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Direct CP violation in hadronic B decays

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Science china(Physics,Mechanics & Astronomy) 2006年第3期49卷 357-366页

作者： HONG Bihai1,2.& Lü Caidian3 1. department of Physics, Lishui university, Lishui 32.000,{2.a 2. department of Physics, Shanghai Jiaotong university, Shanghai 2.0030, china 3. Institute of High Energy Physics, Beijing 100049,{2.a department of Physics Lishui University Lishui 323000 China department of Physics Shanghai Jiaotong University Shanghai 200030 China Institute of High Energy Physics Beijing 100049 China

There are different approaches for the hadronic B decay calculations, recently. In this paper, we upgrade three of them, namely factorization, QCD factorization and the perturbative QCD approach based on kT factorization, using new parameters and full wave functions. Although they get similar results for many of the branching ratios, the direct CP asymmetries predicted by them are different, which can be tested by recent experimental measurements of B factories.

关键词： CP violation hadronic B decay factorization.

Bipolar charged aerosol agglomeration and collection by a two-zone agglomerator

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Journal of Environmental Sciences 2001年第3期13卷 276-279页

作者： XIANG Xiao dong 1, CHEN Bao zhi 1, COLBECK I 2.(1. School of Resource and Civil Engineering, Northeastern university, Shenyang 110006, china. 2. Institute for Environmental Research, {2. of Biological and Chemical Sciences, university of Es School of Resource and Civil Engineering Northeastern University Shenyang 110006 China.

In older to collect fine particles more efficiently, a new-type electrostatic agglomerator with two zones was developed. The distinguishing feature of this electrostatic agglomerator is that the particles are bipolarly charged and coagulated in the same alternating electric field simultaneously. The silica flour with 2.fun mass median diameter and the smoke from burning wood powder were used as test aerosol. The comparison experimental results have shown that when the mean electric field is 4 kV/cm the collection efficiency of the new electrostatic agglomerator was 98.2. for silica flour and 67.4% for wood powder smoke, Under the same experimental condition. the collection efficiency of the electrostatic agglomerator with three zones was 97.4% for collecting silica flour and the collection efficiency of the electrostatic precipitator was 56.3% for wood powder smoke.

关键词： charged particle agglomeration alternating electric field electrostatic agglomerator (EA) electrostatic precipitator (ESP) collection efficiency

Regulation of aging by NELF-A and RNA polymerase Ⅱ elongation

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Neural Regeneration Research 2024年第7期19卷 1415-1416页

作者： chin-Tong Ong Zhen-Kai Ngian Temasek Life Sciences Laboratory and department of Biological Sciences National University of SingaporeSingaporeSingapore department of Genetics Harvard Medical SchoolBostonMAUSA Institute of Molecular and Cell Biology Agency for ScienceTechnology and ResearchSingaporeSingapore

Epigenetic regulation of aging:Aging is defined as the gradual decline of physiological function and cellular integrity,causing o rganismal vulnerability to age-onset diseases and *** in different animal models have l... 详细信息

关键词： aging twelve integrity

Interaction between hydrogen sulfide/cystathionine γ-lyase and carbon monoxide/heme oxygenase pathways in aortic smooth muscle cells

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Acta Pharmacologica Sinica 2006年第12期27卷 1561-1566页

作者： Hong-fang JIN~2.Jun-bao DU~(2.4)Xiao-hui LI~2.Yan-fei WANG~2.Yin-fang LIANG~2.Chao-shu TANG~3 2.department of Pediatrics,peking {2. First Hospital,Beijing 100034,china 3 Institute of Cardiovascular Research,peking {2. First Hospital,Beijing 100034,china department of Pediatrics Peking University First Hospital Beijing 100034 China Institute of Cardiovascular Research Peking University First Hospital Beijing 100034 China

Aim:To investigate the interaction between hydrogen sulfide（H2.）/cystathion-ine γ-lyase（CSE）and carbon monoxide（CO）/heme oxygenase（HO）pathways inaortic smooth muscle cells（ASMC）.Methods:The ASMCs were divided into thefollowing groups:（1）the control group;（2.the zinc protoporphyrin（ZnPP）2.μmol/L group;（3）the propargylglycine（PPG）2.mmol/L,4 mmol/L and 10 mmol/Lgroups;and（4）the sodium hydrosulfide（NariS）1×10-5mol/L,1×10-4mol/L and1×10-3mol/L *** of the groups was further divided into 6h,12.,18hand 2.h *** CO level,represented by carboxyhemoglobin（HbCO）content was measured using a spectrophotometric method and H2. content wasdetected by a sensitive electrode *** and HO-1 expressions were de-tected by Western ***:The H2. content in the medium and CSEexpression by ASMC were markedly increased by ZnPP compared with the con-trol *** content in the medium and HO-1 expression by the ASMCstarted strengthening following 2.h treatment with PPG at 2.mmol/L,but werefurther strengthened following 18h and 2.h treatment with PPG at 4 mmol/Lcompared with the controls（P2. ***,NariS at 1×10-5mol/L and 1×10-4mol/Ldecreased the HbCO level in the medium and HO-1 expression by the ASMC after6h and 12. treatment,while NariS at 1×10-3mol/L decreased them at all timepoints of the ***:The results suggested that endogenousCO/HO and H2./CSE pathways inhibited each other in ASMC under physiologi-cal conditions.

