THERMODYNAMICS ON THE SELECTIVE OXIDATION OF ELEMENTS IN MOLTEN MATTE AND METALS

总结讨论了熔锍及熔融金属中元素选择性氧化的行为,举出镍锍中 Ni 与 S,铁液中 Cr,V,Nb,Mn 或 P 与 C 作为应用的实例.利用热力学分析提出氧化的转化温度的概念,并指出二步及一步计算该温度的方法.在排除新相生成的晶核能的条件下,氧化的转化温度与氧的存在形式(无论是气态 O_2,溶于金属液中的[O]或炉渣中的 FeO)以及氧的压力或活度无关,而只决定于参加反应的物质及产物的本质及活度(压力).同时,转化温度不是一成不变的温度,而是随着熔池组成的改变而不断地在变化.降低气体氧化产物的分压将有助于降低氧化的转化温度.理论计算的转化温度可提供使熔池中一个元素的优先氧化而使另一元素保留不变的最佳条件.小型实验和工业上实践证明,转化温度的概念可以成功地控制吹炼操作,作到按意图进行选择性氧化.影响熔池内元素氧化顺序的动力学因素也作了简略的分析.对镍锍脱 S、不锈钢脱 C 以及高碳锰铁降 C 的吹炼,熔池温度永远要高于相应熔池组成的转化温度.而对铁水脱 Cr 和铁水提 V 或 Nb,熔池温度则应保持低于相应熔池组成的转化温度.P,C 在铁水中的氧化顺序,除与转化温度有关外,还取决于熔渣组成以及 CO 承担的压力.     

基于多特征与DCNN的红外SF6泄漏检测方法研究

传统SF6泄漏检测耗费大量人力物力.针对该问题,提出一种基于红外成像技术的自动检漏方法.使用混合高斯模型确认泄漏视频中的疑似泄漏区域;通过HSV颜色空间分析SF6泄漏的颜色特征;分析泄漏SF6在红外技术下的动态特性,提取其不规则运动特征;使用膨胀卷积神经网络(DCNN)作为分类器,并在视频帧上完成对泄漏区域的标注.实验结果表明,该方法通过检测不同设备、不同部位的SF6泄漏视频能够准确标记出SF6泄漏区域,检测准确率可以达到82.71％.     

Nb_2O_5-MnO-SiO_2渣中Nb_2O_5和MnO活度的研究SCIEI

本文利用含NbFe液与Nb_2O_5-MnO-SiO_2渣之间平衡,在1828K温度下应用固体电解质浓差电池方法测定了Fe液中氧的活度,从而计算出渣中Nb_2O_5及MnO的活度,并绘制了Nb_2O_5-MnO-SiO_2三元系的等α_(Nb_2O_5)和等α_(MnO)图。     

SOLUBILITY OF Ca IN Mn AND INTERACTION COEFFICIENTS OF Al AND Fe ON Ca IN Mn AT 1350℃

本文测定了1350℃时液态金属Ca在纯Mn液中和Mn合金溶液中的溶解度,并计算出Mn液中Al及Fe对Ca的活度相互作用系数。实验结果表明Al对Ca有很强的相互作用,使Ca的溶解度增加,而Fe却使Ca的溶解度下降。本文还就液态Ca溶于Mn液的标准溶解自由能进行了估算。     

Force Control of Electro-Hydraulic Servo System Based on Load Velocity Compensation

In an electro-hydraulic servo control system, the force servo system is an important component. However, due to the nonlinear characteristic of hydraulic systems, traditional control methods cannot achieve satisfactory control performances. To deal with this issue, a load velocity compensation algorithm based on the structural invariant principle is proposed in this paper. First, the theoretical analysis of the hydraulic and cylindrical force control system is presented, and the mathematical model of the force control system is established. Then the open-loop frequency response characteristics of the system are analyzed, in which the Bode diagram shows that the bandwidth of the system is obviously expanded after adopting the load velocity compensation algorithm. Finally, a practical hydraulic and cylindrical force servo system is introduced to validate the feasibility of the proposed controller, the experimental results demonstrate that the proposed method can improve the performance of force control and eliminate the influence of load stiffness on the dynamic characteristics of the system through a set of comparative experiments with different elastic loads.     

Ca在金属Mn中的溶解度及Al,Fe对Mn溶液中Ca的活度系数的影响

本文测定了1350℃时液态金属Ca在纯Mn液中和Mn合金溶液中的溶解度,并计算出Mn液中Al及Fe对Ca的活度相互作用系数。实验结果表明Al对Ca有很强的相互作用,使Ca的溶解度增加,而Fe却使Ca的溶解度下降。本文还就液态Ca溶于Mn液的标准溶解自由能进行了估算。     

预应力高强混凝土管桩的施工实例

本文介绍澳门运动场扩建及改造工程的超深预应力高强混凝土管桩施工的应用实例。     

Investigation of optical and electronic properties in Al–Sn co-doped ZnO thin films

Al-Sn co-doped ZnO thin films were deposited onto quartz substrates by sol-gel processing. The surface morphology and electrical and optical properties were investigated at different annealing temperatures. The surface morphology showed a closely packed arrangement of crystallites in all the doped films. As prepared co-doped films show a preferred orientation along an (0 0 2) plane. This preferred orientation was enhanced by increasing the annealing temperature to between 400 °C and 500 °C, but there was a shift to the (1 0 1) plane when the annealing temperature rose above 500 °C. These samples show, on average, 91.2% optical transmittance in the visible range. In this study, the optical band gap of all the doped films was broadened compared with pure ZnO, regardless of the different annealing temperature. The carrier concentration and carrier mobility of the thin films were also investigated.     

基于SEF-GHEI及协同表示的步态识别研究

将协同表示方法应用于步态识别中可以解决稀疏表示方法计算耗时的问题,但提取步态特征采用的GEI算法没有考虑步态内部轮廓边界信息,导致识别率不高。针对此问题,本文提出使用融合Hog和GEI算法的方法提取步态特征,在此基础上使用协同表示的方法训练,再通过计算测试样本的最小重构误差进行分类。实验结果表明,该方法在单一视角下步态识别准确率平均提高了1.315%,以及跨视角下步态识别准确率平均提高了6.51%,说明本方法是可行的。