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    题名 作者 年代 出处 被引量
1秦-祁-昆造山带元古宙副变质岩层碎屑锆石年龄谱研究显示文摘根据秦-祁-昆造山带中北大河岩群、湟源岩群、化隆岩群、金水口岩群、陡岭岩群和秦岭岩群等副变质岩层碎屑锆石年龄谱资料,这些原定为古元古代的地层,至少包括测年样品在内的部分地层的时代应属中元古代或新元古代初期。研究资料还显示上述碎屑岩层具有大量中元古代早期的物源,而古元古代蚀源物质较匮乏。因此,上述副变质岩层显示出相近的碎屑锆石年龄谱特征。陆松年 李怀坤 王惠初 陈志宏 郑健康 相振群 2009岩石学报2009,25,9:77
2分子模拟方法及模拟软件Materials Studio在高分子材料中的应用显示文摘综述分子模拟的发展历史、分子模拟在高分子材料发展中的意义。介绍用于分子模拟计算的4种模拟方法:量子力学从头算方法、分子力学方法、分子动力学方法和蒙特卡罗方法。简单介绍常见的分子模拟软件,重点介绍Materials Studio在研究高分子材料的共混性,相容性,力学性能方面的应用。庄昌清 岳红 张慧军 2010塑料2010,39,4:36
3MR with Gd-EOB-DTPA in assessment of liver nodules in cirrhotic patients显示文摘To date the imaging diagnosis of liver lesions is based mainly on the identification of vascular features, which are typical of overt hepatocellular carcinoma(HCC), but the hepatocarcinogenesis is a complex and multistep event during which, a spectrum of nodules develop within the liver parenchyma, including benign small and large regenerative nodule(RN), low-grade dysplastic nodule(LGDN), high-grade dysplastic nodule(HGDN), early HCC, and well differentiated HCC. These nodules may be characterised not only on the basis of their respective different blood supplies, but also on their different hepatocyte function. Recently, in liver imaging the introduction of hepatobiliary magnetic resonance imaging contrast agent offered the clinicians the possibility to obtain, at once, information not only related to the vascular changes of liver nodules but also information on hepatocyte function. For this reasons this new approach becomes the most relevant diagnostic clue for differentiating low-risk nodules(LGDN-RN) from highrisk nodules(HGDN/early HCC or overt HCC) and consequently new diagnostic algorithms for HCC have been proposed. The use of hepatobiliary contrast agents is constantly increasing and gradually changing the standard of diagnosis of HCC. The main purpose of this review is to underline the added value of Gd-EOB-DTPA in early-stage diagnoses of HCC. We also analyse the guidelines for the diagnosis and management of HCC, the key concepts of HCC development, growth and spread and the imaging appearance of precursor nodules that eventually may transform into overt HCC.Riccardo Inchingolo Riccardo Faletti Luigi Grazioli Eleonora Tricarico Marco Gatti Anna Pecorelli Davide Ippolito 2018World Journal of Hepatology2018,10,7:37
4A review on machinability of carbon fiber reinforced polymer(CFRP)and glass fiber reinforced polymer(GFRP)composite materials显示文摘Fiber reinforced polymer(FRP) composite materials are heterogeneous and anisotropic materials that do not exhibit plastic deformation. They have been used in a wide range of contemporary applications particularly in space and aviation,automotive,maritime and manufacturing of sports equipment. Carbon fiber reinforced polymer(CFRP) and glass fiber reinforced polymer(GFRP) composite materials,among other fiber reinforced materials,have been increasingly replacing conventional materials with their excellent strength and low specific weight properties. Their manufacturability in varying combinations with customized strength properties,also their high fatigue,toughness and high temperature wear and oxidation resistance capabilities render these materials an excellent choice in engineering applications.In the present review study,a literature survey was conducted on the machinability properties and related approaches for CFRP and GFRP composite materials. As in the machining of all anisotropic and heterogeneous materials,failure mechanisms were also reported in the machining of CFRP and GFRP materials with both conventional and modern manufacturing methods and the results of these studies were obtained by use of