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排序方式: 共有573条查询结果,搜索用时 250 毫秒
101.
Multiple evaluations of the removal of pollutants in road runoff by soil infiltration 总被引:2,自引:0,他引:2
Murakami M Sato N Anegawa A Nakada N Harada A Komatsu T Takada H Tanaka H Ono Y Furumai H 《Water research》2008,42(10-11):2745-2755
Groundwater replenishment by infiltration of road runoff is expected to be a promising option for ensuring a sustainable urban water cycle. In this study, we performed a soil infiltration column test using artificial road runoff equivalent to approximately 11-12 years of rainfall to evaluate the removal of pollutants by using various chemical analyses and bioassay tests. These results indicated that soil infiltration treatment works effectively to remove most of the pollutants such as organic matter (chemical oxygen demand (CODMn) and dissolved organic carbon (DOC)), P species, polycyclic aromatic hydrocarbons (PAHs), numerous heavy metals and oestrogenic activities. Bioassay tests, including algal growth inhibition test, Microtox and mutagen formation potential (MFP) test, also revealed effective removal of toxicities by the soils. However, limited amounts of NO3, Mn, Ni, alkaline earth metals, perfluorooctane sulphonate (PFOS) and perfluorooctane sulphonamide (FOSA) were removed by the soils and they possibly reach the groundwater and cause contamination. 相似文献
102.
Spot-size converter integrated semiconductor optical amplifiers foroptical gate applications 总被引:1,自引:0,他引:1
Kitamura S. Hatakeyama H. Hamamoto K. Sasaki T. Komatsu K. Yamaguchi M. 《Quantum Electronics, IEEE Journal of》1999,35(7):1067-1074
A spot-size converter integrated semiconductor optical amplifier (SSC-SOA) was developed as a gate element in an optical switch matrix for photonic switching applications. By a selective metal-organic vapor phase epitaxy technique, a bulk InGaAsP stripe, including an active region and thickness tapered SSCs, was grown. Wavelength composition of the stripe, strain on the stripe, and electrode coverage above the SSC region were optimized. As a result, gate operation for fiber-to-fiber gain of 0 dB was achieved at a low injection current of 30 mA, and the polarization dependence of the gain was eliminated as well 相似文献
103.
Toshiyuki Nagata Kentaro Minami Masatatsu Yamamoto Tsubasa Hiraki Masashi Idogawa Katsumi Fujimoto Shun Kageyama Kazuhiro Tabata Kohichi Kawahara Kazuhiro Ueda Ryuji Ikeda Yukio Kato Masaaki Komatsu Akihide Tanimoto Tatsuhiko Furukawa Masami Sato 《International journal of molecular sciences》2021,22(21)
104.
Tamikuni Komatsu 《应用聚合物科学杂志》1996,59(7):1137-1143
Strong adhesion in the superdrawn polyoxymethylene (POM) fiber/epoxy matrix system was achieved with surface treatments, 2H-hexafluoro-2-propanol (HFP) treatment, and surface phenolation of the fiber. HFP produced micropits for mechanical interlocking with the matrix. Surface phenolation formed active layers leading to interfacial miscibility. © 1996 John Wiley & Sons, Inc. 相似文献
105.
Atomic resolution imaging using the high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) can be applied to analyze the atomic structures of materials directly. This technique provides incoherent Z-contrast with the atomic number of the constituent elements. In the present work, unique contrasts that make intuitively interpreting the HAADF-STEM image in double perovskite oxide La2CuSnO6 difficult were observed. Multislice simulation confirmed that this occurred as an effect of the channeling process of electrons in combination with the effect of Debye–Waller factors. This was confirmed because in the La2CuSnO6 crystal, two independent Sn atoms and four independent La atoms in the unit cell had different Debye–Waller factors, and the La columns consisted of pairs of columns with a small separation, whereas the Sn atoms were arranged straight. 相似文献
106.
