者： WANG Feng XIONG Baiqing ZHANG Yongan ZHU Baohong LIU Hongwei ZHANG Zhihui WANG Zixing state Key Laboratory for Fabrication and Processing of Nonferrous Metals Beijing General Research Institute for Nonferrous Metals Beijing 100088 China

Al-10.8Zn-2.8Mg-1.9Cu alloy was synthesized by spray atomization and deposition technique. GP zones and age-hardening process in the alloy were investigated using high-resolution electron microscopy （HREM）, selected area diffraction （SAD）, and differential scanning calorimetry （DSC） analysis. The results indicated that spray deposition process accelerated the aging kinetics of the alloy at an aging temperature of 120℃, thereby reducing the peak aging time to 16 h. GPⅠ and GPⅡ are the two types of zones that are major precipitates for the alloy under peak-aged condition. The precipitation sequence for the alloy is also discussed.

关键词： aluminium alloy precipitation GP zone spray deposition

Non-integrating lentiviral vectors based on the minimal S/MAR sequence retain transgene expression in dividing cells

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Science china(Life Sciences) 2016年第10期59卷 1024-1033页

作者： Zhen Xu Feng Chen Lingling Zhang Jing Lu Peng Xu Guang Liu Xuemin Xie Wenli Mu Yajun Wang Depei Liu state Key Laboratory of Medical Molecular Biology Department of Biochemistry and Molecular Biology Institute of Basic Medical SciencesChinese Academy of Medical Sciences and Peking Union Medical College

Safe and efficient gene transfer systems are the basis of gene therapy applications. Non-integrating lentiviral(NIL) vectors are among the most promising candidates for gene transfer tools, because they exhibit high transfer efficiency in both dividing and non-dividing cells and do not present a risk of insertional mutagenesis. However, non-integrating lentiviral vectors cannot introduce stable exogenous gene expression to dividing cells, thereby limiting their application. Here, we report the design of a non-integrating lentiviral vector that contains the minimal scaffold/matrix attachment region(S/MAR) sequence(SNIL), and this SNIL vector is able to retain episomal transgene expression in dividing cells. Using SNIL vectors, we detected the expression of the eGFP gene for 61 days in SNIL-transduced stable CHO cells, either with selection or not. In the NIL group without the S/MAR sequence, however, the transduced cells died under selection for the transient expression of NIL vectors. Furthermore,Southern blot assays demonstrated that the SNIL vectors were retained extrachromosomally in the CHO cells. In conclusion,the minimal S/MAR sequence retained the non-integrating lentiviral vectors in dividing cells, which indicates that SNIL vectors have the potential for use as a gene transfer tool.

关键词： gene transfer non-integrating lentivirus scaffold/matrix attachment region (S/MAR) episomal vectors

A new OLED SPICE model for pixel circuit simulation in OLED-on-silicon microdisplay design

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Journal of Semiconductors 2012年第7期33卷 102-107页

作者：赵博华黄苒卜建辉吕荫学王一奇马飞谢国华张振松杜寰罗家俊韩郑生赵毅 Institute of Microelectronics Chinese Academy of Sciences National Laboratory of Integrated Optoelectronics Jilin University

A new equivalent circuit model of organic-light-emitting-diode （OLED） is proposed. As the single- diode model is able to approximate OLED behavior as well as the multiple-diode model, the new model will be built based on it. In order to make sure that the experimental and simulated data are in good agreement, the constant resistor is exchanged for an exponential resistor in the new model. Compared with the measured data and the results of the other two OLED SPICE models, the simulated I-V characteristics of the new model match the measured data much better. This new model can be directly incorporated into an SPICE circuit simulator and presents good accuracy over the whole operating voltage.

关键词： OLED-on-silicon pixel circuit microdisplay SPICE model CMOS

A motion instability formation mechanism of the multi-core structure of the East china Sea Kuroshio

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Science china Earth Sciences 2003年第2期46卷 182-192页

作者：袁业立万振文张庆华 First Institute of Oceanography State Oceanic Administration

On the basis of the inductive analysis of observation and calculation results, this paper presents a motion instability formation mechanism of the multi-core structure of the East china Sea Kuroshio. This theoretical work includes presentation of the simplified model, derivation of the existence condition of the instable solution and some scaling estimation of the multi-core structure. Theoretical results are in good consistence with the observations.

关键词： East china Sea Kuroshio, multi-core structure, motion instability, scaling estimation.