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便携式液相色谱系统及其应用

农业工程 2012年第5期2卷 43-47页

作者： (beijing ChuangXinTongHeng Science & technology co.,ltd.,beijing 100085,china) 北京创新通恒科技有限公司

便携式液相色谱系统是一种定位于食品安全和环境保护的现场快速检测设备。该仪器介绍了推出的背景、必要性及优势,并应用该系统对氨基甲酸酯类农药残留、三聚氰胺以及苏丹红进行检测,结果准确可靠,重现性好。

关键词：便携式高效液相色谱食品安全现场检测

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基于企业流程的需求形式化验证技术

计算机工程与应用 2003年第28期39卷 216-220页

作者：郑跃斌北京华夏新达软件股份有限公司北京100085

需求验证是为了确保需求规格说明具有良好特性(完整性、一致性、无二义性)而对需求规格说明进行的一种审查活动。目前广泛使用的需求验证技术存在着两个问题:难以处理大型、复杂的需求文档;审查过程需要相当长的时间。该文所研究的基于... 详细信息

需求验证是为了确保需求规格说明具有良好特性(完整性、一致性、无二义性)而对需求规格说明进行的一种审查活动。目前广泛使用的需求验证技术存在着两个问题:难以处理大型、复杂的需求文档;审查过程需要相当长的时间。该文所研究的基于企业流程的需求形式化验证技术,通过对需求文档中企业流程各活动之间的逻辑关系进行验证,从而发现其中的不一致性和二义性。

关键词：企业流程需求验证软件工程

THE EFFECTS OF SPUTTERING POWER ON STRUCTURE AND ELECTRICAL PROPERTIES OF Cu FILMS

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Acta Metallurgica Sinica(English Letters) 2002年第2期15卷 215-220页

作者： F.P. Wang. P. Wu, L.Q. Pan, Y. Tian and H. Qiu Department of Physics, School of Applied Sciences, University of Science and technology beijing, beijing 100083, china beijing Keda-Tianyu Microelectronic Material technology Development co. ltd., beijing 100 beijing Keda-Tianyu Microelectronic Material technology Development co. ltd. Beijing 100083China

Cu films with thickness of about 500nm were deposited on glass substrateswithout heating by DC magnetron sputtering in pure Ar gas of 1.0Pa. The sputtering powers weremaintained at 390V X 0.27A, 430V X 0.70A and 450V X l.04A, and the co.responding deposition rates ofCu film reached 35nm/min, l04nm/min and 167nm/min. X-ray diffraction, scanning electron microsco.yand atomic force microsco.y were used to observe the structural characteristics of the films. Theresistance of the films was measured using four-point probe technique. The amount of larger grainsincreases and the resistivity of the films decreases evidently with an increase in sputtering *** is co.sidered that the increase in deposition rate with sputtering power mainly weakens theinfluence of residual gas atoms on the growing film, and increases substrate and gas temperatures,resulting in the increase in grain size and the decrease in resistivity of the Cu film.

关键词： Cu film DC magnetron sputtering sputtering power structure resistivity

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基于协同平台构建施工企业项目管理系统

施工技术 2003年第12期32卷 1-3页

作者：王建北京梦龙科技(集团)有限公司北京100043

项目管理系统是以网络计划技术为核心,以协同工作平台为基础平台形成的。本文介绍了网络计划技术及协同工作平台的特性及其在项目管理中的应用。

关键词：项目管理施工企业网络计划工作平台

Model test investigation on an innovative lifting system for deepwater riser installation

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Petroleum Science 2010年第4期7卷 547-554页

作者： Mao Dongfeng Duan Menglan Wang Yi He Ning Chen Bangmin Zhang Yingjie School of Mechanical Engineering Yangtze University Jinzhou Hubei 434023 China Offshore Oil/Gas Research Center China University of Petroleum Beijing 102249 China Department of Naval Architecture ＆ Ocean Engineering Dalian University of Technology Dalian Liaoning 116023 China Offshore Oil Engineering co. Ltd. Tanggu Tianjin 300452 China

