检索结果-南通市图书馆

Relationship Between Activity Interaction Parameters in Fe-C System and Temperature

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel research International 2009年第2期16卷 11-16页

作者： CHEN Er-bao LIU Mao-liu WANG Shi-jun School of Metallurgy and Materials Anhui University of Technology Ma'anshan 243002 Anhui China first factory of Steelmaking and Rolling Maranshan Iron and Steel Co Ltd Maranshan 243000 Anhui China

Carbon solubility in Fe-Mn melts （XFe =0. 102 3-0. 789 9, XMn =0. 055 1-0. 638 0） was measured experimentally at various temperatures. Using Gibbs-Duhem equation, in combination with the experimental results in this work, quoting experimental data reported in references, and by strict thermodynamic derivation and calculation, the relation equations between the activity interaction parameters in Fe-C system and temperature were obtained. The calculation equation of lnyFe. in Fe-C system was also obtained. The calculated results show that these relation equations can be used to calculate the activity coefficients of carbon and iron in Fe-C system and can satisfy the necessary condition to satisfy Gibbs-Duhem equation and the necessary condition to satisfy the stability condition of system at high carbon content. The calculation formula for lnTc in Fe-Mn-C system was also obtained.

关键词： Fe-C system activity interaction parameter activity coefficient carbon

Combined adjustment project of national astronomical geodetic networks and 2000' national GPS control network

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2005年第5期15卷 435-441页

作者： YANG Yuanxi1*, ZHA Ming2, SONG Lijie3, WEI Ziqing1, WANG Zhouping2, OUYANG Guichong2, XU Bilin2, WU Xiaoping3 and WANG Junqin4(1. Xi'an research institute of Surveying and Mapping, Xi'an 710054, china 2. Xi'an Informational and Technical Center of Surveying and Mapping, Xi'an 710054, china 3. Zhengzhou institute of Surveying and Mapping, Zhengzhou 450052, china 4. The first Surveying Team of Tianjin, Tianjin 300140, china) Xi'an res. inst. of Surveying and Mapping Xi'an 710054 China Xi'an Info. and Technical Ctr. of Surveying and Mapping Xi'an 710054 China Zhengzhou inst. of Surveying and Mapping Zhengzhou 450052 China first Surveying Team of Tianjin Tianjin 300140 China

The combined adjustment project of the nationwide astronomical geodetic networks and 2000' national GPS control network involve 48519 terrestrial observational stations and 2666 GPS observational stations. In the terrestrial network, 25107 stations are height fixed and 23412 stations are in three dimensions. 440793 terrestrial observations and 183668 unknowns are involved in the adjustment. The three-dimensional observational models for the adjustment have been established. The crustal deformation influences and corrections are researched. Fast methods of solving partitioned adjustment for super large-scale geodetic network have been studied. The standard deviations of three-dimensional coordinates for all stations are evaluated. As a result of the combined adjustment, a unified national geodetic network with nearly 50000 stations is established, the high accurate three-dimensional geocentric coordinates are obtained. The standard deviation for geoid is averagely 0.2 m, for vertical deflection is about 1.5″, for the horizontal position is about 0.12 m, for the geodetic height is about 0.14 m, and for the three-dimensional position is averagely 0.3 m.

关键词： astronomical geodetic network GPS network combined adjustment datum geocentric coordinates.

FAILURE ANALYSIS OF PEELING PROCESS FOR TITANIUM ANODES COATINGS

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 1995年第4期5卷 104-107页

作者： Tang, DA Chen, SR Lin, XA Cui, X Yan, Q FUZHOU UNIV INST MAT RESFUZHOU 350002PEOPLES R CHINA FUJIAN res inst MET FUZHOU 350011PEOPLES R CHINA

ＦＡＩＬＵＲＥＡＮＡＬＹＳＩＳＯＦＰＥＥＬＩＮＧＰＲＯＣＥＳＳＦＯＲＴＩＴＡＮＩＵＭＡＮＯＤＥＳＣＯＡＴＩＮＧＳＴａｎｇＤｉａｎ；ＣｈｅｎＳｈｉｒｅｎ（ＩｎｓｔｉｔｕｔｅｆｏｒＭａｔｅｒｉａｌｓＲｅｓｅａｒｃｈ，Ｆｕ... 详细信息

ＦＡＩＬＵＲＥＡＮＡＬＹＳＩＳＯＦＰＥＥＬＩＮＧＰＲＯＣＥＳＳＦＯＲＴＩＴＡＮＩＵＭＡＮＯＤＥＳＣＯＡＴＩＮＧＳＴａｎｇＤｉａｎ；ＣｈｅｎＳｈｉｒｅｎ（ＩｎｓｔｉｔｕｔｅｆｏｒＭａｔｅｒｉａｌｓＲｅｓｅａｒｃｈ，ＦｕｚｈｏｕＵｎｉｖｅｒｓｉｔｙ，Ｆｕ...

