排序方式: 共有37条查询结果,搜索用时 15 毫秒
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16 构件 16.1 旁承 在普通货车转向架上装配车体时,车体基本上是均衡地放在心盘上,上心盘允许在枕梁和摇枕间相对横向振动.当转向架在心盘支承上转动以通过曲线轨道时,旁承(图24)组件通过限制这种相对摇摆运动,来对车体起横向稳定作用. 相似文献
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尽管屡见报端的新闻确实使人们看到汽车业发生了格局混乱的现象,但是在汽车设计研发方面的技术创新却从未间断过。有很多技术创新的成果你已经能在最新的车型上看到了,不仅如此,未来还将有更多的新技术成果源源呈现在你的面前。 相似文献
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The built environment,walking, and physical activity: Is the environment more important to some people than others? 总被引:1,自引:0,他引:1
Ann Forsyth J. Michael Oakes Brian Lee Kathryn H. Schmitz 《Transportation Research Part D: Transport and Environment》2009,14(1):42-49
We examine whether specific types of people are more sensitive to the built environment when making a decision to walk or engage in other physical activity. Over 700 participants from 36 environmentally diverse, but equivalent-sized neighborhoods or focus areas responded to a survey, kept a travel diary, and wore an accelerometer for seven days. Subgroups defined by demographic and socioeconomic variables, as well as self reported health and weight status demonstrate that most subgroups of people walk more for transportation in high density areas. However, only the less healthy walked more overall in high density areas after controlling for sociodemographic characteristics and physical activity was remarkably similar among the groups and across different kinds of environments. While environmental interventions may not increase physical activity population wide, some populations – including some for whom interventions may be important such as the less healthy and the unemployed or retired – are more affected by these neighborhood environmental characteristics. 相似文献
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高温和中毒导致的催化剂活性丧失对催化剂性能有显著的影响,由于温度和中毒的作用,催化剂的物理化学特性产生了巨大的变化,催化剂性能的恶化与这种变化有关。催化剂的配方和设计应尽可能考虑催化剂对中毒和高温度的耐久性。 相似文献
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