对强化柴油机活塞的冷却油腔横截面形状和位置的作用的评价

<正> 将发动机的主要零件,特别是活塞的热负荷控制在适当的限度,是关系到柴油机单位面积功率不断增长的最迫切的任务之一。因此,广泛采用活塞顶部带有冷却油腔,并使冷却油在油腔内振荡以加强冷却具有极大的实际意义。     

车站对信息资源的综合应用

主要介绍了目前车站综合信息系统的组成及现状、完善车站综合信息系统的构想及其在强化运输安全管理、方便运输生产调度指挥、职工教育培训、车站办公自动化等方面的综合应用,为完善车站综合信息系统功能,充分发挥综合信息资源的作用提供了一定的参考价值.     

沥青改性性能与废旧胶粉的研究

从常规技术指标分析,硫化橡胶粉对沥青的高温性能、低温性能均有改善作用。要达到较好的改性效果需要足够数量的橡胶粉,一般15%～20%。使用橡胶粉不仅能够降低道路建设成本,也能有利于环境保护。但是胶粉的改性效果与SBS相比还有差距。     

盾构接收钢套筒内填料压力主动调控试验研究

The control of the pressure balance between the fillers in the steel sleeve and the ground is the key to ensuring the project's safety during receiving the shield with the steel sleeve in subway tunnelling. To realize the active regulation of the filling pressure in the steel sleeve, this study improves the fixed cover of a conventional steel sleeve to a piston cover that can slide freely along the longitudinal direction of the sleeve, and puts forward the corresponding methods for hydraulic pressure regulation and mechanical pressure regulation. The steel sleeve model is designed according to the 1∶5 ratio, and model tests are carried out for different working conditions, such as water injection with pressure increase, water release with pressure decrease, mechanical pressure increase under low levels of internal pressure, mechanical pressure increase and decrease under high levels of internal pressure, so as to study the variation pattern and influence mechanism of the filling pressure with the external hydraulic pressure and mechanical thrust, as well as the variation pattern of the jack counterforce and steel sleeve deformation. The results show that the filling pressure inside the steel sleeve varies linearly and proportionally to the external hydraulic pressure during hydraulic pressure regulation. Specifically, the increase of the mechanical pressure at lower filling pressures (≤0.15 MPa) shows multi-segment characteristics where the filling pressure changes to the variations in the jack pressure, while under the condition of high filling pressure (>0.15 MPa), the filling pressure varies steadily with the regulation process of the mechanical pressure. Both methods can achieve controlled active regulation of the filling pressure in the steel sleeve, and shall be chosen flexibly according to the characteristics of the regulation method, the construction ability, and the regulation's technical requirements. © 2023 Editorial By Modern Tunnelling Technology. All rights reserved.     

经济发展周期性波动中的人民生活质量

改革开放20多年，伴随经济的周期性发展，我国人民生活发生了巨大变化，已由温饱实现小康。     

水泥砼路面板破坏原因及防治

文章主要介绍了水泥砼路面病害分类,分析了水泥砼路面断板的原因,提出了病害预防措施和修复方法,对水泥砼路面施工、养护具一定指导意义。     

高速公路互通立交出口匝道安全评价

鉴于高速公路互通立交出口匝道交通事故频发的现状,分别采用基于公路安全评价指南和基于汽车行驶动力学的前、后两种方法对某高速公路出口匝道工程实例进行安全评价,然后对比前、后两种评价方法的异同,并分析基于交通心理学的速度感知误差对两种方法评价结果的影响。结果表明：相对于前者评价方法而言,后种评价方法的安全标准偏低;采用前者评价方法计算得到的互通立交出口匝道运行速度明显偏大,不满足行驶平衡的要求,即前者方法用于计算出口匝道的运行速度存在适应性问题;速度感知误差对后者评价方法判断结论的影响程度大于前者方法;出口匝道宜综合前、后两种方法进行安全评价。     

电动汽车用动力蓄电池回收利用标准化发展思路研究

动力蓄电池作为电动汽车的动力源,是影响电动汽车发展的核心部件。随着电动汽车在全球范围内迅速发展,蓄电池行业成为了最具投资潜力的产业。然而,蓄电池制造业对有色金属的需求量巨大,蓄电池从配料、生产开始,到流通使用、回收、处理、再生利用等全生命周期的各个环节都存在重金属污染的风险。目前蓄电池行业的现状是规模化企业少、中小企业多、特别是部分铅酸蓄电池企业技