水轮机组联接螺栓的工作状态对水轮机组的稳定运行起重要作用。该文根据预紧力施加准则,在一定范围内选择多组工况,研究分析不同预紧力作用下,水轮机顶盖结构的变形规律和联接螺栓的应力特性。结果表明:施加335 k N预紧力时,顶盖最大变...水轮机组联接螺栓的工作状态对水轮机组的稳定运行起重要作用。该文根据预紧力施加准则,在一定范围内选择多组工况,研究分析不同预紧力作用下,水轮机顶盖结构的变形规律和联接螺栓的应力特性。结果表明:施加335 k N预紧力时,顶盖最大变形为2.53 mm、内顶盖联接螺栓最大应力为91 MPa,施加945 k N预紧力时,顶盖最大变形为2.31 mm、内顶盖联接螺栓最大应力为238.5 MPa,螺栓应力均小于其承载极限;预紧力越大,则顶盖变形越小、螺栓承受应力越大,且螺栓的最大应力集中分布在其与顶盖法兰把合面附近。展开更多
The purpose of this study is to systematically showcase and evaluate how students’,schools’,and countries’Information and Communication Technology(ICT)development levels influence students’digital reading literacy...The purpose of this study is to systematically showcase and evaluate how students’,schools’,and countries’Information and Communication Technology(ICT)development levels influence students’digital reading literacy by using the data of the Program for International Student Assessment(PISA)2018 and the multi-level model approach.It is found that the ICT development at each level has a significant positive effect on students’digital reading literacy,and there is a significant interactive moderating effect between different levels.The gap in ICT development levels between the countries participating in the Belt and Road Initiative(BRI)and developed economies has a“Matthew effect”in widening the digital reading literacy gap in the short term,but in the long run,the faster growth of the countries participating in BRI in ICT development levels will narrow the gap and alleviate the effect.China should make use of its advantages in ICT development to engage in global education governance,facilitate the co-development in both the ICT development level and the digital reading literacy for the countries participating in BRI,and contribute to the development of global education by opening up a new way of development.展开更多
文摘水轮机组联接螺栓的工作状态对水轮机组的稳定运行起重要作用。该文根据预紧力施加准则,在一定范围内选择多组工况,研究分析不同预紧力作用下,水轮机顶盖结构的变形规律和联接螺栓的应力特性。结果表明:施加335 k N预紧力时,顶盖最大变形为2.53 mm、内顶盖联接螺栓最大应力为91 MPa,施加945 k N预紧力时,顶盖最大变形为2.31 mm、内顶盖联接螺栓最大应力为238.5 MPa,螺栓应力均小于其承载极限;预紧力越大,则顶盖变形越小、螺栓承受应力越大,且螺栓的最大应力集中分布在其与顶盖法兰把合面附近。
基金project“Studies on the Language Proficiency Standard and Development of English Teachers in Primary and Secondary Schools from the Perspective of Core Literacy”(No.17XYY029)supported by the National Social Science Fund of Chinaa part of the international and regional study funded by the Ministry of Education of the People’s Republic of China“The International Comparison of Primary and Secondary School Teachers’Status and Salaries and Strategies on How to Improve Them:Taking Poland,Finland,Germany,the United States,Japan,Republic of Korea,and China as Examples”(No.19GBQY027).
文摘The purpose of this study is to systematically showcase and evaluate how students’,schools’,and countries’Information and Communication Technology(ICT)development levels influence students’digital reading literacy by using the data of the Program for International Student Assessment(PISA)2018 and the multi-level model approach.It is found that the ICT development at each level has a significant positive effect on students’digital reading literacy,and there is a significant interactive moderating effect between different levels.The gap in ICT development levels between the countries participating in the Belt and Road Initiative(BRI)and developed economies has a“Matthew effect”in widening the digital reading literacy gap in the short term,but in the long run,the faster growth of the countries participating in BRI in ICT development levels will narrow the gap and alleviate the effect.China should make use of its advantages in ICT development to engage in global education governance,facilitate the co-development in both the ICT development level and the digital reading literacy for the countries participating in BRI,and contribute to the development of global education by opening up a new way of development.
