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61.
62.
阴—阳离子表面活性剂复配研究与应用 总被引:19,自引:3,他引:19
综合介绍了阴-阳离子表面活性剂复配体系在各种物化性能的增效效应,例如降低表面张力的效能,表面张力的效率,降低临界胶束浓度的能力,改善表面吸附的能力,以及这些增效效应在去污,增溶,泡沫,润湿,乳化等方面的应用。讨论了提高阴-阳离子表面活性剂之间的可配伍性之对策,诸如采用非等摩尔比复配,在离子型表面活性剂中引入聚乙烯链及加入非离子或两性表面活性剂进行调节等手段以优化配方性能和提高综合经济效益。总结了阴-阳离子表面活性剂复配体系用于洗涤用品的可行性配方技术,即采取无机助剂,水溶性有机高聚物或非离子表面活性剂包裹阳离子表面活性剂的措施。 相似文献
63.
64.
新型Gemini阳离子表面活性剂的合成和性能(1):从长链烷基二甲基胺及其盐酸盐和环氧氯丙烷合成双烷基双季铵盐阳离子 总被引:37,自引:0,他引:37
概述了从长链烷基二甲基叔胺及其盐酸盐和环氧氯丙烷或其他连接剂在温和条件下合成新型双烷基双季铵盐型阳离子表面活性剂的方法,产品的表面活性以及烷基链长、连接基团结构对产物表面活性的影响。 相似文献
65.
阳离子型及两性絮凝剂现状与发展方向 总被引:26,自引:4,他引:26
阳离子型高分子絮凝剂及两性絮凝剂具有许多优点,近年来得到国内外学者的广泛重视和开发应用。本文通过对几种阳离子型高分子絮凝剂及两性高分子絮凝剂的介绍,分析了它们的发展现状与方向。 相似文献
66.
《大分子材料与工程》2017,302(11)
Azopolymers are highly versatile materials due to their unique photoresponsive properties. In this contribution, a novel azo‐modified epoxy network is synthesized by cationic homopolymerization with boron trifluoride monoethylamine (BF3.MEA) complex as initiator. The effect of the addition of a fixed content of amino‐functionalized azo chromophore, Disperse Orange 3, into the polymer matrix is studied in detail. First of all, the thermal curing cycle is optimized by means of differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) measurements. Then, the resulting bulk azo‐modified epoxy networks are characterized by means of thermogravimetric analysis (TGA), FTIR, DSC, UV–vis spectroscopy, and rheological measurements. Finally, the optical response of thin films of these materials is determined. The results evidence that azo‐modified epoxy networks obtained by cationic polymerization with optimized curing cycle display high T g values, high maximum photoinduced birefringence, fast writing speed, and exceptionally high remnant anisotropy. Therefore, this material is a promising candidate to be used for optical storage applications. 相似文献
67.
Dr. Irina Novosjolova Dr. Scott D. Kennedy Dr. Eriks Rozners 《Chembiochem : a European journal of chemical biology》2017,18(21):2165-2170
The development of nucleic acid base-pair analogues that use new modes of molecular recognition is important both for fundamental research and practical applications. The goal of this study was to evaluate 2-methoxypyridine as a cationic thymidine mimic in the A–T base pair. The hypothesis was that including protonation in the Watson–Crick base pairing scheme would enhance the thermal stability of the DNA double helix without compromising the sequence selectivity. DNA and peptide nucleic acid (PNA) sequences containing the new 2-methoxypyridine nucleobase (P) were synthesized and studied by using UV thermal melting and NMR spectroscopy. Introduction of P nucleobase caused a loss of thermal stability of ≈10 °C in DNA–DNA duplexes and ≈20 °C in PNA–DNA duplexes over a range of mildly acidic to neutral pH. Despite the decrease in thermal stability, the NMR structural studies showed that P–A formed the expected protonated base pair at pH 4.3. Our study demonstrates the feasibility of cationic unnatural base pairs; however, future optimization of such analogues will be required. 相似文献
68.
本文应用了阳离子染料在ECDP纤维上进行了一系列的染色性能试验,着重从热力学、动力学角度对染色机理、染色性能、工艺条件进行了探讨.为选择合适的ECDP纤维的染整加工条件提供了一定的理论依据. 相似文献
69.
Dr. Erik Strandberg Dr. Parvesh Wadhwani Dr. Jochen Bürck Dr. Patrick Anders Dr. Christian Mink Dr. Jonas van den Berg Raffaele A. M. Ciriello Dr. Manuel N. Melo Prof. Dr. Miguel A. R. B. Castanho Prof. Dr. Eduard Bardají Prof. Dr. Jakob P. Ulmschneider Prof. Dr. Anne S. Ulrich 《Chembiochem : a European journal of chemical biology》2023,24(4):e202200602
BP100 is a cationic undecamer peptide with antimicrobial and cell-penetrating activities. The orientation of this amphiphilic α-helix in lipid bilayers was examined under numerous conditions using solid-state 19F, 15N and 2H NMR. At high temperatures in saturated phosphatidylcholine lipids, BP100 lies flat on the membrane surface, as expected. Upon lowering the temperature towards the lipid phase transition, the helix is found to flip into an upright transmembrane orientation. In thin bilayers, this inserted state was stable at low peptide concentration, but thicker membranes required higher peptide concentrations. In the presence of lysolipids, the inserted state prevailed even at high temperature. Molecular dynamics simulations suggest that BP100 monomer insertion can be stabilized by snorkeling lysine side chains. These results demonstrate that even a very short helix like BP100 can span (and thereby penetrate through) a cellular membrane under suitable conditions. 相似文献
70.
A novel phenacyl anilinium salt, N-phenacyl, N,N-dimethylanilinium hexafluoroantimonate, (PDA), has been synthesized and used as photoinitiator for cationic polymerization of cyclohexene oxide (CHO), butyl vinyl ether (BVE) and N-vinyl carbazol (NVC). Plausible mechanism of the photoinitiation involves the decay of the excited PDA with both heterolytic and homolytic cleavages of carbon-nitrogen bond. Thus, phenacylium cations formed directly or subsequent intermolecular electron transfer, respectively, initiate the polymerization. 相似文献