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随机无序对一维Kitaev模型拓扑和局域化特性的影响

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山西大学学报(自然科学版) 2024年第4期47卷 792-803页

作者：刘晓阳武晔虹陆展鹏徐志浩山西大学理论物理研究所山西大学量子光学与光量子器件国家重点实验室山西医科大学基础医学院山西大学极端光学协同创新中心

本文研究了在位无序、跃迁无序、超导配对无序和这三种无序都有的完全无序对Kitaev模型拓扑特性、态密度（DOS）和局域化性质的影响。这种影响可能会诱发新的拓扑相，也可能使已有的拓扑特性消失。通过对比DOS和拓扑相图的结果，发现DO... 详细信息

本文研究了在位无序、跃迁无序、超导配对无序和这三种无序都有的完全无序对Kitaev模型拓扑特性、态密度（DOS）和局域化性质的影响。这种影响可能会诱发新的拓扑相，也可能使已有的拓扑特性消失。通过对比DOS和拓扑相图的结果，发现DOS中存在零模峰并不能作为探测拓扑相变的证据。最后以在位无序效应为例，分析了有限尺寸情况下的Kitaev模型的局域化性质。

关键词： Majorana费米子 Z2拓扑不变量 Lyapunov指数态密度

来源：博看期刊

Stress Corrosion Cracking of Nitrogen-containing Stainless Steel 316LN in High Temperature Water Environments

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Chinese Journal of Mechanical Engineering 2010年第6期23卷 677-683页

作者： YANG Wu LI Guangfu HUANG Chunbo ZHOU Jianjiang lu zhanpeng Shanghai Research Institute of Materials Shanghai 200437 China Shanghai Key Laboratory for Engineering Materials Evaluation Shanghai 20043 7 China

Stress corrosion cracking （SCC） of stainless steels and Ni-based alloys in high temperature water coolant is one of the key problems affecting the safe operation of nuclear power plants （NPPs）. The nitrogen-added stainless steel is a kind of possible candidate materials for mitigating SCC since reducing the carbon content and adding nitrogen to offset the loss in strength caused by the decrease in carbon content can mitigate the problem of sensitization. However, the reports of SCC of nitrogen-added stainless steels in high temperature water are few available. The effects of applied potential and sensitization treatment on the SCC of a newly developed nitrogen-containing stainless steel （SS） 316LN in high temperature water doped with chloride at 250 ℃ were studied by using slow strain rate tests （SSRTs）. The SSRT results are compared with our data previously published for 316 SS without nitrogen and 304NG SS with nitrogen, and the possible mechanism affecting the SCC behaviors of the studied steels is also discussed based on SSRT and microstucture analysis results. The susceptibility to cracking of 316LN SS normally increases with increasing potential. The susceptibility to SCC of 316LN SS was less than that of 316 SS and 304NG SS. Sensitization treatment at 700℃ for 30 h showed little effect on the S CC of 316LN S S and significant effect on the S CC of 316 S S. The predominant cracking mode for the 316LN S S in both annealed state and the state after the sensitization treatment was transgranular. The presented conditions of mitigating stress corrosion cracking are some useful information for the safe use of 316LN SS in NPPs.

关键词： nitrogen-containing stainless steel stress corrosion cracking (SCC) potential sensitization slow strain rate test (SSRT)

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二氧化碳腐蚀机理及影响因素

石油学报 1995年第3期16卷 134-139页

作者：郑家吕战鹏华中理工大学

利用自制高温、高压腐蚀试验及电化学测试试验装置，用失重法、电化学极化曲线、扫描电镜及Ｘ射线衍射分析，研究了碳钢在ＣＯ＿２饱和的３％ＮａＣｌ溶液中ＣＯ＿２分压、温度对碳钢腐蚀的影响，结果表明，在较低温度（７０℃）时，碳... 详细信息

