Objective: To study the pharmacokinetics of 20(R)-Ginsenoside Rg3 in the human body. Methods: High-performance liquid chromatography-ultraviolet detection method was used in this study. Results: The pharmacokinetics o...Objective: To study the pharmacokinetics of 20(R)-Ginsenoside Rg3 in the human body. Methods: High-performance liquid chromatography-ultraviolet detection method was used in this study. Results: The pharmacokinetics of Ginsenoside Rg3 in 14 healthy volunteers were investigated. After a single oral dose of 3.2 mg.g-1 Ginsenoside Rg3 in 8 male volunteers, the plasma concentration-time course fitted in well with a two-compartment open model, with the following pharmacokinetic parameters: Tmax 0.660.10 h, Cmax 166 ngmL-1, T1/2a 0.460.12 h, T1/2b 4.91.1 h, T1/2(Ka) 0.280.04 h, AUC0-∞ 7726 ngmL-1h, respectively. No kinetic analysis was made after an oral dose of 0.8 mg.g-1 Rg3 in other 6 volunteers because of the low concentration, but there was a good correlation between Cmax and dosage of the two groups. Conclusion: The absorption of Rg3 was rapid in the human body, and its elimination was rapid too after oral administration of Ginsenoside Rg3. The pharmacokinetic results shows that it exhibited the first-order kinetic characteristics.展开更多
The size of bubbles created in the flotation process is of great importance to the efficiency of the mineral separation achieved.Meanwhile,it is believed that frother transport between phases is perhaps the most impor...The size of bubbles created in the flotation process is of great importance to the efficiency of the mineral separation achieved.Meanwhile,it is believed that frother transport between phases is perhaps the most important reason for the interactive nature of the phenomena occurring in the bulk and froth phases in flotation,as frother adsorbed in the surface of rising bubbles is removed from the bulk phase and then released into the froth as a fraction of the bubbles burst.This causes the increased concentration in the froth compared to the bulk concentration,named as frother partitioning.Partitioning reflects the adsorption of frother on bubbles and how to influence bubble size is not known.There currently exists no such a topic aiming to link these two key parameters.To fill this vacancy,the correspondence between bubble size and frother partitioning was examined.Bubble size was measured by sampling-for-imaging(SFI)technique.Using total organic carbon(TOC)analysis to measure the frother partitioning between froth and bulk phases was determined.Measurements have shown,with no exceptions including four different frothers,higher frother concentration is in the bulk than in the froth.The results also show strong partitioning giving an increase in bubble size which implies there is a compelling relationship between these two,represented by CFroth/CBulk and D32.The CFroth/CBulkand D32 curves show similar exponential decay relationships as a function of added frother in the system,strongly suggesting that the frother concentration gradient between the bulk solution and the bubble interface is the driving force contributing to bubble size reduction.展开更多
Surface dilational rheological behavior and foam stability of starch/surfactant mixed solutions were studied at different starch concentrations and constant surfactant concentration. The results show that dilational v...Surface dilational rheological behavior and foam stability of starch/surfactant mixed solutions were studied at different starch concentrations and constant surfactant concentration. The results show that dilational viscoelasticity modulus, dilational elasticity modulus and dilational viscosity modulus increase with the concentration of starch particles. Foam stability increases with dilational viscoelasticity. Foam strength also increases with starch concentration. Starch particles play a positive effect on foam stability and dilational viscoelasticity and the effect becomes more significant as drainage proceeds. Film pictures indicate that the film with 20%(by mass) starch particles is thicker than that without starch. Starch particles gather in Plateau border and resist drainage, making the foam more stable.展开更多
The aim of the study was to compare radon concentrations and effective dose equivalent in state hospitals inside the Erbil city having different periods of building. Effective doses were estimated in different floors ...The aim of the study was to compare radon concentrations and effective dose equivalent in state hospitals inside the Erbil city having different periods of building. Effective doses were estimated in different floors of the five selected hospitals by using the （CR-39） solid state nuclear track detectors with the guide of 1CRP Publication 66. The hanged dosimeters were left for about 60 days and after etching the radon concentration, annual effective dose and effective dose equivalents were calculated. Annual effective doses were estimated as 〈 1 mSv, so the results reveal the present concentrations to be below the standard values in the studied hospitals. Therefore, no healthy risks concerning the radon activities are existing in the hospital staff and patients in these hospitals.展开更多
In this study, sixteen soil and vegetable samples from Tafila district were collected and analyzed from eight locations. Measurements of specific activity of natural gamma emitter radionuclides, 23SU and 235U, in thes...In this study, sixteen soil and vegetable samples from Tafila district were collected and analyzed from eight locations. Measurements of specific activity of natural gamma emitter radionuclides, 23SU and 235U, in these samples using gamma spectrometry, with the help of Genie 2000 software. Measurements were used to calculate the soil-vegetable transfer factor, and then the external radiation dose and internal radiation dose due to radioactivity of the ingested food. The specific activity of238U and 235U in soil were found to vary from （in Bq/kg）： 26-575 and 1.4-35.5, respectively. The specific activity of 238U and 235U in vegetables were found to vary from （in Bq/kg）： 0.019 to 0.632 and 0.0013-0.0375, respectively. The calculated transfer factor of Z3SU and Z35U range from 5.9 × 10^-4to 14.6 × 10^-4 for 238U and 4.9 × 10^-4 to 16.1 × 10^-4 for 235U. External absorbed dose rates were calculated to be in the range from 12.42 to 266.00 nGy/h. The annual effective dose was found to vary from 28.94 to 619.78 μSv/y. The annual internal effective dose due to 23SU and 23SU for fresh weights ofvegetablesl were found to vary from 0.9 × 10^-3 to 35.1 × 10^-3 μSv/y for 238U and 0.61 × 10^-4 to 17.62 × 10^-4 μSv/y for 235U.展开更多
文摘Objective: To study the pharmacokinetics of 20(R)-Ginsenoside Rg3 in the human body. Methods: High-performance liquid chromatography-ultraviolet detection method was used in this study. Results: The pharmacokinetics of Ginsenoside Rg3 in 14 healthy volunteers were investigated. After a single oral dose of 3.2 mg.g-1 Ginsenoside Rg3 in 8 male volunteers, the plasma concentration-time course fitted in well with a two-compartment open model, with the following pharmacokinetic parameters: Tmax 0.660.10 h, Cmax 166 ngmL-1, T1/2a 0.460.12 h, T1/2b 4.91.1 h, T1/2(Ka) 0.280.04 h, AUC0-∞ 7726 ngmL-1h, respectively. No kinetic analysis was made after an oral dose of 0.8 mg.g-1 Rg3 in other 6 volunteers because of the low concentration, but there was a good correlation between Cmax and dosage of the two groups. Conclusion: The absorption of Rg3 was rapid in the human body, and its elimination was rapid too after oral administration of Ginsenoside Rg3. The pharmacokinetic results shows that it exhibited the first-order kinetic characteristics.
