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A template of rat brain based on fMRI T2. imaging

Progress in Natural Science:Materials International 2005年第6期15卷 502-506页

作者： HU Zhenghui1, WU Yigen2. WANG Xiaochuan3, WANG Jianzhi3, CHEN Feiyan1 and TANG Xiaowei1*(1. Department of Physics and Bio-X laboratory, Zhejiang University, Hangzhou 31002., china 2. {2. of high energy Physics and key laboratory of Nuclear Analysis Techniques, chinese academy of sciences,beijing 100039, china 3. Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, china) Department of Physics and Bio-X laboratory Zhejiang University Hangzhou 310027 China institute of high {2. Physics and key laboratory of Nuclear Analysis Techniques Chinese Academy of Sciences Beijing 100039 China Department of Pathophysiology Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China

The development of functional magnetic resonance imaging (fMRI) technology has made it possible to carry out functional brain imaging experiments in small animals. Usually, group data is required to form the assessment of population, which can not only increase the sensitivity of the overall experiment, but also allow the generalization of the conclusion to the whole population. In order to average the signals of functional brain images from different subjects, it is necessary to put all the mapping images into the same standard space (template image). However, up to now, most animal brain templates remain unavailable and it must be done by ourselves. In this study, a template image based on the brains of eight male Wistar rats is obtained, and it is successfully used in our present Alzheimer disease (AD)-like rat model studies as template for spatially normalizing images to the same stereotaxical space. The fMRI results processed with statistical parametric mapping (SPM99) software are in agreement with the results from immunohistochemical experiment, which proves that this method is universally applicable to the pathologic models of other small animals and to human brain lesion studies.

关键词： fMRI animal model atlas template normalization T*2.

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Validity of the Bouchet's complementary relationship at 102.observatories across china

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Science china Earth sciences 2009年第5期52卷 708-713页

作者： YU JingJie1,2.ZHANG YongQiang3,LIU ChangMing1,2.1 institute of Geographic sciences and Natural Resources Research,{2.,beijing 100101,china 2.key laboratory of Water Cycle and Related Land Surface Processes,{2.,beijing 100101,china 3 CSIRO Land and Water,PO Box 1666,Canberra ACT 2.01,Australia institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China key laboratory of Water Cycle and Related Land Surface Processes Chinese Academy of Sciences Beijing 100101 China CSIRO La

Bouchet in 1963 hypothesized that for large homogeneous land surface with minimum advection of heat and moisture,there exists a 1:1 complementary relationship of potential and actual evaporation coupled through land-atmosphere *** complementary relationship has been widely used to estimate regional actual evaporation and explain the pan evaporation *** examine the standardized potential evaporation(potential evaporation divided by wet environment evaporation) at 102.observatories at different elevations across ***,the relationship is appropriate at the low elevations(energy budget because of lower vapor pressure deficit and stronger global solar *** a result,at the high elevations(over 1000 m),the excess energy resulted by limited moisture availability is not enough to be converted into drying power of the *** result suggests that the complementary relationship is asymmetric at the high elevations.

关键词： evaporation complementary relationship elevation china

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Low-temperature magnetic properties of horse spleen ferritin

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chinese Science Bulletin 2010年第27期55卷 3174-3180页

作者： TIAN LanXiang 1,2.CAO ChangQian 1,2.LIU QingSong 1,2.&PAN YongXin 1,2.1key laboratory of the Earth’s Deep Interior,{2. of Geology and Geophysics,chinese academy of sciences,beijing 10002.,china 2.ranco-chinese Biomineralization and Nano-structures laboratory,beijing 10002.,china key laboratory of the Earth''s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Franco-chinese Biomineralization and Nano-structures laboratory Beijing 100029 China

The magnetic properties of the antiferromagnetic cores in ferritin are of importance in the construction and improvement of ferritin-based magnetic resonance imaging systems and their application to environmental *** this study,we carry out integrated magnetic and transmission electron microscopy analyses of horse spleen ferritin(HoSF)to understand the relationships between the magnetic behavior of HoSF and temperature,applied field and grain-size *** R-value from the Wohlfarth-Cisowski test for the investigated sample at 5 K was 0.46,indicating very weak magnetostatic interactions among the nanoparticles of *** nanoparticles of HoSF show superparamagnetic properties at room temperature,while below the blocking temperature of Tb≈12.K it has a net magnetic moment that comes from the uncompensated spins of the nanoparticle surface or *** thermal relaxation process of HoSF follows the Néel-Arrhenius *** low-temperature AC susceptibility data,we calculated the effective magnetic anisotropy energy Ea=(5.52.0.16)×10-2. J;the effective magnetic anisotropy energy constant Keff=(4.65±0.14)×10 4 J/m3 and the pre-exponential frequency factor f0 =(4.52.2.93)×1011 *** values are useful in understanding the magnetic behavior of the antiferromagnetic nanoparticles and their potential application in biomedical technology.

