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排序方式: 共有294条查询结果,搜索用时 265 毫秒
241.
To obtain light, strong materials with high thermal conductivity, a new carbon-based material, AlN ceramic bonded carbon (AlN/CBC), was fabricated by combining gelcasting and spark plasma sintering techniques. The results showed that AlN/CBC (20 vol% AlN) has a unique microstructure containing carbon grains of 15 μm in size and an AlN grain-boundary layer of 0.5-3 μm in thickness. Continuous AlN ceramic networks bonded the carbon grains together. Compared with the conventional AlN/carbon (AlN/C) material made by a ball-milling method, AlN/CBC showed a higher strength and a higher thermal conductivity by two and four times, respectively. 相似文献
242.
The influence of oscillation condition on the electrical power generation properties of lead zirconate titanate (PZT) piezoelectric ceramics is investigated. It is found that the power generation increases with an increase of both applied load and load frequency. At lower loading frequencies, e.g., 0.1 and 0.5 Hz, the voltage rises instantly to the maximum level under square-wave mode, although the voltage increases gradually under triangular-wave mode. After this initial increase, there is a rapid fall to zero, followed by generation of increasingly negative voltage as the applied load is removed for both wave modes. Variation of the voltage is reflected by the cyclic loading at higher loading frequencies, 15 and 30 Hz. On the basis of the obtained experimental results for the two wave modes, the electrical power generation characteristics of PZT ceramics are proposed, and the voltages generated during loading and unloading are accurately estimated by numerical analysis. 相似文献
243.
The adsorption of iodine from aqueous solution by coals of different rank was studied. The interaction between coal and iodine was measured by e.s.r. Maximum values for iodine take up were obtained at 87 wt % C (daf) coal by adsorption experiments. The spin concentration ratio between coal and the coal—iodine complex obtained from the e.s.r. experiments also showed a maximum at the same wt % C value. Oxidation of coal decreases its ability to form charge-transfer complexes and this phenomenon may be related to the formation of crosslinks between oxygenated functional groups in coal. 相似文献
244.
Kazuhiro Maeda Ken Yoshida Tetsuro Nishizawa Kazuhiro Otani Yu Yamashita Hinako Okabe Yuka Hadano Tomohiro Kayama Daitaro Kurosaka Mitsuru Saito 《International journal of molecular sciences》2022,23(5)
Rheumatoid arthritis (RA) is an inflammatory disease characterized by a variety of symptoms and pathologies often presenting with polyarthritis. The primary symptom in the initial stage is joint swelling due to synovitis. With disease progression, cartilage and bone are affected to cause joint deformities. Advanced osteoarticular destruction and deformation can cause irreversible physical disabilities. Physical disabilities not only deteriorate patients’ quality of life but also have substantial medical economic effects on society. Therefore, prevention of the progression of osteoarticular destruction and deformation is an important task. Recent studies have progressively improved our understanding of the molecular mechanism by which synovitis caused by immune disorders results in activation of osteoclasts; activated osteoclasts in turn cause bone destruction and para-articular osteoporosis. In this paper, we review the mechanisms of bone metabolism under physiological and RA conditions, and we describe the effects of therapeutic intervention against RA on bone. 相似文献
245.
Kiyo Arai Yoshikazu Fukuyama Tatsuya Iizaka Tetsuro Matsui 《Electrical Engineering in Japan》2019,207(4):25-35
This paper proposes dependable multi‐population improved brain storm optimization with differential evolution for optimal operational planning of energy plants. The problem can be formulated as a mixed‐integer nonlinear programming problem and various evolutionary computation techniques such as particle swarm optimization (PSO), differential evolutionary PSO (DEEPSO), multi‐population DEEPSO (MP‐DEEPSO), and brain storm optimization have been applied so far. When optimal operational planning of numbers of energy plants is calculated simultaneously in a data center, a challenge is to generate optimal operational planning as rapidly as possible considering control intervals and numbers of treated plants. One of the solutions for the challenge is speeding up by parallel and distributed computing. It utilizes numbers of processes and countermeasures for various faults of the distributed processes should be considered. Moreover, successive calculation at every control interval is required for keeping customer services. Therefore, sustainable (dependable) calculation keeping appropriate solution quality is required even if some of the calculation results cannot be returned from distributed processes. It is verified that total energy cost by the proposed dependable multi‐population improved brain storm optimization with differential evolution strategy based method is lower than those by the compared methods, and higher quality of solutions can be kept even with high fault probabilities. 相似文献
246.
