Design of a fully thermally coupled distillation column based on dynamic simulations

A dynamic simulation of a fully thermally coupled distillation column is conducted for the design of a possible operation scheme, and its performance is examined with an example process of butanol isomer ternary system. The outcome of the dynamic simulation indicates that the column can be operated by using a 3 × 3 control structure. The structure consists of three controlled variables of the compositions of overhead, bottom and side products and three manipulated variables of the flow rates of reflux and steam and liquid split ratio between a main column and a prefractionator. This paper was presented at The 5th International Symposium on Separation Technology-Korea and Japan held at Seoul between August 19 and 21, 1999.     

动态图像法在果粒饮料粒度分析中的应用

目的提高果粒饮料的质量监控,改进产品配方,提升饮料的口感。方法采用动态图像法对果粒样品的最大FERET直径进行分析,建立一个粒度粒形与果粒型橙汁饮料口感的关系。结果最大FERET直径大于9 mm的颗粒基本为原始橙粒果肉原料,适当增加该成分对口感的提升有极大帮助。结论对于果粒饮料,动态图像分析法可以给出果粒的原始图形信息,且统计量大,代表性强,对其配方改进及生产质控具有密切的指导意义。     

织物动态悬垂性的研究

以旋转悬垂体来表现织物动态悬垂性为依据,设计了相应的测试系统。结合理论对悬垂体受力情况的分析,作了试验结果的形态和物理两方面的解释。     

Optimal operating conditions calculation for a pork meat dehydration-impregnation-soaking process

Mass yield and operating time for a pork meat dehydration-impregnation-soaking (DIS) process were optimized using a coupled genetic algorithm/sequential quadratic programming method in order to obtain the optimal operating conditions: temperature and soaking solution concentrations. The DIS process was simulated by a neural network model. The non-linear optimization problem was constrained to ensure the main product characteristics: stability indicated by the water activity target and flavour characterized by the phenol gain target. The climatic conditions, the model validity region, the raw material costs and the operator working schedule were taken into account.Optimal solutions are discussed for three different batch configurations: single-stage processing under constant conditions, single-stage processing under varying temperature and two-stage processing under constant conditions. The most convenient operation resulted in a two-stage soaking process because of time, energy and cost savings, control convenience, product cooling anticipation and a reasonably high mass yield.     

Research on the Characteristics of Hot Deformation in BT20 Titanium alloy and Its Optimum Spinning Temperature Range

Hot compression tests were conducted on a Gleeble-1500 simulator to investigate the hot deformation behavior of BT20 Ti alloy (Ti-6Al-2Zr-1Mo-1V) in the temperature range from 550 to 1000℃ at constant strain rate in the range of 0.01～1 s-1, and then the optimum spinning temperature range was determined. Moreover, tube spinning experiments were executed to verify the reasonability of the optimum temperature range. The results show that the flow stress declines gradually with increasing deformation temperature and decreasing strain rate. In α β phase region the dynamic recrystallization is the main softening mechanism and in β phase region the hot deformation softening is controlled by dynamic recovery. In α βphase region with reducing strain rate dynamic recrystallization is fully developed. The optimum temperature of hot spinning is 850～900℃ and that of warm spinning is 600～650℃.Meanwhile, at the temperature above 600℃ tubular workpieces of BT20 Ti alloy have been spun without surface cracks and microstructure inhomogeneity, which proves that the optimum spinning temperature range obtained through hot compression experiments is reasonable.     

Primary Recrystallization of Grain Oriented Silicon Steel Strip Rolled by CSR and Annealed in Magnetic Field

The magnetic properties and textures of grain oriented silicon steel with different thickness rolled by cross shear rolling (CSR) of different mismatched speed ratio (MSR) and annealed in magnetic field under hydrogen were presented. Effects of the factors such as thickness and mismatched speed ratio on the magnetic properties and recrystallization texture were analyzed and the recrystallization principles in magnetic field annealing were discussed. The study would provide a new route for mass production of high quality ultra-thin grain oriented silicon steel strip.     

Superplasticity Enhanced by Two-stage Deformation in a Hot-extruded AZ61 Magnesium Alloy

A two-stage strain rate deformation method is proposed to enhance the superplasticity in a hot extruded AZ61 alloy. In the stage-one of deformation, a relatively high strain rate was applied in order to obtain fine grains through dynamic recrystallization. The optimum strain rate for DRX at 300℃ was identified as -5×10-3s-1. Stage-two is conducted at relatively low strain rate in order to utilize the fine grains refined by DRX during stage-one to make the grain boundary sliding operate more smoothly, which resulting in enhanced superplastic elongation from 350% to 440%.     

一种通用中间件连接件的设计与实现

设计了一种为可视化开发工具与多个中间件系统之间提供无缝接口的统一连接件,介绍了其基本结构和主要实现方法,并给出了具体应用。     

基于BP网络的超声波动态液位监测

液体在运输过程中会产生明显的晃动,其液位的实时动态监测一直是一个技术难题,至今没有得到很好的解决。本研究以此为突破口,采用三个超声波传感器组成阵列结构,同步激励发射脉冲超声波,利用定长时窗内接收的回波信号包络提取瞬时液面反射点的时延信息,再结合三点瞬态液位平均值与液体晃动梯度等参数,训练BP神经网络,得到动态液位的数学模型。在实验室条件下的试验结果表明,该方法可准确测得液体在模拟运输过程中的液位。这项技术也可以用于测量其静态液位。在石油化工、冶金、电力、制药等行业有着广阔的应用前景。     

动态散斑对比度颗粒测量法

提出了基于线阵CCD相机的动态散斑对比度颗粒测量方法和系统,用于解决动态光散射研究涉及的动态光散射软件相关算法运算量大、实时性较差,以及不能测量高黏度溶液中颗粒的问题。首先,从传统动态光散射理论出发,基于光学统计理论,建立了动态散斑对比度的模型。然后,根据Siegert公式,推导了动态散斑对比度与动态散射光场自相关函数的关系。最后,得到了低浓度和高浓度下动态散斑对比度与颗粒粒径的关系。分别对粒径分布为(490±20)nm的标准乳胶球颗粒水溶液和纳米二氧化钛粉体(粒径分布:450~500nm)甘油溶液进行了测量。结果表明:动态散斑对比度测量法的运算量小,且能测量高黏度溶液中的纳米颗粒,重复测量误差小于2%,满足了动态光散射的国标要求。