To establish a rapid and effective method for analysis and identification of the alkaloids from Ranunculus japoni- cus Thunb by ultra-performance liquid chromatogaraphy with quadruple-time-of-flight mass spectrometry ...To establish a rapid and effective method for analysis and identification of the alkaloids from Ranunculus japoni- cus Thunb by ultra-performance liquid chromatogaraphy with quadruple-time-of-flight mass spectrometry （UPLC/Q-TOF- MS） and discuss their fragmentation regularity, the UPLC/Q-TOF-MS was used to identify the alkaloids from Ranunculus japonicus Thunb by their MS data, tandem characteristic fragment ions and standards. In the end, 12 alkaloids were identi- fied from Ranunculus japonicus for the first time, and their fragmentation regularity was discussed. Thus, a rapid and effec- tive analysis and identification method for the alkaloids from Ranunculus japonicus by UPLC/Q-TOF-MS is established.展开更多
The pilot performance of the combined GAC-MF membrane process for drinking water advanced treatment was described. In the process of GAC adsorption, under the conditions of 20 min HRT and 6 m/h filtration rate, the re...The pilot performance of the combined GAC-MF membrane process for drinking water advanced treatment was described. In the process of GAC adsorption, under the conditions of 20 min HRT and 6 m/h filtration rate, the removal efficiencies of UV_(254) and trichloromethane could reach 40% and 50% respectively and the UV_(254) and trichloromethane in system effluent was less than 0.015 cm^(-1) and 5μg/L respectively. In the post MF membrane process, MF membrane effectively retained the particles and bacteria in raw water. The effluent turbidity was less than 0.2 NTU and no bacteria were detected at all in permeate. A computer-controlled system was employed to control this system. The membrane operating parameters of backwash interval, duration and flux were studied. The backwash interval of 10-min, 20-min and 60-min was researched respectively, and the variation of trans-membrane pressure was also analyzed. Consequently short backwash interval was recommended under the same water consume.展开更多
Objective To identify the compounds withα-glucosidase inhibitory activity from Clerodendrum bungei Steud(Chou Mu Dan,臭牡丹)using HPLC-ESI-QTOF-MS/MS.Methods The ethanol extracts of Clerodendrum bungei Steud(Chou Mu ...Objective To identify the compounds withα-glucosidase inhibitory activity from Clerodendrum bungei Steud(Chou Mu Dan,臭牡丹)using HPLC-ESI-QTOF-MS/MS.Methods The ethanol extracts of Clerodendrum bungei Steud(Chou Mu Dan,臭牡丹)were partitioned with petroleum ether,ethyl acetate,n-butanol,and water.The assay forα-glucosidase inhibitory activity revealed strongα-glucosidase inhibitory activity in the ethyl acetate fraction,and the bioactive compounds present in this fraction were identified by the HPLCESI-QTOF-MS/MS method.Results A total of 29 compounds were determined,among the identified bioactive components;these included 12 phenylethanoid glycosides(compounds 5,6,17,20-22,24),7 flavonoids(compounds 10,19,23,25-28),5 phenolic acids(compounds 2-4,7,9),and 5 other compounds.Compounds 2-4,7,9-10,12-13,15,19,and 26,with a potentialα-glucosidase inhibitory activity,have been reported previously.Conclusions Our results show that the methodology used in this study is feasible,credible,and rapid in identifying known compounds and also for characterizing new natural glucosidase inhibitory candidates from Clerodendrum bungei Steud(Chou Mu Dan,臭牡丹).展开更多
This paper makes researches on multiple independently reentry vehicle （MIRV） ballistic missile interception. It breaks through traditional intercepting methods of missiles and combines comba- ting time characteristi...This paper makes researches on multiple independently reentry vehicle （MIRV） ballistic missile interception. It breaks through traditional intercepting methods of missiles and combines comba- ting time characteristics of MIRV missiles with the principle of computer process schedule. In this paper, a way of firstly intercepting the target missile with higher threaten grade is proposed. This method determines the threaten grade of the attacking target according to computer process schedu- ling algorithms, then appljed a proportional navigation guidance law to intercept target missiles in priority so that it achieves the effect of less damage. The simulation results indicate that it is effective to use the proportional navigation guidance law based on the process scheduling to intercept target missile. It possesses referential value in modem weapon combats.展开更多
文摘To establish a rapid and effective method for analysis and identification of the alkaloids from Ranunculus japoni- cus Thunb by ultra-performance liquid chromatogaraphy with quadruple-time-of-flight mass spectrometry （UPLC/Q-TOF- MS） and discuss their fragmentation regularity, the UPLC/Q-TOF-MS was used to identify the alkaloids from Ranunculus japonicus Thunb by their MS data, tandem characteristic fragment ions and standards. In the end, 12 alkaloids were identi- fied from Ranunculus japonicus for the first time, and their fragmentation regularity was discussed. Thus, a rapid and effec- tive analysis and identification method for the alkaloids from Ranunculus japonicus by UPLC/Q-TOF-MS is established.
