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61.
Effect of CO2 on layered Li1+zNi1−x−yCoxMyO2 (M = Al,Mn) cathode materials for lithium ion batteries
We investigated the effect of CO2 on layered Li1+zNi1−x−yCoxMyO2 (M = Al, Mn) cathode materials for lithium ion batteries which were prepared by solid-state reactions. Li1+zNi(1−x)/2CoxMn(1−x)/2O2 (Ni/Mn mole ratio = 1) singularly exhibited high storage stability. On the other hand, Li1+zNi0.80Co0.15Al0.05O2 samples were very unstable due to CO2 absorption. XPS and XRD measurements showed the reduction of Ni3+ to Ni2+ and the formation of Li2CO3 for Li1+zNi0.80Co0.15Al0.05O2 samples after CO2 exposure. SEM images also indicated that the surfaces of CO2-treated samples were covered with passivation films, which may contain Li2CO3. The relationship between CO2-exposure time and CO32− content suggests that there are two steps in the carbonation reactions; the first step occurs with the excess Li components, Li2O for example, and the second with LiNi0.80Co0.15Al0.05O2 itself. It is well consistent with the fact that the discharge capacity was not decreased and the capacity retention was improved until the excess lithium is consumed and then fast deterioration occurred. 相似文献
62.
Tetsuro Hori Naoki Fukuoka Tetsuya Masuda Yasuo Miyake Hiroyuki Yoshida Akihiko Fujii Yo Shimizu Masanori Ozaki 《Solar Energy Materials & Solar Cells》2011,95(11):3087-3092
Bulk heterojunction solar cells utilizing soluble phthalocyanine derivative, 1,4,8,11,15,18,22,25-octahexylphthalocyanine (C6PcH2) have been investigated. The active layer was fabricated by spin-coating the mixed solution of C6PcH2 and 1-(3-methoxy-carbonyl)-propyl-1-1-phenyl-(6,6)C61 (PCBM). The photovoltaic properties of the solar cell with bulk heterojunction of C6PcH2 and PCBM demonstrated the strong dependence of active layer thickness, and the optimized active layer thickness was clarified to be 120 nm. By inserting MoO3 hole transport buffer layer between the positive electrode and active layer, the FF and energy conversion efficiency were improved to be 0.50 and 3.2%, respectively. The tandem organic thin-film solar cell has also been studied by utilizing active layer materials of C6PcH2 and poly(3-hexylthiophene) and the interlayer of LiF/Al/MoO3 structure, and a high Voc of 1.27 V has been achieved. 相似文献
63.
Yoshimitsu Uemura Takami Kai Rintarou Natori Takeshige Takahashi Yasuo Hatate Masahiro Yoshida 《Renewable Energy》2004,29(4):581
A study was carried out to see if the potential of renewable energy sources other than hy droelectric power, such as wind, photovoltaic, solar thermal, biomass and waste energy sources, can meet the current energy consumption in Yakushima. The current electricity consumption can be covered by wind and photovoltaic energy sources. The total potential of wind and photovoltaic energy sources is 5.4 times as much as the current electricity consumption. LP gas and kerosene can be replaced by solar thermal and biogas energy. The potential of plant biomass and municipal waste is not sufficient (approximately one third) to cover the rest of the fossil fuels (gasoline, diesel oil and heavy oil). Also, plant biomass and municipal waste must be converted into fluid form. This shortage can be covered by the po tential of wind and photovoltaic energy sources. We also investigated the possibility of tourism expansion using the potential of wind and photovoltaic energy sources. Taking into account three types of capacity (energy, accommodation and transportation), Yakushima can accept approximately four times as many tourists as the current number of tourists. 相似文献
64.
The objective of this study is to experimentally examine the characteristics of transient vortices in the boundary layer on a disk undergoing both rotation and orbital motion. The velocity fluctuations on a rotating, orbiting disk (disk radius equal to orbital radius) are measured by the hot-wire method, and the effects of orbital motion on the transient vortices in the boundary layer are examined. When the ratio of the orbital speed to the speed of rotation is i-0.025, the interval of transient vortices depends on only the orbital radius, regardless of the directions of rota- tion and orbital motion. The rate of low-frequency disturbances increases as the orbital speed increases, and the vortices induced by these low-frequency disturbances travel over the disk and then develop in the region of in- creased velocity. Consequently, no vortices generated on a rotating disk under orbital motion are stationary rela- tive to the disk. 相似文献
65.
Shinji Kubo Masatoshi Futakawa Ikuo Ioka Kaoru Onuki Akihisa Yamaguchi 《International Journal of Hydrogen Energy》2013
Very harsh environments exist in the iodine–sulfur process for hydrogen production. Structural materials for sulfuric acid vaporizers and concentrators are exposed to high-temperature corrosive environments. Immersion tests were carried out to evaluate the corrosion resistance of ceramics and to evaluate corrosion-resistant metals exposed to environments of aqueous sulfuric acids at temperatures of 320, 380, and 460 °C, and pressure of 2 MPa. The aqueous sulfuric acid concentrations for the temperatures were 75, 85, and 95 wt%, respectively. Ceramic specimens of silicon carbides (SiC), silicon-impregnated silicon carbides (Si–SiC), and silicon nitrides (Si3N4) showed excellent corrosion resistance from weight loss measurements after exposure to 75, 85, and 95 wt% sulfuric acid. High-silicon irons with silicon content of 20 wt% showed a fair measure of corrosion resistance. However, evidence of crack formation was detected via microscopy. Silicon enriched steels severely suffered from uniform corrosion with a corrosion rate in 95 wt% sulfuric acid of approximately 1 g m−2 h−1. Among the tested materials, the ceramics SiC, Si–SiC, and Si3N4 were found to be suitable candidates for structural materials in direct contact with the considered environments. 相似文献
66.
