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311.
Aligned ZnO nanorods were synthesized by a simple hydrothermal method without calcination. A seed layer of zinc acetate (ZnAc2)/sodium dodecyle sulfate (SDS) nanocomposite was used for nucleation of ZnO nanorods. First, a ZnAc2/SDS composite was deposited on a Si substrate by spin-coating. And then, ZnO nanorods were grown under hydrothermal conditions at 90 °C. ZnO crystals were grown in the direction of c-axis perpendicular to the surface of the Si substrate. However, nucleation did not occur on the substrate of a ZnAc2 seed layer without SDS, indicating that the presence of the ZnAc2/SDS seed enhanced the nucleation of ZnO crystals. These results show that high dispersion of ZnAc2 in the nanocomposite effectively assists a nucleation of ZnO crystals. 相似文献
312.
A lanthanum titanium oxynitride (LaTiO2N) electrode was studied as a visible-light driven photoelectrode for water splitting. The electrode was prepared by casting a LaTiO2N powder on a fluorine-doped tin oxide glass substrate, followed by calcination under dinitrogen. The as-prepared electrode exhibited an anodic photocurrent based on water oxidation under visible-light irradiation (λ > 420 nm) in an electrolyte (Na2SO4) solution. This current was increased by post-treatment with titanium(IV) chloride (TiCl4) solution. Scanning electron microscopy and X-ray photoelectron spectroscopy revealed that the titanium species introduced by the post-treatment were titanium oxide, and that they were embedded within LaTiO2N particles. Resistance measurements of LaTiO2N electrodes suggested that the increase in the electrode photocurrent after TiCl4 treatment was due to the improvement of inter-particle electron transfer in the LaTiO2N thin film. 相似文献
313.
Generation of Anode Spot in Low‐Current DC Vacuum Arcs by the Effect of Embedded Magnet in the Anode
Kazuki Kobayashi W. M. R. R. Wanninayake Takeshi Yanagidaira Naoyuki Sato Koichi Tsuruta 《IEEJ Transactions on Electrical and Electronic Engineering》2008,3(2):249-251
Experiments were conducted with the aim of keeping low‐current DC vacuum arcs stable. A permanent columnar magnet was embedded in the anode and a permanent disk‐shaped magnet was arranged behind the anode. As result, the arc plasma is strongly constricted to a column and a light emitting point appeared on the anode surface. Generation of the anode spot was confirmed by detecting anode metal vapor and ions using mass and spectroscopic analyses under low‐current arcs of less than 20 A. Copyright © 2008 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
314.
The aim of this study was to assess the efficacy of a novel water-soluble phytostanol anolog, disodium ascorbyl phytostanyl
phosphate (DAPP), on plasma lipid levels and red blood cell fragility in hamsters fed atherogenic diets. For 4 wk, 50 male
Golden Syrian hamsters were fed a semipurified diet without added cholesterol (noncholesterol, group 1), or a semipurified
diet with 0.25% cholesterol (cholesterol-control, group 2). Groups 3–5 were fed the cholesterol-control diet with an addition
of 1% phytostanols (diet 3), 0.71% DAPP (DAPP 0.7%, diet 4), or 1.43% DAPP (DAPP 1.4%, diet 5). Diets 4 and 5 provided 0.5
and 1% phytostanols, respectively. Supplementation of 0.71 and 1.43% DAPP decreased plasma total cholesterol concentrations
by 34 (P<0.001) and 46% (P<0.001), respectively, in comparison with the cholesterol-control group, whereas free stanols reduced (P=0.007) plasma cholesterol concentrations by 14%. Similarly, non-HDL-cholesterol concentrations were reduced by 39 (P<0.001) and 54% (P<0.001) in hamsters supplemented with DAPP 0.7% and DAPP 1.4%, respectively, relative to the cholesterol-control group. The
hypocholesterolemic effect of DAPP 1.4% was threefold stronger than that of free stanols. In hamsters supplemented with DAPP
1.4%, plasma TG concentrations were 45% lower (P=0.018) than in cholesterol-control-fed hamsters, whereas no such beneficial effect was observed in the free stanol group.
Erythrocyte fragility was unaffected by DAPP or free phytostanols. Results of the current study demonstrate that DAPP lowers
cholesterol more efficiently than free stanols, without an adverse effect on erythrocyte fragility in hamsters. 相似文献
315.
Satoshi Ogasawara Naoyuki Yamagishi Hiroyuki Totuka Hirofumi Akagi 《Electrical Engineering in Japan》1992,112(5):133-142
In general, diode rectifiers with electrolytic capacitors on the dc side have been used as dc power supplies for voltage source inverters. This type of rectifiers, however, causes many problems such as poor power factor and harmonics. Recently, voltage source PWM rectifier-inverters have been studied to provide the following advantages; (1) harmonic-free on both ac sides; (2) unity power factor on the input ac side; (3) power flow of either direction or power regeneration; (4) reduction of the dc capacitor. It is, however, difficult for a conventional one to regulate the capacitor voltage on transient states because of having only a voltage feed-back loop. This paper describes a voltage source PWM rectifier-inverter with feed-forward control of instantaneous power. Based on the pq theory, the instantaneous power which is calculated in the control circuit of the inverter is fed forward to the control circuit of the rectifier. The feed-forward control of instantaneous power makes a great contribution to sufficiently suppress voltage fluctuation of the dc capacitor on transient states. Transient characteristics are discussed and some interesting experimental results of a laboratory model are shown. 相似文献
316.
