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Study on growth and properties of novel γ-LiAlO_2 substrate

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Science china(Technological sciences) 2006年第2期49卷 188-193页

作者： ZOU Jun1,2, ZHOU Shengming1, XU Jun1 & ZHANG Rong3 1. shanghai institute of Optics and Fine Mechanics, chinese academy of sciences, shanghai 201800, china 2. Graduate School of chinese academy of sciences, Beijing 100039, china 3. Laboratory of Solid State Microstructures and Department of physics, Nanjing University, Nanjing 210093, china 1. shanghai institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China 2. Graduate School of chinese academy of sciences Beijing 100039 China 3. Laboratory of Solid State Microstructures and Department of physics Nanjing University Nanjing 210093 China

Transparent γ-LiAlO2 single crystal has been grown by Temperature Gradient technique. The surface of the wafer annealed in O2-atmosphere at 1100°C for 70 h became opaque and Li-poor phase (LiAl5O8); while, that annealed in Li-rich atmosphere kept transparent and smooth. The full-width at half maximum value dropped to 30 arcsecs when the wafer was annealed in Li-rich atmosphere. That annealed in O2-atmosphere increased to 78 arcsec. Compared with absorption spectra, we can conclude that the 196 nm absorption peak was caused by Li vacancies and the 736 nm peak was caused by O vacancies.

关键词： γ-LiAlO2 crystal, scanning electron micrograph (SEM), absorption spectra.

Synthesis of per(poly)fluoroalkyl substituted alkenes and alkynes——Utilizing potassium fluoride supported on alumina as a denydrohalogenating agent

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chinese Journal of Chemistry 1994年第5期12卷 468-476页

作者： CHEN, Jian HU, Chang-Mingshanghai institute of Organic Chemistry, chinese academy of sciences, 354 Fenglin Lu, shanghai 200032, china shanghai institute of Organic Chemistry Chinese Academy of Sciences 354 Fenglin Lu Shanghai 200032 China

Potassium fluoride on alumina was proved to be an efficient dehydrohalogenating agent for the synthesis of per(poly)fluoroalkyl substituted alkenes and alkynes. The reaction was simple, mild and the yields ranged from... 详细信息

关键词： Potassium fluoride on alumina dehydrohalogenation synthesis per(poly)fluoroalkyl substituted alkenes and alkynes.

β-delayed proton decays near the proton drip line

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Science china(physics,Mechanics & Astronomy) 2005年第3期48卷 257-267页

作者： XU Shuwei 1 , LI Zhankui 1 , XIE Yuanxiang 1 , HUANG Wenxue 1 , SHU Nengchuan 2 , CHEN Yongshou 2 , XU Furong 3 , WANG Kun 4 , PAN Qiangyan 1 , WANG Xudong 1 , YU Yong 1 & XING Yebing 1 1. institute of Modern physics, chinese academy of sciences, Lanzhou 730000, china 2. Nuclear physics Department, china institute of Atomic Energy, Beijing 102413, china 3. Department of Technical physics, Peking University, Beijing 100871, china 4. shanghai institute for Nuclear Research, shanghai 201800, china 1. institute of Modern physics Chinese Academy of Sciences 730000 Lanzhou China 2. Nuclear physics Department China Institute of Atomic Energy 102413 Beijing China 3. Department of Technical physics Peking University 100871 Beijing China 4. shanghai institute for Nuclear Research 201800 Shanghai China

We briefly reviewed the experimental study on a-delayed proton decays near the proton drip line published by our group during the period of 1996―2004, namely the first observation of the a-delayed proton decays of 9 new nuclides in the rare-earth region and the new measurements of a-delayed proton decays of 5 nuclides in the mass ～90 region near the N = Z line with the aid of the “p-?” coincidence in combination with a He-jet tape transport system. In the meantime some important experimental technique details were supplemented. The experimental results, including the half -lives, spins, parities, deformations and production reaction cross sections for the 14 nuclei were summarized and compared with the current nuclear-model predictions, and then the following points were represented. (1) The experimental half-lives for 85Mo and 92Rh as well as the predicted “waiting point” nuclei 89Ru and 93Pd are 5―10 times longer than the theoretical predictions given by M?ller et al. using a macroscopic-microscopic model. It considerably influences the predictions of the abundances of the nuclides produced in the rp-process. (2) The current-model predictions are not consistent with the experimental assignments of the spins and parities for the proton drip-line nuclei 142Ho and 128Pm. However, the nuclear potential energy surface (PES) calculated by using a Woods- Saxon-Strutinsky method reproduced the experimental results. (3) The Alice code overestimated the production reaction cross sections of the studied 9 rare-earth nuclei by one order of magnitude or two, while HIVAP code overestimated them by one order of magnitude approximately.

