聚氯乙烯塑料中增塑剂的气相色谱/质谱法分析

采用超声波提取技术，提取聚氯乙烯塑料中邻苯二甲酸二丁酯和邻苯二甲酸二辛酯两种增塑剂，以气相色谱／质谱单离子监视法定量测定，外标法定量。本方法简便、快速、准确，适用于聚氯乙烯塑料原料及其制品中邻苯二甲酸二丁酯和邻苯二甲酸二辛酯的测定。     

固相光催化降解废弃塑料

“白色污染”已成为目前普遍关注的一个全球性环保课题。将光催化剂掺入到塑料中制备出环境友好的可光降解复合塑料,利用其光催化活性可以使废弃塑料在太阳光的照射下发生有效降解,是解决“白色污染”问题的有效途径之一。本文综述了近年来固相光催化降解废弃塑料的研究进展,介绍了光催化剂TiO₂、ZnO、α-FeOOH和H₃PW₁₂O₄₀对废弃塑料的固相光催化降解效率及各种复合塑料的光催化降解机理,阐述了对光催化剂进行表面改性可以改善其在聚合物中的分散性,以及对光催化剂进行修饰可以提高其对可见光的吸收,从而提高复合塑料的固相光催化降解活性及对太阳光的有效利用率。最后,展望了固相光催化技术在废弃塑料处理领域的应用前景。     

Identification and determination of (+)-sesamin in Semen Cuscutae by capillary GC and GC-MS

(+)-Sesamin has been found to have pharmacological effect which can improve activity, prevent aging and has the effect of antihypertension 1-2. Figure 1 shows its chemical structure. (+)-Sesamin has been known to be abundant in sesame originally, but our previous study shows that (+)-sesamin also presents in a Chinese herbal medicine Semen Cuscutae3-4. Gas chromatography (GC) and gas chromatography - mass spectrometry (GC-MS) have been applied for the determination and identification of (+…     

Capillary GC and GC-MS of porphyrins and metalloporphyrins

Summary Despite their inherent low volatility, a wide range of alkyl porphyrins and their various metallo-derivatives have been successfully analysed by gas chromatography on wall coated open tubular (WCOT) capillary columns. As a result of their superior peak shape (comparable ton-alkanes of similar retention times) and relatively low Kovat's retention indices (3300–3900), the bis(trialkylsiloxy)Si(IV) derivatives offer the greatest potential for the GC analysis of geological mixtures of alkyl porphyrins. Similar derivatives of porphyrins of biomedical importance, possessing polar side chains, are also amenable to GC and GC-MS analysis.Presented at the 14th International Symposium on Chromatography London, September, 1982     

Environmental Analysis of Cypermethrin and its Degradation Products After Forestry Applications

Abstract

Cypermethrin and alphamethrin ([1R, cis, αS]- and [1S, cis, αR]-cypermethrin) are pyrethroid insecticides used in agriculture, forestry, and public health hygiene. After forestry applications of cypermethrin against bark beetles diastereo- and enantioselective analyses of pyrethroid residues are performed by gas chromatography (GC) with electron capture (ECD) and mass spectrometric (MS) detection, or by achiral and chiral high performance liquid chromatography (HPLC). The major soil metabolites of cypermethrin, i.e. 2,2-dimethyl-3-(1,1-dichlorovinyl)-cyclopropylic acid and 3-phenoxybenzoic acid, are analyzed as methyl esters by GC-MS with electron-impact (EI) ionization. On spruce bark cypermethrin persists several months as surface films of 1 μg/cm^2. In soil it is detected as long as seven months after treatment at levels of 0.15–0.7 μg/g. Sunlight-induced cis, trans isomerization on bark and leaves results in an excess of trans-cypermethrin isomers. In soil cis-cypermethrin isomers are more persistent than their corresponding trans-isomers. Enantioselective HPLC demonstrates chiral discrimination of a pair of trans-cypermethrin enantiomers. Analysis of soil metabolites is less meaningful since traces of the investigated products are formed from pyrethroid residues during the extraction and derivatization procedures.     

气相色谱/质谱法鉴定黑芝麻中黑色素的结构类型

 为获得天然高分子化合物黑芝麻中黑色素的分子结构信息 ,对其进行碱熔降解 ,然后对降解产物进行硅烷化衍生 ,再利用气相色谱 /质谱联用分析 ,结果发现产物中含有儿茶酚、对苯二酚和儿茶酸 ,从而证明黑芝麻中的黑色素具有儿茶酚型黑色素的结构特征。     

山楂挥发性化合物的气相色谱-质谱分析

采用蒸馏－萃取法收集山楂果的挥发性化合物,通过气相色谱及气相色谱／质谱分析,鉴定了３２种化合物,占总峰面积的６１％～６８％。其中主要的１０种化合物是顺－３－己烯醇、顺－３－乙酸己烯酯、α－萜品醇、糠醛、己醇、乙酸己酯、壬醛、柠檬醛、３－戊烯－２－酮,反－２－癸烯醛等。     

有机硅混合环硅氧烷色谱－质谱联用定性分析

通过色谱－质谱联用定性地分析了二甲基硅氧烷和甲基乙烯基硅氧烷混合环体的色谱、质谱特征。讨论了甲基乙烯基环四硅氧烷质谱的离子分裂方式,测定了各种有机环硅氧烷的色谱保留时间（ｔＲ）,建立了有机硅混合环体色谱－质谱的定性分析方法。     

