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TOUGHENING OF IN SITU SYNTHESIZED MoSi_2-SiC COMPOSITE AT ROOM TEMPERATURE

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Acta Metallurgica Sinica(English Letters) 2002年第3期15卷 317-323页

作者： Z.Q. Sun, L.Q. Zhang, W.Y. Yang, X.W. Fu and J. ZhuThe State Key Laboratory for Advanced Metals and Materials, university of science & technologybeijing, Beijing 100083, ChinaSchool of Material science & Engineering, university of science & Technology Bei The State Key Laboratory for Advanced Metals and Materials University of Science & Technology Beijing School of Material science & Engineering University of Science & Technology Beijing

The in situ synthesized MoSi2-SiC composite is proved to be of higher fracture toughness than the monolithic MoSi2. The TEM and HREM study reveals that the interface between MoSi2/SiC is of direct atomic bonding without any amorphous glassy phase, such the SiO2 structure. Based on the fractography and the observation of crack propagation path from indentation, it is concluded that the toughening of such composite at room temperature can be attributed to the high interfacial binding energy, the refinement of the MoSi2 matrix and the deflection and bridging behavior in the crack propagation.

关键词： MoSi2-SiC composite synthesized in situ fracture toughening at room temperature

Some Aspects of Research on Layered Ceramic Composites in China

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Some Aspects of Research on Layered Ceramic Composites in Ch...

Investigation of Hydriding Properties and Structure of MlNi5-xSnx System

The 3～〔rd〕International Conference on High-Performance Ceramics(CICC-3)（2）

作者： Wen-Bin Cao and Chang-Chun GeLaboratory of Special Ceramics and Powder Metallurgy university of science and technologybeijing Beijing 100083 China

＜正＞ Layered structure can greatly improve the toughness of the ceramics. Manufacture techniques, including matrixes and interlayer materials choosing and matching, structure and interface design, parameter deciding... 详细信息

关键词： Layered ceramics composite Residual thermal stress Laminates

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Investigation of Hydriding Properties and Structure of MlNi5...

中国政治经济学年度发展报告（2023）（下）

第四届国际稀土学术会议

作者： Lin Qin Song Bo Zhao Shuang Zhu Dajian Zhang MeiDepartment of Physical chemistry university of science and technologybeijing Beijing 100083 China

＜正＞ The hydriding performance, electrochemical properties and structure of MINi5-xSnx（x =0-0.5）hydrogen storage alloys were investigated . The substitution of Ni by Sn leads to an increase of the unit cell volume and charge-discharge cycle life and decrease of the plateau pressure ,hysteresis and the hydrogen storage capacity. The standard enthalpy of hydride formation decreases with increasing tin substitution. The main factor which influences the standard enthalpy of the hydriding reaction is the number of the outer orbit electrons and not the atomic size factor. With a small amount of tin substitution, the cycle life increases by 52% （0.5C） and 42% （1.0C）, but maximum discharge capacity decreases only by 3.0% and 3.5% respectively. The cycle life is obviously improved by the low volume expansion and formed SnO2 Surface layers upon electrochemical cycling.

关键词： hydrogen storage alloy MlNi5-xSnx Electrochemical properties structure

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政治经济学评论 2024年第3期 90+207-208页

作者： Center for Studies of Contemporary Political Economy,Research Institute for 21st-Century Marxism,Nankai university·university of Chinese Academy of Social science Center for Teaching and Research on Capital,Renmin university of China National Institute of Socialist Political Economy with Chinese Characteristics,Renmin university of China 南开大学·中国社会科学院大学21世纪马克思主义研究院当代政治经济学研究中心中国人民大学《资本论》教学与研究中心中国人民大学全国中国特色社会主义政治经济学研究中心

编者按2023年，高质量发展扎实推进，新质生产力加快形成，我国经济总体回升向好，圆满实现发展主要预期目标。为针对性地破解经济恢复发展中的难题，聚焦推进中国式现代化进程中的重点、难点问题，中国政治经济学界开展系统深入研究，...

编者按2023年，高质量发展扎实推进，新质生产力加快形成，我国经济总体回升向好，圆满实现发展主要预期目标。为针对性地破解经济恢复发展中的难题，聚焦推进中国式现代化进程中的重点、难点问题，中国政治经济学界开展系统深入研究，取得系列代表性成果。为准确刻画学界研究进展和轨迹，推动中国经济学理论体系的构建和完善，本刊精选议题如期奉上《中国政治经济学年度发展报告（2023）》。自2010年起，本刊连续十四年发布《中国政治经济学年度发展报告》，“年度发展报告”专栏已成为本刊标志性特色栏目。2023年报告聚焦12个专题，分为（上）（下）两篇，其中专题1—6于报告（上）篇刊登，专题7—12由报告（下）篇刊登。2023年报告（下）选题如下：

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CORRELATION BETWEEN STRESS COMPONENTS AND STRESS CORROSION CRACKS IN BRASS Lecturer,Department of Materials Physics,university of science and Technology Beijing,Beijing 100083,China

同方期刊数据库人大复印报刊资料评论

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Acta Metallurgica Sinica(English Letters) 1992年第9期5卷 178-182页

