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Entropy majorization, thermal adiabatic theorem, and quantum phase transitions

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Frontiers of physics 2012年第2期7卷 244-251页

作者： Shi-jian gu (1) 1. Department of Physics and Institute of Theoretical Physics The Chinese University of Hong Kong Hong Kong China

Let a general quantum many-body system at a low temperature adiabatically cross through the vicinity of the system＇s quantum critical point. We show that the system＇s temperature is signif- icantly suppressed due to both the entropy majorization theorem in quantum information science and the entropy conservation law in reversible adiabatic processes. We take the one-dimensional transverse-field Ising model and the spinless fermion system as concrete examples to show that the inverse temperature might become divergent around the systems＇ critical points. Since the temper- ature is a measurable quantity in experiments, it can be used, via reversible adiabatic processes at low temperatures, to detect quantum phase transitions in the perspectives of quantum information science and quantum statistical mechanics.

关键词： quantum phase transition entropy majorization

A Framework of Convergence Analysis of Mini-batch Stochastic Projected Gradient Methods

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Journal of the Operations Research Society of China 2023年第2期11卷 347-369页

作者： jian gu Xian-Tao Xiao School of Sciences Dalian Ocean UniversityDalian 116023China School of Mathematical Sciences Dalian University of TechnologyDalian 116023China

In this paper,we establish a unified framework to study the almost sure global convergence and the expected convergencerates of a class ofmini-batch stochastic(projected)gradient(SG)methods,including two popular types of SG:stepsize diminished SG and batch size increased *** also show that the standard variance uniformly bounded assumption,which is frequently used in the literature to investigate the convergence of SG,is actually not required when the gradient of the objective function is Lipschitz ***,we show that our framework can also be used for analyzing the convergence of a mini-batch stochastic extragradient method for stochastic variational inequality.

关键词： Stochastic projected gradient method Variance uniformly bounded Convergence analysis

Fidelity spectrum:A tool to probe the property of a quantum phase

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Chinese Physics B 2016年第3期25卷 84-90页

作者： Wing Chi Yu Shi-jian gu Department of Physics and ITR The Chinese University of Hong KongHong KongChina

Fidelity measures the similarity between two states and is widely adapted by the condensed matter community as a probe of quantum phase transitions in many-body systems. Despite its success in witnessing quantum critical points, information about the fine structure of a quantum phase one can get from this approach is still limited. Here, we proposed a scheme called fidelity spectrum, By studying the fidelity spectrum, one can obtain information about the characteristics of a phase. In particular, we investigated the spectra in the one-dimensional transverse-field Ising model and the two- dimensional Kitaev model on a honeycomb lattice. It was found that the sPectra have qualitative differences in the critical and non-critical regions of the two models. From the distributions of them, the dominating k modes in a particular phase could also be captured.

关键词： quantum phase.transitions quantum information quanfized spin models

Optimal placement of piezoelectric active bars in vibration control by topological optimization

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Acta Mechanica Sinica 2008年第6期24卷 699-708页

作者： guozhong Zhao jian Wang Yuanxian gu State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering Mechanics Dalian University of Technology Dalian 116024 China

A continuous variable optimization method and a topological optimization method are proposed for the vibration control of piezoelectric truss structures by means of the optimal placements of active bars. In this optimization model, a zero-one discrete variable is defined in order to solve the optimal placement of piezoelectric active bars. At the same time, the feedback gains are also optimized as continuous design variables. A two-phase procedure is proposed to solve the optimization problem. The sequential linear programming algorithm is used to solve optimization problem and the sensitivity analysis is carried out for objective and constraint functions to make linear approximations. On the basis of the Newmark time integration of structural transient dynamic responses, a new sensitivity analysis method is developed in this paper for the vibration control problem of piezoelectric truss structures with respect to various kinds of design variables. Numerical examples are given in the paper to demonstrate the effectiveness of the methods.

关键词： Piezoelectric intelligent truss Vibrationcontrol Design optimization Sensitivity analysis

Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear Science and Techniques 2024年第3期35卷 208-215页

作者： zhi-Lin Shen jian-Jun He Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational *** this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)He,d(d,p)t,d(p,γ)^(3)He,and p(n,γ)d had the largest influence on the calculated D/H ***,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) He *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method

创新意识和创新能力培养中高校考试改革的探索

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山西医科大学学报（基础医学教育版） 2011年第4期13卷 397-400页

作者：李红枝毛建文古宏标黄榕波邢德刚广东药学院基础学院广州510006

当前高校现有考试制度与考试方式严重制约了学生创新意识和创新能力培养和发展,较难为新时期创新型社会的发展输送适应性人才,改革高校考试方式与考试制度势在必行。根据创新意识和创新能力培养的要求,就基础医学学科课程中实施的考核... 详细信息

