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991.
Gold nano-rod array membranes (Au-NRM) were prepared by modification of the template method. A simple two-electrode device was assembled by holding an electrolyte solution between the Au-NRM and a transparent electrode. Small reflectance changes (less than 2%) in the visible band were induced on the Au-NRM surface by applying a DC voltage to the device. These changes could be visually observed. It was found based on a further evaluation that the reflectance changes responded very fast (less than 100 ms) to the DC voltage application, and were stable during the switching repetition (over 5000 times). When the cyclic scanning of the applied voltage to the device was carried out between -1.5 V and +1.5 V, the reflectance changes were increased over +1.0 V (-1.0 V). It was suggested from these experimental results that the reflectance changes were attributed to the surface oxidation and the deformation or mechanical motion of the Au nano-rod. 相似文献
992.
993.
Study of Substrate Preheating on Flattening Behavior of Thermal-Sprayed Copper Particles 总被引:2,自引:0,他引:2
In this study, the effect of substrate preheating on flattening behavior of thermal-sprayed particles was systematically investigated.
A part of mirror-polished AISI304 substrates were preheated to 573 and 773 K for 10 min, and then exposed to an air atmosphere
for different durations of up to 48 h, respectively. Contact angle of water droplet was measured on the substrate under designated
conditions. It was found that the contact angle increased gradually with the increase of substrate duration after preheating.
Moreover, smaller contact angle was maintained on the substrate with higher preheating temperature. Commercially available
Cu powders were thermally sprayed onto the substrates with the same thermal treatment history as contact angle measurement
using atmospheric plasma-spray technique. The splat shape had a transitional changing tendency from a splash splat to a disk
one on the substrate with a short duration after preheating, while reappearance of splash splat with the increase of duration
was confirmed. In general, wetting of substrate surface by molten particles may dominate the flattening behavior of thermal-sprayed
particles. The occurrence of desorption of adsorbed gas/condensation caused by substrate preheating likely provides good wetting.
On the other hand, the poor wetting may be attributed to the re-adsorption of gas/condensation on the substrate surface with
the increase of duration. In addition, the shear adhesion strength of coating fabricated on blasted AISI304 substrate was
enhanced on the once-heated substrate, but weakened with the increase of duration. The changing tendency of the coating adhesion
strength and the wetting of substrate by droplet corresponded quite well with each other. 相似文献
994.
Naoomi Yamada Taro Hitosugi Ngoc Lam Huong Hoang Shoichiro Nakao Yasushi Hirose Toshihiro Shimada Tetsuya Hasegawa 《Thin solid films》2010,518(11):3101-3104
Transparent conducting Nb-doped anatase TiO2 (TNO) epitaxial films were sputtered from TiO2-, Ti2O3-, and Ti-based targets at various oxygen partial pressures (Po2). Using the TiO2- and Ti2O3-based targets, highly conductive films showing a resistivity (ρ) of ~ 3 × 10− 4 Ω cm could be formed without postdeposition treatment. In the case of the TNO films formed from the Ti-based target, reductive annealing had to be carried out at a temperature of 600 °C to achieve similar resistivity values. Thus, the use of oxide targets is preferable to obtain as-grown transparent conducting TNO films. In particular, the Ti2O3-based target is practically advantageous, because it offers a wide range of optimal Po2 values at which ρ values of the order of 10− 4 Ω cm are achievable. 相似文献
995.
In this study, natural agarose and agar polysaccharides were successfully developed to novel fibrous form for the first time via wet-spinning. Dimethyl sulfoxide (DMSO)/H2O = 9:1(v/v) mixture was used as an appropriate solvent which was amenable to the wet-spinning process that produced continuous agarose and agar fibers in ethanol coagulation bath. Results of SEM investigation, swelling ratio and tensile test suggested that the smooth and homogeneous agarose fibers had considerable water swelling capacity (400-500%) and tensile strength (30-50 MPa). The agar fiber showed better water swelling capacity than the agarose fiber; however the existence of agaropectin leads to its flexibility flaws. These results demonstrate that the agarose fiber fabricated in this study is a good candidate material for wound-dressing applications. 相似文献
996.