Waterborne coatings are composed of resins containing hydrophilic functional groups. These groups usually remain in the coating
film and can adversely affect film properties such as weatherability and resistance to water and alkali. We have developed
a novel ambient temperature curable waterborne two-component system, in which the hydrophilic functional groups are consumed
by the crosslinking reaction. The new coating system consists of a waterborne acrylic resin containing both tert-amino and
carboxylic acid groups and a hardener containing both epoxy and alkoxysilyl groups. The waterborne silicone acrylic coatings
provide superior film properties even if the acrylic resin has relatively low functional group content.
In this paper we describe the crosslinking reaction mechanism and film properties using some acrylic resin types and paint
formulations as examples.
Presented at the 24th Annual Waterborne, High-Solids, and Powder Coatings Symposium, on February 5–7, 1997, in New Orleans,
LA.
1-3 Takasago, Takaishi-shi, Osaka, Japan. 相似文献
247.
Liqiang Cao Congcong Wu Qin Hu Tetsuro Jin Bo Chi Jian Pu Li Jian 《Journal of the American Ceramic Society》2013,96(2):549-554
Here, we report a novel double‐layer structure photoanode with TiO2 nanotube (TNT) layer and TiO2 nanoparticle (TP) layer via a two‐step method of electrochemical anodization and screen printing for dye‐sensitized solar cells (DSSCs). The results indicate that DSSCs with this double‐layer structure have significant advantages of large surface area, long electron lifetime, superior electron recombination restraint characteristics, and high light scattering. The layer thickness of nanotubes and nanoparticles is also investigated and finally an optimized double‐layer structure with excellent performance is prepared. With such a double‐layer structure photoanode, DSSC with a relative high conversion efficiency of 6.43% and a short‐circuit photocurrent density of 16.40 mA·cm?2 is obtained. 相似文献
248.
A new carbon composite called ceramic bonded carbon (CBC) is composed of separated carbon particles bonded with thin ceramic boundaries. To fabricate reliable plasma facing components, AlN ceramic bonded carbon (AlN/CBC, 20 vol.% AlN) was directly cladded with tungsten (W) at 1700 °C by spark plasma sintering. The cladding shows strong bonding, which is attributed to the formation of interface layer containing mixed WC/W2C and AlN ceramic. The interface between W and AlN/CBC was analyzed and the cladding mechanism was discussed. 相似文献
249.
250.
Geographic Information Systems-Based Three-Dimensional Critical Slope Stability Analysis and Landslide Hazard Assessment 总被引:2,自引:0,他引:2
Mowen Xie Tetsuro Esaki Guoyun Zhou Yasuhiro Mitani 《Canadian Metallurgical Quarterly》2003,129(12):1109-1118
In this paper, by combining the geographic information systems (GIS) spatial analysis function and a hydrologic analysis and modeling tool with a column-based three-dimensional (3D) slope stability analysis model, a new GIS grid-based 3D deterministic model has been developed for slope stability analysis. Assuming the initial slip as the lower half of an ellipsoid, the identification of the 3D critical slip surface in the 3D slope stability analysis is performed by means of a minimization of the 3D safety factor using Monte Carlo random simulation. By using this hydrologic analysis and modeling tool, dividing the whole study area into slope units, and taking each slope unit as a study object, the minimum 3D safety factor for each slope unit can be obtained, and the landslide hazard can then be mapped for the whole study area. 相似文献