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11.
Mercury oxidation by hydrochloric acid over the metal oxides supported by anatase type TiO2 catalysts, 1 wt.% MOx/TiO2 where M = V, Cr, Mn, Fe, Ni, Cu, and Mo, was investigated by the Hg0 oxidation and the NO reduction measurements both in the presence and absence of NH3. The catalysts were characterized by BET surface area measurement and Raman spectroscopy. The metal oxides added to the catalyst were observed to disperse well on the TiO2 surface. For all catalysts studied, the Hg0 oxidation by hydrochloric acid was confirmed to proceed. The activity of the catalysts was found to follow the trend MoO3 ~ V2O5 > Cr2O3 > Mn2O3 > Fe2O3 > CuO > NiO. The Hg0 oxidation activity of all catalysts was depressed considerably by adding NH3 to the reactant stream. This suggests that the metal oxide catalysts undergo the inhibition effect by NH3. The activity trend of the Hg0 oxidation in the presence of NH3 was different from that observed in its absence. A good correlation was found between the NO reduction and the Hg0 oxidation activities in the NH3 present condition. The catalyst having high NO reduction activity such as V2O5/TiO2 showed high Hg0 oxidation activity. The result obtained in this study suggests that the oxidation of Hg0 proceeds through the reaction mechanism, in which HCl competes for the active catalyst sites against NH3. NH3 adsorption may predominate over the adsorption of HCl in the presence of NH3.  相似文献   
12.
Abstract— Properties of a plasma‐display‐panel (PDP) like discharge were examined by emission and laser Thomson scattering (LTS) measurements. Emission measurements were performed using an intensified CCD camera. By varying several external parameters such as the amplitude of the input voltage, gas composition, and pressure, the influence of these parameters on the discharge behavior was studied. Results of emission measurements showed that they were in good agreement with similar emission measurements on real PDP cells. LTS measurements were performed for the striated PDP‐like discharge at a pressure of 100 Torr and the results showed clear modulations in both profiles of electron density and electron temperature.  相似文献   
13.
A full-color twisted-nematic type liquid crystal display (TN-LCD) of 1.4-in diagonal size driven by organic thin-film transistors (TFTs) has been fabricated. This TN-LCD has 80/spl times/80/spl times/3 (RGB) pixel arrays addressed by pentacene TFTs with a channel width of 50 /spl mu/m. The contact resistance between the pentacene film and the source/drain electrodes has been reduced by selecting the exposure condition of the photoresist in patterning the electrodes. In addition, a solution-processed passivation film with a novel structure, consisting of photosensitive polyvinylalcohol and organosiloxane glass resin, has been developed to protect the TFTs against degradation induced by integration with TN-LCD devices. Consequently, it has been confirmed that the organic-TFT-driven TN-LCD fabricated in this paper is capable of displaying full-color moving images at a resolution of 80 pixels per inch.  相似文献   
14.
In order to determine the superconducting gap structure of the borocarbide superconductor YNi2B2C, we have measured the angular variation of the c-axis thermal conductivity zz in magnetic field rotated within the ab-planes. A clear fourfold symmetry with narrow cusps was observed in the angular variation of zz . These results provide a strong evidence that the gap function has point nodes which are located along the a- and b-axes of the crystal.  相似文献   
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16.
