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新型主流媒体出镜记者“主播化”路径研究——以《一切为了群众》账号主播“刚子”走红为例 被引量:1
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作者 李京选 王静 《新闻传播》 2023年第22期57-59,共3页
传统新闻报道中,出镜记者发挥着重要作用。媒体融合背景下,越来越多出镜记者向网络主播转型,以此拉近与受众之间的距离,壮大广电媒体网络空间的舆论阵地,这是主流媒体走向深度融合的有效途径。本文通过剖析《一切为了群众》账号出镜记... 传统新闻报道中,出镜记者发挥着重要作用。媒体融合背景下,越来越多出镜记者向网络主播转型,以此拉近与受众之间的距离,壮大广电媒体网络空间的舆论阵地,这是主流媒体走向深度融合的有效途径。本文通过剖析《一切为了群众》账号出镜记者“刚子”的成长之路,从执法行动直播到内容输出,再到“造梗出圈”继而走红,探究出镜记者“主播化”的发展路径和策略,从而为主流媒体记者转型提供参考和借鉴。 展开更多
关键词 媒体融合 出镜记者 主播化 刚子 路径
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Two Steps B Ion-Implantation of Diamond Film Grown on an n-Type Si Substrate and Its p-n Junction Effects
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作者 孙秀平 冯克成 +2 位作者 李超 张红霞 费允杰 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第6期1073-1076,共4页
Polycrystalline diamond thin films are deposited on an n-type Si substrates by hot filament chemical vapor deposition,and then are implanted with boron ions in a 200keV ion implanter.In order to achieve a better distr... Polycrystalline diamond thin films are deposited on an n-type Si substrates by hot filament chemical vapor deposition,and then are implanted with boron ions in a 200keV ion implanter.In order to achieve a better distribution of the implanted element,boron ions are implanted by two steps:implanting boron ions with the energy of 70keV first,and then with the energy of 100keV.The homogeneous distribution of the B ion is gained.The current-voltage characteristics of the samples are studied.It is found that the p-n heterojunction effect is achieved in these samples. 展开更多
关键词 ion implantation diamond film p-n junction
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Properties and microstructure of Cu/diamond composites prepared by spark plasma sintering method 被引量:11
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作者 陶静梅 朱心昆 +2 位作者 田维维 杨鹏 杨浩 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第10期3210-3214,共5页
Cu/diamond composites have been considered as the next generation of thermal management material for electronic packages and heat sinks applications. Cu/diamond composites with different volume fractions of diamond we... Cu/diamond composites have been considered as the next generation of thermal management material for electronic packages and heat sinks applications. Cu/diamond composites with different volume fractions of diamond were successfully prepared by spark plasma sintering(SPS) method. The sintering temperatures and volume fractions(50%, 60% and 70%) of diamond were changed to investigate their effects on the relative density, homogeneity of the microstructure and thermal conductivity of the composites. The results show that the relative density, homogeneity of the microstructure and thermal conductivity of the composites increase with decreasing the diamond volume fraction; the relative density and thermal conductivity of the composites increase with increasing the sintering temperature. The thermal conductivity of the composites is a result of the combined effect of the volume fraction of diamond, the homogeneity and relative density of the composites. 展开更多
关键词 Cu/diamond composites spark plasma sintering relative density thermal conductivity
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Study on the Dielectric Properties of Chemical Vapor Deposited Diamond Film
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作者 汪浩 王秀芬 +1 位作者 郭林 朱鹤孙 《Journal of Beijing Institute of Technology》 EI CAS 1998年第3期274-279,共6页
Aim To study the dielectric properties of diamond film. Methods Dielectric properties (the frequency dependenCe of conductance, permittivity, and loss factor) of diamond film preped by DC are plasma jet chemical vap... Aim To study the dielectric properties of diamond film. Methods Dielectric properties (the frequency dependenCe of conductance, permittivity, and loss factor) of diamond film preped by DC are plasma jet chemical vapor deposition (CVD) were studied. Resuls Dielectric properties of CVD diamond fAn depend mainly on its polycrystalline nature, and the presence of non-diamond disordered graphitic regions and impurities between diamond grains of the film. Annealing at 500℃ leads to the removal of greater part of disordered graphitic regions, but am not remove all disordered graphitic regions and impurities. Conclusion Much work nab to be done tO prepare or post-treat diamond films before using CVD diamond as a substrate for electronic devices. 展开更多
关键词 dielectric properties diamond film DC are plasma jet CVD
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Design of the Composite Steel-Glass Beams with Semi-Rigid Polymer Adhesive Joint 被引量:2
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作者 Michal Netusil Martina Eliasova 《Journal of Civil Engineering and Architecture》 2012年第8期1059-1069,共11页
New and high transparent structural element, steel-glass composite beam was developed in respect to fabrication, static-structural and architectural criteria and consists of steel flanges and glass web assembled toget... New and high transparent structural element, steel-glass composite beam was developed in respect to fabrication, static-structural and architectural criteria and consists of steel flanges and glass web assembled together by semi-rigid polymer adhesive, which is the key element of whole composite system. These beams can be used mainly as members of high transparent roof or floor structure as well as stiffening fins for large area glass facades. This paper deals with experimental research performed at CTU (Czech Technical University) Prague, which started by adhesive selection and initial material tests by ISO527, continued via small-scale steel-glass connection tests and graduated by full-scale tests of hybrid beams with the span of 4 m. Generalized results of these experiments, analytical and numerical studies serve as device, how to accurately predict the behavior of the beam, describe the stress distribution along the cross section and safely and economically design such a kind of structure with semi-rigid shear connection, made by polymer adhesive. 展开更多
关键词 Steel-glass composite beam POLYMER ADHESIVE FE modeling semi-rigid joint.