基金Project supported by the Collaborative Research and Development Program of Natural Sciences and Engineering Research Council of Canada
文摘The size of bubbles created in the flotation process is of great importance to the efficiency of the mineral separation achieved.Meanwhile,it is believed that frother transport between phases is perhaps the most important reason for the interactive nature of the phenomena occurring in the bulk and froth phases in flotation,as frother adsorbed in the surface of rising bubbles is removed from the bulk phase and then released into the froth as a fraction of the bubbles burst.This causes the increased concentration in the froth compared to the bulk concentration,named as frother partitioning.Partitioning reflects the adsorption of frother on bubbles and how to influence bubble size is not known.There currently exists no such a topic aiming to link these two key parameters.To fill this vacancy,the correspondence between bubble size and frother partitioning was examined.Bubble size was measured by sampling-for-imaging(SFI)technique.Using total organic carbon(TOC)analysis to measure the frother partitioning between froth and bulk phases was determined.Measurements have shown,with no exceptions including four different frothers,higher frother concentration is in the bulk than in the froth.The results also show strong partitioning giving an increase in bubble size which implies there is a compelling relationship between these two,represented by CFroth/CBulk and D32.The CFroth/CBulkand D32 curves show similar exponential decay relationships as a function of added frother in the system,strongly suggesting that the frother concentration gradient between the bulk solution and the bubble interface is the driving force contributing to bubble size reduction.
基金Supported by the Petro China Company Limited Project(2011B-1303)the National Natural Science Foundation of China(21276022)CNPC Innovation Foundation(2012D-5006-0208)
文摘Surface dilational rheological behavior and foam stability of starch/surfactant mixed solutions were studied at different starch concentrations and constant surfactant concentration. The results show that dilational viscoelasticity modulus, dilational elasticity modulus and dilational viscosity modulus increase with the concentration of starch particles. Foam stability increases with dilational viscoelasticity. Foam strength also increases with starch concentration. Starch particles play a positive effect on foam stability and dilational viscoelasticity and the effect becomes more significant as drainage proceeds. Film pictures indicate that the film with 20%(by mass) starch particles is thicker than that without starch. Starch particles gather in Plateau border and resist drainage, making the foam more stable.
文摘The aim of the study was to compare radon concentrations and effective dose equivalent in state hospitals inside the Erbil city having different periods of building. Effective doses were estimated in different floors of the five selected hospitals by using the （CR-39） solid state nuclear track detectors with the guide of 1CRP Publication 66. The hanged dosimeters were left for about 60 days and after etching the radon concentration, annual effective dose and effective dose equivalents were calculated. Annual effective doses were estimated as 〈 1 mSv, so the results reveal the present concentrations to be below the standard values in the studied hospitals. Therefore, no healthy risks concerning the radon activities are existing in the hospital staff and patients in these hospitals.
文摘In this study, sixteen soil and vegetable samples from Tafila district were collected and analyzed from eight locations. Measurements of specific activity of natural gamma emitter radionuclides, 23SU and 235U, in these samples using gamma spectrometry, with the help of Genie 2000 software. Measurements were used to calculate the soil-vegetable transfer factor, and then the external radiation dose and internal radiation dose due to radioactivity of the ingested food. The specific activity of238U and 235U in soil were found to vary from （in Bq/kg）： 26-575 and 1.4-35.5, respectively. The specific activity of 238U and 235U in vegetables were found to vary from （in Bq/kg）： 0.019 to 0.632 and 0.0013-0.0375, respectively. The calculated transfer factor of Z3SU and Z35U range from 5.9 × 10^-4to 14.6 × 10^-4 for 238U and 4.9 × 10^-4 to 16.1 × 10^-4 for 235U. External absorbed dose rates were calculated to be in the range from 12.42 to 266.00 nGy/h. The annual effective dose was found to vary from 28.94 to 619.78 μSv/y. The annual internal effective dose due to 23SU and 23SU for fresh weights ofvegetablesl were found to vary from 0.9 × 10^-3 to 35.1 × 10^-3 μSv/y for 238U and 0.61 × 10^-4 to 17.62 × 10^-4 μSv/y for 235U.
