|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | EFFECTS OF SPECIFIED BLANK SIZE ON BODY WRINKLING DURING HYDRODYNAMIC DEEP DRAWING OF TAPERED RECTANGULAR BOX显示文摘In this paper, the forming features of tapered rectangular box during hydrodynamic deep drawing are studied by means of FEM.The effect rules of square blank corner corner amount on body wrinkling are recognized and corresponding methods are discussed. At last, the results of FEM are verified by experi- ment. | L. H. Lang, D. C. Kang, S. H. Zhang, Z. R. Wang, S. J. Yuan, K. B. Nielsen and J. Dancket 1) Department of Materials Engineering, Harbin Institute of Technology, Harbin 150001, China 2) Aalberg University, Denmark | 2000 | Acta Metallurgica Sinica(English Letters)2000，13，2： | 21 |
| 2 | The Instability of the Vortex Sheet along the Shear Line显示文摘The traditional Kelvin-Helmholtz notion of studying the shear instability is not suitable for the case associated with shear line with the strong wind shear in the vortex sheet. Since then. the shear instability becomes the instability of the vortex sheet. If the velocity is induced by the vortex sheet. the inequalities (l - R_r + Ri_d )> 0 and U(v.t)> U(A(t)) become the criterion of the vortex sheet instability. This criterion indicates that 1) the disposition of environment field restrains the disturbance developing along the shear line. 2) There exist multi-scale interactions in the unstable process of the shear line. The calculation of the necessary condition for the instability is also presented in this paper. | 高守亭 | 2000 | Advances in Atmospheric Sciences2000，17，4： | 19 |
| 3 | A LOOP DRAWBEAD RESTRAINING FORCE MODEL IN SHEET METAL DEEP DRAWING PROCESS显示文摘In sheet metal forming, drawbeads are often used to control uneven material flow which may cause defects such as wrinkles, fracture, surface distortion and springback. Appropriate setting and adjusting the drawbead force is one of the most important pa- rameters in sheet metal forming process control. This paper derives the model of loop drawbead restraining force (DBRF) using plastic forming theory, and gives the min imum blankholding force. Experiments are carried out to verify the proposed DBRF model. The good agreement between the calculated values and experiments data justi- fies the proposed loop drawbead restraining force model. | Y.J. Luo, S.P. Li, J.F. Zheng, D.N. He, Y.Q. Zhang, J.L. Cheng and J. Y. Jiang 1)National Mold & Die CAD Engineering Research Center, Shanghai 200030, China 2)Shanghai Volkswagen Automotive Company Ltd.(SVM), Shanghai 201805, China | 2001 | Acta Metallurgica Sinica(English Letters)2001，14，5： | 11 |
| 4 | ON THE TENSILE MECHANICAL PROPERTY OF Si-Mn TRIP STEELS AT HIGH STRAIN RATE显示文摘Tensile mechanical properties of 1.6Si-1.58Mn-0.195C TRIP (transformation-induced plasticity) steels under high strain rate and effects of DP (dual-phase) treatments were studied and compared to the quasi-static tensile behavior. The results show that the increasing of strain rate leads to increasing in their strengths and decreasing in the uniform elongation remarkably. Because the stable retained austenite in TRIP steel can transform to martensite during tensile testing and the material exhibits excellent characteristic of transformation induced plasticity, the plastic deformation behavior is evidently improved and the combination of strength and elongation is superior to that of dual-phase steel, although its strength is smaller than that of DP steel. However, DP treated steel shown lower elongation under dynamic tension in spite of higher strength. A model was proposed to explain the excellent elongation rate of TRIP steel compared with DP steel on the basis of SEM analysis and the strength of the components in microstructure. | X.C. Wei, L. Li, R.Y. Fu and W. ShiSchool of Materials Science and Engineering, Shanghai University, Shanghai 200072, China Manuscript received 18 June 2001 in revised form 7 November 2001 | 2002 | Acta Metallurgica Sinica(English Letters)2002，15，3： | 8 |
