Comprehensive two-dimensional liquid chromatography platform(LC×LC)coupled with quadrupole time-of-flight(QTOF)mass spectrometry(MS)is developed to separate,identify and relatively determine the chemical constitu...Comprehensive two-dimensional liquid chromatography platform(LC×LC)coupled with quadrupole time-of-flight(QTOF)mass spectrometry(MS)is developed to separate,identify and relatively determine the chemical constituents of two types of tripterygium glycosides tablets(TGT).The types and relative contents of the constituents discovered in two kinds of TGT tablets were subsequently compared.C8andC18 column were used for the separation of the first展开更多
We aimed to establish for the rapid detection of morphine,O6‑monoacetylmorphine,heroin,codeine,cocaine,methamphetamine,ketamine,methadone,and dolantin in human blood and urine by direct analysis in real‑time coupled w...We aimed to establish for the rapid detection of morphine,O6‑monoacetylmorphine,heroin,codeine,cocaine,methamphetamine,ketamine,methadone,and dolantin in human blood and urine by direct analysis in real‑time coupled with tandem mass spectrometry(DART‑MS/MS).These samples were extracted by acetonitrile‑methanol(V/V=4:1),using DART 12 Dip‑it automatic sampling system.They were injected at 400℃,and analyzed by positive ion and multiple reaction monitoring mode.The detection limits of morphine,O6‑Monoacetylmorphine,heroin,codeine,cocaine,methamphetamine,ketamine,methadone,and dolantin were 100,50,50,100,20,20,10,1,and 0.01 ng/mL,respectively.The practical cases contained methamphetamine,codeine,cocaine,and O6‑monoacetylmorphine were detected accurately and rapidly.The method has the advantages of high sensitivity and good accuracy.The sample processing is simple and can be analyzed in a short time.This method is suitable for the analysis of morphine,O6‑monoacetylmorphine,heroin,codeine,cocaine,methamphetamine,ketamine,methadone,and dolantin in some practical cases.展开更多
The oxidation of lignite and bituminous coal samples modified by 5 wt%(in terms of dry salt)addition of copper salts Cu(NO_(3))_(2),CuSO_(4),and Cu(CH_(3)COO)_(2) was studied.The samples’reactivity was studied by the...The oxidation of lignite and bituminous coal samples modified by 5 wt%(in terms of dry salt)addition of copper salts Cu(NO_(3))_(2),CuSO_(4),and Cu(CH_(3)COO)_(2) was studied.The samples’reactivity was studied by thermogravimetry within a temperature range of 45–600℃ at a heating rate of 2.5℃/min in an oxidizing environment.The introduction of activating additives has resulted in a significant decrease in the temperature of intense oxidation onset(ΔT_(i)=20/94℃),in a reduction in the sample residence time in the volatile matter release region(Δt_(e)=2/22 min)and the total duration of the coal combustible mass oxidation(Δt_(f)=8/14 min).The Friedman method was used to calculate the activation energy values for the oxidation process of the modified samples.The maximum change in activation energy values was observed for the bituminous coal sample.The possible mechanism behind the action of the copper-salt additives,which activate the oxidation of lignite and bituminous coal,is discussed.According to the data of mass spectrometric analysis,the concentration of NOx in the reaction products decreases as the temperature of the activated oxidation process is shifted towards the low-temperature region.展开更多
文摘Comprehensive two-dimensional liquid chromatography platform(LC×LC)coupled with quadrupole time-of-flight(QTOF)mass spectrometry(MS)is developed to separate,identify and relatively determine the chemical constituents of two types of tripterygium glycosides tablets(TGT).The types and relative contents of the constituents discovered in two kinds of TGT tablets were subsequently compared.C8andC18 column were used for the separation of the first
基金This research was supported by the Project for Strengthening the Police Force with Science and Technology(project number 2018GABJC29).
文摘We aimed to establish for the rapid detection of morphine,O6‑monoacetylmorphine,heroin,codeine,cocaine,methamphetamine,ketamine,methadone,and dolantin in human blood and urine by direct analysis in real‑time coupled with tandem mass spectrometry(DART‑MS/MS).These samples were extracted by acetonitrile‑methanol(V/V=4:1),using DART 12 Dip‑it automatic sampling system.They were injected at 400℃,and analyzed by positive ion and multiple reaction monitoring mode.The detection limits of morphine,O6‑Monoacetylmorphine,heroin,codeine,cocaine,methamphetamine,ketamine,methadone,and dolantin were 100,50,50,100,20,20,10,1,and 0.01 ng/mL,respectively.The practical cases contained methamphetamine,codeine,cocaine,and O6‑monoacetylmorphine were detected accurately and rapidly.The method has the advantages of high sensitivity and good accuracy.The sample processing is simple and can be analyzed in a short time.This method is suitable for the analysis of morphine,O6‑monoacetylmorphine,heroin,codeine,cocaine,methamphetamine,ketamine,methadone,and dolantin in some practical cases.
基金This work was supported by the Ministry of Science and Higher Education of the Russian Federation(projects No.FSWW-2020-0022 and AAAA-A17-117041710086-6).
文摘The oxidation of lignite and bituminous coal samples modified by 5 wt%(in terms of dry salt)addition of copper salts Cu(NO_(3))_(2),CuSO_(4),and Cu(CH_(3)COO)_(2) was studied.The samples’reactivity was studied by thermogravimetry within a temperature range of 45–600℃ at a heating rate of 2.5℃/min in an oxidizing environment.The introduction of activating additives has resulted in a significant decrease in the temperature of intense oxidation onset(ΔT_(i)=20/94℃),in a reduction in the sample residence time in the volatile matter release region(Δt_(e)=2/22 min)and the total duration of the coal combustible mass oxidation(Δt_(f)=8/14 min).The Friedman method was used to calculate the activation energy values for the oxidation process of the modified samples.The maximum change in activation energy values was observed for the bituminous coal sample.The possible mechanism behind the action of the copper-salt additives,which activate the oxidation of lignite and bituminous coal,is discussed.According to the data of mass spectrometric analysis,the concentration of NOx in the reaction products decreases as the temperature of the activated oxidation process is shifted towards the low-temperature region.