Hydrodynamics of Superfluid Bose Gases in an Optical Lattice at Finite Temperatures

Starting from an effective action for the order parameter field, we derive a coupled set of generalized hydrodynamic equations for a Bose condensate in an optical lattice at finite temperatures. Using the linearized hydrodynamic equations, we study the microscopic mechanism of the Landau instability due to the collisional damping process between the condensate and noncondensate atoms. It is shown that the Landau criterion for the stability of a superfluid in a uniform system is modified due to the presence of the periodic optical lattice potential.     

Flexural properties of moldings of rigid polyurethane made by reaction injection molding

Flexural properties of moldings made by Reaction Injection Molding (RIM), which are structural foams consisting of high density skin and low density core, were investigated by three-point bending tests. Two failure modes were observed in bending tests of the moldings made by RIM, and they are classified as follows according to the density ratio of skin layer to core layer: the opposite side of the skin layer to which load was subjected failed by tensile stress: and the same side of the skin layer to which load was subjected failed by compressive stress, causing wrinkling or buckling. Then the conventional composite beam theory was applied to the former failure mode and Hoff s buckling theory to the latter, and equations were derived to predict the flexural properties of the structural foams, which involved buckling from the flexural properties of solid construction. In addition, it has been shown that there exists a density distribution that maximizes the flexural strength of the moldings made by RIM with a given overall density. The results obtained here should be useful to the optimum structural design of moldings made by RIM.     

Copolymerization of methylmethacrylate on a ball-milled surface of coal at 77 K

The ball-milling of coal with methylmethacrylate monomer was carried out under vacuum at 77 K and at room temperature and in air. The e.s.r. and i.r. spectra of ball-milled material showed that a copolymer of coal and methylmethacrylate was formed on the surfaces of coal created by ball-mining. Oxygen is an inhibitor to this process.     

Carbonization and liquid—crystal (mesophase) development. 19. Co-carbonization of oxidized coals with model organic compounds

This study examines further the phenomena of the modification of coal carbonizations by organic additives. Anthracene, pyrene and chrysene modify the carbonization in a closed system of coking coals as observed from increases in the size of optical textures of resultant cokes. Weakly caking coals are unaffected. Chrysene is the most efficient modifier probably because of its lowest calculated free valence. The co-additives tetralin and hydrogenated anthracene oil further enhance the modification processes so obviating the necessity to use hydrogenated additives. Co-carbonizations of oxidized coking and caking coals with decacyclene are effective in removing the effects of mild oxidation. Increased rates of carbonization enhance the sizes of optical textures of resultant cokes.     

Fibrous support for immobilization of enzymes

A poly(vinyl alcohol) (PVA) fiber support incorporating various aminoacetal functional groups has been developed for immobilizing enzymes. The aminated PVA fiber seems to adsorb enzymes with electrostatic force of attraction; thus the immobilization procedure is simple. By the use of this fiber having immobilized enzymes, the reaction between enzymes and substrates is nearly independent of the size of subtstrates. This newly developed type of fiber, which is formed by a mass superfine fibers (SFF), each measuring 1 μm or less in diameter, permits much more increased surface area than the conventional enzyme immobilization supports. Our studies of the properties of the fiber for immobilization of enzymes show the following results: (1) SFF has a greater ability for the immobilization of invertase than ordinary fibers; (2) dimethyl-aminated SFF has the best performance for the immobilization of invertase. From these results, it is concluded that the dimethyl-aminated SFF is an excellent support for the immobilization of invertase.     

In-situ monitoring of the stabilization with hydrogen of free radicals thermally induced from coal using high pressure e.s.r., d.t.a. and p.d.a. equipment

High temperature, high pressure e.s.r. measurements of the hydrogenation reaction of Taiheiyo coal in the presence of catalysts were carried out to understand the stabilization of thermally and/or catalytically induced free radicals. A decrease in free radical concentration with increasing temperature was observed for ZnCl₂ and SnCl₂ · 2H₂O catalysts at 10MPa under hydrogen gas. High pressure modified single-cell d.t.a. and p.d.a. equipment augmented the uniquely designed high temperature, high pressure e.s.r. cell. The hydrogenation reaction was monitored under the same experimental conditions as for e.s.r. From the results of the combination of high temperature, high pressure e.s.r. with high pressure d.t.a. and p.d.a., it was established that H₂ molecules can react efficiently with free radicals from coal molecules created by the presence of ZnCl₂ and SnCl₂ · 2H₂O catalysts.     

Tele‐Cocooning: Mobile Texting and Social Scope

The present study examines the tele‐cocooning hypothesis in the context of general trust using a nationally representative survey of Japanese youth. We find that although frequency of texting is positively correlated with general trust, this correlation is spuriously caused by how heavy mobile texters interpret the words “most people” in the general trust measurement. Heavy users assume that “most people” only refers to friends, family, and others going to the same school. When the effect of the “most people” assumption is controlled, the positive association between texting and general trust disappears. Further exploration of the data shows that heavy texting nevertheless has negative implications for social tolerance and social caution, both of which are theoretically proximate to general trust.     

Relationships between hydrogen donor abilities and chemical structure of aromatic compounds in terms of coal liquefaction

To obtain fundamental information about hydrogen transfer, the relationships between hydrogen donor ability and chemical structure of model compounds representing donor solvents is studied using gas chromatography,¹H n.m.r. and computing calculation methods. The order of the model compounds in terms of the ability as donor solvent to release hydrogen is: decalin < tetralin < 1,2-dihydronaphthalene < < 1,4-dihydronaphthalene. This trend closely correlates with the difference in binding energies of the hydroaromatic compounds and their radicals, determined by intermediate neglect of differential overlap (INDO) calculation. Electron spin resonance spectroscopy (e.s.r.) confirms that radical species are created after heat-treatment of the donor compounds. The ability of model compounds representing coal to accept hydrogen is assessed from a comparison of the¹H n.m.r. spectra. It is established that donor and acceptor efficacies are dependent upon chemical structure.     

Emerging From the Cocoon? Revisiting the Tele‐Cocooning Hypothesis in the Smartphone Era

The tele‐cocooning hypothesis posits that mobile communication increases interaction with communication rich ties, while simultaneously weakening interaction with communication weak ties. In this study, we demonstrate how smartphones can be used to mitigate tele‐cocooning behavior by stimulating interaction with communication weak ties. Using a smartphone application to collect non‐identifying mobile communication log data, we conducted a field experiment with 193 Japanese participants. The treatment consisted of onscreen reminders designed to stimulate interaction with communication weak ties. The results indicate that the treatment promoted the activation of communication weak ties and the acquisition of information through those ties, suggesting that smartphones can be utilized to promote access to social capital.     

基于网络磁盘结构的Local Migration Manager设计

为构成高性能的数据库,磁盘阵列的活用是很有必要的.其中尤为重要的是实现磁盘阵列之间负载的均衡.为此,设计了网络磁盘结构系统,该系统在磁盘阵列高负载的情况下也能够进行动态的负载均衡,并且具有优良的耐故障性.对于网络磁盘结构构成要素中的Local Migration Manager(LMM)进行了设计.列举出了LMM连接的Main Bus上传送的信息,定义了信息形式,信息的传送与Bus的宽度相符呈分割进行;在LMM的设计方法中定义了LMM的内部数据结构;在此基础上,制作了LMM的算法.