An air source heat pump system (ASHPS) used in an office building is set up and studied experimentally. Its operating performance in winter is evaluated based on test data and a comparative discussion is given on the ...An air source heat pump system (ASHPS) used in an office building is set up and studied experimentally. Its operating performance in winter is evaluated based on test data and a comparative discussion is given on the effect of climate conditions and heating load ratio on the operation behavior. Then heating capacity variation caused by evaporator frosting is analyzed as well. Finally, the defrosting parameters and the technical feasibility are studied for a constant heating demand. The experimental results indicate that both the outlet water temperature drop and the system COP should be taken into account when setting defrosting parameters, and ASHPS is a viable technology for space heating and hot-water production in winter in Tianjin, which can maintain the room temperature above 19 ℃ when the outdoor temperature is -2 ℃.展开更多
A non invasive ultrasonic method is used to detect whether or not the frozen fish has suffered a partial or total accidental thawing. The time of flight and the peak to peak amplitude of the ultrasonic signals backsca...A non invasive ultrasonic method is used to detect whether or not the frozen fish has suffered a partial or total accidental thawing. The time of flight and the peak to peak amplitude of the ultrasonic signals backscattered by fish are recorded during thawing. The comparison of the evolution curves and images corresponding to first and second thawing shows indicators of accidental thawing. The monitoring of thawing process showed that its assessment can be reduced to the measurement of the water content lost by fish. The attempt to replace the original water lost by fish in first thawing is analyzed. The influence of the transducer frequency on fish thawing evaluation is tested.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
基金Supported bythe"11th Five-Year Plan"for National Plans of Major Technology Projects
文摘An air source heat pump system (ASHPS) used in an office building is set up and studied experimentally. Its operating performance in winter is evaluated based on test data and a comparative discussion is given on the effect of climate conditions and heating load ratio on the operation behavior. Then heating capacity variation caused by evaporator frosting is analyzed as well. Finally, the defrosting parameters and the technical feasibility are studied for a constant heating demand. The experimental results indicate that both the outlet water temperature drop and the system COP should be taken into account when setting defrosting parameters, and ASHPS is a viable technology for space heating and hot-water production in winter in Tianjin, which can maintain the room temperature above 19 ℃ when the outdoor temperature is -2 ℃.
文摘A non invasive ultrasonic method is used to detect whether or not the frozen fish has suffered a partial or total accidental thawing. The time of flight and the peak to peak amplitude of the ultrasonic signals backscattered by fish are recorded during thawing. The comparison of the evolution curves and images corresponding to first and second thawing shows indicators of accidental thawing. The monitoring of thawing process showed that its assessment can be reduced to the measurement of the water content lost by fish. The attempt to replace the original water lost by fish in first thawing is analyzed. The influence of the transducer frequency on fish thawing evaluation is tested.
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.
