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Electronic structure and magnetism of R(Fe,Si)_(12. (R=Y,Nd)

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Science china(Physics,Mechanics & Astronomy) 2006年第2期49卷 195-202页

作者： SUN Guang’ai1, CHEN Bo1, DU Honglin2. FAN Zhijian1, GAO Tao3 & QI Xinhua31. Institute of Nuclear Physics and Chemistry, china Academy of Engineering Physics, Mianyang 62.900, china 2. {2. of physics, peking university, Beijing {4., china 3. Institute of Atomic and Molecular Physics, Sichuan university, Chengdu 610065, china Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics Mianyang China department of physics Peking university Beijing China Institute of Atomic and Molecular Physics Sichuan University Chengdu China

The newly developed full-potential linearized augmented plane wave (LAPW) and local orbitals (lo) based on standard APW methods are briefly introduced, and the structure and magnetic properties of R(Fe, Si)12.compounds (R = Y, Nd) are calculated using the method. The distribution of Si at different sites is analyzed based on total energy of one crystal unit with structure having been optimized. The characters of magnetic mo-ments, total density of states (TDOS) and partial density of states (PDOS) for different crystal sites Si occupies are obtained and analyzed. The results show that the total mag-netic moments of RFe10Si2.(R = Y, Nd) are larger than those of RFe10M2.(M = Ti, V, Cr, Mn, Mo and W) and the hybridization mechanism is seen as follows. Si(8j) reduce the mag-netic moments of Fe at three sites, however, Si(8f) mainly reduce the magnetic moments of Fe(8i) and Fe(8j) atoms. The Curie temperature is markedly enhanced by the introduc-tion of Si atoms according to spin fluctuation of DOS at Fermi level.

关键词： (L)APW+lo method R(Fe Si)12.R = Y Nd) magnetic moment Density of state.

Role of inositol 1,4.5-trisphosphate receptors in α1-adrenergic receptorinduced cardiomyocyte hypertrophy

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Acta Pharmacologica Sinica 2006年第7期27卷 895-900页

作者： Da-li LUO~(2.3,5) Jian GAO~2.Xiao-mei LAN~3 Gang WANG~4.Sheng WEI~4.Rui-ping XIAO~4.Qi-de HAN~32.department of Pharmacology,School of Chemical Biology & Pharmaceutical Sciences,Capital university of Medical Sciences,Beijing 100069,china 3 Institute of Cardiovascular Science at Health Science Center,peking university Beijing 100083,china 4.Institute of Molecular Medicine and College of Life Science,peking university,Beijing {12.,china department of Pharmacology School of Chemical Biology & Pharmaceutical Sciences Capital University of Medical Sciences Beijing China Institute of Cardiovascular Science at Health Science Center Peking University Beijing China Institute of Molecular Medicine and College of Life Science Peking University Beijing China

Aim:Intracellular Ca2.plays pivotal roles in diverse cellular functions,includinggene transcription that underlies cardiac remodeling during stress ***,the role of inositol 1,4.5-trisphosphate receptors（IP3Rs）in the media-tion of cardiac intracellular Ca2.and hypertrophic growth remains *** with neonatal rat ventricular myocytes suggests that activation of IP3Rsmay be linked to α1adrenergic receptor（α1AR）increased stereotyped Ca2.sparkoccurrence and global Ca2.***,we hypothesized that Ca2.releasethrough IP3Rs was necessary for α1AR-stimulated cardiac ***:We used myoinositol 1,4.5-trisphosphate hexakis（butyryloxymethyl）ester（IP3BM）,a membrane-permeant ester of IP3,to activate IP3Rs directly,and Fluo 4.AM tomeasure intracellular Ca2.***:IP3BM(10μmol·L-1)mimicked theeffects of phenylephrine,a selective agonist of α1AR,in increments in local Ca2.spark release（especially in the perinuclear area）and global Ca2.*** importantly,IP3R inhibitors,2.aminoethoxydiphenyl borateand Xestospongin C,abolished the IP3BM-induced Ca2.responses,and signifi-cantly suppressed α1AR-induced cardiomyocyte hypertrophy assayed by cellsize,[3H]leucine incorporation and atrial natriuretic factor gene expression,dur-ing sustained（4. h）phenylephrine ***:These results,therefore,provide cellular mechanisms that link IP3R signaling to α1AR-stimulatedgene expression and cardiomyocyte hypertrophy.

关键词： inositol 1,4.5-trisphosphate receptors Ca2.sparks α1 adrenergic stimulation cardiac hypertrophy

SYNTHESIS AND BIOTECHNOLOGICAL APPLICATIONS OF VINYL POLYMERINORGANIC HYBRID AND MESOPOROUS MATERIALS

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Chinese Journal of Polymer Science 2000年第1期18卷 1-7页

作者： Yen Wei Kun-yuan Qiu department of Chemistry, Drexel university, Philadelphia, Pennsylvania 1910{2. USA department of Polymer Science and Engineering, peking university, Beijing {{2., china Drexel university 美国北京大学高分子科学与工程系北京

We describe the sol-gel synthesis of a new family of organic-inorganic hybrid materials, in which various vinyl polymers are covalently bonded to and uniformly distributed in inorganic oxide matrices. The materials can be tailored to have both good toughness and hardness while maintaining excellent optical transparency. Doping the sol-gel metal oxides with optically active compounds such as D-glucose results in new optical rotatory composite materials. Removal of the dopant compounds from the composites affords mesoporous oxide materials; which represents a new, nonsurfactant-templated route to mesoporous molecular sieves. We have successfully immobilized a series of enzymes and other bioactive agents in mesoporous materials. Catalytical activities of the enzyme encapsulated in mesoporous materials were found to be much higher than those encapsulated in microporous materials.

