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Cal.ulation of f_(σ) on Quark level

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Chinese Physics letters 1996年第9期13卷 652-655页

作者： lÜXiao-fu l.u yu-xin ZHAO En-guang Department of Physics Sichuan UniversityChengdu 610064 Department of Physics Peking UniversityBeijing 100871 Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100080

With the recently obtained vacuum configuration of the bilocal field,we have cal.ulated the decay constant f_(σ) of σ-meson in a quantum chromodynamics-based model field *** investigating the cal.ulated result,it ca... 详细信息

关键词： theory decay meson

Ab Initio Study on The Influence of Spin State upon Bonding and Interaction in FeCO*

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Chemical Research in Chinese universities 1999年第2期15卷 71-81页

作者： Xu xin l xin XIAN Hui CAI yu WANG Nanqin ZHANG Qianer State Key laboratory for Physical Chemistry of Solid Surface Institute of Physical ChemistryDepartment of ChemistryXiamen UniversityXiamen361005

Four FeCO states with 3d4s and 3d3d electrons spinpaired or spinunpaired were examined to investigate the influences of pairing versus unpairing mechanisms upon the bonding and interaction in *** cal.ulation results show that the FeCO bonding and interaction are determined by a balance between the bonding stabilization and the exchange stabilization with 3d4s electron spinpairing or without *** 3d3d electron spinpairing versus unpairing has a surprised effect on the FeCO bonding properties even though the 3d orbitals are usually considered as non bonding ones.

关键词： Ab initio Carbon monoxide Iron Transitionmetal carbonyl Bonding mechanism

Measurements of non-equilibrium and equilibrium temperature behind a strong shock wave in simulated martian atmosphere

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Acta Mechanica Sinica 2012年第5期28卷 1296-1302页

作者： xin lin Xi-long yu Fei li Shao-Hua Zhang Jian-Guo xin xin-yu Zhang School of Optoelectronics Beijing Institute of Technology State Key laboratory of High Temperature Gas Dynamics Institute of MechanicsChinese Academy of Sciences

Non-equilibrium radiation measurements behind strong shock wave for simulated Martian atmosphere are presented in this paper. The shock wave is established in a hydrogen oxygen combustion driven shock tube. Time- resolved spectra of the Av = 0 sequence of the B^2∑^＋ → X^2∑^＋ electronic transition of CN have been observed through optical emission spectroscopy （OES）. A new method, which is based on fitting high resolution spectrum for rotational and vibrational temperatures measurement, is proposed to diag- nose temperature distribution behind the shock wave. It is estimated that the current scheme has the maximum deviation less than 8% （lσ） for vibrational temperature measurement through detailed analysis of the influence of the uncertainties of spectroscopic constants and spectral resolution. Radiation structure of the shock layer, including induction, relaxation and equilibrium process, and corresponding rotational and vibrational temperatures are obtained through time gating OES diagnostics with sub-microsecond temporal resolution. The present extensive results will strongly benefit the reaction rate estimation and computational fluid dynamics （CFD） code validation in high enthalpy Mars reentry chemistry.

关键词： Radiation measurements - Shock wave Marsre-entry Rotational temperature Vibrational temperature

Codegree Threshold for Tiling k-graphs with Two Edges Sharing Exactly l Vertices

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Acta Mathematica Sinica,English Series 2020年第1期36卷 13-20页

作者： lei yu xin Min HOu Key laboratory of Wu Wen-Tsun Mathematics School of Mathematical Sciences University of Science and Technology of China

Given integer k and a k-graph F,let t(k-1)(n,F)be the minimum integer t such that every k-graph H on n vertices with codegree at least t contains an *** integers k>3 and 0≤l≤k-1,let y(k,l)be a k-graph with two edges that shares exactly l *** and Zhao(*** Ser.A,(2015))asked the following question:For all k≥3,0≤l≤k-1 and sufficiently large n divisible by 2 k-l,determine the exact value of t_(k-1)(n,y(k,l)).In this paper,we show that t(k-1)(n,y(k,l))=n/(2 k-l)for k>3 and 1≤l≤k-2,combining with two previously known results of R?dl,Rucinski and Szemeredi(*** Ser.A,(2009))and Gao,Han and Zhao(Combinatorics,Probability and Computing,(2019)),the question of Han and Zhao is solved completely.

