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Chinese Journal of Chemistry 1999年第2期17卷 155-164页

作者：印春生潘忠孝易忠胜李志良张懋森 Department of Applied Chemistry University of Science and Technology of ChinaHefei Anhui 230026 China Department of Applied Chemistry Guilin Institute of Technology Guilin Guangxi 541004 China Institute of Chemistry and Chemical Engineering ICP Hunan UniversityChangsha Hunan 410082 China

Systematic studies are made on application of chemometrics to chemical modeling and/or molecular modeling as well as the regularity of retention index for gas chromatography (GC). A set of novel molecular graph theoretical parameters, called the molecular distance-edge (MDE) vector (λ), is proposed ad found to be excellently correlated to retention index of GC for alkanes. The MDE parameters were tested by the multiple linear regression (MLR) estimation and production of the retention index of GC, and the results obtained are satisfactory.

关键词： Molecular distance-edge vector (λ) alkanes chemometrics multiple linear regression (MLR) retention index gas chromatography

Determination of butyltin compounds in sediments by gas chromatography with flame photometric detector

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Journal of Environmental Sciences 1995年第2期7卷 218-223页

作者： Xu Fuzheng Zan Jun Jiang Guibin Han Hengbin(Research Center for Eco - Environrnental effciences, Chinese Academy of Sciences , Beijing 100085 , China) Chinese Academy of Sci Rsch Ctr for Eco-Envmlt Sci Beijing China China

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关键词： butyltin species sediments gas chromatography

Supercritical fluid extraction and gas chromatography analysis of arsenic species from solid matrices

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Chinese Chemical Letters 2016年第2期27卷 241-246页

作者： Zhi-Feng Wang Zhao-Jie Cui School of Environmental Science and Engineering Shandong University

A method in combination with derivatization-supercritical fluid extraction（SFE） and gas chromatography（GC） for the speciation and quantitative determination of dimethylarsinate（DMA）, monomethylarsonate（MMA） and inorganic arsenic in solid matrices was investigated. Thioglycolic acid methyl ester（TGM） and thioglycolic acid ethyl ester（TGE） were evaluated as derivatization reagents. The effects of pressure, temperature, flow rate of supercritical CO_2, extraction time, modifier and microemulsion on the efficiency of extraction were systematically investigated. The procedure was applied to the analysis of real soil and sediment samples. Results showed that TGE was more effective for arsenic speciation as a derivatization reagent. Modifying supercritical CO_2 with methanol can greatly improve the extraction efficiency. Further, the addition of microemulsion containing surfactant Triton X-100 can further enhance recoveries of arsenic species. The optimum extraction conditions were 100 ℃, 30 MPa, 10 min static and 25 min dynamic extraction with 5%（v/v） methanol, and surfactant modified supercritical CO_2. Detection limits in solid matrices were 0.15, 0.3 and 1.2 mg/kg for DMA, MMA and inorganic arsenic,respectively. The method was validated by the recovery data. The resulting method was fast, easy to perform and selective in the extraction and detection of various arsenic species in solid matrices.

关键词： Supercritical fluid extraction Arsenic species analysis Thioglycolic acid methyl ester(TGM) Thioglycolic acid ethyl ester(TGE) Derivatization gas chromatography

A modified simplex method for multifactor optimization of selectivity in gas chromatography

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Chinese Journal of Chemistry 1995年第2期13卷 169-174页

作者： WANG, QS ZHU, CS YAN, BW NANKAI UNIV NATL LAB ELEMENTOORGAN CHEMTIANJIN 300071PEOPLES R CHINA

A computer-assisted advanced simplex method is presented for the simultaneous optimization of multifactor (stationary phase loading, carrier gas dow rate and column temperature) for separation of ten compounds in gas chromatography. A three factors factorial design was used. The method was based on a special polynomial established from fifteen preliminary runs, using resolution as the selection criterion, with connection to a general simplex method. Excellent agreement is found between the predicted data and the experimental results, and most of experiments required in the general simplex method can be omitted.

