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31.
32.
Different initial cell concentrations of a recombinant flocculent Saccharomyces cerevisiae MA-R4 were evaluated for their effects on xylose fermentation and glucose–xylose cofermentation. A high initial cell concentration greatly increased both the substrate utilization and ethanol production rates. During xylose fermentation, the highest rates of xylose consumption (2.58 g/L h) and ethanol production (0.83 g/L h) were obtained at an initial cell concentration of 13.1 g/L. During cofermentation, the highest rates of glucose consumption (14.4 g/L h), xylose consumption (2.79 g/L h), and ethanol production (6.68 g/L h) were obtained at an initial cell concentration of 12.7 g/L. However, a high initial cell density had no positive effect on the maximum ethanol concentration and ethanol yield mainly due to the increased amount of by-products including xylitol. The ethanol yield remained almost constant (0.34 g/g) throughout xylose fermentation (initial cell concentration range, 1.81–13.1 g/L), while it was slightly lower at high initial cell concentrations (9.87 and 12.7 g/L) during cofermentation. The determination of the appropriate initial cell concentration is necessary for the improvement of substrate utilization and ethanol yield. 相似文献
33.
Yoshinao Kumagai Yuuki Enatsu Masanari Ishizuki Yuki Kubota Jumpei Tajima Toru Nagashima Hisashi Murakami Kazuya Takada Akinori Koukitu 《Journal of Crystal Growth》2010,312(18):2530-2536
Void formation at the interface between thick AlN layers and (0 0 0 1) sapphire substrates was investigated to form a predefined separation point of the thick AlN layers for the preparation of freestanding AlN substrates by hydride vapor phase epitaxy (HVPE). By heating 50–200 nm thick intermediate AlN layers above 1400 °C in a gas flow containing H2 and NH3, voids were formed beneath the AlN layers by the decomposition reaction of sapphire with hydrogen diffusing to the interface. The volume of the sapphire decomposed at the interface increased as the temperature and time of the heat treatment was increased and as the thickness of the AlN layer decreased. Thick AlN layers subsequently grown at 1450 °C after the formation of voids beneath the intermediate AlN layer with a thickness of 100 nm or above self-separated from the sapphire substrates during post-growth cooling with the aid of voids. The 79 μm thick freestanding AlN substrate obtained using a 200 nm thick intermediate AlN layer had a flat surface with no pits, high optical transparency at wavelengths above 208.1 nm, and a dislocation density of 1.5×108 cm−2. 相似文献
34.
Advances in Data Analysis and Classification - 相似文献
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36.
Hitomi Kawakami Takahisa Sakurai Yoshiyasu Ehara Toshiaki Yamamoto Akinori Zukeran 《Journal of Electrostatics》2013,71(6):1117-1123
The novel electrohydrodynamically-assisted electrostatic precipitator (EHD ESP) was developed to suppress particle reentrainment for collection of low resistive diesel particulates. The collection efficiency was compared between vertically and horizontally oriented electrodes of the EHD ESP using 400 cc diesel engine. The particle size dependent collection efficiency was evaluated for the particle size ranging in 20 to 5000 nm using a scanning mobility particle sizer (SMPS) and a particle counter (PC). Both horizontally and vertically oriented EHD ESP showed an excellent suppression of particle reentrainment. However, the horizontally oriented electrode EHD ESP showed significantly improved for the particle size of 300–500 nm in comparison with vertically oriented electrode EHD ESP, resulting in more than 90% collection efficiency for all particle size range. The EHD ESP has high potential especially for highly concentrated marine diesel engine emission control. 相似文献
37.
Hirotaka Ogawa Akinori Kan Norihiro Ikeda Akihiro Fujita 《Physica B: Condensed Matter》2012,407(21):4308-4312
The effect of In doping on the electroluminescence (EL) properties of Zn2SiO4:In thin films was investigated. In-doped Zn2SiO4 thin films were deposited on BaTiO3 substrates and their EL properties were characterized in this study. X-ray powder diffraction patterns of In-doped Zn2SiO4 powders revealed a single phase of Zn2SiO4 for In concentrations up to approximately 1.5 mol%, whereas a secondary phase of In2O3 was observed for In concentrations in the range of 2–10 mol%. The maximum luminance of thin film electroluminescent (TFEL) devices varied significantly with the amount of In doping. The highest luminance with blue emission was obtained when 2 mol% In was doped. The blue emission of In-doped Zn2SiO4 thin film may be related to the In substitution for Zn. The 2 mol% In-doped Zn2SiO4 thin film exhibited blue emission with CIE color coordinates of x=0.208 and y=0.086. 相似文献
38.
Yu Nagao Akinori Takasu 《Journal of polymer science. Part A, Polymer chemistry》2010,48(19):4207-4218
Click Cu(I)‐catalyzed polymerizations of diynes that contained ester linkages and diazides were performed to produce polyesters (click polyesters) of large molecular weights [(~1.0–7.0 ) × 104], that contained main‐chain 1,4‐disubstitued triazoles in excellent yields. Incorporation of triazole improved the thermal properties and magnified the even‐odd effect of the methylene chain length. We also found that, by changing the positions of the triazole rings, the thermal properties of the polyesters could be controlled. The use of in situ azidation was a safe reaction, as explosive diazides are not used. In addition, the microwave heating was found to accelerate the polymerization rates. This is the first study that has applied click chemistry for the synthesis of a series of polyesters. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 4207–4218, 2010 相似文献
39.
Radical additions of S-thiophosphinyl dithiocarbonate to terminal aromatic alkynes afford (E)-1-aryl-1-thio-2-thiophosphinylethene derivatives regio- and stereoselectively in high yields. The transformations of the products are also described. 相似文献
40.