关键词： vinyl polymer-inorganic hybrid materials mesoporous materials sol-gel process biotech-nological applications

Intermediate processes and critical phenomena: Theory, method and progress of fractional operators and their applications to modern mechanics

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Science china(Physics,Mechanics & Astronomy) 2006年第3期49卷 257-272页

作者： XU Mingyu1 & TAN Wenchang2.1. Institute of Applied Mathematics, School of Math & System Science, Shandong university, Jinan 2.0100, china 2. State Key Laboratory of Turbulence and Complex Systems & {2. of Mechanics and Engineering Science, peking university, Beijing {4., china Institute of Applied Mathematics School of Math & System Science Shandong University Jinan China State Key Laboratory of Turbulence and Complex Systems & department of Mechanics and Engineering Science Peking University Beijing China

From point of view of physics, especially of mechanics, we briefly introduce fractional operators (with emphasis on fractional calculus and fractional differential equa- tions) used for describing intermediate processes and critical phenomena in physics and mechanics, their progress in theory and methods and their applications to modern me- chanics. Some authors’ researches in this area in recent years are included. Finally, prospects and evaluation for this subject are made.

关键词： fractional operators,intermediate processes,critical phenomena,modern mechanics

On the boundary value problem for harmonic maps of the Poincaré disc

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Chinese Science Bulletin 1997年第24期42卷 2025-2045页

作者： LI Zhongdepartment of Mathematics, peking university, Beijing {2., china department of Mathematics Peking University Beijing China

The boundary value problem for harmonic maps of the Poincare disc is discussed. The emphasis is on the non-smoothness of the given boundary values in the problem. Let T . be a subspace of the universal Teichmüller space, defined as a set of normalized quasisymmetric homeomorphisms h of the unit circle S onto itself where h admits a quasiconformal extension to the unit disc D with a complex dilatation μ satisfyingwhere ρ(z)|dz|2.is the Poincare metric of D. Let B . be a Banach space consisting of holomorphic quadratic differentials φ in D with normsIt is shown that for any given quasisymmetric homeomorphism h : S1→S1∈ T . , there is a unique quasiconformal harmonic map of D with respect to the Poincare metric whose boundary corresponding is h and the Hopf differential of such a harmonic map belongs to B .

关键词： Harmonic maps quasiconfomial mappings universal Teichmüller spaces.

Anatomical reinvestigation of Archaeopteris macilenta from the Upper Devonian(Frasnian) of South china

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Journal of Systematics and Evolution 2011年第6期49卷 590-597页

作者： Yun GUO De-Ming WANG(Key Laboratory of Orogenic Belts and Crustal Evolution,department of Geology,peking {2.,Beijing 100871,{4.) (Key Laboratory of Orogenic Belts and Crustal Evolution Department of Geology Peking University Beijing 100871 China)

Archaeopteris macilenta is one of the most widespread plants in the Late *** on fossils from the Frasnian Huangjiadeng Formation,Yichang District of Hubei Province,for the first time we study in detail the anatomy of this progymnosperm plant in South *** axes are protostelic with three xylem sympodia and lack secondary *** axes are eustelic,bearing eight sympodia and a thin band of secondary *** symmetrical sympodia of mesarch primary xylem produce traces of appendages in a spiral *** macilenta and ***(***)are dominant in the Frasnian and Famennian,*** with these two species from other tectonic plates indicate consistent stelar *** spread,continuous occurrence,and identical anatomy during the Late Devonian indicate that Archaeopteris survived the Frasnian-Famennian extinction *** this time,endemic genera and cosmopolitan taxa,including Archaeopteris,suggest the palaeogeographic isolation of South china and certain associations with other plates.

关键词： anatomy Archaeopteris Late Devonian palaeogeography progymnosperms South china.

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,{2. School of Mathematical Science, peking university, Beijing {4.,{2. 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.

On the Construction of Some New Harmonic Maps from R^m to H^m

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Acta Mathematica Sinica,English Series 2001年第2期17卷 301-304页

作者： Yuguang SHI department of Mathematics. peking university, Beijing {2., P. R. china department of Mathematics Peking University Beijing 100871 P. R. China

In this note, we const, ruct some new harmonic maps from R^m to H^m via symmetric methods.

关键词： Harmonic Maps Symmetric Methods

Raising approximation order of refinable vector by increasing multiplicity

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Science china Mathematics 2006年第1期49卷 86-97页

作者： YANG Shouzhi & PENG Lizhong department of Mathematics, Shantou university, Shantou 515063,{2. LMAM, School of Mathematical Sciences, peking university, Beijing {4.,{2. department of Mathematics Shantou University Shantou China LMAM School of Mathematical Sciences Peking University Beijing China

An algorithm is presented for raising an approximation order of any given orthogonal multiscaling function with the dilation factor a. Let φ(x) = [φ1(x),φ2.x),…,φr(x)]T be an orthogonal multiscaling function with the dilation factor a and the approximation order m. We can construct a new orthogonal multiscaling function φnew(x) = [ φT(x). f3r+1(x),φr+2.x),…,φr+s(x)}T with the approximation order m + L(L ∈ Z+). In other words, we raise the approximation order of multiscaling function φ(x) by increasing its multiplicity. In addition, we discuss an especial setting. That is, if given an orthogonal multiscaling function φ(x) = [φ1 (x), φ2.x), …, φr(x)]T is symmetric, then the new orthogonal multiscaling function φnew(x) not only raise the approximation order but also preserve symmetry. Finally, some examples are given.

关键词： orthogonal, multiscaling functions, approximation order, symmetry.