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微纳结构超疏水表面的浸润性分析及设计 总被引:1,自引:0,他引:1
微纳复合结构超疏水表面在防污、流动减阻、防冰等领域具有广阔的应用前景,超疏水表面主要通过设计表面化学性质和微观几何结构来获得.合理设计保持表面润湿态的稳定性是其性能发挥的关键.以"液滴-超疏水表面"系统为研究对象,基于最小能原理分析了四种稳定润湿形态,指出影响润湿状态的本征接触角和微观结构参数(相对柱距、相对柱高).推导了本征接触角的计算公式并对常见材料的本征接触角进行了讨论.结合四种润湿态方程,绘制了随着相对柱距和相对柱高的润湿云图,并将润湿云图归纳为"一点三线六区四状态".分析了相对柱距和相对柱高对浸润状态的影响,结果表明较大的本征接触角、较小的相对柱距和较大的相对柱高能够减小浸润状态发生转变的临界参数,从而拓展超疏水表面的区域范围,有利于超疏水表面的稳定性.利用文献数据验证了上述润湿云图能够准确反映出润湿形态.在上述工作基础之上总结提炼了超疏水表面设计的一般思路.研究结果可为超疏水表面的设计提供理论依据和技术基础. 相似文献
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超疏水性表面的制备及应用进展 总被引:1,自引:0,他引:1
近年来,受荷叶、水黾腿、壁虎脚等天然超疏水生物表面特性的启发,研究者们进行了大量仿生超疏水表面材料的制备及应用研究。超疏水性表面因其特殊的微纳分层结构,具有自清洁、防覆冰、防腐蚀、减阻等优异性能。本文阐述了表面润湿、疏水的基本机理,以及超疏水表面研究的理论基础,对超疏水表面制备的最新研究进展进行了综述,并揭示了研究中存在的问题。最后,介绍了超疏水表面在涂料、织物、防腐、抗菌及防雾等领域中的应用,展望了其未来的研究方向和前景。 相似文献
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电解水制氢是一种环保、简便且易于操控的制氢技术。工业化电解水制氢通常在高电流密度下进行,在制氢过程中会产生大量气泡,而气泡在电极表面聚集粘附会覆盖大量活性位点,导致电解水效率降低。因此,调控气体扩散行为对于工业电解水应用来说至关重要。近年来,超浸润材料因为其独特的润湿性能而备受关注。通过控制催化剂表面的化学组成和多尺度微纳米结构可以构建出超浸润界面材料。此类材料具有超亲水/超疏气的界面结构,有助于水相电解液的有效浸润和原位生成气泡的快速释放,从而提升催化剂的水电解性能。系统介绍了2014年至2023年期间报道的部分具有超亲水/超疏气界面结构的电解水催化剂的现状,概述其材料的合成设计策略和水电解催化性能,并对超浸润水电解催化剂的研究现状、面临的挑战和应用前景进行了总结和展望。 相似文献
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仿猪笼草效应的灌注润滑液的光滑多孔表面(SLIPS)是将润滑液如全氟聚醚、硅油、离子液体等灌注到微/纳粗糙结构基材中制备的。SLIPS材料表面可达到分子尺度的光滑,能显著减小液滴滑动角和滞后角,具有全方位疏液、自修复、透明度高、温度和压力稳定性好等诸多优点,能够高效抑制各种基材包括油脂、血液、冰以及生物膜的黏附,在自清洁涂料、海洋防污、生物医用领域具有广阔的应用前景。近年来SLIPS材料因其具有的特殊表面润湿性能而备受研究者的关注,本文详细介绍了SLIPS材料的构建机理和制备方法,包括浸润法和溶胀法等。综述了SLIPS材料在防污、促进滴状冷凝、防霜防覆冰、油水分离等方面的最新进展,并对SLIPS目前存在的问题与发展方向进行了分析和展望。 相似文献
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对液滴在界面上动态行为的研究是化学和材料领域的一个重要方向,许多先进的表面和界面技术,比如集水、防覆冰、防雾、微流体控制和传热等,均属于这一范畴.通过模仿自然界中具有特殊微纳米结构和特定化学组成的生物表面,设计并构筑相应具有特殊浸润性的仿生界面,对仿生界面材料的技术应用起到了良好的先导与示范作用.本文结合本课题组的研究... 相似文献
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表面引发聚合新进展及应用 总被引:1,自引:0,他引:1
综述了近年来聚合物刷合成与应用方面的新进展.简要介绍了利用表面引发原子转移自由基聚合(SI-ATRP)制备聚合物刷的历程和重要进展.重点论述了通过电化学、光诱导以及牺牲阳极技术、仿生合成等发展了多种表面引发ATRP新方法,基于如何将聚合物从分子尺度过渡到微米尺度的思考,实现了多尺度聚合物刷结构的制备.简要综述了聚合物刷在以下3个方面的应用研究:(1)智能驱动,利用聚合物刷构象变化,实现微悬臂驱动、辅助放大的电驱动以及仿毛毛虫运动.(2)生物润滑,利用聚合物的环境响应行为实现了对摩擦系数的调控,并发展了球刷型润滑材料.(3)表面防污,表面接枝含离子液体官能团的聚合物刷,并与仿生技术相结合,利用化学组成和结构化协同效应,得到一系列高性能低毒海洋防污界面材料. 相似文献
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用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%. 相似文献
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Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields. 相似文献
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Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction
Laurent Gavara Thomas Boisse Jean-Pierre Hénichart Adam Daïch Philippe Gautret 《Tetrahedron》2010,66(38):7544-5571
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments. 相似文献
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The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula. 相似文献
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Rebecca J. Burton Mandy L. CrowtherNeal J. Fazakerley Shaun M. FilleryBarry M. Hayter Jason G. KettleCaroline A. McMillan Paula PerkinsPeter Robins Peter M. SmithEmma J. Williams Gail L. Wrigley 《Tetrahedron letters》2013
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines. 相似文献
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KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields. 相似文献
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N. A. Nedolya 《Chemistry of Heterocyclic Compounds》2008,44(10):1165-1219
The review contains a concise historical account and information on the most significant researches undertaken by the staff
at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry
of Heterocyclic Compounds.
Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008. 相似文献
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A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL. 相似文献
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Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products. 相似文献
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A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions. 相似文献