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Determination of 14 Organophosphorus Pesticide Residues in Mutton by Gel Permeation Chromatography-Gas Chromatography-Mass Spectrometry(GPC-GC-MS)
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作者 Junpeng ZHAO Richard Avoi +2 位作者 Azman Bin Atil@Azmi Jiao CHEN Ling YUN 《Agricultural Biotechnology》 2024年第3期28-30,33,共4页
[Objectives]This study was conducted to purify mutton samples by gel permeation chromatography(GPC).[Methods]Fourteen organophosphorus pesticide residues in samples were qualitatively and quantitatively analyzed by ga... [Objectives]This study was conducted to purify mutton samples by gel permeation chromatography(GPC).[Methods]Fourteen organophosphorus pesticide residues in samples were qualitatively and quantitatively analyzed by gas chromatography-mass spectrometry(GC-MS)in selective ion scanning mode(SIM).[Results]The organophosphorus pesticide standard solutions showed good linearity in the mass concentration range of 0.1-10.0μg/ml with correlation coefficients(r)not lower than 0.999,and the detection limits(S=3 N)ranged from 0.01 to 0.05 mg/kg.The average recovery values were in the range of 80.2%-99.7%,with relative standard deviations(RSDs,n=3)in the range of 1.8%-6.3%,at the addition levels of 0.5,1.0 and 2.0 mg/kg.[Conclusions]The method is simple,sensitive and accurate,and can be used for the determination of organophosphorus pesticide residues in mutton. 展开更多
关键词 MUTTON gas chromatography-mass spectrometry Gel permeation chromatography ORGANOPHOSPHORUS Pesticide residue
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Determination of 8 Diuretics and Probenecid in Human Urine by Gas Chromatography-Mass Spectrometry: Confirmation Procedure 被引量:2
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作者 Olga Zaporozhets Iuna Tsyrulneva Mykola Ischenko 《American Journal of Analytical Chemistry》 2012年第4期320-327,共8页
A fast and sensitive method for determination of 8 diuretics (acetazolamide, bendroflumethiazide, bumetanide, chlorthalidone, furosemide, hydrochlorothiazide, metolazone, triamterene) and masking agent (probenecid) in... A fast and sensitive method for determination of 8 diuretics (acetazolamide, bendroflumethiazide, bumetanide, chlorthalidone, furosemide, hydrochlorothiazide, metolazone, triamterene) and masking agent (probenecid) in human urine using gas-chromatography with mass spectrometric detection is described. The extraction of the substances as function of the nature of organic solvent, mixing time and pH of aqueous phase was studied. The tandem mass spectrometry was used to increase selectivity of diuretics determination due to elimination of background interferences. Fragmentation reactions were studied for each compound and their collision energies were optimized to obtain the best selectivity. The results of method’s validation demonstrate its suitability in routine analysis for confirmation purposes. 展开更多
关键词 DIURETICS URINE gas chromatography TANDEM Mass spectrometry CONFIRMATION
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Gel Permeation Chromatography Purification and Gas Chromatography-Mass Spectrometry Detection of Multi-Pesticide Residues in Traditional Chinese Medicine 被引量:2
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作者 Wan-E Zhuang Zhen-Bin Gong 《American Journal of Analytical Chemistry》 2012年第1期24-32,共9页
The measurement of 23 organochlorine, organophosphorus, and pyrethroid pesticides in typical traditional Chinese medicine (TCM), flos lonicerae, was made using gel permeation chromatography (GPC) purification and gas ... The measurement of 23 organochlorine, organophosphorus, and pyrethroid pesticides in typical traditional Chinese medicine (TCM), flos lonicerae, was made using gel permeation chromatography (GPC) purification and gas chroma- tography-mass spectrometry (GC-MS) detection. The pesticides were extracted with ultrasonic device and 5.0 mL mixture of ethyl acetate and cyclohexane (1:1, v/v). Coextractants from sample matrices which may have interfere to the qualitative and quantitative analysis, such as pigments, were removed using GPC purification. Simultaneous full scan and selective ion monitor (scan/SIM) mode for GC-MS was used for qualitative and quantitative analysis, which pro- vided retention time and characteristic fragments ratio for each pesticide so as to positively identify each analyte. Rela- tive standard deviations (RSDs) were within 7.7% (5.0 - 22.5 μg/kg, n = 3). The recoveries of pesticide standards at the spiked concentration of 5.0 - 22.5 μg/kg were between 87.1% and 110.9%. Limits of detection (LODs) for the analytes were 0.16 - 3.2 μg/kg, which could meet the demand of routine analysis and TCM quality control. 展开更多
关键词 Traditional Chinese Medicine Multi-Pesticide RESIDUE Flos Lonicerae Gel PERMEATION chromatography gas chromatography-mass spectrometry
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Structure Elucidation of a New Toxin from the Mushroom Cortinarius rubellus Using Gas Chromatography-Mass Spectrometry (GC-MS)
