润磨工艺处理钒钛磁铁矿的实践

本文为使用润磨工艺处理攀枝花钒钛磁铁矿条件试验、润磨料润湿程度和润磨造球试验,找到了润磨机参数间相互关系及其变化趋势,最后获得了高质量的生球强度,为今后研制大型润磨机处理攀枝花矿提供了试验数据和操作依据。     

重钢配加精选硫酸渣润磨生产实验研究

通过本实验，对在润磨生产中配加精选硫酸渣进行了系统的研究，并探讨了全润磨、半润磨、不润磨三种不同生产方式对生产质量的影响及其在重钢的实践意义。     

新型润磨给料机的应用

一种新型的可移动式皮带给料机已成功应用于润磨机供料。该给料机不仅简化了润磨机供料流程 ,减少了设备投资 ,而且提高了设备作业率 ,便于润磨机的操作和维护 ,完全可以替代目前国内普遍应用的皮带 螺旋给料机供料系统     

润磨机的安装与投用实践

介绍了水冶钢铁公司球团矿配料系统中润磨机的安装情况,对润磨机的作用、组成及工作原理作了简单介绍;在设备试运行期间,密切关注各项技术指标,及早发现设备试运行中存在的隐患,保证了润磨机负荷试车一次成功.     

润磨强化镜铁精粉烧结特性的研究

巴西镜铁精粉难制粒反应性差,通过润磨单一镜铁矿或其与石灰石的混合料可改善其表面性质和高温反应性能.测定润磨预处理前后巴西镜铁矿的润湿热、粒度组成及变形温度等指标,揭示其作用机理.并通过烧结杯试验,考察润磨预处理强化烧结的效果.研究结果表明,润磨改善了巴西镜铁矿的润湿热,表面亲水性得到改善;降低了变形温度,提高了巴西镜铁矿的高温反应性能.巴西镜铁矿预处理后,烧结矿产量和质量得到大幅度改善,成品率增加了3.7%,转鼓强度提高了3.33%,固体燃耗降低了约4 kg/t ,利用系数提高22.4%,烧结矿质量完全能满足高炉生产的需要.     

优化大冶竖炉球团焙烧工艺参数的试验研究

为了探索改善球团矿原料质量的途径,用润磨处理和未润磨处理精矿作原料的球团矿,按大冶竖炉球团矿生产的工艺条件在实验室进行了预热、焙烧等项目的试验。试验表明,在同样的预热、焙烧的工艺参数下,用润磨原料生产的球团矿,其抗压强度高于未润磨原料生产的球团矿;如按球团矿抗压强度达到3000N／个为基准,润磨原料比未润磨原料需要较少的预热时间、焙烧时间和较低的预热温度、焙烧温度。采用润磨技术处理精矿是改进竖炉球团矿生产的一项有效措施。     

水冶竖炉球团配混料系统改造及达产实践

介绍了安钢水铁对现有竖炉球团配混料系统进行工艺升级,新上了一套配料、烘干、润磨系统。该系统建成投产时,烘干与润磨部分存在一定问题,后经过不断的设备改进、工艺参数的调整,烘干与润磨效果达到了设计要求,同时球团矿产质量有了大幅度的提高。     

马钢竖炉球团润磨工艺优化试验研究

为了优化马钢竖炉球团润磨工艺参数,研究了润磨参数对球团过程的影响.试验结果表明,在马钢条件下,混合料适宜的润磨水分、润磨时间分别在5%～6%、10～12min,适宜的润磨比例在70%水平,适宜的预热、焙烧时间在15～18min;适宜的预热、焙烧温度分别在900℃～950℃、1200℃～1250℃.试验还表明,生球水分低于9.5%时,其爆裂温度均高于600℃.     

原料润磨对球团氧化活化能的影响

本文通过阿仑尼乌斯公式对磁铁矿原料润磨前后球团氧化反应的活化能进行了研究 ,研究表明 :原料不润磨 ,球团氧化反应活化能为 3 3 96kJ/mol;原料经润磨后 ,球团氧化反应活化能为 3 1 68kJ/mol。这说明润磨降低了球团氧化反应的活化能     

马钢球团润磨工艺试验研究

为了优化马钢球团混合料润磨工艺参数，研究了不同润磨参数对球团过程的影响。试验结果表明，在马钢条件下，混合料适宜的润磨水分、润磨时间分别为5％～6％、10-12min，适宜的润磨比例在70％水平，适宜的预热、焙烧时间在15～18min，适宜的预热、焙烧温度分别为900-950、1200～1250℃；试验还表明，生球水分低于9．5％时，其爆裂温度均高于600℃。     

