防止椭圆-圆孔型系统轧件发生扭转的措施

八钢小型轧钢厂中、精轧采用椭圆一圆孔型系统在生产过程中多次发生轧件扭转，经分析认为圆孔型入口导卫磨损的程度直接影响轧件扭转程度和产品质量。为防止轧件产生扭转，将入口导卫椭圆导辊改成菱形导辊，解决了轧件扭转的问题。     

H型钢侧向矫正中的扭转问题研究

应用弹性和弹塑性扭转理论,对H型钢在侧向矫正中的扭转变形进行了计算,给出了扭矩与扭转变形(扭转角)之间的关系。通过型钢所受扭矩大小或产生的单位扭转角的大小可以判断轧件产生的扭转变形的类型。通过典型规格H型钢的扭转研究,认为侧向矫直中的侧向扭矩将主要引起轧件的断面变形和腹板上接触力分布的变化。轧件的整体扭转力矩仅占其中很小部分,而纯粹的侧向矫直则因扭转失稳无法完成。     

棒线材粗中轧多线大扭转辊的设计与改进

在轧辊呈水平布置的棒线材粗、中轧,由于轧件断面较大,轧件扭转时需要施加较大的扭转力,对扭转辊的设计和使用都提出了较高的要求.本文介绍了安钢Φ260mm机组多线大扭转辊装置的设计及使用情况.改进后,一套大扭转辊能连续上线使用一个月,较原来的小扭转辊寿命提高90倍.     

球扁钢轧制扭转变形行为的试验研究

球扁钢由于自身形状尺寸、外在轧制条件、工艺参数的影响,在轧制过程中容易出现扭转变形缺陷.为了探究轧制工艺对球扁钢轧制中扭转变形的影响,本实验运用正交实验法研究轧制压下量、轧制润滑条件、轧件长度三者的综合影响.利用正交原理对试验结果进行极差分析、方差分析,探寻球扁钢在轧制的扭转变形规律,找出其中存在的关系.试验结果表明:球扁钢在轧制过程的扭转变形与轧制压下量和轧件长度有关,而与润滑条件无明显关系.其他条件一定时,在粗孔第二道次时取压下量为轧件原始厚度的21!,轧件长度取轧件原始厚度的10倍进行轧制,能够明显减少球扁钢的扭转变形.     

扭转辊的设计与应用

在粗轧机组全水平布置的线棒材连轧生产线中,轧件从随圆孔进入圆形孔需要扭转,采用扭转辊取代扭转导卫,提高抗冲击性,减少少堆钢事故。本文着重介绍了扭转辊的设计方法和应用效果。     

出口滑动扭转导卫的设计与应用

通过对轧件在滑动扭转导卫中的受力分析,论述了扭转导卫有关参数的确定,并简要介绍了新型复合材料导卫的制造加工和使用。     

异型门架型钢轧制过程稳定性模拟

借助有限元分析软件对C160规格异型门架型钢的非对称切分孔轧制过程进行模拟仿真,并对轧制过程的翘扣头、弯曲、扭转等稳定性进行模拟。对稳定轧制阶段截面云图中应变分布、变形及延伸进行分析,并进行生产实施,结果表明：轧制过程中,稳定阶段轧件截面下部变形及延伸大于上部应变,造成轧件上翘;左侧变形及延伸大于右侧应变,造成轧件向右侧弯;对角的应变分布及延伸相近,轧件没有发生明显扭转。为轧制过程稳定性研究提供了一种方法,对保证轧制顺行、稳定工艺、提高作业率及指导生产具有重要意义。     

连轧机多线整体辊式扭转器

鞍山钢铁公司研制成功一种连轧机多线辊式扭转器。该扭转器主要由框架、压下螺丝、轴承、轴杆、扭转辊、导槽和调整斜铁等组成。整体安装在轧机出口的牌坊架内。为适应不同断面轧件的要求,其两个扭转辊的径向及轴向尺寸可分别靠压下螺丝和调整斜铁调整,并且在扭转辊与轴杆间采用滚动轴承和甘油润滑。该装置结构简单、紧凑、固定牢固、工作可靠、调整灵活、换辊方便;摩擦系数小,承受扭矩大;孔型合理、开口度大、初始扭转角小、变形缓和、轧件稳定,适用范围广。因此,减少了生产事故,提高了作业率,减少了轧废,从     

楔横轧凸轮轴金属流动规律的有限元分析

通过有限元仿真楔横轧凸轮轴时在轧件上取跟踪点,跟踪这些点的位置变化情况来揭示轧件内金属的详细流动规律.因凸轮体小圆端部分在轧制过程中所受模具挤压较小,其金属轴向流动和径向流动较其他变形区小,这种金属流动的不均匀性会影响轧件成形质量;轧制过程中因凸轮体小圆端与模具上凸轮凹槽产生啮合作用,这一作用降低了模具对凸轮体小圆端部分的周向扭转力,因此凸轮体小圆端部分的周向扭转相对较小.轧件凸轮体部分为非圆截面,此部分各向金属流动不均匀,造成凸轮体部分心部金属偏移量比其他部分大.     

