Objective:To test the characteristics of hyaluronic acid(HA)derivative cross-linked by polyethylene glycol films of low water content.Methods:The cross-linked HA film with 200μm thickness was got at atmospheric press...Objective:To test the characteristics of hyaluronic acid(HA)derivative cross-linked by polyethylene glycol films of low water content.Methods:The cross-linked HA film with 200μm thickness was got at atmospheric pressure at 25℃for 5 d.After dried,cross-linked films of 10 mm×10 mm were weighed and immersed in phosphate buffered saline (PBS pH 7.45)at 37℃for 24 h.Then the solution fraction and water content were estimated.Meanwhile,cross-linked HA derivative films were immersed in phosphate buffered saline(PBS:pH 7.45)at 37℃for determined time and then implanted subcutaneously in the back of white rats to test in vitro or in vivo degradation characteristic.Results and Conclusion:HA hydrogel cross-linked by polyethylene glycol with water content is as low as 60% and this kind of HA derivative has a slow degradation rate.展开更多
This study investigated the prospect of using aqueous mixture of 1-butylpyridinium tetrafluoroborate （[Bpy][BF4]） ionic liquid （IL） and monoethanolamine （MEA） as solvent in post-combustion CO2 capture （PCC） pr...This study investigated the prospect of using aqueous mixture of 1-butylpyridinium tetrafluoroborate （[Bpy][BF4]） ionic liquid （IL） and monoethanolamine （MEA） as solvent in post-combustion CO2 capture （PCC） process. This is done by analysis of the process through modelling and simulation. In literature, reported PCC models with a mixture of IL and MEA solvent were developed using equilibrium-based mass transfer approach. In contrast, the model in this study is developed using rate-based mass transfer approach in Aspen Plus. From the results, the mixed aqueous solvent with 5-30 wt% IL and 30 wt% MEA showed 7%-9% and 12%-27% less specific regeneration energy and solvent circulation rate respectively compared to commonly used 30 wt% MEA solvent. It is concluded that the ｜L concentration （wt%） in the solvent blend have significant impact on specific regeneration energy and solvent circulation rate. This study is a starting point for further research on technical and economic analysis of PCC process with aqueous blend of IL and MEA as solvent.展开更多
With rutin standard sample as the comparison, flavonoid extraction rate as an indicator, UV-2450 ultraviolet visible light spectrophotometer to measure flavonoid content in planted Trollius chinensis through orthogona...With rutin standard sample as the comparison, flavonoid extraction rate as an indicator, UV-2450 ultraviolet visible light spectrophotometer to measure flavonoid content in planted Trollius chinensis through orthogonal experiment, this experiment optimizes process condition of flavonoid in Trollius chinensis through water extraction and ethanol extraction. The result shows that flavonoid extraction rate of Trollius chinensis through ethanol extraction method is obviously higher than water extraction, and the optimal extraction process condition is： ethanol concentration is 75%, extraction time is 90min, extraction times are 3, and fluid material ratio is 20：1.展开更多
[Objective]The aim was to find a way to measure the cholesterol content in deserted oil.[Method]Dual-wavelength spectrophotometry method was used for the determination of cholesterol in edible oil.630 nm and 720 nm we...[Objective]The aim was to find a way to measure the cholesterol content in deserted oil.[Method]Dual-wavelength spectrophotometry method was used for the determination of cholesterol in edible oil.630 nm and 720 nm were set as target band and reference band in this method,respectively.The result was compared to liquid chromatography method.[Result]The relative standard deviation(RSD)was at 1.26% and recovery was between 101.9% and 110.7%.Linear range was 8.0-40.0 μg/ml.The tested result was close to the result of liquid chromatography.[Conclusion]It was proved that this method was easy,fast and accurate.The disturbance of sitosterol was eliminated without isolation.It can be used for fast identification of the authenticity of waste fat.展开更多
文摘Objective:To test the characteristics of hyaluronic acid(HA)derivative cross-linked by polyethylene glycol films of low water content.Methods:The cross-linked HA film with 200μm thickness was got at atmospheric pressure at 25℃for 5 d.After dried,cross-linked films of 10 mm×10 mm were weighed and immersed in phosphate buffered saline (PBS pH 7.45)at 37℃for 24 h.Then the solution fraction and water content were estimated.Meanwhile,cross-linked HA derivative films were immersed in phosphate buffered saline(PBS:pH 7.45)at 37℃for determined time and then implanted subcutaneously in the back of white rats to test in vitro or in vivo degradation characteristic.Results and Conclusion:HA hydrogel cross-linked by polyethylene glycol with water content is as low as 60% and this kind of HA derivative has a slow degradation rate.
文摘This study investigated the prospect of using aqueous mixture of 1-butylpyridinium tetrafluoroborate （[Bpy][BF4]） ionic liquid （IL） and monoethanolamine （MEA） as solvent in post-combustion CO2 capture （PCC） process. This is done by analysis of the process through modelling and simulation. In literature, reported PCC models with a mixture of IL and MEA solvent were developed using equilibrium-based mass transfer approach. In contrast, the model in this study is developed using rate-based mass transfer approach in Aspen Plus. From the results, the mixed aqueous solvent with 5-30 wt% IL and 30 wt% MEA showed 7%-9% and 12%-27% less specific regeneration energy and solvent circulation rate respectively compared to commonly used 30 wt% MEA solvent. It is concluded that the ｜L concentration （wt%） in the solvent blend have significant impact on specific regeneration energy and solvent circulation rate. This study is a starting point for further research on technical and economic analysis of PCC process with aqueous blend of IL and MEA as solvent.
文摘With rutin standard sample as the comparison, flavonoid extraction rate as an indicator, UV-2450 ultraviolet visible light spectrophotometer to measure flavonoid content in planted Trollius chinensis through orthogonal experiment, this experiment optimizes process condition of flavonoid in Trollius chinensis through water extraction and ethanol extraction. The result shows that flavonoid extraction rate of Trollius chinensis through ethanol extraction method is obviously higher than water extraction, and the optimal extraction process condition is： ethanol concentration is 75%, extraction time is 90min, extraction times are 3, and fluid material ratio is 20：1.
基金Supported by National Quality Inspection Bureau(KJ092102,2009QK146)
文摘[Objective]The aim was to find a way to measure the cholesterol content in deserted oil.[Method]Dual-wavelength spectrophotometry method was used for the determination of cholesterol in edible oil.630 nm and 720 nm were set as target band and reference band in this method,respectively.The result was compared to liquid chromatography method.[Result]The relative standard deviation(RSD)was at 1.26% and recovery was between 101.9% and 110.7%.Linear range was 8.0-40.0 μg/ml.The tested result was close to the result of liquid chromatography.[Conclusion]It was proved that this method was easy,fast and accurate.The disturbance of sitosterol was eliminated without isolation.It can be used for fast identification of the authenticity of waste fat.