曼型气柜支柱的安装方法

通过对曼型气柜关键部位之一的基柱的安装和找正过程的分析，表明基柱安装前对基础进行预处理、安装时测量跟踪找正、安装后定位加固，是保证基柱安装精度的三个重要步骤。     

矿产资源定价方法的实证研究

文中分析了资源－环境－经济一体化核算的研究现状及存在的问题,界定了矿产资源核算的内涵及其对象,论述了矿产资源定价的理论基础,探讨了矿产资源的各种定价方法及其优缺点,适用范围,建立相应的估价模型,并进行了实证分析,这项研究对我国的资源－－环境－经济一体化核算的理论研究与实践进展具有重要的理论意义和现实意义。     

企业信息管理系统的建设道路

本文论述了企业计算机信息管理系统建设的必要性，所面临的问题，大中型企业ＭＩＳ规划思想，ＭＩＳ系统建设实施步骤，并根据国有企业现状和特点，重点分析了其在建设ＭＩＳ系统中可供选择方式，可能遇到的问题及其解决方法等。     

Experimental studies of the effects of atmospheric pollutants]

Experimental studies in man are an indispensable complement to epidemiological studies and experimental studies on animals. They aim at understanding the mechanisms of action of the main pollutants and at knowing their thresholds of triggering of the acute effects on the respiratory system. The studies made in man involve controlled exposure to different atmospheric pollutants, with measurement of the functional respiratory repercussions, studies of modification of the cells in broncho-alveolar lavage, as well as experimental protocols that combine inhalation of allergen and exposure to atmospheric pollutants by allergic subjects. The main results that are available are reported to distinguish those from normal subjects and those who are allergic. More recent protocols are based on exposure to concentrations that are close to atmospheric concentrations or those that are met in work places. The main data in the literature are reported in this journal and concern SO2 acid aerosols, dioxides of nitrogen, ozone and diesel particles. Pathogenic hypotheses concerning the undesirable effects of atmospheric pollutants on the respiratory system are considered.     

托辊机床设计应用

主要介绍托辊加工机床设计目的及设计原理,陈述了刀具的结构与装夹方式、动力来源.从理论上阐述了影响产品质量的因素,并提出防止产生质量问题的措施,大胆使用尾座为刀体的动力头,满足了一次装夹两头成型的加工要求.     

Machining of Machine Elements Made of Polymer Composite Materials

The machining of the machine elements that are made of polymer composite materials (PCMs) or are repaired using them is considered. Turning, milling, and drilling are shown to be most widely used among all methods of cutting PCMs. Cutting conditions for the machining of PCMs are presented. The factors that most strongly affect the roughness parameters and the accuracy of cutting PCMs are considered.     

Some features of the ultrastructure of the coenecium of Rhabdopleura compacta

The coenecium of Rhabdopleura consists of a series of tubes, some erect and some repent. These tubes are composed of rings, one stacked within another. The rings are smooth on the inside surface and rough outside. Newly laid down rings are thin and smooth on both surfaces, fibrous material is laid down on the external surface during growth in thickness by the cephalic shield of the zooid. The erect tubes remain discrete, but the repent tubes, which are attached to the substratum can become incorporated in a mass of secreted material. The external vertical fibres cross several rings and probably serve to anchor the stack. Besides these fibrils that run for several segments, there are other shorter fibres that run along the length of each cylindrical ring, and are not continuous across the rings. These long and short fibres have features in common with those found in the graptolites.     

Change of critical events of cleavage fracture with variation of microscopic features of low-alloy steels

Two steels with different contents of carbon and impurity elements are heat treated to produce various ferrite grain sizes. Four-point-bend (4PB) tests of specimens are carried out at low temperatures. Microscopic observations of metallographic sections and fracture surfaces combined with finite-element model (FEM) calculations are made in detail. Results of the investigation reveal that the critical event for cleavage fracture changes from a crack-propagation-controlling model to a crack-nucleation-controlling model with increasing grain sizes to very large ones and decreasing carbon and impurity element contents. The cleavage initiation sites also move closer to notch roots, which in the case of fine grains locate around the positions where the peak tensile stresses are reached. The mechanism of changes of critical events and the cleavage initiation sites are analyzed.     

Models of integration given multiple sources of information.

Several models of information integration are developed and analyzed within the context of a prototypical pattern-recognition task. The central concerns are whether the models prescribe maximally efficient (optimal) integration and to what extent the models are psychologically valid. Evaluation, integration, and decision processes are specified for each model. Important features are whether evaluation is noisy, whether integration follows Bayes's theorem (S. M. Stigler, 1986), and whether decision consists of a criterion rule or a relative goodness rule. Simulations of the models and predictions of the results by the same models are carried out to provide a measure of identifiability or the extent to which the models can be distinguished from one another. The models are also contrasted against empirical results from tasks with 2 and 4 response alternatives and with graded responses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)