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作者 Ilia Brondz 《International Journal of Analytical Mass Spectrometry and Chromatography》 2013年第2期109-118,共10页
Cortinarius orellanus (Fries) and C. rubellus (Cooke),which were formerly also known as C. speciosissimus, are poisonous mushrooms containing the toxin orellanine and several degradation products of orellanine,includi... Cortinarius orellanus (Fries) and C. rubellus (Cooke),which were formerly also known as C. speciosissimus, are poisonous mushrooms containing the toxin orellanine and several degradation products of orellanine,includingorelline and orellinine. Mass intoxication by poisonous mushrooms was observed in Poland in 1952-1957 [1]. In 1957, the cause of these outbreaks was described by Grzymala as poisoning by a member of the Cortinarius family. The toxin orellanine was first isolated from C. orellanusby Grzymala in 1962;the chemical structure of orellanine was later determined to be 3,3',4,4'-tetrahydroxy-2,2'-bipyridine-N,N'-dioxide. Poisoning with C. orellanus and C. rubellus has a very specific character. The first symptoms of intoxication usually do not appear until 2-3 days after ingestion, but in some cases intoxication appears after three weeks. The target organ for the toxin is the kidney. Histologically, it is easy to record the specific damage. The presence of degradation products of orellanine in kidney can be confirmed chromatographically, suggesting that the cause of poisoning is orellanine. However, the presence of orellanine in the blood of intoxicated persons has not been directly detected. A specific model was developed by Brondz et al. for the detection of orellanine, orelline, and orellininein animal stomach fluids [2-4]. The hypothesis that the fungal toxin orellanine as a diglucoside can be transported from the digestive system by the blood to the kidney could not be supported. The toxin orellanine as a diglucoside is very unstable in an aqueous acidic environment.[i1]?However, in the present study, it was possible to record an additional substance in animal stomach fluids using GC-MSafter ingestion ofC. rubellus. This substance, which has been namedrubelline, is part of a toxic mixture inC. orellanusandC. rubellusand is closely related to orellanine. The structure of rubelline is more suitable than orellanine for absorptionfromthe digestive tract and for transport in the blood. The presented hypothesis is that rubellineis absorbed in the digestive tract and transportedin the blood to the kidney, where it is biotransformed to orellanine and accumulatedto toxic levels. The process of biotransformationis in itself also damaging for the kidney and liver.[i2]?GC-MS instrumentation enables the separation of substances in biological samples and in the extract fromC. rubellus. The GC-MS with SMB technique was used to record the mass ion and to record a detailed fragmentation picture. 展开更多
关键词 gas chromatography Mass spectrometry
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Metabolomics of gastric cancer metastasis detected by gas chromatography and mass spectrometry 被引量:12
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作者 Jin-Lian Chen,Jun-Duo Hu,Jing Fan,Jing Hong,Department of Gastroenterology,Shanghai Sixth People’s Hospital,Shanghai Jiao Tong University,Shanghai 200233,China Hui-Qing Tang,Jian-Zhong Gu,Shanghai Laboratory Animal Center,Chinese Academy of Sciences,Shanghai 201615,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第46期5874-5880,共7页
AIM:To elucidate the underlying mechanisms of metastasis and to identify the metabolomic markers of gastric cancer metastasis.METHODS:Gastric tumors from metastatic and nonmetastatic groups were used in this study.Met... AIM:To elucidate the underlying mechanisms of metastasis and to identify the metabolomic markers of gastric cancer metastasis.METHODS:Gastric tumors from metastatic and nonmetastatic groups were used in this study.Metabolites and different metabolic patterns were analyzed by gas chromatography,mass spectrometry and principal components analysis (PCA),respectively.Differentiation performance was validated by the area under the curve (AUC) of receiver operating characteristic curves.RESULTS:Twenty-nine metabolites were differentially expressed in animal models of human gastric cancer.Of the 29 metabolites,20 were up-regulated and 9 were down-regulated in metastasis group compared to non-metastasis group.PCA models from the metabolite profiles could differentiate the metastatic from the nonmetastatic specimens with an AUC value of 1.0.These metabolites were mainly involved in several metabolic pathways,including glycolysis (lactic acid,alaline),serine metabolism (serine,phosphoserine),proline metabolism (proline),glutamic acid metabolism,tricarboxylic acid cycle (succinate,malic acid),nucleotide metabolism (pyrimidine),fatty acid metabolism (docosanoic acid,and octadecanoic acid),and methylation(glycine).The serine and proline metabolisms were highlighted during the progression of metastasis.CONCLUSION:Proline and serine metabolisms play an important role in metastasis.The metabolic profiling of tumor tissue can provide new biomarkers for the treatment of gastric cancer metastasis. 展开更多
