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11.
Yusuke Tsuda Yonghao Yue Yoshinori Dobashi Tomoyuki Nishita 《The Visual computer》2010,26(6-8):883-891
In the field of computer graphics, simulation of fluids, including avalanches, is an important research topic. In this paper, we propose a method to simulate a kind of avalanche, mixed-motion avalanche, which is usually large and travels down the slope fast, often resulting in impressive visual effects. The mixed-motion avalanche consists of snow smokes and liquefied snow which form an upper suspension layer and a lower dense-flow layer, respectively. The mixed-motion avalanche travels down the surface of the snow-covered mountain, which is called accumulated snow layer. We simulate a mixed-motion avalanche taking into account these three snow layers. We simulate the suspension layer using a grid-based approach, the dense-flow and accumulated snow layer using a particle-based approach. An important contribution of our method is an interaction model between these snow layers that enables us to obtain the characteristic motions of avalanches, such as the generation of the snow smoke from the head of the avalanche. 相似文献
12.
Akira Akahira K. C. A. Alam Yoshinori Hamamoto Atsushi Akisawa Takao Kashiwagi 《International Journal of Refrigeration》2004,27(3):530
The study investigates the performance of two-bed, silica gel-water adsorption refrigeration cycle with mass recovery process. The cycle with mass recovery can be driven by the relatively low temperature heat source. In an adsorption refrigeration cycle, the pressures in adsorber and desorber are different. The chiller with mass recovery process utilizes the pressure difference to enhance the refrigerant mass circulation. Cooling capacity and coefficient of performance (COP) were calculated by cycle simulation computer program to analyze the influences of operating conditions. The mass recovery cycle was compared with conventional cycle such as the single stage adsorption cycle in terms of cooling capacity and COP. The results show that the cooling capacity of mass recovery cycle is superior to that of conventional cycle and the mass recovery process is more effective for low regenerating temperature. 相似文献
13.
Asahiko Matsuda Yoshinori Nakakubo Yoshinori Takao Koji Eriguchi Kouichi Ono 《Thin solid films》2010,518(13):3481-3486
Structures and mechanism of ion-bombardment damage on silicon wafers exposed to plasma were investigated comprehensively. By using molecular dynamics simulations high-resolution transmission electron microscopy, and composition analysis by high-resolution Rutherford backscattering spectroscopy, features such as gradual transition from the SiO2 surface to the Si substrate and interface roughness were addressed. On the basis of these findings, the optical model that addresses the characteristics of plasma-damaged Si surfaces is given for ellipsometric analysis. The proposed model includes an interface layer modeled as a mixture of SiO2 and Si phases. A part of the interface layer could not be removed by wet-etching, signifying the distinct features of the interface layer that are difficult to remove. The proposed model is anticipated to be practical for in-line monitoring of plasma-induced damage. 相似文献
14.
毛细管电泳仪具有灵敏度高、分析速度快等优势,为降低其生产成本,基于电泳原理,以荧光显微镜为基础,设计了一套毛细管电泳系统。以20 bp(base pairs,碱基对)DNA ladder和100 bp DNA ladder为样本,全面分析了系统的稳定性、灵敏度和分离效果。结果表明:该系统在9 min内可以实现1500 bp以内DNA片段的高效分离,系统检测极限为0.1 ng/μL;在优化的电泳条件下,对限制性内切酶φX174-HincⅡ作用过的λ-DNA片段5 min内实现了291 bp与297 bp DNA片段的区分。 相似文献
15.
Shin Takasawa Ryogo Shobatake Yoshinori Takeda Tomoko Uchiyama Akiyo Yamauchi Mai Makino Sumiyo Sakuramoto-Tsuchida Keito Asai Hiroyo Ota Asako Itaya-Hironaka 《International journal of molecular sciences》2022,23(11)
Sleep apnea syndrome (SAS), characterized by recurrent episodes of oxygen desaturation and reoxygenation (intermittent hypoxia (IH)), is a risk factor for hypertension and insulin resistance. We report a correlation between IH and insulin resistance/diabetes. However, the reason why hypertension is induced by IH is elusive. Here, we investigated the effect of IH on the expression of catecholamine-metabolizing enzymes using an in vitro IH system. Human and mouse neuroblastoma cells (NB-1 and Neuro-2a) were exposed to IH or normoxia for 24 h. Real-time RT-PCR revealed that IH significantly increased the mRNA levels of dopamine β-hydroxylase (DBH) and phenylethanolamine N-methyltransferase (PNMT) in both NB-1 and Neuro-2a. Western blot showed that the expression of DBH and PNMT in the NB-1 cells was significantly increased by IH. Reporter assays revealed that promoter activities of DBH and PNMT were not increased by IH. The miR-375 level of IH-treated cells was significantly decreased relative to that of normoxia-treated cells. The IH-induced up-regulation of DBH and PNMT was abolished by the introduction of the miR-375 mimic, but not by the control RNA. These results indicate that IH stress increases levels of DBH and PNMT via the inhibition of miR-375-mediated mRNA degradation, potentially playing a role in the emergence of hypertension in SAS patients. 相似文献
16.
