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国际医学放射学杂志 2024年第3期 376-377页

作者： Z.Xie S.Suo W.Zhang q.Zhang y.Dai y.Song 余翔玲

摘要目的评估和分析基于平扫和对比增强不同期相CT的影像组学模型，以预测经病理证实的胃肠道间质瘤（gIST）病人的Ki-67增殖指数（PI）。方法将383例经病理

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公元241~1912年中国河西走廊地区年际干湿变化与游牧战争的关系

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中国科学：地球科学 2024年第6期54卷 1950-1959页

作者：唐飞史志林田沁花杜小刚张永中国科学院地理科学与资源研究所陆地表层格局与模拟院重点实验室北京100101 兰州大学敦煌学研究所兰州730020 中国气象局国家气候中心北京100081 甘肃祁连山国家级自然保护区管护中心隆畅河自然保护站张掖734400 中国科学院大学北京100049

长期以来,气候与战争之间的关系一直是一个备受关注的科学和社会问题.在本研究中,探讨了公元241年以来中国河西走廊地区气候与战争爆发的可能关联.基于河西走廊地区树轮资料以及历史时期游牧战争数据,利用时序叠加分析方法,我们发现河... 详细信息

长期以来,气候与战争之间的关系一直是一个备受关注的科学和社会问题.在本研究中,探讨了公元241年以来中国河西走廊地区气候与战争爆发的可能关联.基于河西走廊地区树轮资料以及历史时期游牧战争数据,利用时序叠加分析方法,我们发现河西走廊地区年际干湿变化与游牧民族发动的战争之间存在明显的相关性,但是这种关系是动态的,并与该地区的政权格局有关.在河西走廊存在多个地方政权统治的时期,战争往往随着干旱的气候条件而发生,这可能是由于这些时期的异常干旱加剧了对资源和土地的争夺.相反,在统一王朝管理时期,气候湿润时更容易发生战争,因为牧场的扩大和资源的积累有助于游牧民族的对外征服.这些发现凸显了战争与气候变化之间关系的复杂性.为了更加全面地分析二者之间的关系,需要在更多地区建立覆盖范围更广、分布更均匀且连续的高分辨率历史温湿数据集.此外,对于具有独特特征的区域,需要收集更多的历史战争数据,进行分类讨论研究.

关键词：干旱年际干湿变化战争河西走廊树轮游牧民族

Nonlinear corrections for the nuclear gluon distribution in eA processes

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Chinese Physics C 2024年第3期48卷 52-64页

作者： g.R.Boroun B.Rezaei F.Abdi Department of Physics Razi UniversityKermanshah 67149Iran.

An analytical study with respect to the nonlinear corrections for the nuclear gluon distribution function in the next-to-leading order approximation at small x is *** consider the nonlinear corrections to the nuclear gluon distribution functions at low values of x and q^(2) using the parametrization F_(2)(x,q^(2))and the nuclear modification factors obtained from the Khanpour-Soleymaninia-Atashbar-Spiesberger-guzey *** CT18 gluon distribution is used for the baseline proton gluon density at q^(2)_(0)=*** discuss the behavior of the gluon densities in the next-to-leading order and the next-to-next-to-leading order approximations at the initial scale q^(2)_(0),as well as the modifications due to the nonlinear *** find that the qCD nonlinear corrections are more significant for the next-to-leading order accuracy than the next-to-next-to-leading order for light and heavy *** results of the nonlinear gLR-Mq evolution equation are similar to those obtained with the Rausch-guzey-Klasen gluon upward and downward evolutions within the *** magnitude of the gluon distribution with the nonlinear corrections increases with a decrease in x and an increase in atomic number A.

关键词： gluon distribution nonlinear corrections light and heavy nuclei low x physics

顾颉刚的边疆史地研究:个人情爱与民族情感的交汇

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社会科学研究 2024年第2期 173-185页

作者：王晴佳美国罗文大学历史系新泽西州葛拉斯堡罗08028-2235

九一八事变之后,顾颉刚的学术生涯出现了一个新的面向,从之前专注上古历史的考证、辨伪转而从事研究中国的历史疆域和边疆民族。1934年《禹贡半月刊》的出版和禹贡学会的成立,便是一个标志。顾颉刚本人指出此乃中日关系恶化、民族危机... 详细信息

