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材料科学与工程（中英文A版） 2024年第1期14卷 26-33页

作者： Mogahabo Tebogo Morukuladi N.l.lethole M.C.Masedi N.N.Ngoepe P.E.Ngoepe Materials Modelling Centre University of LimpopoPrivate Bag x1106Sovenga 0727South Africa Department of Physics University of Fort HareAlice 5700South Africa

The universal cluster expansion technique was used in this study to determine the binary phase diagrams for the transition metal carbonate precursors MCO3(M:Mn,Ni,Co).The use of mixed cathode materials in lithium-ion batteries such as NMC(Ni,Mn and Co)formulations,is a strategic approach to optimize performance,enhance safety and address cost and environmental considerations in the rapidly evolving field of energy *** study focuses on the cost issue related to lithium ion batteries by investigating the manganese rich NMC since manganese is more abundant and *** doped MnCO3 with nickel and doped MnCO3 with cobalt then ran cluster expansion cal.ulations to generate binary *** binary phase diagrams generated indicated that doping MnCO3 with nickel favours the Mn-rich side,while doping MnCO3 with cobalt favours 50%Mn-rich and 50%*** further extracted the most stable structures from both binary diagrams and determined their electronic,mechanical and vibrational stabilities using DFT(density functional theory)cal.ulations within the lDA(local gradient approximation)with Hubbard parameter(u).The electronic properties revealed that both materials are semiconductors due to their narrow energy band gap obtained while the mechanical properties showed that structures are mechanically stable since their necessary conditions for trigonal and triclinic systems were satisfied.

关键词： Binary phase diagrams mechanical properties electronic conductivity phonon dispersion curves.

Focal distance tabu search

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Science China(Information Sciences) 2021年第5期64卷 5-16页

作者： Fred GlOVER Zhipeng lü Meta-Analytics Inc. School of Computer Science and Technology Huazhong University of Science and Technology

Focal distance tabu search modifies a standard tabu search algorithm for binary optimization by augmenting a periodic diversification step that drives the search away from a current best(or elite) solution until the objective function deteriorates beyond a specified threshold or until attaining a lower bound on the distance from the originating solution. The new augmented algorithm combines the threshold and lower bound approaches by introducing an initial focal distance for the lower bound which is updated when the diversification step is completed. However, rather than terminating the diversification step at the customary completion point, focal distance tabu search(TS) retains the focal distance bound through additional search phases designed to improve the objective function, drawing on a strategy proposed with strategic *** algorithm realizes this strategy by partitioning the variables into two sets which are managed together with an abbreviated tabu search process. An advanced version of the approach drives the search away from a collection of solutions rather than a single originating solution, introducing the concept of a signature solution to guide the search. The method can be employed to augment a variety of other metaheuristic algorithms such as those using threshold procedures, late acceptance hill climbing, iterated local search, breakout local search, GRASP, and path relinking.

关键词： tabu search diversification strategic oscillation adaptive partitioning metaheuristics

双镜联合治疗胆囊结石合并肝外胆管结石患者的疗效及安全性分析

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中国现代药物应用 2024年第10期18卷 36-40页

作者：宋金珂田盛霞胡家艳李卿明贵州中医药大学第一附属医院肝胆外科 550001 通用医疗三○○医院肿瘤科 550006

目的对胆囊结石合并肝外胆管结石患者采用双镜联合(腹腔镜联合十二指肠镜)治疗的临床效果和安全性进行分析。方法选择103例胆囊结石合并肝外胆管结石患者,根据手术方案不同分为观察组(61例,行双镜联合下胆囊切除术)和对照组(42例,实施... 详细信息

