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Boundedness for commutators of fractional Hardy operators on Herz spaces

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Progress in Natural Science:Materials International 2007年第1期17卷 20-25页

作者： FU Zunwei, LIU Zongguang and LU Shanzhen ( School of Mathematical Sciences, beijing normal {2., beijing 100875,{4. department of Mathematics, Linyi normal {2., Linyi 2.6005,{4. department of Mathematics,{4. {2. of Mining and Technology, beijing 100083,{4.) [a]School of Mathematical Sciences Beijing Normal University Beijing China [b]Departhent of Mathematics Linyi Normal University Linyi China [c]Departhent of Mathematics China University of Mining and Technology Beijing China

Some boundedness results are established for commutators generated by classical fractional Hardy operators and one-sided CMO functions on the homogeneous Herz spaces, which extends some known results.

关键词： fractional Hardy operator Hardy’s integral inequality commutator one-sided CMO function homogeneous Herz space.

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 {2. university,beijing {4.,china 2.School of Mathematical Sciences,Capital {2. university,beijing 10004.,china 3 School of Mathematics,Jilin university,Changchun 130012.china 4.department of Statistics,university of Missouri,Columbia,MO 652.1,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, 2.06） and several approaches have been proposed for the additive hazards model with univariate current status data （Linet M., 1998; Martinussen and Scheike, 2.02.. 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

Eigenvalues, inequalities and ergodic theory

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Chinese Science Bulletin 2000年第9期45卷 769-774页

作者： CHEN Mufadepartment of Mathematics, beijing {2. university,{4., china department of Mathematics Beijing Normal University Beijing China

This paper surveys the main results obtained during the period 1992.1999 on three aspects mentioned in the title. The first result is a new and general variational formula for the lower bound of spectral gap (i.e. the first non-trivial eigenvalue) of elliptic operators in Euclidean space, Laplacian on Riemannian manifolds or Markov chains (?). Here, a probabilistic method -coupling method is adopted. The new formula is a dual of the classical variational formula. The last formula is actually equivalent to Poincare inequality. To which, there are closely related logarithmic Sobolev inequality, Nash inequality, Liggett inequality and so on. These inequalities are treated in a unified way by using Cheeger’s method which comes from Riemannian geometry. This consists of ?2. The results on these two aspects are mainly completed by the author joint with F. Y. Wang. Furthermore, a diagram of the inequalities and the traditional three types of ergodicity is presented (?3). The diagram extends the ergodic

关键词： eigenvalue inequality ergodic theory Markov process.

Hawking radiation and thermodynamics of a Vaidya-Bonner black hole

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Research in Astronomy and Astrophysics 2010年第1期10卷 33-38页

作者： Zhen-Feng Niu Wen-Biao Liu department of physics Hebei North University Zhangjiakou 075000 China department of physics Institute of Theoretical Physics Beijing Normal University Beijing 100875 China

Using Parikh＇s tunneling method, the Hawking radiation on the apparent horizon of a Vaidya-Bonner black hole is calculated. When the back-reaction of particles is neglected, the thermal spectrum can be precisely obtained. Then, the black hole thermodynamics can be calculated successfully on the apparent horizon. When a relativistic perturbation is applied to the apparent horizon, a similar calculation can also lead to a purely thermal spectrum. The first law of thermodynamics can also be derived successfully at the new supersurface near the apparent horizon. When the event horizon is thought of as a deviation from the apparent horizon, the expressions of the characteristic position and temperature are consistent with the previous viewpoint which asserts that the thermodynamics should be based on the event horizon. It is concluded that the thermodynamics should be constructed exactly on the apparent horizon while the event horizon thermodynamics is just one of the perturbations near the apparent horizon.

