A fixed-geometry two-dimensional mixed-compression supersonic inlet with sweep-forward high-light and bleed slot in an inverted ＂X＂-form layout was tested in a wind tunnel. Results indicate： （1） with increases of...A fixed-geometry two-dimensional mixed-compression supersonic inlet with sweep-forward high-light and bleed slot in an inverted ＂X＂-form layout was tested in a wind tunnel. Results indicate： （1） with increases of the free stream Mach number, the total pressure recovery decreases, while the mass flow ratio increases to the maximum at the design point and then decreases; （2） when the angle of attack, a, is less than 6°, the total pressure recovery of both side inlets tends to decrease, but, on the lee side inlet, its values are higher than those on the windward side inlet, and the mass flow ratio on lee side inlet increases first and then falls, while on the windward side it keeps declining slowly with the sum of mass flow on both sides remaining almost constant; （3） with the attack angle, a, rising from 6° to 9°, both total pressure recovery and mass flow ratio on the lee side inlet fall quickly, but on the windward side inlet can be observed decreases in the total pressure recovery and increases in the mass flow ratio; （4） by comparing the velocity and back pressure characterristics of the inlet with a bleed slot to those of the inlet without, it stands to reason that the existence of a bleed slot has not only widened the steady working range of inlet, but also made an enormous improvement in its performance at high Mach numbers. Besides, this paper also presents an example to show how this type of inlet is designed.展开更多
In the screening tests of drugs for silicosis in our laboratory, we found that TT, a type of alkaloid isolated from Stephania tetrandra, could inhibit the development of experimental silicosis of rats and the synthesi...In the screening tests of drugs for silicosis in our laboratory, we found that TT, a type of alkaloid isolated from Stephania tetrandra, could inhibit the development of experimental silicosis of rats and the synthesis of collagen in rat lung. Chest X-rays of silicotic patients treaied with TT for 1-3 years showed obvious changes. The silicotic nodules became smallel and shadows became clearer. PVNO was proved to have anti-silicotic effect on animal and clinically. This presentation reports the effect of them on collagen mRNA.Dot blot results showed that 1 (Ⅰ) and 1 (Ⅲ) mRNA levels increased significantly at 60 and 120 days after the rats were exposed to silica dust. The mRNA levels went down at 1 and 3 months after treated by TT and PVNO. In situ hybridization observation revealed that the silver grains of Type Ⅰand Type Ⅲ collagen were scattered within the fibroblasts in cellular nodules and in thickened interstitium of silicosis tissue. The amounts of mRNA silver grains decreased in the lung tissue treated by TT and PVNO. It was suggested that TT and PVNO may inhibil the gene expression of collagen during silicosis展开更多
文摘A fixed-geometry two-dimensional mixed-compression supersonic inlet with sweep-forward high-light and bleed slot in an inverted ＂X＂-form layout was tested in a wind tunnel. Results indicate： （1） with increases of the free stream Mach number, the total pressure recovery decreases, while the mass flow ratio increases to the maximum at the design point and then decreases; （2） when the angle of attack, a, is less than 6°, the total pressure recovery of both side inlets tends to decrease, but, on the lee side inlet, its values are higher than those on the windward side inlet, and the mass flow ratio on lee side inlet increases first and then falls, while on the windward side it keeps declining slowly with the sum of mass flow on both sides remaining almost constant; （3） with the attack angle, a, rising from 6° to 9°, both total pressure recovery and mass flow ratio on the lee side inlet fall quickly, but on the windward side inlet can be observed decreases in the total pressure recovery and increases in the mass flow ratio; （4） by comparing the velocity and back pressure characterristics of the inlet with a bleed slot to those of the inlet without, it stands to reason that the existence of a bleed slot has not only widened the steady working range of inlet, but also made an enormous improvement in its performance at high Mach numbers. Besides, this paper also presents an example to show how this type of inlet is designed.
文摘In the screening tests of drugs for silicosis in our laboratory, we found that TT, a type of alkaloid isolated from Stephania tetrandra, could inhibit the development of experimental silicosis of rats and the synthesis of collagen in rat lung. Chest X-rays of silicotic patients treaied with TT for 1-3 years showed obvious changes. The silicotic nodules became smallel and shadows became clearer. PVNO was proved to have anti-silicotic effect on animal and clinically. This presentation reports the effect of them on collagen mRNA.Dot blot results showed that 1 (Ⅰ) and 1 (Ⅲ) mRNA levels increased significantly at 60 and 120 days after the rats were exposed to silica dust. The mRNA levels went down at 1 and 3 months after treated by TT and PVNO. In situ hybridization observation revealed that the silver grains of Type Ⅰand Type Ⅲ collagen were scattered within the fibroblasts in cellular nodules and in thickened interstitium of silicosis tissue. The amounts of mRNA silver grains decreased in the lung tissue treated by TT and PVNO. It was suggested that TT and PVNO may inhibil the gene expression of collagen during silicosis
