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Strong decays of N~*(1535) in an extended chiral quark model

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Science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1452-1457页

作者： AN ChunSheng1,2.3 & ZOU BingSong1,2.3 1 institute of High energy Physics,Chinese Academy of Sciences,{2. 100049,china 2.Theoretical Physics Center for Science Facilities,Chinese Academy of Sciences,{2. 100049,china 3 Graduate University of Chinese Academy of Sciences,{2. 100049,china institute of High energy Physics Chinese Academy of Sciences Beijing 100049 China Theoretical Physics Center for Science Facilities Chinese Academy of Sciences Beijing 100049 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

The strong decays of the N*(1535) resonance are investigated in an extended chiral quark model by including the low-lying $ qqqq\bar q $ components in addition to the qqq component. The results show that these five-quark components in N*(1535) contribute significantly to the N*(1535) → Nπ and N*(1535) → Nη decays. The contributions to the Nη decay come from both the lowest energy and the next-tolowest energy five-quarks components, while the contributions to the Nπ decay come from only the latter one. Taking these contributions into account, the description for the strong decays of N*(1535) is improved, especially for the puzzling large ratio of the decays to Nη and Nπ.

关键词： N*(1535) strong decays five-quark components

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整合医学宣言

肿瘤药学 2024年第4期14卷 393-395页

作者： china institute for Development Strategy of Holistic Integrative Medicine 中国整合医学发展战略研究院

整体整合医学简称整合医学，自2.12.正式提出，其理论体系不断完善，实践方法日趋丰富，成为医学发展新时代的必然选择和必由之路。本文提出整合医学的十大主张，从认识论和方法学上阐述了整合医学的内涵和外延，以期实现现代医学的升... 详细信息

整体整合医学简称整合医学，自2.12.正式提出，其理论体系不断完善，实践方法日趋丰富，成为医学发展新时代的必然选择和必由之路。本文提出整合医学的十大主张，从认识论和方法学上阐述了整合医学的内涵和外延，以期实现现代医学的升维转型和自适应进化。

关键词：整体整合医学整合医学医学发展

Case studies on mesoscale structures of heavy rainfall system in the Yangtze River generated by Meiyu front

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Science china Earth Sciences 2005年第8期48卷 1303-1311页

作者： LIU Liping1, RUAN Zheng1 & QIN Danyu2.1. Chinese Academy of Meteorological Sciences, beijing 100081, china 2. Nanjing {2. of Meteorology, Nanjing 2.0044, china 1. Chinese Academy of Meteorological Sciences 100081 Beijing China 2. Nanjing institute of Meteorology 210044 Nanjing China

A heavy rainfall system was observed over the Yangtze River during Meiyu season by using dual-Doppler radar systems in the field experiment conducted by the project of National Fundamental Research Planning “Research on formation mechanism and the prediction theory of hazardous weather over china”. The three-dimensional mesoscale kinematic structure and process of a heavy rain on 2. and 2. July, 2.02.are investigated by using the radial velocity and dual-Doppler radar technique. The results show that a southwest-northeast oriented rain band with the length of about 1000 km involves numbers of meso-β or meso-γ-scale convective cells with the size of 2.―50 km. The heavy rain band in the middle reaches of the Yangtze River ex-ists in a low-level wind shear. The interaction between southwest low-level jet on the southern side of wind shear and east wind on the northern side formed the updraft. The wind disturbance, wind shear and convergence generate the convective action. The new cell developed in right rear flank of rain band and moved to the southwest wind area, where the vapor is abundant. This kind of echo can last a long time and developed well. The strong convective echoes are often ac-companied by the meso-γ-scale vortex and convergence.

关键词： heavy rainfall in Meiyu front, mesoscale structure, dual-Doppler radar, middle reaches of the Yangtze River, low-level jet.