履带钢轧制过程有限元仿真

履带钢断面形状复杂,轧制过程中容易出现扭转、翘曲、侧弯等现象,影响轧制的顺行.利用仿真软件建立了履带钢切深孔轧制过程有限元仿真模型,研究孔型参数对轧件扭转、翘曲及侧弯的影响规律.针对履带钢切深孔轧制扭转严重的问题,优化孔型参数,使履带钢切深孔轧制过程扭转角从135.6°减小到13.85°,满足后续道次正常咬人的要求,保证了生产的顺利进行.     

Standards of weight and height for Ayrshire, brown Swiss, and milking shorthorn heifers

To develop a modern appraisal of growth for Ayrshire, Brown Swiss, and Milking Shorthorn dairy heifers, data on heart girth and height at withers were collected from 1279 Ayrshire heifers (33 herds), 1819 Brown Swiss heifers (46 herds), and 565 Milking Shorthorn heifers (20 herds), ages 1 to 25 mo, in herds located throughout the US. Means and standard deviations were determined for height and heart girth for each month of age. Third-order regressions on age were fitted to the means to describe height and heart girth. Estimated mean height and heart girth at 6, 12, 18, and 24 mo, in centimeters, were for Ayrshire 98.7 and 118.4, 114.4 and 145.9, 122.8 and 163.2, and 127.6 and 176.4; for Brown Swiss 102.6 and 122.3, 199.4 and 151.3, 128.7 and 168.8, and 134.0 and 182.0; and for milking Shorthorn 98.0 and 119.4, 113.6 and 148.6, 122.6 and 166.6, and 127.7 and 179.9, respectively. These data can be useful to evaluate the heifer rearing program with respect to the growth rates of heifers on an individual farm.     

Roles for psychologists in emerging models of school-related health and mental health services.

Describes contributions of school, clinical, community, and health psychology to emerging school-based and school-linked health and mental health service delivery models. The author contends that these 4 areas integrate well to inform the development and targets of health service delivery approaches in and linked to the schools and to set the stage for defining the emerging and future roles of psychologists providing health and mental health care in these contexts. Emerging and future roles of psychologists as health care providers through schools include roles in development, implementation, and administration of these models, direct and indirect service provision, interfacing of health and educational outcomes, and applied research and evaluation activities. Implications for the education and training of current and future psychologists are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dietary intakes of middle-aged European, Maori and Pacific Islands people living in New Zealand

AIM: To compare dietary intakes of Maori, Pacific Islands and European men and women in New Zealand. METHODS: A food frequency questionnaire was used to calculate nutrient intakes of 5523 New Zealand workers aged 40 years and over (3997 men, 1524 women) from a cross-sectional survey carried out between 1988 to 1990. RESULTS: Compared with European men and women, Maori women and Pacific Islands men and women consumed larger amounts of total energy per day. Age-adjusted nutrients expressed as percentage contribution to total energy intakes showed that Maori and Pacific Islands men and women consumed less carbohydrate, fibre and calcium, and more protein, fat, saturated fat and cholesterol than European men and women, respectively. These results were consistent with fewer servings of cereal and cheese per month, and more servings of red meats, fish and eggs in Maori and Pacific Islands participants compared with Europeans, after adjusting for age and total energy intakes. Pacific Islands men and women also consumed more servings of chicken, fewer cups of milk and fewer servings of fruit per month compared to Europeans. Maori men and women consumed more slices of bread and fewer servings of vegetables per month compared to European men and women. CONCLUSIONS: There were striking differences in dietary habits, food selections and cooking practices between European, Maori and Pacific Islands participants. Dietary intakes of Maori workers were closer to those of Europeans than those of Pacific Islands participants. Ethnic differences were due to larger portion sizes and increased frequency of most foods in Maori and Pacific Islands participants.     

