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931.
最小自由能法求解GAP在等压绝热条件下的燃烧产物 总被引:6,自引:1,他引:6
采用最小自由能法计算了GAP在等压绝热条件下的燃烧温度以及产物的比例,从理论上说明了GAP的燃烧特点。计算结果显示,GAP燃烧产物中有较多的固态C、气态H2、CO等可以再燃烧的物质存在。 相似文献
932.
933.
煤基高分子复合材料研究现状及发展趋势 总被引:3,自引:0,他引:3
介绍了煤基高分子复合材料研究现状,包括煤粉填料、神府煤/高密度聚乙烯共混体系、特种无烟煤粉共混塑料、煤/聚己内酰胺复合材料、风化煤腐殖酸/聚己内酰胺复合材料和傅一克烷基化改性煤/聚丙烯复合材料,以及煤基高分子复合材料的应用,并分析了煤基高分子复合材料的发展趋势。 相似文献
934.
935.
耐盐性高吸水树脂的研究进展 总被引:5,自引:0,他引:5
综述了近年来国内外提高吸水树脂耐盐性的研究进展,概述了高吸水树脂的结构和吸水机理,归纳了引入亲水单体、降低树脂颗粒微环境的盐浓度等提高吸水树脂耐盐性的方法。 相似文献
936.
937.
Electro-organic synthesis without supporting electrolyte: Possibilities of solid polymer electrolyte technology 总被引:1,自引:0,他引:1
J. Jörissen 《Journal of Applied Electrochemistry》2003,33(10):969-977
The application of ion exchange membranes as solid polymer electrolytes (SPE) in fuel cells is state-of-the-art. This technology needs no supporting electrolyte; consequently it can be applied for electro-organic syntheses in order to save process steps. In this case the process is not predetermined to a maximized energy efficiency so that the selection of the cell design, of the electrode materials and of the operating conditions can be focused on a high selectivity of the electrode reactions. The electro-osmotic stream, which is caused by the solvation shells of the ions during their migration through the membrane, and hence is a typical property of SPE technology, has a significant effect on the electrode reactions. It generates enhanced mass transfer at the electrodes, which is beneficial for reaction selectivity. It can be influenced by the choice of, and possibly by the preparation of, the membrane. An additional remarkable advantage of SPE technology is the exceptional long durability of oxide coated electrodes. By combination of several process engineering methods stable operation of SPE cells has been realized, even for examples of non-aqueous reaction systems. Experiments up to 6000 h duration and in cells of up to 250 cm2 membrane area show the potential for industrial application. 相似文献
938.
Compatibility of acidic (H), Na, and Zn neutralized sulfonated polystyrene ionomer blends with Poly(2,6-dimethyl- 1,4-phenylene
oxide) (PPO) and Poly(2,6-dichloro- 1,4-phenylene oxide) (PDCIPO) was investigated by Dilute Solution Viscometry (DSV) and
Differential Scanning Calorimetry (DSC). The intrinsic viscosities of the blends, are measured in suitable solvents. The degree
of compatibility of the blends is characterized by Δb parameter. According to the results, PPO is completely miscible, except
for Na-neutralized 1.7 mol% sulfonated polystyrene (Na1.7SPS) which is completely immiscible with PPO and PDClPO. PDClPO is
completely miscible with Zn-neutralized sulfonated polystyrene (Zn4.8SPS) and partially miscible with acid sulfonated polystyrene
(4.8SPS).
Received: 12 August 2001/Revised version: 21 January 2002/Accepted: 11 March 2003
Correspondence to Leyla Aras 相似文献
939.
A. Z. El-Sonbati A. S. Al-Shihri A. A. El-Bindary 《Journal of Inorganic and Organometallic Polymers》2003,13(2):99-108
Copper(II) polymer complexes of empirical formula [Cu(ligand)2X2] (where X = Cl, Br, I, NO3, and
SO4) and [Cu(ligand)(CH3COO)2] have been prepared with poly(3-phenylacrylidine semicarbazone). All the polymer complexes prepared have been characterized by elemental analysis, magnetic moment, conductance, IR, electronic, 1H-NMR, and electronic paramagnetic resonance spectral studies. The polymer complexes [Cu(ligand)2X2] and [Cu(ligand) (CH3COO)2] may have tetragonal symmetry while the [Cu(ligand)2(
SO4)2] may be five-coordinate trigonal bipyramidal in structure. All complexes exhibit normal magnetic moments corresponding to one unpaired electron except [Cu(ligand)(CH3COO)2] which shows a subnormal magnetic moment. EPR spectra of the polymer complexes have been studied with a view to assigning their stereochemistries. Various EPR parameters have been calculated. The g, A, G values for all the polymer complexes are consistent with a tetragonal 1–5 and trigonal bipyramidal 6 stereochemistry in the Cu(II) polymer complexes of homopolymer. 相似文献
940.
G. Ya. Mamontov 《Combustion, Explosion, and Shock Waves》2003,39(6):670-676
The temperature fields in coked layers of polymer composite materials (fiberglass plastics) under hightemperature heating and subsequent cooling in a cold oxidizer flow are experimentally studied. Based on the analysis of experimental data and numerical research, it is shown that exothermal chemical reactions can proceed in the coked layer of fiberglass plastics, which creates conditions for maintaining high temperatures in the compositecoke layer during a rather long time. 相似文献