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在脱磷理论分析基础上,采用低枪位冶炼和低终点氧出钢,增大出钢口直径和降低终点温度,并优化底吹工艺降低碳氧积,取得了较好的脱磷效果。生产应用结果表明:采用增大出钢口和优化底吹工艺后,300t转炉出钢时间缩短至5.1 min,缩短了1.9 min;IF钢终点温度降低至1 670.6℃,降低了17.4℃;碳氧积降低至13.3,降低了8.9;终点氧降低至422.5×10-6。在铁水磷升高0.010%,枪位降低30 cm,终点氧降低153.3×10-6的条件下,工艺优化后的平均终点磷含量为0.012 4%,能够满足转炉冶炼IF钢对脱磷效果的要求。 相似文献
3.
基于确定性微分博弈理论,建立了一种庄家与散户间的连续时间的博弈模型.首先将所有散户作为一个整体与庄家进行博弈,以博弈双方持股率的动态关系作为动态系统方程,并以此构建了一个确定性微分博弈模型; 然后运用开环纳什均衡和反馈纳什均衡分别求解出满足共态函数的常微分方程组和满足价值函数的Issacs - Bellman偏微分方程,以此得到庄家与散户博弈的开环纳什均衡策略和反馈纳什均衡策略.该结果可为金融监管部门监管证券市场和证券市场投资者买卖股票提供参考. 相似文献
4.
The effect of aluminum on the treatment of fluorine-containing synthetic wastewater by crystallization was investigated. The results showed that the optimal conditions for fluoride removal were found at pH 7.2–10.5, and at an aluminum concentration of 80–700 mg/L. During operation of the fluidized bed reactor, the effluent fluoride concentration was 13–25 mg/L at an influent aluminum concentration of 80–150 mg/L. The recovered pellets matched well with the national standard of fluorspar in China (GB19321-88). It was feasible to recover calcium fluoride from fluorine and aluminum-containing wastewater by crystallization. 相似文献
5.
The electrochemical behavior of lanthanide elements deposited on liquid zinc cathodes was studied using cyclic voltammetry (CV) and open circuit chronopotentiometry (OCP). We observed a "bimodal effect" in the equilibrium deposition potentials of zinc with lanthanides. A mathematic equation is derived to illustrate the relationship between the equilibrium potential of the intermetallic compounds formed by lanthanide elements and zinc and their atomic radius. This equation is not only applicable to lanthanide elements but also hold for other elements such as alkali metal lithium, alkaline earth metal magnesium, calcium and transition metal niobium, which have crucial theoretical significance for the electrolysis of intermetallic compounds, the separation, and extraction of metals. 相似文献
6.
传统边坡地震稳定性分析方法鲜有考虑土体拉裂破坏引起的张裂缝。基于极限平衡-拟静力法建立了水平地震力和竖向地震力作用下的力与力矩平衡方程,运用变分理论获得其临界破坏面及其对应的正应力分布,考虑土体没有抗拉强度建立考虑张裂缝的地震边坡屈服加速度的闭合解答。张裂缝的出现会显著降低地震边坡的稳定性,对于垂直边坡将达到50%。当边坡坡度较大时,竖向地震力向下作用获得的屈服加速度更小,当边坡坡度较小时,竖向地震力向上作用获得的屈服加速度更小。 相似文献
7.
Most of the existing stochastic games are based on the assumption of complete information,which are not consistent with the fact of network attack and defense.Aiming at this problem,the uncertainty of the attacker’s revenue was transformed to the uncertainty of the attacker type,and then a stochastic game model with incomplete information was constructed.The probability of network state transition is difficult to determine,which makes it impossible to determine the parameter needed to solve the equilibrium.Aiming at this problem,the Q-learning was introduced into stochastic game,which allowed defender to get the relevant parameter by learning in network attack and defense and to solve Bayesian Nash equilibrium.Based on the above,a defense decision algorithm that could learn online was designed.The simulation experiment proves the effectiveness of the proposed method. 相似文献
8.
《International Journal of Hydrogen Energy》2020,45(7):4673-4684
The aim of this work is to experimentally study, the behavior of a metal-hydrogen reactor (MHR) subjected to the action of an external magnetostatic field, during hydrogen absorption and desorption by the LaNi5 hydride. The reactor was surrounded by a copper coil crossed by a continuous current delivered by a DC generator. In this study, the mass of the absorbed and desorbed hydrogen was measured and plotted for different initial temperatures and pressures functions of the applied magnetostatic field. The ratio of the hydrogen mass absorbed or desorbed with and without supplying a magnetostatic field was estimated after which the change in the saturation magnetization per 1 mol of desorbed hydrogen atom (ΔMs), for the LaNi5 compound; was determined.The results demonstrated that while the increase in temperature was not beneficial for the absorption reaction, it improved the desorption process. The increase in pressure leads to an increase in the absorbed hydrogen mass. The effect of the applied magnetostatic field was observed especially for the lowest temperatures in the case of the absorption reaction. In fact, we noticed a small increase in the absorbed mass, which decreased and disappeared in the highest temperatures. It was found that the magnetostatic field had no effect on the desorption reaction for the tested fields and temperatures. The low value of ΔMs confirmed the paramagnetic nature of the sample. 相似文献
9.
《Ceramics International》2020,46(2):1545-1550
Ti-bearing blast furnace slags have been regarded as an important secondary material in modern society, and the efficient recycling of Ti oxides from it is of key interest. For this reason, more thermodynamic data is needed regarding the phase relations in different composition ranges and sections. Therefore, the equilibrium phase relations of CaO–MgO–SiO2–Al2O3–TiO2 system in a low w(CaO)/w(SiO2) ratio of 0.6–0.8 at 1250 °C in air and fixed concentrations of MgO and Al2O3, were investigated experimentally using a high temperature equilibration and quenching method followed by SEM-EDS (Scanning Electron Microscope and Energy Dispersive X-ray Spectrometer) analyses. The equilibrium solid phases of perovskite (CaO·TiO2), a pseudo-brookite solid solution (MgO·2TiO2, Al2O3·TiO2)ss, and anorthite (CaO·Al2O3·2SiO2) were found to coexist with the liquid phase at 1250 °C. The calculated results of Factsage and MTDATA were used for comparisons, and significant discrepancies were found between predictions and the experimental results. The 1250 °C isotherm has been constructed and projected on the CaO–SiO2–TiO2-8 wt.% MgO-14 wt% Al2O3 quasi-ternary plane of the phase diagram. The obtained results provide new fundamental data for Ti-bearing slag recycling processes, and they add new experimental features for thermodynamic modeling of the high-order titanium oxide-containing systems. 相似文献
10.
《Thin》2015
The paper is devoted to buckling and post-buckling problems of an elastic seven-layered cylindrical shell under uniformly distributed pressure. The shell is an untypical sandwich structure composed of main corrugated core and two three-layer faces. Numerical FEM model for the shell has been elaborated. The calculations have been performed with the use of the ANSYS code for elastic shells of different dimensions. The linear and non-linear analyses of the shells have been performed with the use of the finite elements method. Critical pressure and equilibrium paths for the family of seven-layered shells subjected to uniformly distributed external pressure are calculated. The influence of corrugation pitch of main core and the length of the shell on the critical pressure has been determined. The results of these investigations are presented on the graphs. 相似文献