利用自制高温、高压腐蚀试验及电化学测试试验装置，用失重法、电化学极化曲线、扫描电镜及Ｘ射线衍射分析，研究了碳钢在ＣＯ＿２饱和的３％ＮａＣｌ溶液中ＣＯ＿２分压、温度对碳钢腐蚀的影响，结果表明，在较低温度（７０℃）时，碳钢腐蚀速率对数与ＣＯ＿２分压对数成线性关系，与ＤｅＷａａｒｄ等人的研究结果相符；７０℃时，腐蚀产物的附着力及耐蚀性很差，此时增大ＣＯ＿２分压加速腐蚀反应的阴极过程；１１０℃时碳钢腐蚀产物为致密的碳酸亚铁膜，此膜对金属基体的附着力较强、保护性好，温度对ＣＯ＿２腐蚀产物有明显的影响。文中还探讨了缓蚀剂抑制ＣＯ＿２腐蚀。

关键词：二氧化碳腐蚀石油机械设备

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高温水中应力腐蚀开裂机理及扩展模型

中国材料进展 2019年第7期38卷 651-662,650页

作者：吕战鹏上海大学材料科学与工程学院上海大学省部共建高品质特殊钢冶金与制备国家重点实验室

核电站结构材料在高温水中应力腐蚀开裂是影响安全运行的重要因素。总结了合金成分、载荷和环境介质等多种因素对奥氏体合金在高温水中应力腐蚀开裂扩展过程的影响规律,简要介绍了几种应力腐蚀开裂机理模型。分析了高温水中的应力腐蚀... 详细信息

核电站结构材料在高温水中应力腐蚀开裂是影响安全运行的重要因素。总结了合金成分、载荷和环境介质等多种因素对奥氏体合金在高温水中应力腐蚀开裂扩展过程的影响规律,简要介绍了几种应力腐蚀开裂机理模型。分析了高温水中的应力腐蚀开裂基元过程,提出了载荷对合金在高温水中界面反应的物理加速作用和物理化学加速作用原理。发展了基于连续介质力学裂纹尖端力学场与氧化动力学相结合的裂纹扩展速率的形变/氧化交互作用理论模型,针对模型中使用的准固态氧化动力学规律以及裂尖渐进场的适用性进行了分析,发现环境温度、材料成分和水化学对氧化动力学的影响与相应条件下奥氏体合金应力腐蚀开裂行为变化特征相对应,裂尖渐进场的适用性也得到了验证。将形变/氧化交互作用模型应用于多种条件下不锈钢和镍基合金在压水堆一回路水中应力腐蚀开裂扩展速率评价,所得模型预测结果与实验室和现场数据结果相一致。

关键词：应力腐蚀开裂核电站,高温水裂纹扩展速率氧化动力学裂尖应变速率

Optical grade (Gd_(0.95-x)lu_(x)Eu_(0.05))_(3)Al_(5)O_(12) ceramics with near-zero optical loss: Effects of lu^(3+) doping on structural feature, microstructure evolution, and far-red luminescence

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Journal of Advanced Ceramics 2024年第1期13卷 113-123页

作者： Zhigang Sun Ji-Guang Li Huiyu Qian Yoshio Sakka Tohru SSuzuki Bin lu School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315211China Research Center for Electronic and Optical Materials National Institute for Materials ScienceIbaraki 305-0044Japan Key Laboratory of Photoelectric Detection Materials and Devices of Zhejiang Province Ningbo 315211China

