In the present paper is reported the method for the isolation and extraction of total flavonoids of Epimedium Koreanum Nakai by means of supercritical fluid extraction(SFE). By examining pressure, temperature, amounts...In the present paper is reported the method for the isolation and extraction of total flavonoids of Epimedium Koreanum Nakai by means of supercritical fluid extraction(SFE). By examining pressure, temperature, amounts of modifier and extraction time, the optimized condition of SFE is confirmed as 30 MPa and 60 ℃, with 70% ethanol as the modifier. The samples were statically extracted for 30 min, followed by dynamic extraction for 120 min at a flow rate of 6 mL/min. The quantitative analysis of total flavonoids was performed by UV-Vis spectrophotometry. Compared with the conventional method, the SFE method is more efficient, more rapid and more friendly environmentally.展开更多
The adsorption method based on solid adsorbents is one of feasible ways to capture and store CO2. Using the ion exchange method, different zeolites Na KA varying in K+content were produced. The adsorption isotherms a...The adsorption method based on solid adsorbents is one of feasible ways to capture and store CO2. Using the ion exchange method, different zeolites Na KA varying in K+content were produced. The adsorption isotherms and kinetic uptakes were measured. The experimental results show that the optimal NaKA could adsorb significant quantities of CO2 and little N2. On the zeolite Na KA with 14.7 at.% K+, the adsorption capacity for pure CO2 is over 3.10 mmol g^-1 and the CO2–N2 selectivity is about 149 at ambient pressure and temperature. The kinetic CO2–N2 selectivity could also achieved 200 within 3 min according to the uptake data. To demonstrate the separation effectiveness, breakthrough curves of pure components and binary mixtures were investigated experimentally and theoretically in a fixed bed. It is found that the breakthrough points of CO2 and N2 are almost at the same time under the atmospheric pressure at 348 K with the raw gas composition CO2/N2(20:80, v/v). If the pressure has been increased higher than 0.1 MPa, CO2 would break through the bed much slower than N2. Therefore, the pressure may become the limiting factor for the separation performance of zeolites NaKA.展开更多
AIM: To study the effect of rabeprazole (RAB) on nocturnal acid breakthrough (NAB) and nocturnal alkaline amplitude (NAKA) and to compare it with omeprazole (OME) and pantoprazole (PAN).METHODS: By an open comparative...AIM: To study the effect of rabeprazole (RAB) on nocturnal acid breakthrough (NAB) and nocturnal alkaline amplitude (NAKA) and to compare it with omeprazole (OME) and pantoprazole (PAN).METHODS: By an open comparative study, forty patients with active peptic ulcer were randomly assigned to receive one of the three PPIs (proton pump inhibitor) with a single oral dose. They were divided into RAB group (10 mg), OME group(20 mg) and PAN group (40 mg). Twenty healthy volunteers were enrolled to the control group (without taking any drug). Intragastric pH monitoring was then performed 1 hour before and 24 hours after the dose was given.RESULTS: No clinically undesirable signs and symptoms possibly attributed to the administration of RAB or OME and PAN were recognizable throughout the study period. All subjects completed the study according to the protocol. All data were processed by a computer using the Student ttest or t' test followed by an analysis of covariance. P<0.05 was considered to have statistical significance. The intragastric pH of NAB was significantly higher in RAB group (1.84±0.55) than in either OME group (1.15±0.31) or PAN group (1.10±0.30) (both P<0.01). RAB produced a longer sustaining time (4.65±1.22 h) on NAKA than OME (3.22±1.89 h) (P<0.05),PAN (3.15±1.92 h) (P<0.05), and the sustaining time of NAKA in RAB group was longer than that in the healthy control group (P<0.01) too. In addition, RAB produced a much higher pH on NAKA (6.41±0.45) in comparison with PAN (6.01±0.92) (P<0.05).CONCLUSION: A single oral dose of 10 mg RAB may increase the pH of NAB and shorten the sustaining time of NAB, and it may increase the pH of NAKA as well as prolong the sustaining time of NAKA.展开更多
基金the Natural Science and Technology Foundation of Jilin Province(No.2 0 0 2 0 6 37- 1)
文摘In the present paper is reported the method for the isolation and extraction of total flavonoids of Epimedium Koreanum Nakai by means of supercritical fluid extraction(SFE). By examining pressure, temperature, amounts of modifier and extraction time, the optimized condition of SFE is confirmed as 30 MPa and 60 ℃, with 70% ethanol as the modifier. The samples were statically extracted for 30 min, followed by dynamic extraction for 120 min at a flow rate of 6 mL/min. The quantitative analysis of total flavonoids was performed by UV-Vis spectrophotometry. Compared with the conventional method, the SFE method is more efficient, more rapid and more friendly environmentally.
文摘The adsorption method based on solid adsorbents is one of feasible ways to capture and store CO2. Using the ion exchange method, different zeolites Na KA varying in K+content were produced. The adsorption isotherms and kinetic uptakes were measured. The experimental results show that the optimal NaKA could adsorb significant quantities of CO2 and little N2. On the zeolite Na KA with 14.7 at.% K+, the adsorption capacity for pure CO2 is over 3.10 mmol g^-1 and the CO2–N2 selectivity is about 149 at ambient pressure and temperature. The kinetic CO2–N2 selectivity could also achieved 200 within 3 min according to the uptake data. To demonstrate the separation effectiveness, breakthrough curves of pure components and binary mixtures were investigated experimentally and theoretically in a fixed bed. It is found that the breakthrough points of CO2 and N2 are almost at the same time under the atmospheric pressure at 348 K with the raw gas composition CO2/N2(20:80, v/v). If the pressure has been increased higher than 0.1 MPa, CO2 would break through the bed much slower than N2. Therefore, the pressure may become the limiting factor for the separation performance of zeolites NaKA.
文摘AIM: To study the effect of rabeprazole (RAB) on nocturnal acid breakthrough (NAB) and nocturnal alkaline amplitude (NAKA) and to compare it with omeprazole (OME) and pantoprazole (PAN).METHODS: By an open comparative study, forty patients with active peptic ulcer were randomly assigned to receive one of the three PPIs (proton pump inhibitor) with a single oral dose. They were divided into RAB group (10 mg), OME group(20 mg) and PAN group (40 mg). Twenty healthy volunteers were enrolled to the control group (without taking any drug). Intragastric pH monitoring was then performed 1 hour before and 24 hours after the dose was given.RESULTS: No clinically undesirable signs and symptoms possibly attributed to the administration of RAB or OME and PAN were recognizable throughout the study period. All subjects completed the study according to the protocol. All data were processed by a computer using the Student ttest or t' test followed by an analysis of covariance. P<0.05 was considered to have statistical significance. The intragastric pH of NAB was significantly higher in RAB group (1.84±0.55) than in either OME group (1.15±0.31) or PAN group (1.10±0.30) (both P<0.01). RAB produced a longer sustaining time (4.65±1.22 h) on NAKA than OME (3.22±1.89 h) (P<0.05),PAN (3.15±1.92 h) (P<0.05), and the sustaining time of NAKA in RAB group was longer than that in the healthy control group (P<0.01) too. In addition, RAB produced a much higher pH on NAKA (6.41±0.45) in comparison with PAN (6.01±0.92) (P<0.05).CONCLUSION: A single oral dose of 10 mg RAB may increase the pH of NAB and shorten the sustaining time of NAB, and it may increase the pH of NAKA as well as prolong the sustaining time of NAKA.