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quantum corrections to the entropy in a driven quantum Brownian motion model

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Communications in Theoretical Physics 2021年第9期73卷 136-144页

作者： Tian Qiu hai-tao quan School of Physics Peking UniversityBeijing 100871China Collaborative Innovation Center of quantum Matter Beijing 100871China Frontiers Science Center for Nano-optoelectronics Peking UniversityBeijing100871China

The quantum Brownian motion model is a typical model in the study of nonequilibrium quantum *** is one of the most fundamental physical concepts in *** this work,by solving the quantum Langevin equation,we study the von Neumann entropy of a particle undergoing quantum Brownian *** obtain the analytical expression of the time evolution of the Wigner function in terms of the initial Wigner *** result is applied to the thermodynamic equilibrium initial state,which reproduces its classical counterpart in the high temperature *** on these results,for those initial states having well-defined classical counterparts,we obtain the explicit expression of the quantum corrections to the entropy in the weak coupling ***,we find that for the thermodynamic equilibrium initial state,all terms odd inÿ are exactly *** results bring important insights to the understanding of entropy in open quantum systems.

关键词： quantum Brownian motion time-dependent evolution quantum entropy

quantum Heat Engine and Negative Boltzmann Temperature

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Communications in Theoretical Physics 2017年第9期67卷 347-356页

作者： Jing-Yi Xi hai-tao quan Academy for Advanced Interdisciplinary Studies Peking University Beijing 100871 China School of Physics Peking University Beijing 100871 China Collaborative Innovation Center of quantum Matter Beijing 100871 China

To clarify the ambiguity on negative Boltzmann temperature in literature, we study the Carnot and the Otto cycle with one of the heat reservoirs at the negative Boltzmann temperature based on a canonical ensemble description. The work extraction, entropy production and the efficiency of these cycles are explored. Conditions for constructing and properties of these thermodynamic cycles are elucidated. We find that the apparent "violation" of the second law of thermodynamics in these cycles are due to the fact that the traditional definition of thermodynamic efficiency is inappropriate in this situation. When properly understanding the efficiency and the adiabatic processes, in which the system crosses over "absolute ZERO" in a limit sense, the Carnot cycle with one of the heat reservoirs at a negative Boltzmann temperature can be understood straightforwardly, and it contradicts neither the second nor the third law of thermodynamics. Hence, negative Boltzmann temperature is a consistent concept in thermodynamics. We use a two-level system and an Ising spin system to illustrate our central results.

关键词： quantum heat engines negative Boltzman temperature thermodynamics laws

Effect of roller shapes on strip buckling in a continuous annealing furnace

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International Journal of Minerals,Metallurgy and Materials 2011年第3期18卷 297-302页

作者： Jing Yang Di Tang Lan Su hai-tao Jiang quan Yang National Engineering Research Center of Advanced Rolling University of Science and Technology Beijing Beijing 100083 China

The effect of roller shapes on strip buckling in a continuous annealing furnace was focused on. The tensile stress distribution, the transverse compressive stress, and the critical buckling stress of the strip were studied by the finite element method （FEM） when the flat roller, crown roller, single taper roller, and double taper roller were used, respectively. Simulation results show that strip buckling is most likely to occur with the crown roller, then the double taper roller, and finally the single taper roller. Also, strip buckling can not occur when the flat roller is used. Considering strip snaking, the single taper roller and double taper roller are suggested in the continuous annealing fur-nace. The double taper roller with a better strip snaking-prevention ability should be applied in the sections with high strip temperature, and the single taper roller with a better buckling-prevention ability should be used in the sections with low strip temperature.

关键词： steel strips buckling heat treating furnaces annealing rollers finite element method

The uniqueness of the integration factor associated with the exchanged heat in thermodynamics

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Fundamental Research 2021年第1期1卷 6-9页

作者： Yu-Han Ma Hui Dong hai-tao quan Chang-Pu Sun Beijing Computational Science Research Center Beijing 100193China Graduate School of China Academy of Engineering Physics No.10 Xibeiwang East RoadHaidian DistrictBeijing 100193China School of Physics Peking UniversityBeijing 100871China

State functions play important roles in *** from the process function,such as the exchanged heatδQ and the applied workδW,the change of the state function can be expressed as an exact *** prove here that,for a generic thermodynamic system,only the inverse of the temperature,namely 1/T,can serve as the integration factor for the exchanged heatδ*** uniqueness of the integration factor invalidates any attempt to define other state functions associated with the exchanged heat,and in turn,reveals the incorrectness of defining the entransy E_(vh)=CVT^(2)/2 as a state function by treating T as an integration *** further show the errors in the derivation of entransy by treating the heat capacity C_(V)as a temperature-independent constant.

