索道线路单筒支架的有限元分析

使用有限元分析软件ANSYS,通过合理简化,建立了某索道线路单筒支架的三维有限元模型;对其在各种载荷作用下的应力强度进行计算;根据分析设计标准,进行应力评定,对类似索道支架的设计和计算有一定借鉴和参考价值。     

矿山装运机械零件的简易实用疲劳强度计算方法

矿山装运机械如各种井下铲运机、装岩机、露天装载机、露天铲运机、自卸汽车等的零件一般受随机载荷的作用,其零件所受的外载荷的振幅是随时间作不规则的变化的,通常称之为变幅载荷,目前一般按下面两种方法来进行疲劳强度计算。 1.通过实测作出该零件的载荷谱,然后进行疲劳强度计算。 2.直接按等幅载荷进行疲劳强度计算。     

150t新型三点球面支撑型转炉的研究

国内外所采用的转炉支撑方式大多为三点球面支撑型式,该支撑形式具有较大的优越性。结合传统的力学分析计算方法,在对转炉运行工况详细了解的基础上,对可能作用于炉壳上的各种载荷进行逐一分析,以可能出现的最大载荷作为计算依据,分析计算炉壳整体综合应力,确定了炉壳在典型工况下的应力分布情况。根据上述情况,研究设计出了三点球面支撑型式的转炉。     

转炉倾动载荷的计算及实测

伟大领袖毛主席教导我们:“一个粮食、一个钢铁,有了这两个东西就什么都好办了。”毛主席的这一指示,指出了钢铁工业的重要地位。在发展炼钢生产中,氧气顶吹转炉已成为一种主要的设备,尤其在中小型企业中更是如此。在设计转炉的倾动装置时,首先需要确定耳轴所承受的各种载荷,其中除了静载荷外,还有动载荷。目前,在一般设计计算中,往往只计算静载荷,并再增加20～30%,算是考虑了动载荷。这样做行不行?我们遵照毛主席关于:“马克思主义者认为,只有人们     

板梁组合结构的有限元分析

本文应用ANSYS有限元分析软件对板和T型材组合结构采用多种不同的构模方法,分析在相同载荷和边界条件下各种不同构模方法的计算结果的区别,从而给出了应用该软件在船舶结构分析中应采用的构模方法。     

基于疲劳累积损伤的X80钢疲劳裂纹寿命研究

为了更准确地预测工程管道在随机载荷作用下的疲劳寿命,要考虑载荷顺序与载荷间相互作用对寿命预测的影响。基于Manson-Halford模型和Corten-Dolan模型,建立了既考虑荷载顺序和荷载间相互作用,又考虑疲劳极限附近荷载的疲劳累积损伤因素。通过该模型可以计算管道在随机载荷下的疲劳寿命,为随机载荷谱下的寿命预测提供了理论依据。将该模型的计算结果与Miner法则、Manson-Halford模型和Corten-Dolan模型的计算结果进行比较,表明所建立的疲劳损伤模型可以合理地预测零件的疲劳寿命。通过算例验证进一步证明了所提模型的准确性和可靠性。     

板带轧机工作辊裂纹应力强度因子的有限元求解方法

对于结构、受力及裂纹形态比较复杂的板带轧机轧辊,采用基于应力强度因子的判据是判断断裂的有效方法.为了克服轧辊裂纹应力强度因子计算的难题,提出了应力强度因子的间接计算方法.该方法结合了断裂力学的有关理论和有限元方法,可以灵活有效的进行各种载荷与裂纹形态的应力强度因子计算.通过对不同深度裂纹的应力强度因子计算,证明提出的方法有效.     

步进底式加热炉炉底结构有限元强度计算

运用有限元法对步进底式加热炉炉底结构进行强度分析,介绍了炉底结构的计算模型、边界约束和载荷处理,计算了炉底结构在4种载荷工况下的应力和变形。结果表明,炉底结构的总体强度和刚度能够满足设计要求。     

砖板衬里加压反应釜力学性能的有限元分析

本文介绍了砖板衬里加压釜的特点,分析了其工作状态下承载情况。针对一台湿法冶炼用加压釜,利用Ansys软件建立该设备筒体段的二维轴对称模型,计算了承受内压载荷与热载荷的情况下,筒体段的三向应力分布情况及变形量,并分析了计算结果。     

API偏梯形套管螺纹接头在上扣与轴向载荷下的有限元分析

针对深井和大位移井中套管存在很大轴向拉伸和压缩载荷的情况,对API偏梯螺纹接头进行有限元分析计算,得出了在不同载荷作用下螺纹接触应力的分布。     

煤岩配煤中CBI、SI参数的意义及其应用

在夏皮洛煤岩配煤技术中，CBI可判断配煤是否达到最佳点，SI表明煤中活性组分的强度。应用CBI、SI指标可以选择炼焦煤，确定最佳配煤比并预测焦炭强度。     

Using Assessment in Everyday Practice for the Benefit of Families and Practitioners.

