A hybrid approach using MLD (mixed logical dynamical) framework to handle infeasibility and constraint prioritization issues in MPC (model predictive control) based on input-output model is introduced. By expressing c...A hybrid approach using MLD (mixed logical dynamical) framework to handle infeasibility and constraint prioritization issues in MPC (model predictive control) based on input-output model is introduced. By expressing constraint priorities as propositional logics and by transforming the propositional logics into inequalities,the infeasibility and constraint prioritization issues are solved in the MPC. Constraints with higher priorities are met first, and then these with lower priorities are satisfied as much as possible. This new approach is illustrated in the control of a heavy oil fractionator-Shell column. The overall control performance has been significantly improved through the infeasibility and control priorities handling.展开更多
Synthesis of monoglycerides with Cinnamomum burmannii seeds oil and its application in moisturizing cream were studied. The results showed that the optimal transesterification conditions of synthesis of monoglycerides...Synthesis of monoglycerides with Cinnamomum burmannii seeds oil and its application in moisturizing cream were studied. The results showed that the optimal transesterification conditions of synthesis of monoglycerides with Cinnamomum burmannii seeds oil were as follows： the glycerol to oil molar ratio of 3 ： 1 ; NaOH catalyst dosage of 0.8% of the oil mass; reaction temperature of 180 ℃ for 3 hours; and the yield reached 62.6% . The crude product was purified by molecular distillation and the purity of the final product achieved 92.8%. Physicochemical properties of moisturizing cream prepared by using the final product can meet the requirements of China National Standard and the cosmetic product displayed good performance in application.展开更多
The aim of this research was to develop the porous spherical cellulose production from corn cob as an exfoliating agent for cosmetic industries. In process development of the porous spherical cellulose production from...The aim of this research was to develop the porous spherical cellulose production from corn cob as an exfoliating agent for cosmetic industries. In process development of the porous spherical cellulose production from corn cob, it was found that alkaline extraction with 10% sodiumhydroxide gave 85.86% purity of cellulose and the crystallinity index of the pulp of 76.08%. Then, the obtained pulp was extracted with acid sodium chlorite. It was found that the acid sodium chlorite extraction increased the cellulose from 85.86% to 91.86%. The obtained pulp was hydrolyse dwithdilute hydrochloric solution. The result shows that the crystallinity increased from 71.13% to 86.31% with smaller crystallite size compared to that obtained acid sodium chlorite extraction. The hydrolysis pulp was used to prepare porous spherical cellulose which has homogeneous and rough surface. The porosity and pore volume of the porous spherical cellulose increased when the amount of calcium carbonate as porogen was increased. The porous spherical cellulose was prepared from the optimized conditions and the physical and chemical properties were analysed and compared with standard commercial beads （Sephadex G-25）. It was found that the porous spherical cellulose had particle size and pH value similar to the standard value. Hazardous substances such as arsenic, lead and mercury were not found in the obtained porous spherical cellulose. The consumers test shows that 87~/＇0 of consumers accepted the product and the overall complacency was great.展开更多
基金Supported by the 973 Program (No. 2002CB312200)National High Tech. Project of China (863/CIMS 2004AA412050).
文摘A hybrid approach using MLD (mixed logical dynamical) framework to handle infeasibility and constraint prioritization issues in MPC (model predictive control) based on input-output model is introduced. By expressing constraint priorities as propositional logics and by transforming the propositional logics into inequalities,the infeasibility and constraint prioritization issues are solved in the MPC. Constraints with higher priorities are met first, and then these with lower priorities are satisfied as much as possible. This new approach is illustrated in the control of a heavy oil fractionator-Shell column. The overall control performance has been significantly improved through the infeasibility and control priorities handling.
文摘Synthesis of monoglycerides with Cinnamomum burmannii seeds oil and its application in moisturizing cream were studied. The results showed that the optimal transesterification conditions of synthesis of monoglycerides with Cinnamomum burmannii seeds oil were as follows： the glycerol to oil molar ratio of 3 ： 1 ; NaOH catalyst dosage of 0.8% of the oil mass; reaction temperature of 180 ℃ for 3 hours; and the yield reached 62.6% . The crude product was purified by molecular distillation and the purity of the final product achieved 92.8%. Physicochemical properties of moisturizing cream prepared by using the final product can meet the requirements of China National Standard and the cosmetic product displayed good performance in application.
文摘The aim of this research was to develop the porous spherical cellulose production from corn cob as an exfoliating agent for cosmetic industries. In process development of the porous spherical cellulose production from corn cob, it was found that alkaline extraction with 10% sodiumhydroxide gave 85.86% purity of cellulose and the crystallinity index of the pulp of 76.08%. Then, the obtained pulp was extracted with acid sodium chlorite. It was found that the acid sodium chlorite extraction increased the cellulose from 85.86% to 91.86%. The obtained pulp was hydrolyse dwithdilute hydrochloric solution. The result shows that the crystallinity increased from 71.13% to 86.31% with smaller crystallite size compared to that obtained acid sodium chlorite extraction. The hydrolysis pulp was used to prepare porous spherical cellulose which has homogeneous and rough surface. The porosity and pore volume of the porous spherical cellulose increased when the amount of calcium carbonate as porogen was increased. The porous spherical cellulose was prepared from the optimized conditions and the physical and chemical properties were analysed and compared with standard commercial beads （Sephadex G-25）. It was found that the porous spherical cellulose had particle size and pH value similar to the standard value. Hazardous substances such as arsenic, lead and mercury were not found in the obtained porous spherical cellulose. The consumers test shows that 87~/＇0 of consumers accepted the product and the overall complacency was great.
