Among various ionization detectors for gas chromatography(GC), the most promising one is perhaps the nonradioactive ionization detector which makes use of a microwave induced plasma(MIP). The use of MIP for gas chroma...Among various ionization detectors for gas chromatography(GC), the most promising one is perhaps the nonradioactive ionization detector which makes use of a microwave induced plasma(MIP). The use of MIP for gas chromatography was first studied by McCormack, et al. in 1965, Freeman developed a photoionization detector utilizing helium microwave discharge. In 1971, we developed a microwave展开更多
In this study, whole-oil gas chromatographic fingerprint analyses were performed on oils from the Es3^3 reservoir in the Liubei area of the Nanpu Sag. The gas chromatographic peaks of cyclic and branched alkanes with ...In this study, whole-oil gas chromatographic fingerprint analyses were performed on oils from the Es3^3 reservoir in the Liubei area of the Nanpu Sag. The gas chromatographic peaks of cyclic and branched alkanes with relatively high resolution from nCl0 to nC25 were selected to establish a database of whole-oil gas chromatographic peak height ratio fingerprints. Reservoir fluid connectivity was identified by using clustering analysis. This method can reflect the gas chromatography fingerprint information accurately and entirely, and avoid the one-sidedness of the star diagram method which only selects several fixed gas chromatographic peaks.展开更多
Heptakis(2.6-di-O-pentyl-3-O-ally)-β-cyclodextrin as an excellent gas chromatographic stationary phase separating phenol and cresol isomers is described.
A rapid method was developed for the determination of diazinon in plasma using gas chromatography with electron-capture detection (GC-ECD). Following a single extraction with hexane from 100μl of plasma, diazinon was...A rapid method was developed for the determination of diazinon in plasma using gas chromatography with electron-capture detection (GC-ECD). Following a single extraction with hexane from 100μl of plasma, diazinon was quantitated on a 3% OV-17 column. The detection limit was 10 ng/ml and linearity was obtained in the range of 25 ng/ml-2500 ng/ml.The applicability of the assay to single-dose kinetics in rats is illustrated展开更多
A rapid analytical method was first developed to detect organophosphorus pesticides(OPPs)in cereals,which used dynamic microwave assisted extraction(DMAE)coupled online with a modified quick,easy,cheap,effective,rugge...A rapid analytical method was first developed to detect organophosphorus pesticides(OPPs)in cereals,which used dynamic microwave assisted extraction(DMAE)coupled online with a modified quick,easy,cheap,effective,rugged,and safe(QuEChERS)method.Cereals samples were mixed with a certain amount of quartz,Ci8 and the primary second amine(PSA),and extracted successively with the acetonitrile-water solution(80%,VIV)under microwave irradiation.The obtained eluate was directly introduced into a collection tube containing NaCl and MgSO4.Finally,the supemate was evaporated and reconstructed,and determined by gas chromatographic spectrometry.Some factors affecting the experimental results were studied and optimized.The extraction and purification processes were carried out coinstantaneously and 12 samples could be treated in one step in 4 min.Low limits of tection(0.43—1.31 p.g/kg)for OPPs were obtained in cereals.The relative standard deviations(RSDs)were 2.1%—9.3%.The recoveries of OPPs ranged from 76.1%to 100.2%.By combining the advantages of DMAE with QuEChERS,the sample pretreatment process was simple to operate,with little amount of organic solvent.The whole extraction process was completed in a closed environment,therefore it was very appropriate for daily analysis of OPPs in cereals.展开更多
Eight fatty acids from beaver oil were identified by GC-9A, and their contents were determinded. A simple yet effective method for separation and quantification was described. Contents of the fatty acids were related ...Eight fatty acids from beaver oil were identified by GC-9A, and their contents were determinded. A simple yet effective method for separation and quantification was described. Contents of the fatty acids were related to their conditions of extraction.展开更多
