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41.
STUDY ON SLAG DETACHABILITY AND STICK SLAG MECHANISM OF SSFCE   总被引:4,自引:0,他引:4  
研究了熔渣的线胀系数和碱度对自保护药芯焊丝脱渣性的影响规律,借助金相学原理建立了预测碱性自保护药芯焊丝脱渣性的经验公式,并对其粘渣机理进行了分析.  相似文献   
42.
本文采用火用分析法 ,对冷轧带钢的罩式炉热处理系统进行了能量分析 ,计算了热处理过程中的各种火用值、热量及系统火用效率 ,指出了系统用薄弱环节 ,并分析了用能薄弱环了的火用损失分布情况。分析结果为工艺用能改造提供了依据。  相似文献   
43.
新型的电弧炉电极微机控制系统   总被引:2,自引:0,他引:2  
本文介绍了一种新型的电弧炉电极的微机控制系统,重点论述了计算机硬件和软件开发及其安装调试要点.  相似文献   
44.
本文通过对玻璃熔窑结构的分析以及国内外部分厂的实践,提出降低燃料消耗的途径。  相似文献   
45.
In the past, blast-resistant designs for structures were often constructed with massive type structural systems, which relied more on brute strength than on finesse to achieve the required blast resistance. However, structures composed of COLD-FORMED steel components, such as sheet metal and metal studs, have shown great promise in providing blast resistance with the added benefits of low cost and ease of construction. Some examples of using such structures to provide containment for package handling facilities (PHF) are described in the paper for situations where blast containment is needed, such as a potential package bomb being discovered during the package vetting process. Results from tests and analytic data are used to illustrate aspects of design peculiar to such types of applications. Designs for specific capacities of PHF are described.  相似文献   
46.
石墨炉原子吸收法测定茶叶中的镍   总被引:3,自引:0,他引:3  
采用硝酸为介质 ,使用自吸背景校正法 ,测定不同茶叶中的痕量镍并对不同处理方法的结果进行了比较 .该法在 2 0— 40 0 μg/L范围呈良好的线性关系 ,特征量为 4.4× 10 - 1 0 g .  相似文献   
47.
Dynamic responses of a multi-storey building without or with a sliding base-isolation device for ground shock induced by an in-tunnel explosion are numerically analyzed. The effect of an adjacent tunnel in between the building and the explosion tunnel, which affects ground shock propagation , is considered in the analysis. Different modeling methods, such as the eight-node equal-parametric finite element and mass-lumped system, are used to establish the coupling model consisting of the two adjacent tunnels, the surrounding soil medium with the Lysmer viscous boundary condition, and the multi-storey building with or without the sliding base-isolation device. In numerical calculations , a continuous friction model, which is different from the traditional Coulomb friction model, is adopted to improve the computational efficiency and reduce the accumulated errors. Some example analyses are subsequently performed to study the response characteristics of the building and the sliding base-isolation device to ground shock. The effect of the adjacent tunnel in between the building and the explosion tunnel on the ground shock wave propagation is also investigated. The final conclusions based on the numerical results will provide some guidance in engineering practice.  相似文献   
48.
Two numerical simulations were performed to investigate the protective effect of the foam cladding. One simulation is based on a previous experimental study, which is a ballistic pendulum with and without a foam cladding subjected to close-range blast loading. The other model is a steel beam with and without a foam cladding under blast loading. The overpressure due to the blast event can be calculated by the empirical function ConWep or by an arbitrary Lagrangian-Eulerian (ALE) coupling model. The first approach is relatively simple and widely used. The second approach can model the propagation of the blast wave in the air and the interaction between the air and the solid. It is found that the pendulum with the foam cladding always swings to a larger rotation angel compared to a bare pendulum. However, the steel beam with an appropriate foam cladding has a smaller deflection compared to the bare beam without a foam cladding. It is concluded that the protective effect of the foam cladding depends on the properties of the foam and the protected structure.  相似文献   
49.
应用有限单元法对模块式炉身温度场进行区域离散,对乌克兰大型模块式炉身各截面在不同边界条件下的二维温度场分布进行了计算,得到各特征截面二维温度场分布图。证明模块式炉身温度场分布合理,其利用渣皮工作的原理是可行的;论证了乌克兰设计中冷却水管间距、冷却水流速、管径及水温取值的依据。  相似文献   
50.
本钢铁业公司1#高炉近几年通过采取多种措施使高炉生产逐日强化,并在不断强化冶炼的基础上保持高炉稳定、顺行。本文论述了强化的技术措施,取得的效果,并提出进一步强化冶炼的发展方向。  相似文献   
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