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A rigidity theorem for submanifolds in S^(n+p) with constant scalar curvature 被引量:8
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作者 张剑锋 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第4期322-328,共7页
Let Mn be a closed submanifold isometrically immersed in a unit sphere Sn . Denote by R, H and S, the normalized +p scalar curvature, the mean curvature, and the square of the length of the second fundamental form of ... Let Mn be a closed submanifold isometrically immersed in a unit sphere Sn . Denote by R, H and S, the normalized +p scalar curvature, the mean curvature, and the square of the length of the second fundamental form of Mn, respectively. Suppose R is constant and ≥1. We study the pinching problem on S and prove a rigidity theorem for Mn immersed in Sn +pwith parallel nor- malized mean curvature vector field. When n≥8 or, n=7 and p≤2, the pinching constant is best. 展开更多
关键词 Scalar curvature Mean curvature vector The second fundamental form
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Bifurcation of Periodic Motion of Rigid Rotor System Supported by Angular Contact Ball Bearings
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作者 崔立 刘长利 郑建荣 《Transactions of Tianjin University》 EI CAS 2011年第6期404-410,共7页
Rotor systems supported by angular contact ball bearings are complicated due to nonlinear Hertzian contact force. In this paper, nonlinear bearing forces of ball bearing under five-dimensional loads are given, and 5-D... Rotor systems supported by angular contact ball bearings are complicated due to nonlinear Hertzian contact force. In this paper, nonlinear bearing forces of ball bearing under five-dimensional loads are given, and 5-DOF dynamic equations of a rigid rotor ball bearing system are established. Continuation-shooting algorithm for periodic solutions of the nonlinear non-autonomous dynamic system and Floquet multipliers of the system are used. Furthermore, the bifurcation and stability of the periodic motion of the system in different parametric domains are also studied. Results show that the bifurcation and stability of period-1 motion vary with structural parameters and operating parameters of the rigid rotor ball bearing system. Avoidance of unbalanced force and bending moment, appropriate initial contact angle, axial load and damping factor help enhance the unstable rotating speed of period-1 motion. 展开更多
关键词 angular contact ball bearing rigid rotor system BIFURCATION periodic motion continuation-shooting algorithm
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Studies of Rigid Rotor-Rigid Surface Scattering in Dynamical Lie Algebraic Method
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作者 WANGXiao-Yan DINGShi-Liang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第3期357-361,共5页
The dynamical Lie algebraic method is used for the description of statistical mechanics of rotationally inelastic molecule-surface scattering. It can give the time-evolution operators about the low power of and by s... The dynamical Lie algebraic method is used for the description of statistical mechanics of rotationally inelastic molecule-surface scattering. It can give the time-evolution operators about the low power of and by solving a set of coupled nonlinear differential equations. For considering the contribution of the high power of and , we use the Magnus formula. Thus, with the time-evolution operators we can get the statistical average values of the measurable quantities in terms of the density operator formalism in statistical mechanics. The method is applied to the scattering of (rigid rotor) by a flat, rigid surface to illustrate its general procedure. The results demonstrate that the method is useful for describing the statistical dynamics of gas-surface scattering. 展开更多
关键词 Lie algebraic method SCATTERING rigid rotor
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Preparation of β-Sialon/ZrN bonded corundum composites from zircon by nitridation reaction sintering process 被引量:3
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作者 马北越 于景坤 +1 位作者 刘涛 颜正国 《Journal of Central South University》 SCIE EI CAS 2009年第5期725-729,共5页
β-Sialon/ZrN bonded corundum composites were synthesized using fused white corundum,alumina micro powder,zircon and carbon black by nitridation reaction sintering process. Phase composition and microstructure of the ... β-Sialon/ZrN bonded corundum composites were synthesized using fused white corundum,alumina micro powder,zircon and carbon black by nitridation reaction sintering process. Phase composition and microstructure of the synthesized composites were investigated by X-ray powder diffraction and scanning electronic microscope,and the formation process of the composites was discussed. The results show that the composites with different compositions can be obtained by controlling the heating temperature and contents of zircon and carbon black. The proper temperature to synthesize the composites is 1773 K. 展开更多