Combining improved injector, gas line and valve-driving models, a gas chromatograph (GC) equipped with Hydrogen Flame Ionization Detector (FID) and Electron Capture Detector (ECD), can measure CH4, CO2, and N2O simult...Combining improved injector, gas line and valve-driving models, a gas chromatograph (GC) equipped with Hydrogen Flame Ionization Detector (FID) and Electron Capture Detector (ECD), can measure CH4, CO2, and N2O simultaneously in an air sample in four minutes. Test results show that the system has high sensitivity, resolution, and precision; the linear response range of the system meets the requirement of flux measurements in situ. The system is suitable for monitoring fluxes of the main greenhouse gases in a short-plant field since it is easy to use, efficacious, and constant and reliable in collecting data.展开更多
Rapid on-site identification of volatile organic compounds （VOCs） in ambient air is an important first step in remediation efforts. This study describes modification of a commercially available, portable GC/MS syste...Rapid on-site identification of volatile organic compounds （VOCs） in ambient air is an important first step in remediation efforts. This study describes modification of a commercially available, portable GC/MS system and development of an analysis protocol for rapid （〈 3 min） sampling and identification of VOCs typically found at contaminated sites at the low ppbv level.展开更多
Objective Many studies have been conducted in order to evaluate the genotoxicity of chemicals and waste materials, which utilized in vivo test protocols. The use of animals for routine toxicity testing is now question...Objective Many studies have been conducted in order to evaluate the genotoxicity of chemicals and waste materials, which utilized in vivo test protocols. The use of animals for routine toxicity testing is now questioned by a growing segment of society. Methods Keeping the above fact in mind, we have conducted in the present study the genotoxicity evaluation of oily sludge samples generated from a petroleum refinery and petrochemical industry and ETP sludge from petroleum refinery using DNA damage, chromosomal aberration, p53 protein induction and apoptosis in short term in vitro mammalian Chinese Hamster Ovary cell cultures. Results It is evident from the results that the oily sludge compounds derived from petroleum refinery and petrochemical industry could cause DNA damage, chromosomal aberration, p53 protein accumulation and apoptotic cell death on exposure to oily sludge extracts in the presence of metabolic activation system (S-9 mix), however, ETP sludge extract could not cause significant genotoxicity in comparison to oily sludge extract and negative control. Conclusion The effect may be attributed to polycyclic aromatic hydrocarbons present in the samples as evidenced from GC-MS.展开更多
A molecular electronegativity distance vector based on 13 atomic types (MEDV-13) is used to describe the structures of 62 polychlorinated naphthalene (PCN) congeners and related to the gas chromatographic relative ret...A molecular electronegativity distance vector based on 13 atomic types (MEDV-13) is used to describe the structures of 62 polychlorinated naphthalene (PCN) congeners and related to the gas chromatographic relative retention indices (RIs) of PCNs. Using multiple linear regression, a 4-variable quantitative structure-retention relationship (QSRR) with the correlation coefficient of estimations (r) being 0.9912 and the root mean square error of estimations (RMSEE) being 31.4 and the correlation coefficient of predictions (q) and the root mean square error of predictions (RMSEP) in the leave-one-out procedure are 0.9898 and 33.76, respectively.展开更多
[ Objective ] To prepare standard work solution of three pesticides used in the intermediate check of gas chromatograph and evaluate the uncertainty of solution. [ Method ] In view of intermediate check needs of gas c...[ Objective ] To prepare standard work solution of three pesticides used in the intermediate check of gas chromatograph and evaluate the uncertainty of solution. [ Method ] In view of intermediate check needs of gas chromatograph, common pesticides in pesticide residual test were taken as the study objects, i.e., hexachlorabenzene, malathion and Sulfotep, state pesticide reference materials as the materials, volumetry was applied to prepare standard work solution of pesti- cides. Evenness and stability of the work solution was tested by using gas chromatographs installed with electron capture detector （ECD）, flame photometric detec- tor （FPD） and flame ionization detector （ FID）, respectively, and after the evaluation of concentration, uncertainty of the work solution was assessed from the per- spectives of raw materials, preparation process, evenness and stability. [ Result ] Mass concentrations of the three standard work solution was 0.1 mg/L, 10.0mg/ L, 100.0 mg/L, respectively, and relative expanded uncertainty 2.640%, 1. 980% and 2.400% （ k = 2）. [ Conclusion] The study offers technical support for the intermediate check of laboratory apparatuses.展开更多