关键词：马脾铁蛋白低温度磁性质透射电子显微镜磁各向异性常数纳米粒子生物医学技术交流磁化率

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AFM study on the adsorption and aggregation behavior of dissolved humic substances on mica

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Science china Chemistry 2006年第3期49卷 256-266页

作者： GE Xiaopeng1, ZHOU Yanmei2. Lü Chunhua1 & TANG Hongxiao1 1. State key laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental {2., chinese academy of sciences, beijing 100085, china 2. School of Civil Engineering & Architecture, beijing Jiaotong University, beijing 100044, china 1. State key laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China 2. School of Civil Engineering & Architecture Beijing Jiaotong University Beijing 100044 China

Humic substances constitute the major organic fractions of soils, sediments and natural waters, and play a dominant role in the binding, mobilization, transport and ultimate fate of organic contaminants in subsurface systems. In this paper, two humic acid samples, Guanting and Tianjin, with different origin and chemical compositions have been investigated with AFM imaging for their adsorption and aggregation behaviors on mica. While the Tianjin humic sample is found to form small spheres with 2.0 to 330 nm in diameter at lower concentrations, irregular loop-chain assemblies of hundreds of nanometer in diameter with the chain width of about 40 nm are dominant for the Guanting humic sample, which may attribute to the more polar aliphatic fractions in the chemical composition in the latter. The heterogeneous and polydisperse nature of humic substances with multiple structural features, such as sponge-like structures, perforated sheets, aggregate of spheres, branches and chain-like assemblies etc., is apparent at higher concentrations for both humic samples, showing morphologically new evidence for the dominant view of the humic dual-mode sorption model. With naphthalene introduced, the assemblies of Guanting humic substances clearly become more compact with significantly narrowed branches and less porous the perforated sheet-like structures. It is indica- tive of that smaller nanometer scale rings present along the perforated assemblies could potentially represent hydrophobic domains, which may facilitate the adsorption and aggregation of naphthalene onto the natural particle surfaces and therefore lead to an important role of dissolved humic sub- stances in the sorption of environmental pollutants.

关键词： atomic force microscopy (AFM) dissolved humic substances morphology aggregation adsorption

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Role of gallium wetting layer in high-quality ZnO growth on sapphire (0001) substrates

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Science china(Physics,Mechanics & Astronomy) 2004年第5期47卷 612-620页

作者： ZENG Zhaoquan1,3, WANG Yong2. DU Xiaolong1, MEI Zengxia1, KONG Xianghe3, JIA Jinfeng1, XUE Qikun1 & ZHANG Ze2. 4 1. State key laboratory for Surface Physics, {2. of Physics, chinese academy of sciences, beijing 100080, china 2. laboratory of Electron Microscopy, {2. of Physics, chinese academy of sciences, beijing 100080, china 3. College of Physics and Engineering, Qufu Normal University, Qufu 2.3165, china 4. beijing University of Technology, beijing 10002., china 1. State key laboratory for Surface Physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 2. College of Physics and Engineering Qufu Normal University 273165 Qufu China 3. laboratory of Electron Microscopy Institute of Physics Chinese Academy of Sciences 100080 Beijing China 4. beijing University of Technology 100022 Beijing China

A Ga wetting layer was used to modify the surface structure of sapphire (0001) substrate to prepare high-quality ZnO film by radio frequency plasma-assisted molecule beam epitaxy. We found that this Ga layer plays a crucial role in eliminating 30 rotation domains, controlling polarity and decreasing defect density in ZnO epilayers, as demonstrated by in situ reflection high {2. electron diffraction, ex situ high resolution X-ray diffraction and high resolution cross-sectional transmission electron microscopy. Zn-polar film of ZnO was determined by convergent beam electron diffraction. A Ga bilayer model is proposed to understand the effects of the Ga wetting layer on high-quality ZnO growth.