关键词 gasTRIC cancer METASTASIS METABOLITE Metabolomics gas chromatography and mass spectrometry
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Gas chromatography/mass spectrometry based metabolomic study in a murine model of irritable bowel syndrome 被引量:7
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作者 Lei-Min Yu Ke-Jia Zhao +2 位作者 Shuang-Shuang Wang Xi Wang Bin Lu 《World Journal of Gastroenterology》 SCIE CAS 2018年第8期894-904,共11页
AIM To study the role of microbial metabolites in the modulation of biochemical and physiological processes in irritable bowel syndrome(IBS).METHODS In the current study, using a metabolomic approach, we analyzed the ... AIM To study the role of microbial metabolites in the modulation of biochemical and physiological processes in irritable bowel syndrome(IBS).METHODS In the current study, using a metabolomic approach, we analyzed the key metabolites differentially excreted in the feces of control mice and mice with IBS, with or without Clostridium butyricum(C. butyricum) treatment. C57 BL/6 mice were divided into control, IBS, and IBS + C. butyricum groups. In the IBS and IBS + C. butyricum groups, the mice were subjected to water avoidance stress(WAS) for 1 h/d for ten days. Gas chromatography/mass spectrometry(GC-MS) together with multivariate analysis was employed to compare the fecal samples between groups. RESULTS WAS exposure established an appropriate model of IBS in mice, with symptoms of visceral hyperalgesia and diarrhea. The differences in the metabolite profiles between the control group and IBS group significantly changed with the progression of IBS(days 0, 5, 10, and 17). A total of 14 differentially excreted metabolites were identified between the control and IBS groups, and phenylethylamine was a major metabolite induced by stress. In addition, phenylalanine metabolism was found to be the most relevant metabolic pathway. Between the IBS group and IBS + C. butyricum group, 10 differentially excreted metabolites were identified. Among these, pantothenate and coenzyme A(Co A) biosynthesis metabolites, as well as steroid hormone biosynthesis metabolites were identified as significantly relevant metabolic pathways.CONCLUSION The metabolic profile of IBS mice is significantly altered compared to control mice. Supplementation with C. butyricum to IBS mice may provide a considerable benefit by modulating host metabolism. 展开更多
关键词 IRRITABLE BOWEL syndrome METABOLITE gas chromatography/mass spectrometry CLOSTRIDIUM butyricum
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Analyzing crude oils from the Junggar Basin(NW China) using comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry(GC×GC-TOFMS) 被引量:1
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作者 Yuce Wang Wanyun Ma +2 位作者 Ni Zhou Jiangling Ren Jian Cao 《Acta Geochimica》 EI CAS CSCD 2017年第1期66-73,共8页
As a new technology of analyzing crude oils,comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry(GC×GCTOFMS) has received much research attention.Here we present a case s... As a new technology of analyzing crude oils,comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry(GC×GCTOFMS) has received much research attention.Here we present a case study in the Junggar Basin of NW China.Results show that the hydrocarbons,including saturates and aromatics,were all well-separated without large coelution,which cannot be realized by conventional one-dimensional GC-MS.The GC×GC technique is especially effective for analyzing aromatics and low-to-middlemolecular-weight hydrocarbons,such as diamondoids.The geochemical characteristics of crude oils in the study area were investigated through geochemical parameters extracted by GC×GC-TOFMS,improving upon the understanding obtained by GC-MS.Thus,the work here represents a new successful application of GC×GCTOFMS,showing its broad usefulness in petroleum geochemistry. 展开更多
关键词 Comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry(GC×GC-TOFMS) Petroleum geochemistry Biomarkers Diamondoid Junggar Basin
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Headspace Solid-Phase Micro-Extraction Gas Chromatography/Mass Spectrometry(HS-SPME-GC/MS)-Based Untargeted Metabolomics Analysis for Comparing the Volatile Components from 12 Panax Herbal Medicines 被引量:1
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作者 Simiao Wang Xiaohang Li +8 位作者 Meiting Jiang Xinlong Wu Yuying Zhao Meiyu Liu Xiaoyan Xu Huimin Wang Hongda Wang Heshui Yu Wenzhi Yang 《Phyton-International Journal of Experimental Botany》 SCIE 2022年第7期1353-1364,共12页