variance analysis(ANOVA),artificial neural networks(ANN) model,fuzzy inference system(FIS),harmony search(HS) algorithm,genetic algorithm(GA),Taguchi's optimization technique,multi-criteria optimization,analytical modeling,stress analysis,finite elements method(FEM),data analysis,and linear regression technique. Failure mechanisms and surface quality is discussed with the help of optical and scanning electron microscopy,and profilometry. ANOVA,GA,FEM,etc. are used to analyze and generate predictive models.Meltem Altin Karatas Hasan Gokkaya 2018Defence Technology(防务技术)2018,14,4:31
5内蒙古克什克腾旗小东沟斑岩型钼矿床成岩成矿机制探讨显示文摘本文选取内蒙古克什克腾旗的小东沟斑岩型钼矿区作为研究区,它位于西拉沐伦钼矿带的西南部。对小东沟岩体进行了主微量元素、SHRIMP锆石U-Pb定年等地球化学方面的研究;对岩体中的钾长石和含矿矿物辉钼矿进行了普通铅同位素分析。小东沟岩体具有高硅富钾、REE含量低、Zr含量高、无负铕异常、高ε_(Nd)(t)、低Sr_i等特点,指示岩浆起源于加厚新生下地壳的熔融,同时具有高温、快速熔融、快速析离逃离源区的特点;小东沟岩体的SHRIMP锆石U-Pb定年结果为142±2Ma,对应140Ma左右主应力场由南北向转为东西向的构造体制大转折时期,这个时期大兴安岭处于伸展的构造环境下,底侵作用发育,地幔物质可以添加到下地壳熔融形成的岩浆中;对岩体钾长石和辉钼矿进行的普通铅同位素分析显示前者具有从造山带-地幔过渡的特征,后者则显示有地幔特征,说明成岩、成矿物质来自两个不同的源区,下地壳的岩浆和地幔含矿流体发生了混合。通过以上的分析,结合水-岩浆物理反应的实验结果,本文提出小东沟斑岩型钼矿床的成矿模式:大兴安岭地区在早白垩世伸展的构造背景下,地幔含矿流体加入受底侵作用加热的下地壳中使之熔融形成岩浆,随后更多的地幔含矿流体进入岩浆房,促使其迅速析离逃逸出源区,二者一起上升侵位。在岩浆温度较高时,地幔含矿流体和岩浆大致以较稳定的液态不混溶的状态共存;当岩浆和流体侵位到较浅深度时,压力下降,温度降低,晶体增多,流体-岩浆体系变得不稳定,岩浆被流体分割成许多很小的岩浆团。流体中H^+、K^+和各种成矿元素的存在使之必然会和岩浆或冷却后形成的岩石发生蚀变反应,并晶出成矿矿物,形成现在我们看到的具有浸染状矿化现象的小东沟斑岩型钼矿床。覃锋 刘建明 曾庆栋 罗照华 2009岩石学报2009,25,12:29
6Recent advances in friction and lubrication of graphene and other 2D materials:Mechanisms and applications显示文摘Two-dimensional materials having a layered structure comprise a monolayer or multilayers of atomic thickness and ultra-low shear strength.Their high specific surface area,in-plane strength,weak layer-layer interaction,and surface chemical stability result in remarkably low friction and wear-resisting properties.Thus,2D materials have attracted considerable attention.In recent years,great advances have been made in the scientific research and industrial applications of anti-friction,anti-wear,and lubrication of 2D materials.In this article,the basic nanoscale friction mechanisms of 2D materials including interfacial friction and surface friction mechanisms are summarized.This paper also includes a review of reports on lubrication mechanisms based on the film-formation,self-healing,and ball bearing mechanisms and applications based on lubricant additives,nanoscale lubricating films,and space lubrication materials of 2D materials in detail.Finally,the challenges and potential applications of 2D materials in the field of lubrication were also presented.Lincong LIU Ming ZHOU Long JIN Liangchuan LI Youtang MO Guoshi SU Xiao LI Hongwei ZHU Yu TIAN 2019Friction2019,7,3:29
7界面导热材料研究进展显示文摘综述了导热脂、导热胶黏剂、导热橡胶、导热胶带及相变材料等几类界面导热材料(TIMs)的组成成分、制备方法、主要性能、应用领域及其优化设计方法,并对国内外界面导热材料的发展进行了展望。丁孝均 赵云峰 2010宇航材料工艺2010,40,6:24
8Materials Studio在结构化学教学中的一些应用显示文摘介绍在结构化学教学中,应用分子模拟软件Materials Studio辅助教学的一些具体做法。吴健 2007高校实验室工作研究2007,,3:19
9Body armour-New materials, new systems显示文摘This is a very timely review of body armour materials and systems since new test standards are currently being written, or reviewed, and new, innovative products released. Of greatest importance, however, is the recent evolution, and maturity, of the Ultra High Molecular Weight Polyethylene fibres enabling a completely new style of system to evolve e a stackable system of Hard Armour Plates. The science of body armour materials is quickly reviewed with emphasis upon current understanding of relevant energy-absorbing mechanisms in fibres, fabrics, polymeric laminates and ceramics. The trend in ongoing developments in ballistic fibres is then reviewed, analysed and future projections offered. Weaknesses in some of the ceramic grades are highlighted as is the value of using cladding materials to improve the robustness, and multi-strike performance, of Hard Armour Plates. Finally, with the drive for lighter, and therefore smaller, soft armour systems for military personnel the challenges for armour designers are reported, and the importance of the relative size of the Hard Armour Plate to the Soft Armour Insert is strongly emphasised.Ian G.Crouch 2019Defence Technology(防务技术)2019,15,3:19
