[Objective] This study aimed to establish an efficient process for separation of phycoerythrin by using Q Sepharose Fast Flow resin and verity its feasibility for scale-up. [Method] Elution gradient, sample volume and...[Objective] This study aimed to establish an efficient process for separation of phycoerythrin by using Q Sepharose Fast Flow resin and verity its feasibility for scale-up. [Method] Elution gradient, sample volume and flow rate were optimized to determine the optimal separation condition, under which the scale-up process was verified. [Result] The optimal condition for separation of phycoerythrin by using Q Sepharose FF resin was investigated: 30 ml of laver extract was loaded to the Q Sepharose FF column with a bed volume of 8 ml; subsequently, the column was stepwise eluted with 0-0.10-0.35-1.00 mol/L NaCI solution (pH 6.0) at a constant flow rate of 1 ml/min; the elution peak under 0.35 mol/L NaCI solution was collected, and the recovery rate and purity coefficient (A565/A280) of phycoerythrin were determined as 44.3 and 1.15, respectively. Based on the established process, 75 ml of phycoerythrin extract was loaded to the Q Sepharose FF column with a bed volume of 20 ml for separation, while no significant variation was observed in the separation result. [Conclusion] Phycoerythrin can be well separated from laver extract by using Q Sepharose FF resin and the process is feasible for scale-up.展开更多
Membrane-based separation processes are new technology combined membrane separation with conventional separation. Hydrophobic porous membranes are often used in these processes. The structure of hydrophobic porous mem...Membrane-based separation processes are new technology combined membrane separation with conventional separation. Hydrophobic porous membranes are often used in these processes. The structure of hydrophobic porous membrane has significant effect on mass transfer process. The permeabilities of five kinds of gas, He, N2, O2, CO2 and water vapor, across six polytetrafluoroethylene(PTFE) flat membranes were tested experimentally. Results indicated that the greater the membrane mean pore size and the wider the pore size distribution are, the higher the gas permeability. A gas permeation model, including the effects of membrane structure parameter and gas properties, was established. A comprehensive characteristic parameter (including porosity, thickness and tortuosity) was found more effective to express the influence of membrane structure in gas permeation process. The predicted permeation coefficients were in good agreement with experimental data.展开更多
Value is the internal driving force for any corporate to obtain profits. The key issue of making profit lies on whether the corporate can truly appreciate the needs and combination of stakeholders' value, and establi...Value is the internal driving force for any corporate to obtain profits. The key issue of making profit lies on whether the corporate can truly appreciate the needs and combination of stakeholders' value, and establish a successful management of value exchange system. This paper starts with the theories of the employee and customer value measurement and management, followed by the value exchange system of employee-customer-organization. Therefore, it explains the status and role of employee-customer-organization in terms of value exchange. This work concludes that customers' satisfaction is determined by employees' satisfaction, and on that basis, customers would provide the promoted value to the organization.展开更多
基金Supported by National Natural Science Foundation of China(51143012)Natural Science Foundation of Shandong Province(ZR2009BM006)~~
文摘[Objective] This study aimed to establish an efficient process for separation of phycoerythrin by using Q Sepharose Fast Flow resin and verity its feasibility for scale-up. [Method] Elution gradient, sample volume and flow rate were optimized to determine the optimal separation condition, under which the scale-up process was verified. [Result] The optimal condition for separation of phycoerythrin by using Q Sepharose FF resin was investigated: 30 ml of laver extract was loaded to the Q Sepharose FF column with a bed volume of 8 ml; subsequently, the column was stepwise eluted with 0-0.10-0.35-1.00 mol/L NaCI solution (pH 6.0) at a constant flow rate of 1 ml/min; the elution peak under 0.35 mol/L NaCI solution was collected, and the recovery rate and purity coefficient (A565/A280) of phycoerythrin were determined as 44.3 and 1.15, respectively. Based on the established process, 75 ml of phycoerythrin extract was loaded to the Q Sepharose FF column with a bed volume of 20 ml for separation, while no significant variation was observed in the separation result. [Conclusion] Phycoerythrin can be well separated from laver extract by using Q Sepharose FF resin and the process is feasible for scale-up.
基金Supported by the 863 Hi-Tech. Research and Development Program of China (No. 2002AA649280, No. 2002AA304030),National Natural Science Foundation of China (No. 20206002), Beijing NOVA program (H013610250112), University Doctor Science Foundation of China
文摘Membrane-based separation processes are new technology combined membrane separation with conventional separation. Hydrophobic porous membranes are often used in these processes. The structure of hydrophobic porous membrane has significant effect on mass transfer process. The permeabilities of five kinds of gas, He, N2, O2, CO2 and water vapor, across six polytetrafluoroethylene(PTFE) flat membranes were tested experimentally. Results indicated that the greater the membrane mean pore size and the wider the pore size distribution are, the higher the gas permeability. A gas permeation model, including the effects of membrane structure parameter and gas properties, was established. A comprehensive characteristic parameter (including porosity, thickness and tortuosity) was found more effective to express the influence of membrane structure in gas permeation process. The predicted permeation coefficients were in good agreement with experimental data.
文摘Value is the internal driving force for any corporate to obtain profits. The key issue of making profit lies on whether the corporate can truly appreciate the needs and combination of stakeholders' value, and establish a successful management of value exchange system. This paper starts with the theories of the employee and customer value measurement and management, followed by the value exchange system of employee-customer-organization. Therefore, it explains the status and role of employee-customer-organization in terms of value exchange. This work concludes that customers' satisfaction is determined by employees' satisfaction, and on that basis, customers would provide the promoted value to the organization.