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101.
试验了彩色聚乙烯涂覆钢管的耐腐蚀性和耐气候性,由于聚乙烯涂层隔绝水的作用,聚乙烯涂覆钢管具有优良的耐腐蚀性能,电阻绝缘值和优良的机械性能。建立了一个新的方式去研究分析聚乙烯抗老化剂消耗和在聚乙烯中的扩散。用有效测定的方法定量地预测彩色聚乙烯涂覆层的寿命,应用这些分析结果,不仅可使新的有色聚乙烯涂覆钢管在恶劣腐蚀环境介质情况下具有高的耐腐蚀性,而且有长的耐气候性。 相似文献
102.
Akihiko Nakajima Takayuki Suzuki Masashi Yoshimi Kenji Yamamoto 《Solar Energy Materials & Solar Cells》1997,48(1-4)
Optical confinement effect of thin-film polycrystalline-Si (poly-Si) solar cell on glass substrate fabricated at low-temperature has been investigated as a function of cell thickness of less than 5 μm. We found that it is possible to fabricate the textured Si thin film in situ on a glass substrate and that the reflectance at long-wavelength light is reduced by surface texturing. Thin-film poly-Si solar cell and a-Si:H/(0.45 μm)/poly-Si (5 μm) tandem solar cell exhibit the efficiency of 8.6% and 12.8%, respectively. The numerical study in terms of the light trapping explains the excellent high short-circuit current density (sc above 27 mA/cm2 at the 4.7 μm thin-film poly-Si solar cell. 相似文献
103.
Seigo Ito Takayuki Kitamura Yuji Wada Shozo Yanagida 《Solar Energy Materials & Solar Cells》2003,76(1):3-13
A chemical dispersing technique for preparing a coating paste of TiO2 nanoparticles is disclosed to fabricate mesoporous electrodes for dye-sensitized TiO2 solar cells. The suspension of TiO2 (P-25) powder was stirred in aqueous nitric acid at 80°C, and then evaporated to dryness, giving the nitric acid-adsorbed P-25 powder. The coating paste was obtained by mixing the nitric acid-adsorbed P-25 with PEG (Mw 20,000) as a porosity-controlling agent and cellulosic polymer as a thickener. The mesoporous TiO2 films were fabricated on conducting glasses by repetitive coating and calcined at 500°C (30 min). The TiO2 film obtained by the five times repetitive coating (20 μm thickness) resulted in the 1.4 times higher energy conversion efficiency of the dye-sensitized solar cells than that of the one time coating TiO2 film (Voc=690 mV, Jsc=12.2 mA/cm2, the fill FACTOR=0.71 and η=6.0%). 相似文献
104.
Shirasuna K Watanabe S Asahi T Wijayagunawardane MP Sasahara K Jiang C Matsui M Sasaki M Shimizu T Davis JS Miyamoto A 《Reproduction (Cambridge, England)》2008,135(4):527-539
Prostaglandin F(2)(alpha) (PGF(2)(alpha)) released from the uterus causes alterations in luteal blood flow, reduces progesterone secretion, and induces luteolysis in the bovine corpus luteum (CL). We have recently discovered that luteal blood flow in the periphery of the mature CL acutely increases coincidently with pulsatile increases in a metabolite of PGF(2)(alpha) (PGFM). In this study, we characterized changes in regional luteal blood flow together with regional alterations in endothelial nitric oxide synthase (eNOS) expression during spontaneous luteolysis and in response to PGF(2)(alpha). Smooth muscle actin-positive blood vessels larger than 20 microm were observed mainly in the periphery of mature CL. PGF(2)(alpha) receptor was localized to luteal cells and large blood vessels in the periphery of mid-CL. PGF(2)(alpha) acutely stimulated eNOS expression in the periphery but not in the center of mature CL. Injection of the NO donor S-nitroso-N-acetylpenicillamine into CL induced an acute increase in luteal blood flow and shortened the estrous cycle. In contrast, injection of the NOS inhibitor l-NAME into CL completely suppressed the acute increase in luteal blood flow induced by PGF(2)(alpha) and delayed the onset of luteolysis. In conclusion, PGF(2)(alpha) has a site-restricted action depending on not only luteal phase but also the region in the CL. PGF(2)(alpha) stimulates eNOS expression, vasodilation of blood vessels, and increased luteal blood flow in periphery of mature CL. Furthermore, the increased blood flow is mediated by NO, suggesting that the acute increase in peripheral blood flow to CL is one of the first physiological indicators of NO action in response to PGF(2)(alpha). 相似文献
105.
Takayuki Ohba 《Journal of Electronic Materials》2001,30(4):314-319
In order for ultra-large-integrated (ULSI) circuits manufacturing to minimize the Cost of Ownership (CoO) aspect in the wiring
process and realize fabricating semiconductor devices over 100 nm node, several Cu/low-k wiring technologies have been proposed.
