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GC-MS analysis of volatile compounds of Perilla frutescens Britton var. Japonica accessions: morphological and seasonal variability 被引量:7
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作者 Bimal Kumar Ghimire Ji Hye Yoo +1 位作者 Chang Yeon Yu Ill-Min Chung 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2017年第7期705-714,共10页
Objective: To investigate the composition of volatile compounds in the different accessions of Perilla frutescens(P. frutescens) collected from various habitats of China and Japan. Methods: In the present study, the e... Objective: To investigate the composition of volatile compounds in the different accessions of Perilla frutescens(P. frutescens) collected from various habitats of China and Japan. Methods: In the present study, the essential oil from the leaves of P. frutescens cultivars from China and Japan was extracted by hydro-distillation and the chemical composition and concentration of the volatile components present in the oils were determined by gas chromatography–mass spectrometry(GC–MS) analysis. Results: Among the volatile components, the major proportion was of perilla ketone, which was followed by elemicin and beta-caryophyllene in the Chinese Perilla cultivars. The main component in the oil extracted from the Japanese accessions was myristicin, which was followed by perilla ketone and beta-caryophyllene. We could distinguish seven chemotypes, namely the perilla ketone(PK) type, perilla ketone, myristicin(PM) type, perilla ketone, unknown(PU) type, perilla ketone, beta-caryophyllene, myristicine(PB) type, perilla ketone, myristicin, unknown(PMU) type, perilla ketone, elemicine, myristicin, beta-caryophyllene(PEMB) type, and the perilla ketone, limonene, betacryophyllene, myristicin(L) type. Most of the accessions possessed higher essential oil content before the flowering time than at the flowering stage. The average plant height, leaf length, leaf width of the Chinese accessions was higher than those of the Japanese accessions. Conclusion:The results revealed that the harvest time and geographical origin caused polymorphisms in the essential oil composition and morphological traits in the Perilla accessions originating from China and Japan. Therefore, these chemotypes with desirable characters might be useful for industrial exploitation and for determining the harvest time. 展开更多
关键词 Perilla frutescens Essential oil gc–MS analysis Morphological character Harvesting time
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GC/MS Analysis of Organic Compounds in Hot Water-Extractable Fraction from Shenfu Coal 被引量:7
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作者 LI Bao-min YUAN Cheng ZONG Zhi-min CAO Jing-pei LIU Guang-feng WEI Xian-yong 《Journal of China University of Mining and Technology》 EI 2007年第3期354-357,共4页
Shenfu Coal was extracted with hot pure water and slurry was isolated. The concentrated benzene-soluble fraction (CBSF) was analyzed with GC/MS and four types of organic compounds (OCs) were detected: HACOCs,DTEs,DMDT... Shenfu Coal was extracted with hot pure water and slurry was isolated. The concentrated benzene-soluble fraction (CBSF) was analyzed with GC/MS and four types of organic compounds (OCs) were detected: HACOCs,DTEs,DMDT and LCAs. The amount of benzyl benzoate which is the most abundant OC was calculated by an inter-nal standard method with an indicated amount of BP. The broken hydrogen bonds and ether bonds were responsible for the extraction of OCs from the coal .DTEs,DMDT and LCAs are essentially insoluble in water,whereas they are soluble,probably owing to intermolecular interaction of OCs with HACOCs. 展开更多
关键词 thermal extraction gc/MS analysis water-soluble fraction benzene-soluble fraction
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Chemical composition, antioxidant activity and GC-MS analysis of juice and peel oil of grapefruit varieties cultivated in India 被引量:5
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作者 Shahnawaz Ahmed H S Rattanpal +2 位作者 Khalid Gul Rouf Ahmad Dar Akash Sharma 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第7期1634-1642,共9页