关键词： black hole physics -- relativity -- kinematics and dynamics

Theoretical studies on the mechanism of the thermal decarboxylation and decarbonylation of a number of α-keto-acids

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Chinese Journal of Chemistry 1995年第6期13卷 487-492页

作者： CHEN,Li-Tao CHEN,Guang-Ju FU,Xiao-YuanChemistry department,beijing {2. university,beijing 100875,china Chemistry department Beijing Normal University Beijing 100875 China

Both processes of decarboxylation and decarbonylation of a number of acids including RCOCO2.,R=H,CH3,CH2.,CF3,CH=CH2.Ph,OH have been studied by semi-empirical MO theory AMI method to verify the reaction mechanism of each process and the effect of different substituents on *** calculated results are consistent with the experimental reports and can be summed up as follows:(1) The decarboxylation of these acids to form aldehydes and carbon dioxide is concerted and takes place through a 4.membered ring transition state in which a partial negative charge develops on the carbon of the α-carbonyl group,so that the inductive effect of some substituents is favourable for this process.(2. Their decarbonylation into carboxylic acids and carbon monoxide however is the attack of the OH on the carbon of the alkyl portion of the acid,forming a 3-membered ring transition state.(3) The activation energy of decarbonylation is lower than that of decarboxylation,since oxygen is more nucleophilic than hydrogen and also the strong OH bond need not to be broken.

关键词： Decarboxylation decarbonylation a-keto-acid

Coupling, spectral gap and related topics (Ⅱ)

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Chinese Science Bulletin 1997年第18期42卷 1409-1416页

作者： CHEN Muf adepartment of Mathematics, beijing {2. university,{4., china department of Mathematics Beijing Normal University Beijing 100875 China

THIS is the second one of a series of three reviews. The ideas introduced in the last review are used to study the estimate of spectral gap and four classes of typical eigenvalue problems on manifolds. The comparison ... 详细信息

关键词： diffusions manifold Markov chains spectral gap couplings.

First-principles calculations on implanted TiO_2.by 3d transition metal ions

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Science china(physics,Mechanics & Astronomy) 2009年第6期52卷 838-842页

作者： HOU XingGang1,2. HUANG MeiDong1, WU XiaoLing2.& LIU AnDong2.1 department of physics, Tianjin {2. university, Tianjin 300387,{4. 2.Key Laboratory of Beam Technology and Material Modification of Ministry of Education, beijing {2. university, beijing 100875,{4. department of physics Tianjin Normal University Tianjin 300387 China Key Laboratory of Beam Technology and Material Modification of Ministry of Education Beijing Normal University Beijing 100875 China

3d transition metal (V, Cr and Fe) ions are implanted into TiO2.by the method of metal ion implantation. The electronic band structures of TiO2.films doped 3d transition metal ions have been analyzed by ab initio band calculations based on a self-consistent full-potential linearized augmented plane-wave method within the first-principle formalism. Influence of implantation on TiO2.films is examined by the method of UV-visible spectrometry. The results of experiment and calculation show that the optical band gap of TiO2.films is narrowed by ion implantation. The calculation shows that the 3d state of V, Cr and Fe ions plays a significant role in red shift of UV-Vis absorbance spectrum.

关键词： 3d transition metal ions implantation TiO2 FP-LAPW electronic structure

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, Institute of Low Energy Nuclear physics, {2. normal university,{4., china 2.{2. Radiation Center,{4., china 3 Laboratory of Optical physics, Institute of physics, Chinese Academy of Sciences, {2. 100080, china 4.Key Laboratory of Advanced Materials of the Ministry of Education, department of Materials Science and Engineering, Tsinghua university, {2. 100084. china 5 {2. National Center for Electron Microscopy, Tsinghua university, {2. 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

Complete multiple round quantum dense coding with quantum logical network

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Chinese Science Bulletin 2007年第9期52卷 1162-1165页

作者： LI ChunYan1,2.LI XiHan1,2.DENG FuGuo1,2.3,ZHOU Ping1,2.& ZHOU HongYu1,2.3 1 Key Laboratory of Beam Technology and Material Modification of Ministry of Education,beijing normal {2.,beijing {4.,china 2.Institute of Low Energy Nuclear physics,and department of Material Science and Engineering,beijing normal {2.,beijing {4.,china 3 beijing Radiation Center,beijing {4.,china Key Laboratory of Beam Technology and Material Modification of Ministry ofEducation Beijing Normal University Beijing 100875 China

We present a complete multiple round quantum dense coding scheme for improving the source ca-pacity of that introduced recently by Zhang et al. The receiver resorts to two qubits for storing the four local unitary ope... 详细信息

关键词：量子通信多重量子紧凑编码量子逻辑网络量子纠缠