铒单离子磁体(C18H23Er)器件的自旋极化输运

研究单分子磁体的自旋极化输运性质。搭建由扫描隧道显微镜钴针尖、铒单离子磁体以及金（111）衬底所构成的分子器件模型。在小偏压下,计算铒单离子磁体在正立和倒立2种构型下的自旋极化电流曲线,发现此单分子磁体器件的隧穿磁电阻最高达120%,自旋过滤效率在70%~100%。对比2种构型下的整流比,发现倒立构型有较大的整流比。通过分析体系的透射谱、分子投影哈密顿量、器件投影态密度等,对上述物理效应的根源进行解释。     

将军山隧道光面爆破技术与参数的选择

应用正台阶法开挖方法和微差、光面爆破技术,对将军山隧道掘进施工,通过合理选择爆破参数,减少了爆破对围岩的扰动,提高了隧道围岩的稳定性,控制了超欠挖量,加快了掘进速度,取得了理想的爆破效果。     

注塑模中隧道滑块的设计

定模隧道滑块和动模隧道滑块在现今的模具设计中越来越常见,其设计特点是该制品的外观更加美观,滑块成型面积不大,更多运用于复杂和多变的塑料产品形状和塑料模具设计.     

下河坝岩溶公路隧道施工技术分析

岩溶隧道施工因其工程地质和水文地质的复杂和特殊而异常困难。文章结合金沙江溪洛渡水电站对外交通专用公路下河坝隧道施工实践,试图探索隧道岩溶及岩溶水的处理途径和高压富水岩溶隧道的施工技术。     

岳英山水库除险加固工程设计

本文首先介绍了岳英山水库的概况,分析了工程现状。针对水库除险加固的主体工程即坝体工程、溢洪道和输水洞设计,从主坝坝坡整修、副坝迎水坡放缓及护坡、坝基防渗溢洪道和输水洞等方面进行了探讨。     

海底公路隧道照明智能调控系统施工技术探讨

通过厦门东通道(翔安隧道)工程隧道照明工程的实施,阐述了隧道照明智能调控系统原理,有效制定了施工方案,并根据海底公路隧道特点对施工控制要点进行了分析总结,操作简便,并降低管理成本,在满足安全行车的同时,使照明效果更加舒适和美观。     

铁路隧道软弱围岩施工对策探讨

针对铁路隧道施工中软弱围岩的自稳性能较差的问题,介绍了软弱围岩的力学特点,分析了软弱围岩的支护结构作用机理,相应地提出了提高软弱围岩稳定性的施工对策,可供同类地质施工工程参考。     

Fluid forces on kayak paddle blades of different design

Three kayak paddle blades of different design (Conventional, Norwegian, Turbo) were tested in a low-speed wind tunnel at a maximum chord Reynolds number of Re = 2.2–2.7 × 10⁵ (corresponding to speed through water of ≈1 m/s). The mean drag force and side force acting on each blade were measured, as the yaw and pitch angles were varied. The results were compared with those recorded for a finite rectangular flat plate of similar area and aspect ratio. For zero pitch angle of the blades, the results indicate that the drag coefficient was mostly independent of the blade design as the yaw angle was varied between ± 20°, with only the Norwegian blade design displaying a marginally higher drag coefficient than either of the other two blades or the flat plate. Increasing the pitch angle to 30°, while maintaining the yaw angle at zero, resulted in a 23% reduction of the drag coefficient for the flat plate, but only a 15% reduction of the drag coefficients for the three blades. For all designs, the drag coefficient reduction followed a simple cosine relationship as the pitch angle or yaw angle was increased. The wind tunnel experiments revealed that the side force coefficients for all three paddle blade designs were entirely independent of the blade design and were indistinguishable from those recorded for a flat plate. In summary, the study showed that the nondimensional force coefficients are largely independent of the paddle blade design.     

文新1号隧道进口浅埋段施工方案研究

本文研究了文新1号隧道进口浅埋段施工方案.首先介绍了工程概况,对该工程的施工方案进行了概述,进一步根据该工程的隧道环境和水文地质条件,提出了洞口防护加固施工方案和隧道进洞施工方案,为后续的施工奠定基础,并为类似的工程施工提供指导.     

基于风洞试验的帆翼空气动力性能研究

利用风洞试验进行帆板的空气动力参数是研究风帆性能的重要手段,本文概述了帆翼的空气动力性能的几个特征指标、帆翼模型、试验的方法、风洞试验的控制条件等;并对拱度试验、风向角0°～360°帆翼空气动力性能的试验、帆的前倾、后倾、正扣、反扣七种组合的对比试验结果进行了分析、对帆设计、操作以及航速预测均具有较大的指导作用。