Separation of phosphatidylcholine from soybean phospholipids by simulated moving bed

A simulated moving bed （SMB）, equipped with eight silica-gel columns, was used to separate phosphatidylcholine （PC） from soybean phospholipids. The effects of flow rate in Sections 2 （Q2） and 3 （Q3）, switching time, feed flow rate and feed concentration on the operating performance parameters： purity, recovery, productivity and desorbent consumption were studied. Operating conditions leading to more than 90% purity in both outlet streams have been identified, together with those achieving optimal performance. Regions leading to complete separation are observed and explained theoretically. As the mass-transfer effect was not considered, the triangle theory only gives initial guesses for the optimal operating conditions.     

情境与习作,相得益彰

习作中的情境教学,是指教师在指导学生动笔习作的过程中,根据习作内容、习作体裁的需要、结合作文指导课堂实际,创设生动活泼场景和轻松的学习氛围的教学,其丰富了学生的情感。情境与习作两者相辅相成,相得益彰,从而有效地提高学生的习作能力。     

基于模拟工况的电动汽车动力电池化成监测系统

针对常规电池化成方法的初期容量不合格、化成过度、效率低等不足,提出了基于模拟工况的电池化成新方法.系统采用模块化设计和网络控制技术,以单片机控制器为核心构成控制管理模块,在模拟实际工况的基础上,完成对电池化成过程的控制和管理;用AC/DC、DC/AC变换器实现能量的转换,完成对电池的充放电.运行结果表明,能够提高电池生产的效率和电池化成质量,延长电动汽车电池使用寿命和充电行驶里程.     

生物标本制作多媒体仿真实验课件的设计与开发

生物标本制作是高等教育生物学实验的重要组成部分,依据对标本制作实验教学的现状分析,在进行详细方案设计和充分准备工作之后,组织相关人员对实验进行了多媒体仿真课件的开发。文章完整论述了课件的设计和开发过程,以求与读者、同仁共同分享,并期望对不足之处给予指正。     

一种位场数据补充的插值法数学模型

指出位场函数具有变化梯度大等特点，与多项式函数的特性相差甚远，用拉格朗日插值法公式计算的插值精度低、可靠性差。当待插点离已知点较远时，几乎没有参考的价值。根据位场函数的特点，依据指数函数拟合位场函数导出指数函数拟合法插值公式。用这种插值公式内插补充和外推（包含向上和向下延拓计算）在理论模型上和在实际矿区上试算都证明了指数函数拟合法插值公式在位场数据补充上是一种精度比较高的插值数学模型。     

A comparison of the physiological response to simulated altitude exposure and r-HuEpo administration

Concerns have been raised about the morality of using simulated altitude facilities in an attempt to improve athletic performance. One assumption that has been influential in this debate is the belief that altitude houses simply mimic the physiological effects of illegal recombinant human erythropoietin (r-HuEpo) doping. To test the validity of this assumption, the haematological and physiological responses of 23 well-trained athletes exposed to a simulated altitude of 2650-3000 m for 11-23 nights were contrasted with those of healthy volunteers receiving a low dose (150 IU·kg^-1 per week) of r-HuEpo for 25 days. Serial blood samples were analysed for serum erythropoietin and percent reticulocytes; maximal oxygen uptake ([Vdot]O_2max) was assessed before and after r-HuEpo administration or simulated altitude exposure. The group mean increase in serum erythropoietin (422% for r-HuEpo vs 59% for simulated altitude), percent reticulocytes (89% vs 30%) and [Vdot]O_2max (6.6% vs -2.0%) indicated that simulated altitude did not induce the changes obtained with r-HuEpo administration. Based on the disparity of these responses, we conclude that simulated altitude facilities should not be considered unethical based solely on the tenet that they provide an alternative means of obtaining the benefits sought by illegal r-HuEpo doping.     

用模拟退火算法解决生产调度问题

介绍了Metropolis准则，给出了模拟退火算法解决生产调度问题的基本方法和步骤，并对算法的有效性进行了验证．     

Hybrid discrete particle swarm optimization algorithm for capacitated vehicle routing problem

INTRODUCTION The vehicle routing problem (VRP), which was first introduced by Dantzig and Ramser (1959), is a well-known combinatorial optimization problem in the field of service operations management and logis- tics. The capacitated vehicle routing problem (CVRP) is an NP-hard problem for simultaneously determining the routes for several vehicles from a central depot to a set of customers, and then return to the depot without exceeding the capacity constraints of each vehicle. In pr…     

Caprine cardiac sarcoplasmic reticulum: Effect of simulated ischemia on membrane structure and Ca<Superscript>2+</Superscript>-ATPase activity

The sarcoplasmic reticulum was isolated and characterized in the pure form from normal caprine (Capra hircus) hearts. Under ischemic condition, fatty acids like palmitic acid, palmitoyl carnitine and oleic acid accumulatein vivo. These are known to have a detrimental effect on membrane components. The effects of simulated ischemia on the Ca²⁺-ATPase were studied using these fatty acidsin vitro at concentrations at which they occurin vivo in the ischemic heart. All three fatty acids inhibited Ca²⁺-ATPase activity. At lower concentrations, palmitoyl carnitine was the most potent, followed by oleic acid while palmitic acid displayed the least potency. Electron microscopy studies with fatty acids showed morphological disruptions in SR vesicles. The decline in Ca²⁺-ATPase activity could be attributed to the change in membrane morphology.     

A New Capacitated Vehicle Routing Problem with Split Service for Minimizing Fleet Cost by Simulated Annealing

We address a capacitated vehicle routing problem (CVRP) in which the demand of a node can be split on several vehicles celled split services by assuming heterogeneous fixed fleet. The objective is to minimize the fleet cost and total distance traveled. The fleet cost is dependent on the number of vehicles used and the total unused capacity. In most practical cases, especially in urban transportation, several vehicles transiting on a demand point occurs. Thus, the split services can aid to minimize the number of used vehicles by maximizing the capacity utilization. This paper presents a mix-integer linear model of a CVRP with split services and heterogeneous fleet. This model is then solved by using a simulated annealing (SA) method. Our analysis suggests that the proposed model enables users to establish routes to serve all given customers using the minimum number of vehicles and maximum capacity. Our proposed method can also find very good solutions in a reasonable amount of time. To illustrate these solutions further, a number of test problems in small and large sizes are solved and computational results are reported in the paper.