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181.
182.
Pt/TiO2/ZSM-5在日光下氧化氨氮的研究   总被引:1,自引:0,他引:1  
采用溶胶-凝胶法和光沉积法制备了Pt/TiO2/ZSM-5催化剂。研究了铂修饰对催化剂的吸附性能的影响。考察了催化剂在日光照射下对氨氮的氧化,并以紫外光作为对比。结果表明铂的修饰,对催化剂的吸附能力有较大影响,还可以提高催化剂在日光照射条件下对氨氮的氧化效率和总氮去除率。在太阳光照射、空气曝气条件下,反应2h氨氮去除率达50.1%,总氮去除率达31.8%。  相似文献   
183.
太阳辐射对纯液体蒸发行为影响的实验研究   总被引:1,自引:0,他引:1  
通过蒸发实验,考察了太阳辐射对液体苯、甲苯和乙醇蒸发行为的影响.实验结果表明,苯和甲苯表面温度随时间呈现出先降低后升高的趋势,而乙醇则呈现出先降低后恒定的趋势,且环境风速越大,这种变化趋势就越明显.液体表面温度的变化不但与太阳辐射强度以及环境风速的大小有关,还与液体本身的物理性质(如热容、蒸发潜热和饱和蒸气压)有关.因此,在预测液体的蒸发速率时,必须考虑太阳辐射或周围热辐射源对液体表面温度的影响.  相似文献   
184.
Traditionally, the toxic effects of petroleum have been investigated by conducting studies in the absence of ultraviolet radiation (UV). Photomediated toxicity is often not considered, and the toxic effects of an oil spill can be grossly underestimated. The toxicity of a weathered oil collected from a monitoring well at an abandoned oil field toCeriodaphnia dubia was examined in the presence of UV. A solar simulator equipped with UVB, UVA, and cool white lamps was used to generate environmentally comparable solar radiation intensities.C. dubia were exposed to six concentrations of water accommodated fractions (WAF) of weathered oil in conjunction with three levels of laboratory simulated UV (Reference = < 0.002 μW/cm2UVB; 3.0 μW/cm2 UVA; Low = 0.30 μW/cm2 UVB; 75.0 μW/cm2 UVA; High = 2.0 μW/cm2 UVB; 340.0 μW/cm2 UVA) and visible light. Seven day static renewal bioassays were used to characterize WAF/UV toxicity. WAF toxicity significantly (p < 0.05) increased when the organisms were exposed to WAF in the presence of UV. The photoenhanced toxicity of the WAF increased with WAF concentration within each UV regime. Relative to the reference light regime, the average number of neonates from adults exposed to 1.6 mg TPH/L decreased significantly by 20% within the low light regime, and by 60% within the high light regime. These results indicate that organisms exposed to dissolved-phase weathered oil in the presence of environmentally realistic solar radiation, exhibit 1.3–2.5 times greater sensitivity, relative to organisms exposed under traditional laboratory fluorescent lighting.  相似文献   
185.
对自行研制的电子设备太阳辐射试验系统进行了介绍。设备研制中对试验系统的辐照灯阵进行了优化设计,同时根据环境试验要求,介绍了太阳辐射试验设备研制过程中所遇到的辐射光源选择及强度控制、光谱分布修正和光源启动系统等技术难点,并给出了解决途径。该试验系统研制成功,为考核装备的环境适应性和产品可靠性提供了科学的试验手段。  相似文献   
186.
Paech, Simon J., John R. Mecikalski, David M. Sumner, Chandra S. Pathak, Quinlong Wu, Shafiqul Islam, and Taiye Sangoyomi, 2009. A Calibrated, High‐Resolution GOES Satellite Solar Insolation Product for a Climatology of Florida Evapotranspiration. Journal of the American Water Resources Association (JAWRA) 45(6):1328‐1342. Abstract: Estimates of incoming solar radiation (insolation) from Geostationary Operational Environmental Satellite observations have been produced for the state of Florida over a 10‐year period (1995‐2004). These insolation estimates were developed into well‐calibrated half‐hourly and daily integrated solar insolation fields over the state at 2 km resolution, in addition to a 2‐week running minimum surface albedo product. Model results of the daily integrated insolation were compared with ground‐based pyranometers, and as a result, the entire dataset was calibrated. This calibration was accomplished through a three‐step process: (1) comparison with ground‐based pyranometer measurements on clear (noncloudy) reference days, (2) correcting for a bias related to cloudiness, and (3) deriving a monthly bias correction factor. Precalibration results indicated good model performance, with a station‐averaged model error of 2.2 MJ m?2/day (13%). Calibration reduced errors to 1.7 MJ m?2/day (10%), and also removed temporal‐related, seasonal‐related, and satellite sensor‐related biases. The calibrated insolation dataset will subsequently be used by state of Florida Water Management Districts to produce statewide, 2‐km resolution maps of estimated daily reference and potential evapotranspiration for water management‐related activities.  相似文献   
187.
Solar and wind are inexhaustible, abundant, environmentally friendly and freely available renewable energy sources. Integration of these two sources has always been a complex optimization problem which requires efficient planning, designing and control strategies. Many researchers have designed cost effective and efficient hybrid solar-wind energy systems by using various available software tools and optimization algorithms. With the advancement in artificial intelligence methods, various new optimization techniques have been developed in the last few decades. This paper presents state of the art optimization methods applied to hybrid renewable based energy systems. A brief introduction of each technique is presented along with papers published in different reputed journals. This article also reviews different power management, control strategies and multi-objective optimization methods used for hybrid wind-solar systems. A case study is presented to demonstrate the efficacy of some of the algorithms.  相似文献   
188.
Intensive R&D efforts made in solar photovoltaic area has enabled Si, GaAs, CdTe, and CIGS devices exhibiting nearly ideal efficiencies. However, cost incurred per unit energy does not allow them to qualify for alternate energy source besides environmental issues at production floors. Consequently, search is still continuing not only to reduce cost by improved efficiency, reduced materials cost, and simplified processing resulting in a cleaner and greener technology. Current successes in organic, dye-sensitized, and perovskite solar cells with efficiencies in 10–15% range raise concrete hope for evolving a low cost and green technology involving solution processable organic/inorganic compounds extendable to roll-to-roll production. The current status and future prospects of these three promising routes are reviewed here highlighting the possibility of an emerging alternate green energy source to supplement the conventional ones at commercial level.  相似文献   
189.
190.
(CdS)x/(ZnS)1–x nanoparticles were synthesized as a visible light-driven photocatalyst using the stepped microemulsion technique with a series of the ratio factors (x). The photocatalytic test results showed that (CdS)x/(ZnS)1-x with x = 0.8 had the highest photo-reactivity for H2 production from water under visible light. The composite (CdS)0.8/(ZnS)0.2 catalyst had a heterogeneous structure that exhibited a much greater photocatalytic hydrogen production activity than either pure CdS or the homogeneous Cd0.8Zn0.2S solid solution. ZnS deposition also was shown to largely improve the stability of CdS in the heterostructured CdS/ZnS catalyst. Thermal treatment of the catalyst, i.e., annealing (CdS)0.8/(ZnS)0.2 at 723 K, improved the crystallinity of the catalyst and increased its photocatalytic H2 production rate by more than 36 times. Deposition of Ru on the surface of the catalyst particles by in situ photo-deposition further increased the photo-H2 generation rate by 3 times. The photocatalyst of 0.5%Ru/CdS/ZnS achieved the highest H2 production activity, at a rate of 12650 μmol/g-h and with a light to hydrogen energy conversion efficiency of 6.5%.  相似文献   
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