10Porphyrin-like Fe-N4 sites with sulfur adjustment on hierarchical porous carbon for different rate-determining steps in oxygen reduction reaction显示文摘We developed a strategy based on coordination polymer to synthesize singleatom site Fe/N and S-codoped hierarchical porous carbon (Fe1/N,S-PC).The as-obtained Fe1/N,S-PC exhibited superior oxygen reduction reaction (ORR) performance with a half-wave potential (Ev2,0.904 V vs.RHE) that was better than that of commercial Pt/C (E1/2,0.86 V vs.RHE),single-atom site Fe/N-doped hierarchical porous carbon (Fe1/N-PC) without S-doped (E1/2,0.85 V vs.RHE),and many other nonprecious metal catalysts in alkaline medium.Moreover,the Fe1/N,S-PC revealed high methanol tolerance and firm stability.The excellent electrocatalytic activity of Fe1/N,S-PC is attributed to the synergistic effects from the atomically dispersed porphyrin-like Fe-N4 active sites,the heteroatom codoping (N and S),and the hierarchical porous structure in the carbon materials.The calculation based on density functional theory further indicates that the catalytic performance of Fe1/N,S-PC is better than that of Fe1/N-PC owing to the sulfur doping that yielded different rate-determining steps.Konglin Wu Xin Chen Shoujie Liu Yuan Pan Weng-Chon Cheong Wei Zhu Xing Cao Rongan Shen Wenxing Chen Jun LUO Wensheng Yan Lirong Zheng Zheng Chen Dingsheng Wang Qing Peng Chen Chen Yadong Li 2018Nano Research2018,11,12:18
11Fluorine-containing oxidizers for metal fuels in energetic formulations显示文摘Fluorine containing oxidizers, primarily polymers, are extensively used in pyrotechnic compositions.Fluorinated oxidizers are less explored for metalized propellants and explosives despite a potential advantage of substantial heat release combined with gaseous combustion products. This review summarizes different types of fluorinated oxidizers used in energetic formulations or of potential interest for such systems, including gases, polymers, and inorganic compounds. Types of energetic formulations employing metals and fluoropolymers are discussed in more detail, including methods used to prepare composites and resulting salient features of the obtained materials. Laboratory experiments characterizing such materials, in particular, electron microscopy and thermal analysis, are discussed, showing characteristic morphologies and reaction sequences observed in different metal-fluorinated oxidizer composites. Striking similarities are noted in reaction sequences for diverse compositions hinting at possible similarities in the respective reaction mechanisms. Experiments probing ignition and combustion of metal-fluorinated oxidizer composites in laboratory conditions are also reviewed, including impact, flash heating and shock ignition. Finally, some practical performance tests for energetic formulations are described following by a brief discussion of the reaction mechanisms expected to govern ignition and combustion in various metal-fluorinated oxidizer composites. The conclusions are combined with recommendation for future research in the area of reactive metal-fluorinated oxidizer composites.Siva Kumar Valluri Mirko Schoenitz Edward Dreizin 2019Defence Technology(防务技术)2019,15,1:17