关键词： hydrogen sulfide cystathionine γ-lyase carbon monoxide heme oxygenase

Theoretical study on the reaction mechanism of (CH3)3CO(.) radical with NO

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Science china Chemistry 2004年第4期47卷 289-294页

作者： ZHAO Hongmei1,2. LIU Kun1, SUN Chengke1 & LI Zonghe1 1. department of Chemistry, Beijing Normal university, Beijing 100875,{2.a 2. department of Chemistry, Beihua university, Jilin 132.13,{2.a 1. department of Chemistry Beijing Normal University 100875 Beijing China 2. department of Chemistry Beihua University 132013 Jilin China

The reaction mechanism of (CH3)3CO? radical with NO is theoretically investigated at the B3LYP/6-31G* level. The results show that the reaction is multi-channel in the single state and triplet state. The potential energy surfaces of reaction paths in the single state are lower than that in the triple state. The balance reaction: (CH3)3CONO(CH3)3CO?+NO, whose potential energy surface is the lowest in all the reaction paths, makes the probability of measuring (CH3)3CO? radical increase. So NO may be considered as a stabilizing reagent for the (CH3)3CO? radical.

关键词： (CH3)3CO. radical DFT reaction mechanism NO

A new sequential learning algorithm for RBF neural networks

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Science china(Technological Sciences) 2004年第4期47卷 447-460页

作者： YANG Ge1, LV Jianhong1 & LIU Zhiyuan2.1. department of Power Engineering, Southeast university, Nanjing 2.0096,{2.a 2. department of Power Engineering, Nanjing Institute of Technology, Nanjing 2.0013,{2.a 1. department of Power Engineering Southeast University 210096 Nanjing China 2. department of Power Engineering Nanjing Institute of Technology 210013 Nanjing China

Due to their inherent imperfections, it is hard to use the static neural networks for nonlinear time-varying process modeling and prediction, and the minimal resource allocation network (MRAN) is difficult to be realized for its too many regulation parameters. A new sequential learning algorithm for radial basis function (RBF) neural networks based on local projection named Local Projection Network (LPN) is proposed in this paper. The results of validation for several benchmark problems with the new algorithm show that the presented LPN not only has the same level as M-RAN in network size and precision of the outputs, but also has fewer regulation parameters and is more predictable.

关键词： radial basis functions, local projection network, minimal resource allocation network, learning algorithm.

CONVERGENCE OF CHORIN-MARSDEN FOR MULA FOR THENAVIER-STOKES EQUATIONS ON CONVEX DOMAINS

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Journal of Computational Mathematics 1999年第1期17卷 73-88页

作者： Lung-an Ying(Research institute for Mathematical Sciences, Kyoto university, Japan department of Mathematics,{2., Beijing 100871, china) peking Univ Dept Math Beijing 100871 Peoples R China Kyoto Univ Math Sci Res Inst Kyoto Japan

We prove the convergence of the Chorin-Marsden product formula for solving the initial-boundary value problems of the Navier-Stokes equations on convex domains. As a particular case we consider the case of the half pl... 详细信息

关键词： Navier Stokes equation vortex method fractional step method convergence

Estimating surface evapotranspiration using combined MODIS and CBERS-02.data

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Science china(Technological Sciences) 2005年第S2期48卷 145-160页

作者： XIN Xiaozhou1,2. LIU Qinhuo1, TANG Yong1,3, TIAN Guoliang1, GU Xingfa1, LI Xiaowen1,2. ZHENG Hongsheng4 & CHEN Jiayi4 1. State Key Laboratory of Remote Sensing Science, Institute of Remote Sensing Applications, chinese Academy of Sciences, Beijing 100101, china 2. Research Center for Remote Sensing and GIS, {2. of Geography, Beijing Normal university, Beijing 100875, china 3. Graduate university of chinese Academy of Sciences, Beijing 100039, china 4. {2. of Atmospheric Physics, peking university, Beijing 100871, china 1. State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences 100101 Beijing China2. Research Center for Remote Sensing and GIS Department of Geography Beijing Normal University 100875 Beijing China3. Graduate University of Chinese Academy of Sciences 100039 Beijing China4. Department of Atmospheric Physics Peking University 100871 Beijing China

Spatial scale error is one of the most serious problems in the estimates of land surface heat fluxes of sensible and latent from satellite-borne data such as MODIS 1km resolution reflectance and emissive data. One of the feasible and economic ways to decrease the spatial scale error is to use high resolution land use class data together with the MODIS data. CBERS-02.data were used to produce land use class of Baiyangdian area, Hebei Province, china in the autumn of 2.04. The area ratio of each class in MODIS pixel was calculated, and used to derive the heat fluxes of the mixed pixel. The results showed that the estimated heat fluxes of soil, sensible and latent have been changed remarkably after using the high resolution land class data. It could be concluded from the comparison between simulated and ground-measured fluxes as well as the theoretical analysis that high resolution land class data are useful to diminishing the scale error of heat fluxes estimated from low resolution satellite data.

关键词： surface evapotranspiration spatial scale error MODIS CBERS land class.

Steady States of Some Models for Van derWaals Fluids

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Communications in Nonlinear Science and Numerical Simulation 1998年第3期3卷 163-167页

作者： Shaoqiang TANG(department of Mechanics and Engineering Science, peking university, Beijing {2.,china) department of Mechanics and Engineering Science Peking University Beijing 100871 China

We study the steady states of some models for van der Waals fluid. Inparticular, for a mass viscosity model, we show that there is no "cavitation’ wave. Wealso consider the closed orbits, heterocliaic orbits, and the... 详细信息

关键词： steady state phase transition mixed-type problem