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Correlation Between Magnetovolume and Colossal Magnetoresistance Effects in Terbium Doped La-Sr-Mn-O Perovskite

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Chinese Physics Letters 2000年第5期17卷 373-375页

作者： WU Jian ZHANG Shi-Yuan YIN Shi-Long CAO Qing-Qi GU Kun-Ming DU You-Wei Mathematics and Physics Department Hohai UniversityNanjing 210098 National Laboratory of Solid State Microstructure Physics and Department of Physics Nanjing UniversityNanjing 210093

(La_(0.67)Tb_(0.33))_(2/3)Sr_(1/3)MnO_(3) has been studied in order to probe mechanisms responsible for the giant magnetore-sistonce ratios and the lattice effect in this kind of *** experiment has shown a strong connection between the magnetotransport and magnetovolume *** applied magnetic Geld not only gives rise to a large negative magnetoresistance(-900%)but also produces two different magnetovolume effects which reflect two different magnetostriction mechanisms in the compound.

关键词： properties. compound. magnetoresistance

Quantum Charge Transfer in Quasi-One-Dimensional Mixed Halide compound.

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Chinese Physics Letters 1998年第10期15卷 737-738页

作者： WEI Jian-hua LIU De-sheng XIE Shi-jie MEI Liang-mo Department of Physics Shandong UniversityJinan 250100

Intrinsic charge transfer in mixed halide compound. PtX_(x)X'_(1-x ) was studied in the framework of the two-band extended Pielerls-Hubbard *** was found that the number of transferred charges can be a fraction times of the electronic *** maximum amount of the transferred charges will occur at a certain proportion x for a given mixed compound.

关键词： compound. model. charges

Structural Regularities of the Transition Metal Complexes Containing o-Benzenedithiol (H_2bdt)——Synthesis and Structure of Fe_3(bdt)_3(PBu_3~n)_3

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Science China Chemistry 1993年第8期36卷 912-919页

作者：康北笙徐勇进吴达旭彭金海洪茂椿翁林红陈学太刘汉钦 State Key Laboratory of Structural Chemistry and Fujian Institute of Research on the Structure of Matter Academia Sinica Fuzhou 350002 PRC

Complex Fe_3(bdt)_3(PBu_3~n)_3 was synthesized in the presence of PBu_3~n and the structural regularities in a series of transition metal complexes containing bdtH_2 ligand were summarized. The title complex crystallizes in the triclinic space group P-, Mr=1195.19, cell parameters: a=13.283(3), b=20.115(5), c=13.156(3), (?)=90.33(2), β= 116.47 (1), γ=92.19(2)°, V=3143.5(2.7)~3, Z=2, d_c=1.26g/cm^3. The structure was solved by direct methods from 4122 unique reflections with I>4σ(I) and reached the final convergence factor of R(Rw) = 0.053 (0.060). The complex exhibits strong paramagnetism.

关键词： o-benzenedithiol ligand thiolate and phosphine-mixed coordinated complex structural regularity trinuclear iron cluster compound.

Preparation of Metal Particle Catalysts Wrapped in Organosilicon compound.via Metal Vapor Synthesis

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Science China Chemistry 1993年第10期36卷 1153-1160页

作者：黄唯平吴世华赵维君白令君张宝龙王序昆杨瑞华 Department of Chemistry Nankai University Tianjin 300071 PRC

Three kinds of metal catalysts Ni/D4, Ni-Mn/D4, Ni-Mn-La/D4, wrapped in organosilicon compound.were prepared by metal vapor synthesis. Their feature was characterized with XRD, TEM, XPS, FMR and static magnetic measurement. The metal particle size in catalysts was less than 3.5 am. The results of XPS showed that the metals in the catalysts existed in zero and other valent state. Inner metal, as an organosilicon compound.folded around the metal particle, was protected from oxidation. FMR and static magnetic measuremeat revealed that metal particles were spheroidal and of superparamagnetism. Of all the caralysts the catalytic activity of Ni-Mn-La/D4was the highest in hydrogenating furfuraldehyde into furfuralcohol.

关键词： metal vapor synthesis superparamagnetism ferromagnetic resonance metal catalyst organosilicon compound.

