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INTERFACIAL REACTIONS OF METAL FILMS WITH AlN SUBSTRATE

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中国有色金属学会会刊：英文版 1996年第2期6卷 81-85页

作者： He Xiangjun Tao Kun Fan Yudian (department of materials science and engineering, Tsinghua university, beijing 100084) department of materials science and engineering Tsinghua University Beijing 100084 China

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关键词： thin films interfacial reactions AlN substrate

The localization of 1-cohomology of transitive Lie algebroids

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science china Mathematics 2006年第2期49卷 277-288页

作者： CHEN Zhuo & LIU Zhangju department of Mathematics, Capital normal university, beijing 100037, china School of Mathematical science, Peking university, beijing 100871, china department of Mathematics Capital Normal University Beijing China School of Mathematical science Peking University Beijing China

For a transitive Lie algebroid A on a connected manifold M and its representation on a vector bundle F, we define a morphism of cohomology groups rk: Hk(A,F) → Hk(Lx,Fx), called the localization map, where Lx is the adjoint algebra at x ∈ M. The main result in this paper is that if M is simply connected, or H (LX,FX) is trivial, then T is injective. This means that the Lie algebroid 1-cohomology is totally determined by the 1-cohomology of its adjoint Lie algebra in the above two cases.

关键词： transitive Lie algebroid representation cohomology localization.

Discrepancy of the magnetic behaviors and crystalline structure on the Co/FeMn and FeMn/Co interfaces with ultrathin Pt spacer

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Rare Metals 2010年第5期29卷 473-479页

作者： LIU Yang,FU Yanqiang,JIN Chuan,and FENG Chun department of materials Physics and Chemistry,university of science and Technology beijing,beijing 100083,china department of materials Physics and Chemistry University of Science and Technology Beijing Beijing China

The exchange coupling at the ferromagnetic/antiferromagnetic （FM/AFM） interface is influenced by both the magnetic structure and the crystalline micro-structure. Co/FeMn/Co thin films with 0.4 nm Pt spacer layer inserted into the Co/FeMn and FeMn/Co interface respectively were deposited by means of magnetron sputtering. The two interfaces upon and beneath the FeMn layer show distinct behaviors before and after the Pt spacer inserted. There is a remarkable shrink of the interracial uncompensated spins within the FeMn bottom interracial monolayers, whereas a relaxation of the pinning strength of the FeMn interfacial spins along the out-of-plane direction occurs at the top in- terface. XRD analysis indicates the Pt layer upon the FeMn layer forms an fcc （002） texture, implying the magnetic discrepancy between the top and bottom FeMn interfaces has crystalline structural origins.

关键词： interfaces exchange coupling exchange bias spacer stress anisotropy lattice match

CREEP BEHAVIOR OF AN EASY ORIENTED Ti-48Al PST CRYSTAL

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中国有色金属学会会刊：英文版 1996年第4期6卷 82-86页

作者： Lin Jianguo Zhou Yajian Zhang Yonggang Chen Changqi(department of materials science and engineering)(beijing university of Aeronautics and Austronautics,beijing 100083) department of materials science and engineering Beijing University of Aeronautics and Austronautics Beijing 100083 China

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关键词： TiAl alloy PST crystal creep behavior

X-RAY TOPOGRAPHIC STUDY OF HYDROGEN DAMAGE IN Fe-3 wt-% Si ALLOY

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Acta Metallurgica Sinica(English Letters) 1993年第8期6卷 87-91页

作者： WANG Yanbin WANG Anrong CHU Wuyang XIAO Jimei university of science and Technology beijing,beijing,china associate professor,department of materials Physics,university of science and Technology beijing,beijing 100083,china beijing Univ of science and Technology Beijing China

The formation and aggravation of hydrogen damage in Fe-3 wt-％ Si alloy during cathodic charging Were studied by means of Lange transmission X-ray *** showed that hydrogen damage did not form in the specimens charged in 0.5 mol/L H_2S0_4 so- lution without poison,and occurred with addition of 250 mg/L As_2O_3 even at very low charge current *** charging at a certain current density,the size of the damage may enlarge up to a limit yet no more by prolonged *** damage size increased with increase of charging current density,but not so apparent at high current density. An external tensile stress could promote the formation of hydrogen damage obviously. It seems that for charging in H_2SO_4 solution containing poison,the drop of hydrogen permeation curve against time prolongation is due to the formation of hydrogen damages.