Quality control of ginseng currently is mainly based on ginsenoside analysis,but rarely focuses on the volatile organic components.In the current work,an untargeted metabolomics approach,by headspace solid-phase micro... Quality control of ginseng currently is mainly based on ginsenoside analysis,but rarely focuses on the volatile organic components.In the current work,an untargeted metabolomics approach,by headspace solid-phase micro-extraction gas chromatography/mass spectrometry(HS-SPME-GC/MS),was elaborated and further employed to holistically compare the compositional difference of the volatile components simultaneously from 12 Panax herbal medicines,which included P.ginseng(PG),P.quinquefolius(PQ),P.notoginseng(PN),red ginseng(PGR),P.ginseng leaf(PGL),P.quinquefolius leaf(PQL),P.notoginseng leaf(PNL),P.ginseng flower(PGF),P.quinquefolius flower(PQF),P.notoginseng flower(PNF),P.japonicus(PJ),and P.japonicus var.major(PJvm).Chromatographic separation was performed on an HP-5MS elastic quartz capillary column using helium as the carrier gas,enabling good resolution within 1 h.We were able to characterize totally 259 volatile compounds,including 82 terpenes(T),46 alcohols(Alc),29 ketones(K),25 aldehydes(Ald),21 esters(E),and the others.By analyzing 90 batches of ginseng samples based on the untargeted metabolomics workflows,236 differential ions were unveiled,and accordingly 36 differential volatile components were discovered.It is the first report that simultaneously compares the compositional difference of volatile components among 12 Panax herbal medicines,and useful information is provided for the quality control of ginseng aside from the well-known ginsenosides. 展开更多
关键词 Headspace solid-phase micro-extraction gas chromatography/mass spectrometry PANAX volatile component untargeted metabolomics
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Occurrence of <i>N</i>-Acyl Homoserine Lactones in Extracts of Bacterial Strain of <i>Pseudomonas aeruginosa</i>and in Sputum Sample Evaluated by Gas Chromatography–Mass Spectrometry 被引量:1
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作者 Susheela Rani Ashwini Kumar +1 位作者 Ashok Kumar Malik P. Schmitt-Kopplin 《American Journal of Analytical Chemistry》 2011年第2期294-302,共9页
This study presents a fast, accurate and sensitive technique using gas chromatography-mass spectrometry (GC-MS) for the identification and quantification of N-acyl homoserine lactones (AHLs) in the extracts of bacteri... This study presents a fast, accurate and sensitive technique using gas chromatography-mass spectrometry (GC-MS) for the identification and quantification of N-acyl homoserine lactones (AHLs) in the extracts of bacterial strain of Pseudomonas aeruginosa and sputum sample of a cystic fibrosis patient. This method involves direct separation and determination of AHLs by using GC-MS as simultaneous separation and characterization of AHLs were possible without any prior derivatiza-tion. Electron ionization resulted in a common fragmentation pattern with the most common fragment ion at m/z 143 and other minor peaks at 73, 57 and 43. The limit of detection for N-butanoyl, N-hexanoyl, N-octanoyl, N-decanoyl, N-dodecanoyl and N-tetradecanoyl homoserine lactones was 2.14, 3.59, 2.71, 2.10, 2.45 and 2.34 μg/L, respectively. The presence of AHLs in the culture of P. aeruginosa strain and spu-tum of a cystic fibrosis patient was achieved in selected ion monitoring (SIM) mode by using the prominent fragment at m/z 143. 展开更多
关键词 gas chromatography—Mass spectrometry N-Acyl HOMOSERINE LACTONE (N-Butanoyl N-Hexanoyl N-Octanoyl N-Decanoyl N-Dodecanoyl and N-Tetradecanoyl) HOMOSERINE LACTONE SPUTUM Sample Bacterial Strain
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ANALYSIS OF VOLATILE CONSTITUENTS OF CHINESE MEDICINAL HERBS BY FLASH DISTILLATION/CAPILLARY GAS CHROMATOGRAPHY/MASS SPECTROMETRY
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《Chemical Research in Chinese Universities》 SCIE CAS 1986年第1期13-18,共6页
In present work,the volatile constituents of Curcuma longa L.,A.lancea (Thunb.) DC.,Foeniculum vulgare Mill,and Cinnamomun cassia Presl.have been analyzed by flash distillation/capillary gas chro-matography/mass spect... In present work,the volatile constituents of Curcuma longa L.,A.lancea (Thunb.) DC.,Foeniculum vulgare Mill,and Cinnamomun cassia Presl.have been analyzed by flash distillation/capillary gas chro-matography/mass spectrometry.The results are consistent with those obtained by conventional steam distillation extraction method.The optimum condition of flash distillation has been studied.The experimental results showed that this new technique proved to be a simple,rapid and efficient tool for microanalysis of volatile constituents of Chinese medicinal herbs. 展开更多
关键词 OC ANALYSIS OF VOLATILE CONSTITUENTS OF CHINESE MEDICINAL HERBS BY FLASH DISTILLATION/CAPILLARY gas chromatography/MASS spectrometry gas
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The Detection of THCA Using 2-Dimensional Gas Chromatography-Tandem Mass Spectrometry in Human Fingernail Clippings: Method Validation and Comparison with Head Hair
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作者 Joseph Jones Mary Jones +1 位作者 Charles Plate Douglas Lewis 《American Journal of Analytical Chemistry》 2013年第10期1-8,共8页