The physical properties and characteristics of unburned alumina-carbon refractories with added spherical alumina particles were investigated. The strength of the refractories was decreased whereas the packing density, erosion resistance and thermal shock resistance were improved by the addition of the spherical alumina particles. Based on these results, the lower nozzle of the sliding nozzle for continuous casting has been made of alumina-carbon refractories with added spherical alumina particles. The lower nozzle has shown uniform structure and reduced incidence of crack formation caused by thermal stress arising during casting. Accordingly, the durability of the lower nozzle has been considerably increased. 相似文献
317.
Taguchi T Saito H Iwasashi M Sakane M Kakinoki S Ochiai N Tanaka J 《Journal of nanoscience and nanotechnology》2007,7(3):742-747
A novel glue consisting of human serum albumin (HSA) and citric acid derivative (CAD) was developed where the glue is named as CAD-A glue. In this adhesive, CAD works as a crosslinking reagent of HSA. For preparing crosslinking reagent CAD, using citric acid as a starting material, three carboxyl groups of a citric acid were modified with N-hydroxysuccinimide in the presence of 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide hydrochloride. From 1H-NMR spectrum, CAD with three active ester groups in a molecule was successfully synthesized with a high yield (more than 80%). The boding time of CAD-A glue to collagen-based casing was saturated within 15 minutes. The bonding strength of this glue to collagen-based casings increased with increasing of HSA concentration. The maximum bonding strength of CAD-A glue was a slightly low level compared to the bonding strength of cyanoacrylate adhesive and was 9 times higher than that of fibrin glue. The CAD-A glue showed excellent biocompatibility and high ability of wound closure similar to that of cyanoacrylate-based adhesive when glues were applied to the mouse skin. These results suggested that this developed adhesive had both tissue compatibility and bonding strength for use in clinical field. 相似文献
318.
This paper presents a new method of unbalanced load flow calculation to improve complexity by the method of advanced symmetrical coordinates. Usually, the electric power system has been calculated only by the positive phase sequence component on the assumption that three‐phase transmission lines and loads are balanced. However, many ultrahigh‐voltage transmission lines are not transposed, and therefore mutual inductances cause negative sequence currents in the trunk transmission system. Negative sequence currents cause heating of generators and transformers, and therefore the three‐phase sequence component should be calculated accurately. We examined the fast computation and good convergence performance of unbalanced load flow calculation by models of three‐phase transmission lines, transformers, and loads. The proposed method is not the phase coordinate system but the method of symmetrical coordinates. This technique decreases numerical complexity by the use of a simplified Jacobian matrix. The convergence performance of this method is inferior to that of the usual Newton–Raphson method. As a consequence, the problem of poor convergence performance is alleviated by a technique for the newly developed deceleration Newton method. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 174(1): 17–24, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21034 相似文献
319.
Sato N Ishii K Satoh A Tanaka Y Hidaka T Nagaoka N 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2005,46(6):298-304
Fifty-two samples of broiled eels and broiled eel liver were analyzed for total mercury (total Hg) and methyl mercury. The mean concentrations of total Hg in broiled eels and broiled eel liver were 0.21 ppm and 0.10 ppm, respectively. Meanwhile, the mean concentrations of methyl mercury in broiled eels and broiled eel liver were 0.085 ppm and 0.039 ppm, respectively. The rate of methyl mercury to total Hg mainly ranged from 60 to 80% in broiled eels and from 35 to 65% in broiled eel liver. The total Hg concentrations of 2 samples of broiled eels and one sample of broiled eel liver exceeded the provisional regulation limit (0.4 ppm) of total Hg in fish in Japan. In these samples, the rates of methyl mercury to total Hg were lower than 20%. The muscles and the skin of broiled eels were measured separately. The ratios of skin to muscle concentration of total Hg and methyl mercury were mainly in the range from 1/10 to 1/4. The mean intakes of total Hg from broiled eels and broiled eel liver per individual were 24.6 microg and 3.1 microg, respectively. The mean intakes of methyl mercury from broiled eels and broiled eel liver per individual were 10.4 microg and 1.2 microg, respectively. 相似文献
320.
Nobuyuki?KosakaEmail author Yasuhiro?Fujiwara Tetsuji?Kurokawa Tsuyoshi?Matsuda Masayuki?Kanamoto Naoyuki?Takei Kenji?Takata Jin?Takahashi Yoshio?Yoshida Hirohiko?Kimura 《Magma (New York, N.Y.)》2018,31(4):577-584