电梯防雷器件的应用

通过对雷电灾害和电梯防雷现状进行简单介绍．针对电梯控制系统应用电涌保护器件进行阐述．对有效防止雷击进行可行性分析。     

载人航天空间站舱内通风对流换热数值研究进展

CFD模拟是研究载人航天器舱内环境控制和地面模型试验验证的有效方法,介绍了国内外载人航天器舱内通风对流换热数值模拟的研究进展,目前的相关研究涉及舱内不同通风方式的数值模拟、通风参数的优化设计仿真、人体散热对通风环境的影响分析、舱内壁面温度分布和结露控制、微重力下通风换热问题的地面模型试验及其数值模拟验证、传热传质等诸多方面。指出数值模拟模型、舱内通风空调环境评定、通风空调系统整体优化、舱内环境数字仿真演示系统等是载人航天器舱内环境数值模拟领域值得进一步研究的问题。     

钢纤维混凝土隧道的耐久性能研究

大型土木工程结构中,材料的腐蚀对其结构耐久性具有很大的影响,因而正确分析和认识材料腐蚀的原因至关重要。尤其对于地铁隧道这种特殊地下工程的耐久性能更为重要,针对地铁隧道的杂散电流腐蚀问题,对钢纤维混凝土结构进行了杂散电流腐蚀试验,根据钢筋混凝土腐蚀破坏和钢纤维混凝土腐蚀破坏的等效原理,建立了钢纤维混凝土结构在杂散电流腐蚀作用下结构破坏的预测模型。     

拱坝坝肩岩体稳定地质力学模型试验

保证坝肩岩体稳定是拱坝设计和建设中的重要问题。由于岩体通常是非均匀、非弹性的不连续体,故其三维稳定性分析十分复杂。利用能反映地质构造特点的地质力学模型试验研究拱坝坝肩岩体稳定是一种较新的有效方法。本文论述了拱坝坝肩稳定的类型及性质、地质力学模型试验的原理和方法以及试验技术问题。文中并介绍了为国内一座大型重力拱坝进行的坝肩稳定三维小块体地质力学模型试验研究成果,分析了该坝左坝肩在水压超载条件下的破坏机理,指出它与通常采用的刚体极限平衡理论分析结果差异较大。     

带施香,消臭,杀菌功能的节能型家用空调器的研制

作者采用微机优化设计程序得出了空调器各部件参数，并经实验确定了各部件的匹配及有关的最佳参数，所研制的三种系列空调器能效比（ＥＥＲ）分别达到了３．２７，３．１４，３．４０。该空调器还具有独特的施香和紫外线杀菌功能。     

住宅钢结构构件的可靠性分析

通过对钢结构构件加工误差的调查,利用概率理论得到构件抗力的分布特征。编写JC法和蒙特卡罗模拟法程序,计算得到住宅钢结构构件的可靠指标,为以后住宅钢结构的可靠性研究提供依据。     

Efficient electricity production and simultaneously wastewater treatment via a high-performance photocatalytic fuel cell

A great quantity of wastewater were discharged into water body, causing serious environmental pollution. Meanwhile, the organic compounds in wastewater are important sources of energy. In this work, a high-performance short TiO₂ nanotube array (STNA) electrode was applied as photoanode material in a novel photocatalytic fuel cell (PFC) system for electricity production and simultaneously wastewater treatment. The results of current work demonstrate that various model compounds as well as real wastewater samples can be used as substrates for the PFC system. As a representative of model compounds, the acetic acid solution produces the highest cell performance with short-circuit current density 1.42 mA cm⁻², open-circuit voltage 1.48 V and maximum power density output 0.67 mW cm⁻². The STNA photoanode reveals obviously enhanced cell performance compared with TiO₂ nanoparticulate film electrode or other long nanotubes electrode. Moreover, the photoanode material, electrolyte concentration, pH of the initial solution, and cathode material were found to be important factors influencing the system performance of PFC. Therefore, the proposed fuel cell system provides a novel way of energy conversion and effective disposal mode of organics and serves well as a promising technology for wastewater treatment.     

Subsidies and welfare maximization tradeoffs in bus transit systems

Under a maximum welfare objective, a fixed route bus system and a flexible route bus system are optimized subject to various financial constraints. For each bus system, the decision variables including fare, headway, route spacing, and service zone area are optimally solved to analyze unconstrained, break-even and subsidy cases. Numerical results and sensitivity analysis are presented in the paper. From the numerical evaluation, it is shown that the effects of subsidies on welfare are quite different for a fixed route bus system versus a flexible route bus system. For the fixed route bus system, the optimal welfare curve is very flat over a wide range of subsidies. However, for the flexible route bus system, the break-even constraint causes a large loss in the social welfare. Thus, with the welfare maximization objective, the break-even policy or low transit subsidy policy may be preferable for the fixed route bus system, but not for the flexible route bus system. The results derived from this study can support effective decision-making on bus transit systems in areas that may experience significant shifts in residential density, as well as geographic or physical changes in their street networks. This paper was presented at the 46th annual meeting of Western Regional Science Association in Newport Beach, California, 21–24 February 2007.     

带构造柱双排孔混凝土空心砌块墙抗震性能试验研究

双排孔混凝土小型空心砌块中间孔洞较小无法设置芯柱,故设置构造柱是提高这种砌块建筑水平抗侧力性能的主要措施。为了研究这种结构体系的抗震性能,本文对7个设置构造柱双排孔混凝土空心砌块承重墙原型试件进行了低周反复荷载试验。得到了其承载力、延性和耗能等实测数据,并分析了墙片单元X形裂缝的破坏特征。试验及分析表明,双排孔混凝土小型空心砌块承重墙片在采用了约束构造柱等措施后,约束构造柱对墙体可起到有效约束作用,使破碎的墙体不倒塌,具有良好的抗震性能。     

砂浆试块采用底模的统一问题

用试验数据说明块采用不同的底模对砂浆块强度有较大的影响，指出现行有关标准对底模规定的不一致性。通过对试块砂浆强度涵义的阐述，说明各类体的砂浆，其试块底模作统一规定是必要的，合理的，并结合现状就底模的统一和当前应注意的问题提出了建议。