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Representations of Real and Complex Stability Radii of 2-Dimensional LinearSystems

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International Journal of Minerals,Metallurgy and Materials 1999年第4期13卷 299-301页

作者： Lequan Min1.2 Ning Song1(l Applied science School, University of science and technology’ Beijing, Beijing 100083, china2 china center of advanced science and technology, Beijing 100080, china) Univ Sci & Technol Beijing Appl Sci Sch Beijing 100083 Peoples R China china Ctr Adv Sci & Technol Beijing 100080 Peoples R China

Rigorous proofs are given for the representations of real and complex stability' radii of 2-dimensional linear systems. This representations can be used to analyze the robustness of a nominal 2-dimensional linear system under pelturbation of the system parameters, in particular testing the effect of numerical algorithms which are used to calculate the real stability radii of higher dimensional piecewise-linear systems.

关键词： linear systems robustness stability radii

High-pressure synthesis and properties of CeO_2-ZrO_2 solid solution

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Chinese science Bulletin 2001年第10期46卷 801-806页

作者： XU Dapeng, WANG Quanyong, LU Zhe, LIU Zhiguo, ZHANG Gongmu & SU Wenhui1. Department of Physics, Jilin University, Changchun 130023 china 2. International center for Materials Physics, Chinese Academy of sciences, Shenyang 110015, china 3. center for Condensed Matter and Radiation Physics, china center of advanced science and technology (World Laboratory), Beijing 100080, china Department of Physics Jilin University Changchun China International center for Materials Physics Chinese Academy of Sciences Shenyang China center for Condensed Matter and Radiation Physics China Center of Advanced Science and Technology (World Laboratory) Beijing China

Using nanoparticles of CeO2 and ZrO2 prepared by the chemical precipitation method as starting materials, the single-phase cubic Ce0.5Zr0.5O2 solid solution (c-Ce0.5Z0.5O2) has been synthesized under 3.1 GPa at 1073 K for the first time. The structure of the c-Ce0.5Zr0.5O2 has not been changed before and after annealing at 773 K for 1 h. Only an unknown EPR signal (g =1.990) has been observed in the c-Ce0.5Zr0.5O2 and not varied after annealing at 773 K for 1 h, which exhibited that there exists no Ce3+ in the c-Ce0.5Zr0.5O2 and the Ce4+ has not been reduced into Ce3+ after annealing. The transport mechanism is ionic for the c-Ce0.5Zr0.5O2. The bulk conductivity (a =1.2×10-5 S/cm at 823 K, σ=2.1 ×10-3 S/cm at 1123 K) is the same as that of CeO2, but smaller than that of Y2O3-stabilized ZrO2. A marked curvature at T = 823 K has been observed in the Arrhenius plot of the bulk conductivity. The activation energy below 823 K is lower than that above 823 K, and the reason has been discussed.

关键词： CeO2-ZrO2 nanocrystalline high-pressure and -temperature solid-state reaction solid solution.

BRST quantization and canonical Ward identity of the supersymmetric electromagnetic interaction system

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science china(Physics,Mechanics & Astronomy) 2007年第3期50卷 339-347页

作者： HUANG YongChang1,3,4, JIANG YunGuo1 & LI XinGuo2,3 1 Institute of Theoretical Physics, College of Applied sciences, Beijing University of technology, Beijing 100022, china 2 Institute of Modern Physics, Chinese Academy of sciences, Lanzhou 730000, china 3 center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Collisions, Chinese Academy of sciences, Lanzhou 730000, china 4 china center of advanced science and technology (World Laboratory), Beijing 100080, china 1. Institute of Theoretical Physics College of Applied Sciences Beijing University of Technology Beijing 100022 China 3. center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Collisions Chinese Academy of Sciences Lanzhou 730000 China 4. china center of advanced science and technology (World Laboratory) Beijing 100080 China 2. Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China

According to the method of path integral quantization for the canonical constrained system in Becchi-Rouet-Stora-Tyutin scheme, the supersymmetric electromagnetic interaction system was quantized. Both the Hamiltonian of the supersymmetric electromagnetic interaction system in phase space and the quantization procedure were simplified. The BRST generator was constructed, and the BRST transforma- tions of supersymmetric fields were gotten; the effective action was calculated, and the generating functional for the Green function was achieved; also, the gauge generator was constructed, and the gauge transformation of the system was ob- tained. Finally, the Ward-Takahashi identities based on the canonical Noether theorem were calculated, and two relations between proper vertices and propaga- tors were obtained.

关键词： supersymmetric electromagnetic interaction BRST quantization Ward identity

Nonfactorizable B→xc0K Decay and QCD Factorization

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Communications in Theoretical Physics 2007年第11期48卷 885-890页

作者： MENG Ce~1 GAO Ying-Jia~1 CHAO Kuang-Ta~(1,2)1 Department of Physics,Peking University,Beijing 100871,china2 china center of advanced science and technology (World Laboratory),Beijing 100080,china

We study the unexpectedly large rate for the factorization-forbidden decay B→xK within the QCDfactorization *** use a non-zero gluon mass to regularize the infrared divergences in vertex ***-point singularities arising from spectator corrections are regularized and carefully estimated by the off-shellness *** find that the contributions arising from the vertex and leading-twist spectator corrections are numericallysmall,and the twist-3 spectator contribution with chiral enhancement and linear end-point singularity becomes *** reasonable choices for the parameters,the branching ratio for B→xK decay is estimated tb be in the range(2～4)×10,which is compatible with the Belle and BaBar data.