关键词 Β-SIALON ZRN ZIRCON CORUNDUM COMPOSITES nitridation reaction sintering process
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Micro-structure of PECVD Diamond Films by Slow Positron Beam
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作者 Yan Xu Hui-min Weng +6 位作者 Bang-jiao Ye Hai-yun Wang Cheng-xiao Peng Chuan-ying Xi Bin Cheng Xian-yi Zhou Rong-dian Han 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第4期291-293,共3页
The microstructure of diamond films was studied by slow positron beam and Raman spectroscopy. For the Raman spectroscopy experiment on diamond films, a high fraction of the sp3 hybridized bond was detected in samples.... The microstructure of diamond films was studied by slow positron beam and Raman spectroscopy. For the Raman spectroscopy experiment on diamond films, a high fraction of the sp3 hybridized bond was detected in samples. Positron annihilation spectra analysis further illuminated that the concentration and types of defects were different in each sample. S-E curves of all samples showed that diamond crystal structures had obvious variation in each sample. These results indicated that positron annihilation spectroscopy was an effective means to measure microstructure of diamond films. 展开更多
关键词 Diamond film DEFECT Slow positron DIFFUSION
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Effect of heating time on bonding interface, atom diffusion and mechanical properties of dissimilar titanium joints produced by thermal self-compressing bonding 被引量:7
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作者 Yun-hua DENG Qiao GUAN Jun TAO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第4期662-668,共7页
Solid-state bonding between pure titanium and Ti6Al4V(TC4)alloy was conducted by a new bonding method named as rigid restraint thermal self-compressing bonding.Effects of heating time on bonding interface,atom diffusi... Solid-state bonding between pure titanium and Ti6Al4V(TC4)alloy was conducted by a new bonding method named as rigid restraint thermal self-compressing bonding.Effects of heating time on bonding interface,atom diffusion and mechanical properties of the joints were studied.Results show that atom diffusion between pure titanium and TC4 alloy significantly takes place during bonding.The diffusion depths of Al and V in pure titanium side are increased with increasing heating time.Due to the enhancement of atom diffusion,bond quality of the bonding interface is improved along with the increase of heating time.The heating time seems to have little effect on microhardness distribution across the joint.However,the tensile strength and ductility of the joint have close relation to heating time.Prolonging heating time can improve the tensile strength and ductility of the joint,especially the latter.When the heating time increases to 450 s,solid-state joint with good combination of strength and ductility is attained. 展开更多
关键词 dissimilar titanium alloys joining rigid restraint thermal self-compressing bonding atom diffusion mechanical properties
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Improving behavior of semi-supported steel plate shear walls
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作者 Ali GHAMARI Abbas AKBARPOUR Ali GHANBARI 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第10期2891-2905,共15页
In spite of the good performance of the steel plate shear wall(SPSW)in recent earthquakes and experimental studies,the need for huge columns to surround the infill plate is a major shortcoming of the system.This short... In spite of the good performance of the steel plate shear wall(SPSW)in recent earthquakes and experimental studies,the need for huge columns to surround the infill plate is a major shortcoming of the system.This shortcoming can be resolved by using semi-supported SPSW.The semi-supported SPSW has secondary columns that prevent the transfer of stress from the infill plate to the main columns.In spite of extensive experimental and numerical investigations on SPSWs,there are many ambiguities regarding the behavior of the semi-supported SPSW.Although stress in the columns is reduced,incomplete diagonal tension field action is formed in the infill plate that creates new problems.In this paper,a new type of semi-supported SPSW is presented in which the steel plate and the secondary columns are angled.The creation of the angle of the plate and the secondary column makes it possible to use the full capacity of the steel plate as well as the capacity of the secondary columns.Numerical results showed that the wall with a 60°angle has a favorable performance relative to the semi-supported wall.Moreover,with the 60°angle,stiffness,strength and energy absorption is increased.The angle of the secondary columns has little effect on the non-elastic stiffness.Nevertheless,using a wall with an angle of more than 90°can neutralize the wall’s behavior relative to conventional walls.Therefore,the wall with a 60°angle as an optimal angle is recommended. 展开更多
