Nowadays,natural rubber(NR)is an indispensable material for industrial production and peoples’daily utilization.The root of Taraxacum kok-saghyz(TKS)contains a large amount of NR,which is potentially to be an alterna...Nowadays,natural rubber(NR)is an indispensable material for industrial production and peoples’daily utilization.The root of Taraxacum kok-saghyz(TKS)contains a large amount of NR,which is potentially to be an alternative rubber source of conventional Hevea brasiliensis(HB).In order to find a convenient,fast and green method for qualitative and quantitative analysis of NR in TKS,a pyrolysis gas chromatography-mass spectrometric(Py-GCMS)method was developed accordingly.The results indicated that the main products of TKS rubber after pyrolysis were isoprene and limonene,respectively,and the limit of detection(LOD)of TKS rubber was 2.603 mg/g.The ratios of NR mass fractions in TKSs by Py-GC-MS ranged from 1.20%±0.20%to 8.61%±0.28%.The developed method has been used for determination of actual TKS samples and can be further applied to the field test for rapid breeding and large-scale cultivation of TKS thereof.展开更多
This study examined the EAG(Electroantennogram)responses of Stilpnotia candida to a mix of host plant volatiles and to provide a foundation for the development of plant-derived attractants.During the peak period of ad...This study examined the EAG(Electroantennogram)responses of Stilpnotia candida to a mix of host plant volatiles and to provide a foundation for the development of plant-derived attractants.During the peak period of adult eclosion,gas chromatography–mass spectrometry analyzed and identified the volatiles emitted by Populus×beijingensis found in Xizang.Based on the preliminary EAG experiments and the GC‒MS results,a blending scheme was developed.EAG and Y-tube-olfactometry were employed to measure the electrophysiological and behavioural responses of unmated males and females 24 h after eclosion 10 blends of volatiles derived from five host plants.The GC–MS analysis revealed 22 volatile compounds from Populus×beijingensis leaves,composed of esters,hydrocarbons,terpenoids,alcohols,phenols,and ether.The results indicated that all 10 blending schemes produced EAG responses in mature S.candida.The concentration thresholds were between 1 and 10μg·μL^(-1),above the optimal concentration,and a corresponding decrease in EAG was observed.According to intergroup comparisons,mature S.candida had more pronounced EAG responses.Under different concentrations,there were significant differences in the EAG from male and female S.candida to each blending scheme.Behavioural response tests indicated that schemes 2,7,and 8 exhibited significantly greater attractiveness to adult S.candida.The combined results from the EAG and behavioral response experiments demonstrated that unmated male and female adult S.candida have varying degrees of sensitivity to the volatile compounds from the 10 blending schemes specific to Xizangan Populus×beijingensis.Schemes 2,7,and 8 showed robust EAG responses and attractive behavioural responses to both male and female adult S.candida.展开更多
Molecular biomarker and whole oil carbon isotope(δ^(13)C_(oil)) analyses were conducted on eleven typical crude oils from the Qiongdongnan Basin to investigate their biological sources and depositional environments. ...Molecular biomarker and whole oil carbon isotope(δ^(13)C_(oil)) analyses were conducted on eleven typical crude oils from the Qiongdongnan Basin to investigate their biological sources and depositional environments. Saturated hydrocarbon biomarkers in most samples are characterized by angiosperm-derived compounds, with aromatic compounds dominated by the naphthalene, phenanthrene, biphenyl, and fluorene series. The related source rocks of these oils were mainly deposited under oxic condition, but a subanoxic-suboxic and enclosed water column condition in the Central Depression during Oligocene.The identification of simonellite and related compounds in the aromatic fractions provides reliable evidence for the input of coniferous gymnosperms. Cadalene may also have a potential association with gymnosperms since it shows a strong positive correlation with simonellite. Evidence from density, nalkanes, short-chain alkylbenzenes and secondary brine inclusions indicates that the unique crude oil B13-1 may have suffered from thermal alteration. These crude oils(excluding B13-1) can be classified into four types based on the δ^(13)C_(oil)values and molecular biomarkers. Type A oil(solely S34-3) is characterized by non-angiosperm plants, with minor dinoflagellates and increasing contribution from conifer gymnosperms than others. Type B oils(L17-2, L18-1, L25-1, and L25-1W) show heavy δ^(13)C_(oil)(-24 ‰to-25 ‰) and mixed contributions from both angiosperms and marine algae, with the marine algae contribution increasing. Type C oils(L13-2 and B21-1) share similar biological sources with Type B, but the moderately δ^(13)C_(oil)(-25‰ to-26‰) and high level of terrestrial biomarkers suggesting a predominant contribution of angiosperms. Type D oils(Y13-1a, Y13-1b, and Y13-4) possess the lightestδ^(13)C_(oil)(mainly below-26‰) and are primarily derived from angiosperms, with mangrove vegetation playing an important role. Spearman correlation analysis among 14 source biomarker parameters withδ^(13)C_(oil)and geological setting of related source rocks implied that the marine algae should be responsible for the heavy δ^(13)C_(oil)in the Type B. The contribution of marine algae in the Central Depression may have been neglected in the past, as it is usually covered by remarkable angiosperm biomarkers.展开更多