To ascertain whether wild male turtles were influenced by environmental estrogens, we examined serum vitellogenin (VTG) levels of male Reeves' pond turtles (Chinemys reevesii) collected from four study sites (A-D) in Kyoto, Japan. Sites A-C, which were impacted by domestic or industrial wastewater and effluents from sewage treatment plants, were chosen as contaminated sites, and site D was intended as a reference site. This contaminated/reference site characterization was confirmed by measuring estrogenic activities of the water samples collected at each site for over a year. Serum VTG levels in the turtles were quantified by an enzyme-linked immunosorbent assay established previously. Estrogenic activities of the water samples were measured using a previously validated yeast two-hybrid assay and expressed as the estradiol-17beta equivalent. Estrogenic activity was observed at high levels at sites A-C, but was almost undetected at site D throughout the sampling period: the mean and range were 0.74 (<0.07-2.1), 0.52 (0.17-1.6), 1.7 (<0.07-7.3), and 0.07 (<0.07-0.62) ng/l at sites A-D, respectively. Significant differences were found only in site D versus sites A, B, and C. Therefore, site D and sites A-C were confirmed to be a reference site and contaminated ones, respectively. Overall, 320 male turtles were captured and examined. The majority of the turtles showed normal VTG values (0.10-0.74 microg/ml). Although only five turtles from sites A-C showed unusually high VTG values (1.1-5.9 microg/ml, nearly one order of magnitude higher than normal values but much lower than values in adult females), there was no significant difference in the incidence of these high values between sites A-C and site D. Moreover, among the five turtles, one turtle was captured again 2 months later, but its VTG value dropped to the normal level. The unusually high VTG values may therefore be transient elevation caused by incidental and/or individually specific agents. Excluding the unusually high values, the mean serum VTG (accompanied with the range) was 0.22 (0.10-0.74), 0.27 (0.11-0.62), 0.27 (0.17-0.68), and 0.23 (0.10-0.57) microg/ml at sites A-D, respectively. There were no significant differences in the mean VTG values among sites A-D. Although it should be clarified how and why the unusually high VTG values occurred at sites A-C, our results suggested that wild male C. reevesii turtles would not be significantly affected by xenobiotic estrogens at environmentally relevant levels in terms of serum VTG elevation.  相似文献   
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18.
Electric power systems in Japan are composed of remote and distributed location of generators and loads mainly concentrated in large‐demand areas. The structures having long‐distance transmission tend to produce heavy power flow with increasing electric power demand. In addition, some independent power producers (IPP) and power producer and suppliers (PPS) are participating in the power generation business, which makes power system dynamics more complex. However, there was little observation as a whole power system. In this paper the authors present a global monitoring system of power system dynamics by using the synchronized phasor measurement of demand‐side outlets. Phasor Measurement Units (PMU) are synchronized based on the global positioning system (GPS). The purpose of this paper is to show oscillation characteristics and methods for processing original data obtained from PMU after certain power system disturbances triggered by accidents. This analysis resulted in the observation of the lowest and the second lowest frequency mode. The derivation of eigenvalue with the two‐degree‐of‐freedom model brings a monitoring of two oscillation modes. Signal processing based on wavelet analysis and simulation studies to illustrate the obtained phenomena are presented in detail. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 163(3): 10– 18, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20316  相似文献   
19.
The purpose of the present study was to develop an animal model of nicotine self-administration that more closely approximates the conditions of human nicotine use than do existing models. In most nicotine self-administration models, rats acquire self-administration during brief daily sessions in which rapid injections of a relatively high dose of the drug, 0.03 mg/kg, serve as the reinforcer. The present study examined nicotine self-administration in rats that acquired the behavior while having virtually unlimited access to injections of a relatively low dose of the drug; the rats did not have any prior operant training or shaping. Under these conditions, rats readily acquire nicotine self-administration at doses at least as low as 0.00375 mg/kg per injection, and they self-administer throughout the active portion of their light cycle. The daily nicotine intake of rats, which ranged from 0.18 to 1.38 mg/kg per day, appears to be comparable to that of human smokers.  相似文献   
20.
BACKGROUND/PURPOSE: Hirschsprung's disease (HD, HSCR) is one of the most common diseases in the field of pediatric surgery. It is well known that the aganglionic bowel is primarily a causative factor of dismotility of distal narrow segment. Recent studies have shown that mutations in endothelin-B receptor (EDNRB), endothelin-3, RET, glial cell line-derived neurotrophic factor (GDNF) genes are responsible for the occurrence of congenital aganglionosis. Here, the authors describe two new mutations of the EDNRB gene in Japanese patients with HD. RESULTS: One patient had a heterozygous point mutation at the splice donor site of intron 3, leading to premature termination of translation of EDNRB mRNA. Another patient has a heterozygous missense mutation (N1041) in exon 1, but the same mutation was found in two of 50 normal individuals, so the mutation may be a noncausative polymorphism of the EDNRB gene. CONCLUSION: These results provide further evidence that a spectrum of different mutations within the EDNRB gene are responsible for HD.  相似文献   
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