PURPOSE: To observe the effects of acupuncture on the pituitary-thyroid axis in rabbits with fracture. METHOD: 36 male rabbits with a 3-mm width experimental defect in the middle segment of the left radius were random...PURPOSE: To observe the effects of acupuncture on the pituitary-thyroid axis in rabbits with fracture. METHOD: 36 male rabbits with a 3-mm width experimental defect in the middle segment of the left radius were randomly divided into the treatment group and control group, and the changes in serum T3, T4 and TSH contents in different weeks were investigated. RESULTS: Serum T3, T4 and TSH contents in the treatment group all were higher than those in the control group, with statistically significant differences in the contents of T4 and TSH in the second week and T3 content in the fourth week (P展开更多
As one of the vital steps in the 3rd phase of China＇s lunar exploration program （CLEP）, the circumlunar return and reentry spacecraft, developed by China Academy of Space Technology （CAST）, is used to demonstrate...As one of the vital steps in the 3rd phase of China＇s lunar exploration program （CLEP）, the circumlunar return and reentry spacecraft, developed by China Academy of Space Technology （CAST）, is used to demonstrate the key technologies of by- per-speed return and reentry spacecraft. The system configuration and flight process are presented in this paper, as well as the analysis of mission characteristics, the key technologies and the technical advancement during the R＆D progress. The significance of circumlunar return and reentry spacecraft is given at the end.展开更多
The head of nuclear pressure vessel is a key component to guarantee the safety of nuclear power plant, so it is necessary to improve its mechanical properties during manufacturing. In the practical production,due to t...The head of nuclear pressure vessel is a key component to guarantee the safety of nuclear power plant, so it is necessary to improve its mechanical properties during manufacturing. In the practical production,due to the huge size of the ingots from which the head is manufactured, coarse grains and voids are common defects existing in the material. Furthermore, cracks may appear in the forming process. It is highly demanded that the forming process must be properly designed with suitable parameters to compact the voids, to refine and homogenize the grains and to avoid cracks. Therefore, the research on the evolution of internal voids, grain size and cracks is very important to determine the forming process of huge components. SA508-3 steel is the material to manufacture the head of pressure vessel in the nuclear island. In the previous studies, we have separately built models to evaluate the evolution of internal voids, grain size and cracks during the hot forming process for SA508-3 steel. This study integrates the models for multi-scale simulation of the forging process of the head of nuclear pressure vessel in order to control the quality of the forgings. Through the software development, the models are integrated with a commercial finite element code DEFORM. Then, the extended forging and final forging processes of the head are investigated, and some appropriate deformation parameters are recommended.展开更多
文摘PURPOSE: To observe the effects of acupuncture on the pituitary-thyroid axis in rabbits with fracture. METHOD: 36 male rabbits with a 3-mm width experimental defect in the middle segment of the left radius were randomly divided into the treatment group and control group, and the changes in serum T3, T4 and TSH contents in different weeks were investigated. RESULTS: Serum T3, T4 and TSH contents in the treatment group all were higher than those in the control group, with statistically significant differences in the contents of T4 and TSH in the second week and T3 content in the fourth week (P
基金The Major Special Projects on National MediumLong-term Science and Technology Development Planning
文摘As one of the vital steps in the 3rd phase of China＇s lunar exploration program （CLEP）, the circumlunar return and reentry spacecraft, developed by China Academy of Space Technology （CAST）, is used to demonstrate the key technologies of by- per-speed return and reentry spacecraft. The system configuration and flight process are presented in this paper, as well as the analysis of mission characteristics, the key technologies and the technical advancement during the R＆D progress. The significance of circumlunar return and reentry spacecraft is given at the end.
基金the National Science and Technology Major Project of China(No.2012ZX04012-011)the National Natural Science Foundation of China(No.51675335)
文摘The head of nuclear pressure vessel is a key component to guarantee the safety of nuclear power plant, so it is necessary to improve its mechanical properties during manufacturing. In the practical production,due to the huge size of the ingots from which the head is manufactured, coarse grains and voids are common defects existing in the material. Furthermore, cracks may appear in the forming process. It is highly demanded that the forming process must be properly designed with suitable parameters to compact the voids, to refine and homogenize the grains and to avoid cracks. Therefore, the research on the evolution of internal voids, grain size and cracks is very important to determine the forming process of huge components. SA508-3 steel is the material to manufacture the head of pressure vessel in the nuclear island. In the previous studies, we have separately built models to evaluate the evolution of internal voids, grain size and cracks during the hot forming process for SA508-3 steel. This study integrates the models for multi-scale simulation of the forging process of the head of nuclear pressure vessel in order to control the quality of the forgings. Through the software development, the models are integrated with a commercial finite element code DEFORM. Then, the extended forging and final forging processes of the head are investigated, and some appropriate deformation parameters are recommended.
