Stray grains,the most serious casting defect,mainly occur in the platform because of the abrupt transition of the cross-section in the directional solidification of superalloy single-crystal blades.A new mould baffle ...Stray grains,the most serious casting defect,mainly occur in the platform because of the abrupt transition of the cross-section in the directional solidification of superalloy single-crystal blades.A new mould baffle technology based on 3D printing and gelcasting is proposed herein to reduce the formation of stray grains in the platform.The influence of the proposed mould baffle technology on the temperature field in the platform during solidification was investigated by simulation and experiment.The numerical simulation results indicate that the proposed mould baffle technology can effectively hinder the radiation and heat dissipation at the platform extremities,and therefore,reduce undercooling in the platform and the formation of stray grains during directional solidification.Casting trials of a hollow turbine blade were conducted using CMSX-4 superalloy.The trial results demonstrate the potential of the proposed approach for manufacturing single-crystal superalloy blades.展开更多
Objective:This study sheds light on the going-out behaviors of patients with chronic diseases when purchasing drugs during COVID-19,explores what factors influence these behaviors,and makes recommendations to guarante...Objective:This study sheds light on the going-out behaviors of patients with chronic diseases when purchasing drugs during COVID-19,explores what factors influence these behaviors,and makes recommendations to guarantee the pharmaceutical treatment of patients with chronic diseases.Methods:A questionnaire based on the health belief model(HBM)was designed and convenience sampling was employed to administer the online questionnaires.The influence of the respondents’demographic information on their going-out behaviors was analyzed by means of multiple linear regression.A structural equation model(SEM)was constructed to explore how health beliefs related to chronic diseases and COVID-19 influenced patients’going-out behaviors.Results:A total of 869 questionnaires were analyzed.The structural equation model revealed that while the severity of the chronic disease had a direct positive effect on going-out behaviors(l=0.106),chronic disease behavior barriers had a direct negative effect on their going-out behaviors(l=-0.204).Conclusion:Educational background,co-living situation,and income could influence patients’going-out behaviors.The severity of the chronic disease and chronic disease behavior barriers directly affected patients’going-out behaviors.Furthermore,patients’health beliefs about COVID-19 ultimately affected their going-out behaviors by influencing their health beliefs related to chronic disease.展开更多
Infertility is one of the common gynecological diseases,and the incidence has been on the rise in recent years,and according to WHO,infertility will become the third most serious disease after tumor and cardiovascular...Infertility is one of the common gynecological diseases,and the incidence has been on the rise in recent years,and according to WHO,infertility will become the third most serious disease after tumor and cardiovascular disease in the 21st century.Food therapy and medicine in China has a long history,Sun Simiao Valuable Prescriptions for emergencies:"If you can use food to calm the disease,release the emotions and dispel the disease,can be said to be good workers",which is also an important embodiment of the Chinese medicine"cure the disease"idea.With the improvement of the living standard of Chinese residents in recent years,food therapy and medicinal food have become popular as a new treatment method because of its efficacy and ease of acceptance.The author summarizes and summarizes the research results of Chinese medicine and medicinal food in the treatment of infertility in recent years in order to provide reference for clinical treatment of infertility.展开更多
基金the Industry-University Research Cooperation Project of Aero Engine Corporation of China(Grant No.HFZL2019CXY023)the National Science and Technology Major Project(Grant No.2017-Ⅶ-0008-0101)。
文摘Stray grains,the most serious casting defect,mainly occur in the platform because of the abrupt transition of the cross-section in the directional solidification of superalloy single-crystal blades.A new mould baffle technology based on 3D printing and gelcasting is proposed herein to reduce the formation of stray grains in the platform.The influence of the proposed mould baffle technology on the temperature field in the platform during solidification was investigated by simulation and experiment.The numerical simulation results indicate that the proposed mould baffle technology can effectively hinder the radiation and heat dissipation at the platform extremities,and therefore,reduce undercooling in the platform and the formation of stray grains during directional solidification.Casting trials of a hollow turbine blade were conducted using CMSX-4 superalloy.The trial results demonstrate the potential of the proposed approach for manufacturing single-crystal superalloy blades.
文摘Objective:This study sheds light on the going-out behaviors of patients with chronic diseases when purchasing drugs during COVID-19,explores what factors influence these behaviors,and makes recommendations to guarantee the pharmaceutical treatment of patients with chronic diseases.Methods:A questionnaire based on the health belief model(HBM)was designed and convenience sampling was employed to administer the online questionnaires.The influence of the respondents’demographic information on their going-out behaviors was analyzed by means of multiple linear regression.A structural equation model(SEM)was constructed to explore how health beliefs related to chronic diseases and COVID-19 influenced patients’going-out behaviors.Results:A total of 869 questionnaires were analyzed.The structural equation model revealed that while the severity of the chronic disease had a direct positive effect on going-out behaviors(l=0.106),chronic disease behavior barriers had a direct negative effect on their going-out behaviors(l=-0.204).Conclusion:Educational background,co-living situation,and income could influence patients’going-out behaviors.The severity of the chronic disease and chronic disease behavior barriers directly affected patients’going-out behaviors.Furthermore,patients’health beliefs about COVID-19 ultimately affected their going-out behaviors by influencing their health beliefs related to chronic disease.
文摘Infertility is one of the common gynecological diseases,and the incidence has been on the rise in recent years,and according to WHO,infertility will become the third most serious disease after tumor and cardiovascular disease in the 21st century.Food therapy and medicine in China has a long history,Sun Simiao Valuable Prescriptions for emergencies:"If you can use food to calm the disease,release the emotions and dispel the disease,can be said to be good workers",which is also an important embodiment of the Chinese medicine"cure the disease"idea.With the improvement of the living standard of Chinese residents in recent years,food therapy and medicinal food have become popular as a new treatment method because of its efficacy and ease of acceptance.The author summarizes and summarizes the research results of Chinese medicine and medicinal food in the treatment of infertility in recent years in order to provide reference for clinical treatment of infertility.