| 5 | Surface Defects of Cold-Rolled Ti-IF Steel Sheets due to Non-Metallic Inclusions显示文摘Surface defects of the cold-rolled sheets of Ti-IF steel were studied and analyzed. After analyzing surface defects of cold-rolled sheets, such as shelling defects, holes and sliver defects by SEM/EDS, a variety of inclusions were found. In addition, the distribution of macro-inclusions in slabs was analyzed by MIDAS method. The results show the macroscopic inclusion bands of head slabs and normal slabs are in 1/8 slab thickness regions of both inner arc side and outer arc side. The formation process of the defects in the cold-rolled sheets was simulated with an experimental cold-rolling machine for comparison. The results show that there were three kinds of inclusions underneath the surface defects: Al2O3, SiO2 and particles from slag entrainment, which were the main reason for defect formation during cold rolling. | CUI Heng1, WU Hua-jie1, YUE Feng1, WU Wei-shuang1, WANG Min1, BAO Yan-ping1, CHEN Bin2, JI Chen-xi2 (1. Engineering Research Institute, University of Science and Technology Beijing, Beijing 100083, China 2. Shougang Research Institute of Technology, Beijing 100043, China) | 2011 | Journal of Iron and Steel Research(International)2011，18，S2： | 8 |
| 6 | A one-dimensional heat transfer model of the Antarctic Ice Sheet and modeling of snow temperatures at Dome A, the summit of Antarctic Plateau显示文摘A vertical one-dimensional numerical model for heat transferring within the near-surface snow layer of the Antarctic Ice Sheet was developed based on simplified parameterizations of associated physical processes for the atmosphere, radiation, and snow/ice systems. Using the meteorological data of an automatic weather station (AWS) at Dome A (80°22′S, 70°22′E), we applied the model to simulate the seasonal temperature variation within a depth of 20 m. Comparison of modeled results with observed snow temperatures at 4 measurement depths (0.1, 1, 3, 10 m) shows good agreement and consistent seasonal variations. The model results reveal the vertical temperature structure within the near-surface snow layer and its seasonal variance with more details than those by limited measurements. Analyses on the model outputs of the surface energy fluxes show that: 1) the surface energy balance at Dome A is characterized by the compensation between negative net radiation and the positive sensible fluxes, and 2) the sensible heat is on average transported from the atmosphere to the snow, and has an evident increase in spring. The results are considered well representative for the highest interior Antarctic Plateau. | CHEN BaiLian1,3, ZHANG RenHe2, SUN ShuFen1, BIAN LinGen2, XIAO CunDe4,2 & ZHANG TingJun5 1 Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China 2 Chinese Academy of Meteorological Sciences, Beijing 100081, China 3 Graduate University of Chinese Academy of Sciences, Beijing 100049, China 4 Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China 5 The National Snow and Ice Data Center, University of Colorado, Boulder, CO 80309-0449, USA | 2010 | Science China Earth Sciences2010，53，5： | 7 |
| 7 | pTC-1 observation of ion high-speed flow reversal in the near-Earth plasma sheet during substorm显示文摘Based on measurements of FGM and HIA on board TC-1 at its apogee on Septem-ber 14, 2004, we analyzed the ion high-speed flows in the near-Earth plasma sheet observed during the substorm expansion phase. Strong tailward high-speed flows (Vx ~ -350 km/s) were first seen at about X ~ -13.2 RE in near-Earth magnetotail, one minute later the flows reversed from tailward to earthward. The reversal process occurred quickly after the substorm expansion onset. The near-Earth magnetotail plasma sheet was one of key regions for substorm onset. Our analysis showed that the ion flow reversal from tailward to earthward was likely to be in close relation with the substorm expansion initiation and might play an important role in trigger-ing the substorm expansion onset. | H. RME I. DANDOURAS C. M. CARR | 2008 | Science China(Technological Sciences)2008，51，10： | 6 |
| 8 | EXCEL工作表的保护显示文摘 | 张丹 乔春华 | 2004 | 内蒙古科技与经济2004，，22： | 6 |
| 9 | 基于PI数据库的电厂报表系统的实现显示文摘以火力发电厂厂级监控信息系统中的报表处理为例,阐述了在分布式体系结构的浏览器/服务器(B/S)软件系统中如何实现基于PI数据库的数据提取、数据分析、数据统计,以及自动生成Excel报表的方法。该系统充分利用PI数据库提供给Excel的APl,从而提高了报表的可操作性和灵活性,并已在实际应用中取得了很好的效果。 | 宋人杰 于健 范光伟 | 2005 | 东北电力学院学报2005，25，4： | 6 |
| 10 | Chinese radioglaciological studies on the Antarctic ice sheet: progress and prospects显示文摘Chinese radioglaciological studies on the Antarctic ice sheet(AIS) began in 2004/05 when the 21 st Chinese National Antarctic Research Expedition(CHINARE 21) team arrived at Dome A for the first time and radio echo sounding(RES) was conducted along the inland traverse and in the Dome A region. Subsequently, more field surveys were conducted along the traverse and in the Dome A region using different radar systems targeting different scientific purposes, such as revealing the landscape of the Gamburtsev Subglacial Mountains by detailed grid RES, or locating a deep ice core drilling site by mapping and studying internal structures, bedrock topography and subglacial conditions in the Dome A region. Furthermore, the evolution of the AIS was inferred from the typical mountain glaciation topography beneath Dome A, and the age of the deep ice core at Kunlun Station was estimated through numerical modeling. Recently, the Snow Eagle 601 airplane was acquired and an airborne geophysical system was constructed to survey the AIS in Princess Elizabeth Land during CHINARE 32(2015/16) and CHINARE 33(2016/17) in order to fill the large data gap there. In this paper, we review both the recent progress of Chinese radioglaciological science in Antarctica and future proposed work. | CUI Xiangbin WANG Tiantian SUN Bo TANG Xueyuan GUO Jingxue | 2017 | Advances in Polar Science2017，28，3： | 6 |
