Results 31 to 40 of about 23,545 (152)
Jianzhu Gangjiegou Jinzhan轮载下正交异性钢桥面板的局部效应显著，相邻各疲劳易损细节的疲劳行为相互影响，特别是随着某个细节裂纹扩展，相邻细节疲劳应力可能增大，桥面板疲劳性能呈加速劣化趋势。疲劳应力响应及桥面板性能劣化评估已成为钢桥面板运营期面临的挑战和亟待进行的工作。为合理评估开裂正交异性钢桥面板的疲劳性能演化情况，基于既有足尺模型疲劳试验，综合采用有限元程序ANSYS和Franc3D的多尺度交互技术模拟钢桥面板典型疲劳易损细节裂纹扩展行为，探究裂纹扩展过程中各关键细节（顶板与U肋连接焊缝、U肋与横隔板连接焊缝、横隔板开孔处 ...
叶华文 +4 more
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Guangtongxin yanjiu, 1998 本文报道了平面结构正面进光高速ＧａＩｎＡｓ／ＩｎＰ平面ＰＩＮ光电二极管（使用Ｓｉ－ＩｎＰ衬底）。该器件具有高的稳定性（在１５０℃下经１４４０小时高温老化后，暗电流无变化），大带宽（１５ＧＨｚ），高响应度（在１．３μｍ波长下，响应度为０．９４Ａ／Ｗ）。
徐之韬, 王任凡, 陈浩瀚
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International Journal of Applied Linguistics, EarlyView.ABSTRACT This study examines how foreign language teachers’ beliefs about the medium of instruction and translanguaging evolve over time by revisiting three in‐service teachers twelve years after their initial interviews. Using a qualitative longitudinal design, the study traces how translanguaging was initially framed as pedagogically deficient but ...
Danping Wang
wiley +1 more source
Jianzhu Gangjiegou Jinzhan, 2022 对湛江新机场航站楼屋盖结构的屋面风荷载特性和时域法风振响应特性进行研究，分别采用分区风振系数法、分区多目标法和分区约束多目标法计算屋盖结构的等效静风荷载。结果表明：屋盖表面平均风压主要表现为负压，在垂直于风向角的屋盖迎风前缘负压最大，距离迎风前缘越远风压逐渐减小，脉动风压变化规律与平均风压基本相同。屋盖结构最大风振响应处主要位于屋面悬挑区域，结构设计时需重点关注该区域的响应。分区风振系数法等效风压分布合理，但等效响应整体误差大。以少量分区脉动风压为荷载基本向量的分区多目标法等效响应整体精度高 ...
区彤, 张佳武, 陈进于, 冯若强
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International Journal of Applied Linguistics, EarlyView.ABSTRACT With the increasing number of Chinese international students in Australian universities, intercultural competence has become a critical factor influencing their interactions with Australian tutors in university classroom settings. Existing research often examines students’ intercultural competence from a single‐method or single‐perspective ...
Jiangyu Han, Linda Tsung
wiley +1 more source
International Journal of Applied Linguistics, EarlyView.ABSTRACT In this study, control–value theory (CVT) was used to investigate how students’ perceptions of the classroom environment shape their anxiety in the context of English as a foreign language (EFL) learning through the mediating effects of control and intrinsic value appraisals.
Quan Qian, Xianhan Huang
wiley +1 more source
四川大学学报. 自然科学版, 1998 应用１．５级反应的热动力学时间变量法，研究了阳、阴、非、两性离子表面活性剂胶束溶液中ＮａＨＳＯ３为单组分引发剂的丙烯酰胺聚合反应．结果表明，离子型（ＣＴＡＢ，ＴＴＡＢ，ＤＴＡＢ，ＳＤＳ）和两性型表面活性剂（ＳＬＳ）对该聚合反应有催化作用，非离子型表面活性剂（Ｂｒｉｊ３５）对该反应有微弱禁阻作用．这些作用是由于表面活性剂影响了引发剂生成自由基的反应，与胶束Ｓｔｅｒｎ层对ＨＳＯ－３的影响有关，而与胶束内部结构无关．
陈民助 +5 more
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Zhejiang Daxue xuebao. Lixue ban, 2014 近年来，在纳米尺度的研究中应用到很多表面的技术和概念.然而，以往针对表面的研究中对象为单晶块体样品，这些研究结果将不再适用纳米材料.为了研究表面对纳米体系弹性响应的影响，选取较为简单的铜纳米薄片为研究对象，构建了铜(111)面和(001)面的薄片模型，使用第一性原理方法计算了铜纳米薄片的双轴泊松比，分析了纳米薄片与体材料的差异，研究不同厚度纳米薄片中表面对内层原子的影响.计算结果显示，表面原子层的双轴泊松比大于内部原子层，并且其收敛速度和数值大小均和薄片取向有关.根据双轴泊松比随厚度的变化特性 ...
WANGXueqiang(王学强) +3 more
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Vocabulary Strategy Instruction in the Argentine EFL Context: Teachers’ Perspectives and Practices
International Journal of Applied Linguistics, EarlyView.ABSTRACT Despite extensive research on vocabulary strategy instruction (VSI), little has been known about teachers’ perspectives on how it is understood and implemented in practice. This study investigated Argentinian EFL teachers’ priorities in vocabulary instruction, their perceived knowledge of learner strategies for spoken vocabulary, and factors ...
Isobel Kai‐Hui Wang, Andrew D. Cohen
wiley +1 more source
Jianzhu Gangjiegou Jinzhan钢-混凝土组合梁桥在满足使用性能的同时也会发生疲劳损伤，在桥梁设计和使用阶段应保证桥梁不发生疲劳破坏。为研究不同因素对桥梁疲劳损伤的影响，选取一座双工字钢-混凝土组合连续梁桥，采用车桥耦合分析程序对不同的车速、车重、桥面不平整度、桥面板厚度和主梁腹板高度下主梁的疲劳损伤进行分析。首先计算不同影响因素下桥梁的动应力，分析应力幅和等效应力幅个数的变化规律；然后分析应力幅冲击系数随各影响因素的变化规律；最后分析不同影响因素下主梁疲劳细节位置的疲劳损伤。研究结果表明：车重 ...
李喜梅, 章建成, 母渤海
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