Marijuana use as well as abuse is a significant public health and public safety concern in the United States and using hair to identify marijuana users and abusers has been gaining acceptance in a number of venues inc... Marijuana use as well as abuse is a significant public health and public safety concern in the United States and using hair to identify marijuana users and abusers has been gaining acceptance in a number of venues including workplace, court ordered, and substance abuse treatment monitoring. After the presentation of a fully validated 2-dimensional gas chromatography-tandem mass spectrometry method for the detection of 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THCA), the chief metabolite of the main psychoactive compound in marijuana, Δ9-tetrahydrocannabinol (THC), we evaluated the usefulness of fingernail clippings as an alternative specimen type to hair by the analysis of a set of 60 matched pairs of head hair and fingernail clippings. The limit of detection was 10 fg/mg, the limit of quantitation was 20 fg/mg, and the assay was linear from 20 fg/mg to 500 fg/mg. The intra- and inter-assay imprecision and bias studies at 4 different concentrations (50, 100, 500, and 1000 fg/mg) were acceptable where all % Target observations were within 16% of their expected concentrations and all %CV calculations were less than 13.5%. THCA was detectable in more fingernail specimens (53.3%) than hair specimens (46.7%) and the mean concentrations in nails were on average 4.9 times higher than in hair (1813 fg/mg and 364 fg/mg, respectively). The THCA concentrations in hair and nail were strongly associated (r = 0.974, P < 0.01, n = 60) and the association was significant. The study demonstrated that fingernail clippings are a suitable alternative specimen type to hair to monitor for marijuana use and abuse. 展开更多
关键词 11-Nor-9-Carboxy-Δ9-Tetrahydrocannabinol THCA Carboxy-THC HAIR Fingernail 2D-GC-MS/MS 2-Dimensional gas chromatography Tandem Mass spectrometry
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Analysis of residual crosslinking agent content in UV cross-linked poly(ethylene oxide) hydrogels for dermatological application by gas chromatography 被引量:1
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作者 Rachel Shet Hui Wong Mark Ashton Kalliopi Dodou 《Journal of Pharmaceutical Analysis》 SCIE CAS 2016年第5期307-312,共6页
Acrylates have been widely used in the synthesis of pharmaceutical polymers. The quantitation of residual acrylate monomers is vital as they are strong irritants and allergens, but after polymerization, are relatively... Acrylates have been widely used in the synthesis of pharmaceutical polymers. The quantitation of residual acrylate monomers is vital as they are strong irritants and allergens, but after polymerization, are relatively inert, causing no irritation and allergies. Poly(ethylene oxide)(PEO) hydrogels were prepared using pentaerythritol tetra-acrylate(PETRA) as UV crosslinking agent. A simple, accurate, and robust quantitation method was developed based on gas chromatographic techniques(GC), which is suitable for routine analysis of residual PETRA monomers in these hydrogels. Unreacted PETRA was initially identified using gas chromatography–mass spectrometry(GC–MS). The quantitation of analyte was performed and validated using gas chromatography equipped with a flame ionization detector(GC–FID). A linear relationship was obtained over the range of 0.0002%–0.0450%(m/m) with a correlation coefficient(r2)greater than 0.99. The recovery( 4 90%), intra-day precision(%RSD o 0.67), inter-day precision(%RSD o2.5%), and robustness(%RSD o1.62%) of the method were within the acceptable values. The limit of detection(LOD) and limit of quantitation(LOQ) were 0.0001%(m/m) and 0.0002%(m/m), respectively.This assay provides a simple and quick way of screening for residual acrylate monomer in hydrogels. 展开更多
关键词 Poly(ethylene oxide) (PEO) RESIDUAL MONOMER Hydrogelgas chromatography–mass spectrometry (GC–MS) gas chromatography–flame ionization detection (GC–FID)
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Coupling a Gas Chromatography Unit to an Inductively Coupled Plasma Mass Spectrometer
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作者 Jerrad P. Auxier John D. Auxier II Howard L. Hall 《World Journal of Nuclear Science and Technology》 2017年第2期84-92,共9页