当前高校现有考试制度与考试方式严重制约了学生创新意识和创新能力培养和发展,较难为新时期创新型社会的发展输送适应性人才,改革高校考试方式与考试制度势在必行。根据创新意识和创新能力培养的要求,就基础医学学科课程中实施的考核目的、考试内容、考试形式以及激励教师从事考试改革等方面进行了总结,探索出一套有利于创新人才培养的考核制度,有效提高了教育教学质量,较好地为经济社会发展提供具有创新能力的人才。

关键词：考试改革创新能力人才培养

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喉显微外科技术的临床应用及疗效评价

现代医学 2004年第4期32卷 214-216页

作者：冯旭张凤兵黄志纯顾建兴赵静东南大学附属中大医院耳鼻咽喉科江苏南京210009

目的　探讨不同的手术方法对喉部良性病变术后发声功能及嗓音质量的疗效。方法　 1997～ 2 0 0 2年东南大学附属中大医院耳鼻咽喉科应用喉显微外科技术治疗喉部各种良性病变 (声带小结、声带息肉、声带囊肿、Reinke水肿等 ) ,分别采用... 详细信息

目的　探讨不同的手术方法对喉部良性病变术后发声功能及嗓音质量的疗效。方法　 1997～ 2 0 0 2年东南大学附属中大医院耳鼻咽喉科应用喉显微外科技术治疗喉部各种良性病变 (声带小结、声带息肉、声带囊肿、Reinke水肿等 ) ,分别采用咬除、切除、显微黏膜瓣法切除病变 ;对其中的 60例声带息肉患者行前瞻性研究 ,将其随机分为 3组 ,分别采取 3种不同术式 ,于术前、术后 1周、术后 1个月进行喉镜检查及嗓音声学参数检测频率微扰 (jitter ,正常 <0 .5 % )、振幅微扰 (shimmer ,正常 <3 % )和标准化噪声能量 (normalizednoiseenergy ,NNE ,正常 <-10dB) 3种声学参数分析。结果　术后 1个月纤维喉镜检查及频率微扰、振幅微扰和NNE 3种声学参数检测分析显示 ,显微黏膜瓣法组嗓音恢复优于咬除法组和切除法组。结论　喉显微外科技术是治疗喉部良性病变并且能最大限度保留声带发声功能的重要手术方法。

关键词：喉显微外科技术喉疾病声带嗓音分析

Repeater-Assisted Zeno Effect in Classical Stochastic Processes

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Chinese Physics Letters 2012年第1期29卷 17-19页

作者： gu Shi-jian WANG Li-Gang WANG zhi-guo LIN Hai-Qing Department of Physics and ITP The Chinese University of Hong KongHong Kong Department of Physics Zhejiang UniversityHangzhou 310027 Department of Physics Tongji UniversityShanghai 200092

We address the possibility of the classical Zeno effect in classical stochastic processes as sampled by transferring a digitized image through a classical channel with surrounding *** is shown that the the classical state of the image decays inevitably with the distance of the channel due to the interference of the ***,if there are enough repeaters,which can both check and recover the state’s information,the classical state’s decay rate will be significantly suppressed,then a classical Zeno effect might occur.

关键词： decay stochastic digit

Zwitterionic betaines over HEPES as the new generation biocompatible pH buffers for cell culture

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Bioactive Materials 2023年第6期24卷 376-386页

作者： Peiming Liu Jin Sun Wan Peng Yahui gu Xiaoxue Ji zhi Su Pingsheng Liu jian Shen jiangsu Collaborative Innovation Center of Biomedical Functional Materials Jiangsu Key Laboratory of Bio-functional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityJiangsu210023China jiangsu Engineering Research Center of Interfacial Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityJiangsu210093China

Good’s buffers have been widely applied in cell/organ culture over the past half a century as biocompatible pH ***,the emergence of severe adverse effects,such as cellular uptake,lysosomal autophagic activation,and visible light-induced cytotoxicity,raises serious questions over its biocompatibility while underlying mechanism was *** we report that riboflavin(RF,component of cell culture medium)generates ^(1)O_(2),⋅OH,and O_(2)^(·-)under visible light exposure during regular cell *** short half-life reactive oxygen species(ROS)react with tertiary amine groups of HEPES,producing 106.6μM of H_(2)O_(2).Orders of magnitude elevated half-life of ROS in the medium caused severe cytotoxicity and systematic disorder of normal cell *** have further designed and validated zwitterionic betaines as the new generation biocompatible organic pH buffers,which is able to completely avoid the adverse effects that found on HEPES and derivate Good’s *** findings may also open a new avenue for zwitterionic betaine based materials for biomedical applications.

关键词： Good’s buffers Zwitterionic betaines ROS conversion Cellular functions Biocompatibility