Volatile components in the extracts of basil leaves (Ocimum basilicum L.) were identified by gas chromatography/mass spectrometry (GC/MS) with electron ionization (EI) mode. The major volatile components of basil unde...Volatile components in the extracts of basil leaves (Ocimum basilicum L.) were identified by gas chromatography/mass spectrometry (GC/MS) with electron ionization (EI) mode. The major volatile components of basil under investigation are α-pinene, sabinene, β-pinene, d-limonene, eucalyptol, l-linalool and estragole. Electron ionization mass spectra of these compounds have been obtained and investigated. Furthermore, the semi-empirical MNDO [Modified Neglect of Diatomic Overlap] method was used to calculate the thermochemical data for the structural properties of these compounds.展开更多
The emission of N2 is important to remove excess N from lakes, ponds, and wetlands. To investigate the gas emission from water, Gao et al.（2013） developed a new method using a bubble trap device to collect gas sampl...The emission of N2 is important to remove excess N from lakes, ponds, and wetlands. To investigate the gas emission from water, Gao et al.（2013） developed a new method using a bubble trap device to collect gas samples from waters. However, the determination accuracy of sampling volume and gas component concentration was still debatable. In this study, the method was optimized for in situ sampling, accurate volume measurement and direct injection to a gas chromatograph for the analysis of N2 and other gases. By the optimized new method, the recovery rate for N2 was 100.28% on average; the mean coefficient of determination（R2） was 0.9997; the limit of detection was 0.02%. We further assessed the effects of the new method, bottle full of water, vs. vacuum bag and vacuum vial methods, on variations of N2 concentration as influenced by sample storage times of 1,2, 3, 5, and 7 days at constant temperature of 15°C, using indices of averaged relative peak area（%） in comparison with the averaged relative peak area of each method at 0 day.The indices of the bottle full of water method were the lowest（99.5%–108.5%） compared to the indices of vacuum bag and vacuum vial methods（119%–217%）. Meanwhile, the gas chromatograph determination of other gas components（O2, CH4, and N2O） was also accurate. The new method was an alternative way to investigate N2 released from various kinds of aquatic ecosystems.展开更多
文摘Among various ionization detectors for gas chromatography(GC), the most promising one is perhaps the nonradioactive ionization detector which makes use of a microwave induced plasma(MIP). The use of MIP for gas chromatography was first studied by McCormack, et al. in 1965, Freeman developed a photoionization detector utilizing helium microwave discharge. In 1971, we developed a microwave
基金funded by Shandong Provincial Key Laboratory of Depositional Mineralization & Sedimentary Minerals (Project DMSM201009)Key Laboratory of Tectonics and Petroleum Resources (China University of Geosciences), Ministry of Education, China (Project TPR-2010-29)
文摘In this study, whole-oil gas chromatographic fingerprint analyses were performed on oils from the Es3^3 reservoir in the Liubei area of the Nanpu Sag. The gas chromatographic peaks of cyclic and branched alkanes with relatively high resolution from nCl0 to nC25 were selected to establish a database of whole-oil gas chromatographic peak height ratio fingerprints. Reservoir fluid connectivity was identified by using clustering analysis. This method can reflect the gas chromatography fingerprint information accurately and entirely, and avoid the one-sidedness of the star diagram method which only selects several fixed gas chromatographic peaks.