关键词： Ga wetting layer, sapphire, polarity, defect density, zinc oxide, rf-MBE, RHEED, HRXRD, TEM, CBED.

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Graphene-based hybrid materials and their applications in energy storage and conversion

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chinese Science Bulletin 2012年第23期57卷 2983-2994页

作者： ZHOU Ding 1,2.CUI Yi 1,2.& HAN BaoHang 1,2.1 National Center for Nanoscience and Technology,beijing 100190,china 2.State {2. laboratory of Transducer Technology,chinese academy of sciences,Shanghai 2.0050,china National Center for Nanoscience and Technology State key laboratory of Transducer Technology Chinese Academy of Sciences

Graphene attracts more and more scientists and researchers owing to its superior electronic,thermal,and mechanical *** material scientists,graphene is a kind of versatile building blocks,and considerable progress has been made in recent ***-based hybrid materials have been prepared by incorporating inorganic species and/or cross-linking of organic species through covalent and/or noncovalent *** graphene-based hybrid materials show improved or excellent performance in various *** this review,we summarize the synthesis of graphene and graphene-based hybrid materials,and their applications in energy storage and conversion.

关键词： graphene hybrid material energy storage energy conversion

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Correlation of Behavior Changes and BOLD Signal in Alzheimer-like Rat Model

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 803-810页

作者： Zheng-Hui HU#, Xiao-Chuan WANG1#, Li-Yun LI3, Mai-Li LIU3, Rong LIU1, Zhiqun LING1, Qing TIAN1, Xiao-Wei TANG, Yi-Gen WU2., and Jian-Zhi WANG1* Department of Physics and Bio-X disciplinary laboratory, Zhejiang University, Hangzhou 31002.,china 1 Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, china 2.3} of high energy Physics and key laboratory of Nuclear Analysis Techniques, chinese academy of sciences, P.O. Box 918, beijing 100039, china 3Wuhan institute of Physics and Mathematics, State key laboratory of Magnetic Resonance and Atomic and Molecular Physics, chinese academy of sciences, Wuhan 430071, china Department of Physics and Bio-X disciplinary laboratory Zhejiang UniversityHangzhou 310027China Department of Pathophysiology Tongji Medical College Huazhong University of Science and TechnologyWuhan 430030 China Wuhan institute of Physics and Mathematics State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Chinese Academy of SciencesWuhan 430071 China institute of high {2. Physics and key laboratory of Nuclear Analysis Techniques Chinese Academy of SciencesP.O. Box 918 Beijing 100039 China

To explore a potential means for the early diagnosis of Alzheimer disease, we studied the relationship of resting T2. signal and tau hyperphosphorylation/spatial memory deficit. The rat model with tau hyperphosphorylation and spatial memory deficit was established by bilateral hippocampi injection of isoproterenol (IP). Then, the correlative alteration between resting T2. signal and spatial memory retention was assessed with blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) study and Morris Water Maze test, and Western blot was employed to confirm tau hyperphosphorylation. The analysis showed following results. (1) Tau phosphorylation at Ser396/Ser404 and Ser199/Ser2.2.was signifi- cantly increased in IP-injected rats as detected by PHF-1 and tau-1, respectively. (2. An AD-like spatial memory retention disturbance was induced at 2. h after isoproterenol injection. (3) A sensitivity threshold of resting T2. signal intensity, which separated the IP-treated rats from vehicle control, was obtained by applying linear regression analysis, and an estimated sensitivity statistical threshold was at 32.62. These results suggest that resting T2. signal may serve as a noninvasive quantitative marker in predicting AD-like spatial memory deficits and tau hyperphosphorylation.

关键词： Alzheimer disease (AD) functional magnetic resonance imaging (fMRI) isoproterenol (IP) Morris Water Maze diagnosis

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MODIFICATION OF EPOXY RESIN WITH POLYSILOXANE BEARING PENDANT QUATERNARY AMMONIUM GROUPS

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chinese Journal of Polymer Science 2002年第6期20卷 537-541页

作者： Zuo-xin Huang Ying Huang Yun-zhao Yu The State key laboratory of Engineering Plastics, {2. of Chemistry chinese academy of sciences, beijing 100080 china chinese Acad Sci Inst Chem State Key Lab Engn Plast Beijing 100080 Peoples R China