Citrus family especially Grapefruit,has attained considerable attention due to the presence of a number of essential components that have cardiovascular and anti-hypertensive properties.The juice and essential oil ext... Citrus family especially Grapefruit,has attained considerable attention due to the presence of a number of essential components that have cardiovascular and anti-hypertensive properties.The juice and essential oil extracted from eight recently released grapefruit cultivars were used to study physicochemical and antioxidant properties.The total soluble solids(TSS),titratable acidity(TA) and pH of juice samples extracted from various grapefruit varieties differed significantly.The refractive index,specific gravity and optical rotation values for the oil varied from 1.473 to 1.396,0.863 to 0.847 and +93 to +86,respectively.The percent 2,2-diphenyl-1-picrylhydrazyl radical activity(% DPPH activity) and ferric reducing antioxidant power(FRAP) values for grapefruit juice and peel oil varied from 24.06 to 18.79,2.91 to 1.44 mmol g^–1 and 84.87 to 74.73,7.76 to 5.73 mmol g^-1,respectively.There were significant differences in physicochemical,antioxidant properties and volatile profiles of extracted juice and oil.The oil exhibited higher DPPH and FRAP values than the juice.Among different components identified which accounted for over 99% of the volatile fraction,limonene,myrcene,and benzopyran were major components in all oil samples. 展开更多
关键词 GRAPEFRUIT JUICE essential oil PHYSICOCHEMICAL PROPERTIES antioxidant PROPERTIES gc-MS analysis
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Analysis of vapor phase organics in air of Beijing, Langfang and Tianjin by capillary GC and GC/MS
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作者 Lai Cong, Wang Dechun, Wei Rurong and Yang WenxiangResearch Center for Eco-Environmental Sciences,Academia Sinica.P.O.Box 934,Beijing 100083,China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1990年第1期99-108,共10页
The vapor phase organics (VPOs) in the air of Beijing, Langfang and Tianjin were detected by a capillary gas chromatography and GC/MS during the winter and the summer separately. The tentatively identified compounds i... The vapor phase organics (VPOs) in the air of Beijing, Langfang and Tianjin were detected by a capillary gas chromatography and GC/MS during the winter and the summer separately. The tentatively identified compounds include alkanes, cyclic hydrocarbons, alkenes, aromatics, acids, alcohols, aldehydes, ketones, esters, halocarbons and so on. The numbers of VPOs found are 118 in Beijing, 83 in Lang-fang and 65 in Tianjin in the winter, and 56, 39 and 72 in the summer respectively. Based on the data of some representative compounds determined quantitatively by GC and GC/MS, a profile of organic pollution in the air of the three cities is presented. 展开更多
关键词 vapor organics air pollution gc gc/MS analysis
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GC–MS analysis of bioactive compounds present in different extracts of an endemic plant Broussonetia luzonica (Blanco) (Moraceae) leaves
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作者 Franelyne Pataueg Casuga Agnes Llamasares Castillo Mary Jho-Anne Tolentino Corpuz 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2016年第11期957-961,共5页
Objective: To investigate and characterize the chemical composition of the different crude extracts from the leaves of Broussonetia luzonica(Blanco)(Moraceae)(B. luzonica), an endemic plant in the Philippines.Methods:... Objective: To investigate and characterize the chemical composition of the different crude extracts from the leaves of Broussonetia luzonica(Blanco)(Moraceae)(B. luzonica), an endemic plant in the Philippines.Methods: The air dried leaves were powdered and subjected to selective sequential extraction using solvents of increasing polarity through percolation, namely, n-hexane,ethyl acetate and methanol to obtain three different extracts. Then, each of the extracts was further subjected to gas chromatography–mass spectrometry.Results: Qualitative determination of the different biologically active compounds from crude extracts of B. luzonica using gas chromatography–mass spectrometry revealed different types of