12Nanostructured thermoelectric materials:Current research and future challengeZhigang Chen Guang Han Lei Yang Lina Cheng Jin Zou 2012Progress in Natural Science:Materials International2012,22,6:17
13Rational design on separators and liquid electrolytes for safer lithium-ion batteries显示文摘As the energy density of lithium-ion batteries (LIBs) continues to increase,their safety has become a great concern for further practical large-scale applications.One of the ultimate solution of the safety issue is to develop intrinsically safe battery components,where the battery separators and liquid electrolytes are critical for the battery thermal runaway process.In this review,we summarize recent progress in the rational materials design on battery separators and liquid electrolyte towards the goal of improving the safety of LIBs.Also,some strategies for further improving safety of LIBs are also briefly outlooked.Mengqi Yuan Kai Liu 2020Journal of Energy Chemistry2020,29,4:16
14Materials Studio和Matlab等软件在化学动力学教学中的应用显示文摘在化学动力学讲授中应用Materials Studio和Matlab等软件对过渡态理论及稳态近似法等相关知识点进行辅助教学,使抽象的化学理论变得形象、简单。这有利于培养学生的形象思维能力,提高了课堂教学效果,激发了学生对物理化学课程的学习兴趣。陈鑫 李彪 姚军 朱元强 2016大学化学2016,31,6:16
15稠油沥青质胶质降粘机理的分子动力学模拟显示文摘为深入了解稠油降粘机理,进一步指导实验室合成路径,利用Materials Studio模拟软件验证了以苯乙烯、丙烯酸十八酯和马来酸酐为原料进行的降粘剂合成在分子动力学上的可行性;探究该降粘剂对沥青质、胶质缔合体系的解固作用,结果表明降粘剂分子凭借长直链和富含酯基、烷基的侧链结构可以有效解除缔合,实现原油降粘;进一步模拟由苯乙烯、丙烯酸十八酯、马来酸酐和丙烯酰胺为原料合成的四元聚合物及其降粘效果,推断出四元聚合物对稠油降粘的效果将优于三元聚合物。因此,该四元降粘聚合物将成为下一步实验室合成的目标产物,M aterials Studio分子动力学模拟在材料合成中将发挥越来越重要的指导作用。崔青 张长桥 修建新 许士明 卢丽丽 2017山东大学学报(工学版)2017,47,2:15
16Porous high entropy(Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2)B2: A novel strategy towards making ultrahigh temperature ceramics thermal insulating显示文摘Transition metal diborides based ultrahigh temperature ceramics(UHTCs) are characterized by high melting point, high strength and hardness, and high electrical and thermal conductivity. The high thermal conductivity arises from both electronic and phonon contributions. Thus electronic and phonon contributions must be controlled simultaneously in reducing the thermal conductivity of transition metal diborides. In high entropy(HE) materials, both electrons and phonons are scattered such that the thermal conductivity can significantly be reduced, which opens a new window to design novel insulating materials. Inspired by the high entropy effect, porous HE(Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2)B2 is designed in this work as a new thermal insulting ultrahigh temperature material and is synthesized by an in-situ thermal borocarbon reduction/partial sintering process. The porous HE(Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2)B2 possesses high porosity of 75.67%, pore size of 0.3–1.2 μm, homogeneous microstructure with small grain size of 400–800 nm, which results in low room temperature thermal diffusivity and thermal conductivity of 0.74 mm2 s^-1 and 0.51 W m^-1K^-1, respectively. In addition, it exhibits high compressive strength of3.93 MPa. The combination of these properties indicates that exploring porous high entropy ceramics such as porous HE(Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2)B2 is a novel strategy in making UHTCs thermal insulating.Heng Chen Huimin Xiang Fu-Zhi Dai Jiachen Liu Yanchun Zhou 2019Journal of Materials Science & Technology2019,35,10:15