关键词： Integration factor Process function Exchanged heat Thermodynamic entropy Uniqueness theorem

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百万千瓦核级发电机局部放电试验研究

核动力工程 2011年第S2期32卷 58-62页

作者：周利李刚陶海泉曹邦伟潘凯中广核工程有限公司广东深圳518057

发电机局部放电试验是监测和预防定子绕组绝缘缺陷的有效手段。通过对岭澳核电站3、4号发电机及红沿河核电厂1号发电机的局部放电试验,研究了首批国产级百万千瓦核级大型水内冷发电机局部放电量超出国家标准范围的问题,找到了此类型发... 详细信息

发电机局部放电试验是监测和预防定子绕组绝缘缺陷的有效手段。通过对岭澳核电站3、4号发电机及红沿河核电厂1号发电机的局部放电试验,研究了首批国产级百万千瓦核级大型水内冷发电机局部放电量超出国家标准范围的问题,找到了此类型发电机局部放电异常的原因,得出了局部放电量偏大是其固有特性的结论,为同型机组的安全投运及局部放电试验评价提供了理论依据。

关键词：核级发电机局部放电试验标准

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浙江省血吸虫病防治历程和展望

国际流行病学传染病学杂志 2008年第6期35卷 361-364页

作者：闻礼永陶海全浙江省医学科学院寄生虫病研究所杭州 310013

浙江省曾是全国血吸虫病重度流行省份之一，经过50多年的积极防治，全省于1987年达到血吸虫病传播控制标准，1995年达到血吸虫病传播阻断标准，1996年转入监测巩固阶段，血防工作取得举世瞩目的成就。今年，我们纪念毛泽东同志《送瘟神... 详细信息

浙江省曾是全国血吸虫病重度流行省份之一，经过50多年的积极防治，全省于1987年达到血吸虫病传播控制标准，1995年达到血吸虫病传播阻断标准，1996年转入监测巩固阶段，血防工作取得举世瞩目的成就。今年，我们纪念毛泽东同志《送瘟神二首》发表50周年暨血吸虫病在浙江发现100周年，回顾浙江省血吸虫病防治历程和成就，总结经验和教训，进一步巩固全省血防成果。

关键词：血吸虫病控制钉螺

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发电机转子注入式保护方案研究

企业科技与发展 2008年第20期 111-112+115页

作者：李磊陶海泉广西电力工业勘察设计研究院深圳南瑞科技有限公司

文章介绍了一种不依赖自身电量的注入式转子接地保护的新方案,分析表明该方案有较好的故障反映能力。其特点是,在机组停机情况下能够检测出转子接地情况,克服了常规乒乓式原理在机组停机情况下无法运作的缺点。在实验室中的试验结果表... 详细信息

文章介绍了一种不依赖自身电量的注入式转子接地保护的新方案,分析表明该方案有较好的故障反映能力。其特点是,在机组停机情况下能够检测出转子接地情况,克服了常规乒乓式原理在机组停机情况下无法运作的缺点。在实验室中的试验结果表明理论与实验相符。

关键词：转子保护注入式

基于分段完成低压母线故障的有选择性快速保护

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继电器 2007年第21期35卷 7-9页

作者：曾院辉刘丁陶海泉李磊深圳南瑞科技有限公司广东深圳518040

变电站内低压母线设置快速保护具有非常重要的意义,实现快速保护主要问题是区分母线故障和线路近区故障,对于并列运行的低压母线还需区分故障母线和非故障母线。提出了一种新的在并列运行下区分故障母线和非故障母线的方法。通过现场总... 详细信息

变电站内低压母线设置快速保护具有非常重要的意义,实现快速保护主要问题是区分母线故障和线路近区故障,对于并列运行的低压母线还需区分故障母线和非故障母线。提出了一种新的在并列运行下区分故障母线和非故障母线的方法。通过现场总线传送线路动作闭锁信息、分段的功率方向或电流矢量到变压器后备保护。后备保护通过线路动作闭锁信息区分母线故障和线路故障,通过分段的功率方向或电流矢量区分故障母线和非故障母线,实现低压母线保护的快速性和选择性。经过工程测试,通过该方法实现的低压母线保护动作快速、准确,具有工程应用价值。

关键词：微机保护低压母线现场总线

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重型破裂脑动脉瘤的手术治疗

中华神经外科杂志 2008年第11期24卷 848-850页

作者：杨立庄杨海城马东营陶海泉于文元哈尔滨医科大学附属第二医院神经外科 150086

目的探讨重型破裂脑动脉瘤的急性期手术疗效。方法在急性期首先通过去骨瓣减压、血肿清除、脑室外引流等手术减轻病情后，进一步对动脉瘤进行手术。结果Hunt—Hess分级Ⅳ级50例，26例优，13例良，8例差，3例死亡。Ⅴ级者8例，2例优，1... 详细信息

目的探讨重型破裂脑动脉瘤的急性期手术疗效。方法在急性期首先通过去骨瓣减压、血肿清除、脑室外引流等手术减轻病情后，进一步对动脉瘤进行手术。结果Hunt—Hess分级Ⅳ级50例，26例优，13例良，8例差，3例死亡。Ⅴ级者8例，2例优，1例良，2例差，3例死亡。结论重型破裂脑动脉瘤急性期应首选手术治疗，可取得满意的疗效。

关键词：颅内动脉瘤显微外科手术临床分析治疗方法