目的对胆囊结石合并肝外胆管结石患者采用双镜联合(腹腔镜联合十二指肠镜)治疗的临床效果和安全性进行分析。方法选择103例胆囊结石合并肝外胆管结石患者,根据手术方案不同分为观察组(61例,行双镜联合下胆囊切除术)和对照组(42例,实施传统开腹手术)。比较两组围术期指标[手术时间、住院时间、出血量、术后视觉模拟评分法(VAS)评分、结石清除率]、血清应激指标[肿瘤坏死因子-α(TNF-α)、白细胞介素-6(Il-6)、C反应蛋白(CRP)、皮质醇(Cor)]、肝功能指标[谷丙转氨酶(AlT)、谷草转氨酶(AST)、γ-谷氨酰转移酶(GGT)]、并发症发生率。结果两组结石清除率均为100.0%,比较无明显差异(P>0.05)。观察组的手术时间(96.3±7.5)min和住院时间(7.5±2.1)d短于对照组的(119.2±10.2)min、(9.4±1.2)d,出血量(25.8±5.4)ml少于对照组的(46.3±6.9)ml,术后VAS评分(2.9±0.8)分低于对照组的(3.4±0.7)分(Pl-6、CRP、Cor水平比较无明显差异(P>0.05);术后7 d,两组血清中TNF-α、Il-6、CRP、Cor水平均明显高于术前,但观察组明显低于对照组(PlT、AST、GGT比较,无明显差异(P>0.05)。术后7 d,观察组的AlT(43.9±4.3)u/l、AST(40.4±4.1)u/l、GGT(154.2±12.9)u/l均低于对照组的(56.9±6.4)、(49.2±5.1)、(193.3±26.5)u/l(P<0.05)。观察组并发症发生率为4.92%,低于对照组的21.43%,差异有统计学意义(P<0.05)。结论胆囊结石合并肝外胆管结石患者治疗中采用双镜联合下胆囊切除术治疗,能够改善围术期各项指标,并使得术后应激反应得到减轻,促进患者的术后恢复,并发症风险也大大降低,因此该方案值得在临床上推广。

关键词：腹腔镜十二指肠镜胆囊切除术胆囊结石肝外胆管结石安全性疗效

Tempo-spatial distribution of ulva ***-propagules in the Yellow Sea during and after green tide in 2019

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Journal of Oceanology and limnology 2022年第6期40卷 2462-2472页

作者： Jin ZHAO Fanzhou KONG Qianchun l.u Fengjie lI Xiu WEI tian YAN Peng JIANG CAS and Shandong Province Key laboratory of Experimental Marine Biology Center for Ocean Mega-ScienceInstitute of OceanologyChinese Academy of SciencesQingdao 266071China laboratory for Marine Biology and Biotechnology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China CAS Key laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China laboratory of Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China university of Chinese Academy of Sciences Beijing 100049China College of life Science Qingdao UniversityQingdao 266071China

large-scale green tides occur frequently in summer in the Yellow Sea in recent ***,providing“seeds”for the seaweeds,play an important role in the formation of green *** studied the distribution pattern and genetic composition of the ulva micro-propagules in the Yellow Sea during and after the green tide in *** April,a great amount of ulva micro-propagules was detected in the Subei Shoal,with the average density of 908 inds./l,being similar to that of previous *** was found out at a low percentage(4%),and 25%of them were positive when tested by the specific marker for the floating *** percentage of *** was obviously lower than that in the same season from 2009 to ***,the quantity of *** micro-propagules sharply *** variation in composition of the micro-propagules in Subei radial sand ridges was revealed in the background of the alternation of macroalgal tides in the Yellow Sea in the latest *** the green tide in June and July,ulva micro-propagules were detected from some nearshore sites where the floating seaweeds distributed,and *** was the dominate *** September,when the green tide ended,no ulva micro-propagule was detected from the open sea area of the Yellow *** is indicated that the green algae micro-propagules were unlikely to exist in the open water of the Yellow Sea for a long time according to the large-scale *** mechanism of preserving micro-propagules in Subei radial sand ridges,and the destination of *** micro-propagules in the open sea area of the Yellow Sea after green tide deserves further study.

关键词： green tide ulva prolifera micro-propagule Yellow Sea

Time Dependant Weld Shape in Ar-O_2 Shielded Stationary GTA Welding

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Journal of Materials Science & Technology 2007年第5期23卷 650-654页

作者： Shanping l.u Dianzhong lI Hidetoshi Fujii Kiyoshi Nogi Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 Chian Joining and Welding Research Institute Osaka University Osaka567-0047 Japan

The stationary gas tungsten arc welding （GTA） is carried out on SuS304 stainless steel.under Ar-0.1%O2 and Ar-0.3%O2 mixed shielding to observe the evolution of the molten pool and investigate the role of Marangoni convection on the weld shape. After welding, the oxygen content in the weld metal was measured by using an oxygen/nitrogen analyzer. Small addition of oxygen to the argon based shielding gas can effectively adjust the weld pool oxygen content. Oxygen plays an important role as an surface active element in determining the pattern of Marangoni convection in the stainless steel weld pool. When the weld metal oxygen content is over the critical value, 0.01 wt pct, corresponding to the Ar-0.3%O2 mixed shielding gas, the Marangoni convection changes from outward to inward direction and the weld shape dramatically changes from wide shallow shape to narrow deep shape.

