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71.
Takuya Kitabatake Tetsuo Uchikoshi Fumio Munakata Yoshio Sakka Naoto Hirosaki 《Journal of the European Ceramic Society》2012,32(7):1365-1369
The compaction of a Eu-doped Ca-α-SiAlON phosphor powder was performed by electrophoretic deposition (EPD). The effect on the adhesion and optical properties of the silica precursor as both a binder of the powder and a filler of the air voids were evaluated. The adhesion of the silica impregnated composite film to the silica glass substrate was characterized by the tape test. The improvement of the external quantum efficiency was confirmed from the PL spectra measurement after the silica impregnation. The temperature dependence of the external quantum efficiency was also investigated in order to discuss the advantage of using the silica precursor as a binder for high-brightness LED applications. 相似文献
72.
Yuya Tachibana Takuya Maeda Osamu Ito Yasukatsu Maeda Masao Kunioka 《International journal of molecular sciences》2009,10(8):3599-3615
We have developed a mulch sheet made by inflation molding of PLA, Ecoflex® and modified starch, which all have different biodegradabilities. A field test of use as an agricultural mulch sheet for mandarin oranges was carried out over two years. The mechanical properties of the mulch sheet were weakened with time during the field test, but the quality of the mandarin oranges increased, a result of the controlled degradation of the sheet. The most degradable modified starch degraded first, allowing control of the moisture on the soil. Accelerator mass spectroscopy was used for evaluation of the biomass carbon ratio. The biomass carbon ratio decreased by degradation of the biobased materials, PLA and modified starch in the mulch sheet. 相似文献
73.
Identifying network density and scale economies for Japanese water supply organizations 总被引:3,自引:0,他引:3
Within this analysis we determine the optimal size (that is, with the minimum average cost) of a water supply enterprise
and reconsider the matter of scale economies, using sample data from Japanese water supply organizations. After surveying
evidence from previous studies of scale economies in the water supply industry, we estimate cost functions with three different
cost models: the log-linear, translog and translog with a hedonic function. We obtain the result that economies of network
density do exist, but that there are slight diseconomies of scale at the sample mean point. The optimal size of a water supply
organization would be one supplying a population of approximately 766,000 people.
Received: 10 March 2000 / Accepted: 8 January 2001 相似文献
74.
75.
Takatoshi Akase Takuya Ryoke Hiromitsu Kozuka 《Journal of the American Ceramic Society》2009,92(9):1951-1958
Titania gel films were prepared from a coating solution with a starting mole ratio of Ti(OC3 H7 i )4 :H2 O:HNO3 :C2 H5 OH=1:1:0.2:30 on Si(100) wafers by spin coating, with and without sol–gel-derived, fired silica, and titania underlayers. In situ measurement was conducted on the in-plane stress in the titania gel films during heating up to 500°C at 5°C/min. Basically, for all the gel films, the in-plane, tensile stress increases once with increasing temperature, and then decreases around the temperature of crystallization. The increase in stress was thought to result from the capillary pressure due to solvent evaporation and from the densification of the coatings. The reduction in stress around the temperature of crystallization was ascribed to the accelerated atomic diffusion in the coatings and to the difference in thermal expansion coefficient between the coatings and the Si wafer. However, when the stress–temperature curves were examined more in detail, differences were found in the variation in stress, depending on the underlayers. Then, the question of how the underlayers could induce the crystallization and relax the strain in the coatings was discussed. 相似文献
76.
Smooth CuLa0.98Eu0.02O2 thin film has successfully been prepared by pulsed laser deposition method at room temperature. Crystal structure of the obtained film was almost same as that of CuLa0.98Eu0.02O2 polycrystalline ceramic. Orange luminescence with high intensity due to 5D0 – 7F0,1 transitions of Eu3+, which was an evidence of Eu3+ substitution for La3+ site in LaO6 octahedra with the inversion symmetry, was also observed in the obtained film. The optical band gap of CuLa0.98Eu0.02O2 was measured to be 2.85 eV from absorption spectroscopy. 相似文献
77.
