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Topological Approach to the Study of Global Stationary Property of Quantum Systems

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Chinese Physics Letters 1999年第2期16卷 82-84页

作者： XU Gong-ou xing yong-zhong YANG Ya-tian Department of Physics Nanjing UniversityNanjing 210093 Department of Physics fujian Normal Universityfuzhou 350007

A topological approach to the study of global stationary property of quantum systems is carefully *** attentions are paid to basic notions such as homeomorphic map,topological-structure-preserving(TSP)map,and bifurcat... 详细信息

关键词： topological Stationary bifurcation

General Character of Quantum Regular Motion and Quantum-Classical Correspondence

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Chinese Physics Letters 1999年第5期16卷 318-320页

作者： XU Gong-ou YANG Ya-tian xing yong-zhong Department of Physics Nanjing UniversityNanjing 210093 Department of Physics Fujian Normal UniversityFuzhou 350007

In order to have a complete description of the spatio-temporal evolution of a quantum state,the initial state should be properly specified as the coherent state corresponding to a definite dynamical *** we have qualitatively different situations where the initial coherent state evolves under the action of a system having or not having the same dynamical *** the former case,we have regular motion with the general character which tends to that of the corresponding classical case in the limit n→*** in the latter case,we may have energy regions of global stochasticity with characters closely related to the initial dynamical symmetry strongly violated.

关键词： dynamical coherent Regular

The CCT domain-containing gene family has large impacts on heading date, regional adaptation, and grain yield in rice

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Journal of Integrative Agriculture 2017年第12期16卷 2686-2697页

作者： ZHANG Jia HU yong XU Li-he HE Qin FAN Xiao-wei xing yong-zhong National Key Laboratory of Crop Genetic Improvement/Hubei Collaborative Innovation Center for Grain Industry HuazhongAgricultural University Wuhan 430070 P.R. China

There are 41 members of the CCT（CO, CO-like, and TOC1） domain-containing gene family in rice, which are divided into three subfamilies： COL（CONSTANS-like）, CMF（CCT motif family）, and PRR（pseudoresponse regulator）. The first flowering gene to be isolated by map-based cloning, Heading date 1（Hd1）, which is the orthologue of CO in rice, belongs to COL. The central regulator of plant development, Ghd7, belongs to CMF. The major role in controlling rice distribution to high latitudes, Ghd7.1/PRR37, belongs to PRR. Both of Hd1, Ghd7 and Ghd7.1 simultaneously control grain number, plant height, and the heading date. To date, 13 CCT family genes from these three subfamilies have been shown to regulate flowering. Some of them have pleiotropic effects on grain yield, plant height, and abiotic stresses, and others function as circadian oscillators. There are two independent photoperiod flowering pathways that are mediated by GI-Hd1-Hd3 a/RFT and GI-Ehd1-Hd3 a/RFT in rice. CCT family genes are involved in both pathways. The latest study reveals that protein interaction between Hd1 and Ghd7 integrates the two pathways. CCT family genes are rich in natural variation because rice cultivars have been subjected to natural and artificial selection for different day lengths in the process of domestication and improvement. Alleles of several crucial CCT family genes such as Hd1, Ghd7, and Ghd7.1 exhibit geographic distribution patterns and are highly associated with yield potentials. In addition, CCT family genes are probably involved in the responses to abiotic stress, which should be emphasized in future work. In general, CCT family genes play important roles in regulating flowering, plant growth, and grain yield. The functional identification and elucidation of the molecular mechanisms of CCT family genes would help construct a flowering regulatory network and maximize their contribution to rice production.

关键词： photoperiod sensitivity protein interaction yield potential geographic distribution abiotic stress

Dynamical-Symmetry Breaking, Mechanism and Characterization Behaviour

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Chinese Physics Letters 2001年第5期18卷 625-627页

作者： XU Gong-Ou XU Ming-Jie xing yong-zhong YANG Ya-Tian Department of Physics Nanjing UniversityNanjing 210093 Department of Geoscience Nanjing UniversityNanjing 210093 Center of Theoretical Nuclear Physics National Laboratory of Heavy-Ion AcceleratorLanzhou 730000 Institute of Theoretical Physics Chinese Academy of SciencesBeijing 10008 Department of Physics Fujian Normal UniversityFuzhou 350007 Department of Physics Tianshui Normal CollegeTianshui 741000

The integrability of quantum systems is charactized by the algebraic notion of dynamical symmetry,hence the nonintegrability of quantum systems should be discussed topologically in reference to corresponding integrable ones.A topological approach is *** topological map in general is shown to be constituted of the piecewise diffeomorphic maps interrupted by sudden nondiffeomorphic maps and thus has the similar typical feature of stretching-folding stretching......as the Smale horse-shoe map.