关键词： gas chromatography STATIONARY PHASE CARRIER gas FLOW RATE COLUMN TEMPERATURE MULTIFACTOR OPTIMIZATION

Detection of Tocopherol in Oilseed Rape (Brassica napus L.) Using gas chromatography with Flame Ionization Detector

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Journal of Integrative Agriculture 2013年第5期12卷 803-814页

作者： Nazim Hussain Zahra Jabeen LI Yuan-long CHEN Ming-xun LI Zhi-lan GUO Wan-li Imran Haider Shamsi CHEN Xiao-yang JIANG Li-xi Key Laboratory of Crop Germplasm Resources of Zhejiang Province College of Agriculture and BiotechnologyZhejiang University

The variation among Chinese genotypes of Brassica napus L. for seed tocopherols content and their analysis using gas chromatography has not been comprehensively reported till to date. In the present study, the tocopherol contents of four Chinese genotypes of Brassica napus L., namely, Gaoyou 605, Zhejiang 619, Zheshuang 758, and Zheshuang 72, were evaluated using three modified sample preparation protocols （P1, P2, and P3） for tocopherol extraction. These methods were distinguished as follows. Protocol one （P1） included the evaporation of solvent after extraction without silylation. Protocol two （P2） followed the direct supernatant collection after overnight extraction without drying and silylation. Protocol three （P3） included trimethylsilylation with N,O-bis（trimethylsilyl） trifluoroacetamide. Genotypic comparison of tocopherol and its isoforms revealed that Gaoyou 605 was dominant over the other genotypes with （140.5＋ 10.5）, （316.2＋ 9.2）, and （559.1＋ 24.3） ~tg g-~ of seed meal ct-, 7-, and total （T-） tocopherol, respectively, and a 0.44＋0.04 ^- to 7-tocopherol ratio. The comparison of the sample preparation protocols, on the other hand, suggests that P3 is the most suitable method for the tocopherol extraction from Brassica oilseeds and for the analysis of tocopherols using gas chromatography flame ionization detector （GC-FID）. Trimethylsilylation is the key step differentiating P3 from P1 and P2. Variations detected in tocopherol contents among the Chinese rapeseed （B. napus） genotypes signify the need to quantify a wide range of rapeseed germplasm for seed tocopherol dynamics in short and crop improvement in long.

关键词： Brassica napus L. genotypic variation tocopherol analysis gas chromatography flame ionization detector

Liquid-liquid Microextraction Based on Solidification of Floating Organic Drops Coupled with gas chromatography for Analyzing Trace Benzene, Toluene and Xylene in Water Samples

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Chemical Research in Chinese Universities 2011年第6期27卷 939-943页

作者： ZHANG Mao-sheng HUANG Jia-rong ZHENG Xiang-hua XIE Qiong-fang Department of Chemistry and Environmental Science Zhangzhou Normal University Zhangzhou 363000 P. R. China Zhangzhou Entry-Exit Inspection and Quarantine Bureau Zhangzhou 363000 P. R. China Inspection and Quarantine Technical Center Xiamen Entry-Exit Inspection and Quarantine Bureau Xiamen 361012 P. R. China

A new liquid-liquid microextraction method based on the solidification of floating organic drops coupled with gas chromatography was developed for the determination of trace benzene, toluene and xylene（BTX） in water samples. In the microextraction procedure, a microdrop of n-decanol was delivered to the surface of the analytes’ solution, and stirred for a desired time. Following the absolute extraction, the sample vial was cooled in an ice bath for 10 min. The solidified n-decanol was then transferred into a plastic tube and melted naturally; and 1 μL of it was injected into gas chromatography for analysis. Factors relevant to the extraction efficiency were studied and optimized. The optimal experimental conditions were： 15 μL of n-decanol as extractive solvent, 30 mL of solution containing analytes, no salt, the stirring rate 400 r/min, the extraction temperature 30 °C, and the extraction time 30 min. Under those optimized conditions, the detection limit（LOD） of analytes was in a range of 0.05―0.10 ng/mL by the developed method. A good linearity（r0.99） in a calibration range of 0.01―100 μg/mL was obtained. The recoveries of the real samples at different spiked levels of BTX were in the range from 92.2% to 103.4%.

关键词： gas chromatography Liquid-liquid microextraction Solidified floating organic drop n-Decanol

Triptycene-derived heterocalixarene:A new type of macrocycle-based stationary phases for gas chromatography

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Chinese Chemical Letters 2021年第6期32卷 2043-2046页

作者： Yongrui He Xiaohong Yang Meiling Qi Chuanfeng Chen Key Laboratory of Cluster Science Ministry of Education of ChinaSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China CAS Key Laboratory of Molecular Recognition and Function Institute of ChemistryChinese Academy of SciencesBeijing 100190China

This work reports the investigation of a new triptycene-derived oxacalixarene(TDOC)as the stationary phase for gas chromatography(GC)with high-resolution performance for a wide range of analytes and *** TDOC scaffold is composed of triptycene and 1,8-naphthyridine moieties,inherently differing from the conventional calixarenes in structures and *** a result,the TDOC column exhibited outstanding column efficiency of 5679 plates/m by n-dodecane at 120℃.It showed advantageous performance for separations of the mixtures with various analytes and achieved high resolution of diverse isomers(skeletal,positional and cis-/trans-isomers)from apolar to polar ***,the TDOC column exhibited high thermal stability up to 310℃.To date,the TDOC-based materials have not been reported in *** work demonstrates the good potential of the triptycene-derived heterocalixarenes as a new class of stationary phases for chromatographic analyses.

