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991.
马来酸酐在炭黑表面接枝聚合的研究 总被引:5,自引:0,他引:5
研究了过氧化苯甲酰引发马来酸酐在炭黑表面的接枝聚合反应,探讨了反应时间、引发剂用量、接枝单体用量对接枝率的影响。结果表明,接枝率随反应时间的延长而增加,但2h后,接枝率增加不多;随引发剂用量的增加,接枝率呈上升趋势,但用量在15mg以后,接枝率趋于定值;随接枝单体用量的增加,接枝率直线上升。在本实验条件下,接枝率达到9%。通过接枝产物的X射线光电子能谱及红外分析可以证实,马来酸酐已接枝到炭黑表面。从光学显微图像分析结果可知,马来酸酐接枝改性对炭黑在聚合物基体中的分布和分散性能起到良好的改善作用。 相似文献
992.
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996.
生物膜载体吸附剂对Zn2+的吸附 总被引:1,自引:0,他引:1
本文对生物膜吸附Zn^2+的行为进行了准一级动力学方程和Elovich模型方程的拟合,对实验测定的吸附等温线用Langmuir与Freundlich吸附模型进行拟合;考察了pH值及温度对生物膜吸附Zn^2+的影响。结果表明,Zn^2+在生物膜载体吸附剂上的吸附动力学过程与Elovich方程有较好的拟合度,R^2=0.99994。单一等温吸附过程与Langmuir方程具有较好的拟合度,R^2=0.99785;pH=6~8,室温25℃对Zn^2+分有较高的去除率。 相似文献
997.
Three series of polyurethane adhesives—polyethyleneadipateurethane (PEAU), polybuthyleneadipateurethane (PBAU), and polyhexyleneadipateurethane (PHAU)—with the same MW and hard/soft segment ratio, based on the three polyesters polyethyleneadipate (PEA), polybuthyleneadipate (PBA), polyhexyleneadipate (PHA), with 4,4′-diphnylmethane diisocyanate (MDI), and butendiol were synthesized by solution polymerization. The crystallinity of these polyesters and polyurethanes (PUs) and the compatibility of blends of PUs with PVC were studied by means of wide-angle x-ray diffraction (WAXD), differential scanning calorimetry (DSC), dynamic thermomechanical analysis (DMA), testing of solubility, and phase contrast microscopy. The results indicated that PBAU/PVC and PHAU/PVC were compatible systems, but PEAU/PVC was incompatible. The adhesive strengths of the three adhesives were quite different from one another, in the order of PBAU ≥ PHAU ? PEAU. The influences of crystallinity and compatibility on adhesion were discussed, and the Diffusion Theory for PU-PVC systems was recommended. © 1995 John Wiley & Sons, Inc. 相似文献
998.
Benzene alkylation with propane has been studied over HZSM-5 loading 3.1–15.4 wt% Mo in continuous-flow microreactor under
350 °C and atmospheric pressure with the highest activity obtained at 6.7 wt% Mo loading. C7–9 aromatics were obtained as main products while the total amount of benzene rings kept unchanged. i-Propylbenzene and n-propylbenzene are formed primarily, while toluene, ethylbenzene, and ethyl-toluene are formed secondly from the propylbenzenes.
Catalytic performance of 6.7 wt% Mo/HZSM-5(38) partially poisoned by NH3 shows that the strong acid sites play a crucial role in the alkylation. Low SiO2/Al2O3 ratio of HZSM-5 in the Mo modified catalysts gives high propane conversion. Two hydrothermal treatment methods were applied
to the 6.7 wt% Mo/HZSM-5(38) catalyst, caused decrease of propane conversion but result in different product distribution.
A possible reaction mechanism concerning bifunctional active centers resulted from combination of loaded Mo species and strong
acid centers on HZSM-5 is proposed. 相似文献
999.
Hsi-Jen Chen Shan-Huei Yang Shun-Hsing Huang Y.P. Chyou 《Journal of the Chinese Institute of Chemical Engineers》2007
This paper addresses an integrated design of paraffin-reformer, gas separations and the electricity production with a solid oxide fuel cell (SOFC). The overall design consists of three modules. First module is a system of paraffin reformer. In this module, the paraffin feed stream is to send to a steam-reformer. In the second module, the gas separations method illustrated is the combination of a methane-permeable membrane with a pressure-swing adsorption (PSA). In the third module, the purified hydrogen is fed to the SOFC unit. To be energy efficient, this paraffin-fueled SOFC system is designed with the consideration of heat integration. The intent of this paper is to provide a possible, alternative way of cogeneration systems for refinery and petrochemical plants. 相似文献
1000.
A novel multiwalled carbon nanotube (CNTs) supported vanadium catalyst was prepared. The structure of catalyst prepared was characterized by TEM, BET, FTIR, XRD and temperature-programmed desorption (TPD) methods. The results indicated that vanadium particles were highly dispersed on the wall of carbon nanotubes. The V2O5/CNT catalysts showed good activities in the SCR of NO with a temperature range of 373–523 K. The Lewis acid sites on the surface of V2O5/CNT are the active sites for the selective catalytic reduction (SCR) of NO with NH3 at low temperatures. It was suggested that the reaction path might involve the adsorbed NH3 species reacted with NO from gaseous phase and as well as the adsorbed NO2 species. The diameter of CNTs showed positive effect on the activities of the catalysts. Under the reaction conditions of 463 K, 0.1 Mpa, NH3/NO = 1, GHSV = 35,000 h−1, and V2O5 loading of 2.35 wt%, the outer diameter of CNTs of 60–100 nm, the NO conversion was 92%. 相似文献