A chemical co-precipitation strategy was employed to synthesize a series of(Gd_(0.95−x)lu_(x)Eu_(0.05))_(3)Al_(5)O_(12)(x=0.1−0.95)powder phosphors,followed by vacuum sintering to achieve transparent garnet ceramic *** density functional theory indicated lu_(3)Al_(5)O_(12) was formed in priority compared with Gd_(3)Al_(5)O_(12) during solid-phase *** high-temperature sintering,the lu^(3+)substitution for Gd^(3+)suppressed point mass diffusion leading to a smaller grain *** in-line transmittances of bulk specimens with x=0.1,0.3,0.5,0.7,and 0.95 nm were~83.5%,80.1%,68.8%,73.7%,and 82.2%at 710 nm(Eu^(3+)emission center),respectively,among which the sample of x=0.1 exhibited the optical grade with near-zero optical loss in agreement with the defect-free single crystal(~100%of the theoretical transmittance).The resulting particle and ceramic materials both presented characteristic Eu^(3+)emission arising from 5D0→7FJ(J=1−4)transition,where the dominant far-red emission at~710 nm arising from ^(5)D_(0)→^(7)F_(4) transition overlapped with the absorption of phytochrome(PFR).The photoluminescence excitation and photoluminescence intensities of(Gd_(0.95−x)lu_(x)Eu_(0.05))_(3)Al_(5)O_(12) powders and ceramics generally increased at a higher Gd^(3+)/lu^(3+)***^(3+)dopants delayed the fluorescence lifetime while the bulk samples had shorter lifetime compared to the particle *** transparent(Gd_(0.85)lu_(0.1)Eu_(0.05))3Al_(5)O_(12) ceramic phosphor exhibited good thermal stability with a high thermal quenching temperature above 533 *** designed ceramic phosphor-converted light-emitting diode had a saturation injection current of 435 mA and a current-dependent color rendering *** importantly,our report marked the developmental stage of transparent ceramic materials towards zero optical loss.

关键词： transparent ceramics garnet phosphors light-emitting diode(LED) optical properties Gibbs free energy

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英国工党中间道路的回归及其影响

现代国际关系 2024年第8期 61-81,142页

作者：王展鹏陆准北京外国语大学英国研究中心北京外国语大学区域与全球治理高等研究院

2010年以来英国工党经历了从左翼激进政策到务实中间道路的转变:在意识形态上,向市场导向的社会民主主义倾斜,强调实现“国家复兴”;在经济上,以“安全经济学”为基础、以产业政策为抓手统筹增长、产业和社会政策目标;在对外战略上提出... 详细信息

2010年以来英国工党经历了从左翼激进政策到务实中间道路的转变:在意识形态上,向市场导向的社会民主主义倾斜,强调实现“国家复兴”;在经济上,以“安全经济学”为基础、以产业政策为抓手统筹增长、产业和社会政策目标;在对外战略上提出“进步现实主义”的理念,力图实现在西方主导的国际秩序中发挥关键角色和促进国家繁荣目标之间的平衡。英国工党的中间道路回归是大变局下英国政党政治逻辑和诸多内外部危机共同驱动的结果,也面临英国自身现实和全球、地区层面变化的诸多制约。随着工党在2024年大选中获胜,其执政理念与政策实践将对英国未来的政治格局、经济社会发展和国际角色演变产生深刻影响,成为英国能否走出近年来国家治理困境的一个重要节点。

关键词：英国工党中间道路大选意识形态

含重铬酸根硫酸溶液中磁场对铁自腐蚀状态及极化电阻的影响

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中国腐蚀与防护学报 2000年第4期20卷 230-236页

作者：吕战鹏黄德伦杨武赵国珍上海材料研究所上海200437

铁在含有一定浓度重铬酸根的硫酸中，自腐蚀状态下的阴极反应速率受重铬酸根阴极还原电子转移过程与扩散过程共同控制．外加磁场使铁的自腐蚀电位正移，且电位正移幅度随重铬酸根浓度增加而增大．在没有外加磁场时的自腐蚀电位下进行恒... 详细信息

