高球比炉料结构下镁质球团的冶金性能研究

为了优化高炉炉料结构,增加镁质熔剂性球团矿入炉配比(球比),对不同碱度(R)镁质熔剂性球团冶金性能和高炉炉料结构熔滴性能进行研究。结果表明:白云石的粘结作用,使得镁质熔剂性球团生球性能明显改善;随着R增大,焙烧球中Mg~(2+)进入磁铁矿晶格中并占据了铁离子扩散产生的空位,并生成铁酸镁和钙镁橄榄石,降低了Fe_2O_3再结晶固结能力,使球团的强度降低,球团还原过程中Mg~(2+)能均匀分布在浮氏体内,使得还原膨胀率逐渐降低;还原度指数在R=0.56时降低明显,但随着R增大还原度指数明显升高,有利于还原;单一镁质熔剂性球团的软化熔滴性都有不同程度的改善,R=1.2时球团性能最好;高球比综合炉料软化熔滴性均有明显改善,炉料结构为25%烧结矿+75%球团矿时效果最好。综合考虑,球团R不宜过高或过低,应控制在1.0左右。     

配加高镁球团矿高炉炉料结构的研究

为了改善炉渣的流动性,在烧结矿中配加MgO,但过量的MgO会使烧结矿质量变差。分析了不同含量的MgO对球团矿和烧结矿性能的影响,确定采用高镁球团矿与低镁烧结矿作为新的高炉炉料结构。利用某厂高炉进行新炉料结构的工业试验,对高炉冶炼过程的各个参数进行检测,发现采用新炉料结构后,高炉的各个参数都有所改善,炉况稳定。     

低硅含镁球团矿抗压强度及冶金性能

提高入炉原料品位降低硅含量,改善冶金性能是高炉精料的主要方向。研究了低硅球团矿的还原膨胀率及MgO对低硅球团矿抗压强度和冶金性能的影响。研究结果显示,低硅球团矿虽然具有品位高,脉石含量低等优点,但随着SiO2含量的降低球团矿还原膨胀率恶化,影响高炉冶炼。低硅球团配加含镁添加剂可以有效控制还原膨胀率,同时改善球团矿的还原度和熔滴性能。球团矿SiO2的质量分数低于2%时,还原膨胀率在60%以上;当MgO的质量分数提高到2.15%以上时,还原膨胀率能降到20%以下,但随着MgO含量的增加低硅球团矿抗压强度下降,需要提高焙烧温度,才能形成稳定的铁酸镁,改善抗压强度。MgO的质量分数为2.15%时,焙烧温度要提高到1 270℃,MgO的质量分数超过2.8%以上时,焙烧温度需要提高到1 300℃。     

高镁碱性球团矿冶金性能试验研究

为了优化唐山建龙高炉炉料结构和改善镁质酸性球团矿质量,运用Fact Sage热力学模拟软件探索了球团焙烧过程中液相量的变化规律,同时采用本地磁铁矿为原料,通过配加镁基、钙基熔剂,研究了MgO含量及碱度对高镁碱性球团矿冶金性能的影响规律。结果表明:固定MgO含量为1.0时,随着碱度提高,球团中铁酸钙生成量增多,同时铁酸钙占总液相量的比例增加;荷重软化初始温度升高,软化区间先变窄后变宽;低温还原粉化及还原性呈先上升后降低的趋势,并在碱度为1.0时达到最佳。固定碱度为1.0时,随着MgO含量增加,铁酸钙生成量减少,其所占总液相量的比例也降低;软化初始温度升高,软化区间先变窄后变宽;低温还原粉化及还原性能得到改善。总体而言,碱度控制在1.0且MgO含量为1.0%时,高镁碱性球团矿的冶金性能最优。     

LKAB公司加橄榄石球团矿的生产和使用

对含硅量很低的磁铁精矿,进行了添加不同数量的含MgO物质的篦式罐球团试验,其加热方式也各不相同。结果表明,添加了MgO之后,除冷强度外各项冶金性能的改善更为明显。它的熔融特性与不同碱度的烧结矿也作了比较。在一链篦机——回转窑的设备中,生产了添加橄榄石的高MgO球团矿。这些球团矿在三座高炉中与烧结矿配合使用的结果表明:LKAB橄榄石球团矿作为高炉炉枓其性能优于酸性球团矿。     

球团配加镁质熔剂及新型皂土试验

为生产含MgO的镁质球团用来替代烧结矿中MgO,确保高炉造渣所需的适宜的MgO质量分数,考察了在球团生产中添加一种新型球团黏结剂(新型皂土)和一种氧化镁质熔剂(镁石粉)时,对造球焙烧及球团矿冶金性能的影响。试验结果表明,镁质球团生球落下强度有所提高,350℃时未发生爆裂。配加新型皂土可提高球团品位,降低Si O2质量分数。镁质球团的低温还原粉化指标和体积膨胀率指标均有所改善。而且,软化温度升高,软化温度区间变窄,有利于软熔带由高炉上部往下部移动,改善高炉透气性。在保证综合入炉铁料MgO质量分数不变的条件下,当烧结矿自然带入的MgO质量分数为1.2%时,球团矿中的MgO质量分数大于1.90%,可满足高炉要求。     

碱性含镁球团矿的应用及合理炉料结构研究

使用碱性含镁球团矿可提高氧化球团矿质量,进而改善高炉生产指标.从理论上分析了碱性含镁球团矿的冶金性能,并探讨了包钢高炉炼铁合理的炉料结构,研究结果表明:碱性含镁球团矿中合理的MgO的质量分数为1.8%,烧结矿中合理的MgO的质量分数为1.8%、碱度为1.7.依据包钢现有的资源条件分析了通过添加轻烧白云石细磨粉,制作含镁碱性球团的可行性.     

