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101.
Low crosslinked copolymer of linear and hyperbranched polyurethane (CHPU) was prepared, and the ionic conductivities and thermal properties of the composite polymer electrolytes composed of CHPU and LiClO4 were investigated. The FTIR and Raman spectra analysis indicated that the polyurethane copolymer could dissolve more lithium salt than the corresponding polymer electrolytes of the non crosslinked hyperbranched polyurethane, and showed higher conductivities. At salt concentration EO/Li = 4, the electrolyte CHPU30‐LiClO4 reached its maximum conductivity, 1.51 × 10?5 S cm?1 at 25°C. DSC measurement was also used for the analysis of the thermal properties of polymer electrolytes. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 3607–3613, 2007 相似文献
102.
103.
采用电导法研究了水溶液中盐的浓度与其电导率的关系,根据模拟水样和实际水样在电导率与全盐量的关系上有较好的吻合性,介绍了电导法测定水中全盐量的方法,结果表明在低浓度范围内电导率与盐浓度成线性关系,与传统的重量法相比,具有快速、简便、准确度高的特点。 相似文献
104.
Tsutomu Osawa Masashi Ando Saori Sakai Tadao Harada Osamu Takayasu 《Catalysis Letters》2005,105(1-2):41-45
The role of acetic acid added to the reaction media for the enantio-differentiating hydrogenation of methyl acetoacetate over
a (R,R)-tartaric acid-in-situ-modified nickel catalyst was studied from the viewpoint of the hydrogenation rate during repeated
runs. The hydrogenation of methyl acetoacetate on the “enantio-differentiating sites” of a tartaric acid-modified nickel catalyst
was specifically accelerated by the acetic acid added to the reaction media to increase the enantio-differentiating ability
of the catalyst. In order to increase the enantio-differentiating ability, the addition of acetic acid to the reaction media
was required in each run during the repeated use of the catalyst. 相似文献
105.
106.
化工生产过程控制中气动薄膜调节阀的选择 总被引:2,自引:0,他引:2
本文就气动薄膜调节阀类型、作用方式、流量特性和口径大小的选择,结合化工生产的特点作了较详细地阐述。 相似文献
107.
Several onium cations having vinyl group formed ionic liquids after coupling with bis(trifluoromethanesulfonyl)imide. These monomers were polymerized, and the relation between onium cation structure and properties of thus polymerized ionic liquids was investigated. The polymerized ionic liquid having ethylimiadzolium cation unit showed the highest ionic conductivity of around 10−4 S cm−1 at 30 °C among the obtained polymers reflecting the lowest glass transition temperature of −59 °C. These polymers were thermally stable and their decomposition temperatures were about 350 °C. The ionic conductivity of the polymerized ionic liquids decreased by both the addition of lithium bis(trifluoromethanesulfonyl)imide and the polymerization in the presence of cross-linker. However, the polymerized ionic liquid having 1-methylpiperidinium cation structure showed good lithium ion transference number of 0.43 at room temperature. 相似文献
108.
Utilizing the solvothermal synthesis technique, lithium intercalated tungsten disulfide LixWS2 with x > 1 was obtained, which was allowed to react with water to the formation of single-molecule-layer suspension of tungsten disulfide. The layered nanocomposites PEG, PEO/WS2, intercalating poly(ethylene glycol) (PEG, MW ≈ 1 × 103, 6 × 103, 1 × 104) and poly(ethylene oxide) (PEO, MW ≈ 3 × 105) into the tungsten disulfide host galleries, were prepared using the improved exfoliation-adsorption technique. It was revealed that the intercalated polymers within the host galleries are in a double-layer arrangement with an interlayer expansion of about 9 Å. Despite high conductivity of the host material, those of the PEG, PEO/WS2 nanocomposites were found to be high in the order of 1 × 10−2 to 10−3 S cm−1 at ambient temperature, resulted from the guest-host charge transfers. 相似文献
109.
炭黑对轮胎胎面胶热物性的影响 总被引:1,自引:0,他引:1
研究了炭黑品种和用量对轮胎胎面胶热扩散系数(α)、导热系数(λ)及比热容(C)3种热物性参数的影响规律。结果表明,随着炭黑填充量的增加,胎面胶的α及λ均逐渐增大,C逐渐减小。炭黑的结构性对胎面胶α的影响程度大于炭黑的粒径;温度相同时,炭黑的结构性越高,其填充胎面胶的α越大;随着炭黑填充量的增加,3种炭黑填充胎面胶α之间的差距呈现先增大后减小的变化趋势。炭黑的结构性及粒径对胎面胶C的影响没有固定的规律,但在低温区,炭黑的粒径越大,其填充胎面胶的C越大,且炭黑填充量对此差距无影响。炭黑的结构性对胎面胶λ的影响程度大于炭黑的粒径;温度相同时,炭黑的结构性越高,其填充胎面胶的λ越大;当炭黑用量较低时,其对胎面胶λ的影响程度相对较小,随着炭黑填充量的增加,3种炭黑填充胎面胶λ之间的差距呈现先增大后减小的变化趋势。 相似文献
110.
Koji Watari Hiromi Nakano Kimiyasu Sato Kazuyoshi Urabe Kozo Ishizaki Shixun Cao Katsunori Mori 《Journal of the American Ceramic Society》2003,86(10):1812-1814
The thermal conductivity of a SiC ceramic was measured as 270 W·m−1 ·K−1 at room temperature. At low temperatures ( T < 25 K), the decrease in the conductivity was proportional to T 3 on a logarithmic scale, which indicated that the conductivity was controlled by boundaries. The calculated phonon mean free path in the ceramic increased with decreased temperature, but was limited to ∼4 μm, a length almost equal to the grain size, at temperatures below 30 K. We concluded that the thermal conductivity of the ceramic below 30 K was influenced significantly by grain boundaries and grain junctions. 相似文献