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设计了一种基于多功能热管的高效吸附式制冰机组,采用氯化钙/活性炭复合吸附剂和氨作为吸附工质对。吸附床的加热解吸、冷却吸附及回热过程均由热管工作完成,对该新型吸附制冰机组进行了回质回热研究,结果表明,回质回热型循环可使机组的制冷性能系数COP提高25.5 %,加热量减小约13 %,同时冷却器负荷降低约21 %;采用先回质后回热方式,在回质过程中继续加热解吸床可进一步增加机组制冰量。与传统回质相比,系统COP和单位质量吸附剂制冷功率SCP提高幅度均在15 %以上,且机组SCP的提高幅度高于COP的幅度;吸附制冰机组性能随冷却水温度的升高而下降,但系统的SCP始终维持在较高的水平。当冷却水温度为27℃、蒸发温度为-18.9℃时,系统的SCP仍然高达356.5 W·kg-1。 相似文献
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Two kinds of novel chelating adsorbents have been synthesized to separate boron from aqueous solutions. One is the boron-specific chelating resin, synthesized by the functionalization of macroporous poly (glycidyl methacrylate-co- trimethylolpropane trimethacrylate), with N-methylglucamine. The other is the organic-inorganic hybrid mesoporous SBA-15 with polyol functional groups, prepared by a two-step post-grafting method. The resin can adsorb boron in almost all pH range, and its maximum uptake capacity reaches 1.15 mmol/g. The present study of the polyol-functionalized SBA-15 shows that the post-grafting is successful and the resulting adsorbent has the uptake capacity of 0.63 mmol/g. 相似文献
44.
苯乙烯系阻燃塑料合金的研究进展 总被引:4,自引:0,他引:4
综述了国内外近年来在苯乙烯系阻燃塑料合金方面的研究进展。主要介绍了高聚物型卤系阻燃剂、磷系阻燃剂、有机硅系阻燃剂等阻燃剂的特性及其在提高苯乙烯系塑料合金阻燃性能方面的应用,这些阻燃剂对环境友好,不仅能显著提高塑料基材的阻燃性能,而且力学性能和加工性能也得到改善。此外,还简要介绍了纳米复合技术在提高苯乙烯系塑料阻燃性能中的应用。 相似文献
45.
Intercalated nanocomposites with poly(butylene terephthalate) (PBT) incorporated between the montmorillonite layers were synthesized from dimethyl terephthalate and 1,4-butane diol by using an in situ interlayer polymerization. The PBT nanocomposites were melt-spun at different organoclay contents to produce monofilaments. The samples were characterized by using wide angle X-ray diffraction, electron microscopy, thermal analysis, and tensile testing. The extent of the clay layer in the PBT was confirmed by using X-ray diffraction and electron microscopy, and the clay layer was found to be highly dispersed on a nanometer scale. The addition of only a small amount of organoclay was enough to improve the thermo-mechanical properties of the PBT hybrid fibers. The hybrids were extruded with various draw ratios (DRs) to examine the tensile mechanical property of the fibers. At DR=1, the ultimate tensile strength of the hybrid fibers increased with the addition of clay up to a critical content and then decreased. However, the initial modulus monotonically increased with increasing amount of organoclay in the PBT matrix. When the DR was increased from 1 to 6, for example, the strength and the initial modulus values of the hybrids containing 3 wt% organoclay decreased linearly. 相似文献
46.
变压吸附在气体分离单元的应用 总被引:5,自引:0,他引:5
简述了变压吸附在气体分离单元操作的原理,并介绍了变压吸附装置的分类情况,指出变压吸附技术的发展趋势:研发新型吸附剂和工艺流程;加强硬件整改,如采用多塔流程及密相装填技术、研制高密封的程控阀门。 相似文献
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橡胶/蒙脱土纳米复合材料的优异性能使其成为橡胶工业中富有潜力的一类新型材料。笔者综述了三元乙丙橡胶(EPDM)/蒙脱土纳米复合材料的制备方法、性能和工业应用领域等,讨论了蒙脱土片层的表面修饰、插层剂的选择以及复合材料的制备方法对材料性能的影响,并提出了三元乙丙橡胶/蒙脱土纳米复合材料这一新型橡胶材料在轮胎工业上的应用前景。 相似文献
50.
In this study, poly(ethylene terephthalate) (PET)/SiO2 nanocomposites were synthesized by in situ polymerization and melt‐spun to fibers. The superfine structure, physical properties, and dyeability of alkaline hydrolyzed PET/SiO2 nanocomposite fibers were studied. According to the TEM, SiO2 nanoparticles were well dispersed in the PET matrix at a size level of 10–20 nm. PET/SiO2 nanocomposite fibers were treated with aqueous solution of sodium hydroxide and cetyltrimethyl ammonium bromide at 100°C for different time. The differences in the alkaline hydrolysis mechanism between pure PET and PET/SiO2 nanocomposite fibers were preliminarily investigated, which were evaluated in terms of the weight loss, tensile strength, specific surface area, as well as disperse dye uptake. PET/SiO2 nanocomposite fibers showed a greater degree of weight loss as compared with that of pure PET fibers. More and tougher superfine structures, such as cracks, craters, and cavities, were introduced, which would facilitate the certain application like deep dyeing. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3691–3697, 2006 相似文献