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31.
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
32.
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
33.
本文提出采用高分子有机材料配合,生产石膏制品防水防潮剂的生产方法和工艺。该剂还可以应用到氧化镁系列板材,同时提出开发珠光或彩色防水防潮剂,能达到满足的装饰效果,值提开发推广。 相似文献
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35.
A novel current source inverter system interconnected to the single‐phase grid is proposed. It has the same construction as the conventional three‐phase current source inverter that is interconnected to the single‐phase three‐wire distribution system. Though the proposed circuit has no output transformer, it can be equivalently performed as the single‐phase double cascade inverter by diverting the pole transformer in the utility system. By controlling the appropriate scheme, the output currents can be obtained as the five‐level waveforms and their distortions can be decreased sufficiently. It is applied to the interactive electric energy storage system with batteries and the basic discharging characteristics are discussed experimentally. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 150(2): 50–61, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10380 相似文献
36.
用浸渍法制备了一系列氧化锆担载的含稀土Ⅷ族金属催化剂,对其在二氧化碳甲烷化过程中的催化活性作了研究,并用漫反射紫外可见光谱,FTIR等手段对催化剂作了表征。结果表明,含稀土新型催化剂具有催化活性高,目标产物选择性好等优点;稀土主要以氧化物形式存在于催化剂表面,参与对氢及表面含碳物种的吸附及活化;含稀土三组份催化剂的活性与所添加稀土三价离子的4f电子数有关。 相似文献
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38.
未知钍—铀比的误差分析 总被引:6,自引:1,他引:5
研究了在任意Th、U含量和Th-U比覆盖整个范围(即0≤Th/U≤∝)时总α计数率对年剂量的转换因子及其误差。结果表明,当不测定Th-U比而只测量总α计数率时,最终引起的年龄误差对0≤Th/U≤∝来说为±5.1%-±8.3%,对1.1≤Th/U≤9.5来说只有±2.5%%-±4.1%。 相似文献
39.
THz source based on optical Cherenkov radiation 总被引:1,自引:0,他引:1
40.