关键词： topological stretching integrable

Sigma Meson Production in Nuclear Reactions

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Communications in Theoretical Physics 2008年第9期50卷 725-728页

作者： ZHENG Yu-Ming FUCHS C. SRISAWAS Pornrad FAESSLER Amand YAN Yu-Peng KOBDAJ Chinorat xing yong-zhong China Institute of Atomic Energy P.O. Box 275（18） Beijing 102413 China Institute of Basic Physics School of Mathematics-Physics and Information Tianshui Normal University Tianshui 741000 China Institut für Theoretische Physik der Universitaet Tfibingen Auf der Morgenstelle 14 D-72076 Tübingen Germany Department of Physics Faculty of Science Naresuan University Amphoe Mueany Phitsanulok 65000 Thailand School of Physics Institute of Science Suranaree University of Technology Nakhon Ratchasima 30000 Thailand

The sigma meson production in p ＋ ^12C and p A- ^40Ca reactions at the incident energy Ep = 1.5 GeV is investigated within the Quantum Molecular Dynamics model. The simulation results indicate a distinctive A dependence of the sigma production, that is, the increase of A is followed by an increase of the production cross sections. We find that the σ meson production in proton-induced reactions is strongly medium-dependent, and the produced σ mesons decaying in a denser medium experience a stronger mass shift towards lower masses. This mass shift is an experimentally accessible observable in the final state pion pairs, which do not suffer from reabsorption by the surrounding nucleons. It is pointed out that the ratio of measured sigma cross sections as a function of the sigma invariant-mass from various reactions is a good probe to explore the existence of the σ meson in a dense nuclear environment.

关键词： sigma meson production medium modification the invariant-mass distribution nuclear reaction quantum molecular dynamics model

Investigation of gravity influence on EOR and CO_(2) geological storage based on pore-scale simulation

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Petroleum Science 2024年第2期21卷 987-1001页

作者： yong-Mao Hao Gui-Cheng Wu Zong-Fa Li zhong-Hui Wu yong-Quan Sun Ran Liu xing-xing Li Bo-Xin Pang Nan Li Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)) Ministry of EducationQingdao266580ShandongChina School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina School of Petroleum Engineering Yangtze UniversityWuhan430100HubeiChina Dongsheng Jinggong Petroleum Development Group Co. LtdShengli Oilfield CompanySINOPECDongying257001ShandongChina

Gravity assistance is a critical factor influencing CO_(2)-Oil mixing and miscible flow during EOR and CO_(2)geological *** on the Navier-Stokes equation,component mass conservation equation,and fluid property-composition relationship,a mathematical model for pore-scale CO_(2) injection in oilsaturated porous media was developed in this *** model can reflect the effects of gravity assistance,component diffusion,fluid density variation,and velocity change on EOR and CO_(2) *** nonhomogeneous porous media,the gravity influence and large density difference help to minimize the velocity difference between the main flow path and the surrounding area,thus improving the oil recovery and CO_(2) *** CO_(2) injection angles and oil-CO_(2) density differences can increase the oil recovery by 22.6% and 4.2%,respectively,and increase CO_(2) storage by 37.9% and 4.7%,*** diffusion facilitates the transportation of the oil components from the low-velocity region to the main flow path,thereby reducing the oil/CO_(2) concentration difference within the porous *** diffusion can increase oil recovery and CO_(2) storage by 5.7% and 6.9%,*** addition,combined with the component diffusion,a low CO_(2) injection rate creates a more uniform spatial distribution of the oil/CO_(2) component,resulting in increases of 9.5% oil recovery and 15.7% CO_(2) storage,*** study provides theoretical support for improving the geological CO_(2) storage and EOR processes.

