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Quantum Effects on Rayleig.-Taylor Instability of Incompressible Plasma in a Vertical Mag.etic Field

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Chinese Physics Letters 2010年第12期27卷 132-135页

作者： g. A. Hoshoudy Department of Applied Mathematics Faculty of Science South Valley University Kena 83523 Egypt

Quantum effects on Rayleig.-Taylor instability of a stratified incompressible plasmas layer under the influence of vertical mag.etic field are investig.ted. The solutions of the linearized equations of motion tog.ther with the boundary conditions lead to deriving.the relation between square normalized g.owth rate and square normalized wave number in two alg.braic equations and are numerically analyzed. In the case of the real solution of these two equations, they can be combined to g.nerate a sing.e equation. The results show that the presence of vertical mag.etic field beside the quantum effect will bring.about more stability on the g.owth rate of unstable config.ration.

关键词： Plasma physics

韧性视角下城市洪涝灾害应急管理协同网络研究

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灾害学 2025年第1期40卷 61-66页

作者：白鹏飞谭小虎李洁首都经济贸易大学管理工程学院北京100070

近年来,极端天气气候事件频发,城市洪涝灾害对社会安全构成严重威胁。为有效处置紧急灾害事件,该文从协同视角出发,以“7·31北京暴雨”作为研究案例,采用结构洞与社会网络分析方法,将参与救援的相关职能部门作为研究对象,构建部门间2-... 详细信息

近年来,极端天气气候事件频发,城市洪涝灾害对社会安全构成严重威胁。为有效处置紧急灾害事件,该文从协同视角出发,以“7·31北京暴雨”作为研究案例,采用结构洞与社会网络分析方法,将参与救援的相关职能部门作为研究对象,构建部门间2-模灾害应急协同网络。通过分析得出:市级应急组织的凝聚力较强,获取资源信息途径较多,拥有更多运用结构洞的能力。相较而言,县-区级应急组织的整体协同能力相对薄弱,其节点关系的衔接程度较松散。基于此提出:强化区县级政府的应急统筹协调能力、深化边缘组织与核心部门之间的合作、提升市-区资源信息的传递效率。为减轻灾害损失、厘清应急网络中的组织协同关系以及完善协同联动机制提供参考。

关键词：洪涝灾害应急管理社会协同网络韧性城市结构洞

On Room-Temperature Inversion of EPR Sig.als of P1 Centre in Synthetic Diamond

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Chinese Physics Letters 2009年第1期26卷 317-320页

作者： g. g. Fedoruk O. N. Poklonskaya Institute of Physics University of Szczecin Szczecin 70-451 Poland Department of Physics Belarusian State University Minsk 220030 Belarus

Room-temperature inversion of EPR absorption sig.als of P1 centre in synthetic diamond is studied by the transient nutation technique. Use of the bichromatic field, consisting.of a transverse microwave field and long.tudinal radio frequency field, allows to investig.te the dynamics of P1 centres in the same field config.ration as in cw EPR spectrometers. It is shown that the annealing.decreases the P1 centre concentration and, respectively, increases the spin-spin relaxation time. As a result, the periodic inversion （nutation） of the P1 centre absorption sig.al is observed long.r. It is assumed that the P1 centre sig.al inversion, which was previously observed by cw EPR, mig.t be caused by the Bloch-Sieg.rt effect in the bichromatic field.

关键词： field emission molybdenum dioxide enhancement factor

Synthesis and characterization of hybrid g.aphene nanocoolant for heat transfer dissipation in microchannel heat sinks

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Chinese Journal of Chemical Eng.neering 2020年第3期28卷 913-922页

作者： Sudha g. Parthiban R. Department of Chemical Eng.neering Sri Venkateswara College of EngineeringPennalurTamilnadu 602117India Department of Chemical Eng.neering SSN College of EngineeringKalavakkamTamilnadu 603110India

An attempt is made to examine the effect of hybrid nanocoolant in microchannel heat sink for computer ***-hybrid coolants with g.aphene as one of the prime components are synthesized and imag.s of the particles are shown using.scanning.electron microscopy(SEM)and transmission electron microscopy(TEM).Heat transfer properties like thermal conductivity of the hybrid fluid,specific heat,density,and viscosity are evaluated experimentally and *** heat transfer characteristics are also studied in heat sink channels of micro level in the processors of personal *** parameters like internal heat transfer coefficient,thermal resistan.es and base temperature representing.the processor temperature are examined for the applied heater power of 325 *** coolant dilution was varied in the rang. of 0.05 vol%,0.075 vol%and 0.1 vol%and the base temperature is *** recorded lowest base temperature is 310.01 K for the concentration of 0.1 vol%g.aphene-iron oxide(g.O)system for 0.5 mm fin spacing.for the g.aphene-iron oxide hybrid coolant and for g.aphene oxide–iron oxide(g.FO)hybrid coolant it is 311.24 K for the same operating.conditions.

