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排序方式: 共有537条查询结果,搜索用时 265 毫秒
51.
Seiji Yamashita Hideo Watanabe Takashi Shirai Masayoshi Fuji Minoru Takahashi 《Advanced Powder Technology》2011,22(2):271-276
We have successfully synthesized zinc oxide microrods perpendicularly oriented on hexagonal ZnO sheets by a simple heat treatment approach using LDH (layered double hydroxide) precursor in an aqueous solution. The synthesized ZnO microrods have an average diameter of 500 nm and length of 2–3 μm, and form highly-oriented array. In this work, the effect of heating temperature and time on morphology and orientation of ZnO microrods was studied experimentally and the formation mechanism was discussed in detail. Transformation from hexagonal precursor to ZnO microrods can be attributed to dissolution and re-precipitation of the precursor, which should be caused by its thermal unstability under heating temperature. 相似文献
52.
Fumitaka Goto Katsunori Shirai Masaya Ichimura 《Solar Energy Materials & Solar Cells》1998,50(1-4):147-153
Using the electrochemical deposition method, CdS thin films were deposited from acid solutions (pH = 2.5) containing CdS04 and Na2S203 on indium-oxide coated glass substrates. These films were annealed in N2, air, or O2 atmosphere at 200–500°C for 30 min. Photoluminescence spectra were measured at 77 K. For the films annealed in N2, the band edge emission became weaker and the luminescence due to defects shifted to longer wavelengths as the annealing temperature was raised above 300°C. However, for the films annealed in air or O2, the band edge emission was observed strongly irrespective of the annealing temperature and the luminescence due to defects was weak. Thus the O2 annealing is useful for the defects reduction. 相似文献
53.
Moriwaki H Takagi Y Tanaka M Tsuruho K Okitsu K Maeda Y 《Environmental science & technology》2005,39(9):3388-3392
Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are shown to be globally distributed, environmentally persistent, and bioaccumulative. Although the toxicities of these compounds were reported, the cleanup procedure from the environment is not developed because of their inertness. In this report the sonochemical degradations of PFOS and PFOA to the products through the fission of the perfluorocarbon chains were observed and the half-life times of the PFOS and PFOA degradations under an argon atmosphere determined to be 43 and 22 min, respectively. The shortening of perfluorocarbon chain of PFOS and PFOA leads to the lowering of the toxicity in view of the decrease of the persistence, and the technique would contribute to the remediation of the environmental pollution by these compounds. 相似文献
54.
Bae J. Nozokido T. Shirai H. Furuya K. Nishida T. Mizuno K. 《Quantum Electronics, IEEE Journal of》1989,25(7):1591-1594
A modified current pulsed Q (EMQ)-switched CO2 laser which is Q -switched by a mechanical beam chopper in combination with a pulsed discharge current is discussed. The laser produces a very stable output with a peak power greater than 1 kW at a repetition rate of 1000 p.p.s. for all transitions in the P and R branches of the CO2 spectrum. A CH3F laser pumped by the EMQ-switched laser produces 496 μm radiation in a 6.5 W peak, 100 ns pulses at 500 p.p.s. in the lowest loss EH11 mode 相似文献
55.
K Takeshita S Furui S Ban A Harasawa H Kohtake T Yamauchi Y Sasaki T Shirai Y Kikuchi 《Canadian Metallurgical Quarterly》1996,56(11):744-746
Helical computed tomography was performed with intravenous contrast material administration in ten patients with hepatic tumors (metastatic tumor, n = 6; hepatocellular carcinoma, n = 4). Maximum intensity projection (MIP) images of intrahepatic portal venous branches and hepatic veins, and shaded surface display (SSD) images of the hepatic tumors were reconstructed for each patient. The MIP image and SSD image were fitted to overlap on a single display to obtain three-dimensional (3-D) images showing both the hepatic vessels and hepatic tumors. Subsegmental localization of the tumors determined from the 3-D images proved to be correct in all of the six patients who received hepatic resection after examination. 3-D images seem to be useful for preoperative assessment of hepatic tumors. 相似文献
56.
