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71.
A technique of calculating the frequency bias of an electric power system from frequency fluctuation data and total output power is described. An evaluation method for testing the calculations by the new method is developed. The results are in good agreement with estimates based on generator speed regulation but the method gives an excessively high figure for the load frequency bias.  相似文献   
72.
The emissivity of chlorinated polyethylene containing varying amounts of combined chlorine has been investigated. It was found that the emissivity of these compounds increases significantly with increase in chlorination.  相似文献   
73.
74.
To conduct proficiency testing for the analysis of pesticide residues in processed foods, fortified samples of retort curry and pancake were examined. In the case of retort curry, heating and mixing were necessary at the time of preparation to provide a homogenous analytical sample. A mixture of 4 carbamates and 11 organophosphorus pesticides was spiked and 14 of them showed consistent results in the samples. In the case of pancake, 10 kinds of pesticides were added to the pastry. The prepared pastry was them cooked. The relative concentrations of most of the pesticides in the pancake were not affected and all the pesticides showed consistent results in the samples. These results showed that the two tested samples were suitable for proficiency testing.  相似文献   
75.
Various Ti-oxide based photocatalysts such as the highly dispersed Ti-oxide species within zeolite frameworks, TiO2 nano-particles hybridized with hydrophobic zeolite adsorbents as well as visible light responsive TiO2 thin films have been successfully prepared. Characterization studies at the molecular level, such as X-ray absorption fine structure (XAFS) and photoluminescence (PL), revealed that the highly dispersed Ti-oxide species within the nano-spaces of zeolites possess a tetrahedral coordination and that they demonstrate unique and high performance for the photocatalytic decomposition of NOx and the photocatalytic reduction of CO2 with H2O. A high photocatalytic reactivity for the TiO2 semiconducting photocatalysts could be achieved by blending them with hydrophobic siliceous zeolites which was equal to the performance of TiO2 deposited with expensive Pt particles. The role of the siliceous zeolites can be described as a so-called “catch and release effect of organic compounds”, i.e., (i) the condensation of the reactants within the hydrophobic cavities of zeolites and; (ii) the efficient diffusion of the reactant onto the TiO2 photocatalytic sites. Furthermore, a novel photocatalytic system which can convert abundant solar energy into renewable H2 energy by the decomposition of H2O into H2 and O2 can also be achieved by using visible light responsive TiO2 thin film photocatalysts prepared by a RF-magnetron sputtering deposition method. The conversion efficiency of solar energy into H2 energy may be estimated at ca. 0.1% from the initial rate of H2 evolution.  相似文献   
76.
Morphologic control of Pt supported titanate nanotubes was attempted by the hydrothermal hot-pressing (HHP) technique in order to improve the handleability as a photocatalyst. The bulk of Pt-nanocrystal supported titanate nanotubes was successfully fabricated without the H2 reduction process by applying the HHP technique. The bulky Pt-nanocrystal supported titanate nanotubes possessed dense microstructures, significantly sharp distributions of mesopores, and high Brunauer–Emmett–Teller (BET) surface area. Furthermore, the bulky Pt-nanocrystal supported titanate nanotubes showed the photocatalytic degradation activities of 2-propanol aqueous solution under UV-light irradiation.  相似文献   
77.
The photocatalytic oxidation of gaseous acetaldehyde with O2 on commercial TiO2 nano-particles could be successfully enhanced by a simple mechanical blending with a high-silica mordenite (MOR) zeolite, the surface of which showed high hydrophobic properties. When the TiO2 nano-particles of ca. 5–20 wt% were mixed with the MOR zeolite powders in an agate mortar for only 5 min, the blended TiO2/MOR samples showed higher photocatalytic reactivity as compared to the pure TiO2 nano-particles. Since the high-silica zeolite powders are highly transparent in UV light regions, the incident UV light is effectively irradiated onto the whole part of the TiO2 nano-particles without any loss of light intensity. Furthermore, the siliceous MOR zeolite powders effectively adsorb the gaseous acetaldehyde molecules and supply them onto the surfaces of the blended TiO2 nano-particles, resulting in an enhancement of the photocatalytic reactivity.  相似文献   
78.
If both EVs (Electric Vehicles, includes plug‐in hybrid electric vehicles) and renewable energies spread in large quantities, it is possible to control the supply fluctuation of renewable energies using the storage battery of EVs. This research sought to show the charge load potential of EVs based on the state of the Japanese passenger car using traffic census results, etc. Furthermore, it tried to show the trend of the storage battery capacity according to time. From the estimated results: (1) the charge electricity of low and middle distance gets a majority of the total charge demand, (2) charge load changes according to time several times, and the minimum load is the number of gigawatt‐hours at early morning, (3) if night charge is assumed, the standby charge demand of noon will reach tens of gigawatt‐hours, it may have sufficient scale for supply fluctuation control of PVs. Although the present EV is not suitable for long‐distance running, these are expected to be 30 or less percent of the total charge demand. The estimated storage capacity potential in this research will not change numbers of times. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 182(3): 30–38, 2013; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22352  相似文献   
79.
2-Alkylcyclobutanones, such as 2-dodecylcyclobutanone and 2-tetradecylcyclobutanone, were analyzed to assess the irradiation history of irradiated meats or fish, and cooked foods with irradiated ingredients, which had been stored frozen for up to one year. The purpose of the study was to show that irradiated meats could be detected even after having been stored in the distribution system. 2-Alkylcyclobutanones showed a small decrease in irradiated raw meats that had been stored frozen for one year. Cooked foods, such as pancake and fried chicken made with irradiated eggs and chicken, respectively, contained detectable levels of 2-alkylcyclobutanones after storage frozen for one year. The 2-alkylcyclobutanones became undetectable in highly dried samples, such as feed for lab animals, during the same period.  相似文献   
80.
Novel bioreactor beads for simultaneous saccharification and fermentation (SSF) of lime-pretreated rice straw (RS) into ethanol were prepared. Genetically modified Saccharomyces cerevisiae cells expressing genes encoding xylose reductase, xylitol dehydrogenase, and xylulokinase were immobilized in calcium alginate beads containing inorganic lightweight filler particles to reduce specific gravity. For SSF experiments, the beads were floated in slurry composed of lime-pretreated RS and enzymes and incubated under CO2 atmosphere to reduce the pH for saccharification and fermentation. Following this reaction, beads were readily picked up from the upper part of the slurry and were directly transferred to the next vessel with slurry. After 240 h of incubation, ethanol production by the beads was equivalent to that by free cells, a trend that was repeated in nine additional runs, with slightly improved ethanol yields. Slurry with pre-saccharified lime-pretreated RS was subjected to SSF with floating beads for 168 h. Although higher cell concentrations in beads resulted in more rapid initial ethanol production rates, with negligible diauxic behavior for glucose and xylose utilization, no improvement in the ethanol yield was observed. A fermentor-scale SSF experiment with floating beads was successfully performed twice, with repeated use of the beads, resulting in the production of 40.0 and 39.7 g/L ethanol. There was no decomposition of the beads during agitation at 60 rpm. Thus, this bioreactor enables reuse of yeast cells for efficient ethanol production by SSF of lignocellulosic feedstock, without the need for instruments for centrifugation or filtration of whole slurry.  相似文献   
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