[Objective] The aim was to study on impacts of excessive soaking N, P, and K insubstrate plots of and seedling growth. [Method] Substrate was designed to add additional 1/2 water after saturation and expansion. Dispos...[Objective] The aim was to study on impacts of excessive soaking N, P, and K insubstrate plots of and seedling growth. [Method] Substrate was designed to add additional 1/2 water after saturation and expansion. Disposable excessive soak- ing and regression relation of nutrition infusion of substrate plots were studied by design of 13 time gradient. Plant nutrition absorption and growth effects after sub- strate plots immersed by water were investigated by growing tomato. [Result] Con- centration and time of the three nutrition immersed in water had the regression equation of each, as follows： N=-2E-05t2＋0.016 lt＋2.0553, P=0.002 2t＋2.248 5 and K=0.004 7t＋0.875 8. With nutrition loss of the three, however, loss amount was al- most same with variance analysis of regression equation, which may result from its volatilization. Regression equations of P and K were： P=0.125 7t-0.117, and K=0.022 5t.1514, which led to adverse impact on plant absorption of N and K above ground, whose equations were N=20.64e-4E-0.4t, and K=E-06t2-0.011 3t＋29.055. Meanwhile, un- der the condition, sound seedling index was not impacted a lot by excessive immer- sion. [Conclusion] This study has provided theoretical reference for guidance of sub- strate plot soaking method, cultivation and regulation, and breeding, as well as agri- cultural production.展开更多
Using poly（acrylic acid） （PAA） aqueous solution, NaOH aqueous solution, aniline （An） and ammonium persulfate （APS）, PAn-PAA hydrogels with a semi-interpenetrating structure connected by physical interlocks, ch...Using poly（acrylic acid） （PAA） aqueous solution, NaOH aqueous solution, aniline （An） and ammonium persulfate （APS）, PAn-PAA hydrogels with a semi-interpenetrating structure connected by physical interlocks, chemical ion bonds and hydrogen bonds were prepared. The swelling properties of the hydrogels in solutions of different pH values （adjusted by adding NaOH or HCI） were studied. All the hydrogels prepared have similar swelling curves （the curves of equilibrium swelling ratio vs. pH value） and reach their maximum swelling at pH of 8 - 10. The maximum swelling ratio of the hydrogels is dependent on composition, including molecular weight of PAA, polymer content of the hydrogel, and molar ratios of AA to An, APS to An, and NaOH to AA, And the compositional dependence of the swelling capacity of PAn-PAA hydrogels was also studied.展开更多
Switching expansion reduction(SER) uses a switch valve to substitute the throttle valve to reduce pressure for high pressure pneumatics.The experiments indicate that the simulation model well predicts the actual chara...Switching expansion reduction(SER) uses a switch valve to substitute the throttle valve to reduce pressure for high pressure pneumatics.The experiments indicate that the simulation model well predicts the actual characteristics.The heat transfers and polytropic exponents of the air in expansion tank and supply tanks of SER have been studied on the basis of the experiments and the simulation model.Through the mathematical reasoning in this paper,the polytropic exponent can be calculated by the air mass,heat,and work exchanges of the pneumatic container.For the air in a constant volume tank,when the heat-absorption is large enough to raise air temperature in discharging process,the polytropic exponent is less than 1;when the air is experiencing a discharging and heat-releasing process,the polytropic exponent exceeds the specific heat ratio(the value of 1.4).展开更多
基金Supported by Action Programs of Service Business of Scientists and Engineers in MOST(2009GJA00026)Science and Technology Project of Beijing Municipal Bureau of Agriculture(2010020101)+1 种基金Science and Technology project of Beijing Municipal Bureau of Agriculture(011050465100002)Science and Technology Project of Beijing Academy of Agricultural and Forestry Sciences(2010A016)~~
文摘[Objective] The aim was to study on impacts of excessive soaking N, P, and K insubstrate plots of and seedling growth. [Method] Substrate was designed to add additional 1/2 water after saturation and expansion. Disposable excessive soak- ing and regression relation of nutrition infusion of substrate plots were studied by design of 13 time gradient. Plant nutrition absorption and growth effects after sub- strate plots immersed by water were investigated by growing tomato. [Result] Con- centration and time of the three nutrition immersed in water had the regression equation of each, as follows： N=-2E-05t2＋0.016 lt＋2.0553, P=0.002 2t＋2.248 5 and K=0.004 7t＋0.875 8. With nutrition loss of the three, however, loss amount was al- most same with variance analysis of regression equation, which may result from its volatilization. Regression equations of P and K were： P=0.125 7t-0.117, and K=0.022 5t.1514, which led to adverse impact on plant absorption of N and K above ground, whose equations were N=20.64e-4E-0.4t, and K=E-06t2-0.011 3t＋29.055. Meanwhile, un- der the condition, sound seedling index was not impacted a lot by excessive immer- sion. [Conclusion] This study has provided theoretical reference for guidance of sub- strate plot soaking method, cultivation and regulation, and breeding, as well as agri- cultural production.
文摘Using poly（acrylic acid） （PAA） aqueous solution, NaOH aqueous solution, aniline （An） and ammonium persulfate （APS）, PAn-PAA hydrogels with a semi-interpenetrating structure connected by physical interlocks, chemical ion bonds and hydrogen bonds were prepared. The swelling properties of the hydrogels in solutions of different pH values （adjusted by adding NaOH or HCI） were studied. All the hydrogels prepared have similar swelling curves （the curves of equilibrium swelling ratio vs. pH value） and reach their maximum swelling at pH of 8 - 10. The maximum swelling ratio of the hydrogels is dependent on composition, including molecular weight of PAA, polymer content of the hydrogel, and molar ratios of AA to An, APS to An, and NaOH to AA, And the compositional dependence of the swelling capacity of PAn-PAA hydrogels was also studied.
基金supported by the National Natural Science Foundation of China (No.50575202)
文摘Switching expansion reduction(SER) uses a switch valve to substitute the throttle valve to reduce pressure for high pressure pneumatics.The experiments indicate that the simulation model well predicts the actual characteristics.The heat transfers and polytropic exponents of the air in expansion tank and supply tanks of SER have been studied on the basis of the experiments and the simulation model.Through the mathematical reasoning in this paper,the polytropic exponent can be calculated by the air mass,heat,and work exchanges of the pneumatic container.For the air in a constant volume tank,when the heat-absorption is large enough to raise air temperature in discharging process,the polytropic exponent is less than 1;when the air is experiencing a discharging and heat-releasing process,the polytropic exponent exceeds the specific heat ratio(the value of 1.4).