九一八事变之后,顾颉刚的学术生涯出现了一个新的面向,从之前专注上古历史的考证、辨伪转而从事研究中国的历史疆域和边疆民族。1934年《禹贡半月刊》的出版和禹贡学会的成立,便是一个标志。顾颉刚本人指出此乃中日关系恶化、民族危机深重所致,但从他当时留下的日记和书信,又可以看出他之从事边疆史地的研究,与他长期爱慕谭慕愚(又名谭惕吾)有着密切的关系。谭慕愚的爱国热忱和行动是促使顾颉刚学术兴趣转向的重要契机,而且顾颉刚与谭慕愚的来往还间接地影响了顾颉刚的古史研究。探讨顾颉刚、谭慕愚及殷履安(顾颉刚妻子)之间的三角关系不仅呈现了顾颉刚学术生涯中民族情感和个人情爱的交互作用,而且有助于展现五四学人婚恋和情感生活的复杂和多面,为从情感史的角度考察中国近代学术变迁提供了一个实例。

关键词：顾颉刚谭慕愚(谭惕吾) 殷履安《禹贡》和禹贡学会边疆史地情感史

LoW CyCLE FATIgUE AND DEFoRMATIoN BEHAVIoR IN AN 8090 Al-Li ALLoy

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Acta Metallurgica Sinica(English Letters) 1998年第1期11卷 1-11页

作者： S.H.Ai y.q.Wu Z.g.Wang y.Zhang Chinese Acad of Sciences Shenyang China

Low cycle fatigue (LCF)tests under different total strain amplitudes have been conducted in order to ascertain the effect of precipitate sizes on LCF behavior of 8090 Al-Li alloy. A constant strain rate of 3×10-3s-1 and symmetrical triangular waveform were employed for all tests. It is found that the cyclic stress response of the alloy varied with the precipitate sizes and strain amplitudes. The materials in all conditions cyclically handen at first and the higher the strain amplitude, the greater the amount of hardening. The low cyclic flow stress is the highest in the peakaged condition. TEM and SEM observations demonstrated that cyclic stress-strain behavior and fracture mode of Al-Li alloy are closely related to an increase in the dislocation density and interaction between the precipitates and dislocations, sizes of δ particles and pricipitate free zone (PFZ) at grain boundaries.

关键词： Al-Li alloy low cycle fatigue aged condition

Numerical Simulation of Electroosmotic Flow near Earthworm Surface

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Journal of Bionic Engineering 2006年第4期3卷 179-186页

作者： y.q. Zu y.y. yan School of the Built Environment The University of Nottingham Nottingham NG7 2RD UK

The electroosmotic flow near an earthworm surface is simulated numerically to further understand the anti soil adhesion mechanism of earthworm. A lattice Poisson method is employed to solve electric potential and charge .distributiorts in the electric double layer along the earthworm surface. The external electric field is obtained by solving a Laplace equation. The electroosmotic flow controlled by the Navier-Stokes equations with external body force is simulated by the lattice Boltzmann method. A benchmark test shows that accurate electric potential distributions can be obtained by the LPM. The simulation shows that the moving vortices, which probably contribute to anti soil adhesion, are formed near earthworm body surface by the nonuniform and variational electrical force.

关键词： electroosmotic flow earthworm anti-adhesion LBM EDL

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历史和记忆的分与合:一个观念史的分析

华中师范大学学报（人文社会科学版） 2024年第1期63卷 111-120页

作者：王晴佳上海外国语大学全球文明史研究所上海200083 美国罗文大学历史系新泽西州08028

随着记忆研究在近年的兴起,中文学界出现了“历史记忆”这一名称,含有将两者等同的意思。与之相对照,历史和记忆在西方学术中一直存在某种张力——史学在西方的诞生与对抗记忆的目的相关,之后历史和记忆长期处于一种分离的关系。以兰克... 详细信息

随着记忆研究在近年的兴起,中文学界出现了“历史记忆”这一名称,含有将两者等同的意思。与之相对照,历史和记忆在西方学术中一直存在某种张力——史学在西方的诞生与对抗记忆的目的相关,之后历史和记忆长期处于一种分离的关系。以兰克为代表的近代科学史学,其理论前提是区别“过去”与“现在”,并从后者的立场考察、重构前者,而记忆则常常将两者混为一体。二战之后,兰克史学面临一系列挑战,记忆研究的兴盛便是其中之一。从莫里斯·阿布瓦赫写作《集体记忆》到皮埃尔·诺拉主编《记忆之场》,西方学者试图用记忆来补充和修正历史研究和书写的传统,改进和扩大历史学的方法和范围,促成其内容的更新和革新。但历史研究和记忆研究在近年的合流,仍没有改变两者之间的根本差异。