关键词： Marangoni convection Oxygen Weld shape

基于界面追踪-动网格技术模拟凝固收缩下Fe-C合金宏观偏析

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金属学报 2024年第3期60卷 388-404页

作者：董士虎张红伟吕文朋雷洪王强东北大学材料电磁过程研究教育部重点实验室沈阳110819 东北大学冶金学院沈阳110819

Fe-C系合金铸锭因C元素分配系数小、铸锭尺寸较大,易产生C偏析缺陷;同时因合金液-固相密度差异以及铁素体、奥氏体等相密度的差异都易产生并加剧凝固收缩。对凝固收缩的模拟研究表明,气相(渣相)的引入对偏析影响甚微,主要起补充顶端收... 详细信息

Fe-C系合金铸锭因C元素分配系数小、铸锭尺寸较大,易产生C偏析缺陷;同时因合金液-固相密度差异以及铁素体、奥氏体等相密度的差异都易产生并加剧凝固收缩。对凝固收缩的模拟研究表明,气相(渣相)的引入对偏析影响甚微,主要起补充顶端收缩腔的作用,但却导致气-合金界面模拟困难。为了简化模拟的复杂性,本工作基于液-固混相的连续介质模型,将凝固过程中收缩的体积与固相区、糊状区及液相区下降的体积建立关联,从而确定熔体顶端边界;结合动网格技术,开发了一种追踪收缩腔界面的模型,实现了Fe-C合金铸锭凝固收缩和宏观偏析的耦合模拟,预测的收缩腔形状与实验相符。结果表明:Fe-0.3%C合金铸锭凝固过程中,在热-溶质浮升力影响的基础上,考虑凝固收缩后,预测的铸锭顶部正偏析最大值减少了4.78%。铸锭顶端界面的换热,会减轻铸锭顶端正偏析。耦合热-溶质浮升力及凝固收缩影响,顶端与环境换热系数为h=2.0 W/(m^(2)·K)的铸锭上部溶质分布更符合文献实验测量结果。在热-溶质浮升力影响的基础上,考虑凝固收缩增强了糊状区内溶质浮力影响,致使铸锭凝固前沿主流股旋流方向更快反转,熔钢流速超过仅考虑热-溶质浮升力时的流速,从而加快了铸锭凝固速率。本模型预测的铸锭底端负偏析小于文献实验结果,这是由于本模型仅考虑了液-柱状晶混相,进一步的模型中需加入等轴晶粒沉降的影响。

关键词： Fe-C合金凝固收缩宏观偏析界面追踪动网格

广义径向基函数神经网络在热误差建模中的应用

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光学精密工程 2015年第6期23卷 1705-1713页

作者：吕程刘子云刘子建余治民湖南大学汽车车身先进设计制造国家重点实验室湖南长沙410082

针对现有的热误差建模方法建模效率低,模型预测精度不理想等问题,提出了广义径向基函数神经网络(RBF)建模方法并将其应用于数控机床热误差建模中。讨论了采用广义RBF神经网络进行热误差建模的原理及步骤。以数控导轨磨床主轴箱系统为例... 详细信息

针对现有的热误差建模方法建模效率低,模型预测精度不理想等问题,提出了广义径向基函数神经网络(RBF)建模方法并将其应用于数控机床热误差建模中。讨论了采用广义RBF神经网络进行热误差建模的原理及步骤。以数控导轨磨床主轴箱系统为例,布置了12个主轴热误差的关键温度测点,测得了2组独立的主轴箱系统热误差数据。将测得的数据分别用于建立主轴箱系统热误差广义RBF神经网络预报模型和验证模型的准确性。研究结果表明,热误差广义RBF神经网络模型具有预测精度高及泛化能力强的优点;与传统的RBF神经网络建模方法相比,提出的广义RBF神经网络建模方法建模效率更高,模型鲁棒性及预测性能更好,是一种可以用于数控机床热误差实时补偿的有效建模方法。

关键词：广义径向基函数神经网络热误差建模聚类算法泛化能力鲁棒性数控导轨磨床

THE RIGHT TO EMPlOYMENT SECuRITY IN CHINESE lABOR lAW： lATEST DEVElOPMENTS IN lIGHT OF INTERNATIONAl lAW

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Frontiers of law in China-Selected Publications from Chinese universities 2015年第1期10卷 136-160页

作者： l.u Haina School of law Renmin University of China Beijing 100872 China

Employment security is very often examined from a labor law rather than a human rights perspective. This article looks at the employment security in Chinese labor law from a human rights perspective. The right to employment security includes both negative and positive aspects： a negative right to protection against unfair dismissal, including dismissal for cause and economic redundancy, and a positive right to employment stability. Comparing Chinese labor law with international standards, this article focuses on analyzing important changes in the legislative developments in China in the past years, such as severance pay, labor contract with indefinite duration, and labor dispatching. This article also points out the main deficiencies, such as dismissal on the ground of criminal liabilities, weakness of trade unions and law enforcement, and no exemption of small employers. The article concludes with observing a tendency of Chinese law getting closer to international standards and pointing out the approach China should follow： to enhance employability through vocational training and providing better social security when strengthening the legislative protection of employment security.

