减少管式加热炉散热损失的经济性分析

提高管式加热炉的热效率,减少燃料消耗,能够达到节能减排的目的。减少管式加热炉炉体散热损失是提高加热炉热效率的方法之一。以两种常用的典型炉型为例,进行了炉墙外壁温度经济性计算与分析,认为在现行设计标准的基础上降低炉墙外壁温度,减少加热炉散热损失,提高加热炉热效率是可行的,在多个炉墙外壁温度的比选中,按照3年收回增加的投资成本考虑,确认炉墙外壁温度为60℃最为经济合理。     

50 t转炉一维稳态温度场的分析与计算

对重钢50 t转炉进行了炉壳(炉身段)温度场分析,计算表明转炉隔热层石棉板的厚度为30 mm时,炉壳温度就能控制在360℃以内,低于炉壳材质的蠕变温度.     

矿井风流温度的近似计算

本文根据井下风流温度主要受到围岩散热,高度变化和含湿量变化影响的假设,导出一井下风流温度的近似计算方法。该方法经实例计算和与其他方法比较表明,具有计算过程简单、收敛速度较快和计算结果准确的优点。无论是在新设计矿井和生产矿井的风流温度计算中均可应用。     

渣对钢液温度的影响

开发了渣表面散热模型，定量分析了渣层内温度变化规律，以及表面散热情况，比较了模型计算结果与大冶钢厂现场实测值，指出保证５０ｍｍ的渣层厚度有利于减少钢液温度损失，开发的模型可作为钢液温度控制的一部分指导现场生产。     

转炉炉壳的蠕变变形模型

转炉炉衬采用镁碳砖后，炉壳温度可达450℃或更高，造成炉壳蠕变变形，通过转炉炉壳蠕变变形影响因素的分析和ANSYS软件建立了炉壳蠕变变形的计算模型，有限元模拟计算结果与现场测量值基本吻合。     

八流中间包耐材蓄热对中间包钢液温度的影响

对八流40 t中间包烘烤及浇钢过程的包壁与钢液温度进行了数值模拟计算与20CrMnTiH钢200 mm×200 mm坯连铸现场实测。结果表明,模拟计算烘烤期间中间包耐材升温缓慢,浇钢后中间包内衬耐材升温加快,第3炉外壁温度397℃,达到热平衡;第2炉结束时,计算两侧与中部钢液温度较第1炉对应位置分别升高5.2、1.5℃,计算边流与中部流钢液温差4.8℃,实测第2炉边流间与中部流间钢液温度相差4℃,中间包钢液温度均匀稳定,计算值与实测值趋势一致;烘烤包温度由900℃提高至1000℃时,第1炉中间包钢液温降减慢,水口出钢温度略增,各流间温差减少。     

转炉出钢温度控制技术的研究与实践

钢水热损失主要为钢水的辐射散热、对流传热和钢包、中间包耐火材料的吸热。分析了转炉出钢温度过高的危害及原因。通过提高合金烘烤温度,开发应用新型保温覆盖剂,采用钢包综合砌筑技术、智能吹氩和中间包保温等措施,有效降低了转炉出钢温度,平均出钢温度降低10℃以上。炼钢系统低温均衡可控,产品质量提升,并且冶炼成本降低。     

降低转炉出钢温度的实践

钢水过程热损失主要为钢水的辐射散热,对流传热和钢包、中间包耐火材料的吸热。为了减少钢水的过程温降,相应采取了一系列措施：优化钢包保温层,降低包衬的导热系数,减轻包衬的热损失;对脱氧合金化用合金进行烘烤,提高合金加入钢水前的温度;大包加保温盖,实施全程保护浇注等。改进后,平均出钢温度降低20℃以上。     

管式炉炉体外壁温度的经济设置

针对目前管式炉炉体外壁温度越来越低的要求,由过去设计不大于82℃降至目前的要求60℃设计。本文的目的是探讨管式炉炉体外壁温度设置的合理性(管式炉炉体衬里厚度设置的合理性),因为在炉膛温度一定、环境条件一定的前提下,炉体外壁温度由管式炉炉体衬里厚度确定。通过算例,给出衬里厚度设计的经济厚度,对目前加热炉炉体外壁温度的合理设计具有参考价值。     

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)     

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.     

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.