Polysiloxane bearing pendant quaternary ammonium groups (PSI) was used to modify the surface properties of epoxy resins. In the cured resin, PSI formed the dispersed phase. Remarkable enrichment and gradient distribution of polysiloxane on the surface region of the epoxy resins were demonstrated by XPS analysis. The composition and properties of the surface of PSI-modified epoxy resin, which is in contact with the mold, are dependent on the material of the mold. Through the incorporation. of PSI, epoxy resins with low surface energy and low friction coefficient were obtained. Polysiloxane with lower ionic group content shows a higher degree of enrichment on the resin surface and leads to a higher contact angle against water, while the polysiloxane having optimum compatibility with the epoxy resin shows a greater effect in reducing the static friction coefficient of the resin against glass.

关键词： polysiloxane epoxy resin surface composition friction coefficient

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Anomalous magnetotransport in LaMn_(1-x)Te_xO_3

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Science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 987-992页

作者： TAN GuoTai1,2. CHEN ZhengHao3 & ZHANG XiaoZhong4,5 1 key laboratory of Beam Technology & Materials Modification of the Ministry of Education, {2. of Low energy Nuclear Physics, beijing Normal University, beijing 100875, china 2.beijing Radiation Center, beijing 100875, china 3 laboratory of Optical Physics, {2. of Physics, {12., beijing 100080, china 4 key laboratory of Advanced Materials of the Ministry of Education, Department of Materials Science and Engineering, Tsinghua University, beijing 100084, china 5 beijing National Center for Electron Microscopy, Tsinghua University, beijing 100084, china 1. key laboratory of Beam Technology & Materials Modification of the Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing 100875 China 2. beijing Radiation Center Beijing 100875 China 3. laboratory of Optical Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China 4. key laboratory of Advanced Materials of the Ministry of Education Department of Materials Science and Engineering Tsinghua University Beijing 100084 China 5. beijing National Center for Electron Microscopy Tsinghua University Beijing 100084 China

The LaMn1-xTexO3+δ (x=0.1, 0.2. 0.3) were synthesized using solid-state reaction method for the first time. X-ray photoemission spectrum (XPS) shows that in the samples the Te ions have a valence of Te4+, and Mn3+ ions are partly converted into Mn2. and Mn4+ due to the excess oxygen and Te doping. The magnetotransport associated with Mn2., Mn3+ and Mn4+ was investigated. The experimental results show that the samples are insulator at 0 T when the amount of Mn3+ is much larger or less than the sum of Mn2. and Mn4+; by contrast, the samples display metal to insulator transition with increasing temperature when the amount of Mn3+ is close to the sum of Mn2. and Mn4+. These anomalous magnetotransport behaviors were analyzed in the frame of the double-exchange (DE) mechanism.

关键词： colossal magnetoresistance La-Te-Mn-O magnetotransport

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Current distribution and stability of LTS/HTS hybrid superconducting conductors

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Science china(Technological sciences) 2010年第7期53卷 2000-2007页

作者： GUAN XiaoJin1,2. WANG YinShun1 & ZHOU WeiWei3 1 key laboratory of HV and EMC {2., North china Electric Power University, {2. 102.06, china 2.Department of Physics, Baoding University, Baoding 071000, china 3 institute of Electrical Engineering, chinese academy of sciences, {2. 100190, china 1. key laboratory of HV and EMC {2. North China Electric Power University Beijing 102206 China2. Department of Physics Baoding University Baoding 071000 China3. Institute of Electrical Engineering Chinese Academy of Sciences Beijing 100190 China

Current distribution and stability of a hybrid LTS/HTS superconductor, consisting of multifilamentary NbTi/Cu and Bi2.2./Ag tapes, were numerically analyzed according to power-law models. The results showed that most of current passed through the LTS and the current increased in the HTS with temperature rise when the transport current was below the critical current of the hybrid conductor. The quench propagation velocity of the hybrid conductor was smaller but its minimum quench energy was larger than those of LTS conductors, indicating that the stability of the hybrid superconducting conductor was effectively improved and a high engineering current density was simultaneously achieved. Finally, a hybrid sample, made by soldering Bi2.2./Ag tape onto NbTi/Cu conductor, was prepared and tested successfully at helium temperature. The experimental results qualitatively agreed with the simulated ones.

关键词： distribution hybrid conductor minimum quench energy quench propagation velocity n value stability

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