An S-lay crane barge,named CNOOC 201,has been built for pipe laying in deepwater oil/gas fields in the South china *** is due to be co.missioned by the end of the year 2010.A special lifting system is developed to meet the challenge that installing deepwater risers from an S-lay barge is difficult and has not been *** purpose of this paper was to investigate the model test on such an innovative system,which has to be done before field *** applying the similarity theory,the movement of the S-lay barge is simulated through a six degrees-of-freedom motion platform,and a truncated model riser is utilized for the model *** displacement and force boundary co.ditions at the truncated position of the riser are obtained from the catenary governing equation and beco.e realized by a slideway cart and a loading system designed to co.trol the co.figuration of the model riser,which presents a similar co.figuration to a real riser in *** test results are in very good agreement with theoretical calculations,showing that the active truncated test is applicable for co.trolling the co.figuration of the deepwater riser in model testing investigation.

关键词： Deepwater riser lifting system model test six degrees-of-freedom motion platform active truncation

Motion behavior of particles in air-solid magnetically stabilized fluidized beds for separation

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International Journal of Mining Science and technology 2012年第5期22卷 725-729页

作者： Song Shulei a,,Zhao Yuemin a,Luo Zhenfu a,Tang Ligang b a School of Chemical Engineering and technology,china University of Mining & technology,Xuzhou 221116,china b co.l Mining and Designing Department,Tiandi Science & technology co.pany co.ltd.,beijing 100013,china School of Chemical Engineering and technology China University of Mining & Technology Xuzhou 221116 China co.l Mining and Designing Department Tiandi Science & Technology Company Co. Ltd. Beijing 100013 China

In order to study the settling mechanism of particles in an air-solid magnetically stabilized fluidized bed(MSFB) for separation,we carried out free settling and quasi-zero settling tests on the tracing *** results show that the main resistance forces as the tracing particles settled in an air-solid MSFB were motion resistance force and yield *** motion resistance and yield forces greatly hindered the free settling of the particles by greatly decreasing the acceleration for settling process of the *** acceleration decreased from 3022.62 cm/s 2 to zero in 0.1 s,and in the end,the particles stopped in the air-solid *** yield force on particles increased with increasing the magnetic field intensity,resulting in decrease of the quasi-zero settling ***,the yield force on particles decreased with increasing the fluidized air velocity,leading to increase of the quasi-zero settling *** the structure and operating parameters of the air-solid MSFB were set up,the yield stress on particles stopped in an air-solid MSFB was a function of diameter and density of *** settling displacements of equal diameter particles increased with increasing their densities,and the settling displacements of equal density particles increased with increasing their diameters.

关键词：磁稳定流化床颗粒沉降运动行为分离 MSFB 沉降位移示踪粒子沉降试验

Investigation on Variation of Inclusions and Total Oxygen in IF Steel After RH Deoxidization

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Journal of Iron and Steel Research(International) 2011年第S2期18卷 347-351页

作者： SHU Hong-fu1,2, LIU Liu1, LIU Xue-hua2, ZHANG Xiao-feng2 (1.Central Iron and Steel Research Institute, beijing 100081, china 2. technology Centre of Maanshan Iron and Steel co.ltd. Maanshan 243000, Anhui, china) Cent Iron & Steel Res Inst Beijing 100081 Peoples R China Maanshan Iron & Steel co.ltd Ctr Technol Maanshan 243000 Anhui Peoples R China

The variational regulation of inclusions and total oxygen in the IF Molten Steel during the RH refining process after deoxidization was studied. The results show that the relationship between total oxygen co.tent and time is in acco.d with the following equation, T.O=271.25e-1.53t+23.49, R2=*** inclusion analysis investigation during RH pure circulation process indicates that the main inclusion of the IF molten steel after 2 minutes from the beginning of deoxidization is cluster inclusions of pure Al2O3 system. After 6 minutes from the aluminum deoxidization, the quantity of inclusion decreases and the inclusion style changes into block inclusions of Al2O3 system with the size of 5μm. In the other hand, some inclusions are of Al2O3-MgO. co.plex inclusions of Al2O3-TiOx with the size of below 5μm, and the single particle or cluster co.plex inclusions with the typical square shape of Al2O3-TiN system are found after 3 minutes from titanium-ferrous alloy added. Then, the co.tent of titanium of co.plex inclusions of Al2O3-TiOx decreases and the aluminum co.tent rises along with the RH pure circulation time process. That means the inclusions of Al2O3-TiOx is not steady, and it trends to transfer into Al2O3.

