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131.
132.
Photocatalytic activities of CdS crystallites embedded in TiO2 gel as a stable semiconducting matrix 总被引:2,自引:0,他引:2
Abstracts are not published in this journal
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
133.
134.
Optimizing the design of large-scale ground-coupled heat pump systems using groundwater and heat transport modeling 总被引:2,自引:0,他引:2
In order to predict the long-term performance of large-scale ground-coupled heat pump (GCHP) systems, it is necessary to take into consideration well-to-well interference, especially in the presence of groundwater flow. A mass and heat transport model was developed to simulate the behavior of this type of system in the Akita Plain, northern Japan. The model was used to investigate different operational schemes and to maximize the heat extraction rate from the GCHP system. 相似文献
135.
H Miyamoto H Yamamoto K Arima J Fujii K Maruta K Izu T Shiomori S Yoshida 《Canadian Metallurgical Quarterly》1997,63(7):2489-2494
The presence of PCR inhibitors in water samples is well known and contributes to the fact that a practical PCR assay has not been developed for legionella surveillance. In this study, we devised a new seminested PCR assay for detection of Legionella spp. in water samples as a means of overriding the PCR inhibitors without loss of sensitivity. The seminested PCR assay utilized primers to amplify the 16S rRNA gene (LEG primers) of 39 Legionella spp. The assay was specific to legionellae, and the sensitivity was 1 fg of extracted Legionella DNA in laboratory examination. To evaluate the feasibility and sensitivity of the PCR assay in identifying the presence of legionellae, it was used to survey Legionella contamination in the water of 49 cooling towers of 32 hospitals. A commercially available EnviroAmp Legionella kit and a culture method were also used in the survey for comparison with the seminested PCR assay. The detection rates of legionellae in the samples were 91.8% (45 of 49) by the PCR assay and 79.5% (39 of 49) by the culture method. The EnviroAmp kit revealed that 30.6% of the water samples (15 of 49) contained inhibitors of the PCR amplification. However, the seminested PCR assay could produce the Legionella-specific DNA bands in 14 of the 15 samples. Although 8 of the 14 samples were positive in the first-step PCR, 6 of the 14 samples became positive in the second-step PCR. These results suggest that the effect of PCR inhibitors in samples, if any, can be reduced because of the dilution of the sample in the second-step PCR and that sensitivity of detection can be increased by the second-step PCR. Thus, the seminested PCR assay with LEG primers to amplify the 16S rRNA gene of 39 Legionella spp. was a practical and sensitive method to detect Legionella spp. in water samples. 相似文献
136.
Hiromichi Fujii Victoria A. Yardley Takashi Matsuzaki Sadahiro Tsurekawa 《Journal of Materials Science》2008,43(11):3837-3847
The effect of a magnetic field on the nature of nanocrystallization from a melt-spun Fe73.5Si13.5B9Nb3Cu1 amorphous precursor has been studied with the aim of controlling microstructures and magnetic properties. Annealing for magnetic
crystallization was carried out at temperatures between the Curie temperature of the amorphous phase (586 K) and that of the
crystalline phase (920 K). It was found that the {110} texture component in crystallized α-Fe(Si) phase increased in importance
with increasing magnetic-field strength. An X-ray diffraction analysis based on the Shultz method revealed that the magnetic
field caused preferential formation of {110}-oriented nuclei. In addition, the applied field enhanced crystallization kinetics,
particularly the nucleation rate. No significant difference in grain growth behavior was observed as a result of applying
a magnetic field. We therefore conclude that the development of the {110} texture by magnetic crystallization is predominantly
attributable to preferential nucleation, rather than preferential growth, of {110}-oriented nuclei. The saturation magnetization
of nanocrystallized specimens, evaluated using a vibrating sample magnetometer (VSM), was increased by the application of
a magnetic field up to 4T during nanocrystallization. 相似文献
137.
138.
Hiromi Yamashita Yo Fujii Yuichi Ichihashi Shu Gou Zhang Keita Ikeue Dal Ryung Park Keiko Koyano Takashi Tatsumi Masakazu Anpo 《Catalysis Today》1998,45(1-4):221-227
Highly dispersed titanium oxide catalysts have been prepared within zeolite cavities as well as in the zeolite framework and utilized as photocatalysts for the reduction of CO2 with H2O to produce CH4 and CH3OH at 328 K. In situ photoluminescence, ESR, diffuse reflectance absorption and XAFS investigations indicate that the titanium oxide species are highly dispersed within the zeolite cavities and framework and exist in tetrahedral coordination. The charge transfer excited state of the highly dispersed titanium oxide species play a significant role in the reduction of CO2 with H2O with a high selectivity for the formation of CH3OH, while the catalysts involving the aggregated octahedrally coordinated titanium oxide species show a high selectivity to produce CH4, being similar to reactions on the powdered TiO2 catalysts. Ti-mesoporous molecular sieves exhibit high photocatalytic reactivity for the formation of CH3OH, its reactivity being much higher than the powdered TiO2 catalysts. The addition of Pt onto the highly dispersed titanium oxide catalysts promotes the charge separation which leads to an increase in the formation of CH4 in place of CH3OH formation. 相似文献
139.
The criteria for the mode selections in multiple-stripe lasers are presented. It is shown that the couplings of the higher-order modes of each stripe, which constitute the multiple-stripe laser, play important roles in the mode selections. Based on this analysis, a method for realizing 0° phase-shift mode oscillations is proposed. The method involves loss embedment in the outer unpumped region and the use of multiple stripes with fine center-to-center spacings. For the realization of this scheme, a grating-incorporated channeled-substrate planar (GICSP) laser is proposed and is fabricated. It is demonstrated that the 180° phase-shift mode is completely suppressed with this scheme. Single-longitudinal mode oscillations of well-defined index-guided 0° modes are observed for wide-channel CSP lasers. 相似文献
140.
In this paper, the synthesis and solid-state structures of β-alkyl-substituted dipyrrolyldiketone BF2 complexes are discussed; these complexes can function as π-conjugated acyclic anion receptors (“molecular flippers”) and are potential building subunits of anion-responsive π-conjugated oligomers or polymers. Modes of the solid-state assemblies in these complexes determined by performing single-crystal X-ray analysis are found to depend on the lengths of the alkyl chains at the β-positions. A β-methyl-substituted receptor has a highly planar structure, which efficiently forms stacking assemblies in the core π-plane in the solid state, while a β-ethyl-substituted receptor shows no stacking assemblies due to the presence of bulky ethyl moieties, which form only dimeric structures by hydrogen bonding. β-Alkyl-substituted anion receptors can be used not only as monomer units of stimuli-responsive polymeric macromolecules but also as components of solid-state electronic materials. 相似文献