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Colossal magnetoresistance and spin-glass properties of La(1-x)TexMnO3(x=0.04,0.1)

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chinese Science Bulletin 2003年第13期48卷 1321-1324页

作者： TAN Guotai, DUAN Peng, DAI Shouyu, CHEN Zhenghao, LU Huibin & ZHOU Yueliang Laboratory of Optical Physics, institute of Physics & Center for Condensed Matter Physics, chinese academy of sciences, {2. 100080, China Correspondence should be addressed to Chen Zhenghao (e-mail: zhchen @***) Laboratory of Optical Physics Institute of Physics & Center for Condensed Matter Physics Chinese Academy of Sciences Beijing 100080 China

For the first time, a novel material of La1-x- TexMnO3 (x = 0.04, 0.1), in which the La ions are replaced by the nonmetal element Te in the Chalcogen, has been synthesized. The material has a rhombohedral lattice with the space group of R3c, and Te ions have a tetravalence state. The curves of the resistivity vs. temperature indicate that this material has the property of a metal-semiconductor transition and the colossal magnetoresistance (CMR) effect. The maximum magnetoreistance ratio MR=[(0)()]/(0)H? is about 51% at 4 T for x = 0.1. Besides, a spin-glass behavior at low magnetic fields is observed in this compound.

关键词：巨磁电阻 La1-xTexMnO3 镧碲物理性质

Moduli Space of ⅡB Superstring and SUYM in AdS5×S~5

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Communications in Theoretical Physics 2006年第2期45卷 301-314页

作者： HOU Bo-Yu~1 HOU Bo-Yuan~2.WANG Xiao-Hui~1 XIONG Chuan-Hua~1 YUE Rui-Hong~11 institute of Modern Physics,Northwest University,Xi’an 710069,China2.Graduate School,the chinese academy of sciences,{2. 100039,China

This paper consists of two parts,In part Ⅰ,we interpret the hidden symmetry of the moduli space of IIBsuperstring on AdS×S~5 in terms of the chiral embedding in AdS,which turns out to be the CP~3 conformal anne *** review how the position μ of poles in the Riemann-Hilbert formulation of dressing transformation and thevalue of loop parameter μ in the vertex operator of aNne algebra determine the moduli space of the soliton solutions,which describes the moduli space of the Green-Sehwarz *** show also how this affine SU(4) symmetryaffinizes the conformal symmetry in the twistor space,and how a soliton string corresponds to a Robinson congruencewith twist and dilation spin coeNcients μ of *** part Ⅱ,by extending the dressing symmetric action of IIB stringin AdS×S~5 to the Dbrane,we find a gauged WZW action of Higgs Yang-Mills field including the 2.cocycle of *** left and right twistor structures of left and right α-planes glue into an *** symmetry groupof Nahm equations is centrally extended to an affine group,thus we explain why the spectral curve is given by affineToda.

关键词： AdS/CFT correspondence Green-Schwarz superst ring affine Toda

Neutron Diffraction Studies of the Magnetic Structure of Ho_2.e_9Ga_(8～x)Alx

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chinese journal of nuclear physics 1997年第1期19卷 44-47页

作者： Chen Dongfeng Gou Cheng Sun Kai China institute of Atomic Energy,P.O.Box 2.5-30,beijing 102.13Yan Qiwei Zhang Panlin Shen Baogen Cheng Zhaohua State Key Laboratory of Magnetism,Intstitute of Physics,the{2.,P.O.Box 603,beijing 100080 中国原子能科学院北京中科院物理所磁学国家重点实验室北京

The crystallographic and magnetic structures of Ho2.e9Ga8～xAlx（x=2.4 and 6）arestudied by powder neutron diffraction at room *** atom fractional occupancies ofGa and AI and the atom magnetic moments of Ho and Fe are... 详细信息

The crystallographic and magnetic structures of Ho2./sub>Fe9Ga8～xAlx（x=2.4 and 6）arestudied by powder neutron diffraction at room *** atom fractional occupancies ofGa and AI and the atom magnetic moments of Ho and Fe are obtained by Rietveld *** magnetic structure of the phase with x=2.shows an easy-axis anisotropy and themagnetic moments of all atoms are parallel to c *** saturation magnetization and Curietemperatures of samples with x in the range 0～8 are investigated.

关键词： Neutron diffraction Magnetic structure

Atmospheric Mercury Pollution in beijing

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chinese Journal of Population,Resources and Environment 2009年第3期7卷 92-96页

作者： Guo Hongling1,2.1.institute of Forensic Science,Ministry of Public Security,beijing 100038,China 2.{2. People’s Public Security University,beijing 100038,China institute of Forensic Science Ministry of Public Security Beijing 100038 China chinese People's Public Security University Beijing 100038 China

The atmospheric mercury pollution in beijing is a serious *** mercury has three sources:natural emission,anthropogenic emission and previously deposited mercury reemission or recycling,composing elemental mercury,divalent mercury and particulate-phase *** studies showed that mercury in beijing's air was higher than the general level of mercury concentration in the *** emission sources were *** emissions,coal burning,vehicle exhaust emissions and waste incineration were thought to be the main sources of atmospheric mercury pollution in *** also meteorology has an effect on atmospheric mercury concentration in *** have been taken to control the emission of mercury into the air in recent years.