关键词： Hypergraph codegree factor

STABIlITY ANAlYSIS OF RuNGE-KuTTA METHODS FOR NONlINEAR SYSTEMS OF PANTOGRAPH EQuATIONS

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Journal of Computational Mathematics 2005年第4期23卷 351-356页

作者： yue-xin yu Shou-fu li Department of Mathematics Xiangtan University Xiangtan 411105 China

This paper is concerned with numerical stability of nonlinear systems of pantograph equations. Numerical methods based on （k, l）-algebraically stable Runge-Kutta methods are suggested. Global and asymptotic stabilit... 详细信息

关键词： Nonlinear pantograph equations Runge-Kutta methods Numerical stability Asymptotic stability

Historical Sediment Record of ^(137)Cs, δ-HCH, and δ^(13)C Reflects the Impact of land use on Soil Erosion

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Journal of Mountain Science 2014年第4期11卷 866-874页

作者： TANG Xiang-yu ZHANG xin-Bao GuAN Zhuo lONG Yi TANG Qiang lü yu-Juan Key laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and Environment Chinese Academy of Sciences College of Water Resources and Architectural Engineering Northwest A&F University

This paper reports the concentrations of 137Cs, hexaehlorocyclohexane （HCH）, dichlorodiphenyltrichloroethanes （DDT） and its main degradation products, δ3C, and organic carbon in pond sediments （O-210 cm, sectioned by 2-20 cm interval） and surface soils （the 0-3 cm horizon） collected in 2OlO from Chenjia catchment, which is located in Yanting county in the hilly central Sichuan of China. α-, β-, and γ-HCH, DDT, and DDD were not detected throughout the sediment profile. Trace concentrations of δ-HCH （0.89-29.31 ng g^-1） and p,p＇- DDE （1.85-6.02 ng g^-1） were detected only in top 40 cm sediment. The 137Cs fall.ut peak in 1963 （corresponding to the 55-60 cm depth）, the sedimentary signature left by the last year of HCH use in 1989 （an additional indicator at 20-25 cm）, and the obvious original channel bed prior to the construction of the pond in 1956 were used as temporal markers to estimate changes in average sedimentation rate between different periods due to changes in land use. Continuous, marked decrease in average sedimentation rate （i.e., 3.79, 1.35 and 1.07 cm year-1 in 1956-1963, 1963-1989, and 1989-2010, respectively） over time was observed, probably due to the reforestation, abandoning of steep sloping farmland for afforestation and natural re-vegetation （implementation of the Grain for Green Program）, and the conversion of part of gently sloping farmlandterraces to orchard land since the 1980s, especially since the 1990s. This was corroborated by the observed decrease （more negative） in δ3C of sediment towards the surface, which indicates increased relative contribution of eroded soil particles coming from slopes with increased tree cover in sediment source area. Combined use of 137Cs, δ-HCH, and δ3C record in sediments has been demonstrated to be a powerful approach to reconstruction of response in sedimentation rate to historical land use changes.

关键词： Cesium-137 Hexaehlorocyclohexane(HCH) Sedimentation history land use

Sn/n3O4-x heterostructure rich in oxygen vacancies with enhanced visible light photocatalytic oxidation performance

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International Journal of Minerals,Metal.urgy and Materials 2021年第1期28卷 150-159页

作者： Rui-qi Yang Na liang Xuan-yu Chen long-wei Wang Guo-xin Song Yan-chen Ji Na Ren Ya-wei lü Jian Zhang xin yu Institute for Advanced Interdisciplinary Research(IAIR) University of JinanJinan 250022China School of physics and electronics Hunan UniversityChangsha 410082China Institute Charles Gerhardt UMR 5253CNRS-UM-ENSCMUniversitéde MontpellierPlace Eugène BataillonF-34095 Montpellier cedex 5France

Sn3O4, a common two-dimensional semiconductor photocatalyst, can absorb visible ***, owing to its rapid recombination of photogenerated electron-hole pairs, its absorption is not sufficient for practical *** this work, a Sn nanoparticle/Sn3O4-x nanosheet heterostructure was prepared by in situ reduction of Sn3O4 under a H2 *** Schottky junctions formed between Sn and Sn3O4-x can enhance the photogenerated carrier separation *** the hydrogenation process, a portion of the oxygen in the semiconductor can be extracted by hydrogen to form water, resulting in an increase in oxygen vacancies in the *** heterostructure showed the ability to remove Rhodamine *** cytocompatibility experiments proved that Sn/Sn3O4-x can significantly enhance cell compatibility and reduce harm to *** work provides a new method for the fabrication of a Schottky junction composite photocatalyst rich in oxygen vacancies with enhanced photocatalytic performance.