文摘Heptakis(2.6-di-O-pentyl-3-O-ally)-β-cyclodextrin as an excellent gas chromatographic stationary phase separating phenol and cresol isomers is described.
文摘A rapid method was developed for the determination of diazinon in plasma using gas chromatography with electron-capture detection (GC-ECD). Following a single extraction with hexane from 100μl of plasma, diazinon was quantitated on a 3% OV-17 column. The detection limit was 10 ng/ml and linearity was obtained in the range of 25 ng/ml-2500 ng/ml.The applicability of the assay to single-dose kinetics in rats is illustrated
基金Supported by the National Key R&D Program of China(No.2018 YFD040013).
文摘A rapid analytical method was first developed to detect organophosphorus pesticides(OPPs)in cereals,which used dynamic microwave assisted extraction(DMAE)coupled online with a modified quick,easy,cheap,effective,rugged,and safe(QuEChERS)method.Cereals samples were mixed with a certain amount of quartz,Ci8 and the primary second amine(PSA),and extracted successively with the acetonitrile-water solution(80%,VIV)under microwave irradiation.The obtained eluate was directly introduced into a collection tube containing NaCl and MgSO4.Finally,the supemate was evaporated and reconstructed,and determined by gas chromatographic spectrometry.Some factors affecting the experimental results were studied and optimized.The extraction and purification processes were carried out coinstantaneously and 12 samples could be treated in one step in 4 min.Low limits of tection(0.43—1.31 p.g/kg)for OPPs were obtained in cereals.The relative standard deviations(RSDs)were 2.1%—9.3%.The recoveries of OPPs ranged from 76.1%to 100.2%.By combining the advantages of DMAE with QuEChERS,the sample pretreatment process was simple to operate,with little amount of organic solvent.The whole extraction process was completed in a closed environment,therefore it was very appropriate for daily analysis of OPPs in cereals.
文摘Eight fatty acids from beaver oil were identified by GC-9A, and their contents were determinded. A simple yet effective method for separation and quantification was described. Contents of the fatty acids were related to their conditions of extraction.
文摘Combining improved injector, gas line and valve-driving models, a gas chromatograph (GC) equipped with Hydrogen Flame Ionization Detector (FID) and Electron Capture Detector (ECD), can measure CH4, CO2, and N2O simultaneously in an air sample in four minutes. Test results show that the system has high sensitivity, resolution, and precision; the linear response range of the system meets the requirement of flux measurements in situ. The system is suitable for monitoring fluxes of the main greenhouse gases in a short-plant field since it is easy to use, efficacious, and constant and reliable in collecting data.
基金supported by a grant from the Syracuse Center of Excellence
文摘Rapid on-site identification of volatile organic compounds （VOCs） in ambient air is an important first step in remediation efforts. This study describes modification of a commercially available, portable GC/MS system and development of an analysis protocol for rapid （〈 3 min） sampling and identification of VOCs typically found at contaminated sites at the low ppbv level.
文摘Objective Many studies have been conducted in order to evaluate the genotoxicity of chemicals and waste materials, which utilized in vivo test protocols. The use of animals for routine toxicity testing is now questioned by a growing segment of society. Methods Keeping the above fact in mind, we have conducted in the present study the genotoxicity evaluation of oily sludge samples generated from a petroleum refinery and petrochemical industry and ETP sludge from petroleum refinery using DNA damage, chromosomal aberration, p53 protein induction and apoptosis in short term in vitro mammalian Chinese Hamster Ovary cell cultures. Results It is evident from the results that the oily sludge compounds derived from petroleum refinery and petrochemical industry could cause DNA damage, chromosomal aberration, p53 protein accumulation and apoptotic cell death on exposure to oily sludge extracts in the presence of metabolic activation system (S-9 mix), however, ETP sludge extract could not cause significant genotoxicity in comparison to oily sludge extract and negative control. Conclusion The effect may be attributed to polycyclic aromatic hydrocarbons present in the samples as evidenced from GC-MS.