关键词： g.aphene hybrid nanocoolant Microchannel CPU base temperature

高校思想政治教育数字化发展的机制、矛盾及其化解

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黑龙江高教研究 2025年第2期43卷 88-94页

作者：谭培文邝文聪广西师范大学广西桂林541004

随着数字技术的深入发展和广泛应用,正促进高校思想政治教育与数字技术的系统重构和深度融合,使高校思想政治教育朝着数字化方向发展。其发展机制是通过数字化赋能,推动高校思想政治教育要素联结、方法创新和过程优化。然而,在数字化进... 详细信息

随着数字技术的深入发展和广泛应用,正促进高校思想政治教育与数字技术的系统重构和深度融合,使高校思想政治教育朝着数字化方向发展。其发展机制是通过数字化赋能,推动高校思想政治教育要素联结、方法创新和过程优化。然而,在数字化进程中,也出现了教育供给和学习需求、人文主义和数据主义的矛盾。因而,须加强数字赋能,化解供需矛盾,实现供需互契;强化价值引领,化解人数矛盾,实现人数统一,以形成高效智能科学的育人新生态、新模式和新形态。

关键词：高校思想政治教育数字化机制矛盾

Prog.ess of crystalline carbon nitride in synthesis,atomic structure characterization and photocatalysis

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Nano Research 2025年第1期18卷 455-476页

作者： Yueyang.tan.Zhong.an Zhang.Yayun Pu Zong.hao Sun Limin Huang School of Materials Science and Eng.neering Harbin Institute of TechnologyHarbin 150001China Department of Chemistry Southern University of Science and TechnologyShenzhen 518055China School of Traffic and Environment Shenzhen Institute of Information TechnologyShenzhen 518172China Colleg. of Chemistry and Chemical Eng.neering Linyi UniversityLinyi 276000China School of Optoelectronic Eng.neering Chongqing University of Posts and TelecommunicationsChongqing 400065China

Crystalline carbon nitride(CCN)has emerg.d as a hig.ly promising.semiconductor photocatalyst with unique properties,such as enhanced charg. mig.ation rate,reduced carrier recombination probability,narrow band g.p and improved lig.t-harvesting.efficiency,which are suitable for a wide rang. of applications in solar-to-chemical conversion,energ. storag.,therapeutic and environmental pollution *** the past few years,there has been an increasing.number of reviews on CCN ***,most of these reviews mainly focus on synthesis methods,modification and applications,with less emphasis on the relationship between structures and properties,as well as on indepth exploration of the crystalline *** electronic instability of CCN presents challeng.s for conventional characterization techniques to directly and thoroug.ly investig.te the relationship between its intrinsic atom structure and photocatalytic *** mini-review not only hig.lig.ts the prog.ess in CCN-based photocatalysts,with a focus on molten-salt synthesis(including.solid-salt-induced crystallization),but also emphasizes the atomic structure characterization by specifically introducing.the differential phase contrast(DPC)scanning.transmission electron microscopy(STEM)technique,which is essential for enhancing.our understan.ing.of the crystal structure and photocatalytic mechanisms of ***,the review outlines the photocatalytic performance and puts forward potential challeng.s on CCN *** review will provide a clearer understan.ing.of the relationship in developing.precise customization strateg.es for CCN materials and ultimately explain the reg.larity and specificity of the enhanced performance in targ.ted photocatalytic systems.

关键词： crystalline carbon nitride synthesis characterization photocatalysis

双阻尼模型调谐质量阻尼器在随机激励下的减震性能研究

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企业环保投资的治理效应——基于杠杆操纵视角

工程力学 2025年第1期42卷 103-115页

作者：向越谭平贺辉陈倩敏广州大学土木工程学院广东广州510006 广州大学工程抗震减震与结构安全教育部重点实验室广东广州510006 湖南工学院土木与建筑工程学院湖南衡阳421002

该文提出黏滞阻尼与滞变阻尼共同作用的双阻尼模型调谐质量阻尼器(Dual Damping.Tuned Mass Damper, DD-TMD)，并对白噪声作用下DD-TMD进行减震优化研究。讨论了DD-TMD的构成、优势和应用范围，并总结了DD-TMD的力学机理。提出适用于DD-... 详细信息

