低噪声沥青路面的应用研究

随着人们对城市道路交通噪声的不断重视,低噪声沥青路面应用成为环保城市建设的趋势。该文介绍了北京市京通快速路北辅路中国传媒大学段铺筑的低噪声沥青路面示范工程的研究,包括路面结构及排水设计、原材料要求、配合比设计和效果评价。检测结果表明该低噪声沥青路面示范工程具有较好的降噪效果,且渗水性和抗滑性等其它功能良好。     

环氧沥青水泥混凝土防水粘结层施工技术研究

该文介绍了环氧沥青防水材料的广阔应用前景,从施工工艺流程、施工质量控制要点等方面探讨了环氧沥青水泥混凝土防水粘结层的施工技术。     

土工合成材料及其在道路路基加固中的应用探讨

土工合成材料是以人工聚合物为原料制成的土工产品,是岩土工程中应用的合成材料的总称,也是当今岩土工程领域中被广泛采用的一种建筑材料,在道路工程中被广泛地应用于道路路基处理。该文针对土工合成材料的分类、特性、应用情况、设计计算进行了探讨与阐述。     

空气悬浮离心鼓风机在污水处理厂中的应用

鼓风机是曝气处理工艺污水处理厂中的关键设备。该文结合工程实例,介绍了空气悬浮鼓风机在污水处理厂中的应用前景。     

Effect of the number of fuel injector holes on characteristics of combustion and emissions in a diesel engine

The diesel combustion process is highly dependent on fuel injection parameters, and understanding fuel spray development is essential for proper control of the process. One of the critical factors for controlling the rate of mixing of fuel and air is the number of injector holes in a diesel engine. This study was intended to explore the behavior of the formation of spray mixtures, combustion, and emissions as a function of the number of injector hole changes; from this work, we propose an optimal number of holes for superior emissions and engine performance in diesel engine applications. The results show that increasing the number of holes significantly influences evaporation, atomization, and combustion. However, when the number of holes exceeds a certain threshold, there is an adverse effect on combustion and emissions due to a lack of the air entrainment required for the achievement of a stoichiometric mixture.     

中重型商用车发动机进排气系统的测试与匹配性研究

利用计算机作为通信和指令控制的上位机,组建了一套进排气系统多点压力、温度的自动采集和记录测试系统。使用该测试系统,对不同类型的发动机进排气组件进行了匹配性研究,经过系统的压力、温度对比试验,针对具体一款发动机找到最佳的进排气组件,有效地改善了发动机的经济性、动力性和排放性能。同时该测试方法作为一种技术手段为发动机匹配性的设计与优化提供了客观、量化的试验数据。     

基于仿真冲突的高速公路交通事件限速值研究

利用微观交通仿真软件Vissim和SSAM交通冲突分析模型,结合某一双向4车道高速公路,建立了交通事件下的高速公路仿真模型。分析了事件下的交通冲突特性,采用交通冲突数、交通冲突时间、平均排队长度等指标,研究了事件下不同限速方案对交通运行的影响,得到了事件下的优化限速值。     

Effects of systemic domestic recombinant human erythropoietin on HIF-1α expression in the retina in a rabbit model of acute high intraocular pressure

Objective To observe the expression of hypoxia inducible faetor-1α (HIF-1α) in the retina of rabbits with acute high intraocular pressure and to investigate the mechanism of systemic domestic recombinant human erythropoietin (rhEPO) protecting the retina from ischemia-reperfusion injury. Methods First, control group and model group were established in rabbit eyes. The acute high intraocular pressure model was established by saline perfusion into anterior chamber, and then hypodermic injection of domestic rhEPO was made. HIF-1α protein in the retina was observed by immunohistochemical staining method on days 1, 3, 7 and 14 after retinal ischemla-reperfusion, respectively. Results No cells with HIF-la positive expression were observed in the retina of the control group. Ceils with HIF-1α positive expression in the model group outnumbered those in the control group (P < 0. 01). The resemblance pattern occurred in EPO group but its degree was slightly greater than that in the model group from day 3 after ischemia-reperfusion (P<0.05). Conclusion Domestic rhEPO can down-regulate the expression of HIF-1α in the retina with acute high intraocular pressure, which may be one of the mechanisms that rhEPO protects the retina from ischemia-reperfusion injury.     

苏通大桥南桥塔中、下塔柱施工

苏通大桥南桥塔采用倒Y形塔, 中、下塔柱采用不对称的单箱单室箱形断面,施工中需克服塔柱斜率大、悬臂高等不利因素,且高塔施工受风力影响大,对施工平台及模板系统要求较高.采用液压自动爬模系统结合水平横撑的主动力顶撑的施工方法.实践表明:该施工方法能够提高塔柱施工效率, 缩短塔身施工周期,降低施工成本,保证混凝土的外观质量.     

现场静载试验加载系统设计与应用

采用内力等效原则,设计了板的集中力加载方案。为解决现场静载试验中人工堆载方法加栽精度差、耗时长、安全性差等问题,对加载系统改进设计。结果表明,该系统可明显提高试验效率,降低试验成本。