铁在含有一定浓度重铬酸根的硫酸中，自腐蚀状态下的阴极反应速率受重铬酸根阴极还原电子转移过程与扩散过程共同控制．外加磁场使铁的自腐蚀电位正移，且电位正移幅度随重铬酸根浓度增加而增大．在没有外加磁场时的自腐蚀电位下进行恒电位极化时，外加磁场后会出现阴极电流，磁致阴极电流随重铬酸根的浓度增大而显著增大．外加磁场会使含有一定量重铬酸根的硫酸溶液中铁的极化电阻显著下降．通过对磁场作用进行模型化，分析了磁场作用的动力学机理．磁场对阴极扩散过程的加速作用导致了自腐蚀电位正移及磁致阴极电流，而磁场引起自腐蚀电位的正移是引起极化电阻减小的主要原因．

关键词：磁场自腐蚀电位极化电阻重铬酸根硫酸

Collective Molecular Machines: Multidimensionality and Reconfigurability

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Nano-Micro Letters 2024年第8期16卷 309-340页

作者： Bin Wang Yuan lu Department of Chemical Engineering Tsinghua UniversityBeijing 100084People’s Republic of China Key Laboratory of Industrial Biocatalysis Ministry of EducationTsinghua UniversityBeijing 100084People’s Republic of China

Molecular machines are key to cellular activity where they are involved in converting chemical and light energy into efficient mechanical *** the last 60 years,designing molecular structures capable of generating unidirectional mechanical motion at the nanoscale has been the topic of intense *** progress has been made,attributed to advances in various fields such as supramolecular chemistry,biology and nanotechnology,and ***,individual molecular machines are only capable of producing nanometer work and generally have only a single *** order to address these problems,collective behaviors realized by integrating several or more of these individual mechanical units in space and time have become a new *** this review,we comprehensively discuss recent developments in the collective behaviors of molecular *** particular,collective behavior is divided into two *** is the appropriate integration of molecular machines to efficiently amplify molecular motions and deformations to construct novel functional *** other is the construction of swarming modes at the supramolecular level to perform nanoscale or microscale *** discuss design strategies for both modes and focus on the modulation of features and ***,in order to address existing challenges,the idea of transferring experience gained in the field of micro/nano robotics is presented,offering prospects for future developments in the collective behavior of molecular machines.

关键词： Molecular machines Collective control Collective behaviors DNA Biomolecular motors

Soil inorganic amendments produce safe rice by reducing the transfer of Cd and increasing key amino acids in brown rice

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Journal of Environmental Sciences 2024年第2期136卷 121-132页

作者： Fanyi Kong Shenggao lu Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment Key Laboratory of Environmental Remediation and Ecosystem HealthMinistry of EducationCollege of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China

The digestibility of cadmium(Cd)in brown rice is directly related to amino acid metabolism in rice and human *** our field study,three kinds of alkaline calcium-rich soil inorganic amendments(SIAs)at three dosages were applied to produce safe rice and improve the quality of rice in Cd-contaminated *** the increased application of SIA,Cd content in iron plaque on rice root significantly increased,the transfer of Cd from rice root to grain significantly decreased,and then Cd content in brown rice decreased *** vitro digestibility of Cd in brown rice was estimated by a physiologically based extraction *** showed that more than 70%of Cd in brown rice could be digested by simulated gastrointestinal *** on the total and digestible Cd contents in brown rice to evaluate the health risk,the application of 2.25 ton SIA/ha could produce safe rice in acidic slightly Cd-contaminated paddy *** amino acids(AAs)in brown rice were determined by high-performance liquid *** contents of 5 key AAs(KAAs)that actively respond to environmental changes increased significantly with the increased application of *** structural equation model indicated that KAAs could be affected by the Cd translocation capacity from rice root to grain,and consequently altered the ratio of indigestible Cd in brown *** formation of indigestible KAAs-Cd complexes by combining KAAs(phenylalanine,leucine,histidine,glutamine,and asparagine)with Cd in brown rice could be considered a potential mechanism for reducing the digestibility of Cd.

关键词： Cadmium digestibility Soil inorganic amendments Safe rice Amino acid Priming effect Health risk