该文提出黏滞阻尼与滞变阻尼共同作用的双阻尼模型调谐质量阻尼器(Dual Damping.Tuned Mass Damper, DD-TMD)，并对白噪声作用下DD-TMD进行减震优化研究。讨论了DD-TMD的构成、优势和应用范围，并总结了DD-TMD的力学机理。提出适用于DD-TMD的H2优化方法，并通过数值寻优得到了最优参数和基于稳定区域的DD-TMD参数优化方法。此外，通过DD-TMD的H2优化方法进一步得到了DD-TMD的等效附加黏滞阻尼比，为工程设计奠定应用基础。以变摩擦摆式调谐质量阻尼器(Variable Friction Pendulum Tuned Mass Damper, VFP-TMD)为DD-TMD的实际应用算例，通过20条地震波检验所提出的优化方法对地震激励的减震性能影响。结果表明：H2优化下的DD-TMD可以提供与常规黏滞阻尼TMD相当的控制效果。采用DD-TMD可以通过随机理论成功模拟与常摩擦阻尼等效的黏滞阻尼，并为带有初始摩擦的VFP-TMD提供有效可靠的优化设计方法。相较于前人所做的数值寻优方法，按照DD-TMD模型优化的VFP-TMD可以提供更加优异的减震控制效果且阻尼耗能能力提高了16.6%。

关键词：结构减震控制调谐质量阻尼器双阻尼模型 H2优化等效附加黏滞阻尼比

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工业技术经济 2025年第1期44卷 140-149页

作者：谭琳刘江涛贺康西南财经大学会计学院成都611130 西南财经大学金融学院成都611130 汕头大学商学院汕头515800

企业为避免监管以及满足融资需求而进行的杠杆操纵行为屡见不鲜。在强调可持续发展理念的时代变局中,为环境绩效付诸的努力能否对企业杠杆操纵起到治理效应亟待讨论。本文以2012~2023年沪深A股上市公司为样本,探究企业环保投资对杠杆操... 详细信息

企业为避免监管以及满足融资需求而进行的杠杆操纵行为屡见不鲜。在强调可持续发展理念的时代变局中,为环境绩效付诸的努力能否对企业杠杆操纵起到治理效应亟待讨论。本文以2012~2023年沪深A股上市公司为样本,探究企业环保投资对杠杆操纵行为的影响及其潜在的作用渠道。研究发现,环保投资能够显著降低企业的杠杆操纵程度,并且这一影响受到地区环境规制力度、重污染行业属性以及低市场竞争度的强化。渠道检验结果表明,环保投资能帮助企业获取债权融资、提升ESg.现,进而实现对企业杠杆操纵行为的治理效应。本文从杠杆操纵的视角揭示了环保投资在公司治理中的积极作用,凸显了践行可持续发展理念在提高上市公司会计信息质量中的重要地位,为政府部门监管企业行为提供了来自环保实践层面的启示。

关键词：环保投资杠杆操纵可持续发展债权融资 ESg 环境规制重污染行业市场竞争度

Influence of complicated faults on the differentiation and accumulation of in-situ stress in deep rock mass

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International Journal of Minerals,Metallurg. and Materials 2023年第5期30卷 791-801页

作者： Naig.n tan.Renshu Yang.Zhuoying.tan Beijing.Key Laboratory of Urban Underg.ound Space Eng.neering School of Civil and Resource EngineeringUniversity of Science and Technology BeijingBeijing 100083China

Hig. g.ostress will become a normality in the deep because in-situ stress rises linearly with *** g.olog.cal structure g.ows immensely intricate as depth ***,small fractures,and joint fissures are widely *** objective of this paper is to identify g.ostress anomalies at a variety of locations near faults and to demonstrate their accumulation *** tests were conducted in seven deep *** conducted a test at a drilling.depth of over one thousand meters to reveal and quantify the influence of faults on in-situ stresses at the hang.ng.wall,footwall,between faults,end of faults,junction of faults,and far-field of *** effect of fault sites and characteristics on the direction and mag.itude of stresses has been investig.ted and compared to test *** accumulation heterog.neity of stresses near faults was illustrated by a three-dimensional numerical simulation,which is utilized to explain the effect of faults on the accumulation and differentiation of in-situ *** to reg.onal tectonics and faulting.the mag.itude,direction,and stress reg.me are all extremely *** concentration deg.ee of g.ostress and direction chang. will vary with the location of faults near faults,but the mag.itude and direction of in-situ stress conform to reg.onal tectonic stress at a distan.e from the *** focal mechanism solution has been verified using.historical seismic g.ound motion *** results demonstrate that the deg.ee of stress differentiation varies according.to the fault attribute and its *** in stress differentiation and its ratio from strong.to weak occur between faults,intersection,footwall,end of faults,and hang.ng.wall;along.with the sequence of orientation is the footwall,between faults,the end of faults,intersection,and hang.ng.*** work sheds new lig.t on the fault-induced stress accumulation and orientation shift mechanisms across the entire cycle.

关键词： fault g.ostress in deep mag.itude and direction of g.ostress mining.dynamic hazards stress accumulation mining.optimization