碳酸化分解工艺的改进与实践

本文针对烧结法生产氧化铝过程中,铝酸钠溶液的碳酸化分解工艺,由间断分解到连续分解的改进进行了论述,指出连续分解是碳酸化分解的发展方向。     

两流薄板坯连铸连轧作业时铸坯在加热炉内的运行规律

讨论了两流薄板坯连铸连轧作业时铸坯在加热炉内的运动情况。分析了进入出坯段的铸坯的模式选择，进而确定铸坯进入平移段的时机。定义了加热炉综合进坯速度和加热炉平均出坯速度两个概念来讨论铸坯出坯的两种方案，并提出最小铸坯长度和最大加热炉综合进坯速度的计算公式。     

Until的用法以及与其他词的辨析

通过例句讲解了until的用法,辨析了until与till、before的异同,并列举了高中英语和大学英语部分课文及习题中的例句。     

普通碳素钢在CSP连轧过程中的组织演变

在CSP机组上，通过普通碳素钢(Q235)的轧卡试验研究了该钢在连轧过程中的组织演变过程。结果表明：高温区的两道次大变形使原始铸造树枝晶通过再结晶基本实现了奥氏体的等轴化和组织的均匀化；进一步变形可继续细化原始奥氏体并最终获得晶粒尺寸约为30μm的、均匀的等轴晶组织。在CSP工艺中，原始奥氏体组织细化可能与精轧总压下量高、单道次变形量大、应变速率高及钢中出现异常析出物等因素有关。     

酚醛树脂复合板在热连轧机中的应用

重点分析了现有F7机架出口导卫装置的情况。原导卫材料是由铸钢制造 ,由于摩擦和高温常常引起热连轧带钢表面划伤 ,根据现场实际情况用酚醛树脂复合板替代铸钢导卫装置。实践表明 ,这种改造即可行又可靠 ,并取得了好的效果     

连铸净化加压站改造

因攀钢动力厂连铸加压站的高压焦炉煤气供应不能满足生产需要，对它进行了相应改造。使工艺更加完善，煤气净化质量得到提高，并解决了生产中的一些问题。     

Influence of Billet Size on Flow, Solidification and Solute Transport in Continuous Casting

ListofSymbol　　B———Buoyancy ,m·s- 2 ;　　c———Concentrationofsoluteelement ;　　Cμ———Turbulentconstant;　　D———Diffusivityofsoluteelement ,m2 ·s- 1 ;　　fl,fs———Liquidandsolidfraction ;　　fμ———Turbulentcoefficient ;　　h———Enthalpy ,J·kg- 1 ;　　k———Turbulentkineticenergy ,m2 ·s- 2 ;　　kp———Equilibriumpartitioncoefficient;　　Kp———Permeabilityofmushyzone ,m2 ;　　K0 ———Permeabilitycoefficient;　　p———Pressure ,Pa ;　　Pr———Prandtlnumber ;…     

Analysis and Optimization of Noise in Bipolar RF Harmonic Mixers

A noise analysis of bipolar harmonic mixers (BHM) used for direct-conversion receivers is presented in this paper. Analytical and simulated results for the transfer function of the mixer are presented. Simple analytical expressions describing noise contribution from all sources are derived. Estimation of flicker noise quite agrees with harmonic-balance simulation results. Based on the derived expressions, total time average noise power spectral density (PSD) at the output is compared with simulation results. For the recommended regions of operation, error is less than 20%. The overall BHM noise figure (NF) is calculated and optimized based on a simple extracted formula. Errors introduced by analysis remain within a 1.5-dB margin with respect to simulation results. The validity of analysis for high frequencies is justified. The effect of flicker noise coefficient on the overall mixer NF is compared for different available processes.     

CALS及其在武器装备全寿命管理中的应用

简要介绍了连续采办与全寿命保障(continuous acquisition and life—cycle support，CALS)产生背景，着重研究了CALS的体系结构和关键技术，CALS对武器装备全寿命中各阶段的影响；对我国武器装备实施CALS战略的可能性进行了初步探讨；指出：CALS战略是21世纪武器装备全寿命管理的必然选择。     

Research and application of automatic control system of argon blowing at ladle shroud

Argon blowing at the ladle shroud requires the best flow control strategy to effectively avoid the secondary oxidation of molten steel, slag entrapment and heat loss during the casting of the tundish, and at the same time, give full play to the role of bubbles to remove inclusions. Therefore, an automatic control system for argon blowing at the ladle shroud was proposed. The data collected by S7-300PLC and software programming were used to adjust the argon blowing flow online in real time according to factors such as pouring and continuous pouring. On this basis, PID control algorithm and closed loop control mechanism were used for real time adjustment. The flow control valve ensures theminimum deviation between the actual value of the flow and the set value. The production data of this system in the first quarter of 2021 in a special steel plant show that the proportion of furnaces with an acid soluble aluminum (Als) loss percentage of less than 10% of each steel grade has increased by 5.52%, and the proportion of furnaces with an Als loss percentage of more than 60% has increased from 1% decrease to 0. The actual application results show that the use of the system improves the surface quality of the continuous casting slab and the performance of the final product.