Configurational statistics of copolymers prepared by complex-radical polymerization

Radical copolymerization is considered theoretically taking into account the effect of complexing on the configurational statistics of macromolecules formed. Akinetic model has been developed that considers, apart from the ordinary addition of single monomer units to a propagating chain, the possible addition of monomer unit pairs along with a complexing agent in the form of a ternary complex. Within the framework of this model, the problem of calculating the probabilities of formation of any sequences of monomer units (taking into account their microtacticity) in a macromolecule has been rigorously solved as well as the problem of finding the composition distribution of the copolymer formed. It has been shown that this distribution is described by a conventional Gauss law and the appropriate parameters are given. Possible generalizations of the suggested approach are indicated.     

电力供应链的收益风险研究

分析了电力供应链的特点,在对引入期权交易的售电商主导的电力供应链中,给出了期权定价市场化情况下实现电力供应链整体利润最优的期权价格组合和电量;在此基础上建立了综合考量电力供应链在多级市场的收益最大,同时占电力供应链主导地位的售电商风险最低的双目标规划的电量组合模型.算例表明电力供应链不同风险厌恶程度与收益给电量分配带来不同的影响,为电力供应链的电量组合与风险评估提供了新途径.     

Differences in two-dimensional gel electrophoresis patterns of skeletal muscle myosin light chain isoforms between Bos taurus, Sus scrofa and selected poultry species

BACKGROUND: In this study the interspecies differences in two‐dimensional electrophoresis patterns of skeletal muscle myosin light chain (MLC) isoforms between Bos taurus (cattle), Sus scrofa (pig), Gallus gallus (chicken), Meleagris gallopavo (turkey), Anas platyrhynchos (duck) and Anser anser (goose) were characterised on the basis of specific properties of MLCs associated with their structure and mobility in gel. RESULTS: Two‐dimensional electrophoresis separations revealed species‐specific differences in the molecular weight and pI of individual MLC isoforms (MLC1f, MLC2f and MLC3f). In the case of closely related animal species such as goose and duck or turkey and chicken, significant differences occurred in MLC1f. For MLC2f, differences between cattle and turkey and between pig and chicken were around 1 and 0.3 kDa respectively. It appeared from the comparison of amino acid sequences that even MLCs with only 2% difference in sequences have different electrophoretic mobilities. CONCLUSION: Interspecies differences in skeletal MLC isoforms appeared between cattle, pig, chicken, turkey, duck and goose. The slight changes observed in the course of the aging process confirmed that these proteins are relatively little susceptible to proteolytic enzymes during meat aging. Copyright © 2011 Society of Chemical Industry     

构件相似性识别的搜索矩阵法

构件的相似性识别是方案创新设计中避免同构方案的关键问题之一。基于图论中广度优先搜索算法,针对运动链再生创新设计中构件的相似性判断,提出了一种新的相似性判断方法——搜索矩阵法。首先根据邻接矩阵对运动链中某构件为树根进行广度优先搜索,产生赋权广度优先生成树,并将每层搜索到的构件运动副序列形成对应的广度优先搜索矩阵,然后根据两构件搜索矩阵是否相同来识别两构件是否相似。该方法具有操作简单、可靠性好、识别率高又易于计算机实现等特点。通过实例验证了这种方法的有效性和完备性。     

分布式库存管理系统仿真

为解决分布式库存系统中的库存控制问题,将调拨策略应用于一个二级供应链系统中,通过建立一个虚拟协调中心,提出了集中控制和分散管理的核心理念,将分散于各地分销点的库存信息进行集中管理,实现了库存信息的集成化。为避免解析方法的数学复杂性和不可控性,采用建模工具Anylogic进行了仿真,细分出33种策略,并分别分析比较其成本与服务水平,最后得出了适合于该系统的最优库存策略。     

A Pumpless Methanol Feeding Method for Application in Direct Methanol Fuel Cell Systems

This paper presents a simple and reliable pumpless methanol feeding (PLMF) method for application in direct methanol fuel cell (DMFC) systems. The primary feature and advantage of the PLMF is as follows: it employs an approach that allows the cathode gas pressure to be connected with a fuel container for supplying the methanol fuel into the anode fuel loop, instead of using any feeding pump or other specially designed apparatuses. The PLMF has been used in a portable 25 W DMFC system and realised feeding methanol in real time for meeting the requirements of the system. The PLMF method not only is suitable for the DMFC system, but also can be used in other liquid‐feeding fuel cell systems.     

Integration of enterprise levels based on an ontological framework

Enterprises are highly complex systems in which one or more organizations share a definite mission, goals and objectives to offer a product or service. In this study, an ontological framework is built as a mechanism for exchanging information and knowledge models for multiple applications and effective integration between hierarchical levels. The potential of the general semantic framework that is developed is demonstrated using a case study concerning the enterprise supply chain network design-planning problem.     

供应链结构分析

对供应链的结构研究进行了综述和特点分析,进一步提出了供应链的基本结构模型和基本决 策问题,并对基本结构模型进行了分析讨论,     

机构自由度计算问题的分析研究

提出了现有《机械原理》教材中机构自由度计算公式中存在的一些值得研究和改进的问题,在此基础上,重点论述了机构自由度计算方法,提出了一个具有普遍意义的,对各种机构自由度计算问题都适用的公式,从而基本解决了各种机构自由度计算问题和用不同方法计算同一种机构的自由度其结果不同的问题。     

微型燃气轮机在分布式供电系统中的应用

本文通过对微型燃气轮机技术特点分析，指出了其在分布式供电系统中的主要应用方式。