Heavy metal concentrations in two populations of crayfish

To monitor the environmental contamination of heavy metals in Tuskegee Lake (TL) and National Forest Creek (NFC), Tuskegee, Alabama, adult crayfish muscle and exoskeleton and sediment samples were collected and analyzed for Hg, Pb, Cd, Cu, Co, Ni and Zn. In both TL and NFC crayfish Cu and Zn were not different in muscle and exoskeleton; however, Pb and Cd were significantly different. The Pb in exoskeleton and the Cu and Zn in muscle and exoskeleton of TL crayfish were significantly higher than that of NFC crayfish; however, Cd and Ni were not different between tissues or crayfish sources. Levels of Hg and Co were not detectable.     

Employee drug use, demographic characteristics, work reactions, and absenteeism.

Investigated the relationships between employee use of illicit drugs, perceptions of and reactions to the work environment, and employee absenteeism and tardiness above and beyond that accounted for by demographic and work reaction variables. 162 employees in a large work organization completed demographic and background information and assessments of work perceptions and reactions and absenteeism and tardiness. Drug use was assessed with a questionnaire and urine testing. Employee drug use accounted for additional statistically significant variance in overall absenteeism and in absenteeism due to injuries and suspensions, as well as days tardy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Moral aspects of risk and innovation

In all areas of technological innovation and application, there are nontechnical (moral, cultural, religious, political, and regulatory) risk factors and uncertainties that have to be taken into account if research design and introduction of new devices and applications are to be successful. Products and methods will be beneficial to the patient if they meet personal and cultural expectations. Value assessment of individual patients and of cultural preferences and obstacles therefore has to be included in complex technology assessment. Successful recognition and management of moral and cultural risk factors may require changes in governmental regulation and research design and the development of risk recognition competence within professional organizations.     

从氯化浸金稀溶液中提取金、银工艺研究

试验采用C410树脂,对氯化浸金稀溶液进行预分离富集,研究了在静、动态条件下C410树脂对金和银的吸附、解吸性能、饱和吸附容量及杂质的干扰等。在试验最佳条件下,对某矿样氯化浸出液,金、银的吸附率分别达99．89％、86．5％,解吸率分别达99．32％、99．72％;解吸液经化学沉淀、溶金银、还原,获得的金、银的纯度达99．995和99．993％。     

能源产品投入产出研究与应用

介绍了能源产品投入产出的研究与应用,通过外购能源和自产自耗能源产品技术经济分析,找出其依存关系,科学合理地计算能源生产、消耗、成本数据,为能动中心更好地生产组织、能耗控制与决策提供可靠的依据。     

智能化钢铁制造流程信息物理系统的设计研究

 现代钢铁制造流程是集成烧结、球团、焦化、炼铁、炼钢和轧钢等多工序过程的耗散结构体系。钢铁制造流程是在物质流、能量流和信息流协同运行的条件下,完成一系列复杂的冶金过程和转变。探讨了对钢铁制造过程物理本质以及运行特征的认识和研究,提出了现代钢铁制造流程物理系统的设计理念和方法。阐述了流程工程动态精准设计体系在钢铁冶金工程设计中的应用,讨论了智能化钢铁制造流程的系统层次和构建理念。着重论述了钢铁制造流程信息物理系统的内涵和架构,提出了静态物理系统与信息系统集成、耦合、协同的设计理念和方法,论证了现代钢铁制造流程信息物理系统的智能化设计思路、程序和应用实践。     

Influence of client preparation and problem severity on attitudes and expectations in child psychotherapy.

Assessed the effects of client preparation and problem severity on children's and parents' understanding, attitudes, and expectations of child psychotherapy. 38 children (aged 6–12 yrs) with 1 of their parents served as Ss. Half of the children and parents received preparation information, and the other half were not prepared. Following preparation vs no-preparation procedures, children and parents completed questionnaires assessing problem severity, knowledge of and attraction to therapy, and prognostic expectations. Parents completed the Child Behavior Checklist, and therapists rated problem severity and expectations for treatment outcome. Results indicate that preparation increased children's and parents' knowledge of therapy, attraction–receptivity to therapists and treatment, and expectations for therapy outcome. Children and parents were found to be quite attracted and receptive to psychotherapy and to have very positive expectations for treatment outcome. Findings indicate that therapists saw the children's problems as more severe and had lower prognostic expectations than did children and parents. No relation was found between problem severity and attraction–receptivity to treatment or expectations for treatment outcome. (36 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)