溶胶-凝胶技术与固相微萃取技术的联用

固相微萃取技术的萃取效率及应用范围主要取决于其涂层的选择。传统的固相微萃取涂层热稳定性、使用寿命都不理想,溶胶．凝胶技术的引入不但增加了涂层的种类,而且增加了使用寿命,提高了其使用温度及抗溶剂冲洗能力,大大拓宽了固相微萃取技术的应用范围。     

溶胶-凝胶固相微萃取涂层的制备及特性

采用溶胶-凝胶法,将含高化学活性的四乙氧基硅烷（前驱体）与羟基硅油混和,以三氟乙酸为催化剂,经水解、缩合化学反应,形成溶胶体系,在石英纤维表面经陈化胶粒间聚合形成凝胶。将键合于石英表面上的凝胶作为固相微萃取涂层。采用FTIR红外光谱法表征了溶胶-凝胶的三维网络结构。应用溶胶-凝胶法制备的固相微萃取涂层热稳定性好,不易脱落。采用HS-SPME-GC技术萃取分析了水中的氯苯、苯、甲苯,以色谱峰高对浓度作外标曲线,在0.1~20 mg/L范围内,苯、甲苯、氯苯的线性相关系数分别为0.991 2、0.978 2、0.974 4,最低检测限分别为0.06、0.04、0.10 mg/L。实验结果表明自制的硅橡胶涂层对芳香化合物具有良好的吸附特性。     

新型固相微萃取涂层测定土壤中的邻苯二甲酸酯

建立了顶空固相微萃取与气相色谱法(HS-SPME-GC)测定土壤中邻苯二甲酸酯(PAEs)的方法.采用溶胶-凝胶法,加入自制的固相微萃取涂层,优化了固相微萃取条件,然后使用毛细管气相色谱法分离,氢火焰离子化检测器定量测定.结果表明:在70℃顶空萃取50 min,280℃下解吸5 min,加入3 g NaCl,并以一定速度搅拌的条件下,方法的线性范围为1～100μg/L,检测限为0.005 ～0.1 μg/L,相对标准偏差(RSD)为7.6％～9.2％,土壤样品的加标回收率为72.6％ ～ 112.5％.     

有机硅改性聚氨酯固相微萃取涂层的研制及应用

合成了作为固相微萃取（SPME）涂层的有机硅-聚氨酯共聚物,考察了该共聚物的物理性能;制备了萃取头并观察了萃取头的微观形貌,制作了SPME装置;用顶空萃取法对水中芳香化合物进行了萃取实验。实验结果表明：有机硅-聚氨酯共聚物固相微萃取涂层最高使用温度为250℃;萃取头涂层表面涂渍平整,涂层内硅（Si）元素分布均匀;涂层对水中苯、氯苯、硝基苯萃取的色谱峰高与浓度线性关系良好,苯：H1=1．527C1＋0．1435,R1^2=0．9875、氯苯：H2=1．746C2＋0．2679,R2^2=0．9874、硝基苯：H3=1．254C3＋1．0203,R3^2=0．9797,苯、氯苯、硝基苯的检出限分别为1．02、1．56和1.31μg·L^-1。结果令人满意。     

固相微萃取的心脏——涂层

固相微萃取是一种简单高效的新型预处理技术,涂层作为萃取头的核心部分,在萃取过程中发挥着重要作用。本文对涂层进行了概述,介绍其萃取机理、涂渍技术以及新型涂层研究发展与应用的情况。     

一种新型固相微萃取涂层的研制与应用

制备了作为固相微萃取（SPME）涂层的硅酮弹性体一聚氨酯共混物,考察了该共混物的物理性能;制作了SPME装置;用顶空萃取法对水中芳香化合物进行了萃取实验。实验结果表明：涂层最高使用温度为240℃;萃取头表面平整,涂层内硅（Si）元素分布均匀;涂层对水中苯、氯苯、硝基苯萃取的色谱峰高与浓度线性关系良好且灵敏度高,各自的检出限分别为4．22μg／L、9．36μg/L和、5．01μg/L,结果令人满意。     

