A microfluidic device was developed for flow cytometry and single cell fluorescence detection. TO-PRO-3 as a vital DNA dye was used to label dead cells and some of apoptosis cells which could be penetrated from their ...A microfluidic device was developed for flow cytometry and single cell fluorescence detection. TO-PRO-3 as a vital DNA dye was used to label dead cells and some of apoptosis cells which could be penetrated from their broken membranes and intercalated into DNA chains. Cells were driven by combined effect of hydrodynamic and electric power and passed through the detection point one by one in micro channels. A laser induced fluorescence detection system which employed a 635 nm semiconductor laser was the only measurement of the whole system. This micro flow cytometor system was applied to estimate the damage degree of those HeLa cells having been exposed to ultraviolet radiation for 10, 20 and 40 min, respectively by the number of cells determined and their fluorescence intensity.展开更多
Based on RNG k-ε turbulence model and sliding grid technique, solid-liquid two-phase three-dimensional(3-D) unsteady turbulence of full passage in slurry pump was simulated by means of Fluent software. The effects of...Based on RNG k-ε turbulence model and sliding grid technique, solid-liquid two-phase three-dimensional(3-D) unsteady turbulence of full passage in slurry pump was simulated by means of Fluent software. The effects of unsteady flow characteristics on solid-liquid two-phase flow and pump performance were researched under design condition. The results show that clocking effect has a significant influence on the flow in pump, and the fluctuation of flow velocity and pressure is obvious, particularly near the volute tongue, at the position of small sections of volute and within diffuser. Clocking effect has a more influence on liquid-phase than on solid-phase, and the wake-jet structure of relative velocity of solid-phase is less obvious than liquid-phase near the volute tongue and the impeller passage outlet. The fluctuation of relative velocity of solid-phase flow is 7.6% smaller than liquid-phase flow at the impeller outlet on circular path. Head and radial forces of the impeller are 8.1% and 85.7% of fluctuation, respectively. The results provide a theoretical basis for further research for turbulence, improving efficient, reducing the hydraulic losses and wear. Finally, field tests were carried out to verify the operation and wear of slurry pump.展开更多
文摘A microfluidic device was developed for flow cytometry and single cell fluorescence detection. TO-PRO-3 as a vital DNA dye was used to label dead cells and some of apoptosis cells which could be penetrated from their broken membranes and intercalated into DNA chains. Cells were driven by combined effect of hydrodynamic and electric power and passed through the detection point one by one in micro channels. A laser induced fluorescence detection system which employed a 635 nm semiconductor laser was the only measurement of the whole system. This micro flow cytometor system was applied to estimate the damage degree of those HeLa cells having been exposed to ultraviolet radiation for 10, 20 and 40 min, respectively by the number of cells determined and their fluorescence intensity.
基金Project(51375498)supported by the National Natural Science Foundation of China
文摘Based on RNG k-ε turbulence model and sliding grid technique, solid-liquid two-phase three-dimensional(3-D) unsteady turbulence of full passage in slurry pump was simulated by means of Fluent software. The effects of unsteady flow characteristics on solid-liquid two-phase flow and pump performance were researched under design condition. The results show that clocking effect has a significant influence on the flow in pump, and the fluctuation of flow velocity and pressure is obvious, particularly near the volute tongue, at the position of small sections of volute and within diffuser. Clocking effect has a more influence on liquid-phase than on solid-phase, and the wake-jet structure of relative velocity of solid-phase is less obvious than liquid-phase near the volute tongue and the impeller passage outlet. The fluctuation of relative velocity of solid-phase flow is 7.6% smaller than liquid-phase flow at the impeller outlet on circular path. Head and radial forces of the impeller are 8.1% and 85.7% of fluctuation, respectively. The results provide a theoretical basis for further research for turbulence, improving efficient, reducing the hydraulic losses and wear. Finally, field tests were carried out to verify the operation and wear of slurry pump.
