Lighting for road tunnels: The influence of CCT of light sources on reaction time

Drivers’ visual performance is closely related to traffic safety in a real driving environment. In order to improve the traffic safety of road tunnel lighting, the effect of LED lighting on human visual performance was investigated using reaction time as a parameter. The experiment was performed with a scale model that can simulate a road tunnel lighting environment. Reaction times were measured under different values of luminance, correlated colour temperature (CCT), eccentricity, and contrast. The results show that visual performance can be improved by increasing the CCT of the light sources. The improvement of visual performance is greater in peripheral vision than that in foveal vision. The shortest reaction times were measured at a luminance level of 10 cd/m² and at a CCT of 5000 K. An appropriate luminance value with high CCT is recommended for tunnel lighting in interior and transition zones.     

一步法合成α-MnO2/β-MnO2催化剂及其对甲苯催化氧化的性能研究

采用水热法在不同pH条件下制备了一系列MnO₂基催化剂,通过XRD、SEM、N₂吸脱附等手段对其进行了表征,并评价了它们对甲苯催化氧化反应的催化活性。表征结果表明,不同的pH本质上改变了s反应溶液的初始H⁺浓度,从而影响了所得样品的结晶环境,并赋予它们不同的晶相。甲苯的催化氧化评价结果表明,催化剂的催化性能与α-MnO₂的含量密切相关。当pH=11时所得到的MnO₂-11催化剂,具有最大的比表面积和最多的缺陷结构,使其具有最佳的催化活性（T₅₀=245℃和T₉₀=256℃）和优异的循环稳定性。     

动物修复技术对城市景观水体的修复研究

本实验采用野外自然放养的方法,研究景观金鱼及家鸭对富营养化水体的净化作用,定期采集水样并检测水体指标。研究结果表明:景观金鱼及家鸭对富营养化水体均有一定净化效果,水体中的TP、TN、叶绿素a都大幅度下降,水体透明度提高,水体生态功能得到初步恢复;其中金鱼对富营养化水体的综合处理效果最好,其对TN的处理效果达到63.6%,对TP的处理效果达到78.7%,对chla的处理效果达到88.7%。     

小型液体除湿空调系统实验研究

对小型液体除湿空调系统,从居住建筑除湿负荷及经济性角度出发,采用CaCl2溶液进行液体除湿实验,研究CaCl2除湿和再生的动态特性。研究发现除湿与再生的3个重要因素为溶液温度、溶液浓度和空气进口含湿量。在实验工况下,CaCl2溶液的除湿量为3.32 g/kg,再生性能优于除湿性能,约为除湿的1.3-2.9倍。对实验进行总结后,认为CaCl2作为除湿剂进行液体除湿还有很大改进空间和推广潜力。     

城市污水处理厂全过程生命周期评价模式探讨

LCA技术是科学确定污水处理工艺方案的一种有效手段。运用LCA技术,以污水处理工艺设施为主线,将城市污水处理厂的全过程生命周期分为3个阶段：施工建设阶段、生产运行阶段和报废拆除阶段,并结合LCA的基本框架对污水处理厂的全过程生命周期进行了分析。该生命周期评价模式不仅考虑了环境因素,而且考虑了技术和经济因素。通过具体实例的分析,对所提评价模式进行论证,评价出两种不同污水处理工艺方案的优劣。     

天然气加热炉的热力计算与分析

通过对天然气加热炉的工作原理及炉内传热过程的分析,确立了天然气加热炉的热力计算方法,并编制了Excel组件对其进行计算、通过计算,从设计的角度对影响天然气加热炉热效率的主要因素,如过量空气系数、负荷率及烟管管径等进行了分析．     

CFD simulation of VOCs concentrations in a resident building with new carpet under different ventilation strategies

This paper investigates the effect of ventilation strategies on the concentrations of volatile organic compounds (VOCs) emitted from a new carpet in an apartment with the VOCs emission characteristics taken from chamber test data. The commercial software FLUENT 6 has been employed to solve the continuity, momentum, turbulence and concentration equations under five different ventilation strategies. Numerical results show that ventilation strategies have a small effect on VOCs emission from carpet. Continuous ventilation keeps a low level of VOCs concentration in the air. Flushing ventilation has a significant effect on the VOCs concentration in the air. During a period without ventilation, VOCs concentration in the air usually increases to a high level. Thus, the ventilation should be carried out before the arrival of residents to ensure a low level of VOCs concentration. At the startup of ventilation run, the sudden flow strongly promotes the mixing of VOCs, which may lead to local high concentration.     

重庆地区居住建筑遮阳构筑物对建筑能耗的影响

太阳辐射对供暖、空调负荷有重要的影响,而窗口的遮阳是改善住宅能耗的一个重要措施.以单位面积建筑能耗作为衡量遮阳效果的指标,结合重庆当地气候特征,分析了Low-E玻璃和水平遮阳板的遮阳性能对建筑能耗的影响.并在综合考虑冬、夏节能不同需求的基础上,给出了适合重庆地区使用的Low-E节能玻璃和水平遮阳板的设置方式.     

光聚合壳聚糖基絮凝剂及其絮凝性能

壳聚糖是一种天然碱性氨基多糖物质,其分子上分布着许多功能性的氨基和羟基,使其能成为潜在的高效絮凝剂。采用紫外光引发壳聚糖(CS)与丙烯酰胺(AM)、丙烯酰氧乙基三甲基氯化铵(DAC)接枝共聚制备P(CS-AD)絮凝剂,探讨了单体浓度、壳聚糖百分比、阳离子度、光引发剂浓度、光照时间对P(CS-AD)的特性粘度的影响,确定了合成的优化条件:单体浓度为30%~40%、壳聚糖百分比为10%~20%、阳离子度为30%~40%、光引发剂浓度为0.3%~0.5%、光照时间为120min,优化后的制备的P(CS-AD)的特性粘度最高可达1 865mg/L。同时,采用红外光谱、扫描电镜(SEM)、差热热重分析(TG-DTA)对其进行表征。采用模拟硅藻土水样验证其絮凝性能,试验结果表明:P(CS-AD)的絮凝性能显著优于市售聚丙烯酰胺(PAM)。     

Second-law analysis of aquifer thermal energy storage systems

The application of exergy (second-law) analysis to aquifer thermal energy storage (ATES) systems is investigated in order to facilitate proper assessments of overall system performances. An elementary ATES model is created, and the corresponding expressions are developed for efficiencies and for the quantities of energy and exergy that are injected and recovered. It is demonstrated that ATES performance measures based on exergy often are more useful and meaningful than those based on energy. Exergy efficiencies account for the temperatures associated with energy transfers to and from an ATES, as well as the quantities of energy transferred, and consequently provide a measure of how nearly ATES systems approach ideal thermodynamic performance. Energy efficiencies do not provide a measure of approach to ideal performance and, in fact, are often misleadingly high because some of the energy recovered can be at too low a temperature to be available for a useful purpose.