Present state of corrosion inhibitors in Japan

In this report, the utilization, research and development of corrosion inhibitors in Japan and the action mechanism of corrosion inhibitors are explained, and their effects and future utilization are also described. In Japan, corrosion inhibitor was commercialized in the 1970s, and the use of these showed the rapid elongation as a countermeasure of the use of sea sand as an aggregate for the period 1975–1977 and the use of corrosion inhibitors decreased after 1979 because of the regulation for the total amounts of chloride in concrete in the standards. Then, amounts of concretes with corrosion inhibitors decreased in 1990s. However, in the civil engineering and construction industry fields, they seem to have to deal with the problem of increase of chloride content in concrete by the deregulation and the utilization of various industrial waste materials. We should consider the utilization of corrosion inhibitor from the new viewpoint.     

惯性导航设备升沉数据测试系统研究

研制了一套基于STM32单片机与单轴摇摆台的测试系统,利用固定圆心、固定半径条件下的圆内三角形关系,通过拉线传感器采集单轴摇摆台复合运动中的升沉数据;同时,对惯性导航设备输出的升沉数据进行采集与处理。对测试系统输出的升沉数据进行了验证,实验结果表明:该测试系统的测试数据准确合理,可实现对惯性导航设备升沉参数的动态测试,弥补了现有同类测试系统的结构复杂、量程小等不足。     

Optimal Design and Economic Evaluation of Dividing‐Wall Columns

In an effort to reduce costs, a systematic optimization approach is proposed to address the energy consumption of dividing‐wall columns (DWCs). This iterative optimization procedure begins by minimizing the overall heat duty using an innovative objective function within a constrained design space. A sensitivity analysis is then carried out on the manipulated variables to obtain their optimal ranges. Optimal operating parameters are obtained through the evaluation of the total annualized cost (TAC). For the separation process of benzene/toluene/o‐xylene, the optimal DWC flow sheet exhibits a significant decrease in TAC when compared to conventional flow sheet optimum designs. The applied optimization method and sensitivity analysis have proven to produce results at the global optimum. This method is both practical and easily applied to other systems, even to systems with more than three components.     

Knowledge-enhanced graph convolutional network for recommendation

Multimedia Tools and Applications - Recommendation systems based on collaborative filtering (CF) are often accompanied by cold start and sparsity issues, which can be alleviated by using user...     

LX200摩托车车架有限元分析及强度评价

综合运用CATIA、MSC.PATRAN等软件,结合摩托车车架结构特点和实际承载情况,建立了LX200摩托车车架有限元计算分析模型;通过模型检查,验证了模型的可行性和有效性;在此基础上对车架进行了有限元分析,并根据计算结果对车架进行了强度评价.结果表明,LX200摩托车车架设计较保守,具有较大的轻量化设计空间.     

基于三维激光扫描的倾斜圆面直径测量系统

针对倾斜圆面的空间几何特征,提出将三维激光扫描技术与虚拟环境 引导定位结合的快速圆面直径测量系统。该系 统通过圆面边缘端点来约束移动激光扫描仪的扫描视角与深度,并在虚拟环境下实时跟随扫 描仪轨迹构建虚拟测量基准面, 进而参考已标识的端点与基准面相对位移变化,来逐步规划扫描仪的轴向运动路径,以此实 现边缘轮廓的自动高质量采样; 依据高度特征变化识别定位圆面边缘端点,并结合空间投影和最小二乘原理拟合出圆面直径 。为验证系统的精度和可靠性, 对处于不同倾斜状态的圆台工件(55±5mm)进行直径检测。结果显 示,系统可在3s内完成直径测量,检测分辨率为5μm、 检测精度为20μm。实际运行结果表明,该设计系统具有高自动性和 高效性,能很好满足在线生产中对倾斜圆面直径的检测要求。     

Development of in situ a.c. impedance measurement system under constant-current conditions and its application to galvanostatic discharge of electrolytic manganese dioxide in alkaline solution

