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Proton induced X-ray emission (PIXE) analysis of sources of porcelain body of Ru Guan and Jun Guan porcelains

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Science china(physics,Mechanics & Astronomy) 2006年第4期49卷 411-420页

作者： LI Guoxia1, ZHAO Weijuan1, LI Rongwu2, SUN Hongwei1, GUO Min1, WANG Yanfang1, LIU Hui1, ZHAO Qingyun3, SUN Xinmin3, ZHAO Wenjun3 & CHENG Huansheng4.1. Faculty of Physical Engineering, Zhengzhou university, Zhengzhou 4.0052, china 2. department of physics,{4., beijing 100875. china 3. Institute of Cultural Relic and Archaeology of Henan Province, Zhengzhou 4.0000, china 4. Institute of Modern physics, Fudan university, Shanghai 2004.3, china Faculty of Physical Engineering Zhengzhou University Zhengzhou 450052 China department of physics Beijing Normal University Beijing 100875 China Institute of Cultural Relic Archaeology of Henan Province Zhengzhou 450000 China Institute of Modern physics Fudan University Shanghai 200433 China

34.samples of Ru Guan porcelain body and 50 samples of Jun Guan porcelain body (both kinds being in different body colors) were selected with the purpose of finding out the source of raw materials and their classification relationship so as to search for ways of non-destructive discrimination. Proton induced X-ray emission (PIXE) has been applied to these samples to determine their chemical elements. The data of seven major chemical elements collected from these samples were further studied through fuzzy cluster analysis. Results indicate that the origin of raw materials of Jun Guan porcelain body samples is comparatively more concentrated in certain places, while that of Ru Guan porcelain body samples is scattered about. The places of origin of raw materials of the majority of Ru Guan and Jun Guan porcelain body samples have something in common, but some differences still exist. It might be an important way for non-destructive discrimination among Ru Guan and Jun Guan porcelains by combining PIXE with fuzzy cluster analysis.

关键词： Ru Guan and Jun Guan porcelain, source of porcelain body, PIXE, fuzzy cluster analysis, non-destructive discrimination.

Weighted weak type estimates for commutators of the Marcinkiewicz integrals

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Science china Mathematics 2004年第1期47卷 83-95页

作者： DING Yong, LU Shanzhen & ZHANG Pudepartment of Mathematics, beijing normal university, beijing 100875. china department of Information and Computing Science, Zhejiang Institute of Science and Technology, Hangzhou 310033, {4. 1. department of Mathematics Beijing Normal University 100875 Beijing China 2. department of Information and Computing Science Zhejiang Institute of Science and Technology 310033 Hangzhou China

In this paper the authors give the weighted weak LlogL type estimates for a class of the higher order commutator generated by the Marcinkiewicz integral and a BMO function. In addition, the weak type norm inequalities... 详细信息

关键词： Marcinkiewicz integral, commutator, Ap weight, weak type estimate.

Efficient estimation for additive hazards regression with bivariate current status data

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Science china Mathematics 2012年第4期55卷 763-774页

作者： TONG XingWei 1,,HU Tao 2 & SUN JianGuo 3,4.1 School of Mathematical Sciences,beijing normal university,beijing {4.china 2 School of Mathematical Sciences,Capital normal university,beijing 10004.,china 3 School of Mathematics,Jilin university,Changchun 130012,china 4.department of Statistics,university of Missouri,Columbia,MO 65211,USA 1. School of Mathematical Sciences Beijing Normal University Beijing 100875 China2. School of Mathematical Sciences Capital Normal University Beijing 100048 China3. School of Mathematics Jilin University Changchun 130012 China4. Department of Statistics University of Missouri Columbia MO 65211 USA

This paper discusses efficient estimation for the additive hazards regression model when only bivariate current status data are available. Current status data occur in many fields including demographical studies and tumorigenicity experiments （Keiding, 1991; Sun, 2006） and several approaches have been proposed for the additive hazards model with univariate current status data （Linet M., 1998; Martinussen and Scheike, 2002）. For bivariate data, in addition to facing the same problems as those with univariate data, one needs to deal with the association or correlation between two related failure time variables of interest. For this, we employ the copula model and an efficient estimation procedure is developed for inference. Simulation studies are performed to evaluate the proposed estimates and suggest that the approach works well in practical situations. An illustrative example is provided.

关键词： bivariate current status data copula model counting processes efficient estimation joint survivalfunction

An asymptotic result of super-Brownian motion on hyperbolic space

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Chinese Science Bulletin 1997年第15期42卷 1240-1244页

作者： TANG Jiashandepartment of Mathematics, beijing normal university, beijing 100875. china Institute of Mathematics, Shantou university, Shantou 515063, {4. department of Mathematics Beijing Normal University Beijing China Institute of Mathematics Shantou University Shantou China

SUPERPROCESS is one kind of measure-valued branching Markov processes. In the recentdecades many results of superprocesses on Euclidean spaces and on general abstract spaces havebeen obtained, but there is only little work on Riemannian manifold. In this note, wewill consider the super-Brownian motions on the hyperbolic space of dimension d and give anasymptotic result of this process (see Corollary 1 below). Iscoe investigated a similar prob-

关键词： hyperbolic space radial super-Brownian motion hitting probability asymptotic.