关键词： Gravity Flow simulation CO_(2)-oil mixing Enhanced oil recovery(EOR) Geological storage

Research on the influences of motion characteristics of jetting projectile charge under water

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Defence Technology（防务技术） 2024年第3期33卷 411-425页

作者： xing Chen yong-gang Lu Institute of Systems Engineering China Academy of Engineering PhysicsMianyang 621900SichuanChina

Shaped charge warhead is important for enhancing the damage performance of underwater *** paper used finite element analysis software and based on JPC water penetration experiments to examine the influence of liner parameters(wall thickness,material),charge aspect ratio,and stand-off distance on the movement characteristics of JPC in *** findings reveal that the head diameter of the JPC increases and experiences significant erosion after entering the water,the effective length of the JPC in water undergoes two distinct phases:a growth phase and a decrease phase,with the velocity of the JPC decaying *** the liner thickness,stand-off distance and the charge aspect ratio can improve the erosion resistance and the velocity retention capacity of the *** optimal ranges for liner thickness and stand-off distance are 0.0363D_(k) to 0.0545D_(k)(D_(k) is the charge diameter),the stand-off distance should be within 1.0D_(k).After the charge aspect ratio higher than 1.25,the charge structure exerts minimal influence the movement characteristics of the JPC in *** density plays a crucial role in the velocity decay pattern of the JPC during *** with higher densities exhibit superior velocity retention capabilities in water,with the velocity decay pattern converging if the densities are ***,copper,tantalum and tungsten liners are deemed appropriate for underwater shaped charge ***,the results will provide an important reference for the design of underwater shaped charge warhead.

关键词： JPC Movement characteristics Underwater penetration Numerical simulation

Miniaturized power detection module operating in millimeter wave band

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Journal of Electronic Science and Technology 2024年第2期22卷 69-76页

作者： Xiang Zhou Zhi-yong zhong School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China

The miniaturized broadband detection module can be embedded into the microwave application system such as the front end of the transmitter to detect the power or other parameters in real *** is highly prospective in military and scientific *** this paper,a broadband power detection module operating at 26.5 GHz-40.0 GHz is designed by using low-barrier Schottky diode as the detector and a comparator for threshold *** module can dynamically detect the power range between-10 dBm and 10 dBm with the detection accuracy of 0.1 ***,the temperature compensation circuit is also applied to improve the measurement *** a result,the resulted error low to±1 dB in the temperature range of -55℃ to +85℃ is *** designed module is encapsulated by a Kovar alloy with a small volume of 9 mm×6 mm×3 *** endows the designed module the advantages of small size,easy integration,and low cost,and even it is applicable to high-reliability environments such as satellites.

关键词： Diode Miniaturization Power detection Temperature compensation

不变振幅的不同投影选择对核子自能与碰撞截面的影响

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物理学报 2014年第15期63卷 53-60页

作者：邢永忠赵兴文郑玉明天水师范学院基础物理学研究所天水741000 西北师范大学物理与电子工程学院兰州730070 中国原子能科学研究院北京102413

本文利用Dirac-Brueckner-Hartree-Fock方法,对不同散射道的核子在核物质中的相互作用进行了细致分析,重点分析了不变振幅的不同投影选择对核物质中核子自能和核子碰撞截面的影响.计算结果显示:1)在确定的核子动量下,自旋三重态所对应... 详细信息

本文利用Dirac-Brueckner-Hartree-Fock方法,对不同散射道的核子在核物质中的相互作用进行了细致分析,重点分析了不变振幅的不同投影选择对核物质中核子自能和核子碰撞截面的影响.计算结果显示:1)在确定的核子动量下,自旋三重态所对应的自能总是大于自旋单态的自能;同位旋三重态所对应的自能大于同位旋单态的自能值.2)在完全赝矢(CPV)选择下,不同散射道的核子自能对于动量的依赖均明显弱于在赝标(PS)选择下的相应值,而这种差别主要来自于总角动量J较小的分波态.3)在核子相对动量较小时,两种不同选择所对应的核子微分截面较大.4)在确定的入射能量下,质心系中散射角较小时,不同选择下的微分截面差别较为明显.5)在低入射能区,CPV选择下所对应的微分截面大于PS下的微分截面值.6)在CPV选择下的总截面总是大于PS选择下的总截面值.这些差别均随着随入射能量的增大而消失.

关键词：自能截面不变振幅投影相对论Brueckner方法