桥联茂金属催化剂及其性能研究进展

介绍了桥联茂金属催化剂的发展、分类以及它的高立体选择性、高定向性等性能。讨论了桥联茂金属催化剂以及对相关产物立构规整性的影响,并对其应用前景做出展望。     

怀疑主义的实践可行性问题新探

怀疑主义的重大困难是其实践可行性问题,即怀疑主义者能否在生活中贯彻其怀疑主义。其实,怀疑主义的实践可行性问题的实质就是悬搁判断与信念的相容性,因此,从信念产生的角度是能够解决怀疑主义的实践可行性难题的。     

白俄罗斯皮划艇协会与国际皮划艇联合会体育仲裁案例评述

通过对2016年白俄罗斯皮划艇协会与国际皮划艇联合会体育仲裁案例的分析,得出研究结论：禁用药物超长的代谢时间不能成为反兴奋剂规则具有溯及力的理由;虽然《世界反兴奋剂条例》第11条的规定因为存在"集体项目"这一前提而没有违反个人责任原则,但该条第12条由于规定得过于简单仍然违反了该原则;国家司法机关刑事诉讼程序中发现的兴奋剂药物证据,在刑事诉讼程序终止而证据未经质证的情况下,不能直接作为兴奋剂违规行为的认定证据。     

应急性线上教学实践探索——以四川大学《老年医学》课程为例

2020 年突如其来的新型冠状病毒肺炎疫情影响了学校正常的教学计划,传统的“面授教学”未能如期开展。一时间“停课不停学”成为疫情期间教育界的主旋律,应急性线上教学也成为疫情期间的常态化教学方式。应急性线上教学不同于传统远程线上教学,在有限的准备时间和资源条件下,如何顺利开展应急性线上教学并保障学习成效是值得探索的课题。分析应急性线上教学特性,给出应急性线上教学的几种策略,并以《老年医学》课程为例进行实践。通过对整个学期开展线上教学情况的梳理,验证应急性线上教学策略的可行性,可为今后应对突发情况下的线上教学提供参考。     

Three-dimensional nonlinear flutter analysis of long-span suspension bridges during erection

ＩＮＴＲＯＤＵＣＴＩＯＮＩｔｈａｓｂｅｅｎｒｅｃｏｇｎｉｚｅｄｔｈａｔｌｏｎｇ ｓｐａｎｂｒｉｄｇ ｅｓ ,ｃａｂｌｅ ｓｕｐｐｏｒｔｅｄｂｒｉｄｇｅｓｉｎｐａｒｔｉｃｕｌａｒ,ａｒｅｓｕｂｊｅｃｔｔｏｔｈｅｄｙｎａｍｉｃｗｉｎｄａｃｔｉｏｎ .Ｔｈｅａｅｒｏｄｙ ｎａｍｉｃｓｔａｂｉｌｉｔｙ (ｆｌｕｔｔｅｒ)ｏｆｓｕｓｐｅｎｓｉｏｎｂｒｉｄｇｅｓｄｕｒｉｎｇｅｒｅｃｔｉｏｎｉｓａｓｕｂｊｅｃｔｏｆｍａｊｏｒｃｏｎｃｅｒｎｆｏｒｒｅｓｅａｒｃｈｅｒｓａｎｄｅｎｇｉｎｅｅｒｓ .Ａｌｔｈｏｕｇｈｔｈｅｐｅｒｉ…     

Design optimization on the front wheel orientation parameters of a vehicle

1. Introduction In order to improve the driving operation performance, the front suspension of a vehicle is generally of McPherson independent style, which can simplify the structure, lighten the unsprung mass, and conveniently arrange the engine and steering system. Moreover, it can adapt to many types of springs and is of advantage to adjust the height of the vehicle. In such a system, the axis of the kingpin is the line between the upper damper end and the intersection of the transverse ar…     

悬挑式外脚手架应用分析

当施工条件不允许搭设落地式外脚手架时,经过计算采用悬挑式外脚手架,缩短了工期,满足了业主的要求.     

“I Didn't Do Nothin'”: The Discursive Construction of School Suspension

This article examines the issue of school suspension by looking at the sociocultural factors that influence a teacher's decision to remove a student from the classroom. The authors use ethnographic and discourse analytic approaches to study how disciplinary moments are constructed by teachers and students in an urban high school in the Midwest. The analysis of classroom observations, videotaped lessons, and interviews from a longitudinal study at this multiethnic high school shows that suspensions frequently occur in the absence of any physical violence or blatant verbal abuse. Rather, suspensions are often preceded by a complex series of nonviolent events when one disruptive act among many is singled out for action by the teacher. This study has implications for current debates about zero-tolerance policies that disproportionately affect students of color for their misbehavior in school. Our analysis suggests that removing a student from class is a highly contextualized decision based on subtle race and gender relations that cannot be adequately addressed in school discipline policies.     

由公路桥梁的主要样式浅议我国公路桥梁的发展

改革开放以来,我国的公共事业取得了巨大的发展,特别是公路建设事业取得了巨大的进步。但由于我国的复杂的地理特征,公路修建的过程中,很多地方需要建设公路桥梁,公路桥梁可以说是我国公路建设中的重要组成部分,一般公路、高级公路上的立交桥,跨海、跨河大桥都得到了较快的发展。公路桥梁样式多样、功能各异、各有千秋,已建成的一座座桥梁是我国公路事业发展史上的一座座丰碑。本文作者就公路桥梁的主要样式,简要谈一下我国公路桥梁的发展。