The evidential criteria in choosing the most probable one are physical or material limitation and requirements from manufacturing.
A development of module processes (e.g., processing from low-k dielectrics to metal CMP) with proven equipment and material
is an appropriate approach and has a high potential in overcoming those difficulties. In this paper, an advantage of dual
Damascene Cu wiring accompanied with low-k (dielectric constant ∼2.7) and prediction of 100 nm Cu wiring module will be discussed. 相似文献
106.
Takayuki Watanabe Masaya Shigeta Nobuhiko Atsuchi 《International Journal of Heat and Mass Transfer》2006,49(25-26):4867-4876
A non-equilibrium modeling of argon–oxygen and argon–hydrogen induction thermal plasmas was performed without thermal and chemical equilibrium assumptions. Reaction rates of dissociation and recombination of diatomic gas and ionization were taken into account with two-temperature modeling. A substantial deviation from LTE exists near the torch wall in argon–oxygen induction plasmas under atmospheric pressure, while small deviation in argon–hydrogen plasmas results from the large collision frequency between electrons and hydrogen atoms. 相似文献
107.
Tomokazu Fukutsuka Takayuki Yamaguchi Shin-Ichi Miyano Yoshiaki Matsuo Yosohiro Sugie Zempachi Ogumi 《Journal of power sources》2007
Stainless steel is quite attractive as bipolar plate material for polymer electrolyte fuel cells (PEFCs). Passive film on stainless steel protects the bulk of it from corrosion. However, passive film is composed of mixed metal oxides and causes a decrease in the interfacial contact resistance (ICR) between the bipolar plate and gas diffusion layer. Low ICR and high corrosion resistance are both required. In order to impart low ICR to stainless steel (SUS304), carbon-coating was prepared by using plasma-assisted chemical vapor deposition. Carbon-coated SUS304 was characterized by Raman spectroscopy and atomic force microscopy. Anodic polarization behavior under PEFC operating conditions (H2SO4 solution bubbled with H2 (anode)/O2 (cathode) containing 2 ppm HF at 80 °C) was examined. Based on the results of the ICR evaluated before and after anodic polarization, the potential for using carbon-coated SUS304 as bipolar plate material for PEFC was discussed. 相似文献
108.
Jyomoto T Azuma M Islam NN Fujinami R Takao T Ogawa T Tabuchi M Igarashi K Kato J Ooshima H 《Journal of Bioscience and Bioengineering》2006,102(3):193-197
The enzyme that catalyzes N-acyl linkage between myristic acid and the NH(2)-terminal glycine residue of the octapeptide Gly-Asn-Ala-Ala-Ala-Ala-Arg-Arg-NH(2) in aqueous solution without ATP and coenzyme A was found in Pseudomonas aeruginosa. The enzyme was purified from cell-free crude extract using DEAE-Cellulose, Sephadex G-200, CM-Sephadex C-50, and hydroxyapatite column chromatographies, and then purified approximately 1900-fold with about 1.5% recovery of enzyme activity from the crude extract. Finally, the purified enzyme showed a main band on SDS polyacrylamide gel electrophoresis after staining with Coomassie Brilliant Blue. The band corresponded to a molecular mass of approximately 60 kDa. The K(m)s of the purified enzyme for the substrate myristic acid and the octapeptide were 0.36 and 2.6 mM, respectively. When myristoyl-CoA instead of myristic acid was used as the substrate for the enzyme reaction, myristoyl octapeptide could be synthesized as observed in the case of myristic acid. The K(m) of myristoyl-CoA was 0.17 mM. 相似文献
109.
Ano A Takayanagi T Uchibori T Okuda T Yokotsuka K 《Journal of Bioscience and Bioengineering》2003,95(6):645-647
A chitinase gene (Chi3K) was cloned from the genomic DNA of Vitis vinifera cv. Koshu. The structural gene comprised 891 by without introns and encoded 297 amino acids. The Chi3K product showed high similarity to the class III chitinase of V. vinifera cv. Pinot noir. Chi3K was expressed using a bacterial expression vector for purification and enzymatic characterization of its gene product. The recombinant chitinase exhibited hydrolytic activity toward glycol chitin and its optimum pH was 4.0. It also inhibited the growth of Botrytis cinerea, which causes grey mold disease in grapes. 相似文献
110.
Yamakawa S Ando K Chisaka A Yoshida K Shinmyo A Kohchi T 《Journal of Bioscience and Bioengineering》2004,98(2):140-143
We identified 85 genes highly expressed in leaves using an Arabidopsis cDNA microarray. A vector, pRAB5, was designed to allow cloning and assaying of the promoters. Fifty-one promoters from the selected genes were cloned and then assayed using a microprojectile bombardment and dual luciferase reporter assay system. This system allowed efficient systematic assays of promoter activity. 相似文献