关键词： IF steel inclusion RH refining

A statistical model for porous structure of rocks

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Science china(Technological Sciences) 2008年第11期51卷 2040-2058页

作者： JU Yang1,2, YANG YongMing1, SONG ZhenDuo3 & XU WenJing4 1 State Key Laboratory of co.l Resources and Safe Mining, china University of Mining & technology, beijing 100083, china 2 Department of Mechanical and Manufacturing Engineering, The University of Calgary, 2500 University Drive NW Calgary, AB T2N 1N4, Canada 3 china National co.l Mining Equipment co. ltd. beijing 100011, china 4 Department of Materials and Metallurgy, The University of Utah, Salt Lake City, Utah 84112, USA State Key Laboratory of co.l Resources and Safe Mining China University of Mining & Technology Beijing China Department of Mechanical and Manufacturing Engineering The University of Calgary Calgary Canada china National co.l Mining Equipment co. ltd Beijing China Department of Materials and Metallurgy The University of Utah Utah USA

The geometric features and the distribution properties of pores in rocks were in- vestigated by means of CT scanning tests of sandstones. The centroidal co.rdi- nates of pores, the statistic characterristics of pore distance, quantity, size and their probability density functions were formulated in this paper. The Monte Carlo method and the random number generating algorithm were employed to generate two series of random numbers with the desired statistic characteristics and prob- ability density functions upon which the random distribution of pore position, dis- tance and quantity were determined. A three-dimensional porous structural model of sandstone was co.structed based on the FLAC3D program and the information of the pore position and distribution that the series of random numbers defined. On the basis of modelling, the Brazil split tests of rock discs were carried out to ex- amine the stress distribution, the pattern of element failure and the inosculation of failed elements. The simulation indicated that the proposed model was co.sistent with the realistic porous structure of rock in terms of their statistic properties of pores and geometric similarity. The built-up model disclosed the influence of pores on the stress distribution, failure mode of material elements and the inosculation of failed elements.

关键词： porous structure statistical model random numbers reco.struction rocks

Effect of ball milling process on the microstructure of titanium-nanohydroxyapatite co.posite powder

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Rare Metals 2007年第2期26卷 118-123页

作者： PANG Pengsha LI Wei LIU Ying Department of Materials Science and Engineering Jinan University Guangzhou 510632 China GRIPM Advanced Materials co. ltd General Research Institute for Nonferrous Metals Beijing 100088 China

Titaninm-nanohydroxyapatite （Ti-nHA） co.posite powders, co.posed of titanium with 10 vol.% and 20 vol.% of nano-hydroxyapatite, were milled in a planetary ball mill using alco.ol media to avoid excessive heat. XRD and SEM were performed for characterization of the microstructure, and the homogeneity of Ti/HA nanoco.posite powder was evaluated by EPMA with prolonged ball milling time. The results show that under the co.dition of wet milling, the grain size of Ti-nHA co.posite powders is decreased with the increase in ball milling time and the amount of the addition of nHA. While for milling of 30 h, the nanoco.posite powder with free structure, which co.sists of the nano-hydroxyapatite （nHA） particles and titanium （Ti） phase, is obtained. Three stages of milling can be observed from the dement mapping of Ti, Ca, and P by EPMA; meanwhile, it is found that the nHA would be more homogenously distributed after milling for 30 h.

关键词： co.posite materials nanoco.posites mechanical milling titanium nanohydroxyapatite