莱钢铸铁机链板使用可靠性攻关实践

针对莱钢57 m铸铁机链板及其耐磨套磨损速度过快、耐磨套固定不牢等问题,采取增加链板磨损面厚度、对耐磨套进行调质处理、耐磨套安装采取过盈配合等措施,提高了链板和耐磨套的抗磨损性能、牢固可靠性,从而提高了铸铁机链板的整体使用寿命。     

443超纯铁素体不锈钢热轧卷断带原因分析

443热轧板在热退火酸洗线生产时卷尾部经常发生脆断事故,给不锈钢冷轧生产带来了极大的损失。本文从常温力学性能、韧脆转变温度、金相组织、夹杂物等级、断口SEM微观分析等方面研究认为该钢种卷尾部断裂为低应力弯曲脆断,常温断口状态为脆性解理断裂,夹杂物是产生低温脆断的裂纹源。     

浅谈热链板输送机结构改进

针对公司链板输送机出现的链板磨损、断裂等问题进行分析,改进现有的链板结构;改进链板机托轮结构;改进轴、轴套和内、外链板结构。实践证明,改进后的链板输送机结构较合理,节约了设备的检修费用和备件成本,降低了检修人员的劳动强度,提高了设备作业率和使用寿命。实施改造后,取得了很好的效果。     

钢包回转台高强度连接螺栓的脆断分析与设计改进

本文介绍了钢包回转台高强度连接螺栓在静载低应力状态下脆断的实例，证实了断裂原因是由于高强度合金钢裂纹敏感型突发性脆断所致。并对钢包回转台高强度连接螺栓的设计提出了改进意见。     

Ф32mm HRB500E弯曲脆断原因分析

文章对φ32mmHRB500E弯曲脆断和弯曲正常的钢材取样进行了对比检测分析,发现弯曲断裂样强度高于弯曲正常样,总伸长率低于弯曲正常样。认为晶粒度粗大是导致弯曲脆断的主要原因,并分析了弯曲断裂样晶粒粗大产生的原因。     

优化连铸工艺 提高硬线盘条质量

分析了82B、77B系列盘条在拉拔过程中常出现的脆断现象，指出碳偏析、缩孔、表面横裂缺陷是导致盘条在拉拔过程中发生断裂的主要因素。通过优化连铸工艺，提高了盘条的质量，降低了用户在使用过程中的断丝率。     

挖掘机斗杆断裂的力学分析

对挖掘机斗在不同工况条件下受力状况进行了分析，并通过测试，将１５ＭｎＶ和ＨＱ８０钢动态力学性能进行了对比，认为斗杆早期断是由所用材料的动态断裂特性所决定的，测试结果证明：ＨＱ８０钢抗脆断裂优于１５ＭｎＶ钢。     

热轧带肋钢筋脆断的原因

本文分析南方钢厂生产热轧带肋钢筋断裂的原因，认为加强废钢管理，合理加入废钢量，控制Ｃ，Ｍｎ，Ｓｉ的成分，防止Ｃ当明偏高和轧制加热高温度是解决脆断的办法。     

SWRH82B盘条拉拔断裂原因分析及工艺改进

针对用户在拉拔过程中出现了多次断裂现象,对断口形貌、组织和成分分析,得知铸坯碳偏析是造成82B盘条拉拔脆断的主要原因,且拉拔脆断与B类脆性夹杂物也有一定关系。同时提出采用无铝脱氧工艺、降低铸坯碳偏析工艺及合理控制轧后冷却速度等改进措施。     

平台钢.CF钢韧性断裂研究中揭示空穴的方法

本文介绍的“液氮脆断法”,是研究金属材料韧性断裂过程中空穴行为的重要手段之一。它简便易行.成功率超过了其它方法     

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。     

焦炭热性能指标意义浅析

通过对焦炭在高炉内的历程及其变化规律的剖析,阐述焦炭热性能指标的意义,形象地把焦炭在高炉内的损耗分为三部分(M1,M2,M3)。指出M2对焦比及焦炭价格有一定的指导作用。     

Results of treatment of cancer of the cardia

Cancer of the cardia is traditionally discussed with cardiac cancer of the lower portion of the esophagus and upper gastric cancer invading the esophagus, and the specific characteristics of cancer of the cardia have never been clearly defined. We reviewed the outcome of 172 patients with adenocarcinoma of the cardia who had undergone radical surgery between 1949 and 1994 in the Division of Gastrointestinal Surgery of the Cancer Institute Hospital. The centers of the tumors were located within 2 cm above and below the boundary between the esophagus and the stomach, and their longitudinal diameter was less than 8 cm. We divided the patients into an early period (1949-1979; n = 79) and a late period (1980-1994; n = 93), and focused on the historical transition. There were no differences in patient gender or histology between the two periods. However, the late period was associated with fewer cases of esophageal invasion and shorter longitudinal diameter, as the age of the population advanced. The number of advanced cancers such as the localized and infiltrative type had decreased, and early cancer and early clinical stage had become more common, but despite the fact that the number of early cancers had increased, extended dissection, such as thoracic and paraaortic lymph node dissection, was performed more frequently. By clinical stage, the long-term outcome markedly improved in Stage I patient in the late period, and tended to improve in Stage II and III patients. This appears to have been attributable to the prevention of micrometastasis by extended dissection, although the number of early cancers is another major potential cause. There were no differences in the outcome of Stage IV patients between the two periods, and further advances in multimodality therapy must be awaited. The range of resection is basically proximal gastrectomy, and if there are adequate indications, the prognosis is favorable. In view of the status of lymphatic flow and lymph node metastasis, and long-term results, lateroaortic lymph node dissection is important. Since the number of early cancer patients has been increasing, if intraabdominal recurrence is prevented, intrathoracic lymph node dissection will contribute greatly to the outcome of such patients.     

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.     

浅析《野草》的版画特征

鲁迅先生一生热爱美术作品,对版画中木刻兴趣尤甚.<野草>作为其"写心之作",亦呈现出一些与木刻版画一致的审美特征:一是具有木刻版画的色彩特征,多对比、多冷色,有阴郁的美感;二是具有木刻版画的力度特征,环境描写、人物刻画处处刀锋毕现,遒劲有力,有一种"力之美".     

四辊破碎机车刀架的改造

针对四辊破碎机车刀架车削中存在的几个问题,详细介绍了电动车刀架的结构和工作原理,建立主要设计参数的数学表达式,并进行适当的分析。改造后,这种电动车刀架运行平稳、可靠、方便、省力,取得了预期的效果。     

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.