Effect of Manganese substitution on hydrogen storage properties of LaNi_(4.2.-x)Al_(0.75)Mn_(x) alloy

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Rare Metals 2006年第z2期25卷 204-208页

作者： JIANG Yuwei LIU Xiaopeng JIANG Lijun WANG Shumao YANG Hongguang institute for energy Materials and Technology General Research Institute for Non-ferrous MetalsBeijing 100088China china institute of {2. energy Beijing 102413China

The effect of Mn substitution on phase structure,hydrogen hydriding/dehydriding properties(plateau pressure and slope)and reaction heat enthalpy of LaNi_(4.2.-x)Al_(0.75)Mn_(x)alloys(x=0,0.2.,0.35,0.45,0.55 and 0.65)were *** experimental results show that all LaNi_(4.2.-x)Al_(0.75)Mn_(x)alloys have single phase and have the same hexagonal structure as that of LaNi5 alloy(CaCu_(5)type,P6/mmm).With increasing Mn substitution content,the cell parameters of LaNi_(4.2.-x)Al_(0.75)Mn_(x)alloy greatly increase,but the maximum hydrogen storage capacity and the equilibrium absorption pressure of LaNi_(4.2.-x)Al_(0.75)Mn_(x)alloy decrease from 1.38 wt.%to 1.18 wt.%and from 1.61 to 0.0712.MPa,***,the hydrogen pressure plateau slope factorσincreases from 0.014 to 0.18,but the hysteresis factor is nearly *** heat enthalpy absolute value|ΔH_(plat)|increases from 46.7 kJ·mol^(-1)H2.to 56.1 kJ·mol^(-1)H_(2.as the Mn content x increases from 0 to 0.65.

关键词： hydrogen storage alloy La-Ni-Al-Mn alloy P-C-T hysteresis and plateau slope

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《整合医学宣言》

广州中医药大学学报 2024年第10期41卷 2515-2517页

作者： china institute for Development Strategy of Holistic Integrative Medicine 中国整合医学发展战略研究院

整体整合医学简称整合医学，自2.12.正式提出以来，其理论体系不断完善，实践方法日趋丰富，成为医学发展新时代的必然选择和必由之路。该文提出整合医学的十大主张，从认识论和方法学上阐述了整合医学的内涵和外延，以期实现现代医学... 详细信息

整体整合医学简称整合医学，自2.12.正式提出以来，其理论体系不断完善，实践方法日趋丰富，成为医学发展新时代的必然选择和必由之路。该文提出整合医学的十大主张，从认识论和方法学上阐述了整合医学的内涵和外延，以期实现现代医学的升维转型和自适应进化。

关键词：整体整合医学整合医学医学发展

Prediction of Dynamic Wellbore Pressure in Gasified Fluid Drilling

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Petroleum Science 2007年第4期4卷 66-73页

作者： Wang Zhiming1,Ping Liqiu2.and Zou Ke2.(1. School of Petroleum Engineering,Petroleum University of china,beijing 102.49,china) (2. institute of Drilling Engineering Technology,CNPC,beijing 100097,china) Petr Univ china Sch Petr Engn Beijing 102249 Peoples R China CNPC Inst Drilling Engn Technol Beijing 100097 Peoples R China

The basis of designing gasified drilling is to understand the behavior of gas/liquid two-phase flow in the wellbore. The equations of mass and momentum conservation and equation of fluid flow in porous media were used to establish a dynamic model to predict wellbore pressure according to the study results of Ansari and Beggs-Brill on gas-liquid two-phase flow. The dynamic model was solved by the finite difference approach combined with the mechanistic steady state model. The mechanistic dynamic model was numerically implemented into a FORTRAN 90 computer program and could simulate the coupled flow of fluid in wellbore and reservoir. The dynamic model revealed the effects of wellhead back pressure and injection rate of gas/liquid on bottomhole pressure. The model was validated against full-scale experimental data,and its 5.0% of average relative error could satisfy the accuracy requirements in engineering design.