关键词： titanium anodes failure analysis coating peeling

Design of flying vehicle control system by signal to noise ratio

在线全文

学校读者我要写书评

暂无评论

Journal of Harbin institute of Technology(New Series) 2001年第1期8卷 63-68页

作者：孙龙大 res. inst. of china Xi'an 710065 China

Presents the new concept of ″Desired to be small″ based on the basic function of vehicle flight control system for an optimal design of flying vehicle control system, and the definition of S/N ratio and calculation formula for ″Desired to be small″ dynamic characteristics, and the S/N ratio method established for design of velicle flight control systems, by which, an orthogrnal table is used to arrange test schemes, and error facters are used to simulate various interferences, and the use of S/N ratio as a design criterion to synthesise the design of dynamic and static characteristics for definition of an optimal scheme, the application of S/N ratio method to the design of a type of vehicle control system and the single run success abtained in design of control system, technical evaluation test and design finalization flight test.

关键词： S/N ratio method control system dynamic characteristics static characteristics parameter design

Mechanism of Burn resistance of Alloy Ti40

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2001年第6期17卷 677-678页

作者： Yongqing ZHAO, Lian ZHOU,Kanging ZHU,Henglei QU and Huan WU Northwest institute for Nonferrous Metal research, Xi’an 710016, china [Manuscript received June 5, 2000] inst. for Nonferrous Metal res. Xi'an 710016 China

The Ti fire found in high performance engines promotes the development of burn resistant Ti alloys. The burn resistant mechanism of Ti40 alloy is investigated. Ti40 alloy reveals good burn resistance. Its interfacial products between burning products and the matrix are tenacious, which retard the diffusion of oxygen into the matrix. Two burn resistant mechanisms, that is, fast scatter dispersion of heat and suppression of oxygen diffusion, are proposed.

关键词： Ti Mechanism of Burn resistance of Alloy Ti40

Diffusion mechanism of dezincification in double phase brass exposed to seawater

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 1999年第3期9卷 572-577页

作者： Liu Zengcai(刘增才) Lin Leyun(林乐耘) Liu Shaofeng(刘少峰) Zhao Yuehong(赵月红) Gen res inst NonFerrous Met Beijing 100088 Peoples R China

Zinc diffusion kinetics of double phase brass as they were corroded in seawater was investigated by means of metallography microscope and mathematics regression analysis. The results showed that, the dezincification corrosion of β phase continuous HMn58 2 brass is characterized by β phase volume diffusion, while that of α phase continuous HSn62 1 brass is controlled by α phase grain boundary diffusion. Apparent diffusion coefficients of zinc in both types alloys were calculated out by founding diffusion equation and boundary conditions. It was found that the value of theoretical calculation is close to that of experimentally measured, and it confirmed that Sn element inhibits dezincification of brass. The relativity between the dezincification depth and corrosion rate of different double phase brasses immersed in seawater was revealed. : Zinc diffusion kinetics of double phase brass as they were corroded in seawater was investigated by means of metallography microscope and mathematics regression analysis. The results showed that, the dezincification corrosion of β phase continuous HMn58 2 brass is characterized by β phase volume diffusion, while that of α phase continuous HSn62 1 brass is controlled by α phase grain boundary diffusion. Apparent diffusion coefficients of zinc in both types alloys were calculated out by founding diffusion equation and boundary conditions. It was found that the value of theoretical calculation is close to that of experimentally measured, and it confirmed that Sn element inhibits dezincification of brass. The relativity between the dezincification depth and corrosion rate of different double phase brasses immersed in seawater was revealed.

关键词： seawater corrosion brass dezincification boundary diffusion

A Novel Telecommunication System:HAPS

在线全文

学校读者我要写书评

暂无评论

china Communications 2007年第2期4卷 79-85页

作者： Sun Zhenqiang Zhu Xuetian china Telecom Beijing res inst Beijing Peoples R China

This paper has identified the main research and development programs in HAPS and their applications across the *** spectrum and licensing issues are presented according to the latest ITU *** make HAPS play a vital rol... 详细信息

关键词： HAPS 3G wireless access satellite airship

The System Performance for TD-LTE with Precoded MIMO

在线全文

学校读者我要写书评

暂无评论

china Communications 2008年第3期5卷 90-94,10页

作者： Zhang Yong Jiang Dajie Shen Xiaodong Han Lu Liu Guangyi Cui Cunfeng Huang Yuhong res inst china Mobile Mobile AL USA

This paper introduces the rank adaptive precoded MIMO in TD-LTE downlink system.

关键词： The System Performance for TD-LTE with Precoded MIMO code LTE TD eNodeB

STUDIES ON GREY MODEL DYNAMIC PREDICTION TO CAVITATION DAMAGE OF TURBINES

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2003年第5期15卷 29-34页

作者： Wu Fu sheng, Tong Zhong shan, Li Yun hui Nanjing Hydraulic research institute, Nanjing 210029, china Nanjing Hydraulic res. inst. Nanjing 210029 China

In thus paper, cavitation damage of turbines is firstly analyzed andpredicated from the view point of system engineering by use of the grey system theory. A detaileddescription of modeling, dynamic prediction and accuracy test for the grey system of turbines wasgiven. Two special cases for grey dynamic prediction as well as its accuracy test were *** results fall into the grade I, the accuracy is satisfactory and its prediction requirements canbe met well. It shows that the grey system theory can be employed to predict the cavitation damageof turbines, and it can provide a scientific basis for timely investigation and maintenance ofturbines.

关键词： turbine cavitation damage grey prediction