Although the eminent threat of a terrorist group detonating an improvised nuclear device (IND) in an urban environment is low, it is crucial that countries develop modern nuclear forensic capabilities to expedite resp... Although the eminent threat of a terrorist group detonating an improvised nuclear device (IND) in an urban environment is low, it is crucial that countries develop modern nuclear forensic capabilities to expedite response in a post-detonation scenario. In particular, new instruments need to be created to shorten dissolution time, expedite chemical separation, and improve forensic analysis of the nuclear melt glass that is created during the detonation of the device. To expedite this process, an instrument was designed to thermally couple a gas chromatograph (GC) to a time-of-flight inductively coupled plasma time-of-flight mass spectrometer (ICPTOFMS) In order to couple these two instruments, another instrument was designed to provide an isothermal atmosphere between the GC and TOFICPMS to expedite rapid gas separations processes. By using gas separations instead of the current wet chemistry processes, the required separation and analysis time of the melt glass significantly decreases. The new instrument would also provide a more detailed analysis of the elemental and isotopic composition of the melt glass. By completing these tasks simultaneously, this significantly decreases the required time to conduct these separations and improves the elemental and isotopic analysis. 展开更多
关键词 NUCLEAR FORENSICS gas chromatography Mass spectrometry MELT Glass Chemical Separation NUCLEAR Security ELEMENTAL Analysis
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Product Analysis of Supercritical Fischer-Tropsch Synthesis: Utilizing a Unique On-Line and Off-Line Gas Chromatographs Setup in a Bench-Scale Reactor Unit
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作者 Amro Kasht Rehan Hussain +2 位作者 Minhaj Ghouri Jan Blank Nimir O. Elbashir 《American Journal of Analytical Chemistry》 2015年第8期659-676,共18页
The utilization of supercritical fluids (SCF) in the Fischer-Tropsch Synthesis (FTS) further complicates the hydrocarbon products identification and analysis process due to the dilution of hydrocarbon peaks by the pre... The utilization of supercritical fluids (SCF) in the Fischer-Tropsch Synthesis (FTS) further complicates the hydrocarbon products identification and analysis process due to the dilution of hydrocarbon peaks by the predominant solvent peak. Therefore, in this project, a custom-made Gas Chromatography (GC) analysis system was designed and implemented to identify and quantify SCF-FTS products. The FTS products were identified using two different methods. The first was through retention time matching by injecting standard solutions, and the second was through the use of the GC/MS system. The quantification of CO and CH4 was achieved by using external standards, where the CO conversion was calculated by relating the peak area of CO to the peak area of an internal standard (argon) while the CH4 selectivity was calculated by relating the peak area of CH4 to that of CO. After setting and calibrating the GC system, two reaction conditions (gas phase: 240°C, 20 bar syngas with 2:1 H2:CO molar feed ratio and for the supercritical fluids FTS (SCF-FTS): 240°C, 65 bar with 20 bar syngas partial pressure and 2:1 H2:CO molar feed ratio) were used to compare the different FTS reaction media. The comparison between the gas phase FTS and the SCF-FTS showed the following: carbon monoxide conversion was improved by 14% in the SCF-FTS, while the hydrocarbon product profile SCF-FTS showed 78% reduction in light hydrocarbons (C1 - C4) products, 35% increase in middle distillates (C11 - C22) products compared to gas phase FTS. These improvements have resulted in higher chain growth probability for the SCF-FTS (α = 0.85) compared to the gas phase FTS (α = 0.76). These results are generally in agreement with previously reported enhancement in the SCF-FTS[1]. 展开更多
关键词 SUPERCRITICAL Fluids Fischer-Trospch Synthesis gas chromatography Mass spectrometry
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Screening of marine seaweeds for bioactive compound against fish pathogenic bacteria and active fraction analysed by gas chromatography-mass spectrometry
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作者 Rajasekar Thirunavukkarasu Priyadharshini Pandiyan +4 位作者 Kumaran Subaramaniyan Deivasigamani Balaraman Sakthivel Manikkam Balamurugan Sadaiyappan George Edward Gnana Jothi 《Journal of Coastal Life Medicine》 2014年第5期367-375,共9页
Objective:To isolate bioactive molecules from marine seaweeds and check the antimicrobial activity against the fish pathogenic bacteria.Methods:Fresh marine seaweeds Gracilaria edulis,Kappaphycus spicifera,Sargassum w... Objective:To isolate bioactive molecules from marine seaweeds and check the antimicrobial activity against the fish pathogenic bacteria.Methods:Fresh marine seaweeds Gracilaria edulis,Kappaphycus spicifera,Sargassum wightii(S.wightii)were collected.Each seaweed was extracted with different solvents.In the study,test pathogens were collected from microbial type culture collection.Antibacterial activity was carried out by using disc diffusion method and minimum inhibition concentration(MIC)was calculated.Best seaweed was analysed by fourier transform infrared spectroscopy.The cured extract was separated by thin layer chromatography(TLC).Fraction was collected from TLC to check the antimicrobial activity.Best fraction was analysed by gas chromatography mass spectrometer(GCMS).Results:Based on the disc diffusion method,S.wightii showed a better antimicrobial activity than other seaweed extracts.Based on the MIC,methanol extract of S.wightii showed lower MIC than other solvents.S.wightii were separated by TLC.In this TLC,plate showed a two fraction.These two fractions were separated in preparative TLC and checked for their antimicrobial activity.Fraction 2 showed best MIC value against the tested pathogen.Fraction 2 was analysed by GCMS.Based on the GCMS,fraction 2 contains n-hexadecanoic acid(59.44%).Conclusions:From this present study,it can be concluded that S.wightii was potential sources of bioactive compounds. 展开更多