The internal microbial diversity and small molecular metabolites of Nuodeng ham in different processing years(the first,second and third year sample)were analyzed by high-throughput sequencing technology and gas chrom...The internal microbial diversity and small molecular metabolites of Nuodeng ham in different processing years(the first,second and third year sample)were analyzed by high-throughput sequencing technology and gas chromatography-time of flight mass spectrography(GC-TOF-MS)to study the effects of microorganisms and small molecular metabolites on the quality of ham in different processing years.The results showed that the dominant bacteria phyla of Nuodeng ham in different processing years were Proteobacteria and Firmicutes,the dominant fungi phyla were Ascomycota and Basidiomycota,while Staphylococcus and Aspergillus were the dominant bacteria and fungi of Nuodeng ham,respectively.Totally,252 kinds of small molecular metabolites were identified from Nuodeng ham in different processing years,and 12 different metabolites were screened through multivariate statistical analysis.Further metabolic pathway analysis showed that 23 metabolic pathways were related to ham fermentation,of which 8 metabolic pathways had significant effects on ham fermentation(Impact>0.01,P<0.05).The content of L-proline,phenyllactic acid,L-lysine,carnosine,taurine,D-proline,betaine and creatine were significantly positively correlated with the relative abundance of Staphylococcus and Serratia,but negatively correlated with the relative abundance of Halomonas,Aspergillus and Yamadazyma.展开更多
A GC-MS method for the determination of 27 organochlorine pesticides and 15 Pyrethroid pesticides in animal food is established.The method was based on Gel Permeation chromatography combined with solid-phase extractio...A GC-MS method for the determination of 27 organochlorine pesticides and 15 Pyrethroid pesticides in animal food is established.The method was based on Gel Permeation chromatography combined with solid-phase extraction for sample preparation.Rapid qualitative and quantitative analyses was carried out by gas chromatography-mass spectrometry under the selective-ion monitoring mode.The experimental results showed that the correlation coefficients were better than 0.99,the recoveries for spiked standards were 70%-104%,the relative standard deviations were 2.1%-15.9%.展开更多
Gas chromatography-mass spectrometry (GC-MS) method has been developed for the simultaneous determination of monoethanolamine,diethanolamine,triethanolamine in cosmetics.The detected materials were extracted with etha...Gas chromatography-mass spectrometry (GC-MS) method has been developed for the simultaneous determination of monoethanolamine,diethanolamine,triethanolamine in cosmetics.The detected materials were extracted with ethanol by ultrasonic, then were analyzed by GC-FID and GC-MSD.The relative standard deviations (RSD) were 0.76%-3.43%,and recoveries were 85.8%-106.0%. The limit of detection was 0.05%.展开更多
In this paper,the Illilium verum Hook.f.grow at mountain of Dayao of Jinxiu in Guangxi,Volatile oil was extracted by soxhet method and steam distillation.All the volatile oil was analyzed by GC-MS,the result show the ...In this paper,the Illilium verum Hook.f.grow at mountain of Dayao of Jinxiu in Guangxi,Volatile oil was extracted by soxhet method and steam distillation.All the volatile oil was analyzed by GC-MS,the result show the ingredients and rate of product were change greatly,The major chemical constituents were trans-anethole,estragole and anisaldehyde etc.展开更多
The metabolites and metabolic passways of nitrazepam in rat were confirmed.Wistar rats were feed a pill of nitrazepam,24 h urine reactions were collected.After β-Glucuronidase hydrolysis of the urine samples,the frac...The metabolites and metabolic passways of nitrazepam in rat were confirmed.Wistar rats were feed a pill of nitrazepam,24 h urine reactions were collected.After β-Glucuronidase hydrolysis of the urine samples,the fractions were extracted by Oasis HLB3cc solid-phase column and analyzed by gas chromatography-mass spectrometry with DB-35 MS column.7-Acetylaminonitrazepam,7-aminonitrazepam and 2-amino-5-nitrophenylphenylmethanone were identified as nitrazepam metabolites.The results suggested that two metabolic passways for nitrazepam may be operative in rat.The first passway leads to the corresponding 7-aminonimetazepam in which the amino group is subsequently acetylated.The second passway is open the parent compounds rings to 2-amino-5-nitrophenylphenylmethanone.Nitrazepam was metabolized quickly in rats and 7-acetylaminonitrazepam were the main metabolites in urine.展开更多
The emulsible explosives and its post-blast residues were analyzed by gas chromatography-mass spectrometry(GC-MS).A sensitive analysis method has been established.