high and low molecular weight chemical entities with varying quantities present in each of the extracts. These chemical compounds are considered biologically and pharmacologically important. Furthermore, the three different extracts possess unique physicochemical characteristics which may be attributed to the compounds naturally present in significant quantities in the leaves of B. luzonica.Conclusions: The three extracts possess major bioactive compounds that were identified and characterized spectroscopically. Thus, identification of different biologically active compounds in the extracts of B. luzonica leaves warrants further biological and pharmacological studies. 展开更多
关键词 Broussonetia luzonica(Blanco) Selective sequential extraction gc–MS analysis ENDEMIC PERCOLATION
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Phytochemical Analysis and Antimicrobial Activity of Lawsonia inermis Leaf Extracts from Burkina Faso
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作者 Ollo Youl Soumaïla Konaté +10 位作者 Ernest N. Sombié Rainatou Boly Boukaré Kaboré Moumouni Koala Arouna Zoungrana Saybou Savadogo Christian Marc Tahita Innocent Valea Halidou Tinto Adama Hilou Maminata Traoré-Coulibaly 《American Journal of Plant Sciences》 CAS 2024年第7期552-576,共25页
Lawsonia inermis is a hairless plant growing in various regions of North Africa, the Indian subcontinent, and the Middle East. It possesses many medicinal attributes, including curative properties against infectious d... Lawsonia inermis is a hairless plant growing in various regions of North Africa, the Indian subcontinent, and the Middle East. It possesses many medicinal attributes, including curative properties against infectious dermatoses. This study was carried out to evaluate the phytochemical profile of the crude ethanolic extract of the plant leaves and its fractions as well as their antimicrobial activities. The phytochemical profile was performed using high-performance thin-layer chromatography (HPTLC), gas chromatography-mass spectrometry (GC-MS), and high-performance liquid chromatography (HPLC). Additionally, the phenolic and flavonoid contents were determined using the Folin-Ciocalteu spectrophotometric and the aluminum trichloride methods. Antimicrobial activity was tested using disc diffusion and microdilution methods. The presence of flavonoids, tannins, sterols, and triterpenes was revealed. GC-MS detected twelve compounds main compounds consisting of saturated and unsaturated fatty acids and phenolic and terpenoid compounds among twenty-seven components. HPLC also detected high contents of phenolic acids and flavonoids. The most abundant triterpene and sterols were ursolic acid (around 43.14 g/100g DW, 13.9 g/100g dry weight (DW), and 0.68 g/100g DW) in the crude ethanolic extract of leaves (FeLi), hexane fraction (FHLi) and dichloromethane fraction (FDLi), respectively and, β-sitosterol in FeLi (56.7 mg/100g DW), FHLi (10.55 g/100g DW), FDLi (106.1 mg/100g DW) and butanol fraction (FBLi) (357.4 mg/100g DW). Among the flavonoids, rutin = 3.24 g/100g and quercetin = 0.63 g/100g in the ethanolic extract, rutin = 15.73 g/100g in the dichloromethane fraction, and rutin = 0.23 g/100g) in the aqueous fraction;and among phenolic compounds, caffeic acid (37.65 g/100g DW) and vanillic acid (22.70 g/100g DW) were the most important in the ethyl acetate fraction (FAeLi). All organic fractions exhibited interesting antibacterial and antifungal activities against the tested strains, with the best activity recorded with the dichloromethane and ethyl acetate fractions. The leaf extracts’ phytochemical profile and antimicrobial activity support the use of Lawsonia inermis against infectious skin diseases. 展开更多
关键词 Lawsonia inermis Phytochemical Profile HPLC gc-MS analysis Antimicrobial Activity
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Published the papers of GC-MS analysis—Chemical drug
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《Journal of Pharmaceutical Analysis》 SCIE CAS 2011年第1期69-70,共2页
Song Qi, Liu Hu; Gao Shu. Screening and quantitative analysis of volatile markers in the breath of patients with breast cancer Acta Universitatis Medicinalis Anhui, 2010, 45(01) :76-79.