Hidetaka Konno Teruhiko Ito Mariko Ushiro Koji Fushimi Kazuhisa Azumi 《Journal of power sources》2010,195(6):1739-123
The B/C/N composites were synthesized by a very simple method, that is, carbonization at HTT = 800-1200 °C of the precursor prepared by drying a solution mixture of polyacrylamide and boric acid, followed by boiling in water to remove borate by-products. The amount of insoluble B species in the composite increased linearly from 4.8 to 18.6 mass% with raising HTT. The XRD and FT-IR revealed that turbostratic h-BN started to form at around 1000 °C as a by-product. By XPS, major B and N components in the composite were B-N bond, C-B-O type B, pyridinic N, pyrrolic N, and quaternary N. A fraction for B-N bond including h-BN in the total B or N components increased with raising HTT and it exceeded 50 at% between 900 and 1000 °C. It was suggested that in the composites formed at HTT > 1000 °C the amounts of h-BN increased, leading to reduction in other B and N components. The SBET was almost unchanged up to 1000 °C, 410-420 m2 g−1. Large and broad redox peaks arisen from plural reactions appeared in the cyclic voltammogram (CV) measured in 1 mol dm−3 H2SO4 for the composites formed at HTT ≤ 1000 °C. These peaks disappeared in 1 mol dm−3 solutions of Na2SO4 and Li2SO4. By comparing CV with that for C/N composite formed from PAA by the MgO template method, the pseudo-capacitance owing to reactions of B-N and C-B-O components with protons was found to be added to commonly observed pseudo-capacitance for nitrogen-doped carbons. The capacitances for the composites formed at 850-950 °C exceeded 300 F g−1 at 2 mV s−1 in the acid electrolyte and the retention at 50 mV s−1 was 78-80%. The shape of CV in the neutral electrolytes was trapezoid and the current density increased with lowering potential, suggesting adsorption and desorption of Na+ and Li+ ions. This was considered to be due to doped nitrogen, indicating the development of pseudo-capacitance. The capacitance per SBET was 0.33-0.74 F m−2 and 0.17-0.32 F m−2, larger for lower HTT, in the acid and neutral electrolytes, respectively. 相似文献
997.
998.
Marina Tišma Anita Jurić Ana Bucić‐Kojić Mario Panjičko Mirela Planinić 《Journal of the Institute of Brewing》2018,124(2):182-186
Brewers’ spent grain (BSG) is the main solid by‐product of the brewing process and is typically disposed of as cattle feed. In this study, BSG was evaluated as a substrate for the production of polyphenols and the lignin‐degrading enzyme laccase using fungal solid‐state fermentation by Trametes versicolor. Laccases are finding increasing applications in the food industry and polyphenols have benefits for human health. After 14 days of fermentation with T. versicolor, there was a 3.4‐fold increase in the extraction of total polyphenols compared with untreated BSG. Using BSG as the sole source of carbon and nitrogen, maximum laccase activity was achieved after seven days of treatment with an activity of 560 U/L. Based on these results, BSG is suggested to be a good lignocellulose waste material to produce value‐added products such as the enzyme laccase and polyphenols. Copyright © 2018 The Institute of Brewing & Distilling 相似文献
999.
Momo Takada Toshihiro Yamada Teruhiko Takahara Satoru Endo Kenichi Tanaka Tsuyoshi Kajimoto 《Journal of Nuclear Science and Technology》2017,54(4):452-458
Downward migration of 137Cs in soils was studied in three mixed deciduous forests c.a. 40 km northwest of the Fukushima Daiichi Nuclear power plant (FDNPP), Japan. We selected three different types of forest regarding to environmental condition such as slope inclinations and snow coverage conditions at the time of deposition. We examined temporal changes in the vertical distribution of 137Cs from litter layers to 10 cm soil depth for two years (2.3 to 4.3 years after the FDNPP accident in 2011). At all three study sites, the 137Cs in the litter layer had largely migrated to surface soil by 2013. After 2014, about 80% of the 137Cs in forest soils (litter layer to 10 cm soil depth) remained within 0–5 cm soil layer. The vertical distribution had not changed substantially since 2014, suggesting that changes to the downward migration rates of 137Cs in soils drastically decreased with time. In addition, small amounts of migrating 137Cs could not be detected by the present method because there was a large spatial variation in the distribution of soil 137Cs. The results showed similar patterns of soil 137Cs distribution among the three study sites although there were differences in the environmental conditions. 相似文献
1000.
Akihiro Ishimi Kozo Katsuyama Koji Maeda Hirotaka Furuya 《Journal of Nuclear Science and Technology》2017,54(11):1274-1276
Two- and three-dimensional images were obtained by X-ray CT in the reaction product between zircaloy-2 cladding tube and MOX fuel. The gamma-ray intensity distributions in the same specimen were also obtained by gamma-ray measurements of two fission products (Cs-137 and Eu-154) and one neutron-activated nuclide (Co-60). The average values of the fuel density (about 10.5 g/cm3) and the cladding density (about 6.55 g/cm3) were obtained in the metallic phase region by evaluation of the density distributions on two-dimensional X-ray CT images. The distributions of the crushed fuel pellet and the pores were also clearly observed in the three-dimensional X-ray CT images. The following results were found from the gamma-ray measurement. First, Cs-137 was observed in the unreacted fuel region and the pore region in the metallic phase region. Second, Eu-154 was widely distributed to all regions. Finally, Co-60 was confirmed only in the metallic phase region. 相似文献