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4—(2—噻唑偶氮)—1,3—二氨基苯的合成及性能的研究 总被引:3,自引:0,他引:3
新试剂4-(2-噻唑偶氮)-1,3-二氨基苯的合成及其质子化行为的研究,用光度法测得试剂的三级酸离解常数为:pK■=5.6,pK■=0.2,pK■=4.4。考察了试剂的分析性能。 相似文献
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采用接触角测定法研究了固体火箭发动机用三元乙丙绝热层的表面酸碱性质。研究结果表明,三元乙丙绝热层的表而呈现Lewis碱性,且发现经过特定热处理过程后的绝热层表面碱性变得更强。应用“单极性”理论及其数据处理方法.定量求出了多批次三元乙丙绝热层的表面酸碱自由能参数γs^+、γs^-以及表面自由能的色散分量γs^LW。 相似文献
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不同预处理方法对稻秸纤维表面性质的影响 总被引:1,自引:0,他引:1
通过对稻秸原料进行水热、酸碱和冷等离子体预处理,分析了纤维表面的浸润性及表面自由基浓度的变化。研究表明,经水热及酸碱预处理后,纤维与水的接触角为90o,稻秸纤维的浸润性改善不明显,经冷等离子改性后,稻秸纤维表面浸润性改善非常明显。水热及乙酸处理有利于提高稻秸纤维的表面自由基浓度,碱处理则降低了稻秸纤维的表面自由基浓度。 相似文献
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杜以军蒋金华等 《玻璃钢/复合材料》2014,(3):27-31
为定量了解Vectran纤维的耐酸碱性能,为其实际应用提供必要的理论参考,采用硫酸和氢氧化钠溶液对其进行了处理,并测试处理前后纤维的失重率、断裂强度和表面形貌的变化。结果表明,酸碱处理后,Vectran纤维的质量损失率相差不大,只有在浓硫酸中纤维的腐蚀情况比较严重;拉伸试验中,Vectran长丝的强力受酸碱处理的影响不大,只有浓硫酸对其有致命的影响;SEM显示酸碱处理使Vectran纤维表面产生纵向沟槽,沟槽的密度和深度与酸碱的浓度和处理时间有关,其中硫酸的处理效果更为明显。 相似文献
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综述了开关型表面活性剂的性能及应用现状.其中电化学开关表面活性剂主要介绍了二茂铁类,同时还包括吡嗪类和二硫基类;光开关型表面活性剂主要介绍了偶氮苯基和苯乙烯基表面活性剂;酸碱开关表面活性剂介绍了AMI,AFD4和PLLA/PEG - PSD; CO2开关表面活性剂主要介绍了长链烷基脒的乳化性能及其在乳液聚合中的应用;同时介绍了NIPAM - co - PEGMa,亚胺类温度开关表面活性剂.展望了开关型表面活性剂的应用领域和发展趋势. 相似文献
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低温等离子体对F24表面处理的研究 总被引:7,自引:1,他引:6
本文通过失重、交联.接触角、表面能及剪切强度测定等方法研究了在不同等离子理条件下,F24在处理前后表面结构性能的变化.结果表明,处理后的F24润湿性和粘接性能有明显改善,较未处理时接触角下降约20°左右,剪切强度较未处理的提高二倍多. 相似文献
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In this paper the effects of surface energy and surface roughness on the deposition of calcium sulphate during convective and subcooled flow boiling heat transfer to aqueous CaSO4 solutions are studied. The surfaces of several test heaters have been treated by Ion Beam Implantation, Unbalanced Magnetron Sputtering, Mixed Sputtering and Plasma Arc Deposition to reduce surface energy. One heater was electropolished to reduce surface roughness and one heater was etched by an electrochemical method to increase surface roughness. Fouling runs with these heaters, and with an untreated surface as control, were carried out at different heat fluxes, flow velocities and salt concentrations. The results show that heat transfer surfaces with low surface energy experienced significantly reduced fouling, while electropolishing did not have a notable beneficial effect. The combined effect of reduced surface energy and flow velocity on fouling reduction is considerably stronger than previously reported for pool boiling. 相似文献
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《大分子材料与工程》2017,302(11)
Biomaterials for in vivo application should induce positive interaction with various histocytes and inhibit bacteria inflection as well. Cells and/or bacteria response to the extracellular environment is therefore the basic principle to design the biomaterials surface in order to induce the specific biomaterial–biological interaction. Polyhydroxyalkanoate (PHAs) are of growing interests because of their natural origin, biodegradability, biocompatibility, and thermoplasticity; however, quite inert and intrinsic hydrophobic characteristics have hindered their extensive usage in medical applications. Surface modification of PHAs tailors the chemistry, wettability, and topography without altering the bulk properties, and introduces specific proteins/peptides and/or antibacterial agents to mediate cell–matrix interactions. This review describes the recent developments on the surface modification of PHAs to construct cell compatible and antibacterial surfaces. 相似文献
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《Journal of Adhesion Science and Technology》2013,27(10):1051-1063
Oxygen plasma treatment as a surface functionalization technique is discussed. Oxygen-containing functionalities were introduced on the surface of high- (HDPE) and low-density polyethylene (LDPE) by glow discharge. The number of surface hydroxyl groups was increased by a post-discharge wet treatment in a reducing solution. The effects of the substrate nature, the discharge parameters, and the post-discharge wet treatment on the surface functional groups are discussed, and the effectiveness of functionalized surfaces on the yield of coupling reactions is shown. 相似文献
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简述了大分子表面改性剂添加到聚烯烃基体中时接触介质的诱导作用和聚烯烃基体结晶的异质排斥作用及其相对分子质量、链节的柔顺性和与基体的相容性对其表面富集的影响。提出大分子表面改性剂设计合成的基本原则:化学结构和使用环境相匹配、憎水基功能团和亲水基功能团相适应、使用效率和功能持久性相平衡。介绍了大分子表面改性剂合成的主要方法。 相似文献
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David A. King 《Topics in Catalysis》1994,1(3-4):315-324
The rigour and wide ranging power of experimental surface science techniques developed in recent years has transformed our ability to understand surface processes. In this brief but broad ranging review, these developments are illustrated with examples of new results in: structure determination; calorimetric measurements of adsorption heats; kinetics and dynamics of adsorption and surface catalysed reactions; and the control of surface reactions. 相似文献
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高速气流冲击式粉体表面改性装置——HYBRIDIZATION系统及应用 总被引:4,自引:0,他引:4
利用高速气流冲击法进行粉体/粉体系表面改性技术,是迄今为止各种粉体材料开发中最为引人注目的技术之一。HYBRIDIZATION(下称HYB)系统是利用高速气流冲击法对微粉体进行干式/机械化处理,是使材料复合化的最实用的装置,可对各类有机物、无机物、金属等进行广泛组合,通用性很强,适用于许多行业领域。从本文所述的系统构成、型式,有关的典型球形化处理的运转特性,利用复合化高温粉体测定被处理粉体表面温度,利用颜料改变色调等的处理特点及该系统的适用性等(一部分是从已发表的学术论文及专利上摘录的),可以说明HYB系统的概况。 相似文献