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991.
环氧硅油改性聚氨酯弹性体的制备与表征   总被引:1,自引:0,他引:1  
以2,4-甲苯二异氰酸酯(TDI)、聚氧化丙烯醚二醇(PPG-1000)为主要原料,以环氧硅油为改性剂,以3,3'-二氯-4,4'-二氨基二苯甲烷(MOCA)为扩链剂,制备了一系列硅油改性聚氨酯弹性体(PUE),并对试样进行了红外光谱、力学性能和耐热老化性能测试.结果表明,添加环氧硅油的PUE的力学性能变差,但老化后的...  相似文献   
992.
合成条件对PAA/MMT高吸水性树脂性能的影响研究   总被引:2,自引:0,他引:2  
崔笔江  张小红 《广东化工》2011,38(3):103-104,61
聚合反应中影响树脂吸水性能的因素有很多,文章以单因素考察法对PAA/MMT高吸水性树脂的制备过程中的影响因素进行了研究主要讨论了交联剂量、分散剂量、引发剂量、中和度、反应温度等因素对树脂吸水性能的影响,为优化实验条件提供初步的依据.  相似文献   
993.
This study investigated the differences between different large colour‐difference (LCD) data sets (with a mean ΔE value about 10). Six data sets were studied. For each data set, various CIELAB based colour difference models were derived to fit the data. These models were compared to shed light on the difference between the different data sets. It was found that all data sets have very similar characteristics except for the Munsell data. Detailed investigation showed that the discrepancy is mainly due to the balance between the lightness and chromatic differences used previously for the Munsell data set. It was found that one unit of Munsell Value appears to be three times as large colour difference as one unit of Munsell Chroma at least under the experimental conditions for the data sets studied here. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2011  相似文献   
994.
The influence of operational parameters and anode materials on degradation kinetics, mineralization current efficiency, and energy consumption for electrochemical oxidation of phenol was studied. Phenol elimination follows pseudo‐first‐order kinetics in most cases except for the Ti/RuO2 anode with a phenol concentration of 500 mg L–1, where pseudo‐zero‐order kinetics is observed. The total organic carbon removal by a Ti/Sb‐SnO2 anode follows pseudo‐first‐order kinetics in contrast to pseudo‐zero‐order kinetics by Pt and Ti/RuO2 anodes. For a certain anode, a higher current or voltage input results in a higher reaction rate. With a Ti/Sb‐SnO2 anode, the highest current efficiency and the lowest energy consumption are obtained, but the current efficiency decreases (increases for energy consumption) quickly as the reaction is prolonged due to the reduction of organics.  相似文献   
995.
崔小安  喻江 《贵州化工》2002,27(1):43-44
介绍仪表空气干燥器功能、试车运行情况及在生产中所起的作用和使用后收到的效果。  相似文献   
996.
The crystallization behavior of oligoester blends prepared from crystalline poly(hexanediol adipate) (PHA) and amorphous poly(ethylene diethylene glycol adipate) (PEDEA) was studied using POM, WAXD, and DSC. The crystal form of both PHA and the blends are spherulites. The crystallinity, melting enthalpies, and crystallization rate increased with increased PHA content in the blends. Two sharp diffraction peaks of each blend were detected at the same position, where, respectively, 2θ = 21.3° and 24.1°. The research on the crystallization kinetics showed that the Avrami exponent of all the oligoester blends is approximately 4. It was demonstrated that the crystallization mechanism of PHA is not disturbed by amorphous PEDEA. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1363–1368, 2002; DOI 10.1002/app.10268  相似文献   
997.
Two new poly(p‐phenylenevinylene) (PPV) derivatives containing oxadiazole moiety (OXA‐PPV1 and OXA‐PPV2) were synthesized by the Wittig condensation polymerization reaction. Their thermal and light‐emitting properties were investigated. The single‐ and triple‐layer electroluminescent (EL) devices with configurations of ITO/polymer/Al and ITO/polymer/OXD‐7/Alq3/Al were fabricated. They exhibited blue emission at 470 nm for OXA‐PPV1 and green emission at 560 nm for OXA‐PPV2. The turn‐on voltages of triple‐layer device were 11 V for OXA‐PPV1 and 8 V for OXA‐PPV2. The triple‐layer EL devices showed much better performance than did the single‐layer devices. The spectra indicated energy transfer occurred from segments of side chain to polymer backbone. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 422–428, 2002  相似文献   
998.
999.
The effects of surfactant on the solvent extraction in leaching sphalerite were investigated. It is found that sodium dodecyl sulfonate is the effective surfactant in improving the zinc recovery from sphalerite in the aqueous FeCl3-HCl-tetrachloroethylene system. Through the measurements of surface tension and viscosity of the sphalerite slurry modified with different surfactants, it is concluded that sodium dodecyl sulfonate in the concentration range of 0.05 to 0.2g L-1 can improve the viscosity of sphalerite slurry in the water, decrease the surface tension of leaching solution, prevent the aggregation of ore particles, and give very high zinc extraction .  相似文献   
1000.
4BS染料光催化降解动力学   总被引:3,自引:7,他引:3       下载免费PDF全文
尹晓红  辛峰  张凤宝 《化工学报》2002,53(5):528-532
在间歇式淤浆床反应器中 ,以TiO2 为催化剂、高压汞灯为光源进行了 4BS染料光催化降解的动力学研究 .通过改变催化剂用量、反应时间及反应物初始浓度等条件 ,确定适宜的催化剂用量和溶液的 pH值 .在此基础上得到了消除固液混合及外扩散影响后的反应动力学方程 ,为反应器设计提供了必要的理论依据 .  相似文献   
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