固相微萃取技术在色谱分析中的研究进展

固相微萃取是近十年来发展起来的新型分离富集技术,简便快速、无污染、易于和其它技术联用。文中对固相微萃取的装置原理、涂层材料、涂渍技术、萃取方式及其在分析检测样品预处理中的应用发展方向进行了探讨。     

固相微萃取技术在色谱分析中的研究进展

固相微萃取(SPME)是近十年来发展起来的新型分离富集技术,简便快速、无污染、易于和其它技术联用。文中对固相微萃取的装置原理、涂层材料、涂渍技术、萃取方式及其在分析检测样品预处理中的应用发展方向进行了探讨。     

富勒烯硅油的制备及用做固相微萃取涂层

合成了富勒烯硅油 ,并首先将其用做固相微萃取 (SPME)涂层 ,利用顶空固相微萃取与气相色谱联用技术 (HS-SPME-GC)分析了水相中 5种邻苯二甲酸酯 ,对实验条件诸如离子强度、吸附时间和热解吸时间进行了研究 ;与商用PDMS萃取头比较 ,结果显示该萃取头对高沸点半挥发性的邻苯二甲酸酯的萃取选择性优于 PDMS。该方法的线性范围在 0 .0 0 1～ 1 0 0 0μg/L ,检出限在 8.4× 1 0 -4 ～ 2 3 .8μg/L,相对标准偏差均在 1 5 %以下     

固相微萃取在分析化学中的应用

综述了９０４上代以来在分析化学领域兴起的一门样品前处理新技术－－固相微萃取。对基本理论、实验装置及使用条件、以及在分析化学中的应用作了较全面的介绍。     

Simulation of coating phase structure formation in solid phase synthesis assisted by electron-beam treatment

The model of coating synthesis on an iron substrate under heating by a moving energy source typical for electron-beam treatment has been proposed and analyzed. The problem has been solved numerically. The time and spatial distributions of the temperature and the concentrations of the elements and compounds have been found. The regimes of coating formation from the initial material may proceed in a stationary or non-stationary, self-sustaining or forced regime, depending on the energy parameters that characterize the external source and chemical reactions, as well as on the initial concentrations of the elements and phases.     

顶空固相微萃取气相色谱法测定水中多种增塑剂

采用顶空固相微萃取气相色谱法测定了水中多种增塑剂,并考察了盐效应、萃取温度、萃取时间、热解吸时间等因素对方法灵敏度的影响,该方法的线性范围为2～1000μg/L,检出限为0.06～5.5μg/L,回收率为94.55～105.76%,RSD＜4%.     

Use of solid phase microextraction (SPME) for profiling the volatile metabolites produced by Glomerella cingulata

The profile of volatile organic compounds (VOCs) released from Glomerella cingulata using solid phase microextraction (SPME) with different fibers, Polydimethylsiloxane (PDMS), Polydimethylsiloxane/Divinylbenzene (PDMS/DVB), Carboxen/Polydimethylsiloxane (CAR/PDMS) and Divinylbenzene/Carboxen/Polydimethylsiloxane (DVB/CAR/PDMS), was investigated. C4-C6 aliphatic alcohols were the predominant fraction of VOCs isolated by CAR/PDMS fiber. Sesquiterpene hydrocarbons represented 20.3% of VOCs isolated by PDMS fiber. During the growth phase, Ochracin was produced in the large majority of VOCs. 3-Methylbutanol and phenylethyl alcohol were found in the log phase of it. Alcohols were found in cultures of higher age, while sesquiterpenes were found to be characteristic of initial growth stage of G. cingulata.     

