选择性

Abstract(#br)The PDMS mixed matrix membranes containing 10-μm sized zeolite were prepared, characterized, and tested on the pervaporation (PV) performance for ethanol–water solutions. We found that the membrane with the zeolite mixed after the PDMS cross-linker addition (“post-addition”) was more effective at removing ethanol from the aqueous mixtures than the pristine PDMS and the PDMS–zeolite membrane made with the zeolite addition prior to the PDMS cross-linker addition.

AbstractTwo microporous organic frameworks based on adamantane (hereafter denoted as MF-Ads) were fabricated through Sonogashira-Hagihara coupling polycondensation of aryl halides and alkynes. Results show that both types of MF-Ad networks had similar porous properties and exhibited excellent CO2 uptake capacity (72.5 cm3 g−1) and CO2/N2 selectivity (59.1) at 273 K and 1.0 bar. Taking advantage of the superhydrophobic wettability of the resulting MF-Ad networks, wire mesh scaffolds were used to fabricate superhydrophobic films with polydimethylsiloxane (PDMS) acting as a binder.

Optimization of Headspace Sampling Using Solid Phase Microextraction For Volatile Organic Acids in Different Tobacco TypesSolid-phase microextraction(SPME);volatile organic acids;Selectivity;tobacco;adsorption efficiency;A Solid-phase micro extraction(SPME) was evaluated as a tool for headspace sampling of tobacco samples. Several experimental parameters (sampling temperature, pH, and type of SPME fibers) were optimized to improve sampling efficiency in two aspects ; maximum adsorption and selective adsorption of volatile organic acids onto SPME fibers.

Preparation and Permeation Characteristics of PDMS-b-PMMA Copolymer MembranePDMS-b-PMMA;membrane;permeability;selectivity;ATRP;In this research, polydimethylsiloxane-polymethylmethacrylate (PDMS-PMMA) block copolymer was synthesized from polydimethylsiloxane (PDMS) and methylmethacrylate (MMA) monomer using atom transfer radical polymerization (ATRP). The synthesis characterization of the PDMS-b-PMMA copolymer membrane was carried out by a FT-IR, $^1H$-NMR, GPC and DSC.

搅拌棒吸附萃取( SBSE )是一种常用的无溶剂样品制备方法，广泛应用于多种非极性溶质的取样和预富集。一种典型的SBSE搅拌棒由聚二甲基硅氧烷( PDMS )薄膜组成，涂复在带有磁芯的玻璃夹套上。取样通过直接浸泡或将搅拌棒暴露在样品的顶空进行。迄今为止，大多数已报道的SBSE装置都采用PDMS作为吸附剂，有一些商业上可替代的SBSE涂层(如聚乙二醇和聚丙烯酸酯)，这限制了SBSE对极性和亲水性更强的溶质的适用性。对更多选择性萃取的兴趣是最近开发新型SBSE涂层的推动力，特别是那些对更多极性溶质具有选择性的涂层。近十几年来，利用不同的制备方法，包括表面黏附、分子印迹、溶胶凝胶技术、固载体和溶剂交换等，大量新型SBSE涂层被引入。为此，人们使用了一系列纳米和微碳基材料、功能聚合物、金属有机骨架( MOFs )和无机纳米粒子。其中一些SBSE涂层表现出更高的热稳定性和化学稳定性，并具有更宽的选择性。本审查旨在总结过去六年报告的这些重大发展，特别注意新材料和选择性，以扩大SBSE的潜在应用。

搅拌棒吸附萃取( SBSE )是一种常用的无溶剂样品制备方法，广泛应用于多种非极性溶质的取样和预富集。一种典型的SBSE搅拌棒由聚二甲基硅氧烷( PDMS )薄膜组成，涂复在带有磁芯的玻璃夹套上。取样通过直接浸泡或将搅拌棒暴露在样品的顶空进行。迄今为止，大多数已报道的SBSE器件都采用PDMS作为吸附剂，并有少量可替代的商用SBSE涂层(如聚乙二醇和聚丙烯酸酯)，这限制了SBSE对更多极性和亲水性溶质的适用性。对更多选择性萃取的兴趣是最近开发新型SBSE涂层的推动力，特别是那些对更多极性溶质具有选择性的涂层。近十几年来，利用不同的制备方法，包括表面黏附、分子印迹、溶胶凝胶技术、固载体和溶剂交换等，大量新型SBSE涂层被引入。为此，人们使用了一系列纳米和微碳基材料、功能聚合物、金属有机骨架( MOFs )和无机纳米粒子。其中一些SBSE涂层表现出更高的热稳定性和化学稳定性，并具有更宽的选择性。本审查旨在总结过去六年报告的这些重大发展，特别注意新材料和选择性，以扩大SBSE的潜在应用。

疏水深亚共晶溶剂( HDES )被认为是一类比较新颖的溶剂，它显示出完美的特性将它们结合到渗透汽化膜中。复合HDES膜提供了比聚合物膜更快的分子扩散速度的分离介质，结合了液体和聚合物膜的最佳性能，具有很高的选择性和耐破压力。本工作采用HDES利多卡因-麝香草酚( Lidol )和CH3 ( CH2 ) 8COOH-麝香草酚( Decadol )制备的膜进行渗透汽化分离丙酮-丁醇-乙醇混合液( ABE )与水溶液离出来，用两种聚二甲基硅氧烷( PDMS )平PDMS )平板膜。复合膜对丁醇/水的选择性比作为对照的单一PDMS层膜有所改善。Lidol基膜得到的丁醇总通量为2.93  ×  10 - 3 [ kg m–2 hr–1 ]，水总通量为1.22  ×  10 - 4 [ kg m–2 hr–1 ]，丁醇/水2，而对照膜的选择性值为6。由复合膜得到的结果在分离丁醇和ABE溶液中表现出更高更稳定的性能。选择性的提高可以通过PDMS涂层与HDES层的协同作用来解释。