17.
Single‐Crystal‐Like Organic Thin‐Film Transistors Fabricated from Dinaphtho[2,3‐b:2′,3′‐f]thieno[3,2‐b]thiophene (DNTT) Precursor–Polystyrene Blends 下载免费PDF全文
18.
Tatsumi Ishihara Kuninobu Shimose Takanari Kudo Hiroyasu Nishiguchi Taner Akbay Yusaku Takita 《Journal of the American Ceramic Society》2000,83(8):1921-1927
A yttria-stabilized zirconia (YSZ) thin film on an La0.8 Sr0.2 MnO3 porous cathode substrate was prepared, using electrophoretic deposition (EPD) to fabricate a solid oxide fuel cell (SOFC). The electrical conductivity of an La0.8 Sr0.2 MnO3 substrate is satisfactorily high at room temperature; therefore, YSZ powder could be deposited electrophoretically onto an La0.8 Sr0.2 MnO3 substrate without any extra surface treatment, such as a metal coating. Successive repetition of EPD and sintering was required to obtain a film without gas leakage, because of the thermal expansion coefficient mismatch between the YSZ and the La0.8 Sr0.2 MnO3 substrate. On the other hand, the electromotive force of the oxygen concentration in the cell that used YSZ film prepared via EPD increased and attained the theoretical value when the number of deposition and calcination cycles was increased. Six or more successive repetitions were required to obtain a YSZ film without gas leakage. A planar-type SOFC was fabricated, using nickel as the anode and YSZ film (∼10 μm thick) that had been deposited onto the La0.8 Sr0.2 MnO3 substrate as the electrolyte and cathode. The cell exhibited an open circuit voltage of 1.0 V and a maximum power density of 1.5 W/cm2 . Thus, the EPD method could be used as a colloidal process to prepare YSZ thin-film electrolytes for SOFCs. 相似文献
19.
Metabolic Activation of Heterocyclic Amines and Expression of Xenobiotic‐Metabolizing Enzymes in the Gastrointestinal Tract of Rats 下载免费PDF全文
Wageh S. Darwish Shouta M. M. Nakayama Yuumi Itotani Marumi Ohno Yoshinori Ikenaka Mayumi Ishizuka 《Journal of food science》2015,80(7):T1627-T1632
Heterocyclic amines get entry into human body mainly through ingestion of pan‐fried meats cooked at high temperatures. Exposure of the gastrointestinal tract (GIT) to ingested xenobiotics prior to delivery to the liver may lead to metabolic activation, which may explain the high incidence of GIT carcinogenesis. Therefore, this study investigated the mutagenic activation of 2 heterocyclic amines, 2‐aminoanthracene (2‐AA) and 3‐amino‐1‐methyl‐5H‐prydo[4,3‐b]indole (Trp‐P‐2), in the GIT of rats. In addition, the constitutive mRNA expression profiles of xenobiotic‐metabolizing enzymes (XMEs) in the GIT of rats were examined. Metabolic activation of 2‐AA was detected in all GIT tissues except the duodenum and rectum, and it was detected at high levels in the ileum and cecum. Furthermore, we revealed high metabolic activation of 2‐AA and Trp‐P‐2 in the jejunum. The mRNA expression of phase I and II enzymes in rat GIT corresponded with their mutagenic activation ability. In conclusion, our results suggest that different expression levels of XME among GIT tissues may contribute to the tissue‐specific differences in metabolic activation of xenobiotics such as heterocyclic amines in rats. 相似文献
20.
Ko Ikeda Yoshinori Nakamura Kiyoshi Masumoto Hiromi Shima 《Journal of the American Ceramic Society》1997,80(10):2672-2676
Unpolarized optical spectra were measured in the wavelength range 322–1666 nm by the diffuse reflection technique from spinel powders synthesized in the system MgAl2 O4 –MgCr2 O4 . The spectra were interpreted by the crystal-field theory on the basis of trigonally distorted spinel octahedra with D3d symmetry. For chromium-rich solid solutions, including the MgCr2 O4 end-member, results after peak fittings showed octahedral D3d local symmetry around Cr3+ ions, identical to the crystallographic site symmetry. For chromium-poor solid solutions, however, octahedral C3v local symmetry was suggested around Cr3+ ions, different from the D3d crystallographically expected. 相似文献