Formation of 3-Arylpyrazolines and 1-Aroylethyl-3-arylpyrazolines via 3-Aroylethylsydnone with HCl in Ethyl Acetate

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Chinese Chemical Letters 1998年第9期9卷 803-804页

作者： Zhan Bin ZHANG Cheng Lie YIN Yong Ren WU (department of Chemistry, beijing normal university, beijing 100875. beijing normal Univ Dept Chem Beijing 100875 Peoples R China

Treatment of 3-aroylethylsydnone 1 with HCl leads to 3-arylpyrazoline 2 or 1-aroylethyl-3-arylpyrazoline 3 under different conditions.

关键词： sydnone pyrazoline hydrolysis

Weighted Boundedness for a Class of Rough Multilinear Operators

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Acta Mathematica Sinica,English Series 2001年第3期17卷 517-526页

作者： Yong DING Shan Zhen LU department of Mathematics,beijing normal university,beijing 100875.P.R.china E-mail:dingy@*** lusz@*** department of Mathematics Beijing Normal University Beijing 100875 P. R. China

In this paper we give the (L^p(ω~p),L^q(ω~q)) boundedness for a class of multilinear operators, which is similar to the higher-order commutator for the rough fractional *** our results the kernel function is merely ... 详细信息

关键词： Multilinear operator Fractional integral Rough kernel BMO A(p,q) weight

Ab initio studies on the pyrolysis mechanism of 2-haloacetic acids in the gas phase

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Chinese Journal of Chemistry 1995年第1期13卷 10-18页

作者： CHEN, Li-Tao CHEN, Guang-Ju FU, Xiao-YuanChemistry department, beijing normal university, beijing 100875. china Chemistry department Beijing Normal University Beijing 100875 China SU.EDU

The dehydrohalogenation mechanism of 2-haloacetic acids (XCH2CO2H, X=F, Cl and Br) has been studied theoretically by HF/3-21G and AM1 methods. The results indicate that these reactions are most probably proceeded in terms of a polar five-membered cyclic transition state in the gas phase. Their microscopic processes are beleived to be a stepwise reaction and the rate-determining step is the first one. By comparing the energy barriers of different 2-haloacetic acids, it can be realized that 2-fluoroacetic acid is easier to react than 2-chloroacetic and 2-bromoacetic acids.

关键词： 2-Haloacetic acid pyrolysis reaction mechanism transition state.

Asymmetric Photocatalyzed Addition of Cyclic Ammes to the Chiral 5-(l)-Menthyloxy-2(5H)-furanone

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Chinese Chemical Letters 1999年第11期10卷 889-892页

作者： Zhao Yang WANG Tian Ying JIAN Qing Hua CHEN(department of Chemistry,beijing normal university, beijing 100875. department of Chemistry Beijing Normal University Beijing 100875 China

The benzophenone-initiated photoaddition of N-methyl ammes 2 to the chiral synthon1 proceeds in a regiospecitlc and highlyr stereocontrolled thshion to give the C-C photoadductscontaining a ne\viy stereogenic center 3a-3c. The enantiomerically pure N-C photoadducts, aminobutenolides 5a-5c have been obtained from the enantioselective photoaddition of secondary cyclicammes 4.with the chiral synthon 1 under the same conditions.

关键词： Asymmetric photocatalysed conjugate addition enantiomerically pure C-Cphotoadducts. secondary cyclic amine enantiomerically pure N-C photoaducts.

Ab Initio MO Studies on the Reaction Mechanism for Carbonyl Insertion Catalyzed by Carbonyl Cobalt Complex

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Chemical Research in Chinese Universities 2000年第1期16卷 31-35页

作者： LEI Ming FENG Wen-lin and XU Zhen-feng (department of Applied Chemistry, beijing university of Chemical Technology,beijing 100029, P. R. {4. department of Chemistry, beijing normal university, beijing 100875. P. R. {4.) beijing Univ Chem Technol Dept Appl Chem Beijing 100029 Peoples R China beijing normal Univ Dept Chem Beijing 100875 Peoples R China

Ab initio method, under the effective core potential(ECP) approximation at HF/LANL2DZ level, has been employed to study the reaction mechanism of the carbonyl insertion of olefin hydroformylation catalyzed by a carbonyl cobalt HCo(CO)_3. The two reaction paths have been discussed. The calculated potential energy barriers for the carbonyl migration and the ethyl group migration are 105. 0 kJ/mol and 39. 17 kJ/mol, respectively. The results indicate that the reaction path via ethyl migration is more energetically favorable than that via carbonyl insertion.

关键词： Carbonyl Cobalt Hydroformylation Ab initio method Effective core potential