关键词： proton drip line, β-delayed proton decay, He-jet tape transport system, "p-γ" coincidence, spin, parity, deformation, production reaction cross section.

The 5'-flanking cis-acting elements of the human ε-globin gene associates with the nuclear matrix and binds to the nuclear matrix proteins

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Cell Research 1998年第3期8卷 209-218页

作者： YAN ZHI JIANG RUO LAN QIAN(shanghai institute of Cell Biology, chinese academy of sciences, shanghai 200051, china) shanghai institute of Cell Biology Chinese Academy of Sciences Shanghai 200031 China

The nucleax mains attachment regions(MARs) and the binding nuclear matrix proteins in the 5'-flalildng cisacting elements of the humanε-globin gene have been examined. Using in vitro DNA-matrix binding assay,it has been shown that the positive stage-specific regulatory element (ε-PREII, -446bp-419bp) upstream of this gene could specifically associate with the nuclear matrix from K562 cells, indicating thatε-PREII mad be an erythroidspecilic facultstive MAR. In gel mobility shift assay and Southwestern blotting assal an eothroid-specific nuclear matrix protein (ε-NMPk) in K562 cells has been revealed to bind to this positive regulatory element (E-PREII). Furthermore, we demonstrated that the silencer (-392hp -177bp) uP8tream of the humanε-globin gene could associate with the nuclear matrices from K562, HEL and Raji cells. In addition, the nucleax matrix proteins prepared from these three cell lines could also bind to this silencer, suggesting that this silencer element linght be a constitutive nuclear mains attachment region (constitutive MAR). Our results demonstrated that the nucleax madrid and nuclear mains proteins lxilght play an important role in the regulation of the human 5-globin gene expression.

关键词： Human ε-globin gene nuclear matrix attachment regions nuclear matrix proteins K562 cells

Preparation of ^(67)Ga-EDTMP and its biodistribution studies

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Nuclear Science and Techniques 2003年第4期14卷 249-252页

作者： LI Qing-Nuan, ZHANG Xiao-Dong, ZHANG Yong-Ping, LI Wen-Xin (shanghai institute of applied physics, the chinese academy of sciences, shanghai 201800) shanghai institute of applied physics the Chinese Academy of Sciences 上海 201800

67Ga-EDTMP was synthesized in a single step by adding 67GaCl3 to EDTMP solution. Dependences ofthe radiolabeling yield of 67Ga-EDTMP on EDTMP concentration, pH and reaction time were examined. Under theoptimum conditions, the radiolabeling yield of 67Ga-EDTMP was more than 97%. A biodistribution experiment inmice showed that 67Ga-EDTMP was mainly absorbed by skeleton and reached 13.25% at 0.5 h after injecting, thenkept a high level in 72 h with a maximum value of 16.82% at 48 h. The results suggest that 67Ga-EDTMP might be apotential bone pain palliation radiopharmaceutical due to its high skeletal uptake, rapid blood clearance and relativelylow soft-tissue absorption. But further work must be done to determine whether 67Ga-EDTMP is useful in thetreatment of painful osseous metastases.

关键词：镓放射性同位素示踪核医疗学疾病诊断疾病治疗

Cleavage of Supercoiled Circular Double-stranded DNA Induced by a Eukaryotic Cambialistic Superoxide Dismutase from Cinnamomum camphora

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Acta Biochimica et Biophysica Sinica 2004年第9期36卷 609-617页

作者： Bao-Zhong WANG, Xu-Bin WEI&, and Wang-Yi LIU* State Key Laboratory of Molecular Biology, institute of Biochemistry and Cell Biology, shanghai institutes for Biological sciences,chinese academy of sciences, shanghai 200031, china State Key Laboratory of Molecular Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences

A eukaryotic cambialistic superoxide dismutase (SOD) has been purified to homogeneity from mature seeds of the disease- and insect-resistant camphor tree (Cinnamomum camphora). Besides the known role of this SOD in protecting cells against oxidative stress, it can induce the cleavage of supercoiled double-stranded DNA into nicked and linear DNA. It can not cleave linear DNA or RNA, demonstrating there is no DNase or RNase in the purified cambialistic SOD. Furthermore, the SOD can linearize circular pGEM-4Z DNA that is relaxed by topoisomerase I. This result indicates that the DNA-cleaving activity re- quires substrates being topologically constrained. The supercoiled DNA-cleaving activity of the cambialistic SOD can be inhibited by either SOD inhibitor (azide) or catalase and hydroxyl radical scavengers (ethanol and mannitol). The chelator of iron, diethylenetriaminepentaacetic acid (DTPA), also inhibits the supercoiled DNA-cleaving activity. These results show that the dismutation activity is crucial for the supercoiled DNA cleavage. The modification of tryptophan residue of the cambialistic SOD with N-bromosuccinimide (NBS) shows that these two activities are structurally correlative. The reaction mechanism is proposed that the hydroxyl radical formed in a transition-metal-catalyzing Fenton-type reaction contributes to the DNA- cleaving activity. In addition, the cleavage sites in supercoiled pGEM-4Z DNA are random.

关键词： cambialistic SOD Fenton-type reaction hydroxyl radical relaxed circular duplex DNA supercoiled DNA cleavage

Research progress in terahertz quantum cascade lasers

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Science china(Information sciences) 2012年第1期55卷 16-26页

作者： CAO JunCheng Key Laboratory of Terahertz Solid-State Technology,shanghai institute of Microsystem and Information Technology,chinese academy of sciences,shanghai 200050,china 1. Key Laboratory of Terahertz Solid-State Technology Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China

The terahertz(THz)quantum cascade laser(QCL)is a coherent THz source based on intersubband transitions of unipolar *** semiconductor lasers,THz QCLs are solid-state,electrically pumped,tunable,and can be easily *** paper reviews the state of the art for the design,operation temperature,and output power of THz *** applications in THz communication and imaging are also discussed.

关键词： terahertz quantum cascade laser communication imaging

Identification of γ1 subunit of GABAA receptor in rat testis

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Cell Research 2002年第1期12卷 33-37页

作者： JING HUA HU, YUAN CHANG YAN Lab of Molecular Cell Biology, institute of Biochemistry and Cell Biology, shanghai institutes for Biological sciences, chinese academy of sciences, shanghai 200031, china 1Lab of Molecular Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China 1Lab of Molecular Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China

The isoform type ofγsubunits of GABAA receptor is a molecular determinant of its pharmacological characteristics. At present, the existence of GABAA receptor in mammalian sperm is still a controversy. By using degenerate primers designed according to highly conserved region in all threeγ(γ1, γ2 andγ3) subunits cloned in rat brain, we performed reverse transcription polymerase chain reaction (RT-PCR) to examine the expression pattern of -γsubunits of GABAA receptor in rat testis. Only one 370 bp fragment was obtained from RT-PCR in rat testis and sequencing results showed that it representedγ1 subunit, but notγ2 orγ3 subunit. Using the cloned fragment as probe, a 3.8 kb transcript which in size as same asγ1 ubunit in rat brain was detected in rat testis mRNA by performing Northern blot assay. Furthermore, results of in situ hybridization assay confirmed thatγ1 subunit was expressed in round spermatids and spermatozoa, maybe also in secondary spermatocyte. These evidences proved that 71 subunit of GABAA receptor is exclusively expressed in rat testis and this feature may be the structural basis of the specific function of GABAA receptors in sperm acrosome reaction.

关键词： GABAA receptor rat testis γ1 subunit.

Embryonic and adult neural stem cell research in china

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Science china(Life sciences) 2010年第3期53卷 338-341页

作者： JIAO JianWei institute of Neuroscience,State Key Laboratory of Neuroscience,chinese academy of sciences,shanghai 200031,china 1. institute of Neuroscience State Key Laboratory of Neuroscience Chinese Academy of Sciences Shanghai 200031 China

Neural stem cells(NSCs) are one specific type of multipotential stem cells that have the ability to proliferate for a long time and to differentiate into neural cells,including neurons,astrocytes and *** NSCs exist in both the embryonic and adult central nervous system(CNS) of all mammalian *** has been made in the understanding of the developmental regulation of NSCs and their function in *** review discusses recent progress in this area,with emphasis on work done by investigators in china.

关键词： neural stem cells neurogenesis stem cell niche reprogramming hippocampus