William P. Linak C. Andrew Miller Joseph P. Wood Takuya Shinagawa Jong-Ik Yoo Dawn A. Santoianni 《Aerosol science and technology》2013,47(9):900-913
The potential use of sorbents to manage ultrafine ash aerosol emissions from residual oil combustion was investigated using a downfired 82 kW laboratory-scale refractory-lined combustor. The major constituents were vanadium (V), nickel (Ni), iron (Fe), and zinc (Zn). The overall ash content of residual oil is very low, resulting in total ash vaporization at 1725 K with appreciable vaporization occurring at temperatures as low as 1400 K. Therefore, the possibility of interactions between ash vapor and sorbent substrates exists. Kaolinite powder was injected at various locations in the combustor. Ash scavenging was determined from particle size distributions (PSDs) measured by a Scanning Mobility Particle Sizer. Impactor samples and X-ray fluorescence (XRF) analyses supported these data. Injection of kaolinite sorbent was able to capture up to 60% of all the ash in the residual fuel oil. However, captures of ~ 30% were more common when sorbent injection occurred downstream of the combustion zone, rather than with the combustion air into the main flame. Without sorbent addition, baseline measurements of the fly ash PSD and chemical composition indicate that under the practical combustion conditions examined here, essentially all of the metals contained in the residual oil form ultrafine particles (~0.1 μ m diameter). Theoretical calculations showed that coagulation between the oil ash nuclei and the kaolinite sorbent could account for, at most, 17% of the metal capture which was always less than that measured. The data suggest that kaolinite powders reactively capture a portion of the vapor phase metals. Mechanisms and rates still remain to be quantified. 相似文献
78.
Rolling process was carried out with extruded polypropylene as crystalline polymer at various rolling temperatures, and the rolling characteristics, cross‐section morphologies, and tensile properties were investigated. The rolling characteristics were evaluated by springback and dimensional change. The springback increased with increasing rolling temperature. The increment of length was larger than that of width because of the influence of uniaxial drawing by rotation of the rollers. Uniform morphologies were observed at a rolling ratio of 70% and a rolling temperature of 23°C. In contrast, molecular orientation near the surface was higher compared with the inner part when rolled at 70°C. Furthermore, micro spherulitic structures were observed near the surface where recrystallization occurred because of the rising temperature on the specimen surface by friction. Therefore, different morphologies appeared near the surface and in the inner part. Tensile strength was obtained for the rolling direction when rolled at 110°C lower than at other rolling temperatures. It was likely that the molecular orientation was decreased by increasing the springback when rolled at high temperature. POLYM. ENG. SCI., 53:2573–2581, 2013. ©2013 Society of Plastics Engineers 相似文献
79.
A self-assembled monolayer (SAM) of l-homocysteine (l-Hcy) formed on the surface of a gold-deposited gate of a field effect transistor (FET) was used to differentiate between enantiomers of amino acids, for which the formation of diastereomeric metal complexes is fundamental for chiral discrimination. Here, we focus our attention on the dependence of the FET response on the analyte amino acids, the central metal ions involved in complex formation, and the solution pH. Using the l-Hcy SAM-modified gate with added Cu(II), notable negative FET responses were enantioselectively observed for the l-enantiomers of alanine (Ala), phenylalanine, and tryptophan, whereas differences in the FET responses between enantiomers were negligible for asparagine and aspartic acid. Regarding the enantioselectivity for Ala, the addition of Cu(II) was demonstrated to show higher selectivity as compared to other metal ions such as Co(II) and Ni(II). Moreover, for the addition of l-Ala and Cu(II), a particularly strong negative FET response was observed at pH 5.5. 相似文献
80.
Md. Zaved Hossain Khan Takuya Nakanishi Shigeki Kuroiwa Yoichi Hoshi Tetsuya Osaka 《Electrochimica acta》2011,(24):8657
The effect of surface modification of indium tin oxide (ITO) electrode on its potential response to tryptophan was investigated for ITO substrates with different surface roughness. It was found that a small difference in surface roughness, between ∼1 and ∼2 nm of Ra evaluated by atomic force microscopy, affects the rest potential of ITO electrode in the electrolyte. A slight difference in In:Sn ratio at the near surface of the ITO substrates, measured by angle-resolved X-ray photoelectron spectrometry and Auger electron spectroscopy is remarkable, and considered to relate with surface roughness. Interestingly, successive modification of the ITO surface with aminopropylsilane and disuccinimidyl suberate, of which essentiality to the potential response to indole compounds we previously reported, improved the stability of the rest potential and enabled the electrodes to respond to tryptophan in case of specimens with Ra values ranging between ∼2 and ∼3 nm but not for those with Ra of ∼1 nm. It was suggested that there are optimum values of effective work function of ITO for specific potential response to tryptophan, which can be obtained by the successive modification of ITO surface. 相似文献