Steam generator is optimized by applying entransy dissipation extremum principle and constructal theory and adopting analyti-cal method.The obtained results show that the optimal spacing between adjacent tubes,the mas...Steam generator is optimized by applying entransy dissipation extremum principle and constructal theory and adopting analyti-cal method.The obtained results show that the optimal spacing between adjacent tubes,the mass flow rate of gas and the maximum entransy dissipation rate all depend on the dimensionless diameter of one tube,the dimensionless pressure difference number and the dimensionless length of flow channel of gas.Besides the three dimensionless groups,the optimal numbers of riser tubes and downcomer tubes and their summation all depend on the dimensionless height of one tube.The maximum entransy dissipation rate increases as the pressure difference that drives the gas flowing increases,and as the diameter of one tube and the length of flow channel both decrease.The mean heat flux in the heat transfer process of hot gas grows greatly,and the performance of the system is improved.Compared with the optimal construct with heat transfer rate maximization,the optimal construct with entransy dissipation rate maximization can improved the heat transfer effect of the steam generator more.展开更多
To observe the effect of Fufang Jisheng Liujin Gao （复方寄生流浸膏 Compound Mistletoe Fluidextract） on blood pressure in the spontaneous hypertensive rats （SHR） and the renal hypertensive dogs （RHD）. Methods： T...To observe the effect of Fufang Jisheng Liujin Gao （复方寄生流浸膏 Compound Mistletoe Fluidextract） on blood pressure in the spontaneous hypertensive rats （SHR） and the renal hypertensive dogs （RHD）. Methods： The blood pressure-decreasing effects of single administration and 14-day consecutive administration of Compound Mistletoe Fluidextract （CMF） in SHR and RHD were investigated and compared with that of Niuhuang Jiangya Wan （牛黄降压丸 Bezoar Hypertension-relieving Pills）. Results： Both single administration and 14-day consecutive administration of CMF had significant hypotensive effects in SHR and RHD. Conclusion： The hypotensive action of CMF is gradual, but lasts for a longer period, with a dose-effect relationship in a range of doses.展开更多
基金supported by the National Natural Science Foundation of China (Grant No 10905093)the Program for New Century Excellent Talents in University of China (Grant No NCET-04-1006)the Foun-dation for the Author of National Excellent Doctoral Dissertation of China (Grant No 200136)
文摘Steam generator is optimized by applying entransy dissipation extremum principle and constructal theory and adopting analyti-cal method.The obtained results show that the optimal spacing between adjacent tubes,the mass flow rate of gas and the maximum entransy dissipation rate all depend on the dimensionless diameter of one tube,the dimensionless pressure difference number and the dimensionless length of flow channel of gas.Besides the three dimensionless groups,the optimal numbers of riser tubes and downcomer tubes and their summation all depend on the dimensionless height of one tube.The maximum entransy dissipation rate increases as the pressure difference that drives the gas flowing increases,and as the diameter of one tube and the length of flow channel both decrease.The mean heat flux in the heat transfer process of hot gas grows greatly,and the performance of the system is improved.Compared with the optimal construct with heat transfer rate maximization,the optimal construct with entransy dissipation rate maximization can improved the heat transfer effect of the steam generator more.
文摘To observe the effect of Fufang Jisheng Liujin Gao （复方寄生流浸膏 Compound Mistletoe Fluidextract） on blood pressure in the spontaneous hypertensive rats （SHR） and the renal hypertensive dogs （RHD）. Methods： The blood pressure-decreasing effects of single administration and 14-day consecutive administration of Compound Mistletoe Fluidextract （CMF） in SHR and RHD were investigated and compared with that of Niuhuang Jiangya Wan （牛黄降压丸 Bezoar Hypertension-relieving Pills）. Results： Both single administration and 14-day consecutive administration of CMF had significant hypotensive effects in SHR and RHD. Conclusion： The hypotensive action of CMF is gradual, but lasts for a longer period, with a dose-effect relationship in a range of doses.
