By means of the computational fluid dynamics software Fluent 6.3, a mathematical model of three-dimensional three-phase fluid flow field in the molten bath of electric arc furnace (EAF) with side accessorial oxygen ...By means of the computational fluid dynamics software Fluent 6.3, a mathematical model of three-dimensional three-phase fluid flow field in the molten bath of electric arc furnace (EAF) with side accessorial oxygen lances was developed to study the transient phenomena of oxygen jet impingement on the molten steel and the molten slag. The water modeling experiment was carried out to verify the simulation results. The impingement of the supersonic oxygen jet caused impact dent on the molten steel surface accordingly. The area of impact dent changed almost in linear relationship to flow rate of oxygen jet, which can be expressed by a deduced mathematical equation. And the relationship between the impact force of oxygen iet and the correspondingly formed apparent static pressure on molten bath was obtained, which was in linear relationship and a direct proportion, and can also be expressed by a deduced mathematical equation.展开更多
A double-parameter oxygen lance used in a 300 t converter was designed to improve the metallurgical performance. A small-scale measurement of the jet behavior was done using a computer controlled scanning system. The ...A double-parameter oxygen lance used in a 300 t converter was designed to improve the metallurgical performance. A small-scale measurement of the jet behavior was done using a computer controlled scanning system. The experimental data on the velocity distribution at the jet centerline, the contour map of the jet velocity, the deviation of the jet centerline, and the velocity distribution of the axial section were compiled. According to the results of the small-scale measurement, the double-parameter lance was also employed for a BOF experiment. The metallurgy inde- xes show that the metallurgical performance was highly promoted by use of the double-parameter lance.展开更多
Dear Editor,Soldiers or people in battlefield settings are frequently injured with acute trauma, resulting in respiratory depression, hypoxia and associated morbidity and mortality. Traumatic brain injury(TBI) is with...Dear Editor,Soldiers or people in battlefield settings are frequently injured with acute trauma, resulting in respiratory depression, hypoxia and associated morbidity and mortality. Traumatic brain injury(TBI) is with as much as 80%–90% of mild to moderate in combat casualties and contributed significantly to morbidity and mortality in battlefield settings. Correction of hypoxia at as capable as possible is expected to reduce or minimize the morbidity/mortality due to acute brain injury. An easy, quick and safe setup to promote oxygenation/ventilation of injured military personnel or peoples by non-medical personnel in battlefield settings immediately after acute injury before transfer to hospital is expected to reduce the morbidity/mortality due to injury mediated respiratory depression.展开更多
The crystalline fullerene C60 particles were formed and immobilized on poly(dimethylsiloxane) (PDMS) substrates under the various discharge conditions by an ink-jet method, and investigated for the reactive oxygen spe...The crystalline fullerene C60 particles were formed and immobilized on poly(dimethylsiloxane) (PDMS) substrates under the various discharge conditions by an ink-jet method, and investigated for the reactive oxygen species (ROS) generation property under visible light irradiation. The particles were synthesized by discharging a toluene solution dissolved C60 and poly(methyl methacrylate) (PMMA) with the ink-jet spotting system. The ROS generation was evaluated by comparisons of the fluorescence intensities measured for the formed particles under green laser irradiation and in a dark room using fluorescent dyes, 2’,7’-dichlorofluorescein diacetate and dihydroethidium. The results of transmission electron microscope (TEM) observation showed that the formed particles consisted of crystalline C60. The optimal ink-jet discharge conditions for synthesizing the particles to generate more ROS were found. In the case of the optimal conditions, the structure in which the needle-like particles were three-dimensionally formed was confirmed. The surface area of the crystalline C60 particles was calculated using the SEM observation results, and it was suggested that when the needle-like finer particles were three-dimensionally formed under the optimal conditions, increasing the surface area lead to an increase in the ROS generation amount.展开更多
基金Sponsored by National Key Technology Research and Development Program in 11th Five-year Plan of China(2008AF33B01)Fuzhou University Foundation for Development of Science and Technology of China(0020-600588)
文摘By means of the computational fluid dynamics software Fluent 6.3, a mathematical model of three-dimensional three-phase fluid flow field in the molten bath of electric arc furnace (EAF) with side accessorial oxygen lances was developed to study the transient phenomena of oxygen jet impingement on the molten steel and the molten slag. The water modeling experiment was carried out to verify the simulation results. The impingement of the supersonic oxygen jet caused impact dent on the molten steel surface accordingly. The area of impact dent changed almost in linear relationship to flow rate of oxygen jet, which can be expressed by a deduced mathematical equation. And the relationship between the impact force of oxygen iet and the correspondingly formed apparent static pressure on molten bath was obtained, which was in linear relationship and a direct proportion, and can also be expressed by a deduced mathematical equation.
文摘A double-parameter oxygen lance used in a 300 t converter was designed to improve the metallurgical performance. A small-scale measurement of the jet behavior was done using a computer controlled scanning system. The experimental data on the velocity distribution at the jet centerline, the contour map of the jet velocity, the deviation of the jet centerline, and the velocity distribution of the axial section were compiled. According to the results of the small-scale measurement, the double-parameter lance was also employed for a BOF experiment. The metallurgy inde- xes show that the metallurgical performance was highly promoted by use of the double-parameter lance.
文摘Dear Editor,Soldiers or people in battlefield settings are frequently injured with acute trauma, resulting in respiratory depression, hypoxia and associated morbidity and mortality. Traumatic brain injury(TBI) is with as much as 80%–90% of mild to moderate in combat casualties and contributed significantly to morbidity and mortality in battlefield settings. Correction of hypoxia at as capable as possible is expected to reduce or minimize the morbidity/mortality due to acute brain injury. An easy, quick and safe setup to promote oxygenation/ventilation of injured military personnel or peoples by non-medical personnel in battlefield settings immediately after acute injury before transfer to hospital is expected to reduce the morbidity/mortality due to injury mediated respiratory depression.
文摘The crystalline fullerene C60 particles were formed and immobilized on poly(dimethylsiloxane) (PDMS) substrates under the various discharge conditions by an ink-jet method, and investigated for the reactive oxygen species (ROS) generation property under visible light irradiation. The particles were synthesized by discharging a toluene solution dissolved C60 and poly(methyl methacrylate) (PMMA) with the ink-jet spotting system. The ROS generation was evaluated by comparisons of the fluorescence intensities measured for the formed particles under green laser irradiation and in a dark room using fluorescent dyes, 2’,7’-dichlorofluorescein diacetate and dihydroethidium. The results of transmission electron microscope (TEM) observation showed that the formed particles consisted of crystalline C60. The optimal ink-jet discharge conditions for synthesizing the particles to generate more ROS were found. In the case of the optimal conditions, the structure in which the needle-like particles were three-dimensionally formed was confirmed. The surface area of the crystalline C60 particles was calculated using the SEM observation results, and it was suggested that when the needle-like finer particles were three-dimensionally formed under the optimal conditions, increasing the surface area lead to an increase in the ROS generation amount.