关键词： B meson decay QCD factorization charmonium

J/Ψ and ηc Decays into Some Hadronic States

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J/Ψ and ηc Decays into Some Hadronic States

γ Radiative Decays to Light Quark Jets and Color Octet Mechanism

第九届全国粒子物理学术会议

作者： Fang Shuang-shi(Representing BES Collaboration ) china center for advanced science and technology,Beijing

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Communications in Theoretical Physics 2006年第12期 1017-1022页

作者： GAO Ying-Jia,~1 ZHANG Yu-Jie,~1 and CHAO Kuang-Ta~(1,2) 1 Department of Physics, Peking University, Beijing 100871, china 2 china center of advanced science and technology (World Laboratory), Belling 100080, china

We study radiative decays of T to light quark jets in nonrelativistic QCD by taking both the color singlet and color octet b5 operators into consideration. The cut for quark jet energy and cut for the angle between two quark jets are introduced. The sensitivity to the soft and collincar singularities in the loop integrals are greatly reduced by these cuts. With the jet energy cut of about 1 GeV, and the jet angle cut of about 36°, the branching ratio for γ→γqqis found to be 8.2×10;from color singlet contributions. The color octet contributions could be much larger than that of color singlet, depending on the estimate of the color octet matrix elements. This process may provide a new test for the color octet mechanism in nonrelativistic QCD.

关键词： radiative decay jet color octet

Revised Iterative Solution for Groundstate of Schr(?)dinger Equation

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Communications in Theoretical Physics 2004年第7期 37-42页

作者： ZHAO Wei-Qin china center of advanced science and technology (CCAST), (World Lab.), P.O. Box 8730, Beijing 100080, china Institute of High Energy Physics, the Chinese Academy of sciences, P.O. Box 918(4-1),Beijing 100039, china chinacenterofadvancedscienceandtechnology（CCAST）（WorldLab.）P.O.Box8730Beijing100080China

A revised iterative method based on Green function defined by quadratures along a single trajectory isproposed to solve the low-lying quantum wave function for Schrdinger *** a new expression of theperturbed energy is obtained,which is much simpler than the traditional *** method is applied to solve theunharmonic oscillator *** revised iteration procedure gives exactly the same result as those based on thesingle trajectory quadrature method.A comparison of the revised iteration method to the old one is made using theexample of Stark *** obtained results are consistent to each other after making power expansion.

关键词： single trajectory quadrature Green function revised iterative solution

Thermodynamic correction to the perturbation of strong interaction

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Thermodynamic correction to the perturbation of strong inter...

A new way of transformation from a-quartz to coesite

CCAST“研究禁闭与退禁闭相变的连续场论途径”研讨会

作者： G. X. Peng china center of advanced science and technology (World Laboratory), Beijing 100080, china Institute of High Energy Physics, Chinese Academy of sciences, Beijing 100039, china

＜正＞The properties of quark matter from perturbativo QCD have thermodynamic inconsistencies. A thermodynamically determined new term can solve the problem, serving as a likely way from perturbative to non-perturbative effects. Consequently, quark matter can be self bound at about 4 times the normal nuclear saturation density, and the density behavior of sound velocity becomes opposite to the previous finding, which alters the mass-radius relation significantly to allow pulsars to be a candidate of quark stars.

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Progress in Natural science:Materials International 2006年第10期16卷 1090-1097页

作者： SU Wenhui, LIU Shue, XU Dapeng, WANG Weiran, YAO Bin, GUO Xingyuan, LIU Zhiguo, and ZHONG Zheng ( center for the Condensed Matter science and technology, Harbin Institute of technology, Harbin 150001, china center for Rare-Earth Solid State Physics, Jilin University, Changchun 130023, china International center for Materials Physics, Chinese A-cademy of sciences, Shenyang 110015, china center for Condensed Matter and Radiation Physics, china center of advanced science and technology (World Laboratory), Beijing 100080, china Department of Physics, University of Windsor, Windsor, ON N9B 3P4, Canada) center for Rare-Earth Solid State Physics Jilin University Changchun 130023 China International center for Materials Physics Chinese Academy of Sciences Shenyang 110015 China center for Condensed Matter and Radiation Physics China Center of Advanced Science and Technology (World Laboratory) Beijing 100080 China center for the Condensed Matter science and technology Harbin Institute of Technology Harbin 150001 China Department of Physics University of Windsor Windsor ON N9B 3P4 Canada

A laboratory method combining the high-energy mechanical ball milling and high static pressure has been suggested for modelling synthesis of coesite in the Earth's crust. A window of milling time, a mechanical collision-induced intermediate phase ofα-quartz and its condition of easily crystallizing into coesite under the condition of 3.0 GPa, 923 K, science research and implied the other possible mechanism of coesite formation in the Earth's crust.

关键词： quartz-coesite high-energy mechanical ball milling high state pressure Raman spectrum metastable phase sub-duction-exhumation of plate.