| 11 | Mobile bed thickness in skewed asymmetric oscillatory sheet flows显示文摘A new instantaneous mobile bed thickness model is presented for sediment transport in skewed asymmetric oscillatory sheet flows. The proposed model includes a basic bed load part and a suspended load part related to the Shields parameter, and takes into account the effects of mass conservation, phase-lag, and asymmetric boundary layer development, which are important in skewed asymmetric flows but usually absent in classical models. The proposed model is validated by erosion depth and sheet flow layer thickness data in both steady and unsteady flows, and applied to a new instantaneous sediment transport rate formula. With higher accuracy than classical empirical models in steady flows, the new formula can also be used for instantaneous sediment transport rate prediction in skewed asymmetric oscillatory sheet flows. | Xin Chen Yong Li Fujun Wang | 2018 | Acta Mechanica Sinica2018，34，2： | 5 |
| 12 | Statistical research on the motion properties of the magnetotail current sheet:Cluster observations显示文摘The origin of the flapping motion of the earth's magnetotail current sheet is one of the most important problems in the magnetotail dynamics.Using Cluster data,we make a statistical research on the motion properties of the magnetotail current sheet of 2001 and 2003.We calculate the velocities of the magnetotail current sheet using new methods and obtain the distribution of the magnetotail current sheet velocities in the X-Y plane in GSE coordinate system.Our results show that although most of the current sheets were propagating toward the tail flanks and those of the exceptions lay in dusk side,which is consistent with previous studies,the proportions of the current sheet which were propagating toward midnight (where |YGSE|=0) were higher than those in previous studies.Motions of the current sheet in the middle area (|YGSE|<8 Re) of the magnetotail are investigated.Relatively high value of the Z component of the velocity further confirms that the middle area of the magnetotail might be a source region for the motion of the current sheets which were propagating towards the tail flanks.According to our case studies,the way the current sheets propagated toward midnight area differs significantly from that toward dusk and dawn side,from which we infer that there might be two different kinds of current sheet motions originated from different sources.The statistical results of this paper may give some clues for further studies on the origin of the flapping motion of the magnetotail current sheet. | H.REME E.LUCEK | 2010 | Science China(Technological Sciences)2010，53，6： | 5 |
| 13 | Global cooling controls on the chemical weathering as evidenced from the Plio-Pleistocene deposits of the North China Plain显示文摘Major element concentrations were analyzed on the sediments of a 203.6-m core from the North China Plain near Tianjin. The chemical index of alteration (CIA), Al2O3-(CaO+Na2O)-K2O diagram and elemental ratios, such as Al/K and Ti/Na, were used to reveal information of chemical weathering in the source regions since the late Pliocene. Results show that the fluvial materials in the North China Plain were derived from vast regions, which were in the early Na and Ca removal stage and underwent numerous upper-crustal recycling processes. Proxies of chemical weathering show a decreasing trend, in parallel with the global cooling since the late Pliocene, suggesting a strong role of the global cooing in controlling the continental chemical weathering intensity. | YAO ZhengQuan1,2, XIAO GuoQiao1,2 & LIANG MeiYan2,3 1 State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China 2 Graduate University of the Chinese Academy of Sciences, Beijing 100049, China 3 Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China | 2010 | Chinese Science Bulletin2010，55，9： | 4 |