Heavy fermion quantum criticality: The party is just beginning

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Science China(Physics,Mechanics & Astronomy) 2020年第11期63卷 129-130页

作者： Yi-Feng Yang Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Songshan Lake Materials Laboratory Dongguan 523808China

Recently,Nature reported the discovery of a ferromagnetic quantum critical point(FM QCP)in the heavy fermion compound.CeRh6Ge4[1].This is the first discovery of such kind in a stoichiometric *** FM order is suppressed at a critical pressure of 0.8 GPa,beyond which the ground state turns into a Fermi ***,Science had also reported the observation of a FM QCP,albeit in the doped compound.YbNi4(P0.92As0.08)2[2].

关键词： compound. quantum compound

Effects of Annealing on Pt/Co Multilayer Films

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Chinese Physics Letters 1994年第3期11卷 169-172页

作者： JIANG Zhihong SHEN Defang SHI Tiansheng GUO Changlin GUO Rongfa Shanghai Institute of Metallurgy Academia SinicaShanghai 200050 Shanghai Institute of Ceramics Academia SinicaShanghai 200050

Annealing effects are helpful guides to study Pt/Co multilayer interface ***,the results reported till now are *** we report the increase in coercivity Hc and the decrease in Kerr rotationθk after being annealed in v... 详细信息

关键词： compound. annealed multilayer

Reconstitution activity of partial metallocluster-deficient molybdenum-iron protein of nitrogenase with a series of molybdenum-sulfur compound.

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Chinese Science Bulletin 1997年第10期42卷 868-871页

作者： Xu, JQ Nan, YM Liu, Y Zhou, XH Chen, YD Niu, SY Wang, TG Huang, JF Luo, AL Wang, ZP Zhong, ZP Li, JG Department of Chemistry Jilin University Changchun China Institute of Botany Chinese Academy of Sciences Beijing China

RECENTLY,the structure of MoFe protein from Azotobacter vinelandii has been deter-mined,and based on this,the structural models of FeMo-co and P-clusters in MoFe proteinhave been *** to the model,FeMo-co consists of two clusters,Fe4S3 andMoFe3S3 with a homocitrate ligand coordinated to Mo atom,bridged by three nonprotein lig-ands,two of which are inorganic sulfur atoms and the other is nitrogen- or

关键词： MoFe protein nitrogenase molybdenum-sulfur compound.

Carbazole-type compound. in crude oils

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Chinese Science Bulletin 1998年第8期43卷 669-672页

作者： Min Zhang Tingsheng Xiang Bowen Mei Jianghan Petr Inst Anal & Res Ctr Jingzhou 434102 Peoples R China

Carbazole_type compound. were analyzed using GC and GC_MS_MS. A relatively high concentration of carbazole_type compound. was detected in crude oils of different types (marine and non_marine) and different maturities (low mature and mature) in Tarim, Liaohe and Keilu basins. The results suggest the ratios of 1, 8-dimethyl-/2, 7-dimethylcarbazole and benzo carbazole/benzo carbazole might be taken as petroleum migration parameters.

关键词： crude oil carbazole_type compound.

THE CRYSTAL STRUCTURE AND THE ROOM TEMPERATURE SECTION OF TERNARY PHASE DIAGRAM IN THE SYSTEM Gd-Fe-Ti

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Science China Mathematics 1992年第11期35卷 1327-1335页

作者：田静华梁敬魁解思深陈赤王艳芹 Institute of Physics Academia Sinica Beijing 100080 PRC Undergraduate form Tsinghua University in 1989

The Gd-Fe-Ti ternary system has been investigated by means of X-ray diffraction, and its room temperature section determined, in which two ternary intermetallic compound., GdFe_(11)Ti and GdFe_9Ti_2, have been observed. GdFe_(11)Ti has a tetragonal structure, belonging to the type ThMn_(12), with a space group I4/mmm, and the lattice parameters at room temperature a=0.8522nm, c=0.4790nm, c/a=0.562, z=2. The observed density is 7.82 g/cm^3 and the calculated density is 7.84g/cm^3. The Curie temperature of GdFe_(11)Ti is 349℃. GdFe_9Ti_2 has a tetragonal structure, belonging to the type Ce (Mn_(0.55)Ni_(0.45))_(11), with a space group P4/mbm. The lattice parameters at room temperature are a=0.8245nm, c=0.4832 nm,c/a=0.586, and z=2. The observed density is 7.6g/cm^3 and the calculated density is 7.64 g/cm^3.

关键词： phase diagram crystal structure rare earth compound.