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1.
Laboratory-scale and parametric experiments of SO2 and NOx removal from the simulated combustion gas by pulsed corona discharge have been performed by changing the combustion gas composition and temperature, the electrode configuration of plasma reactor, and the polarity of high-voltage electrode. The following results are obtained: 1) the higher the concentration of H2O and O2, the higher the efficiency of desulfurization and denitrification at the same specific input; 2) the pulsed corona discharge with a voltage pulsewidth as short as 200 ns of negative polarity shows the possibility to attain almost 90 percent deSOx and deNOx efficiency at the specific discharge input of 20 J/g, which is almost the same as the specific input in the electron-beam process; 3) the deNOx characteristics show a little temperature dependence in the range of 70 to 130°C, but the deSOx efficiency increases rapidly in the temperature region below 100°C suggesting the thermochemical dependence of deSOx reaction; 4) when desulfurization and denitrification proceed, the white dendritic powder deposits on the plasma reactor whose composition is identified to be 49 mol% (NH4)2SO4 and 47 mol% of 2NH4NO3 · (NH4)2SO4, and the ratio of SO2, NO and NH3 of the deposit is almost equal to that of supplied gas.  相似文献   
2.
Bioactive glass-ceramics toughened by tetragonal zirconia polycrystal (TZP) were prepared by hot-pressing mixed powders of the MgO-CaO-P2O5-SiO2 glass and TZP containing 20 to 80% alumina. The bending strength and the fracture toughness of the composite materials were improved compared with those of the material without TZP. These composites showed high bending strengths (400 to 500MPa) and high fracture toughness ( 2.8MPa m1/2). The existence of a crack deflection mechanism was observed by scanning electron microscopy. After soaking in simulated physiological solution at 100 °C, no phase transformation from tetragonal to monoclinic of TZP in the composites and no degradation in bending strength occurred.  相似文献   
3.
Growing evidence suggests that the gradual transformation of visuomotor association drives a distinct learning process from abrupt transformation in humans. In the current study, we developed a novel omnidirectional visuomotor transformation paradigm to study details of such difference in more realistic environment than conventional experimental systems. Participants were asked to perform a repetitive three-dimensional (3D) arm-reaching task to a target on a front touch panel, wearing a video see-through head-mounted device that displayed a rotating view of surrounding images. In the abrupt condition, the images were rotated by 20°; in the gradual condition, the rotation was increased in a stepwise-manner from 0° to 20°. In both conditions, pointing errors were decreased after adaptation. Further, although the aftereffect of adaptation was not different between conditions, the speed of decay of the aftereffect, which was quantified by an exponential fit, was slower in the gradual condition, suggesting longer-lasting aftereffects for the gradual shift.  相似文献   
4.
The effect of phosphorus ions on the proton conductivity was examined for the sol–gel-derived glasses. The porous glasses were prepared through hydrolysis of PO(OCH3)3 and Si(OC2H5)4, in which the phosphorus ions consisted of the POH bonds and were dissolved into the silica matrix without any P-O-Si bond. The electrical conductivity increased in a humid atmosphere and reached ∼30 mS/cm at 50°C under 70% RH. High conductivity is achieved by both the POH bonds and the molecular water bonded to the POH bonds. The conductivity increased with a change in humidity from 40% to 80% RH. The phosphorus ions were selectively dissolved in water, resulting in a lower conductivity.  相似文献   
5.
The block copolymers consisting of 2,7-dimethoxycarbazole- and oxadiazole-containing segments as hole and electron transporting units, respectively, were synthesized by NMRP manner. OLED devices were fabricated using block copolymer, random copolymer, and polymer blend for matrix of the emitting layer with Ir(ppy)3 as a phosphorescent dopant in order to investigate morphological effect on the performance. From the finding that the block copolymer system overwhelmed the others in EQE, we assumed that a morphology with dimethoxycarbazole units assembled to the surface of PEDOT:PSS played a considerable role for effective recombination of charges as well as sufficient charge injection into the emitting layer.  相似文献   
6.
BACKGROUND: Positron emission tomography (PET) allows the measurement of benzodiazepine-gamma-aminobutyric acidA (GABA(A)) receptor kinetics. We employed flumazenil radiolabeled with carbon 11, a radioligand that labels the benzodiazepine site on the GABA(A) receptor, and fully quantitative, high-sensitivity PET to test the hypothesis that central benzodiazepine site binding is decreased in medication-free patients with panic disorder. METHODS: We compared 7 patients with panic disorder who had been off medication for at least 6 months and who had never abused alcohol with 8 healthy controls. The resulting parametric voxel-by-voxel maps were analyzed by voxel-based and region of interest-based methods using both parametric and nonparametric statistics. RESULTS: The major finding was that there is a global reduction in benzodiazepine site binding throughout the brain in patients with panic disorder compared with controls. There were sex differences in the 2 samples, but a separate analysis excluding women led to the same conclusions. In addition, the loci with the largest regional decrease in binding (right orbitofrontal cortex and right insula) were areas thought to be essential in the central mediation of anxiety. CONCLUSION: These results must be considered preliminary but are congruous with previous clinical psychopharmacologic evidence of involvement of the benzodiazepine-GABA(A) receptor and demonstrate that decreased flumazenil binding at this site may underlie panic disorder.  相似文献   
7.
针对变压器油中水分检测的非线性、耦合性和时变性,提出了一种基于自适应模糊神经网络的变压器油中水分含量的检测方法。  相似文献   
8.
Ruthenium(II) complexes by introducing phenylene–ethynylene subunit into a tpy (tpy=2,2′:6′,2″-terpyridine) ligand were newly synthesized, and their photophysical and photochemical properties were characterized. The molar extinction coefficients of these dyes were larger than that of black dye. The photovoltaic performances of the solar cells based on these synthesizing dyes were investigated under AM 1.5 irradiation (100 mW cm?2). The conversion efficiencies of 1a and 1b were 5.7% and 2.4%, respectively.  相似文献   
9.
A new ruthenium(II)–polypyridine complex (1) having a 2,6-bis(4-carboxyquinolin-2-yl)pyridine ligand was synthesized as a sensitizer for dye-sensitized solar cells (DSCs). This complex exhibited remarkable light-harvesting properties in the near-IR region. DSCs sensitized with 1 showed a 35% incident photon-to-current conversion efficiency (IPCE) at 900 nm.  相似文献   
10.
A human dose response model for Escherichia coli O157 would enable prediction of risk of infection to humans following exposure from either foodborne or environmental pathways. However, due to the severe nature of the disease, volunteer human dose response studies cannot be carried out. Surrogate models from Shigella fed to humans and E. coli O157 to rabbits have been utilised but are significantly different to one another. In addition data obtained by animal exposure may not be representative for human beings. An alternative approach to generating and validating a dose response model is to use quantitative data obtained from actual human outbreaks. This work collates outbreak data obtained from global sources and these are fitted using exponential and beta-Poisson models. The best fitting model was found to be the beta-Poisson model using a beta-binomial likelihood and the authors favour the exact version of this model. The confidence levels in this model encompass a previously published Shigella dose response model. The potential incorporation of this model into QMRAs is discussed together with applications of the model to help explain foodborne outbreaks.  相似文献   
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