How can assessments be more clinically useful and have more impact on a youth's long-term outcome? Assessments can outline a treatment approach in which target problems are linked to goals, client and family strengths, and specific treatment steps. This can be done in a comprehensive way, such that the youth's real-life functioning can be assessed across various domains. The initial assessment can serve as the baseline evaluation, with an expectation set for ongoing, periodic monitoring Parents can be encouraged to be actively involved in setting goals and in assessing their child's progress toward those goals. Outcome data can be aggregated across clients to generate practice-focused studies. These data can also be used to provide supportive evidence on behalf of local clinical programs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Animal models of neuromuscular diseases: pathophysiology and implications for rehabilitation

This article explains how animal models can be utilized to develop rehabilitation approaches to minimize the pathophysiology of neuromuscular diseases (NMD). Homologous animal models can be used to understand the pathogenesis of each NMD and the effect of physical interventions. Much of the current work using animals has been conducted to show how gene therapy could be used to ameliorate these diseases. Although we applaud this work, animal models should also be used to determine how the phenotypic expression of the disease can be modified by such physical interventions as exercise, stretching, and immobilization. Methods that can be experimentally applied to animals but not to humans can be used to determine the underlying causes of the pathologic process and to identify potential therapies for NMD.     

Thermodynamics of Modifying Effect of Rare Earth Oxide on Inclusions in Hardfacing Metal of Medium—High Carbon Steel

The modifying effect of rare earth(RE)oxide on inclusions in hardfacing metals of medium-high carbon steel was investigated by means of thermodynamics,The thermodynamic analsys for inclusion formation shows that RE oxide can be reduced to RE element by carbon,then the RE element can react with oxygen and sulfur to form the RE oxide,RE sulfide and RE oxide-sulfide in hardfacing molten pool.The deoxidization and the desulphurization can be carried otu and the liquid metal can be purified.In addition,RE oxide can also react with sulfur to form RE oxide-sulfide dirdctly.Therefore,the harmful effect of sulfur can be decreased.     

Optimal Structural Control Using Neural Networks

An optimal control algorithm using neural networks is proposed. The controller neural network is trained by a training rule developed to minimize cost function. Both the linear structure and the nonlinear structure can be controlled by the proposed neurocontroller. A bilinear hysteretic model is used to simulate nonlinear structural behavior. Three main advantages of the neurocontroller can be summarized as follows. First, it can control a structure with unknown dynamics. Second, it can easily be applied to nonlinear structural control. Third, external disturbances can be considered in the optimal control. Examples show that structural vibration can be controlled successfully.     

莱钢25t转炉提高出钢口寿命的实践

采用自流补炉料修补莱钢２５ｔ转炉出钢口,克服了原出钢口喷补料易被侵蚀而造成的出钢口寿命短、出钢时间不好控制等缺陷,使转炉出钢口寿命大大提高,出钢时间一般能控制在９０～１２０ｓ,降低了放钢温度,提高了转炉炉龄及其他经济技术指标。     

鞍钢180t转炉锥体氧枪的研制与应用

为解决氧枪结渣、粘钢难处理,氧枪寿命低问题,研制开发了锥体氧枪。生产实践表明,采用锥体氧枪,氧枪寿命平均可提高10%以上,枪体冷却效果能够满足吹炼要求,粘钢渣自行脱落效果好,粘钢渣容易处理,经济效益显著。     

The role of positron emission tomography in pharmacokinetic analysis

The physiological and biochemical measurements that can be performed noninvasively in humans with modern imaging techniques offer great promise for defining the precise state of a patient's disease and its response to therapy. In general, there are two critical points in drug development when PET measurements are likely to be particularly useful: (1) In preclinical studies, a new drug can be precisely compared to standard therapies or a series of analogs can be screened for further development on the basis of performance in appropriate animal models. (2) In phase I-II human studies, classic pharmacokinetic measurements can be coupled with imaging measurements (a) to define optimal dosing schedule; (b) to define the potential utility of interventions in particular clinical situations; and (c) to formulate the design of phase III studies that are crucial for drug licensure. In general, the types of measurements that are possible can be grouped into the following categories: 1. In those situations in which the drug can be radiolabeled, the time course of tissue delivery can be determined noninvasively in vivo in health and disease. Such information should be useful for determining dosing schedules, establishing efficacy, and predicting possible toxicity. 2. Ligand-receptor binding can be assessed in vivo in two ways. The ability of the drug to displace standard radiolabeled ligands from their receptors can be determined; alternatively, labeled drug can be used to more directly assess the distribution and time course of binding. These measurements are particularly useful for studying drugs that are active in the central nervous and cardiovascular systems. 3. Measurements of tissue metabolism will be useful in determining the effects of therapies aimed at particular metabolic abnormalities. In addition, these measurements may be useful in defining viability and function of tissues in such widely disparate clinical situations as cancer chemotherapy and cardiology. For example, effects of CNS or cardiovascular drugs can be monitored by observing 18FDG metabolism in brain and heart. We suggest that the joining of classic clinical pharmacology to exquisite imaging measurements will help form the basis for 21st-century clinical drug development.     

复合脱氧剂最佳成分的设计

为了保证钢液脱氧时产生低熔点、易碰撞长大的夹杂物，利于去除并防止因Al2O3生成时堵塞水口砖，同时使复合脱氧反应的自由能负值最大，保证易挥发元素损失最少且密度大，使钢液反应达到最佳的脱氧效果，根据相关资料计算出了最佳的复合脱氧剂组成。     

我国氧化铝技术发展方向

目前,我国氧化铝生产技术与国际先进水平之间的主要差距是生产能耗高、装备和自动控制水平较落后,未来我国氧化铝工来生产技术的发展方向是：混联法尽快过渡到并联法,尽可能降低烧结法比例,逐步过渡到串联法,双流法溶出工艺可以运用于生产中溶出一水硬铝石;管道化溶出工艺溶出一水硬铝石技术应尽快推广,大力研究开发生产氧化铝的新型装备及自动控制方法,尽快开发多品种氧化铝的生产。