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排序方式: 共有1327条查询结果,搜索用时 15 毫秒
101.
Atsushi Sano Masato Kurihara Kazuya Ogawa Tsuyoshi Iijima Satoshi Maruyama 《Journal of power sources》2009,192(2):703-707
The effect of alkali function group contained in electrode binder was investigated. Carboxy methyl cellulose (CMC) improved the initial irreversible capacity loss in graphite negative electrode. Lithium acetate also improved the initial cycle efficiency. On the other hand, ethyl cellulose (EC) and hydroxyl propyl methyl cellulose (HPMC), which do not have a carboxylic group, did not decrease the reductive electrolyte decomposition. After charge and discharge cycle, the surface film composition on the electrode with CMC was less than on the electrode without CMC. This suggests that a carboxylic group in the binder acted as a catalyst and promoted the solid electrolyte interphase (SEI) formation which prevents the excess electrolyte decomposition on the graphite electrode. 相似文献
102.
Ahmed J. Samed Takayuki Tanaka Keita Ikeue Masato Machida 《Topics in Catalysis》2010,53(7-10):591-596
Catalytic NO–H2–CO–O2 reaction was studied over Pt-supported Ln-incorporated FSM-16 (Ln = La, Ce and Pr). Pr-FSM-16 exhibited the highest activity for NO x reduction at ≤200 °C. Pr has an effect of increasing the basicity to promote the oxidative adsorption of NO, which is a key for efficient de-NO x . 相似文献
103.
Oxygen potentials of oxide nuclear fuels are important thermodynamic data in development of nuclear fuel technologies. Minor actinide bearing MOX (mixed oxide) fuels have been developed as sodium cooled fast reactor fuels. Content of Am which is one of the minor actinide elements causes oxygen potentialto increase. The effects of the oxygen potential increase on the irradiation behavior were evaluated. Profiles of temperature and O/M (oxygen-to-metal) ratio in the pellets were evaluated to better understand the irradiation behavior. From these data, local oxygen potential in the radial direction of the pellets was calculated, and was compared with free energy of compounds composed of fission products. Based on this comparison, it was concluded that Cs2MoO4 was likely formed at pellet periphery of (U07Pu03)O1.98 and (U0.66Pu03Amoo16Npo.016)Ol.976 The extent of cladding tube inner surface oxidation was predicted by using the calculated oxygen potential. No significant difference between irradiation behaviors of (Uo.7Puo3)O2_x and (U0.66PUo 3Amo.016Npo.016)O2.x pellets was confirmed. 相似文献
104.
Eu-activated BaAl2 S4 (BaAl2 S4 :Eu) blue light emission phosphor has attracted considerable attention recently as a prospective material for full color electroluminescent display applications. Although BaAl2 S4 :Eu was discovered over 30 years ago, the solid-state reaction between metal sulfides in sealed quartz ampoules remains the main method for the synthesis of this material. In this work, a homogeneous single-phase Ba0.95 Eu0.05 Al2 S4 (BaAl2 S4 :Eu) phosphor was obtained by the sulfurization–reduction of the multicomponent oxide precursor in a CS2 atmosphere at 1050°C. The oxide precursor containing barium, aluminum, and europium for this process was prepared by the polymerizable complex method, which ensures a high degree of homogeneity in the final product. The BaAl2 S4 :Eu material thus obtained exhibited a single emission line at 475 nm and a fluorescence intensity of 35% compared with one of the best commercially available (Ba,Eu)MgAl10 O17 phosphors. 相似文献
105.
This study experimentally investigated the possibility of stable burning conditions of liquid fuel inside a narrow tube using an electrospray technique without external heating or a catalyst. The mixture of 30% volume ethanol and 70% volume n-heptane was used as a liquid fuel atomized by the electrospray method with single capillary-ring extractor-mesh collector electrode configuration placed inside a quartz glass tube with an inner diameter of 3.5 mm. A stable flame was established inside the narrow tube without wall wetting within a certain range of equivalence ratio for a fuel flow rate of 1 mL/h. This study confirmed that the role of the mesh as the collector was very important in establishing a stable flame inside the narrow tube. If the fuel flow rate was sufficiently large, wall wetting occurred and eventually stable burning stopped. 相似文献
106.
107.
H Ohtsuka T Higuchi H Matsuzawa H Sato K Takahashi J Takahashi TO Yoshino 《Canadian Metallurgical Quarterly》1997,59(11):1075-1077
The inhibitory effect of chlorpromazine (CPZ), pentoxifylline (PTX) and dexamethasone (DEX) was investigated in a model of endotoxin shock in Holstein calves following an intravenous administration of Esherichia coli endotoxin (LPS). Initial correlations with its effects on the levels of tumor necrosis factor (TNF), a pivotal mediator of endotoxin shock, and clinical signs were obtained. The pretreatment of CPZ or DEX significantly decreased the serum levels of TNF, and reduced endotoxic shock. But the pretreatment of PTX hardly reduced the increase of serum TNF levels and endotoxin shock. The levels of serum endotoxin were not significantly different a minute of postinjection of LPS in calves. The results of this study indicate that pretreatment of CPZ or DEX inhibit various biological effects on endotoxin in calves. 相似文献
108.
Structural Changes of Scandia-Doped Zirconia Solid Solutions: Rietveld Analysis and Raman Scattering 总被引:1,自引:0,他引:1
Hirotaka Fujimori Masatomo Yashima Masato Kakihana Masahiro Yoshimura 《Journal of the American Ceramic Society》1998,81(11):2885-2893
Powder X-ray diffractometry (XRD) and Raman scattering measurements were used to study the structural changes of compositionally homogeneous metastable ZrO2 solid solutions induced by ScO1.5 doping. The crystal structures of monoclinic, tetragonal, cubic, and rhombohedral (Sc2 Zr7 O17 , ß-phase) solid-solution phases have been refined by using the Rietveld analysis of the XRD data at room temperature of arc-melted ZrO2 - X ScO1.5 ( X = 0, 2, …, 20, and 22 mol%) samples. The results can be interpreted as indicating that the structures of the monoclinic and tetragonal phases approach those of the tetragonal and cubic phases, respectively, by ScO1.5 doping. Raman scattering, as well as XRD, was useful to investigate the phase assemblage. Moreover, we could obtain Raman spectra of the ß-phase probably for the first time. 相似文献
109.
Y Ohtsuka K Udaka Y Yamashiro H Yagita K Okumura 《Canadian Metallurgical Quarterly》1998,160(9):4635-4640
Duchenne muscular dystrophy is a lethal and common X-linked recessive disease caused by a defect in dystrophin. Normal myoblast transplantation and dystrophin gene transfer have been expected to correct the deficiency in the muscles, but their clinical application has been hampered by the limited preservation of dystrophin-positive myofibers. In this study we investigated the mechanism for immunologic rejection of normal C57BL/10 (B10) myoblasts transplanted into dystrophin-deficient mdx mice, an animal model of Duchenne muscular dystrophy. We found that mdx mice develop CTL specific for dystrophin itself, which were CD8 dominant and restricted by H-2Kb. We identified several antigenic peptides derived from dystrophin that bind to H-2Kb and are recognized by the mdx anti-B10 CTL. Immunologic tolerance against dystrophin was successfully induced by i.v. injection of these peptides before B10 myoblast transplantation, which resulted in sustained preservation of dystrophin-expressing myofibers in mdx mice. These results demonstrate that dystrophin is antigenic in dystrophin-deficient mice and that immunologic regimen would be necessary to achieve the persistent expression of introduced dystrophin in the muscles of dystrophin-deficient individuals. 相似文献
110.