二垩英与资源回收-Ⅰ考虑到二垩英生成的资源与能量回收基础研究

目前在日本,存在大量工业垃圾,包括各种塑料制品,ASR(汽车破碎垃圾),含有毒PCB(多氯联苯)的110变压器和PVC(聚氯乙稀)制品等.而来自城市垃圾焚烧炉的废气含有大量能量.因此,在充分考虑环境、避免二垩英生成的同时,安全回收来自工业垃圾、城市和/或工业垃圾焚烧炉的资源和能量是个非常重要的课题,这也将对抑制CO2排放作出贡献.正确地阐明焚烧过程中二垩英的生成机理及详细研究含少量二垩英的焚烧废气在冷却过程中大量形成二垩英的临界温度是项很重要的工作.解决这个问题可有效实现资源和能量的回收.本报告介绍日本在二垩英排放方面目前采取的对策和存在的问题以及大阪大学为阻止二垩英生成所做的基础研究工作.     

基于同时发射声纳环移动机器人导航系统

开发了一种能在未知环境下实现快速障碍检测与障碍回避的基于同时发射声纳环移动机器人导航系统。为了消除由于同时发射造成的串话干扰,提出了一种基于神经网络模式识别的过滤方法;并制作了由24个声纳传感器组成的声纳环安装到实际的移动机器人上,实现了扫描频率最大可达到66 Hz的全景检测。系统中应用了动态窗口法来完成快速障碍回避的运动规划。实际的导航实验表明,系统可用于室内未知环境中的移动机器人快速导航。     

Reversible Molecular Rearrangement of Slightly Acid-treated Starches

The reersible association and dissociation of starch chain populations obtained from acid-treated starches (ATSs) was investigated. Potato starch, both nonglutinous and glutinous rice starches and sago starch were suspended in 15% sulfuric acid until 1% hydroysis occured. These ATSs had relative molecular weight ranges of 25,00–29,000 daltons. In water, about half the molecules were reconstituted into large aggregates of a few million daltons. This change in molecular size depended on presence of potassium chloride. It was not observed in debranched samples. The aggregates showed a clear endothermic peak on a DSC curve. Thus, the reversibly rearranging starch chain populations were not linear, but were branched and had some type of ordered structure.     

Further Studies on the Roles of the Head and Tall Regions of the Myosin Molecule in Heat-induced Gelation

Heat induced gelation properties of the two proteolytic fragments of myosin, heavy (HMM) and light meromyosin (LMM), were studied by rigidity measurement in a band type viscometer and by a direct examination using a scanning electron microscope. A heat induced network forming ability for both LMM and HMM was found in 0.6M KCl at a pH 6.0. LMM produced gels corresponding to a reversible helix-coil transition at temperatures ranging from 40–70°C, with little evidence of aggregation as assessed from a turbidity change of the system. Contrary, HMM associated irreversibly producing a gel with increased rigidity at pH 5.0 and a salt concentration of 0.1 M. Oxidation of SH-groups appeared to be involved only in HMM and not in LMM gelation process.     

Relative Roles of the Head and Tail Portions of the Molecule in Heat-Induced Gelation of Myosin

Myosin molecules are cleaved by chymotrypsin digestion into two fragments: subfragment 1, which originates from the globular heads of myosin, and the myosin rod, which originates from the helical tail of the myosin molecule. The heat-induced gelation of these subfragments was compared to that of intact myosin by measuring rigidity, turbidity, and other physico-chemical characteristics of each system. Two features of the heat-induced gelation of myosin, aggregation and three-dimensional network formation were found to be imparted by the subfragment 1 and the rod, respectively. The former involves disulfide exchange and the latter relates to conformational changes arising from a partially irreversible helix-coil transition during heating. Possible relationships are suggested between these physicochemical changes of the myosin head and tail regions upon heating and the heat-induced gelation of myosin.     

A HIGHER ORDER EXPANSION METHOD FOR OPTIMUM DESIGN OF STRUCTURES FOR SPECIFIED FUNDAMENTAL EIGENVALUE

A higher order expansion method is presented for optimum design of structures for specified fundamental eigenvalue. The design function, fundamental eigenmode and total volume are expressed in terms of the Taylor series expansion with respect to the specified fundamental eigenvalue. A solution with null design function, where all the eigenvalues degenerate to null, is chosen as a trivial initial solution, and higher order terms are incorporated. By using the proposed method, a set of optimum designs for a wide range of fundamental eigenvalues is easily found. The proposed method is applied to an Euler-Bernoulli beam and expanded forms are presented analytically for a simply supported beam. The method is then extended to a plane truss, and the results are compared with those by an optimality criteria method.     

Anti-E. coli lmmunoglobulin Y Isolated from Egg Yolk of Immunized Chickens as a Potential Food Ingredient

Active immunoglobulin (IgY) was isolated from egg yolk of chickens immunized with formalin-treated E. coli. The antibody activity was measured by enzyme-linked immunosorbent assay using E. coli lipopolysaccharide as an antigen. The anti-E. coli IgY aggregated the bacterial cells and inhibited their growth in vitro. IgY was relatively heat-stable without loss in antibody activity by pasteurization. IgY was stable at pH above 4, but was more susceptible to pepsin than bovine IgG, while appreciable activity was retained by IgY after trypsin- and chymotrypsin-digestion. It appears possible, therefore, to use IgY for the fortification of food products, especially infant formulae.     

Functional Improvement of Alginic Acid by Conjugating with β-Lactoglobulin

Two bovine β-lactoglobulin-alginic acid (β-LG-ALG) conjugates were prepared to improve the function of ALG by using water-soluble carbodiimide and the Maillard reaction. Fluorescence studies suggested that the conformation around Trp had been changed in each conjugate and that the surface of each conjugate was covered with polysaccharide chain. Structural analyses with monoclonal antibodies indicated that the conformation around 15Val-29IIe (β -sheet) in each conjugate had changed, while the native structure was maintained around 125Thr-135Lys (α-helix). After conjugating with β -LG, ALG showed retinol-binding and high emulsifying ability. The aggregating property of ALG in acid and in the presence of Ca²⁺ was improved in each conjugate.