精轧区热轧带钢温度场的数值模拟

通过对带钢热连轧过程传热关系的分折，利用有限差分法建立了带钢三维温度场的数值计算模型。结合攀枝花钢铁集团公司热轧生产线的实际条件，利用该模型模拟了精轧区带钢的温度场，并与实泅结果进行了比较，验证了模型的可靠性。在此基础上，讨论了终轧厚度和轧制速度对带钢温度场的影响，为改进和优化轧制工艺提供了理论依据。     

X46级管线钢热连轧过程中温度场及平均流变应力的预测

采用有限元计算模型和实测轧件温度以及精轧各道次的轧制压力值，对不同边界条件下的传热系数和塑性功转热率进行了优化计算，得到了轧件断面温度场。在此基础上考虑了再结晶等因素，建立了计算精轧过程中应力一应变曲线的流变应力模型，并利用该模型对X46级管线钢精轧各道次的流变应力进行了预测。结果表明：该模型的计算结果与用Sims法计算的结果吻合较好，能真实反映工业生产的实际情况。     

TSCR生产X65管线钢过程的再结晶研究和MFS预测

在有限元差分法模拟温度场基础上,预测了管线钢TSCR过程的组织演变及断面分布规律,建立了考虑晶粒尺寸和再结晶影响的平均流变应力模型,提出了细晶轧制的工艺窗口.随着温度降低,精轧后几道次几乎没有再结晶发生;加大精轧区前两个道次压下量或者降低精轧入口温度可实现奥氏体晶粒细化;模型预测值与工业实测数据吻合良好.     

热连轧带钢终轧温度预报模拟软件开发

 在传统热连轧精轧机组温降模型基础上,开发了带钢热连轧终轧温度预报软件。将带钢在中间辊道和精轧区内按主要冷却方式的不同划分为多个传热区域,并以带钢粗轧出口温度实测值为起点,依次累加计算带钢在精轧区内的温降。使用该软件计算的带钢恒速轧制温度预报结果与现场实测值吻合较好。     

高速线材10道次精轧过程的有限元模拟

通过对钢厂高速线材热连轧过程的传热分析,借助ABAQUS软件建立了线材与轧辊的3维热机耦合模型,对42A钢(0.39%～0.46%C)从Φ16 mm精轧至Φ5.5 mm轧材的10道次精轧过程的温度场,应力-应变场和轧制力进行了模拟。得出精轧后轧件心部温度升高130℃,表面温度降低10℃,轧件降温主要是轧件的热辐射和水冷造成的。10道次轧制力的计算值与实测值的相对误差为1.88%～4.50%。     

铁素体SUS430粗轧模型优化与完善

根据铁素体SUS430的加热及变形特点,结合1 780 mm热轧生产线特点,重点从粗轧工艺模型方面介绍了优化粗轧轧制道次及提高宽度控制精度两方面内容：通过减少粗轧道次,缩短粗轧轧制时间,提高精轧开轧温度,以提高热轧产能;另外,在铁素体SUS430坯料宽度波动比较大的前提下,通过优化热轧宽度模型控制参数来提高带钢的宽度控制精度。结果表明对原有不锈钢430轧制工艺的优化与完善,进一步提高了不锈钢430的产能及产品质量。     

层流冷却过程中带钢温度场的数值模拟

建立了温度与相变耦合的二维有限差分预测模型,并对带钢轧后冷却过程带钢厚度和宽度方向的温度场进行了模拟计算.根据连续等温转变实验曲线,采用Avrami方程和Seheil的可加性法则来计算带钢相变潜热,实现温度和相变耦合求解,计算结果和现场实测结果吻合.     

鞍钢半连轧厂过程自动化精轧数学模型

一条粗轧热带钢进入精轧区通过六座连轧机架轧制,实现自动化功能代替人工手动操作,轧出符合温度、宽度和厚度目标值要求的精轧热带钢.上述这些都是由精轧数学模型程序来完成的。精轧数学模型有七个功能程序,即轧制策略、轧制表预计算、入口校正、温度再调节、轧制表后计算、轧制表自适应、负荷再分配.对这七个功能程序做了详细介绍。     

带高压水除鳞换热的带钢粗轧过程温度场数值模拟

热带钢在轧制前通常需用高压水去除氧化铁皮。随着高压水对带钢表面冲击强度的增加,除鳞效果明显增强,带钢的温度也显著降低。影响带钢温度变化的因素复杂多变,其中尤以高压水的影响较显著,因此研究带钢在高压水除鳞过程中的温度场分布,对于了解带钢粗轧过程中的温度变化、合理制定后续精轧工艺非常必要。笔者将有限元数值解法与实验结果相结合,研究了高压水冲击强度与带钢换热系数之间的对应关系,得出了换热系数计算模型。将该模型应用于宝山钢铁集团公司2050mm热带钢粗轧机组进行模拟计算。结果表明模拟值与现场实测值吻合良好。     

几何模型更新方法在板带热连轧精轧道次中的应用

为了更好的对精轧过程进行数值模拟,提供更为合理的轧制参数,以LS-DYNA软件中的单元更新方法模拟了精轧过程。建立好第1道次轧制模型并数值模拟,对第1道次计算结果进行了分析。以第一道次轧制后的单元形状为基础,进行单元更新,改变边界条件和载荷,对第2道次进行数值模拟,用同样方法对3～7道次进行数值模拟。该方法在准确地模拟了精轧过程中板带变化的同时,为各精轧道次提供准确的轧制参数。     

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.