关键词 Chemical drug Published the papers of gc-MS analysis gc MS
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Antibacterial, Antioxidant Activities and GC-MS Analysis of Dichrostachys cinera (L.) Ethanolic Leaves Extract
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作者 Sitelbanat Yassin Mohamed Abubker +4 位作者 Anwar Mohamed Selma Omer Salah Humeada Elhadi M. M. Ahmed Mirghani Abd Alrahman 《Pharmacology & Pharmacy》 CAS 2022年第12期545-557,共13页
Traditional medicinal plants are one of the potential sources of antimicrobial drugs and there is a great concern in the use and development of herbal medicine for the treatment of various infections. This study aimed... Traditional medicinal plants are one of the potential sources of antimicrobial drugs and there is a great concern in the use and development of herbal medicine for the treatment of various infections. This study aimed to evaluate the antibacterial, and antioxidant activities of Dichrostachys cinera ethanolic leaves extract and to determine the components of the crude extract. D. cinera extract was evaluated against Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, and Pseudomonas aeruginosa ATCC 27853. The antibacterial, antioxidant activities and active constituents were determined using standard methods. Antibacterial activity of the crude extract findings showed that all bacterial candidates were susceptible where S. aureus represent MIC at 12.5 mg/ml and MBC at 25 mg/ml, E. coli and P. aeruginosa both showed MIC 25 mg/ml and MBC 50 mg/ml. In the free radical scavenging assay of the extract and the standard quercetin at concentrations of 250 μg/ml, 125 μg/ml, 50 μg/ml, 10 μg/ml, and 5 μg/ml. The radical scavenging activity for the extract was about 92%, 89.6%, 86.8%, 82.8% and 37.8% respectively, compared to quercetin which gave 89.7%, 85.8%, 62.1%, 55.5%, and 45% radical scavenging activity. The GC-Ms analysis of the total constituents demonstrated that 1,6-Anhydro-2,4-dideoxy-.beta.-D-ribo-hexo (21.26%) with different peaks, followed by Glycerin (11.56%), 1,2,3-Cyclopentanetriol (10.18%), 8,11,14-Eicosatrienoic acid, (Z,Z,Z)-(6.18%), 1H-Pyrrole, 1-methyl-(6.08%), Phytol (5.91%) and 7-Bromo-6-(2-diethylaminoethoxy)-2,3-dihyd (5.44%) as major components in the extract. Finally, this study provided useful information on the therapeutic potential of D. cinera as an antibacterial agent and recommended to be evaluated against a wide range of Bacterial and fungal strains using different solvents and different parts from the plant. 展开更多
关键词 Dichrostachys cinera Antibacterial Activity ANTIOXIDANT gc MS analysis
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Evaluation of the Equality of Non-Polar Capillary Columns in GC/MS Analysis of Food Contact Plastics
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作者 Motoh Mutsuga Miku Yamaguchi +1 位作者 Yutaka Abe Hiroshi Akiyama 《American Journal of Analytical Chemistry》 2013年第9期476-487,共12页
Non-polar capillary columns for GC/MS are widely utilized in the analysis of additives for food contact materials. Though various kinds of non-polar capillary columns are commercially available, the equality of their ... Non-polar capillary columns for GC/MS are widely utilized in the analysis of additives for food contact materials. Though various kinds of non-polar capillary columns are commercially available, the equality of their performance has not been verified. Herein, ninety-six additives for food contact plastics were analyzed using fifteen kinds of columns, and the peak separation, retention times, and peak areas of each additive were compared. The additives, with various chemical properties, comprised forty four plasticizers, twenty lubricants, twenty antioxidants, nine ultraviolet absorbers, and three other compounds. 10 μg.mL-1 test solutions were prepared in acetone, and injected to the GC/MS. The fifteen columns were classified into five categories based on the chromatogram pattern and peak separation. To facilitate comparison of the retention time and detection sensitivity of the columns for the additives, the relative retention time (RRT) and relative peak area (RPA) were calculated by using dibutylphthalate or 4-tert-butylphenylsalicylate as an internal standard. The RRTs of the additives on each column were essentially similar. However, the RRT of the additives which were detected in the later stages differed slightly. Although the RPA of the plasticizers and lubricants were roughly similar, column-to-column differences were observed for certain additives, such as antioxidants and ultraviolet absorbers. Furthermore, certain fatty acids, antioxidants, two plasticizers, and two benzophenone type ultraviolet absorbers were not detected in the chromatograms of two columns. 展开更多
