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961.
A series of liquid chloroprene-hydroxyethyl methacrylate copolymer (CP-HEMA) modifiedepoxy resin were prepared. The effects of CP-HEMA content, curing conditions on physical pro-perties of the modified system were examined. With IR and Viscoelastocuremeter, the curing reactionrate was determined and the mechanism of the curing reaction was discussed. The effects of CP-HEMA content and curing conditions on morphology were mainly observed by scanning electronmicroscopy. 相似文献
962.
棒状钡铁氧体的反相微乳法制备 总被引:5,自引:0,他引:5
A rodlike barium ferrite precursor with an average size of 0.72~19.6 μm and aspect ratio of 2.6~8.3 has been successfully prepared in an inverse microemulsion consisting of isooctane, cetanyl trimethyl ammonium bromide (CTAB), n-C4H9OH and water with ammonia and ammonium oxalate as precipitants. On sintering at 780(C, the rodlike precursor particles could be transformed into rodlike particles of barium ferrite(BaFe12O19) with the average size and aspect ratio of 0.69~18.2 μm and 2.3~5.8, respectively. The effect of volume ratio of aqueous phase to oleic phase, the starting concentrations of metal ions and the starting concentration ratios of metal ions to precipitants were investigated. 相似文献
963.
利用四氯合金酸和N-4-甲基苯基2-吡啶甲酰胺(HL)反应,合成得到了一种新的Au(Ⅲ)配合物:二氯(N-4-甲基苯基2-吡啶甲酰胺合金(Ⅲ)[Au(L-N,N′)Cl2]。并通过元素分析、红外光谱、核磁共振谱、质谱及X-射线单晶衍射对其进行了表征。结构分析表明,Au(Ⅲ)由二个氮原子和二个氯原子配位,呈平面四方形结构。质谱研究发现,该化合物与5′-单磷酸鸟苷(5′-GMP)反应生成[Au(L-N,N′)(5′-GMP)2]。 相似文献
964.
用膨胀计法研究了西氯苯醌(CA)、苯醌(BQ)与受阻胺二异丙胺(DIPA)、2,2,6,6-四甲基-4-羟基哌啶(TMP)形成的电荷转移络合物(CTC)对偶氮二异丁腈(AIBN)引发的甲基丙烯酸甲酯(MMA)自由基聚合阻聚效应。结果表明,CA-DIPA、CA-TMP、BQ-DIPA和BQ-TMP对MMA的自由基聚合均产生较单独的醌或胺更显著的阻聚能力。其中以CA-DIPA阻聚效果更佳。比较了MMA在苯或乙腈中的溶液聚合,得类似结果。初步讨论了受阻胺-醌电荷转移络合物对MMA自由基聚合的阻聚反应机理。 相似文献
965.
966.
LiZHANG NaLI FengLinZHAO KeAnLI 《中国化学快报》2004,15(6):671-674
The interaction between heparin and neutral red was investigated by molecular spectroscopic methods. The change of all spectra suggested that positively charged neutral red had interacted with negatively charged heparin. The study of influence factors indicated that electrostatic force and hydrophobic bond might be involved in the interaction. The total binding number per disaccharide unit and intrinsic binding constant were obtained using Scatchard model. 相似文献
967.
Xin Ying ZHANG Xue Sen FAN Hong Ying NIU Jian Ji WANGSchool of Chemical Environmental Sciences Henan Normal University Key Laboratory ofEnvironmental Science Engineering of Henan Education Department Xinxiang 《中国化学快报》2003,(10)
a, a'-Bis(substituted benzylidene)cycloalkanones were efficiently prepared from cycloalkanones and benzaldehydes in [bmim][BF4] by using iron(III) chloride hexahydrate as a catalyst. It is shown that [bmim][BF4] and iron(III) chloride hexahydrate can be quantitatively recovered and be reused effectively for many times. Compared with the known methods, this novel process has the advantage of being an envkonmentally benign process together with good yields and mild reaction conditions. 相似文献
968.
电镀烧结法制备Ti/SnO2-Sb2O4电极的研究 总被引:1,自引:0,他引:1
The Ti/SnO2-Sb2O4 electrode has been prepared by the electroplate-sinter method. The effect of SbCl3 adding amount and sintering temperature on its electrode lifetime and oxygen evolution potential were investigated by means of EDX, SEM and XRD analysis. The results indicated that the electrode appeared the best performance when the SbCl3 adding amounts was 0.2g and the sintering temperature was 550℃. In optimized conditions Ti substrate was entirely covered by SnO2-Sb2O4 and the combinations among them were tight. Due to the use of electroplate method, the electrical conductivity, the oxygen evolution potential and the electrode lifetime were increased, so the elec-tro-catalytic activity and the electrochemical stability of the prepared electrode were found to be superior. 相似文献
969.
970.