17Preparation of 2024/3003 gradient materials by semi-continuous casting using double-stream-pouring technique显示文摘The 2024/3003 aluminum gradient alloys are prepared by semi continuous casting. The influences of throttle bore diameter of embedded nozzle and temperature of internal melt on composition distribution, macrostructure, hardness are analyzed, and the stability of gradient distribution of composition, macrostructure and hardness along the axial direction of the ingot is also studied. The results show that diffe rent composition profiles can be achieved by adjusting the processing parameters; the volume fraction of inner alloy in the ingot can be increased by enlarging the throttle bore diameter and elevating the temperature of inner melt; quasi steady solidification can be realized within 20 s during cast processing, and consistent quality ingot is obtained by controlling the casting speed and liquid height of inner melt.李元元 费劲 陈维平 张卫文 邵明 2002Journal of Central South University of Technology2002,9,4:14
18DIFFUSION COUPLE BETWEEN HIGHSTRENGTH WEAR-RESISTING ALUMINUM BRONZE AND MACHINING TOOLS MATERIALS显示文摘INTRODUCTIONAluminumbronzeisanimportantengineeringmaterial.Itsexcelentphysical,mechanical,anticorosionandwearresistingprop...Li, Yuanyuan Zhang, Datung Ngai Tungwai, Leo Xia, Wei Long, Yan 1999中国有色金属学会会刊:英文版1999,9,1:14
19In vitro corrosion resistance and antibacterial performance of noveltin dioxide-doped calcium phosphate coating on degradable Mg-1Li-1Ca alloy显示文摘A SnO_2-doped calcium phosphate(Ca-P-Sn) coating was constructed on Mg-1 Li-1 Ca alloy by a hydrothermal process. The fabricated functional coatings were investigated using scanning electron microscopy(SEM), X-ray diffraction(XRD) and Fourier transform infrared spectroscopy(FT-IR). A triple-layered structure, which is composed of Ca_3(PO_4)_2,(Ca, Mg)_3(PO_4)_2, SnO_2, and MgHPO_4·3 H_2O, is evident and leads to the formation of Ca_(10)(PO_4)_6(OH)_2 in Hank's solution. Electrochemical measurements, hydrogen evolution tests and plating counts reveal that the corrosion resistance and antibacterial activity were improved through the coating treatment. The embedded SnO_2 nanoparticles enhanced crystallisation of the coating.The formation and degradation mechanisms of the coating were discussed.Lan-Yue Cui Guang-Bin Wei Zhuang-Zhuang Han Rong-Chang Zeng Lei Wang Yu-Hong Zou Shuo-Qi Li Dao-Kui Xu Shao-Kang Guan 2019Journal of Materials Science & Technology2019,35,3:14
20Electrochemical performance of a nickel-rich LiNi0.6Co0.2Mn0.2O2 cathode material for lithium-ion batteries under different cut-off voltages显示文摘A spherical-like Ni_(0.6)Co_(0.2)Mn_(0.2)(OH)_2 precursor was tuned homogeneously to synthesize LiNi_(0.6)Co_(0.2)Mn_(0.2)O_2 as a cathode material for lithium-ion batteries.The effects of calcination temperature on the crystal structure,morphology,and the electrochemical performance of the as-prepared LiNi_(0.6)Co_(0.2)Mn_(0.2)O_2 were investigated in detail.The as-prepared material was characterized by X-ray diffraction,scanning electron microscopy,laser particle size analysis,charge–discharge tests,and cyclic voltammetry measurements.The results show that the spherical-like LiNi_(0.6)Co_(0.2)Mn_(0.2)O_2 material obtained by calcination at 900°C displayed the most significant layered structure among samples calcined at various temperatures,with a particle size of approximately 10 μm.It delivered an initial discharge capacity of 189.2 m Ah×g^(-1) at 0.2C with a capacity retention of 94.0% after 100 cycles between 2.7 and 4.3 V.The as-prepared cathode material also exhibited good rate performance,with a discharge capacity of 119.6 m Ah×g^(-1) at 5C.Furthermore,within the cut-off voltage ranges from 2.7 to 4.3,4.4,and 4.5 V,the initial discharge capacities of the calcined samples were 170.7,180.9,and 192.8 m Ah×g^(-1),respectively,at a rate of 1C.The corresponding retentions were 86.8%,80.3%,and 74.4% after 200 cycles,respectively.Kai-lin Cheng Dao-bin Mu Bo-rong Wu Lei Wang Ying Jiang Rui Wang 2017International Journal of Minerals,Metallurgy and Materials2017,24,3:14
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