Electrical and optical properties of nano aluminum film/particle structure

The electrical and optical effects of particles on the nano aluminum film deposited by thermal evaporation was investigated. From the characterization results of scanning electron microscope (SEM), the accumulation in tens of nanometers had been observed. The current-voltage (I-V) curve of the sample indicates its nonlinear electrical characters expecting the corresponding nonlinear optical properties. By the theoretical calculation, nonlinear conduction of the carrier transportation may result from the barrier-well-barrier structure, where negative resistance and Coulomb blockade effect appears. The simulation results are approximately matched with the experimental results. By testing the fluorescence emission spectrum of the sample, peaks were found to be located at 420 and 440 nm. In addition, the full width at half maximum (FWHM) had been obviously broadened by means of adding 2, 5-diphenyloxazole (DPO). Therefore, discrete energy levels could be estimated inside those particles.     

建筑端需求主导下的清水混凝土应用研究

分析了清水混凝土产业的发展前景,从性能要求、生产技术、施工与养护等方面概述了清水混凝土建筑的最新研究进展和技术要点,并结合上海保利大剧院的工程案例加以具体论证。提出了清水混凝土在房屋建筑工程中的应用创新理念,以期引导清水混凝土充分发挥性能优势,广泛应用于各种工程实践。     

考虑初期支护作用的引水隧洞衬砌结构配筋计算

我国水工高压隧洞设计规范中并未考虑围岩和初期支护的承载作用,往往使得最终的配筋量偏大,造成了不必要的浪费,并增加了施工难度.为此,结合某水电站引水隧洞,利用数值分析方法,模拟了隧洞施工全过程和初期支护的作用效果,分析了施加初期支护和不施加初期支护情况下的围岩稳定性,根据数值计算成果进行了衬砌结构配筋,并开展了裂缝开展宽...     

不同型式导流板对贴附通风性能的影响

为了探讨在相同条件下房间采用贴附送风加导流板通风方式时,导流板参数变化对室内工作区气流组织的影响,构建具有平面热源的房间,进行数值模拟研究。利用Fluent软件在非等温条件下探究导流板的角度、长度、安装高度对贴附射流气流组织的影响,分析不同形式的导流板对人员工作区流场均匀性、稳定性方面的差异及人员热舒适性的影响。结果显示:导流板与墙壁角度为100°时,气流在房间大部分区域形成场间循环,改变导流板角度不能明显改善头脚温差。长度更长的导流板带走房间余热的能力更强,与导流板长度10 cm、5 cm的房间相比,导流板长度为15 cm的房间工作区平均温度分别低0.4℃、1.2℃。导流板安装位置超过一定高度后,对室内气流组织的影响降低。研究结果为贴附送风加导流板通风方式提供参考。