基金We are especially grateful to the China Postdoctoral Science Foundation and the National High Technology Project of China (No. 2001AA640601) for their financial supports.
文摘A molecular electronegativity distance vector based on 13 atomic types (MEDV-13) is used to describe the structures of 62 polychlorinated naphthalene (PCN) congeners and related to the gas chromatographic relative retention indices (RIs) of PCNs. Using multiple linear regression, a 4-variable quantitative structure-retention relationship (QSRR) with the correlation coefficient of estimations (r) being 0.9912 and the root mean square error of estimations (RMSEE) being 31.4 and the correlation coefficient of predictions (q) and the root mean square error of predictions (RMSEP) in the leave-one-out procedure are 0.9898 and 33.76, respectively.
基金Sponsored by National Scientific and Technological Support Program(2012BAK25B03-12)
文摘[ Objective ] To prepare standard work solution of three pesticides used in the intermediate check of gas chromatograph and evaluate the uncertainty of solution. [ Method ] In view of intermediate check needs of gas chromatograph, common pesticides in pesticide residual test were taken as the study objects, i.e., hexachlorabenzene, malathion and Sulfotep, state pesticide reference materials as the materials, volumetry was applied to prepare standard work solution of pesti- cides. Evenness and stability of the work solution was tested by using gas chromatographs installed with electron capture detector （ECD）, flame photometric detec- tor （FPD） and flame ionization detector （ FID）, respectively, and after the evaluation of concentration, uncertainty of the work solution was assessed from the per- spectives of raw materials, preparation process, evenness and stability. [ Result ] Mass concentrations of the three standard work solution was 0.1 mg/L, 10.0mg/ L, 100.0 mg/L, respectively, and relative expanded uncertainty 2.640%, 1. 980% and 2.400% （ k = 2）. [ Conclusion] The study offers technical support for the intermediate check of laboratory apparatuses.
文摘Volatile components in the extracts of basil leaves (Ocimum basilicum L.) were identified by gas chromatography/mass spectrometry (GC/MS) with electron ionization (EI) mode. The major volatile components of basil under investigation are α-pinene, sabinene, β-pinene, d-limonene, eucalyptol, l-linalool and estragole. Electron ionization mass spectra of these compounds have been obtained and investigated. Furthermore, the semi-empirical MNDO [Modified Neglect of Diatomic Overlap] method was used to calculate the thermochemical data for the structural properties of these compounds.
基金supported by the National Natural Science Foundation of China (No.41301575)Special Preliminary Study Program of the National Basic Research Program (973) of China (No. 2012CB426503)
文摘The emission of N2 is important to remove excess N from lakes, ponds, and wetlands. To investigate the gas emission from water, Gao et al.（2013） developed a new method using a bubble trap device to collect gas samples from waters. However, the determination accuracy of sampling volume and gas component concentration was still debatable. In this study, the method was optimized for in situ sampling, accurate volume measurement and direct injection to a gas chromatograph for the analysis of N2 and other gases. By the optimized new method, the recovery rate for N2 was 100.28% on average; the mean coefficient of determination（R2） was 0.9997; the limit of detection was 0.02%. We further assessed the effects of the new method, bottle full of water, vs. vacuum bag and vacuum vial methods, on variations of N2 concentration as influenced by sample storage times of 1,2, 3, 5, and 7 days at constant temperature of 15°C, using indices of averaged relative peak area（%） in comparison with the averaged relative peak area of each method at 0 day.The indices of the bottle full of water method were the lowest（99.5%–108.5%） compared to the indices of vacuum bag and vacuum vial methods（119%–217%）. Meanwhile, the gas chromatograph determination of other gas components（O2, CH4, and N2O） was also accurate. The new method was an alternative way to investigate N2 released from various kinds of aquatic ecosystems.