The volatile oil was extracted from Curcuma longa and Turmeric oleoresin by Soxhelt method with petroleum ether.All the volatile oil was analyzed of chemical component by the method of GC-MS,the relative contents of t...The volatile oil was extracted from Curcuma longa and Turmeric oleoresin by Soxhelt method with petroleum ether.All the volatile oil was analyzed of chemical component by the method of GC-MS,the relative contents of these compounds were calculated using square peaks to normalization.On the volatile oil of Curcuma longa 35 peaks were separated and 21 compounds were identified,which accounted for 89.10%,the main chemical constituents was (-)-Zingiberene(22.12%),β-Sesquiphellandrene(15.24%),α-Turmerone (11.30%),β-Turmerone (8.87%),Ar-turmerone(8.20%),but on the volatile oil of Turmeric oleoresin 32 peaks were separated,of which 21 compounds were identified,which accounted for 90.12% the main chemical constituents was (-)-Zingiberene(23.92%),β-Sesquiphellandrene(15.73%),Ar-turmerone(12.89%),β-Turmerone(10.85%).展开更多
The chemical detection of gasoline traces in fire debris is a challenge requiring highly sensitive,hyphenated analytical systems.The gas chromatography-mass spectrometry is suitable for the task.In this study,GC-MS we...The chemical detection of gasoline traces in fire debris is a challenge requiring highly sensitive,hyphenated analytical systems.The gas chromatography-mass spectrometry is suitable for the task.In this study,GC-MS were optimized to identify gasoline in simulated fire.And it was successful to apply this method to detect the gasoline in fire debris.展开更多
Analysis of nerve agents and their degradation products constitutes an important subject for verifying the compliance to the Chemical Weapons Convention(CWC).In environmental water,the relevant degradation products of...Analysis of nerve agents and their degradation products constitutes an important subject for verifying the compliance to the Chemical Weapons Convention(CWC).In environmental water,the relevant degradation products of nerve agents are usually present at low concentration levels and mixed with a large amount of interferents.In this paper,six different kinds of solid-phase bulk sorbents were respectively investigated to improve the SPE efficiency for nerve agents degradation products from stimulant water samples,in which a large amount of background interferents were spiked.Results showed that the strong anion-exchange sorbent could selectively extract the spiking six target compounds from the matrices and showed a high recovery.展开更多
基金This work was supported by the National Natural Science Foundation of China(No.51673012)National Key Research and Development Plan Fund(No.2017YFB0306901,2016YFF0203703-03)the Beijing Technology and Business University Youth Scholar Funds(No.PXM2019_014213_000007).
文摘Nowadays,natural rubber(NR)is an indispensable material for industrial production and peoples’daily utilization.The root of Taraxacum kok-saghyz(TKS)contains a large amount of NR,which is potentially to be an alternative rubber source of conventional Hevea brasiliensis(HB).In order to find a convenient,fast and green method for qualitative and quantitative analysis of NR in TKS,a pyrolysis gas chromatography-mass spectrometric(Py-GCMS)method was developed accordingly.The results indicated that the main products of TKS rubber after pyrolysis were isoprene and limonene,respectively,and the limit of detection(LOD)of TKS rubber was 2.603 mg/g.The ratios of NR mass fractions in TKSs by Py-GC-MS ranged from 1.20%±0.20%to 8.61%±0.28%.The developed method has been used for determination of actual TKS samples and can be further applied to the field test for rapid breeding and large-scale cultivation of TKS thereof.