关键词 steel plate shear wall(SPSW) DUCTILITY STIFFNESS ultimate strength R factor
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Deposition of diamond like carbon films by using a single ion gun with varying beam source
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作者 姜金球 陈祝平 《Journal of Coal Science & Engineering(China)》 2001年第1期80-83,共4页
Diamond like carbon films have been successfully deposited on the steel substrate, by using a single ion gun with varying beam source. The films may appear blue, yellow and transparent in color, which was found relate... Diamond like carbon films have been successfully deposited on the steel substrate, by using a single ion gun with varying beam source. The films may appear blue, yellow and transparent in color, which was found related to contaminants from the sample holder and could be avoided. The thickness of the films ranges from tens up to 200 nanometers, and the hardness is in the range 20 to 30 GPa. Raman analytical results reveal the films are in amorphous structure. The effects of different beam source on the films structure are further discussed. 展开更多
关键词 ion beam deposition diamondlike carbon thin film beam source primary process
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Ti-containing hydrogenated carbon films fabricated by high-power plasma magnetron sputtering 被引量:4
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作者 YANG Peng SUNG Chia-chi +2 位作者 FUH Yiin-Kuen CHU Chun-lin LO Chih-hung 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第6期1381-1386,共6页
To improve the characteristics of a diamond-like carbon (DLC) film, Ti-containing amorphous hydrogenated carbon thin films were deposited on sus304 stainless steel substrates by high-power plasma-sputtering with tit... To improve the characteristics of a diamond-like carbon (DLC) film, Ti-containing amorphous hydrogenated carbon thin films were deposited on sus304 stainless steel substrates by high-power plasma-sputtering with titanium metal as the solid plasma source in a mixed ArC2H2 atmosphere. The films were fabricated to obtain a multilayered structure of Ti/TiC/DLC gradient for improving adhesion and reducing residual stress. The effects of substrate bias and target-substrate distance on the films' properties were studied by glow discharge spectroscope, X-ray diffractometer, Raman spectroscope, nanoindenter, and a pin-on-disk tribometer. The results indicate that the films possess superior adhesive strength and toughness. 展开更多
关键词 high-power plasma-sputtering Me-DLC diamond-like carbon
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An efficient design tool based on FEM for evaluating effects of components properties and operating conditions on interaction of tire with rigid road 被引量:7
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作者 Moslem Namjoo Hossein Golbakhshi 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第1期189-195,共7页
It is noted that any variation in operating conditions has a considerable effect on the tire/road interaction. Furthermore,choosing a range of proper values for carcass stiffness is very essential for both tire safety... It is noted that any variation in operating conditions has a considerable effect on the tire/road interaction. Furthermore,choosing a range of proper values for carcass stiffness is very essential for both tire safety and effective driving action. In this work,an elaborated 3D model fully compliant with the geometrical size of radial tire 185/60 R15 is worked up, for evaluating the effects of components properties and working conditions on deformation and stress/strain fields created inside the tire. For the simulation, the tire structure is assumed to be composed of tread, carcass ply, and bead. The mechanical behavior of rubber as main component of tire is described by Mooney-Rivlin material model. The comparison of the obtained results and laboratory tests demonstrates the validity and high accuracy of analysis. 展开更多
关键词 rubber simulation carcass ply stiffness Mooney-Rivlin model
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Experimental Study on the Surface Modification of Ultra Thin DLC Films
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作者 朱守星 朱世根 《Journal of Donghua University(English Edition)》 EI CAS 2005年第3期85-87,共3页
Surface modification of Diamond-like carbon (DLC) films was carried out in order to estimate the reliability of the ultra thin DLC films. The wear resistance, conductivity and mechatronic reliability of the films were... Surface modification of Diamond-like carbon (DLC) films was carried out in order to estimate the reliability of the ultra thin DLC films. The wear resistance, conductivity and mechatronic reliability of the films were studied by contact atomic force microscope (AFM), electric force microscope (EFM) and conductive AFM. The failure mechanism of pits formed and the reason for conductivity changed of DLC films were examined. 展开更多
关键词 Atomic force microscope Diamond-like carbon Surface modification Electromechanical coupling