T Fujimura S Hirose Y Jiang S Kodera H Ohmuro D Zhang Y Hamano H Ishida S Furukawa T Shirai 《Canadian Metallurgical Quarterly》1998,10(10):1467-1472
Gene(s) in the MHC of the NZW strain (H-2z) up-regulate(s) systemic lupus erythematosus (SLE) in (NZB x NZW) F1 mice. So far, two plausible mechanisms have been implicated: (i) unique mixed haplotype class II molecules formed in the F1 mice act as a restriction element for self-reactive T cells and (ii) a unique polymorphism in the H-2-linked NZW tumor necrosis factor (TNF)-alpha allele which down-regulates TNF-alpha is contributory. Because of the difficulty in dissecting these alleles within the H-2 complex, it has not been determined which is indeed the case. We addressed this issue by establishing three different H-2-congenic (NZB x NZW) F1 mice bearing distinct haplotypes at class II and TNF-alpha regions, i.e. (NZB x NZW) F1 (H-2d/z:A(d/u)E(d/u)TNF(d/z)), (NZB x NZW.PL) F1 (H-2(d/u):A(d/u)E(d/u)TNF(d/d)) and (NZB x NZW.H-2d) F1 (H-2(d/d):A(d/d)E(d/d)TNF(d/d)). Among these, only (NZB x NZW) F1 produced a markedly lower level of TNF-alpha, due to the unique NZW TNF-alpha allele (TNF(z)). Studies of anti-DNA antibodies and lupus nephritis revealed that, compared to (NZB x NZW) F1, the disease of (NZB x NZW.H-2d) F1 was markedly reduced. In (NZB x NZW.PL) F1, the onset of renal disease was significantly delayed, while the extent of proteinuria and renal histopathology in individuals that had developed the disease was comparable to that seen in (NZB x NZW) F1. It seems likely that both class II and TNF-alpha gene polymorphisms are functioning as H-2-linked predisposing genetic elements, and that the TNF-alpha polymorphism acts to modulate an initial process of the renal disease. 相似文献
57.
Lumisight Table: an interactive view-dependent tabletop display 总被引:1,自引:0,他引:1
Kakehi Y. Iida M. Naemura T. Shirai Y. Matsushita M. Ohguro T. 《Computer Graphics and Applications, IEEE》2005,25(1):48-53
A novel tabletop display provides different images to different users surrounding the system. It can also capture users' gestures and physical objects on the tabletop. The Lumisight Table approach is based on the optical design of a special screen system composed of a building material called Lumisty and a Fresnel lens. The system combines these films and a lens with four projectors to display four different images, one for each user's view. In addition, we need appropriate input methods for this display media. In the current state of the project, we can control computers by placing physical objects on the display or placing our hands over the display. This screen system also makes it possible to use a camera to capture the appearance of the tabletop from inside of the system. Our other main idea is to develop attractive and specialized applications on the Lumisight Table, including games and applications for computer-supported cooperative-work (CSCW) environments. The projected images can be completely different from each other, or partially identical and partially different. Users can share the identical parts as public information, because all users can see it. This article is available with a short video documentary on CD-ROM. 相似文献
58.
Shirai M. Arimoto H. Watanabe K. Taike A. Shinoda K. Shimizu J. Sato H. Ido T. Tsuchiya T. Aoki M. Tsuji S. Sasada N. Tada S. Okayasu M. 《Electronics letters》2003,39(9):733-735
A novel travelling-wave electroabsorption optical modulator, electrically matched for 50 /spl Omega/ loads of driving circuit drivers, was developed. The scattering parameter of electric reflection (S/sub 11/) from this modulator is less than -20 dB at 20 GHz. It can thus enable a 40 Gbit/s, 2 km SMF transmission with a 0.3 dB penalty at a 1.3 /spl mu/m wavelength. 相似文献
59.
Experiment and numerical simulation of double-layered RC plates under impact loadings 总被引:1,自引:0,他引:1
Tetsuo Shirai Atsushi Kambayashi Tomonori Ohno Hajime Taniguchi Masatoshi Ueda Nobutaka Ishikawa 《Nuclear Engineering and Design》1997,176(3)
This paper is to investigate and to propose a method to improve the impact resistance of reinforced concrete (RC) plates against projectile impact, and the damage of double-layered RC plates is examined experimentally and simulated analytically. In tests, a projectile launching apparatus, which is a 40 mm smooth-bore airgun, was used. Based on experimental results, numerical simulations with the DYNA-3D code, which takes account of the dynamic constitutive law of concrete, were done to find the applicability of the present computer code to the analysis of double-layered RC plates under high-speed impact loadings. In this study, the impact resistance of concrete plate is defined as the degree of local damage. In both experiments and numerical simulations, the effect of double-layering on the impact resistance is discussed. 相似文献
60.
Takeyuki Suzuki Yoshitaka Dansui Tetsuji Shirai Chikako Tsubaki 《Journal of Materials Science》1985,20(9):3125-3130
The solid solubility limit, grain orientation, defect structure and electrical conductivity of solidified rhombohedral specimens
in the Bi2O3-BaO system are described. The c-axes (in hexagonal notation) of solidified specimens were almost entirely oriented along the platelet/film thickness. Slow-cooling
(∼ 10−2° Csec−1) of the system gave solid solutions with substitutional type of 2BaO → 2BaBi′ + 20+ V
0
..
for 12 to 32 mol % BaO. High-temperature modification of slowly-cooled sample (16 mol % BaO) showed a conductivity of 8.8×10−1 Ω−1 cm −1 at 600° C along the conduction plane (perpendicular to the c-axis). Rapid quenching (∼ 105° C sec−1) produced solid solutions for 8 to 20 mol % BaO introducing interstitial Ba2+ (10–12 mol % BaO) and Schottky type defects such as VBi‴ and V
Bi
‴
and V
0
..
(16 to 20 mol % BaO), however the high-temperature modification of the rhombohedral structure could not be frozen. 相似文献