Zhensu Zeng Seiji Kuroda Jin Kawakita Masayuki Komatsu Hidenori Era 《Journal of Thermal Spray Technology》2010,19(1-2):128-136
The oxidation behavior of iron binary powders with addition of Si (1, 4 wt.%) and B (1, 3 wt.%) and that of a Ni-Cr based alloy powder with Si (4.3 wt.%), B (3.0 wt.%), and C (0.8 wt.%) additions during atmosphere plasma spray (APS) have been investigated. Analysis of the chemical composition and phases of oxides in the captured in-flight particles and deposited coatings was carried out. The results show that the addition of Si and B to iron effectively reduced the oxygen contents in the coatings, especially during the in-flight period at higher particles temperature. Ni-Cr based alloy powder with Si, B, and C additions reduced the oxidation of the base alloys significantly. Preferential oxidation and subsequent vaporization of Si, B, and C from the surface of the sprayed particles are believed to play a major role in controlling oxidation in the APS process. 相似文献
107.
108.
Naomi Hirokawa Tsuyoshi Honma Takayuki Komatsu Yasuhiko Benino 《Journal of the American Ceramic Society》2008,91(7):2170-2175
A combination technique of Nd:YAG laser (wavelength: 1064 nm) irradiations and chemical etchings was applied to fabricate microsize U-shaped grooves on the surface of CuO-doped BaO–TiO2 –GeO2 glass, and chemical etching behaviors were examined by using a confocal scanning laser microscope. Continuous-wave Nd:YAG lasers with a power of 0.7–0.8 W were irradiated onto the glass surface and scanned at a speed of 10 μm/s, inducing structural modified lines with refractive index changes. The chemical etching rates for the refractive index changed lines in a nitric acid solution (1 N HNO3 ) were larger than those for the base glass (nonirradiated part). The etching profile was changed gradually from W-shaped to U-shaped grooves with increasing etching time. The sharp bending lines with an angle of 150° and the cross-linked lines were also smoothly etched. The U-shaped grooves with a surface covered by nonlinear optical Ba2 TiGe2 O8 crystals were formed by the crystallization of etched samples. This study proposes that the patterning of microchannels with optical functional surfaces is possible on the glass surface using the present technique. 相似文献
109.
Blue/DVD/CD compatible optical head 总被引:1,自引:0,他引:1
Compatibility with Digital Versatile Disc and Compact Disc has been demonstrated for two options of high-density optical disk systems using a blue laser diode. Option 1 (HD DVD) employs a 0.65 numerical aperture objective lens and a 0.6 mm thick protective layer disk, while Option 2 (Blu-ray Disc) employs a 0.85 numerical aperture objective lens and a 0.1 mm thick protective layer disk. An optical head has three laser diodes whose wavelengths are 405 nm, 660 nm, and 785 nm. A spherical aberration caused by the difference in the protective layer thickness of the disk is corrected by an objective lens magnification change, while the numerical aperture of the objective lens is controlled by a wavelength-selective aperture. Experimental results have shown that Option 1 is more preferable, but Option 2 is also acceptable from the viewpoint of the compatibility. 相似文献
110.
Shu Yin Masakazu Komatsu Bin Liu Ruixing Li Yuhua Wang Tsugio Sato 《Journal of Materials Science》2008,43(7):2240-2246
The TiO2−x
N
y
nanocrystals with beige color were prepared by homogeneous precipitation-solvothermal process in TiCl3-hexamethyleneamine-alcohol solutions with the addition of various surfactants, such as sodium dodecylbenzenesulfonate (SDBS),
n-hexadecylamine (HAD), and n-hexadecyltrimethylammonium chloride (HTAC) at 190 °C for 10 h. The phase composition, crystallinity, microstructure, specific
surface area, nitrogen doped amount, and photocatalytic activity of titania powders greatly changed depending on pH value
and other reaction conditions. The TiO2−x
N
y
powders prepared by solvothermal treatment with surfactant additives followed by calcination in air at 400 °C showed smaller
particle size, larger BET specific surface area and higher photocatalytic activity than those without surfactant. The TiO2−x
N
y
powders showed excellent visible-light absorption, thermal stability and photocatalytic activity for nitrogen monoxide destruction
under irradiation of both visible-light and UV-light irradiation. About 40% and 60% nitrogen monoxide could be continuously
removed with the residence time of 1.9 min by the TiO2−x
N
y
photocatalyst under irradiation of visible-light (λ > 510 nm) and UV-light (λ > 290 nm), respectively. 相似文献