基金supported by the Research and Development of Ecological Control Mechanisms and Application Techniques for Forest Pest and Disease in the North and South Mountains of Lhasa(No.XZ202301ZY0019N)Construction and Comprehensive Service Cap ability Enhancement of Plateau Characteristic Agricultural and Animal Husbandry Science and Technology Small Courtyard(XK202403)。
文摘This study examined the EAG(Electroantennogram)responses of Stilpnotia candida to a mix of host plant volatiles and to provide a foundation for the development of plant-derived attractants.During the peak period of adult eclosion,gas chromatography–mass spectrometry analyzed and identified the volatiles emitted by Populus×beijingensis found in Xizang.Based on the preliminary EAG experiments and the GC‒MS results,a blending scheme was developed.EAG and Y-tube-olfactometry were employed to measure the electrophysiological and behavioural responses of unmated males and females 24 h after eclosion 10 blends of volatiles derived from five host plants.The GC–MS analysis revealed 22 volatile compounds from Populus×beijingensis leaves,composed of esters,hydrocarbons,terpenoids,alcohols,phenols,and ether.The results indicated that all 10 blending schemes produced EAG responses in mature S.candida.The concentration thresholds were between 1 and 10μg·μL^(-1),above the optimal concentration,and a corresponding decrease in EAG was observed.According to intergroup comparisons,mature S.candida had more pronounced EAG responses.Under different concentrations,there were significant differences in the EAG from male and female S.candida to each blending scheme.Behavioural response tests indicated that schemes 2,7,and 8 exhibited significantly greater attractiveness to adult S.candida.The combined results from the EAG and behavioral response experiments demonstrated that unmated male and female adult S.candida have varying degrees of sensitivity to the volatile compounds from the 10 blending schemes specific to Xizangan Populus×beijingensis.Schemes 2,7,and 8 showed robust EAG responses and attractive behavioural responses to both male and female adult S.candida.
基金supported by the National Natural Science Foundation of China (Grant No. 42302189)。
文摘Molecular biomarker and whole oil carbon isotope(δ^(13)C_(oil)) analyses were conducted on eleven typical crude oils from the Qiongdongnan Basin to investigate their biological sources and depositional environments. Saturated hydrocarbon biomarkers in most samples are characterized by angiosperm-derived compounds, with aromatic compounds dominated by the naphthalene, phenanthrene, biphenyl, and fluorene series. The related source rocks of these oils were mainly deposited under oxic condition, but a subanoxic-suboxic and enclosed water column condition in the Central Depression during Oligocene.The identification of simonellite and related compounds in the aromatic fractions provides reliable evidence for the input of coniferous gymnosperms. Cadalene may also have a potential association with gymnosperms since it shows a strong positive correlation with simonellite. Evidence from density, nalkanes, short-chain alkylbenzenes and secondary brine inclusions indicates that the unique crude oil B13-1 may have suffered from thermal alteration. These crude oils(excluding B13-1) can be classified into four types based on the δ^(13)C_(oil)values and molecular biomarkers. Type A oil(solely S34-3) is characterized by non-angiosperm plants, with minor dinoflagellates and increasing contribution from conifer gymnosperms than others. Type B oils(L17-2, L18-1, L25-1, and L25-1W) show heavy δ^(13)C_(oil)(-24 ‰to-25 ‰) and mixed contributions from both angiosperms and marine algae, with the marine algae contribution increasing. Type C oils(L13-2 and B21-1) share similar biological sources with Type B, but the moderately δ^(13)C_(oil)(-25‰ to-26‰) and high level of terrestrial biomarkers suggesting a predominant contribution of angiosperms. Type D oils(Y13-1a, Y13-1b, and Y13-4) possess the lightestδ^(13)C_(oil)(mainly below-26‰) and are primarily derived from angiosperms, with mangrove vegetation playing an important role. Spearman correlation analysis among 14 source biomarker parameters withδ^(13)C_(oil)and geological setting of related source rocks implied that the marine algae should be responsible for the heavy δ^(13)C_(oil)in the Type B. The contribution of marine algae in the Central Depression may have been neglected in the past, as it is usually covered by remarkable angiosperm biomarkers.
基金supported by Major Science and Technology Projects of Yunnan Science and Technology Plan(2019ZG003)Yunnan Young and Middle-aged Academic and Technical Leader Reserve Talent Project(202105AC160068)。
文摘The internal microbial diversity and small molecular metabolites of Nuodeng ham in different processing years(the first,second and third year sample)were analyzed by high-throughput sequencing technology and gas chromatography-time of flight mass spectrography(GC-TOF-MS)to study the effects of microorganisms and small molecular metabolites on the quality of ham in different processing years.The results showed that the dominant bacteria phyla of Nuodeng ham in different processing years were Proteobacteria and Firmicutes,the dominant fungi phyla were Ascomycota and Basidiomycota,while Staphylococcus and Aspergillus were the dominant bacteria and fungi of Nuodeng ham,respectively.Totally,252 kinds of small molecular metabolites were identified from Nuodeng ham in different processing years,and 12 different metabolites were screened through multivariate statistical analysis.Further metabolic pathway analysis showed that 23 metabolic pathways were related to ham fermentation,of which 8 metabolic pathways had significant effects on ham fermentation(Impact>0.01,P<0.05).The content of L-proline,phenyllactic acid,L-lysine,carnosine,taurine,D-proline,betaine and creatine were significantly positively correlated with the relative abundance of Staphylococcus and Serratia,but negatively correlated with the relative abundance of Halomonas,Aspergillus and Yamadazyma.