基金Sponsored by Fok Ying Tung Education Foundation (No. 94004)
文摘The pilot performance of the combined GAC-MF membrane process for drinking water advanced treatment was described. In the process of GAC adsorption, under the conditions of 20 min HRT and 6 m/h filtration rate, the removal efficiencies of UV_(254) and trichloromethane could reach 40% and 50% respectively and the UV_(254) and trichloromethane in system effluent was less than 0.015 cm^(-1) and 5μg/L respectively. In the post MF membrane process, MF membrane effectively retained the particles and bacteria in raw water. The effluent turbidity was less than 0.2 NTU and no bacteria were detected at all in permeate. A computer-controlled system was employed to control this system. The membrane operating parameters of backwash interval, duration and flux were studied. The backwash interval of 10-min, 20-min and 60-min was researched respectively, and the variation of trans-membrane pressure was also analyzed. Consequently short backwash interval was recommended under the same water consume.
基金the funding support from the China National Natural Science Foundation Funding Project(NO.81503452)Natural Science Foundation of Hunan Province,China(No.14JJ4066)
文摘Objective To identify the compounds withα-glucosidase inhibitory activity from Clerodendrum bungei Steud(Chou Mu Dan,臭牡丹)using HPLC-ESI-QTOF-MS/MS.Methods The ethanol extracts of Clerodendrum bungei Steud(Chou Mu Dan,臭牡丹)were partitioned with petroleum ether,ethyl acetate,n-butanol,and water.The assay forα-glucosidase inhibitory activity revealed strongα-glucosidase inhibitory activity in the ethyl acetate fraction,and the bioactive compounds present in this fraction were identified by the HPLCESI-QTOF-MS/MS method.Results A total of 29 compounds were determined,among the identified bioactive components;these included 12 phenylethanoid glycosides(compounds 5,6,17,20-22,24),7 flavonoids(compounds 10,19,23,25-28),5 phenolic acids(compounds 2-4,7,9),and 5 other compounds.Compounds 2-4,7,9-10,12-13,15,19,and 26,with a potentialα-glucosidase inhibitory activity,have been reported previously.Conclusions Our results show that the methodology used in this study is feasible,credible,and rapid in identifying known compounds and also for characterizing new natural glucosidase inhibitory candidates from Clerodendrum bungei Steud(Chou Mu Dan,臭牡丹).
文摘This paper makes researches on multiple independently reentry vehicle （MIRV） ballistic missile interception. It breaks through traditional intercepting methods of missiles and combines comba- ting time characteristics of MIRV missiles with the principle of computer process schedule. In this paper, a way of firstly intercepting the target missile with higher threaten grade is proposed. This method determines the threaten grade of the attacking target according to computer process schedu- ling algorithms, then appljed a proportional navigation guidance law to intercept target missiles in priority so that it achieves the effect of less damage. The simulation results indicate that it is effective to use the proportional navigation guidance law based on the process scheduling to intercept target missile. It possesses referential value in modem weapon combats.