关键词： atmosphere mercury beijing

分子筛改性Co／SiO2.化剂对Fischer-Tropsch合成汽油类烃的影响

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石油化工 2008年第5期37卷 445-449页

作者：李宇萍王铁军吴创之吕永兴李海滨中国科学院可再生能源与天然气水合物重点实验室

在中孔SiO2.添加USY，HZSM-5，β分子筛组成双功能载体，并采用初湿浸渍法在载体上浸渍钴盐，制备了一系列分子筛改性的Co／SiO2.化剂，考察了分子筛的类型、HZSM-5分子筛的骨架硅铝比、HZSM-5分子筛在载体中的含量对Fischer-Tropsch... 详细信息

在中孔SiO2.添加USY，HZSM-5，β分子筛组成双功能载体，并采用初湿浸渍法在载体上浸渍钴盐，制备了一系列分子筛改性的Co／SiO2.化剂，考察了分子筛的类型、HZSM-5分子筛的骨架硅铝比、HZSM-5分子筛在载体中的含量对Fischer-Tropsch合成汽油类烃（C5-12.的影响。实验结果表明，载体中SiO2.分子筛共同作用，提高了催化剂的活性，并使产物分布向汽油类烃偏移，其中，以HZSM-5分子筛改性的Co／SiO2.化剂的催化性能最好。HZSM-5分子筛改性催化剂对催化性能的影响受其骨架硅铝比的影响。当骨架硅铝比n（SiO2.：n（Al2.3）=38、HZSM-5分子筛在载体中的质量分数为2.％时，CO转化率达到80％以上，汽油类烃的选择性高达55％，其中异构烷烃的选择性在10％以上。

关键词： Fischer-Tropsch合成钴/二氧化硅催化剂分子筛汽油类烃

Quantitative mitochondrial proteome of pancreatic INS-1β cells stimulated with prolonged high glucose using SILAC

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生物物理学报 2009年第S1期25卷 194-195页

作者： Xiulan Chen , Ziyou Cui , Junjie Hou, Zhensheng Xie, Peng Xue, Jing Li, Tanxi Cai, Fuquan Yang Proteomic Platform & National Laboratory of Biomacromolecules, institute of Biophysics, chinese academy of sciences, {2., China, 100101

Most type 2.diabetics are accompanied with deficiency of insulin secretion and hyperglycemia. It has reported that glucose-stimulated insulin secretion of β cell (GSIS)

关键词： SILAC INS cells stimulated with prolonged high glucose using SILAC Quantitative mitochondrial proteome of pancreatic INS-1 high

Distribution and carbon isotope composition of lipid biomarkers in Lake Erhai and Lake Gahai sediments on the Tibetan Plateau

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Distribution and carbon isotope composition of lipid biomark...

根据植被估算黄土高原的自然侵蚀和加速侵蚀──以安塞县为例

中国科学院地质与地球物理研究所第11届（2.11年度）学术年会

作者： Jincai Tuo~(a,*),Chenjun Wu~(a,b),Mingfeng Zhang~a,Ru Chen~(a,b) ~aKey Laboratory of Petroleum Resources Research,institute of geology and {2.,chinese academy of sciences,No.382.Donggang West Road,Lanzhou,730000,Gansu,China ~bGraduate University of the chinese academy of sciences,beijing,100039,China

Lipid biomarkers and carbon isotopes of n-alkanes,n-fatty acids,and n-alkan-2.ones were used to determine organic carbon sources to surface sediments in lakes Erhai and Gahai on the Tibetan *** sediment samples contained n-fatty acids with lower concentrations of n-alkanes and *** chain nalkanes in lake sediments were characteristic of a source mixture of epicuticular waxes of higher plants and submerged littoral zone plants while n-fatty acids sources were bacteria and floating and/or submergent macrophytes;the n-alkan-2.ones had a possible source in epicuticular waxes of higher plants and/or grass from catchment which entered the lake and were reworked by the *** samples examined from Lake Erhai had heavierδC values of bulk organic carbon and specific carbon compounds than samples from Lake Cahai and meadow *** heavier isotopic composition can be best interpreted by the enhanced productivity occurring in Lake Erhai due to its lower salinity and possibly to limited CO concentrations;for the latter,this may have enriched C in the dissolved inorganic carbon pool of the lake water.

关键词： Lipid biomarkers Carbon isotope composition Lake sediments Lake Qinghai Lake Erhai and Lake Gahai Tibetan Plateau

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水土保持通报 1995年第4期15卷 25-32页

作者：贾绍凤中国科学院国家计划委员会地理研究所

植被具有很好的水土保持作用。已有的研究成果证实：当森林郁被度或植被群落总盖度或森林覆盖度达到４０％左右时，植被的水土保持效益发生质的飞跃，较之裸荒地可减少土壤流失５０％以上；当植被群落总盖度达到８０％时，就能基本控制... 详细信息

植被具有很好的水土保持作用。已有的研究成果证实：当森林郁被度或植被群落总盖度或森林覆盖度达到４０％左右时，植被的水土保持效益发生质的飞跃，较之裸荒地可减少土壤流失５０％以上；当植被群落总盖度达到８０％时，就能基本控制水土流失。目前黄土高原的植被很差，以安塞县为例，林草总覆盖度只有４５％，而且群落盖度很低，大多在３０％～５０％。而若无人类破坏，在同样的气候、地质条件下，安塞县的自然植被类型为森林和疏林灌丛草原，植被群落总盖度在８０％、乃至９０％以上，根据植被的水土保持规律和有无人类破坏情况下的植被对比情况，计算了黄土高原安塞县无人类破坏情况下的自然侵蚀及其占目前的总侵蚀量的比重。结果表明：位于黄土高原丘陵沟壑区的安塞县，自然侵蚀仅占总侵蚀量的９．５５％，按最不利的情况估计也只占１６．７６％，而若按较有利的情况估计则只占２．０３％。说明人为加速侵蚀占目前黄土高原总侵蚀量的绝大部分。

关键词：植被水土保持自然侵蚀加速侵蚀黄土高原

Strangeness Production from NN collisions

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Strangeness Production from NN collisions