文摘A GC-MS method for the determination of 27 organochlorine pesticides and 15 Pyrethroid pesticides in animal food is established.The method was based on Gel Permeation chromatography combined with solid-phase extraction for sample preparation.Rapid qualitative and quantitative analyses was carried out by gas chromatography-mass spectrometry under the selective-ion monitoring mode.The experimental results showed that the correlation coefficients were better than 0.99,the recoveries for spiked standards were 70%-104%,the relative standard deviations were 2.1%-15.9%.
文摘Gas chromatography-mass spectrometry (GC-MS) method has been developed for the simultaneous determination of monoethanolamine,diethanolamine,triethanolamine in cosmetics.The detected materials were extracted with ethanol by ultrasonic, then were analyzed by GC-FID and GC-MSD.The relative standard deviations (RSD) were 0.76%-3.43%,and recoveries were 85.8%-106.0%. The limit of detection was 0.05%.
文摘In this paper,the Illilium verum Hook.f.grow at mountain of Dayao of Jinxiu in Guangxi,Volatile oil was extracted by soxhet method and steam distillation.All the volatile oil was analyzed by GC-MS,the result show the ingredients and rate of product were change greatly,The major chemical constituents were trans-anethole,estragole and anisaldehyde etc.
文摘The metabolites and metabolic passways of nitrazepam in rat were confirmed.Wistar rats were feed a pill of nitrazepam,24 h urine reactions were collected.After β-Glucuronidase hydrolysis of the urine samples,the fractions were extracted by Oasis HLB3cc solid-phase column and analyzed by gas chromatography-mass spectrometry with DB-35 MS column.7-Acetylaminonitrazepam,7-aminonitrazepam and 2-amino-5-nitrophenylphenylmethanone were identified as nitrazepam metabolites.The results suggested that two metabolic passways for nitrazepam may be operative in rat.The first passway leads to the corresponding 7-aminonimetazepam in which the amino group is subsequently acetylated.The second passway is open the parent compounds rings to 2-amino-5-nitrophenylphenylmethanone.Nitrazepam was metabolized quickly in rats and 7-acetylaminonitrazepam were the main metabolites in urine.
文摘The emulsible explosives and its post-blast residues were analyzed by gas chromatography-mass spectrometry(GC-MS).A sensitive analysis method has been established.
文摘The volatile oil was extracted from Curcuma longa and Turmeric oleoresin by Soxhelt method with petroleum ether.All the volatile oil was analyzed of chemical component by the method of GC-MS,the relative contents of these compounds were calculated using square peaks to normalization.On the volatile oil of Curcuma longa 35 peaks were separated and 21 compounds were identified,which accounted for 89.10%,the main chemical constituents was (-)-Zingiberene(22.12%),β-Sesquiphellandrene(15.24%),α-Turmerone (11.30%),β-Turmerone (8.87%),Ar-turmerone(8.20%),but on the volatile oil of Turmeric oleoresin 32 peaks were separated,of which 21 compounds were identified,which accounted for 90.12% the main chemical constituents was (-)-Zingiberene(23.92%),β-Sesquiphellandrene(15.73%),Ar-turmerone(12.89%),β-Turmerone(10.85%).
文摘The chemical detection of gasoline traces in fire debris is a challenge requiring highly sensitive,hyphenated analytical systems.The gas chromatography-mass spectrometry is suitable for the task.In this study,GC-MS were optimized to identify gasoline in simulated fire.And it was successful to apply this method to detect the gasoline in fire debris.
文摘Analysis of nerve agents and their degradation products constitutes an important subject for verifying the compliance to the Chemical Weapons Convention(CWC).In environmental water,the relevant degradation products of nerve agents are usually present at low concentration levels and mixed with a large amount of interferents.In this paper,six different kinds of solid-phase bulk sorbents were respectively investigated to improve the SPE efficiency for nerve agents degradation products from stimulant water samples,in which a large amount of background interferents were spiked.Results showed that the strong anion-exchange sorbent could selectively extract the spiking six target compounds from the matrices and showed a high recovery.