关键词 NON-POLAR CAPILLARY Column gc/MS analysis Additives for Food Contact PLASTICS RELATIVE RETENTION Time RELATIVE Peak Area
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LOCATION OF DOUBLE BOND POSITION OF INSECT SEX PHEROMONE BY GC/MS ANALYSIS WITH CHEMICAL IONIZATION
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作者 Fan Lei KONG Jiangsu Institute of Ecomomes,Jintan Jiangsu,213200 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第2期109-112,共4页
Ozonolysis products of four lepidopteral pheromone were identified by methane CI-MS.The spectra obtained were notably simpler than those of EI-MS,the peak of molecular ion was normally close to the base peak,and the c... Ozonolysis products of four lepidopteral pheromone were identified by methane CI-MS.The spectra obtained were notably simpler than those of EI-MS,the peak of molecular ion was normally close to the base peak,and the characteristic fragment ions were high in m/z,thereby the interpretation was facilitated. 展开更多
关键词 MS gc LOCATION OF DOUBLE BOND POSITION OF INSECT SEX PHEROMONE BY gc/MS analysis WITH CHEMICAL IONIZATION
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GC-MS Analysis and in Vitro Antimicrobial Susceptibility of <i>Foeniculum vulgare</i>Seed Essential Oil 被引量:1
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作者 Ravi Kant Upadhyay 《American Journal of Plant Sciences》 2015年第7期1058-1068,共11页
Essential oil from seeds of Foeniculum vulgare was extracted on Clevenger apparatus. Essential oil was analyzed on Gas-Chromatography-Mass spectrometry (GC-MS) from which thirty six components were identified, among w... Essential oil from seeds of Foeniculum vulgare was extracted on Clevenger apparatus. Essential oil was analyzed on Gas-Chromatography-Mass spectrometry (GC-MS) from which thirty six components were identified, among which 6 major and 30 minor components having different structural formulae and molecular weight representing total 99.98% of oil. Essential was investigated for its antibacterial and antifungal activity against seven infectious microbial pathogens. Paper disc diffusion and serial micro-dilution assays were performed for the determination of inhibition zone (DIZ) diameters and minimal inhibitory concentration, respectively. The Foeniculum vulgare essential oil showed the Diameter of Inhibition Zone (DIZ) ranging from 19.4 ± 0.07 - 26.4 ± 0.09 mm at a concentration level of 28 μg/disc in all the ten strains tested. The minimum inhibitory concentration (MIC) of essential oil against bacterial and fungal strains was obtained in the range of 7.0 - 56 μg/ml. Antibacterial and antifungal activity of Foeniculum vulgare essential oil is due to the presence of certain secondary plant metabolites such as terpenoids, steroids and flavonoids, esters and acids which are identified in the essential oil. The oil components can be further studied for their biological activity and overcome the problem of drug resistance in microbes. 展开更多
关键词 ANTIMICROBIAL Activity Foeniculum vulgare Essential Oil gc-MS analysis MIC MBC MFC DIZ
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Study on Fractional Separation and GC-MS Analysis of Flash Coal Tar Pyrolysed at Low Temperatures
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作者 吴国光 王祖讷 《International Journal of Mining Science and Technology》 SCIE EI 1997年第1期99-102,共4页
The composition of low temperature pyrolysis coal tar has an effect on its further processing and reasomble utlization In this paper, the compeition or coal tars produced from both low temperature pyroysis in a fluidi... The composition of low temperature pyrolysis coal tar has an effect on its further processing and reasomble utlization In this paper, the compeition or coal tars produced from both low temperature pyroysis in a fluidized bed aud flash pyrolysis with solid heat carrier have been investigated by the methch of fractional seperation and Gas Chromatography-Mass Spectrometry (GC-MS)- It is observed that the degree of coalification maceral and secondary reaction temperature (freeboard temperature in a fluidized bed) have some iufluence on the composition of coal tars- The main compoundes are phenol cresols,xylenols, naphthalene, alkylnaphthalenes, antbraceue, phenanthrene,acenaphthylene, fluoren, indene and so 展开更多