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2D-ball simulations on stiffness influences for coal bump 被引量:1
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作者 TAN Yun-liang SUN Chun-jiang ZHANG Zhen-yu 《Journal of Coal Science & Engineering(China)》 2009年第2期161-165,共5页
Coal bump is a dynamic process,thus it is necessary to reveal the process validly.2D-ball code is an efficient approach developed by the authors based on the basicDEM rationale proposed by Cundall.Numerical simulation... Coal bump is a dynamic process,thus it is necessary to reveal the process validly.2D-ball code is an efficient approach developed by the authors based on the basicDEM rationale proposed by Cundall.Numerical simulations show that the coal bump experiencesa process of energy accumulation,sudden release of energy and energy decrease.The stiffness of coal particles has a great influence on the coal bump morphosisand particle velocity.Generally,the larger the stiffness of particles,the longer the shootingoff period and the larger the bump velocity.This is in agreement with the results of laboratoryexperiment and in-situ studies.However,the stiffness of particles has an influence onthe quantity value energy and no influence on the releasing energy pattern of the coalbump. 展开更多
关键词 2D-ball code coal bump stiffness of particle simulation
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Dynamic Behaviors of a Moored Floating Structure with Flexible Skirts
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作者 Wen-Kai Weng Duc-Tru Tran Ruey-Syan Shih 《Journal of Energy and Power Engineering》 2016年第1期13-22,共10页
A numerical model was developed by using the dual boundary element method to investigate the dynamic behavior of a moored floating structure with a pair of vertical and flexible skirts attached at its bottom in the li... A numerical model was developed by using the dual boundary element method to investigate the dynamic behavior of a moored floating structure with a pair of vertical and flexible skirts attached at its bottom in the linear wave field. Theoretical conception is based on potential theory with linear external forces. The motions of the structure were assumed to be small and linear. The flexible skirts mounted beneath the structure were assumed uniform flexural rigidity and the thickness of the skirts was negligible. Comparison between the present model and Gesraha's solution was made to verify the results for a moored floating structure with or without rigid skirts. The influence of the skirt rigidity on the moored floating structure, moored lines and waves is investigated in this study. The results show that, the natural frequencies of structure's oscillation, moored force, wave reflection and transmission tend to the region of short-period waves when the flexible rigidity gradually decreases. Positive correlation exists between the aft mooring force and the pitch motion of the floating structure. 展开更多
关键词 Floating structure dual boundary element method response amplitude operators flexible skirts.
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Composite Ni-Nanodiamond Coating Deposited by Electroless Method
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作者 J. Kaleicheva Zdravka Kirilova Karaguiozova +3 位作者 E. Lyubchenko M. Kandeva V. Mishev S. Stavrev 《Journal of Chemistry and Chemical Engineering》 2012年第7期599-603,共5页
The work in this study is focused on investigation of composite nickel coatings. The coatings were deposited on ductile cast iron samples of different composition by electroless method EFTTOM NICKEL with addition of s... The work in this study is focused on investigation of composite nickel coatings. The coatings were deposited on ductile cast iron samples of different composition by electroless method EFTTOM NICKEL with addition of strengthening nanodiamond particles (2-4 nm), The samples were prepared by casting and austempering. The microstructure, microhardness and wear resistance of the coatings were investigated. The thickness of the coatings was also determined (8-10μm). Metallographic analyses, SEM (scanning electron microscopic) investigation, microhardness measurements by knoop method, wear resistance tests were carried out. The coatings with and without heat treatment at 290℃, 6 h were tested. Duplication of microhardness value and improvement of the coating's properties of heat treated coatings were observed. 展开更多
关键词 NANODIAMOND COMPOSITE electroless nickel coating ductile cast iron.
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Rigidity Theorems for Hypersurfaces in Real Space Form
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作者 潮小李 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2001年第3期367-370,共4页
In this paper, a rigidity theorem of hypersurface in real space form will be given. In addition, we obtain rigidity theorems of submanifold in sphere which improve the result of Hou and Xu.
关键词 HYPERSURFACE real space form rigidity.
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