关键词： hydrogen embrittlement X-ray topography Fe-3 wt-%Si alloy

Compactness of the commutators of parabolic singular integrals

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science china Mathematics 2010年第10期53卷 2633-2648页

作者： CHEN YanPing1 & DING Yong2,3 1department of Mathematics and Mechanics,university of science and Technology beijing,beijing 100083,china 2School of Mathematical science,beijing normal university,beijing 100875,china 3Laboratory of Mathematics and Complex Systems (BNU),Ministry of Education of china,beijing 100875,china department of Mathematics and Mechanics University of Science and Technology Beijing Beijing China School of Mathematical science Beijing Normal University Beijing China Laboratory of Mathematics and Complex Systems (BNU) Ministry of Education of China Beijing China

In this paper,the authors prove that the commutator [b,T] of the parabolic singular integrals is a compact operator on Lp(Rn)(1 < p < ∞) if and only if b ∈ VMO(Rn,ρ).The result is substantial improvement and extens... 详细信息

关键词： parabolic singular integrals commutators compactness BMO VMO

Oxidation Behavior of Micro-Crystalline Coatings of 310S Stainless Steel

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International Journal of Minerals,Metallurgy and materials 1998年第1期12卷 51-56页

作者： Zhenyu Liu Wei Gao Karl Dahm Yedong He (department of Chemical and materials engineering, The university of Auckland, New Zealand)(materials science and engineering School, university of science and Technology beijing, beijing 100083, china) department of Chemical and materials engineering University of Auckland Beijing New Zealand materials science and engineering School University of Science and Technology Beijing Beijing 100083 China

Micro-crystalline coatings of 310S stainless steels were produced by unbalanced magnetron sputter deposition. Isothermal oxidation behavior of the coated and uncoated specimens has been studied using a thermogravimetric analysis (TGA) station. The oxidation time was 50h and the temperature was 1 000℃. The oxidation rates of thecoated specimens was found to be much lower than the uncoated specimens after 50 h of oxidation. The oxidationkinetic curves of the coated specimens consisted of three stages : approximately parabolic at the first stage, speedingup at the second stage, and slow down at the third stage. The increase of the oxidation rate at the second stage nasattributed to the fast diffuison of Fe though the fine grained Cr2O3 layer formed on the micro-crystalline *** top view and cross-section microstructures of the oxides formed on the coated and the uncoated specimens werestudied with SEM and EDS. It was observed that the nucleation of oxide on the coated specimens was muchenhanced at the initial oxidation stage. This was explained as the result of reduction in the critical free energychange and increase in the supply of chromium ions.

关键词： oxidation 310S stainless steel magnetron sputter deposition oxide nucleation

Synthesis and Structural Characterization of One-dimensional Polynuclear Complex [La(bipyN_2O_2)(TFA)_3]_n

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Chinese Chemical Letters 2000年第10期11卷 935-936页

作者： Wen Xiang ZHU, Yun HE (department of Chemistry, beijing normal university, beijing 100875) (department of Pharmacy, beijing Staff Medical College, beijing 100036) department of Chemistry Beijing Normal University Beijing 100875 China department of Pharmacy Beijing Staff Medical College Beijing 100036 China

A novel polymeric complex [La(bipyN2O2)(TFA)3]n(TFA= trifluoroacetylacetone) was prepared. The X-ray structure analysis revealed that the complex has an infinite one-dimensional supramolecule structure with the 4,4'-bipyridyl-N,N'-dioxide as a bridge. La(III) is coordinated to eight oxygen atoms, six from three trifluoroacetylacetonate anions, two from two 4,4'-bipyridyl-N,N'-dioxide molecules.

关键词： Lanthanum polynuclear complex trifluoroacetylacetone 4,4'-bipyridyl-N,N'-dioxide.

Optimal reactions for the synthesis of superheavy nucleus ^(270)Hs

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science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 641-648页

作者： LIU Zuhua1,3 & BAO Jingdong1,2 1. Key Laboratory of Beam Technology and Material Modification of Ministry of Education, beijing normal university, beijing 100875, china 2. Physics department, beijing normal university, beijing 100875, china 3. china Institute of Atomic Energy, beijing 102413, china Key Laboratory of Beam Technology and Material Modification of Ministry of Education Beijing Normal University Beijing China china Institute of Atomic Energy Beijing China Physics department Beijing Normal University Beijing China

The superheavy nucleus 270Hs is expected to be a “double-magic” deformed nucleus. We have calculated its cross sections of evaporation residue for the reactions 248Cm(26Mg,4n)270Hs, 244Pu(30Si,4n)270Hs, 238U(36S,4n)270Hs and 226Ra(48Ca,4n)270Hs using a two-parameter Smoluchowski equation. It is found from our results that 226Ra(48Ca,4n)270Hs and 238U(36S,4n)270Hs are two optimal reactions for the synthesis of the superheavy nucleus 270Hs due to their large negative Q-values.

关键词： diffused fusion barrier,Smoluchowski equation,superheavy nuclei.