Purification of original crude glycerol obtained from biodiesel production was conducted in a laboratory scale equipment by means of a combined chemical and physical treatment method based upon repeated cycles of acid...Purification of original crude glycerol obtained from biodiesel production was conducted in a laboratory scale equipment by means of a combined chemical and physical treatment method based upon repeated cycles of acidification of liquid phase to the desired pH value by using 5.85% H3PO4 solution for pH value adjustment, and the mixture was kept at 70 ℃ for 60 rain to make phase separation for obtaining a glycerol-rich middle phase. The yield of crude glycerol reached 81.2%. Subsequently, upon reaction of the obtained glycerol phase with 0.03% of sodium oxalate at 80 ℃ for 30 min the impurity removal rate was equal to 19.8%. The fraction boiling between 164 ℃ and 200 ℃ was collected by vacuum distil- lation followed by decolorization with 2% of active carbon at 80 ℃ for two times to yield the product glycerol with an ac- ceptable purity of 98.10%.展开更多
Outstanding progress regarding the pathophysiology of Crohn's disease (CD) has led to the development of innovative therapeutic concepts. Numerous controlled trials have been performed in CD. This review concentra...Outstanding progress regarding the pathophysiology of Crohn's disease (CD) has led to the development of innovative therapeutic concepts. Numerous controlled trials have been performed in CD. This review concentrates on the results of randomized,placebo-controlled trials,and meta-analyses when available,that provide the highest degree of evidence. Current guidelines on the management of CD recommend a step-up approach to treatment involving the addition of more powerful therapies as the severity of disease and refractoriness to therapy increase. The advent of biological drugs has opened new therapeutic horizons for treating CD,modifying the treatment goals. However,the large majority of patients with CD will be managed through conventional therapy,even if they are a prelude to biological therapy.展开更多
基金the financial support from Scientific Research Foundation for Doctoral Program of Liaoning Province(20081104)
文摘Purification of original crude glycerol obtained from biodiesel production was conducted in a laboratory scale equipment by means of a combined chemical and physical treatment method based upon repeated cycles of acidification of liquid phase to the desired pH value by using 5.85% H3PO4 solution for pH value adjustment, and the mixture was kept at 70 ℃ for 60 rain to make phase separation for obtaining a glycerol-rich middle phase. The yield of crude glycerol reached 81.2%. Subsequently, upon reaction of the obtained glycerol phase with 0.03% of sodium oxalate at 80 ℃ for 30 min the impurity removal rate was equal to 19.8%. The fraction boiling between 164 ℃ and 200 ℃ was collected by vacuum distil- lation followed by decolorization with 2% of active carbon at 80 ℃ for two times to yield the product glycerol with an ac- ceptable purity of 98.10%.
文摘Outstanding progress regarding the pathophysiology of Crohn's disease (CD) has led to the development of innovative therapeutic concepts. Numerous controlled trials have been performed in CD. This review concentrates on the results of randomized,placebo-controlled trials,and meta-analyses when available,that provide the highest degree of evidence. Current guidelines on the management of CD recommend a step-up approach to treatment involving the addition of more powerful therapies as the severity of disease and refractoriness to therapy increase. The advent of biological drugs has opened new therapeutic horizons for treating CD,modifying the treatment goals. However,the large majority of patients with CD will be managed through conventional therapy,even if they are a prelude to biological therapy.