作者： QIAO Lijie LIU Rui XIAO Jimei university of science and Technology Beijing,Beijing,China

The effects of stress components on nucleation sites and propagation directions of stress cor- rosion cracks in brass were investigated with specimens under mode Ⅱ and mode Ⅲ loadings. The results indicated that under mode Ⅱ loading,stress corrosion cracks nucleated on the site with maximum normal stress component and propagated along the plane perpendieular to the maximum normal stress,under mode Ⅲ loading,the stress corrosion crack was not evident on the 45°plane due to the general corrosion in aqueous solution with high NH_4OH concentra- tion,while stress corroded in aqueous solution with low NH_4OH concentration, numerous cracks with spacings of 10—150μm were found on the 45°plane with maximum normal stress and no stress corrosion cracks was observed on the plane with maximum shear stress.

关键词： stress corrosion cracking stress compoonent brass ammonia solution

Study on Green Residential Space Design

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IJLAI Transactions on Science and Engineering

IJLAI Transactions on science and Engineering 2024年第1期2卷 32-37页

作者： Yu Jiang Shenyang Normal university No.253 Huanghe North Street Shenyang 110034China

With the ever-changing nature,green ecology has become an international trend of ***,the green ecological design of residential space has become the main melody of people’s *** always implement the concept of ecological and environmental protection in the design process,attach importance to the ecological effect of residential space,carry out reasonable budget and use of environmentally friendly decorative materials,reduce the waste of materials,save money and save resources at the same time,and protect the *** the same time,people began to put their hopes on the residential space design,which made the green residential space design began to *** the bold exploration and practice of designers,the design of green residential space will be endowed with more distinctive characteristics and unique *** from the concept of green design,this paper explores the method of green space design through typical analysis.

关键词： Green Residential space Haze

Theorems for Testing Local Activity of CNN and Application to Cardiac Purkinje Equations

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 139-146页

作者： Lequan Min(Applied science School, university of science and Technology Beijing, Beijing 100083, China) Applied science School University of Science and Technology Beijing Beijing 100083 China

The theorems for testing the local in one-port cellular neural/inear network (CNN) cells with four local state variables are presented. Using the theorems computes the bifurcation diagrams of the cardiac Purkinje fiber (CPE) equations Which describethe long-lasting action and pace-maker potentials of the Purkinje fiber of the heart. The computer simulation shows that periodic trajectories or convergent trajectories of the CPF Equations can be foun if the cormsponing cell Parameters are located in a positive domainbut nearby edge of chaos. In particular a heart with approximate normal frequency of heartbeat but non-normal electrocardiogram maysuddenly stop by slightly perturbing the parameters of the corresponding CPF Equations when the Paramders are located nearby the edge of chaos in the bifurcation diagrams. This research seems to interpret reasonbly the phenomena that patients with cardiac diseases might suddenly die without warning.

关键词： cellular neural network local activity cardiac Purkinje fiber heartbeat

SOLIDIFICATION PROCESSING AND FRACTURE MORPHOLOGY OF SiCp/ZL108 COMPOSITE

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Chinese Journal of Mechanical Engineering 1998年第1期11卷 70-75页

作者： Zhao Yutao Jiangsu university of science and Technology Jiangsu Univ of science and Technology Jiangsu China

The solidification processing of SiCp/ZL108 composite material developed by mechanical stirring molten matrix alloy containing flux treated SiC particles is studied. The criterion and model of particles well distributed in matrix are discussed. The bonding structure of interface between SiC particles and ZL108 matrix and the morphology of tensile fracture are analysed by using JXA-840A electron-probe. The mechanism of crack propagating is explored preliminarily.

关键词： Solidification Fracture Morphology Composite

EXPERIMENTAL STUDY ON TRIBOLOGICAL PROPERTIES OF FULLERENE COPOLYMER NANOBALL

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Chinese Journal of Mechanical Engineering 2000年第3期13卷 201-205页

作者： Lei Hong (School of Mechanical science and Engineering, Huazhong university of science and Technology) Guan Wenchao, Liao Daoxun (Huazhong university of science and Technology) 华中科技大学湖北武汉

A novel fullerene-styrene-maleic anhydride copolymer is reported. TEM analyses shows it is water- soluble nanoball of average diameter of about 83 nm. The tribological behavior is evaluated by foul-ball machine. It was found that addition of fullerene copolymer to base stock (2%triethanolamine aqueous solution)resulted in a raise in load-carrying ability(F value)from 130 N to maximum 480 N, and a reduction in coefficient of friction from 0.235 to minimum 0. 063. SEM analyses indicates that the wear scare obtained with fullerene copolymer exhibited mild scratches, while sharp grooving and serious pull-out phenomnon were observed in the presence of base stock without additive .The improvements in friction, wear and load-carrying capacity are probably due to the presence of fullerene copolymer nanoballs, which may act as molecule ball bearings, which in turn lead to elastic rolling lubrication.

关键词： Water-soluble Fullerene copolymer Nanoball Fricition and wear Microcosmic elastic rolling8