关键词 low temperature and FLASH PYROLYSIS COAL TAR FRACTIONAL SEPARATION gc-MS analysis
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GC-MS analysis of essential oil of <i>Paeonia suffruticosa</i>Andrews from ZhaoFen and RouFurong flowers in China
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作者 Weiping Yin Wenlu Duan +3 位作者 Pu Liu Ruixue Deng Yunlai Ren Shuang Zhao 《Natural Science》 2012年第8期552-554,共3页
The flowers of ZhaoFen and RouFurong may contain essential oils with natural aromatic ingredients. In the present work, the chemical compositions of essential oil of Paeonia suffruticosa Andrews from the flowers of Zh... The flowers of ZhaoFen and RouFurong may contain essential oils with natural aromatic ingredients. In the present work, the chemical compositions of essential oil of Paeonia suffruticosa Andrews from the flowers of ZhaoFen and RouFurong grown only in China were investigated by GC-MS analysis. The results indicate that there are 27 constituents in ZhaoFen and 29 constituents in RouFurong, which account for 96.04% and 95.90% of the oils of ZhaoFen and RouFurong, respectively. The major components of the essential oils are character-rized by oxygenated terpenols, and their content is, respectively, 85.06% and 83.47%. The essential oil of Paeonia suffruticosa Andrews was reported for the first time on the aerial parts. 展开更多
关键词 Chemical Composition ESSENTIAL Oil The FLOWERS of PAEONIA suffruticosa Andrews gc-MS analysis Oxygenated Terpenol
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The composition analysis of coal-derived light oil 被引量:5
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作者 高振楠 刘立麟 +1 位作者 朱肖曼 李文博 《Journal of Coal Science & Engineering(China)》 2008年第1期136-139,共4页
The composition of coal-derived light oil (IBP-220℃) was separated into 5 fractions by atmospheric distillation and analyzed by gas chromatography/mass spec- trometry (GC/MS).The light oil was made at 0.1 t/d coal di... The composition of coal-derived light oil (IBP-220℃) was separated into 5 fractions by atmospheric distillation and analyzed by gas chromatography/mass spec- trometry (GC/MS).The light oil was made at 0.1 t/d coal direct liquefaction bench scale unit (BSU) at China Coal Research Institute (CCRI).Six groups of organics,including acyclic hydrocarbon,alicyclic hydrocarbon,aromatics,phenols,polynuclear aromatics and heterocyclics,were found and 80 compounds were tentatively identified in total.Alicyclic hydrocarbon is the main component of the light oil compared to other groups whether in relative mass percentage or the number of compounds in group.The predominant oxy- gen-contained compound is phenols,and the nitrogen-containing compound is pyridine. No sulfur-containing compound is detected. 展开更多
关键词 coal-derived liquid coal direct liquefaction gc/MS component analysis
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Component analysis of volatile oil from Illicium Verum Hook. f. 被引量:2
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作者 阎建辉 肖旭贤 黄可龙 《Journal of Central South University of Technology》 EI 2002年第3期173-176,共4页
Volatile oil was extracted from Illicium Verum Hook. f. by using steam distillation. 41 kinds of compounds were separated and identified by GC/MS, and their relative contents were determined by normalization method. A... Volatile oil was extracted from Illicium Verum Hook. f. by using steam distillation. 41 kinds of compounds were separated and identified by GC/MS, and their relative contents were determined by normalization method. Among 41 identified compounds, there are 14 hydrocarbon components and 22 oxygenated hydrocarbon derivatives, and a small amount of nitrogenous compounds. The main component is anethole, accoun ting for 76.23%, and the other components such as anisyl acetone, anisaldehyde, p allylanisole, p cumic aldehyde and p allylpen take up more than 10%. 展开更多
关键词 Illicium Verum Hook. f. volatile oil gc/MS analysis
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Gas chromatography-mass spectrometry analysis of various organic extracts of Merremia borneensis from Sabah 被引量:1
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作者 M Amzad Hossain Muhammad Dawood Shah Mahyar Sakari 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第8期637-641,共5页