Tanaka Y Takahashi K Sasao T Kirigaya T Hosoi S Nagaoka N Kawamura T Nakazawa H 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2003,44(4):181-185
Two peaks, A and B, detected in chromatograms of commercial frozen vegetable extracts during analysis of organophosphorus pesticide residues by GC-FPD, were identified as tris(2,4-ditert-butylphenyl)phosphite (Irgafos 168) and Irgafos 168 oxide, respectively, from their mass spectra. Irgafos 168 is used as an antioxidant in plastics, and there has been no report of its detection in foods. We analyzed Irgafos 168 and its oxide in 38 samples of commercial frozen vegetables, and they were detected from 4 samples (0.02-0.80 microgram/g as total amount of Irgafos 168 and its oxide). 相似文献
67.
Isolation and characterization of predominant microorganisms during decomposition of waste materials in a field-scale composter 总被引:2,自引:0,他引:2
Pedro MS Haruta S Nakamura K Hazaka M Ishii M Igarashi Y 《Journal of Bioscience and Bioengineering》2003,95(4):368-373
A self-heating field-scale composter treating agro-industrial wastes within a period of 30 d was analyzed by denaturing gradient gel electrophoresis (DGGE) (Pedro et al., J. Biosci. Bioeng., 91, 159-165, 2001). Three major bands were derived from Propionibacterium acnes, Methylobacterium mesophilicum or M. radiotolerans, and Bacillus thermocloacae. Strains MSP09A and MSP06G with close affiliation to P. acnes and B. thermocloacae, respectively, were successfully isolated. Based on quantitative-PCR results, the relative population of MSP09A increased towards the end of the composting process (mesophilic stage) while MSP06G seemed to predominate during the middle period (thermophilic stage). These results correlated highly with their growth temperatures. MSP09A and MSP06G had different metabolic profiles which were largely affected by culture conditions. MSP09A was able to utilize large complex molecules of lipids and proteins. An interspecies relationship in terms of metabolites such as propionic acid was expected between the two microorganisms. 相似文献
68.
Yasuo Ueno Daniel E. Rosner Rosa G. dePena Julian P. Heicklen 《The Science of the total environment》1982
Lead aerosols were generated to investigate the conditions for the formation of monodisperse aerosols in nitrogen stream. Aerosols of high monodispersity could be obtained by vaporizing lead at a temperature in the range of 1000° to 1150°C and by flowing nitrogen at a rte of 1.5 l/min.In order to produce “lead iodide aerosols” portions of the lead aerosols were conducted into a test chamber in which the atmosphere of iodine vapor had previously been prepared. This mixture containing the aerosols with low concentration was moderately stirred under different temperatures.“The lead iodide aerosols” were sampled with a syringe to be injected into a modified Bigg's test device for ice nucleation. The aerosols injected rapidly changed into ice crystals, which could grow in size. As the number of ice crystals could give that of lead iodide aerosols, the reactivity of lead aerosols with iodine vapor was investigated under various temperatures. An increase in temperature during the ageing of lead aerosols with iodine vapor promoted their reactivity. 相似文献
69.
Succinate dehydrogenase (SDH) of Saccharomyces cerevisiae consists of four subunits encoded by the SDH1, SDH2, SDH3, and SDH4 genes. We determined the effect of SDH deficiency on the productivity of organic acids in a sake yeast strain Kyokai no. 9. The SDH activity of single disruptants was retained at 30-90% of that of the wild-type strain, but the activity disappeared in double disruptants of the SDH1 and SDH2 or SDH1b (the SDH1 homologue) genes. Two double disruptants showed no growth on a medium containing glycerol as the sole carbon source, while the single disruptants could utilize glycerol. These results indicate that double disruption of the SDH1 and SDH2 or SDH1b genes is required for complete loss of SDH activity and that the SDH1b gene compensates for the function of the SDH1 gene. The sdh1 sdh1b disruptant showed a marked increase in succinate productivity of up to 1.9-fold along with a decrease in malate productivity relative to the wild-type strains under shaking conditions. Under both static and sake brewing conditions, the productivity of these organic acids in the disruptants was virtually unchanged from that in the wild-type strain. Furthermore, SDH activity was undetectable in the wild-type and the disrupted strains under static conditions. These results suggest that SDH activity contributes to succinate production under shaking conditions, but not under static and sake brewing conditions. 相似文献
70.
Enhancing heat transfer ability of drag reducing surfactant solutions with static mixers and honeycombs 总被引:4,自引:0,他引:4
Yunying Qi Yasuo Kawaguchi Richard N. Christensen Jacques L. Zakin 《International Journal of Heat and Mass Transfer》2003,46(26):5161-5173
Solutions containing drag reducing additives also show reduced heat transfer which limits their use in district heating and cooling recirculation systems where heat exchange is critical. In this study, static mixers A and B and honeycombs were installed at the entrance to a heat exchanger to break the solution microstructure temporarily and thereby enhancing their heat transfer ability when passing through the heat exchanger. The effectiveness of the destructive devices in enhancing the heat transfer ability of drag reducing cationic and mixed zwitterionic/anionic surfactant solutions was investigated together with the microstructure recovery time and pressure drop penalty paid for the heat transfer enhancement. 相似文献