The paper describes the ries with high thermal shock development of brick seresistance and low creep rate for hot blast stove, including research target and research plan on the basis of analysis on how to enhance the...The paper describes the ries with high thermal shock development of brick seresistance and low creep rate for hot blast stove, including research target and research plan on the basis of analysis on how to enhance the thermal shock resistance and to lower creep rate of the bricks. Efforts have been made on the selection of starting materials such as corundum, mullite, andalusite and sillimanite etc., together with some measures taken on multi-grade formulation, homogenizing of the matrix of bricks and addition of some special additives. The results indicated that the bricks were with characteristics such as higher thermal shock resistance of 〉 30 cycles under quenching in water from 1000℃, and creep rate of 0. 2 under 1400℃ for 20 -50hrs with load of 0.2 MPa. Now a series of products of this kind have been developed and produced. The application of the products in Wuhan Iron and Steel Co. showed very prospective results. Now most of domestic large sized blast furnaces say ≥- 1000m^3, including those of Baoshan Iron and Steel Co. , have selected the series products made by Gongyi No. 5 Refractories Head Factory(GYWN) for their hot blast stoves.展开更多
We present preliminary results from the experimental investigation of the response of the atmosphere due to the impact of powerful shock waves. The response is evidenced as ultra low frequency electromagnetic wave rad...We present preliminary results from the experimental investigation of the response of the atmosphere due to the impact of powerful shock waves. The response is evidenced as ultra low frequency electromagnetic wave radiation at frequency of 2-5 kHz and in duration of 3 7s. We hypothesize that this radiation appears due to the following process: the shock wave ionizes the neutral particles in the air and these charged and neutral particles continue their vertical motion, which forms in the trail of the shock wave. Such motion can cause the cyclotron-like radiation measured.展开更多
High-speed rotor rotation under the low-density condition creates a special low-Reynolds compressible flow around the rotor blade airfoil where the compressibility effect on the laminar separated shear layer occurs. H...High-speed rotor rotation under the low-density condition creates a special low-Reynolds compressible flow around the rotor blade airfoil where the compressibility effect on the laminar separated shear layer occurs. However, the compressibility effect and shock wave generation associated with the increase in the Mach number (M) and the trend change due to their interference have not been clarified. The purpose is to clear the compressibility effect and its impact of shock wave generation on the flow field and aerodynamics. Therefore, we perform a two-dimensional unsteady calculation by Computational fluid dynamics (CFD) analysis using the CLF5605 airfoil used in the Mars helicopter Ingenuity, which succeeded in its first flight on Mars. The calculation conditions are set to the Reynolds number (Re) at 75% rotor span in hovering (Re = 15,400), and the Mach number was varied from incompressible (M = 0.2) to transonic (M = 1.2). The compressible fluid dynamics solver FaSTAR developed by the Japan aerospace exploration agency (JAXA) is used, and calculations are performed under multiple conditions in which the Mach number and angle of attack (α) are swept. The results show that a flow field is similar to that in the Earth’s atmosphere above M = 1.0, such as bow shock at the leading edge, whereas multiple λ-type shock waves are observed over the separated shear layer above α = 3° at M = 0.80. However, no significant difference is found in the C<sub>p</sub> distribution around the airfoil between M = 0.6 and M = 0.8. From the results, it is found that multiple λ-type shock waves have no significant effect on the airfoil surface pressure distribution, the separated shear layer effect is dominant in the surface pressure change and aerodynamic characteristics.展开更多