An inexpensive a.c. impedance measurement system to elucidate the solid-phase electrochemical reactions inside the active materials of batteries during charge and discharge has been developed by using a cheap galvanostat and a personal computer. In order to develop a simple, in situ, a.c. impedance measurement system for evaluating cells, the impedance of manganese dioxide in alkaline solution under constant-current discharge has been measured. To obtain the impedance, a discrete sinusoidal current is superimposed on the cell under the constant-current polarization, and the resulting transfer function is calculated by a single, sine wave, correlation method. Software developed in this study makes it possible to measure the impedance without using a frequency-response analyzer. A large sinusoidal current of magnitude up to that of the discharge current can be superimposed while keeping the sinusoidal potential response in the linear range, and this enables reliable impedance measurements to be conducted. The impedance and frequency characteristics thus obtained reflect well the discharge behaviour of manganese dioxide in alkaline solution.     

乙酸乙酯萃取进样-电感耦合等离子体原子 发射光谱法测定矿石中金

为了提高分析效率和降低分析成本,保证分析人员的身体健康,选择一种分析时间较短、试剂毒性较小、易操作的矿石中金测定方法尤为重要。样品采用王水溶解后,在分液漏斗中,选择试剂毒性较小、价格便宜的乙酸乙酯定量萃取,萃取液直接导入配备有机进样系统的电感耦合等离子体原子发射光谱仪(ICP-AES),选择Au I 242.795nm为分析谱线,对矿石中金进行测定,从而建立了电感耦合等离子体原子发射光谱法(ICP-AES)测定矿石中金的方法。采用萃取分离法消除基体元素及共存元素的干扰。通过对萃取酸度、萃取剂、萃取方法、仪器工作条件、分析谱线等条件试验,确定了最优的实验条件。金的质量浓度在0.10~16.00mg/L范围内与其发射强度呈线性,校准曲线线性相关系数为0.9998。金检出限为0.02mg/L。按照实验方法测定5个矿石金标准物质中金,测定结果的相对标准偏差(RSD,n=10)小于3%;测定值和认定值比较吻合。方法可用于金质量分数在0.25~38.0g/t之间的矿样检测,单个样品的检测时间约4h,可用于批量检测。     

Be/HR-1不锈钢扩散连接界面附近的元素扩散

为了优化热静压扩散连接工艺参数,应用有限元法对Be/HR-1不锈钢扩散连接界面附近铁和铍元素的分布进行了计算机模拟,并通过俄歇电子能谱(AES)进行实验测定。结合计算机模拟结果和实验数据探讨了扩散连接界面附近铁和铍元素的分布、扩散宽度与温度、压力和时间的关系。结果表明:在1050℃/60 MPa/2 h和750℃/60 MPa/2 h热静压下,扩散连接界面附近Be,Fe元素分布的实测数据与计算机模拟结果基本吻合;在60 MPa/2 h热静压下,加热温度分别为1050和750℃时对扩散宽度影响的实测数据与计算机模拟结果基本吻合,1050℃时的扩散宽度是750℃时的2.5倍;在750℃/2 h热静压下,压力分别为30,40,50,60 MPa时对扩散宽度影响的实测数据与计算机模拟结果基本吻合,扩散宽度与压力成抛物线关系;在750℃/60 MPa热静压下,扩散宽度与扩散时间的模拟曲线也成抛物线关系。     

食醋的氧化值测定及其应用探讨

根据酿造食醋与配制食醋挥发性组分含量的差异,提出了一种测定食醋中挥发性还原性组分的方法,即氧化值法,并将氧化值定义为100mL食醋样品蒸馏液所消耗的0.002mol/L KMnO4的体积(mL)数。经过分析发现,酿造食醋与配制食醋、冰乙酸的氧化值存在显著性差异。结果提示食醋的氧化值可在一定程度上反映其酿造属性,可作为反映食醋样品品质的一个指标,并有可能通过测定氧化值来判断某一食醋是否为酿造食醋。所建立的食醋氧化值测定法具有操作简便、重复性好的特点,具有较大的推广应用价值。