关键词：近代史学记忆研究历史记忆《记忆之场》莫里斯·阿布瓦赫皮埃尔·诺拉

An insight into Mg alloying effects on Cu thin films:microstructural evolution and mechanical behavior

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Journal of Materials Science & Technology 2020年第22期54卷 101-112页

作者： g.y.Li L.F.Cao J.y.Zhang X.g.Li y.q.Wang K.Wu g.Liu J.Sun State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong UniversityXi'an710049China International Joint Laboratory for Light Alloys(Ministry of Education) College of Materials Science and EngineeringChongqing UniversityChongqing400044China Electron Microscopy Center of Chongqing University Chongqing UniversityChongqing400044China

How to design ultra-strong,light-weight Cu alloys is a long-term pursuit in materials community,which is technically superior and cost-effective for their promising energy-saving *** this work,we prepared Cu-Mg alloyed thin films to study light element Mg alloying effects on the microstructure,hardness and strain rate sensitivity(SRS) of nanocrystalline Cu thin *** the studied Mg concentrationrange spanning from 0 at.% to 16.8 at.%,both the grain size and the twin spacing decrease monotonously with increasing Mg composition while Cu-2.8 at.% Mg sample has the highest twin fraction of ~75%.A combined strengthening model was employed to quantify the Mg concentration-dependent hardness of nanotwinned(NT) Cu-Mg thin films,in which the grain/twin boundary facilitates strengthening while the solute Mg atoms induce *** the constant rate of loading tests and the nanoindentation creep tests uncover that compared with pure Cu samples,the NT Cu-Mg thin films manifest much lower SRS,particularly in the creep tests,owing to the activation of dynamic strain aging effects.

关键词： Cu-Mg thin films Microstructure evolution Creep tests Hardness Strain rate sensitivity

TENSILE STRESS RELAXATIoN oF TURBINE BoLT STEELS AT HIgH TEMPERATURE

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 542-547页

作者： g.q.Jia H.W.Shen y.M.Zhu Metallurgical Department. Shanghai Turbine Company Ltd. Shanghai 200240 ChinaMetallurgical Department. Shanghai Turbine Company Ltd. Shanghai 200240 ChinaMetallurgical Department. Shanghai Turbine Company Ltd. Shanghai 200240 China

Stress relaxation behavior of two turbine bolt steels was evaluated by the manual-controlled tensile stress relaxation test (TSRT) at high temperature. First, feasibility and the procedure of the manual-controlled tensile stress relaxation test (TSRT) is discussed and carried out on a general creep testing machine. And then, the experimental results from such type of test were compared to the existing data provided by certain Laboratory U.K. overall good agreement between the results of manual-controlled TSRT method and the existing data provides confidence in the use of the proposed method in practice. Finally, the experimental results of turbine bolt steels from TSRT were compared with that of bending test. It is observed that great difference exists between the results from two different type stress relaxation tests. It is therefore suggested that the results from TSRT method be adopted in turbine bolt design in engineering.

关键词： tensile stress-relaxation test bending stress-relaxation test turbine bolt steels

AN INVESTIgATIoN oF HIgH-TEMPERATURE DEFoRMATIoN STRENgTHENINg AND ToUgHENINg MECHANISM oF TITANIUM ALLoy

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Acta Metallurgica Sinica(English Letters) 1998年第5期11卷 376-382页

作者： y.g.Zhou W.D.Zing H.q.yu Northwestern Polytechnical Univ Xi'an China

The high-temperature deformation strengthening and toughening mechanisms of titanium alloys have been investigated in this paper. The materials processed by this method produce a new tri-modal microstrvcture, which consists of 10-20% equiaxed alpha, streaky alpha and transformed beta matrix. It is found that the higher ductility of tri-modal microstructure is attributed to the equiaxed alpha's coopemtive slip and coordinated deformation with the transformed beta matrix. The streaky alpha phases not only increase the strength and creep properties, but also increase the fracture toughness. Propagating along grain boundaries between two neighboring streaky alpha phases, cracks in tri-modal microstructure make a more tortuous way, and then the materials show a higher fracture toughness. This new method is applicable to α, near α,α+β and near β titanium alloys.

关键词： titanium alloy high-temperature deformation strengthening and toughening mechanism