| 14 | A tentative study for the prediction of the CME related geomagnetic storm intensity and its transit time显示文摘Using 80 CME-ICME events during 1997.1―2002.9, based on the eruptive source locations of CMEs and solar magnetic field observation at the photosphere, a current sheet magnetic coordinate (CMC) system is established in order to study the propagation of CME and its geoeffectiveness. In context of this coordinate system, the effect of the eruptive source location and the form of heliospheric current sheet (HCS) at the eruptive time of CME on the geomagnetic storm intensity caused by CME and the CME’s transit time at the Earth is investigated in detail. Our preliminary conclusions are: 1) The geomagnetic disturbances caused by CMEs tend to have the so-called “same side-opposite side effect”, i.e. CMEs erupt from the same side of the HCS as the earth would be more likely to arrive at the earth and the geomagnetic disturbances associated with them tend to be of larger magnitude, while CMEs erupting from the opposite side would arrive at the earth with less probability and the corresponding geomagnetic disturbance magnitudes would be relatively weaker. 2) The angular separation between the earth and the HCS affect the corresponding disturbance intensity. That is, when our earth is located near the HCS, adverse space weather events occur most probably. 3) The erupting location of the CME and its nearby form of HCS will also affect its arrival time at the earth. According to these conclusions, in this context of CMC coordinate we arrive at new prediction method for estimating the geomagnetic storm intensity (Dstmin) caused by CMEs and their transit times. The application of the empirical model for 80 CME-ICME events shows that the relative error of Dst is within 30% for 59% events with Dstmin≤?50 nT, while the averaged absolute error of transit time is lower than 10 h for all events. | ZHAO Xinhua1,2 & FENG Xueshang1,3 1. SIGMA Weather Group, Key Laboratory of Space Weather, Center for Space Science and Applied Re-search, Chinese Academy of Sciences, Beijing 100080, China 2. Graduate School of the Chinese Academy of Sciences, Beijing 100039, China 3. School of Geophysics and Geoinformation Systems, China University of Geosciences, Beijing 100083, China | 2005 | Science China(Technological Sciences)2005，48，6： | 4 |
| 15 | Variation of Stable Isotopes in Surface Snow along a Traverse from Coast to Plateau's interior in East Antarctica and Its Climatic Significance显示文摘The variations of stable water isotopes of surface snow in east Antarctic Ice Sheet, are discussed by a total of 251 samples, which were taken along a 330 km traverse from Zhongshan Station to the outer edge of the Antarctic plateau and from four snow pits excavated along the route. Analyzing results of the samples showed the expected linear relationship between the parameters ?D and ?18O with slope S1 and intercept d1. When the data set was examined using a sliding window with a width of 5 samples, it was found that there were two areas with different ratios of S1 and d1. The boundary between these two areas occurred at an elevation of about 2,000 m, suggesting two different sources of water vapour. Nearly half (47%) of the fresh-snow samples had negative deuterium excess (d=?D? 8?18O) values, but few of the snow pit samples did, suggesting that variations of ? are quickly smoothed by isotopic diffusion in the near-surface firn. Analysis of the phase relationship between ?D and deuterium excess in the snow pit stratigraphies showed that they were mostly in phase from Jan. 1994 to Sept. 1995, but mostly out of phase from Sept. 1995 to Jan. 1997. | Jean Jouzel Michel Stievenard | 2009 | Research in Cold and Arid Regions2009，1，1： | 4 |
| 16 | Feature of flow stress of aluminum sheet used for can during hot compression显示文摘The flow stress feature of aluminum sheet used for pressure can during plastic deformation at elevated temperature was studied by isothermal compression test using Gleeble 1 500 dynamic materials testing machine. The experimental results show that the steady state deformation is remarkable when the material is deformed in the temperature range of 350~500 ℃ at strain rates within the range of 10 -2 ~10.0 s -1 . The material is sensitive to positive strain rate. A hyperbolic sine relationship is found to correlate well the flow stress with the strain rate, and an Arrhenius relationship with the temperature. Semi empirical constitutive equations of the flow stress are derived from all experimental data for tested material during plastic deformation at elevated temperature by polyelement linear regression analysis. [ | 傅高升 钱匡武 陈文哲 康积行 | 2000 | 中国有色金属学会会刊:英文版2000，10，5： | 4 |