高镁质球团矿的生产实践

烧结矿中MgO含量的提高,烧结成品率、垂直烧结速度、转鼓指数,机械强度均出现降低的现象,提高MgO含量对改善烧结矿的产量、质量十分不利。将烧结矿中Mgo转移到球团矿中,可以提高烧结矿质量,改善烧结矿冶金性能;同时球团矿中MgO可以形成镁橄榄石和偏硅酸镁等高熔点相,提高球团矿的冶金性能。通过实验室实验,结合工业试验,确定了配加不同配比镁质添加剂与皂±的造球混合料指标、生球指标、竖炉操作制度,为生产高镁质球团矿提供了保障,高炉配加高镁质球团矿后,综合炉料冶金性能明显改善,将球团矿与烧结矿在软熔温度区间上的差异缩小,利于高炉软熔带厚度的减薄,利于高炉透气性提高及高炉软熔带的下移。对于高炉壁面温度的稳定、热负荷的降低以及扩大间接还原有有利影响,对高炉炉况的稳定、燃料消耗的降低有明显促进作用。     

高炉高(MgO)渣性分析及炉料结构优化探讨

针对近年来昆玉钢铁高炉在使用高MgO炉料配比存在的问题及高炉生产状况,开展了高炉高(MgO)渣性能研究及高MgO炉料性能及结构协同优化。认为昆玉高炉炉料结构应依据现有生产装备及进口高MgO铁矿资源条件下,合理调配高MgO精矿在烧结与球团中的比例,逐步实现以高碱度低MgO烧结矿配加高MgO酸性球团矿的综合炉料,在满足高炉炉况稳定顺行的基础上,提高高MgO铁精矿使用量,达到炉料结构功效最大化,生铁成本最优。     

高炉使用含碳复合炉料的原理

 高炉炼铁正朝着高产、低污染、低能耗的方向发展,为了实现这一目标,包括高炉使用含碳复合炉料等一些革新的炼铁技术已经被提出或实际应用。铁焦、热压含碳球团是将铁矿粉和煤粉按一定比例混合后制成的新型含碳复合炉料。研究结果指出,含碳复合炉料相比于传统的高炉炉料（烧结矿和球团矿）具有高温强度高、还原性能好以及原料适应性强等优势。阐明了高炉使用含碳复合炉料的基本原理,介绍了铁焦制备的工艺流程及应用情况,重点进行了热压含碳球团制备工艺流程、冷态冶金性能、高温冶金性能、高炉使用热压含碳球团等试验研究,最后利用多流体高炉数学模型对高炉使用热压含碳球团操作进行了模拟研究。研究表明,高炉使用一定量的含碳复合炉料可以降低热空区温度,增加产量,降低焦比,高炉热利用效率明显提高,操作性能得到有效改善。     

转炉炉壳热应力分析

根据实际转炉建立实体模型。以有限元为手段,考虑了炉衬和炉壳材料的物性参数随温度变化的特点和炉衬与炉壳之间膨胀间隙,计算了转炉炉壳在温度载荷和炉衬膨胀压力同时作用下的热应力。所得结果可为转炉炉壳设计提供依据。     

Quality of life of relatives of mental patients

Usage of quality of life of psychiatric patients' relatives as the parameter of estimation of the quality of psychiatric care is considered. By means of standard questionnaire elaborated by the authors as well as by means of both individual and group conversations the quality of life was analyzed in 40 relatives which lived together with psychiatric patients. Different spheres of their life and difficulties (financial, social-psychologic, production) were examined in families with such patients. The defects of psychiatric care that had direct influence on the quality of life of the psychiatric patients' relatives are outlined.     

Effect of antibiotics of chemotaxis of human leukocytes

The effect of 20 different antibiotics on chemotaxis by human neutrophils was studied. Human leukocytes incubated with chloramphenicol, rifampin, sodium fusidate, and tetracyclines in vitro showed markedly depressed migration. The mechanisms by which these antibiotics affect leukotaxis are discussed.     

Concept of freedom of infection of animal flocks

Totally negative results of epidemiological investigation of random samples do not prove the absence of the infection as the pathogen may be restricted to only a few animals in the herd for a long time. The statement "absence of infection" is critical for such situations. The question is raised, whether the statement "absence of infection" should be generally avoided. Classification of herds and flocks according to the prevalence of the pathogen would be more valid for the implementation of control measures.     

显微维氏硬度测量不确定度评定

对显微维氏硬度测量不确定度进行评定，建立了不确定度计算的数学模型，确定了影响实验结果的各项因素，计算出了各因素的标准不确定度，得出结果的扩展不确定度，并给出最终测量结果的表达式。     

The effect of amount of possession of the trait of hostility on accuracy of perception of hostility in others.

Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparison of rates of infection of two methods of emergency ventricular drainage

The rates of infection of two methods of external ventricular drainage in use at Atkinson Morley's Hospital--namely, (a) percutaneous drainage with Rickham reservoirs and (b) tunnelled ventriculostomies--were compared in this retrospective review. Percutaneous drainage of CSF with Rickham reservoirs was associated with a 27% rate of infection as identified by positive microbiological cultures; tunnelled ventriculostomy catheters had a 10% infection rate. The difference in the infection rate between the two methods was statistically significant (P < 0.015). Other variables examined, including the age and sex of the patients and the reasons for ventricular drainage, were not associated with an increased rate of infection. Most infections from either method were caused by a coagulase negative staphylococcus. The average duration of ventricular drainage before identification of positive cultures was 5.7 days for Rickham reservoirs and 6.0 days for ventriculostomies.