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粉煤灰制备絮凝剂的研究 总被引:1,自引:0,他引:1
通过高温焙烧、酸浸、碱溶等制备过程,用粉煤灰制取聚硅酸铝铁絮凝剂.用分光光度计法测其浊度去除率,在焙烧温度为800℃时,粉煤灰制取的聚硅酸铝铁絮凝剂的浊度去除率最大,达到了65%左右. 相似文献
995.
Ink‐eliminated sludge flour (IESF), waste residue from the recycling treatments of waste paper, was utilized as a new kind of filler to reinforce polypropylene (PP) in this research work. Different coupling agents, including maleated anhydride grafted PP (MAPP), stearic acid (SA), and titanate (NDZ‐101), were used to increase the compatibility between IESF and PP. By using different measurements, the microstructure, morphology, thermal behaviors, and mechanical properties of the IESF/PP composites were investigated in detail. It was found that IESF, as a nucleation agent, not only induced the crystallization orientation of PP but also accelerate the crystallization rate of PP. Just as indicated in the experiments, the presence of IESF has shown the advantages of increasing the dimensional stability, the hardness and the flexural property, and the presence of coupling agents has a favorable effect on the improvement of dimensional stability. Moreover, the coupling agent has minor influence on the mechanical property, even causes some decrease in the impact strength. Among these three coupling agents, MAPP is found to be the best coupling agent for increasing the interfacial adhesion between IESF and PP, and the MAPP addition makes the PP composite possess the quickest crystallization rate and greatest tensile strength. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 513–520, 2003 相似文献
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Mohammad Reza Aboudzadeh Zhu Jiawen Wu Bin 《Korean Journal of Chemical Engineering》2006,23(1):124-130
The equilibrium and kinetic characteristics of the adsorption of human serum albumin (HSA) and ovalbumin (OVA) to the DEAE
Sepharose FF weak anion exchanger were experimentally determined. The rate for protein adsorption was simulated with two different
models, the first being based on a single lumped kinetic parameter, while the second includes the individual mass transfer
processes occurring prior to the adsorption intervention, i.e., diffusion across the liquid film surrounding individual particles
and diffusion within the ion exchanger particle itself. The actual adsorption of OVA to DEAE Sepharose FF in fully mixed stirred
vessels and in packed bed columns was consistent with both models. In the case of HSA, however, the adsorption profile in
an agitated vessel was consistent only with the pore diffusion model and neither model could correctly predict the latter
part of the breakthrough profile observed in packed bed experiments. 相似文献
999.
聚合型受阻酚抗氧剂的合成及应用 总被引:3,自引:0,他引:3
研究了以对甲酚为主要原料合成聚合型受阻酚抗氧剂的工艺。结果表明,树脂缩合反应条件是对甲酚与双环戊二烯为3:1~1.25,ZnCl2催化剂为对甲酚质量分数的2.0%,反应温度为75~80℃,双环戊二烯滴加时间为2h。烷基化反应温度为70~75℃,H2S04催化剂为缩合树脂质量分数的2.0%。制得的聚合型受阻酚抗氧剂产品对聚氨酯泡沫用聚醚2802具有较好的抗氧化性,起燃温度达224℃。 相似文献
1000.
Analysis of the polyethylene glycol glucosides and FA esters thereof by atmospheric-pressure ionization MS 总被引:1,自引:0,他引:1
Xin?Jin Jinzong?YangEmail author Bingtao?Tang Minggui?Zhu Ning?Yu Yi?Liu 《Journal of the American Oil Chemists' Society》2003,80(6):519-524
Polyethylene glycol (PEG) glucosides (PEGG) and the PEGG esters of lauric acid were analyzed by atmospheric-pressure ionization
MS (API-MS) with electrospray ionization. Straightforward mass characterization of the complex mixtures could be achieved
without prior chromatographic separation. The constituents were identified on the basis of quasi-molecular ions. Individual
components could be observed as protonated molecular ions [M+H]+ and/or as their NH4
+, Na+, or K+ adducts in positive ion mode. The mass spectrometric investigation showed that mixtures of PEGG consisted of monoglucoside,
diglucoside, polyglucoside, and free PEG. The esterification product is a mixture of two types of nonionic surfactants: PEG-laurates
and PEGG-laurates. The reasons for distortion of the quasi-molecular ion intensities and the stabilization of adduct ions
were discussed. The rapid and highly sensitive API-MS analysis technique proposed here is well suited for direct characterization
of complex mixtures and suitable for development as a routine analytical method. 相似文献