关键词： Triptycene-derived oxacalixarene Stationary phase Separation performance gas chromatography Isomers

A novel ionic liquids grafted polysiloxane for capillary gas chromatography

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Chinese Chemical Letters 2009年第9期20卷 1111-1114页

作者： Qing Quan Wei Mei Ling Qi Ruo Nong Fu Department of Chemistry School of Science Beijing Institute of Technology of China Beijing 100081 China

A new ionic liquids grafted polysiloxane used as stationary phase for capillary gas chromatography （CGC） is described. The stationary phase of 1-vinyl-3-hexylimidazolium hexafluorophosphate anchored to polysiloxane （PMHS-[VHIm][PF6]） was synthe- sized, characterized and coated onto capillary columns by static coating. The results show that the present stationary phase exhibits a very good chromatographic resolution and selectivity for Grob test mixture and alcohols with baseline resolution and symmetry peaks. The present work suggests that novel stationary phase has a great potential for further development and application. 2009 Mei Ling Qi. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Ionic liquids Polysiloxane Stationary phase gas chromatography

Solid-phase Microextraction with Benzoxy-calix[6]arene Fiber Coupled to gas chromatography for the Analysis of Polycyclic Aromatic Hydrocarbons in Water

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Chemical Research in Chinese Universities 2011年第2期27卷 198-202页

作者： YE Chang-wen ZHANG Xue-na HUANG Jiang-yan LI Xiu-juan PAN Si-yi College of Food Science ＆ Technology Huazhong Agricultural University Wuhan 430070 P. R. China

Headspace solid-phase microextraction（HS-SPME） with sol-gel calix[6]arene-containing fiber followed by gas chromatography with a flame ionization detector was used to examine the composition and distribution of seven polycyclic aromatic hydrocarbons（PAHs） in water. The novel SPME fiber exhibited higher extraction efficiency to PAHs compared with poly（dimethylsiloxane） and other calixarene-containing fibers. Extraction/retention mechanism based on the interactions between calixarenes and PAHs was discussed. Owing to the good selectivity and high extraction capability of this calixarene fiber, low detection limits were obtained in a range of 0.34―6.50 ng/L and the relative standard deviation values were ≤12.3% for all of the analytes. The linear ranges of the proposed method were five orders of magnitude for the tested compounds, with linear correlation coefficients（r） greater than 0.998. The method was applied to the determination of polycyclic aromatic hydrocarbons in nine water sources in Wuhan City, China. Standard addition method was selected for the quantification and the recovery values were in a satisfactory range. Total PAHs concentrations in the nine surface water samples were found to vary between undetectable and 8.840 μg/L with two- and three-ring PAHs predominating.

关键词： Polycyclic aromatic hydrocarbon Solid-phase microextraction Calixarene gas chromatography Water

A β-cyclodextrin covalent organic framework used as a chiral stationary phase for chiral separation in gas chromatography

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Chinese Chemical Letters 2022年第2期33卷 898-902页

作者： Bo Tang Wei Wang Huipeng Hou Yiquan Liu Zongkun Liu Lina Geng Liquan Sun Aiqin Luo Key Laboratory of Molecular Medicine and Biotherapy School of Life ScienceBeijing Institute of TechnologyBeijing 100081China

Chiral covalent organic frameworks(CCOFs) featuring chirality, stability, and good porosity have attracted a considerable amount of attention due to their important applications, such as asymmetric catalysis, chiral separation, and chiral recognition. In this study, a β-cyclodextrin(β-CD) covalent organic framework(β-CD-COF) diluted with polysiloxane OV-1701 was explored as a novel chiral stationary phase(CSP) for gas chromatography(GC) separation of racemates. The β-CD-COF coated capillary column had excellent selectivity, not only for the separation of linear alkanes, linear alcohols, fatty acid methyl esters mixture, the Grob mixture and positional isomers, but also for the resolution of chiral compounds, including chiral alcohols, aldehydes, ethers, and amino acid derivatives. In addition, the β-CD-COF-coated capillary column presented good repeatability and reproducibility. This work indicated the great potential of the CCOFs coated capillary column for the chromatographic separation of enantiomers.

关键词： β-Cyclodextrin Covalent organic framework Chiral stationary phase gas chromatography Enantioseparation