从宏观理论上论图书馆的采访工作

随着社会经济的飞速发展和因特网的出现,采访工作遇到了许多新的问题和矛盾,旧的方法已经不能解决新形势下采访工作面临的问题.从以往图书馆采访工作模式宏观分析着手,探询了图书馆的面临的现实状况,阐述了及时采取对策,促进图书馆事业的蓬勃发展.     

受钢工况钢包壁应力场的模拟与分析

ANSYS程序是进行热和结构分析的好工具,它在钢包上的应用非常广泛。以钢包二维截面为研究对象,分别讨论受钢工况下耐火材料物性参数和不同的工作层厚度对包壁应力场分布的影响,从而为钢包设计提供一些依据。     

树立精品意识,努力创办一流期刊--在《中国工程咨询》杂志2005年度通讯员工作会议暨创刊五周年纪念会上的讲话

有机会参加〈中国工程咨询〉杂志2005年度通讯员工作会议暨创刊五周年纪念会,我感到非常高兴.首先,对这次会议的召开表示热烈的祝贺.同时,作为国家发改委主管媒体工作的单位的代表,对大家多年来为办好〈中国工程咨询〉杂志所做的工作,以及对国家发改委主管的其他媒体所给予的关心和支持表示衷心的感谢.……     

Anticoagulation property and security of artificial heart valve material

Cardiovascular disease becomes one of the primary diseases that cause human death.Artificial heart valve’s replacement is the only way to save lives of the patients whoseheart valve is badly pathologically changed by rheumatic heart disease, retrogressiveheart disease, and bacterium caused endocarditis disease. The clinically used artificialheart valves are classified into biomedical heart valve and mechanical heart valve. Thebiocompatibility and anti-thrombus property of the biomedical heart…     

Dispersive bubble wall——a new method of flow control in tundish

Tundish is the last refractory vessel in the steelmaking process. The fluid flow phenomena in tundish have a strong influence on the separation of non-metallic inclusions. The dispersive bubble wall （DBW） is a new method in tundish metallurgy. A water model of a multi-strand tundish has been set up based on the Froude number and Reynold number similarity criteria. The effect of DBW＋weir on the flow pattern has been studied. The results show that this new structure of DBW＋weir is beneficial not only to uniform the temperature among different submerge entry nozzles but also to separate non-metallic inclusions from liquid steel. The DBW can capture the particles of non-metallic inclusions and make them float up to the surface.     

Fractal character of lenticles and its influence on sediment state in tailings dam

1INTRODUCTION Undertheinfluenceofthevariousfactors,suchasaseriesoftailingswithdifferentparticle sdiametersandtailingsdisposal,theprocessoftail ingssedimentisverycomplicated.Thearsenicdis posalpracticeofthemetallurgicalindustryandthesedimentofthedisposedarseniccompoundswerereviewedbyRiverosetal[1].Wind wave induced suspensionofminetailingsindisposalpondwasstudiedbyLawrenceetal[2]withimplicitfinitedifference.Samadetal[3]usedlinearwavetheoryandcountercurrentflowprofilestoobtainthetotalbotto…     

Yielding of Microstructured Geomaterial by Distinct Element Method Analysis

The purpose of this paper is to present macro- and micro-study on the yielding of microstructured geomaterials by numerical experiments. This target is achieved by carrying out 63 one-dimensional and biaxial compressions tests on an idealized bonded geomaterial with an extension of distinct element method, into which bond contact models proposed were implemented. Numerical results indicate that: (a) preconsolidated pressure appears to attribute to bond and looseness in the geomaterials, and an increase in void ratio leads to a decrease in yielding stress in one-dimensional tests; (b) an increase in bonding strength at interparticle contacts results in an increase in yielding stress and cohesion, and an internal friction angle that is smaller than the critical state value; (c) the observed first-yielding (initiation of bond breakage) is stress path dependent, and gross-yield (defined with respect to volumetric strain) of microstructured geomaterials is evidently related to bond breakage.     

电弧冶炼炉的随机干扰辨识与校正

详细分析了电弧冶炼炉控制系统中的几种主要随机干扰,进行了模糊聚类辨识,并建立模糊关系矩阵,在此基础上进行了电弧冶炼炉的模糊控制设计和自校正设计。     

Cold Modelling of Slag Splashing in LD Furnace by Oxygen Lance with Twisted Nozzle Tip

The effects of a conventional lance tip with 4 normal nozzles and a lance tip with 4 twisted nozzles on slag splashing were investigated. A cold model for LD converters, Jiuquan Iron & Steel Co., was established and the amount of slag splashed onto the model walls was measured in the cold modelling experiments. The results from the experiments show that at low top gas flow rate the amount of slag splashing for the tip with twisted nozzles is less than that for the conventional tip, whereas at high top gas flow rate the amount of slag splashing for the nozzle twisted lance is greater than that for the conventional lance. For the nozzle twisted lance tip, slag splashing rates increase with increase in slag amount, lance height and top gas flow rate and the maximum amount of slag splashing for the tip with twisted nozzles can be obtained under the process parameters of 47.6 Nm³/h gas flow rate, 12% slag amount and 247 mm lance height. More slag droplets can be directed onto the cone with a nozzle twisted lance tip than with a normal lance tip at high top gas flow rate.     

田湾核电站2004年(运行前)的环境监测

田湾核电站环境监测系统于2003年底前建成,为了检验田湾核电站环境监测的仪器设备、规程文件、质控措施和人员的技术水平是否满足运行时的要求,扩大和改善运行前的环境本底数据,并通过实践的经验反馈发现存在的问题,提出改进方案和措施,田湾核电站在2004年对核电站周围进行了（运行前）的环境监测.本文主要介绍2004年环境监测的方案、质量保证和主要监测结果及其与2000年4月～2002年3月二年的本底调查结果的比较.2004年监测结果表明,除海水中137Cs活度浓度与本底调查有明显差异外,其余监测结果与本底调查结果基本吻合.