关键词 Marine seaweeds Vibrio sp.fish pathogenic Thin layer chromatography gas chromatography-mass spectrometry
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A Gas Chromatography-Mass Spectrometry‑Based Metabonomic Study on Estimation of Toxicant in Rats
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作者 Yingqiang Fu Xinhua Dai +5 位作者 Fan Chen Yuzi Zheng Shiyong Fang Yang Lin Yi Ye Linchuan Liao 《Journal of Forensic Science and Medicine》 2019年第2期80-86,共7页
The aim of this study was to develop a gas chromatography‑mass spectrometry(GC‑MS)‑based metabolomics method to distinguish different kinds of poisons in the blood.We examined the changes in blood metabolites using GC... The aim of this study was to develop a gas chromatography‑mass spectrometry(GC‑MS)‑based metabolomics method to distinguish different kinds of poisons in the blood.We examined the changes in blood metabolites using GC‑MS following administration of four different poisons(paraquat,dichlorvos,aconitine,and sodium nitrite).The data were analyzed with orthogonal partial least squares.Then,total and single differential metabolite profiles were evaluated with support vector machine(SVM)models.The results showed that various metabolites(5‑ketone proline,1,5‑anhydrohexitol,lactic acid,glycine 2,2‑furoic acid,and 3‑hydroxybutyric acid)were differential between the experimental groups and the control groups.The accuracy rates of the SVM models established using total and single differential metabolites were 80%and 100%,respectively.In conclusion,we successfully developed a poison screening method.The established SVM models can distinguish four kinds of poisons and could be used to establish a complete poison metabonomic information database.Furthermore,some of the metabolites could be biomarkers of these poisons.Finally,both the models and potential biomarkers may reduce the time required for poison detection and provide direction for solving cases and auxiliary diagnosis. 展开更多
关键词 ACONITINE DICHLORVOS gas chromatography‑mass spectrometry METABONOMICS PARAQUAT sodium nitrite
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Gas chromatography mass spectrometry based metabolic profiling reveals biomarkers involved in rice-gall midge interactions 被引量:6
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作者 Ruchi Agarrwal Jagadish Sanmallappa Bentur Suresh Nair 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2014年第9期837-848,共12页
The Asian rice gall midge(Orseolia oryzae WoodMason) is a serious pest of rice that causes huge loss in yield.While feeding inside the susceptible host,maggots secrete substances that facilitate the formation of a h... The Asian rice gall midge(Orseolia oryzae WoodMason) is a serious pest of rice that causes huge loss in yield.While feeding inside the susceptible host,maggots secrete substances that facilitate the formation of a hollow tube-like structure called gall and prevent panicle formation.The present investigation was carried out to get an account of biochemical changes occurring in the rice plant upon gall midge feeding.Metabolic profiling of host tissues from three rice varieties,namely,TN1,Kavya,and RP2068,exposed to gall midge biotype 1(GMB1),was carried out using gas chromatography mass spectrometry(GC-MS).TN1 and GMB1 represented compatible interaction,while Kavya and GMB1 as well as RP2068 and GMB1 represented incompatible interactions.The current study identified several metabolites that could be grouped as resistance,susceptibility,infestation,and host features based on their relative abundance.These may be regarded as biomarkers for insect-plant interaction in general and rice-gall midge interaction in particular. 展开更多
关键词 Biomarkers gas chromatography mass spectrometry insect-plant interaction metabolic profiling METABOLITES rice-gall midge interaction
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Identification of petroleum aromatic fraction by comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry 被引量:6
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作者 WANG HuiTong WENG Na +3 位作者 ZHANG ShuiChang ZHU GuangYou CHEN JianPing WEI CaiYun 《Chinese Science Bulletin》 SCIE EI CAS 2010年第19期2039-2045,共7页
Comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry(GC×GC-TOFMS) is commercially available in the 1990s,with the characteristics of large peak capacity,high resolution,h... Comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry(GC×GC-TOFMS) is commercially available in the 1990s,with the characteristics of large peak capacity,high resolution,high sensitivity,etc.However,its application to the petroleum and geological analyses is just emerging in China and overseas.In this research,the analytical method for petroleum aromatic fraction using GC×GC-TOFMS is set up,via the choice of the column system and optimization of setting parameters,such as temperature programming,modulation time,hot pulse time,flow rate of carrier gas,data acquisition rate and data processing.The results indicate that different polar compounds of aromatic fraction distribute as bands on structured GC×GC chromatogram.Within each band,homologous compounds appear as a roof-tile structure based on the number of substituent residues.The aromatic compounds are identified and characterized according to the GC×GC chromatogram and mass spectra.According to the polarity and the number of rings,aromatic compounds are spatially present on one chromatogram,which directly reflects the distribution characteristics of complex compounds of aromatic hydrocarbons.In addition,quantitative analysis is favored as some overlapped peaks on traditional GC-MS chromatogram have been separated completely on GC×GC.Some heterocyclic atom aromatic compounds at trace level can be clearly identified using this method,for polarity differences from other interfered aromatic compounds.The development of this method and chromatogram recognition offer petroleum geologists a practical example for the application performance of GC×GC-TOFMS. 展开更多
关键词 comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry aromatic compounds heterocycliccompounds petroleum geological experiments
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Qualitative Analysis of A Sulfur-fumigated Chinese Herbal Medicine by Comprehensive Two-Dimensional Gas Chromatography and High-Resolution Time of Flight MassSpectrometry Using Colorized Fuzzy Difference Data Processing 被引量:4
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作者 CAI Hao CAO Gang ZHANG Hong-yan 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2017年第4期261-269,共9页
To investigate the chemical transformation of volatile compounds in sulfur-fumigated Radix Angelicae Sinensis. A comprehensive two-dimensional gas chromatography (GCxGC) and high-resolution time-of-flight mass spectro... To investigate the chemical transformation of volatile compounds in sulfur-fumigated Radix Angelicae Sinensis. A comprehensive two-dimensional gas chromatography (GCxGC) and high-resolution time-of-flight mass spectrometry (HR-TOF/MS) with colorized fuzzy difference (CFD) method was used to investigate the effect of sulfur-fumigation on the volatile components from Radix Angelicae Sinensis. Twenty-five compounds that were found in sun-dried samples disappeared in sulfur-fumigated samples. Seventeen volatile components including two sulfur-containing compounds were newly generated for the first time in volatile oils of sulfur-fumigated Radix Angelicae Sinensis. The strategy can be successfully applied to rapidly and holistically discriminate sun-dried and sulfur-fumigated Radix Angelicae Sinensis. GCxGC-HR-TOF/MS based CFD is a powerful and feasible approach for the global quality evaluation of Radix Angelicae Sinensis as well as other herbal medicines. 展开更多
关键词 Radix Angelicae Sinensis comprehensive two-dimensional gas chromatography and high-resolution time-of-flight mass spectrometry colorized fuzzy difference volatile components
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Analysis of nitrobenzene compounds in water and soil samples by graphene composite-based solid-phase microextraction coupled with gas chromatography–mass spectrometry 被引量:5
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作者 Gui-Jiang Zhang Xin Zhou +3 位作者 Xiao-Huan Zang Zhi Li Chun Wang Zhi Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第11期1449-1454,共6页
In this work, solid-phase microextraction coupled with gas chromatography–mass spectrometry was developed to determine trace levels of nitrobenzene compounds in water and soil samples. Graphene was chosen as the extr... In this work, solid-phase microextraction coupled with gas chromatography–mass spectrometry was developed to determine trace levels of nitrobenzene compounds in water and soil samples. Graphene was chosen as the extraction material and its composite was coated on a stainless steel wire through sol–gel technique for the solid phase microextraction. The key parameters influencing the extraction efficiency were optimized. Under the optimal conditions, the linearity for the compounds was observed in the range of 0.02–15.0 mg/L for water samples, and 0.2–60.0 mg/kg for soil samples, with the correlation coefficients(r) of 0.9966–0.9987. The limits of detection of the method were 0.0025–0.005 mg/L for water samples, and 0.02–0.04 mg/kg for soil samples. The recoveries for the spiked samples were in the range of 72.0%–113.2%, and the precision, expressed as the relative standard deviations, was less than 12.1%. 展开更多
关键词 Graphene Solid-phase microextraction Nitrobenzene compounds gas chromatography–mass spectrometry
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