关键词： Gasified fluid drilling dynamic model pressure prediction model validation

Algebraically explicit analytical solu-tions for the unsteady non-Newtonian swirling flow in an annular pipe

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Science china(Physics,Mechanics & Astronomy) 2006年第4期49卷 396-400页

作者： CAI Ruixian1 & GOU Chenhua1,2.1. institute of Engineering Thermophysics, Chinese Academy of Sciences, beijing 100080, {2. 2. Graduate School, Chinese Academy of Sciences, beijing 100080, {2. 1. institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100080 China 2. Graduate School Chinese Academy of Sciences Beijing 100080 China

This paper presents two algebraically explicit analytical solutions for the incompressible unsteady rotational flow of Oldroyd-B type in an annular pipe. The first solution is derived with the common method of separation of variables. The second one is deduced with the method of separation of variables with addition developed in recent years. The first analytical solution is of clear physical meaning and both of them are fairly simple and valuable for the newly developing computational fluid dynamics. They can be used as the benchmark solutions to verify the applicability of the existing numerical computational methods and to inspire new differencing schemes, grid generation ways, etc. Moreover, a steady solution for the generalized second grade rheologic fluid flow is also presented. The correctness of these solutions can be easily proven by substituting them into the original governing equation.

关键词： analytical solution, Oldroyd-B type fluid, swirling flow, non-Newtonian.

Trace element geochemistry of the Lower Cambrian black rock series from northwestern Hunan, South china

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Progress in Natural Science:Materials International 2004年第1期14卷 65-71页

作者： PAN Jiayong 1,2. *, MA Dongsheng 1 and CAO Shuanglin 1,2. (1.The State Key Laboratory for Mineral Deposits Research, Nanjing University, Nanjing 2.0093, china 2. East china {2. of Technology, Fuzhou 344000, china) Nanjing Univ State Key Lab Mineral Deposit Res Nanjing 210093 Peoples R China E china Inst Technol Fuzhou 344000 Peoples R China

Samples of black rock series collected from the Lower Cambrian Niutitang Formation, northwestern Hunan Province, china, were analyzed for trace elements. The trace element geochemical characteristics of the ore layer (high enrichments of Ni, Mo, V, U, Cu, Pb, Zn, Cd, Tl and Ba; high U/Th ratios and LREE enriched patterns with positive Eu and Y anomalies) support the assumption that the Ni Mo polymetallic layer is of submarine hydrothermal origin. High field strength elements (HFSE) and lithophile elements such as Nb, Ta, Zr, Hf, Li, Be, Rb, Cs, Th and Sc are remarkably higher in the upper unit than those in the lower unit of the Niutitang Formation. These features may reflect that hydrothermal contributions were diminished, and terrigenous constituents were increased in the sediments of the upper unit of the Niutitang Formation.

关键词： black rock series Early Cambrian trace elements northwestern Hunan china

Experimental realization of quantum cryptography communication in free space

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Science china(Physics,Mechanics & Astronomy) 2005年第2期48卷 237-246页

作者： WANG Chuan1, ZHANG Jingfu1, WANG Pingxiao1, DENG Fuguo1, AI Qing1 & LONG Guilu1,2.1. Department of Physics, Key Laboratory for Quantum Information and Measurements, Tsinghua Univer- sity, beijing 100084, china 2. Center for {2. and Molecular NanoSciences, Tsinghua University, beijing 100084, china Department of Physics Key Laboratory for Quantum Information and Measurements Tsinghua University Beijing 100084 China atomic and Molecular NanoSciences Tsinghua University Beijing 100084 China

Utilizing linear optical devices, the principle of B92.quantum key distribution (QKD) protocol is demonstrated in free space with a distance of transmission of 2.2.meters. The faint laser pulses with 650 nm wavelength are used as the single photon sources. The experimental results show that the eavesdropping behavior in the signal transmission can be detected. We also discuss the problems and solutions in using the quantum cryptography communication practically. It is pointed out that one of the approaches to increasing the distance of the quantum communication is to overcome the attenuation of the single photon in transmission. This could not be solved by the use of single photon source, and new quantum communication protocols are needed to solve these problems.

关键词： quantum key distribution, free space, linear optics, faint pulses.