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排序方式: 共有582条查询结果,搜索用时 15 毫秒
81.
Akiya Kozawa Hidehiko Oho Mitsuru Sano Dorothy Brodd Ralph Brodd 《Journal of power sources》1999,80(1-2):12-16
Based on the previous success of adding ultra-fine carbon–PVA (polyvinyl alcohol) colloid solution to restore performance of weak batteries, a large scale test programme of practical batteries including those used in forklift, golf cart, taxi cab, truck and bus applications from 150 companies was carried out. More than 95% of the tested batteries exhibited excellent recovery in performance parameters including the specific gravity (S.G.), voltage and operation time (Ah capacity). The work reported here includes basic research studies to understand better the beneficial action of the carbon–PVA colloid additive. 相似文献
82.
Hideki Harano Kenichi Kinoshita Koji Yoshii Toru Ueda Shunsuke Okita Mitsuru Uesaka 《Journal of Nuclear Materials》2000,280(3):255-263
As a promising tool for ultrafast material analyses, we propose to utilize the X-ray pulse which may be generated in a quite simple manner using subpicosecond electron linacs. The properties of the X-ray were numerically studied with the EGS4 code. Verification of the X-ray generation was also conducted at the Nuclear Engineering Research Laboratory (NERL) linac and clear diffraction patterns of characteristic X-ray were obtained for typical single crystals. 相似文献
83.
Mitsuru Kawamoto Kiyotaka Kohno Yujiro Inouye 《Circuits, Systems, and Signal Processing》2007,26(4):473-494
This paper presents eigenvector algorithms (EVAs) for blind deconvolution of multiple-input, multiple-output infinite impulse
response channels (convolutive mixtures). An attractive feature of one of the proposed EVAs is that it is insensitive to Gaussian
noises which are added to the outputs of the channels; hence, the proposed EVA is referred to as a "robust" eigenvector algorithm.
Simulation results show the validity of the proposed EVAs. 相似文献
84.
Tanaka T Takahashi K Sako K Kasegawa R Toishi M Watanabe K Samuels D Takeya M 《Applied optics》2007,46(17):3583-3592
An external-cavity laser with a wavelength of 405 nm and an output of 80 mW has been developed for holographic data storage. The laser has three states: the first is a perfect single mode, whose coherent length is 14 m; the second is a three-mode state with a coherent length of 3 mm; and the third is a six-mode state with a coherent length of 0.3 mm. The first and second states are available for angular-multiplexing recording; all states are available for coaxial multiplexing recording. Due to its short wavelength, the recording density is higher than that of a 532 nm laser. 相似文献
85.
A tunable laser optical source equipped with wavelength and mode-hop monitors was developed to compensate for thermal expansion of the medium in holographic data storage. The laser's tunable range is 402-409 nm, and supplying 90 mA of laser diode current provides an output power greater than 40 mW. The aberration of output light is less than 0.05 lambdarms. The temperature range within which the laser can compensate for thermal expansion of the medium is estimated based on the tunable range, which is +/-13.5 degrees C for glass substrates and +/-17.5 degrees C for amorphous polyolefin substrates. 相似文献
86.
Long-chain polyamines (LCPAs) from marine sponge: possible implication in spicule formation 总被引:1,自引:0,他引:1
Matsunaga S Sakai R Jimbo M Kamiya H 《Chembiochem : a European journal of chemical biology》2007,8(14):1729-1735
Two distinct marine organisms, diatoms and sponges, deposit dissolved silicates to construct highly architectural and species-specific body supports. Several factors such as proteins, long-chain polyamines (LCPAs), or polypeptides modified with LCPAs are known to be involved in this process. The LCPAs contained in the silica walls of diatoms are thought to play pivotal roles in the silica deposition. In sponges, however, a protein called silicatein and several other proteins have been reported to be the factors involved in the silica deposition. However, no other factors involved in this process have been reported. We have identified the LCPAs from the marine sponge Axinyssa aculeata and present here some evidence that sponge-derived LCPAs can deposit silica and that the LCPA derivatives are associated with spicules. The results indicate a common chemistry between sponges and diatoms, the two major players in the biological circulation of silicon in the marine environment. A wide variety of organisms are known to utilize silica in their biological processes. Polyamines or other functional molecules might be involved, in combination with proteins, in their biosilicification process. 相似文献
87.
Naoshi Kozu Toshihiko Kadono ReikoI. Hiyoshi Jun Nakamura Mitsuru Arai Masamitsu Tamura Masatake Yoshida 《Propellants, Explosives, Pyrotechnics》2002,27(6):336-339
A technique for in situ Raman spectroscopy of laser‐shocked nitrobenzene was developed. Raman spectra of shocked nitrobenzene are obtained up to ∼3.5 GPa, and peak shifts at particular frequencies are observed. The shifts are plotted as a function of density and compared with the data under isothermal compression. Both data provide the same results. This indicates that the numbers of peak shifts of nitrobenzene depend solely on material density. 相似文献
88.
Summary 3-(N-Carbazolyl)-1-propyne polymerized with MoCl5- and WCl6-based catalysts to produce a polymer in high yields. The MoCl5 and MoCl5-n-Bu4Sn catalysts were the most effective (the systems solidified immediately after initiation of polymerization with these catalysts). The product polymer was a yellow solid insoluble in any solvent. Copolymerization of the present monomer with tert-butylacetylene by MoCl5-n-Bu4Sn produced a copolymer; it had a high molecular weight (M
w 350,000), completely dissolved in toluene, CHCl3 etc, and formed a free-standing film by solution casting. -N-Carbazolyl-1-hexyne and-1-octyne produced toluene-insoluble polymers with WCl6-Ph4Sn. 相似文献
89.
Masaharu Kamei Sumiko Ohgaki Tamotsu Kanbe Mitsuru Shimizu Shigeru Morita Isao Niiya Isao Matsui-Yuasa Shuzo Otani 《Lipids》1996,31(11):1151-1156
The effects of dietary highly hydrogenated soybean oil (HSO) upon the changes caused by dietary polychlorinated biphenyls
(PCBs) were examined in rats. Six groups of rats were fed the following diets for 30 d: a 20% soybean oil-containing diet
(control diet), a diet in which a half of soybean oil was substituted with HSO (HSO-A diet), a diet in which cellulose powder
was replaced with HSO (HSO-B diet) and these diets supplemented with 100 ppm PCBs (control+PCBs, HSO-A+PCBs and HSO-B+PCBs
diets). Hepatic concentration of PCBs and relative liver weight were markedly decreased in rats fed with the HSO-A+PCBs diet
compared with those fed with the other diets containing PCBs. Liver lipids and liver cholesterol were considerably decreased
with a reciprocal increase in fecal sterol excretion by rats fed the HSO-A+PCBs and the HSO-B+PCBs diets compared with those
fed with the control+PCBs diet. The fatty acid composition in hepatic phospholipids showed an independent increase of the
saturated fatty acid content induced by dietary HSO and PCBs. Dietary PCBs also caused decreases in the amounts of monounsaturated
and n-3 polyunsaturated fatty acids. These results suggest that dietary HSO prevents accumulation of PCBs in the liver and
promotes the excretion of lipids stimulated by PCBs, accompanied by a change in fatty acid metabolism. 相似文献
90.