固相微萃取-气相色谱-质谱联机测定饮用水中的嗅、味化合物

测定水样中的土味素(Geosmin)和2-甲基异冰片(MIB)时，浓缩方法主要有闭环萃取分析和固相微萃取(SPME)分析。闭环萃取分析法检出限很低，但是费用高、操作复杂且费时较长，而美国SUPELCO推出的SPME技术克服了传统的样品预处理技术的缺陷，它无需溶剂和复杂装置，能直接从液体或气体样品中采集挥发和非挥发性的化合物，可以直接在GC、GC／MS和HPLC上分析。能与任何型号的气相或液相色谱连用，有手动和自动进样两种。本文应用SPME—GC—MS，在优化了萃取头涂层种类、萃取时间、搅拌速度、离子强度、温度和溶液的pH值等条件的基础上，对水中的嗅、味化合物(土味素和2-甲基异冰片)进行测定，结果令人满意。     

固相法合成ZIF-8的表征和催化性能研究

以二甲基咪唑为有机配体,ZnO为Zn源,采用固相法制备了系列沸石咪唑酯骨架结构材料ZIF-8(S),并用XRD、FTIR、N_2吸附、SEM等手段进行了表征。主要考察了固相法制备ZIF-8的合成条件,并与常规溶剂法合成的ZIF-8(MeOH)进行了比较研究。结果表明,采用固相法可成功制备出高结晶度纯相的ZIF-8,且所制备的ZIF-8(S)与在甲醇体系中合成的ZIF-8(MeOH)相比,结晶度高,晶体粒度大,但由于其较小的外表面积,在丙二腈与苯甲醛的Knoevenagel缩合反应中的催化活性相对较低,对简单高效、环境友好的固相合成法制备ZIF-8的性能与应用研究具有重要意义。     

Characterization of zeolite basicity using probe molecules by means of infrared and solid state NMR spectroscopies

This work reviews the use of pyrrole, chloroform, methanol, as well as methoxy and nitrosonium groups generated ‘in situ’, as infrared and NMR probe molecules to characterize zeolites basicity. The main results reported in the bibliography about the correlation of the spectroscopic properties of the adsorbed molecule with the framework basicity, the host–guest interactions, and the limitations in the use of these molecules as probes for zeolite basicity are discussed. Special attention is paid to the results reported for the adsorption of pyrrole and halocarbons, most specially CHCl₃ and CHClF₂ over alkali-exchanged FAU-type zeolites using IR and NMR spectroscopies.     

Silk fibroin nanofibers electrospun on glass fiber as a potential device for solid phase microextraction

The electrospinning technique was applied to coat fused silica fibers with regenerated silk fibroin (RSF) nanofibers, aiming to build a device applicable for solid phase microextraction analysis. The device was characterized by attenuated total reflectance infrared spectroscopy, thermal analyses (differential scanning calorimetry and thermogravimetric analysis), and scanning electron microscopy, and employed to extract/desorb isopropyl alcohol (IPA) from the headspace of an IPA aqueous solution. The electrospun coating proved to be thermally stable up to 250°C, even after 4 h of exposure to this temperature. A 2² factorial experimental design was used to evaluate the flow rate of the polymer solution and the distance between capillary tip and collector on the mean RSF fiber diameter. A low flow rate (0.20 mL h^?1) and large capillary tip‐to‐collector distance (12 cm) yielded fibers with mean diameter of (304 ± 46 nm). The nanofibers were heated to 250°C, simulating the conditions in the injector of a gas chromatograph (GC). In these conditions, the RSF nanofibers were found not to melt even after 4 h of exposure to heat, although slight structural damage was detected. Preliminary assays using the as‐constructed device built under optimized electrospinning conditions (0.20 mL h^?1 and 12 cm) were performed in a GC by contact with the headspace of a 50 ppm IPA solution to determine the extraction and desorption times. The results indicated that the extraction process stabilized after 20 min of contact with the headspace of the IPA solution. The desorption process was complete after 10 min at 140°C. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41717.     

AI2O3-SiO2:Tb3+发光材料的溶胶--凝胶合成及发光特性

采用溶胶－凝胶（sol-gel)法低温合成了Al2O3-SiO2:Tb^3 绿色发光材料，研究了Al2O3和SiO2配比，Tb^3 浓,烧结温度，烧结时间对光强度的影响，讨论了发光体的发光特性。