血液复苏是严重失血患者的关键急救措施。血液复苏液体的选用,经历了从全血到晶体液/胶体液、晶体液联合红细胞、等比例血液成分的演进过程。近20年来,采用低效价抗体O型全血(low titer group O whole blood,LTOWB)作为血液复苏的首选...血液复苏是严重失血患者的关键急救措施。血液复苏液体的选用,经历了从全血到晶体液/胶体液、晶体液联合红细胞、等比例血液成分的演进过程。近20年来,采用低效价抗体O型全血(low titer group O whole blood,LTOWB)作为血液复苏的首选应急通用桥接复苏液,已发展成为大趋势。我们对全血在严重失血患者的应用历史和现状做一介绍,并提出我国采用LTOWB作为首选应急通用血液的进一步论证和验证研究建议。展开更多
基金The paper was presented at the Unitecr’05,which was held in Orlando. USA on Nov.8~11,2005
文摘The paper describes the ries with high thermal shock development of brick seresistance and low creep rate for hot blast stove, including research target and research plan on the basis of analysis on how to enhance the thermal shock resistance and to lower creep rate of the bricks. Efforts have been made on the selection of starting materials such as corundum, mullite, andalusite and sillimanite etc., together with some measures taken on multi-grade formulation, homogenizing of the matrix of bricks and addition of some special additives. The results indicated that the bricks were with characteristics such as higher thermal shock resistance of 〉 30 cycles under quenching in water from 1000℃, and creep rate of 0. 2 under 1400℃ for 20 -50hrs with load of 0.2 MPa. Now a series of products of this kind have been developed and produced. The application of the products in Wuhan Iron and Steel Co. showed very prospective results. Now most of domestic large sized blast furnaces say ≥- 1000m^3, including those of Baoshan Iron and Steel Co. , have selected the series products made by Gongyi No. 5 Refractories Head Factory(GYWN) for their hot blast stoves.
文摘We present preliminary results from the experimental investigation of the response of the atmosphere due to the impact of powerful shock waves. The response is evidenced as ultra low frequency electromagnetic wave radiation at frequency of 2-5 kHz and in duration of 3 7s. We hypothesize that this radiation appears due to the following process: the shock wave ionizes the neutral particles in the air and these charged and neutral particles continue their vertical motion, which forms in the trail of the shock wave. Such motion can cause the cyclotron-like radiation measured.
文摘High-speed rotor rotation under the low-density condition creates a special low-Reynolds compressible flow around the rotor blade airfoil where the compressibility effect on the laminar separated shear layer occurs. However, the compressibility effect and shock wave generation associated with the increase in the Mach number (M) and the trend change due to their interference have not been clarified. The purpose is to clear the compressibility effect and its impact of shock wave generation on the flow field and aerodynamics. Therefore, we perform a two-dimensional unsteady calculation by Computational fluid dynamics (CFD) analysis using the CLF5605 airfoil used in the Mars helicopter Ingenuity, which succeeded in its first flight on Mars. The calculation conditions are set to the Reynolds number (Re) at 75% rotor span in hovering (Re = 15,400), and the Mach number was varied from incompressible (M = 0.2) to transonic (M = 1.2). The compressible fluid dynamics solver FaSTAR developed by the Japan aerospace exploration agency (JAXA) is used, and calculations are performed under multiple conditions in which the Mach number and angle of attack (α) are swept. The results show that a flow field is similar to that in the Earth’s atmosphere above M = 1.0, such as bow shock at the leading edge, whereas multiple λ-type shock waves are observed over the separated shear layer above α = 3° at M = 0.80. However, no significant difference is found in the C<sub>p</sub> distribution around the airfoil between M = 0.6 and M = 0.8. From the results, it is found that multiple λ-type shock waves have no significant effect on the airfoil surface pressure distribution, the separated shear layer effect is dominant in the surface pressure change and aerodynamic characteristics.
文摘血液复苏是严重失血患者的关键急救措施。血液复苏液体的选用,经历了从全血到晶体液/胶体液、晶体液联合红细胞、等比例血液成分的演进过程。近20年来,采用低效价抗体O型全血(low titer group O whole blood,LTOWB)作为血液复苏的首选应急通用桥接复苏液,已发展成为大趋势。我们对全血在严重失血患者的应用历史和现状做一介绍,并提出我国采用LTOWB作为首选应急通用血液的进一步论证和验证研究建议。