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71.
Athanasios Eftaxias Josep Font Agusti Fortuny Azael Fabregat Frank Stüber 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(6):677-687
The wet air oxidation of phenol over a commercial active carbon catalyst was studied in a trickle bed reactor (TBR) in the temperature and oxygen partial pressure ranges of 120–160 °C and 0.1–0.2 MPa, respectively. The performance of the active carbon was compared in terms of phenol and COD destruction. The weight change of active carbon due to reaction was also measured. Finally, oxic phenol adsorption isotherms were assessed in batch conditions at 25, 125 and 160 °C. In order to use the conversion data obtained from the TBR for a kinetic study, special care was taken to check the kinetic control in the TBR experiments. Several kinetic models including power law or Langmuir–Hinshelwood expressions were considered to describe the catalytic oxidation of phenol over active carbon. The simple power law model with first order dependence on both phenol and oxygen concentration predicted satisfactorily the experimental data not only over the entire range of operating conditions studied, but also outside its validity range. Copyright © 2005 Society of Chemical Industry 相似文献
72.
Abstract This study deals with the modeling of air pollution in apartments from laboratory measurements of source strengths, using formaldehyde and Total Volatile Organic Compounds (TVOCs) as model pollutants. The sources in two test apartments were grouped into two: building-related sources and occupant-related sources. The measured source strengths and ventilation rates were used for the prediction of concentrations expected in the apartments. These predictions were compared to measurements in the apartment over 12 months. The conclusions were that the model predictions based on emission rates measured in the laboratory can be used to predict the long-term concentration of the two model pollutants in the apartments. Considering the measured differences in ventilation between the apartments, an occupant emission rate of between 0.2 and 0.3 mg/h/kg body weight could be estimated. Based on previous suggested limits of acceptable exposures of humans to VOCs, an acceptable average emission rate of VOCs from building materials in general was estimated to be about 30 (μ/m2/h. The modeling showed that during the first 200 days, building materials dominated the emissions. After this, sources relating to the occupants dominated. On average about half of the VOC pollution originated from the building materials. 相似文献
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74.
金属矿山深热矿井气温的预测计算是一个难题,本文探讨了应用灰色系统预测理论来解决这一难题的新途径,并通过实例验证了该方法的可行性和有效性。 相似文献
75.
徐云生 《昆明理工大学学报(自然科学版)》1996,21(6):21-25
基于太阳辐射的光变特性和多层薄膜材料的变色效应,分析了新型太阳能节能窗对热候,冷候和温候空调的工作原理,重点讨论了可实现外加参量的动态调节透光性的薄膜材料的性能。 相似文献
76.
Air entrainment in fresh concrete with PFA 总被引:6,自引:0,他引:6
D.S. Zhang 《Cement and Concrete Composites》1996,18(6):409-416
The results of a study into the influence of PFA on air entrainment in fresh concrete are discussed It is shown that the required dosage of AEA to produce an air content of 5.5 ± 0.5% in a PFA modified concrete mix is two-six times that required in the corresponding neat OPC concrete mix. The dosage of a vinsol based air entraining agent (AEA) required appears to be directly related to the PFA content of the mix. Similar direct relationships were obtained with a range of different PFAs. The dosage of an AEA based on the salt of a fatty acid appears to be sensitive to both PFA and OPC contents. For the type of PFA used, the variability of measured air content or the amount of air retained after continued agitation both indicated that vinsol based AEAs show the highest variability whilst fatty acid based AEAs show low variability. The between batch variability of air content was significantly improved by the addition of PFA regardless of the AEA used. 相似文献
77.
本文针对散热量大 ,散湿量小并要求控制室内相对湿度的场所进行了空调方案的分析比较 ,由此选择了一种比较节能和节省投资的空调设计方案。 相似文献
78.
在我国经济快速发展的大背景下,能源(水、电、油)的消耗在企业中所占的比重越来越高,也受到愈来愈大的重视。同时也由于房地产的快速发展需求,中央空调的市场需求呈现强劲的增长。在市场容量不断增大的吸引下,越来越多的厂家加入到商用中央空调的领域。变频技术应用于中央空调系统,对提升中央空调自动化水平、降低能耗.减少对电网的冲击,延长机械及管网的使用寿命,都具有重要的意义。 相似文献
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80.