Objective:To analyse the chemical composition of different extracts of Merremia borneensis(M. borneensis) by gas chromatography-mass spectrometry(GC-MS).Methods:The dried leaves powder was extracted with methanol at r... Objective:To analyse the chemical composition of different extracts of Merremia borneensis(M. borneensis) by gas chromatography-mass spectrometry(GC-MS).Methods:The dried leaves powder was extracted with methanol at room temperature by using Soxhlet extractor.Methanol crude extracts of M.borneensis were extrastel with hexane,chloroform,ethyl acetate and butanol. Results:Qualitative analyses of various organic crude extracts showed that majority of these are flavonoids,terpeniods,alkaloids and glycosides.Most of the identified compounds by GCMS are biologically important.Further the M.borneensii leaf possesses certain characteristics that can be ascribed to cultivation on a domestic plantation.Conclusions:The suitable extracts for respective compounds can be chosen on the basis of above GC-MS analysis.All the major compounds from different extracts are biologically active molecules.Thus the identification of a good number of compounds from various extracts M.borneensis might have some ecological significance. 展开更多
关键词 Merremia borneensis ORGANIC EXTRACTS Qualilalive analysis gc-MS
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Analysis of α, β, γ-hexachlorocyclohexanes in water by novel activated carbon fiber-solid phase microextraction coupled with gas chromatography—mass spectrometry 被引量:4
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作者 SUNTong-hua FANGNeng-hu +2 位作者 ZHUNan-wen WANGYa-lin JIAJin-ping 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第6期945-949,共5页
A fast and simple method for determination of α, β, γ-hexachlorocyclohexanes (HCHs) in water using activated carbon fiber-solid phase microextraction(ACF-SPME) were studied. Results showed the performance of adsorp... A fast and simple method for determination of α, β, γ-hexachlorocyclohexanes (HCHs) in water using activated carbon fiber-solid phase microextraction(ACF-SPME) were studied. Results showed the performance of adsorption and desorption of three HCHs on ACF were excellent. A wide linear range from 10 to 100 μg/L and detection limits of the ng/L level were obtained using ACF-SPME with GC-MS in selected ion monitoring(SIM) acquisition mode. The proposed method was also successfully applied for determination of three HCHs in tap water. Compared to commercial fibers, ACF showed some advantages such as better resistance to solvents, higher thermal stability, longer lifetime and lower cost. The data demonstrated that GC-MS with ACF-SPME is well suitable for the analysis of HCHs in water. 展开更多
关键词 solid phase microextraction activated carbon fiber residue analysis α β γ-hexachlorocyclohexanes gc-MS
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HER2 discordance between paired primary gastric cancer and metastasis:a meta-analysis 被引量:2
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作者 Zhi Peng Jianling Zou +5 位作者 Xiaotian Zhang Yehong Yang Jing Gao Yilin Li Yanyan Li Lin Shen 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2015年第2期163-171,共9页
Background: A number of studies have examined human epidermal growth factor receptor 2 (HER2) status in primary gastric cancer (GC) and associated metastasis, some showed their great concordance in FIER2 expressi... Background: A number of studies have examined human epidermal growth factor receptor 2 (HER2) status in primary gastric cancer (GC) and associated metastasis, some showed their great concordance in FIER2 expression, but others demonstrated notable discordance. There is still little consensus on HER2 discordance, therefore, a systematic review and meta-analysis was conducted to assess the status on HER2 discordance between primary GC and its paired metastasis. Methods: PubMed, EMBASE, ASCO and The Cochrane Library were searched for studies that explored the concordance between primary tumor and metastasis in patients with GC up to 10 March, 2014. Data of discordance of HER2 between primary GC and corresponding metastasis were extracted from the publications and random-effects models were used to estimate pooled discordance proportions. Results: Eighteen articles including 1,867 patients were included for the meta-analysis in accordance with the selection criteria. Pooled discordance proportions were 7% [95% confidence interval (CI): 5-10%] for HER2 status. Pooled proportions of tumors shifting from positive to negative and from negative to positive were 17% (95% CI: 7-29%) and 4% (95% CI: 2-6%) respectively. No publication bias was found in the meta-analysis. Conclusions: The discordance of HER2 status is not rare in primary and metastatic GC through our metaanalysis. Prospective studies are needed to testify the clinical significance of the discordance of HER2 status. 展开更多
