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101.
Y-K. Sun 《Journal of Applied Electrochemistry》2001,31(10):1149-1153
A new Se-doped spinel material, LiAl0.18Se0.02Mn1.8O4 powder with a phase-pure polycrystalline was synthesized by a sol–gel method. The material in the 3 V region (2.4 3.5 V) and both the 3 and 4 V region (2.4 4.4 V) initially deliver a discharge capacity of 81 and 178 mA h g–1 which increase with cycling to reach 110 and 204 after 50 cycles, respectively. The material shows excellent cycleability in the 4 V region (3.0 4.4 V) with almost no capacity loss. The structural integrity of the Se-doped spinel was characterized by charge–discharge cycling tests and X-;ray diffraction. 相似文献
102.
103.
104.
过氧化物交联聚乙烯的力学性能研究 总被引:6,自引:0,他引:6
采用过氧化物交联方法研究了交联聚乙烯的工艺、配方和性能,探讨了过氧化物用量对材料力学性能及凝胶含量的影响,以及炭黑、氧化锌、抗氧剂对材料性能的影响。结果表明,过氧化物交联聚乙烯的力学性能有一定的提高,随着DCP含量的增加,交联PE的凝胶含量提高,而随着凝胶含量的提高,交联PE的拉伸强度提高,断裂伸长率下降;炭黑对材料有一定的补强作用,氧化锌的加入有助于交联反应和拉伸强度的提高。 相似文献
105.
使用毛细管电泳分离并定量分析了对苯二酚——— 1种黑白显影液中的显影剂和它的衰退反应产物对苯二酚单磺酸盐。优化了的毛细管电泳分离。 相似文献
106.
A series of monomers were prepared by reacting (meth)acryloyl chloride with 2,4‐dihydroxybenzophenone, 2,4‐dihydroxybenzaldehyde, and 2,4‐dihydroxyacetophenone, respectively. The monomers were polymerized in dimethylformamide (DMF) at 70°C using benzoyl peroxide as an initiator. Polymer–metal complexes were obtained from DMF solutions of polymers with an aqueous solution of metal ions. The polymers and polymer–metal complexes were characterized by elemental analysis and spectral studies. The IR spectra of these complexes suggest that the metals are coordinated through the oxygen of the carbonyl group and the oxygen of the phenolic–OH group. The electronic spectra, electron paramagnetic resonance (EPR) spectra, and magnetic moments of polychelates showed an octahedral and square planar structure for Ni(II) and Cu(II) complexes, respectively. X‐ray diffraction studies revealed that polychelates are highly crystalline. The thermal and electrical properties, catalytic activity, and structure–property relationships are discussed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2083–2090, 2003 相似文献
107.
108.
An unequivocal determination of whether pressure independent flux regime is osmotically controlled or gel layer dominated, is still open for discussion in the membrane literature. The present work reports a method that could be used to address this issue. It is shown that analysis of post steady state transient filtration data leads to clear demarcation of osmotically limited and gel layer controlled filtration. The method proposed in this work can also be used to estimate the additional filtration resistance offered by the polarization layer to the permeate flow in macromolecular ultrafiltration and has been verified experimentally. It has also been shown that the polarization layer thickness is not sensitive to the feed pressure but varies as a function of the bulk solute concentration; higher the bulk concentration, thicker is the polarization layer. 相似文献
109.
Preparation and characterization of mesostructured polymer-functionalized sol–gel-derived thin films
B. Smarsly G. Garnweitner R. Assink C. Jeffrey Brinker 《Progress in Organic Coatings》2003,47(3-4):393-400
The present study attempts to incorporate methacrylate-based polymers into ordered lamellar organic/inorganic nanocomposite films composed of alternating SiO2/polymer layers. The films are prepared by dip-coating from a solution containing the monomers and silica precursors, thus leading to composite lamellar mesostructured materials through evaporation-induced self-assembly (EISA). A polymerizable coupling agent is added to covalently link the polymers to the silica matrix. The final polymer/SiO2 hybrid material is obtained by a separate free-radical polymerization step, initiated by UV exposure or thermal treatment. Using trimethoxy(7-octen-1-yl)silane as a coupling agent, a procedure was established that preserved the mesostructure and maintained the swelling properties of the polymers, while acrylate-based coupling agents lead to a significant distortion of the film mesostructure. Structure and composition of the films were studied by X-ray diffraction, NMR and IR. 相似文献
110.
阳离子表面活性剂对HPAM溶液表观粘度的影响 总被引:1,自引:0,他引:1
研究了不同的阳离子表面活性剂对部分水解聚丙烯酰胺(HPAM)溶液中的表观粘度的影响。 相似文献