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新疆阿尔泰将军山天河石花岗岩的岩石成因及其对铷成矿的制约

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岩石学报 2024年第3期40卷 907-926页

作者：佘贵民刘堃周晋捷吕正航张辉中国科学院地球化学研究所地球内部物质高温高压实验室贵阳550081 中国科学院大学地球与行星科学学院北京100049

新疆阿尔泰盛产稀有金属伟晶岩,但缺乏数量上相当的高分异花岗岩。将军山天河石花岗岩是阿尔泰目前发现的唯一富Rb花岗岩,但其岩石成因、Rb的赋存状态及其与周边伟晶岩的关系尚不清楚,从而制约了对Rb富集机理和成矿潜力的认识。据此,本... 详细信息

新疆阿尔泰盛产稀有金属伟晶岩,但缺乏数量上相当的高分异花岗岩。将军山天河石花岗岩是阿尔泰目前发现的唯一富Rb花岗岩,但其岩石成因、Rb的赋存状态及其与周边伟晶岩的关系尚不清楚,从而制约了对Rb富集机理和成矿潜力的认识。据此,本文对将军山天河石花岗岩和伟晶岩开展了全岩组成、年代学、同位素和矿物学研究。结果显示,阿尔泰将军山天河石花岗岩为高分异的A型花岗岩,独居石u-Pb年龄为276.9±2.7Ma,表明形成于早二叠世。独居石Nd同位素组成(ε_(Nd)(t)为+4.15~+6.05,二阶段模式年龄t DM2为548~708Ma)显示亏损的源区特征,表明源自新生地壳或有幔源物质的参与。天河石花岗岩与周边的天河石伟晶岩具有空间、时间和成分上的联系,表明二者具有分异演化上的成因关系。将军山天河石花岗岩类型以及天河石伟晶岩矿物组合指示伟晶岩属于NYF族(富Nb、Y、F)。天河石花岗岩与伟晶岩都显示出Rb的矿化,矿石矿物主要为天河石和多硅白云母。从花岗岩到伟晶岩,天河石和云母中的Rb逐步富集。岩浆高度分异是天河石花岗岩Rb富集的主要机制,但新生地壳物源或幔源物质的加入从源区上限制了Rb的矿化程度。除天河石花岗岩以外,阿尔泰未来的Rb资源勘查应同时关注稀有金属伟晶岩中的钾长石和云母类矿物。

关键词：天河石花岗岩伟晶岩岩石成因阿尔泰

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Rotation curve of the Galactic outer disk derived from radial velocities and uCAC3 proper motions of carbon stars

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Research in Astronomy and Astrophysics 2010年第6期10卷 541-552页

作者： Jia-Cheng l.u zi Zhu Department of Astronomy Nanjing University Nanjing 210093 China Key laboratory of Modem Astronomy and Astrophysics （Nanjing university） Ministry of Education Nanjing 210093 China

The availability of astrometfic data and radial velocities of carbon stars near the Galactic plane enables us to investigate the kinematics of the Milky Way, especially the rotation curve. The recently published Third u. S. Naval Observatory CCD Astrograph Catalog （uCAC3） provides the opportunity to test this problem using three-dimensional velocity in order to obtain more reliable rotation curves. We intend to study the Galactic rotation curve up to 15 kpc using the radial velocities and proper motions of carbon stars. The motivation for using uCAC3 is to provide high precision proper motions which have hardly been used in determining the rotation velocity of tracers. Seventy-four carbon stars and carbon-rich Mira variables toward the anti-center direction （90° 〈 l 〈 270°, ｜b｜〈 6°） are picked up from the literature then matched with uCAC3 carbon star candidates to obtain their proper motions. A rigorous geometrical method is employed to compute the rotation velocity of each object. Taking carbon stars as tracers, we find a flat rotation curve of 210 ± 12 kms^-1 assuming R0 = 8.0kpc for the galactocentric distance and V0 = 220kms^-1 for the rotation velocity of the Sun. Due to the uncertainties of distances, the rotation velocities are more dispersed if tangential velocities enter the cal.ulation, compared to those derived from radial velocities only. However, the whole rotation curve shows coherence with previous results. Increasing observation and study of carbon stars would be desirable in order to provide more homogeneous data for the kinematical study of the Galactic disk.

关键词： astrometry -- Galaxy disk -- Galaxy kinematics and dynamics -- stars carbon