| 17 | Analytical and Experimental Studies on Critical Blank-holder Forces in Cylindrical cup deep drawing显示文摘Based on the plastic deformation theory and energy method, the critical blank-holder forces (BHF) of wrinkling and fracture in the cylindrical cup deep-drawing are analyzed. The verify experiments were performed and compared with the theory analysis results. The predictions agree well with the experiment results. Thus, the validated presenttheoretical analysis model may be applied to determinate the suitable BHF. | Lin Zhongqin Sun Chengzhi Chen Guanlong Yu Haiyan | 2004 | 上海交通大学学报2004，38，z2： | 4 |
| 18 | Preparation and properties of high-strength molybdenum alloy sheets doped with Al_2O_3 particles显示文摘The pure molybdenum sheet and the Al_2 O_3-doped molybdenum alloy sheets were prepared by the hydrothermal method and a subsequent powder metallurgy process. The effects of Al_2 O_3 particles addition on the recrystallization temperature, microstructures and properties of the Mo sheets were investigated as the focus. The Al_2 O_3-doped Mo sheets have greater strength than the pure Mo sheet, and the 0.50 wt% Al_2 O_3-doped Mo sheet has the best performance. For the unannealed specimens, the strength increases with the increase in Al_2 O_3 content.Compared with that of pure Mo sheet, the strength of0.50 wt% Al_2 O_3-doped Mo sheet increases by 72%, 54%,73% and 76%, respectively, when annealed at 1000,1100,1200 and 1300 ℃, which is a very obvious reinforcement effect. When lower than 1100 ℃, the elongation of the pure Mo sheet is the best. However, when the annealing temperature is equal to or greater than 1100 ℃,the 0.50 wt% Al_2 O_3-doped Mo sheet obtains the best elongation. Moreover, the Al_2 O_3 addition can greatly improve the recrystallization temperature of molybdenum sheets; for example, the recrystallization temperature of the0.50 wt% Al_2 O_3-doped Mo sheet increases by 200 ℃ at least than that of the pure Mo sheet. Lastly, the strengthening mechanism was discussed. | Yu-Cheng Zhou Yi-Min Gao Shi-Zhong Wei Ya-Jie Hu | 2018 | Rare Metals2018，37，12： | 4 |
| 19 | An analytical symplectic approach to the vibration analysis of orthotropic graphene sheets显示文摘A nonlocal continuum orthotropic plate model is proposed to study the vibration behavior of single-layer graphene sheets(SLGSs) using an analytical symplectic approach. A Hamiltonian system is established by introducing a total unknown vector consisting of the displacement amplitude, rotation angle, shear force, and bending moment.The high-order governing differential equation of the vibration of SLGSs is transformed into a set of ordinary differential equations in symplectic space. Exact solutions for free vibration are obtianed by the method of separation of variables without any trial shape functions and can be expanded in series of symplectic eigenfunctions. Analytical frequency equations are derived for all six possible boundary conditions. Vibration modes are expressed in terms of the symplectic eigenfunctions. In the numerical examples, comparison is presented to verify the accuracy of the proposed method. Comprehensive numerical examples for graphene sheets with Levy-type boundary conditions are given. A parametric study of the natural frequency is also included. | Xinsheng Xu Dalun Rong C.W.Lim Changyu Yang Zhenhuan Zhou | 2017 | Acta Mechanica Sinica2017，33，5： | 4 |
| 20 | Studies of solar flares and CMEs related to the space solar missions in the future显示文摘Solar eruptions and the related processes involve magnetic fields and plasma flows of various scales in both time and space. These processes include the convective motions of the mass and magnetic field in the photosphere, evolutions of magnetic fields in both the chromosphere and the corona prior to and during the disruption of magnetic fields in response to the photospheric motions. These evolutions constitute a whole process of transporting the magnetic energy and the helicity from the photosphere to the corona, and then to interplanetary space. The present work, on the basis of a solar eruption model, discusses these processes, and the related questions, unanswerable at present, but could be the scientific objectives of the space solar missions in the future. | LIN Jun1,21 National Astronomical Observatories/Yunnan Astronomical Observatory, Chinese Academy of Sciences, Kunming 650011, China 2 Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA | 2009 | Science China(Physics,Mechanics & Astronomy)2009，52，11： | 3 |
您所在的机构暂未开通此部分的功能，请联系管理员