关键词： photocatalysis tin oxide oxygen vacancy Schottky junction photodegradation

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青稞分蘖角度的QTl定位

作物学报 2025年第1期51卷 260-272页

作者：杨景发余鑫莲姚有华姚晓华王蕾吴昆仑李新青海大学农林科学院/青海省作物分子育种重点实验室/青海省青稞遗传育种重点实验室/青藏高原种质资源研究与利用实验室/青海大学省部共建三江源生态与高原农牧业国家重点实验室青海西宁810016

分蘖角度是青稞株型的主要构成因素,在提高青稞产量与抗倒伏性中发挥着极为重要的作用。为解析青稞分蘖角度的遗传机制,本研究以青稞品种‘达章紫’(株型松散)和‘昆仑10号’(株型紧凑)为亲本构建的RIl群体为材料,基于高密度遗传图谱,... 详细信息

分蘖角度是青稞株型的主要构成因素,在提高青稞产量与抗倒伏性中发挥着极为重要的作用。为解析青稞分蘖角度的遗传机制,本研究以青稞品种‘达章紫’(株型松散)和‘昆仑10号’(株型紧凑)为亲本构建的RIl群体为材料,基于高密度遗传图谱,在多环境中进行青稞分蘖角度的QTl定位,并利用RIl群体衍生的剩余杂合系,对鉴定到的主效QTlqTA7H-1进行精细定位。在青稞7条染色体上共检测到9个控制分蘖角度的QTl,解释表型变异为6.41%~33.57%,其中,qTA3H-1和qTA7H-1为多环境共检测的主效QTl,平均加性效应分别为5.42°(增效)和-3.87°(减效);在减效QTl qTA7H-1初定位区间筛选到4个剩余杂合体,自交衍生F8:9近等基因系,在置信区间内加密设计14对分子标记对RHl群体极端单株进行检测,利用获得的5种交换类型单株,将qTA7H-1进一步界定在PC08(32,252,397)与PA10(41,790,765)约9.54Mb的物理区间内。本研究初步揭示调控青稞分蘖角度的遗传因子,为开展分蘖角度性状的遗传改良与分子设计育种奠定了基础。

关键词：青稞分蘖角度 QTl定位主效位点

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Dissipation-Driven Superradiant Phase Transition of a Two-Dimensional Bose-Einstein Condensate in a Double Cavity

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Chinese Physics letters 2024年第6期41卷 44-48页

作者： Bo-Hao Wu xin-xin Yang yu Chen Wei Zhang Department of Physics and Beijing Key laboratory of Opto-electronic Functional Materials and Micro-nano Devices Renmin University of ChinaBeijing 100872China Key laboratory of Quantum State Construction and Manipulation(Ministry of Education) Renmin University of ChinaBeijing 100872China Graduate School of China Academy of Engineering Physics Beijing 100193China Beijing Academy of Quantum Information Sciences Beijing 100193China

We study superradiant phase transitions in a hybrid system of a two-dimensional Bose–Einstein condensate of atoms and two cavities arranged with a tilt *** adjusting the loss rate of cavities,we map out the phase diagram of steady states within a mean field *** is found that when the loss rates of the two cavities are different,superradiant transitions may not occur at the same time in the two cavities.A first-order phase transition is observed between the states with only one cavity in superradiance and both in *** the case that both cavities are superradiant,a net photon current is observed flowing from the cavity with small decay rate to the one with large decay *** photon current shows a non-monotonic dependence on the loss rate difference,owing to the competition of photon number difference and cavity field phase *** findings can be realized and detected in experiments.

关键词： Einstein transitions decay