关键词 Gastric cancer gc human epidermal growth factor receptor 2 (HER2) DISCORDANCE META-analysis
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GAS CHROMATOGRAPHIC-MASS SPECTROMETRIC ANALYSIS OF ANABOLIC STEROIDS IN HUMAN URINE
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作者 Ji ZHANG Chun Sheng LIU Tong Hui ZHOU (Institute of Materia Medica,1 Xian Nong Tan Street,Beijing 100050,P.R.China)Yi Zhong ZHANG Chang Jiu ZHANG Li YE (+ National Research Institute of Sports Medicine,11 Tiyuguan Road,Beijing 100061) 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第2期143-146,共4页
A new GC/MS method for detection and identification of 19 anabolic steroids in human urine is presented.The procedure involves adsorption and isolation on a macroporous XAD-2 resin,enzymatic hydrolysis,alkaline extrac... A new GC/MS method for detection and identification of 19 anabolic steroids in human urine is presented.The procedure involves adsorption and isolation on a macroporous XAD-2 resin,enzymatic hydrolysis,alkaline extraction,derivatization,GC separation and MS detec- tion.Gas chromatographic-mass spectrometric data illustrate artifacts arising from enzymatic hydrolysis of steroid glucuronides and the structural characterization of their metabolites. Using this method,metabolic studies of these steroids in human urine were made after their ingestion by normal and healthy male volunteers.This method was proven to be suitable for large-scale routine analysis of anabolic steroids and was used successfully in passing the doping control test held by the Medical Commission of the International Olympic Committee. 展开更多
关键词 GAS CHROMATOGRAPHIC-MASS SPECTROMETRIC analysis OF ANABOLIC STEROIDS IN HUMAN URINE der gc
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UHAS-MIDA Software Package: Mass Isotopomer Distribution Analysis-Applying the Inverse Matrix for the Determination of Stable Isotopes of Chromium Distribution during Red Blood Cell Labelling
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作者 Daniel A. Abaye Emmanuel B. Odoom +3 位作者 Ernest Y. Boateng Irene A. Agbo John-Bosco Diekuu Samuel Agana 《Journal of Data Analysis and Information Processing》 2022年第2期142-154,共13页
Clinical assessment of fluid volume status in children during malaria can be taxing and often inaccurate. During malaria, changes in fluid volume are rather multifarious and estimating this parameter, especially in si... Clinical assessment of fluid volume status in children during malaria can be taxing and often inaccurate. During malaria, changes in fluid volume are rather multifarious and estimating this parameter, especially in sick children is very challenging for clinicians who frequently rely on indices such as long capillary refill times, tachycardia, central venous pressure and decreased urine volume as guides. Here, we present the UHAS-MIDA, an open-source software tool that calculates the red blood cell (RBC) concentration and blood volume during malaria in children determined using a stable isotope of chromium (<sup>53</sup>Cr as the label) by gas chromatography-mass spectrometry in selective ion monitoring (GC/MS-SIM) analysis. A key component involves the determination of the compositions of the most abundant naturally occurring isotopes of Cr (<sup>50</sup>Cr, <sup>52</sup>Cr, <sup>53</sup>Cr), and converting the proportions into a 3 × 3 matrix. To estimate unknown proportions of chromium isotopic mixtures from the measured abundances of three ions, an inverse matrix was calculated. The inverse together with several inputs is then used to calculate the corrected MS ion abundances. Thus, we constructed the software tool UHAS- MIDA using HTML, CSS/Bootstrap, JavaScript, and PHP scripting languages. The tool enables the user to efficiently determine RBC concentration and fluid volume. The source code, binary packages and associated materials for UHAS-MIDA are freely available at https://github.com/bentil078/Abaye-et-al_UHASmida 展开更多
关键词 Mass Isotopomer Distribution analysis Inverse Matrix gc/MS Chromium Stable Isotopes Blood Volume Red Blood Cell Mass
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