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31.
本文分别研究了ZrO2(MgO)固体电解质管头壁厚,参比电极量对定氧测头响应时间的影响,得出了以ZrO2管头壁厚为0.60-0.80mm,Cr/Cr2O3参比电极加入量为40-60mg所组成的定氧测头响应速度最快,同时采用了“双偶法”对定氧测头在工作过程中的热平衡态进行了研究。结果表明:氧浓差电池中的传热是响应过程的控速步骤,氧电势曲线上峰值的产生是起源于电池中的热平衡态。 相似文献
32.
研究了纳米SiO2添加到铅酸蓄电池的极板和电解液中,对电池的起动性能和循环性能的影响。 相似文献
33.
Makoto Ue 《复旦学报(自然科学版)》2007,(5)
1 Results Electrochemical energy storage devices such as lithium-ion batteries[1-2] and double-layer capacitors[3-4] have attracted a great deal of attention because of their potential application to electric hybrid vehicles. They utilize nonaqueous electrolyte solutions comprising from organic solvents and lithium or quaternary ammonium salts with fluorine-containing anions. This is because the relatively large anions with electron-withdrawing atoms enable ionic dissociation in dipolar aprotic solvents... 相似文献
34.
Synthesis of Bioactive and Porous Organic-Inorganic Hybrids for Biomedical Applications 总被引:2,自引:0,他引:2
Kanji Tsuru Satoshi Hayakawa Akiyoshi Osaka 《Journal of Sol-Gel Science and Technology》2004,32(1-3):201-205
Bioactivity has been exhibited by a limited range of ceramics since the invention of Bioglass®. Recently, some bioactive polymeric organic-inorganic hybrids were introduced, including not only organically modified silicates (Ormosils) synthesized from polydimethylsiloxane (PDMS) and tetraethoxysilane but also those with gelatin and 3-glycidoxypropyl-tremethoxysilane. Preparation of the bulk and porous hybrids and their polymeric structures analyzed by Si NMR spectroscopy were presented. In vitro bioactivity or apatite deposition in a simulated body fluid of the Kokubo recipe were also described for those hybrids. Freeze-drying techniques introduced porosity (up to 90%) and pores extending in a preferred direction. 相似文献
35.
A novel and cost-effective sol-gel process for preparation of MgAl2O4 spinel nanometer powders has been developed in this study. A solution of magnesium and aluminum nitrates in stoichiometric proportion was successfully embraced in the biology polysaccharide gel network, formed by the synergistic interaction between xanthan gum (XG) and locust bean gum (LBG) utilizing their broad-spectrum stability of salt tolerance and character of transformation from sol to gel on the condition of proper temperature and relative proportion of polymeric components. Dry gel could be obtained by vacuum dehydration of aqueous gel at low temperatures. Monolithic MgAl2O4 spinel nanometer powders were produced by calcining the dry gel above 800°C, with average crystallite size of 20 nanometers. 相似文献
36.
D. Kaneko T. Narita J. P. Gong Y. Osada J. Ando K. Yamamoto S. Ohnishi V. V. Yaminsky 《Journal of Polymer Science.Polymer Physics》2003,41(22):2808-2815
The effect of the shear flow on the thickness change of a polyelectrolyte membrane grafted onto a glass substrate was directly investigated with a flow cell combined with a confocal laser scanning microscope. The membrane thickness decreased proportionally to an increase in the shear stress of the flow when the shear rate exceeded a critical value of 1 s?1. The higher the ionic strength was of the fluid, the greater the thinning effect was. The correlation between the critical shear rate and the relaxation of the polymer in the gel membrane was examined. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2808–2815, 2003 相似文献
37.
Precipitate-forming chemical reactions have been studied in chemically cross-linked poly(vinyl alcohol) gel medium. One of the reactive components was incorporated into the gel, the other was allowed to diffuse into it. Depending on the experimental conditions the reaction-diffusion process often results in patterns of different type. Experiments performed in tubes and in thin layers were carried out in order to investigate the effects of various factors (cross-linking density, swelling degree as well as the concentrations of the outer and inner electrolytes) on the morphologies of the precipitate patterns. It was found that precipitation occurs not only in the Liesegang bands, but also between bands. Beside Liesegang-type structures, tree-like patterns have been observed, showing a characteristic periodicity in the density profile obtained by digitalized image analyses. 相似文献
38.
Thierry Woignier G. Pochet H. Doumenc P. Dieudonné L. Duffours 《Journal of Sol-Gel Science and Technology》2007,41(1):25-30
Volcanic (allophanic) soils are interesting in terms of the control of the greenhouse effect and the knowledge of the porous
features is of importance to understand the mechanism of C and N sequestration. These soils contain a peculiar clay: allophane
aggregates quite close to the synthetic mineral gels aggregates. These volcanic materials behave as gels during drying with
a large irreversible shrinkage that can modify the soil physical properties. Consequently, as for silica gels, we use the
CO2 supercritical drying procedure (SD) to control the drying step and to preserve the structural and textural properties of
the soils. The experimental results show that the N and C content in the soils is clearly dependent on the allophane content.
We also show that the textural properties, such as specific surface area, are higher for the supercritically dried samples,
compared to the classically dried samples, and SAXS results confirm the preserving effect of the SD. With these data, we propose
possible effects of the specific surface area on the C and N content of the allophanic soils. 相似文献
39.
采用循环伏安法,对SPEPt电极以及SPEAu-Pt电极上还原态CO2的电化学氧化行为研究表明,此类电极的电化学特性与光滑Pt电极一致:CO2在氢原子吸附电位区0~250mV(vs.RHE)处,可与电极上化学吸附的氢反应,生成还原态的CO2,通过线性扫描,还原态CO2即发生一不可逆电化学氧化过程(阳极剥离).在SPEPt系列及SPEAu-Pt系列上CO2的电化学行为表明,当SPEPt系列上Pt的载量为2.5mL的0.01mol·L-1H2PtCl6的Pt时,对还原态CO2的电催化活性最好,当Pt的载量相同时,在SPEAu-Pt上,催化剂对还原态CO2的电化学氧化行为比SPEPt电极更强,这是由于预先沉积的Au对后沉积的Pt有调制作用. 相似文献
40.