Identification of global modeshape from a few nodal eigenvectors using simple free-form deformation

A new method, different from common eigenvalue extraction methods, was proposed by Li and Kikuchi (in 8th ARC conference, 2002). It consists of explicit finite-element method and eigenvalue-extraction method in time domain. Even though the new method performs well in extracting eigenvalues, it is difficult to identify global modeshape of the given structure due to large size of time history data. Only some eigenvectors of a few nodal points can be extracted. In this paper, we apply computer animation technique to identify the global modeshape from a few nodal eigenvectors. Free-form deformation (FFD) technique is simply modified—simple FFD—and applied to the identification of global modeshapes. The basic concepts that consist of simple FFD algorithm are Delaunay triangulation and barycentric coordinate. Some numerical examples show good performance for the identification of global modeshape of a given structure.     

燃料挥发性对柴油机性能及排放的影响

针对不同的发动机热状态及压缩比，试验研究了燃料物化特性对柴油机稳态及过渡工况下性能、排放的影响规律。应用自行开发的柴油机过渡工况控制系统及排气采集装置，模拟车用柴油机实际工作时的加速状态，对具有相同十六烷值但有不同挥发性能燃料的HC排放特性进行了研究，利用气相色谱仪对HC排放成分进行了分析。研究结果表明，采用挥发性好的燃料，可有效降低排气烟度，提高有效热效率，在发动机热状态不好及压缩比较低等燃烧条件恶劣、HC排放高的情况下，可有效地降低HC排放。     

Manufacture of three-layer wood–porcelain stone composite board reinforced with bamboo fiber

The objective of this study was to improve bending strength properties of three-layer wood–porcelain stone composite board. The focus of this study was on the effects of orientations and weight ratios of bamboo fiber in face layer on physical and mechanical properties of the board. Three types of board with different orientation of bamboo fibers in the face layer were manufactured: one in which the fibers were oriented at random orientation (R board), another in which the fibers were oriented at unidirectional orientation (U board), and a third in which the fibers were oriented at cross orientation (C board). The physical and mechanical properties of the boards were evaluated based on the Japanese Industrial Standard for Particleboards. The main results obtained were as follows: Bending strength properties of the board were strongly affected by both orientation and weight ratio of bamboo fibers. Perpendicular specimen of C board has larger bending strength properties than U board and the value become larger with increased weight ratio of bamboo fibers. Internal bond strength value decreased with increasing weight ratio of bamboo fibers. The effect of orientation and weight ratios of bamboo fiber on thickness swelling of the board was not significant.     

Power and temperature distribution during microwave thawing, simulated by using Maxwell's equations and Lambert's law

The microwave thawing of frozen food was simulated by using an equation to describe heat conduction. This was based on the fact that the thermal and dielectric properties of food vary with temperature. The microwave power absorbed was modelled by using Maxwell's equations and Lambert's law. The power and temperature distributions calculated using both models were compared. Although Lambert's law is theoretically less applicable for simulating the transmitted microwave power, it provided an effective numerical approach for calculating temperature distribution during microwave thawing, which proved compatible with experimental results.     

Preparation of CdS-doped Glasses from Gels Containing Diethyldithiocarbamatocadmium

CdS-doped SiO₂ glasses were prepared via silica gels containing diethyldithiocarbamatocadmium Cd(S₂CN(C₂H₅)₂)₂. Heat treatment of the gels gave transparent yellow SiO₂glasses doped with hexagonal CdS crystals. In optical absorption and fluorescence spectra, the optical absorption edge and the emission peak clearly exhibited a blue shift, which was attributed to the quantum size effect of the carrier confinement, as the CdS content was decreased. In the fluorescence spectra of the CdS-doped silica glasses, the emission peak was observed only near 500 nm and not observed at longer wavelengths which were known to be present if there were sulfur vacancies.     

Preparation of ultrafine zirconium dioxide particles by thermal decomposition of zirconium alkoxide vapour

Ultrafine zirconia particles are produced by thermal decomposition of zirconium tetratertiary butoxide (ZrTB) vapour. The introduction of ZrTB vapour into the cylindrical electric furnace, is achieved by three different methods: (evaporator, pressurized nebulizer and ultrasonic nebulizer). The properties of the fine particles obtained by these methods are mainly analysed by X-ray diffraction and transmission electron microscopy. It is found that ultrafine zirconia particles produced at relatively low temperatures from 600 to 700° C are spherical in the diameter range 0.035 to 0.15 μm and of tetragonal phase. Furthermore, two-component fine particles of zirconia-ilver are generated by putting the silver solid inside the furnace containing alkoxide vapour, and are deposited by inertia on to a glass substrate under low pressure to form films having a thickness of 17 to 33 μm. The electrical characteristics of the films are evaluated, and the conductance of the film is found to increase with the content of the silver component.     

Gene therapy for malignant gliomas using replication incompetent retroviral and adenoviral vectors encoding the cytochrome P450 2B1 gene together with cyclophosphamide

Cyclophosphamide is an inactive prodrug which is converted by hepatic cytochrome P450 2B1 to cytotoxic metabolites which produce interstrand DNA cross-linking in a cell cycle-independent fashion. The limited ability of these metabolites to cross the blood-brain barrier contributes to the poor activity of cyclophosphamide against brain tumors. In this study we demonstrate that replication deficient retroviral and adenoviral vector-mediated gene transfer of cytochrome P450 2B1 into 9L glioma cells significantly increases the sensitivity of these tumor cells to cyclophosphamide in vitro, and prolongs the survival of animals bearing intracerebral 9L tumors treated with cyclophosphamide in vivo. Attempts to improve the effectiveness of retrovirally mediated transduction of the P450 2B1 gene by increasing the concentration of cyclophosphamide delivered to the tumors using intracarotid and intratumoral injections did not prolong animal survival, although survival was increased when a second treatment with P450-expressing retroviral vectors and cyclophosphamide was administered. These results suggest that in situ transduction of tumor cells with the P450 2B1 gene using retroviral and adenoviral vectors increases their sensitivity to cyclophosphamide and may have a potential role in the therapy of malignant gliomas.     

Reactions between zirconium/permalloy bilayer thin films

The interdiffusion and reactions of zirconium/permalloy bilayer thin films annealed at 150 to 350 °C were investigated. Nickel atoms preferentially diffuse from the permalloy layer into the zirconium layer. This preferential diffusion results in the growth of an amorphous phase between the zirconium and permalloy thin films. Consequently, the magnetic properties of the permalloy thin layer in the bilayer thin films change. The starting temperature of interdiffusion between zirconium and permalloy films is higher than that of a titanium/permalloy system reported previously.