气相色谱法分离检定血中八种氨基甲酸酯

采用国产Ｃ＿１８往固相提取血中八种氨基甲酸酯,用乙酸乙酯洗脱,用气相色谱分离检定,用气相色谱／质谱进行确证。此法灵敏度为１～２μｇ／ｍＬ血,最低检出限为２０～４０ｎｇ,回收率在６２～９２％之间。     

芬顿试剂对田菁胶的氧化降解

考察了芬顿试剂对田菁胶的氧化降解行为. 系统研究了H_2O_2和Fe~(2+)用量、温度和降解时间对田菁胶粘度的影响. 结果表明,H_2O_2和Fe~(2+)合适的体积比为2:1. 在较低的温度(25 ℃)和较短的时间(20 min)内芬顿试剂就能使田菁胶粘度下降90%以上. 另外,pH值的变化对其降解性能影响不大,显示了较好的降解效果.     

A sensitive capillary GC-MS method for analysis of topiramate from plasma obtained from single-dose studies

Topiramate (Topamax®) is an antiepileptic medication used as adjunctive and monotherapy in patients with epilepsy and for migraine prophylaxis. A GC‐MS assay was developed that was capable of detecting topiramate plasma concentrations following a single rectal or oral dose administration. Topiramate plasma samples were prepared by solid‐phase extraction and were quantified by GC‐MS analysis. The topiramate standard curves were split from 0.1 to 4 µg/mL and from 4 to 40 µg/mL in order to give a more accurate determination of the topiramate concentration. The accuracy of the standards ranged from 94.6 to 107.3% and the precision (%CV) ranged from 1.0 to 5.3% for both curves at all concentrations. The %CV for quality controls was <7.6%. The assay is both accurate and precise and will be used to complete future pharmacokinetic studies. Copyright © 2012 John Wiley & Sons, Ltd.     

芬顿试剂对田菁胶的氧化降解行为研究

本文考察了芬顿试剂对田菁胶的氧化降解行为。系统研究了H2O2和Fe2+用量、温度和降解时间对田菁胶粘度下降百分率的影响,并简单讨论了芬顿试剂对田菁胶的氧化降解机理。结果表明,H2O2和Fe2+的合适用量之比为2︰1。另外,只需较低的温度(25 ℃)和较短的时间(20 min),芬顿试剂就能使田菁胶粘度下降90%以上,显示了较好的降解效果。     

GC-MS法检测牛肉中拟除虫菊酯的残留量

建立了柱层析法/气相色谱(GC)-负化学离子源(NCI)质谱检测牛肉中7种常用拟除虫菊酯杀虫剂残留的方法.样品经乙腈提取,通过中性氧化铝层析柱净化后,再由气相色谱-负化学离子源质谱选择离子监测技术(SIM)进行测定.7种菊酯类农药标准溶液在10～1 000 μg/L范围内线性关系良好,r2均大于0.997,在10、20...     

治理塑料废弃物新技术途径探讨--专论可降解塑料的研究开发

综述了可降解塑料的研究开发现状及其进展。可降解塑料的降解时控性研究，合成，加工工艺改进以及降低成本的研究，可控光－生物降解的合成降解性研究和一次性使用塑料实用性研究，仍是今后需要深入探讨的重要研究课题。     

微波辅助衍生化GC-MS法测定食用油中的脂肪酸

利用微波技术,研究了用ＫＯＨ－甲醇,Ｈ２ＳＯ４－甲醇－甲苯、ＨＣｌ－甲醇等不同体系对食用油中的脂肪酸进行了衍生化,系统地比较了它们的优劣势,以及适合的分析对象,在１ｍｉｎ内完成衍生物生化反应,选用正庚烷代替传统方法的苯＋石油醚作为脂肪酸甲酯蝗提取剂,与传统消解及衍生化方法相比,具有节省溶剂,省时,易于操作等特点。     

GC-MS法测定氧化型染发剂中的苯二胺

建立了气相色谱-质谱同时测定氧化型染发剂中邻苯二胺、间苯二胺和对苯二胺的方法。以乙酸乙酯提取氧化型染发剂中苯二胺,用气相色谱-质谱方法进行定性和定量分析。该方法对氧化型染发剂中的3种苯二胺的检出限为20 mg/kg,线性范围为0.2~10 mg/L,线性相关系数为0.999 2~0.999 9。方法的回收率为75%~110%,满足氧化型染发剂中3种苯二胺检测的需要。     

微波消解衍生化气相色谱-质谱法测定鲨鱼软骨中的脂肪酸

 研究了用微波技术消解衍生化气相色谱 质谱法 (GC MS)快速测定鲨鱼软骨中脂肪酸的分析方法。用正交设计试验优化消解衍生化条件 ,以盐酸 甲醇 (体积比为 1∶4)体系作消解衍生化溶液 ,在 60 0W微波功率作用下加热 4min进行样品的前处理 ,将样品的消解、脂肪酸的衍生化及脂肪酸甲酯的萃取融于一体。方法具有灵敏度高、省时、省试剂、操作方便等特点。该法适用于大批量固体样品中脂肪酸的测定。