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41.
Environmental Science and Pollution Research - In the process of water treatment, excessive nitrogen and phosphorus pollutants are of great concern. Therefore, we prepared nanoscale zerovalent iron...  相似文献   
42.
Environmental Science and Pollution Research - The fiscal decentralization system under China’s political centralization affects local economic and environmental policies, and thus has an...  相似文献   
43.
Environmental Science and Pollution Research - The high NO2/NOX ratio in the after-treatment system is beneficial to its performance and achieved by NO catalytic conversion in diesel oxidation...  相似文献   
44.
Environment, Development and Sustainability - Textiles release microfibers to the environment during production, use, and at end-of-life disposal. There is a potentially large and growing risk to...  相似文献   
45.
Environmental Science and Pollution Research - The impact of soil lead (Pb) pollution on survival, growth, and reproduction of the collembolan, Folsomia candida, and Pb compartmentation in its gut...  相似文献   
46.
The paper focuses on studying the conversion of rice husks and sawdust into liquid fuel. Rice husks, sawdust and their mixture are pyrolyzed at temperatures between 420 and 540 degrees C, and the main product of liquid fuel is obtained. The experimental result shows that the yield of liquid fuel depends on various factors such as feedstock and temperature. The maximum yields for rice husks, sawdust and their mixture are 56%, 61% and 60% at 465, 490 and 475 degrees C, respectively. Analyses with GC-MS and other apparatus show that the liquid fuel is a complicated compound with low caloric value and can be directly used as a fuel oil for combustion in a boiler or a furnace without any upgrading. Alternatively, the fuel can be refined to be used by vehicles.  相似文献   
47.
Wang  Jiaqing  Lu  Pei  Su  Wei  Xing  Yi  Li  Rui  Li  Yuran  Zhu  Tingyu  Yue  Huifang  Cui  Yongkang 《Environmental science and pollution research international》2019,26(20):20248-20263

Currently, activated coke is widely used in the removal of multiple pollutants from industrial flue gas. In this paper, a series of novel FexLayOz/AC catalysts was prepared by the incipient wetness impregnation for NH3-SCR denitrification reaction. The introduction of Fe-La bimetal oxides significantly improved the denitrification performance of activated coke at mid-high temperature, and 4% Fe0.3La0.7O1.5/AC exhibited a superior NOx conversion efficiency of 90.1% at 400 °C. The catalysts were further characterized by BET, SEM, XRD, Raman, EPR, XPS, FTIR, NH3-TPD, H2-TPR, et al., whose results showed that the perovskite-type oxide of LaFeO3 and oxygen vacancies were produced on the catalysts’ surfaces during roasting. Fe-La doping enhanced the amount of acid sites (mainly Lewis and other stronger acid sites) and the content of multifarious oxygen species, which were beneficial for NOx removal at mid-high temperature. Moreover, it was investigated that the effect of released CO from activated coke at mid-high temperature on the NOx removal through the lifetime test, in which it was found that a large amount of CO produced by pyrolysis of activated coke could promote the NOx removal, and long-term escaping of CO on the activated coke carrier did not have a significant negative impact on catalytic performance. The results of the TG-IR test showed that volatile matter is released from the activated coke while TG results showed that the weight loss rate of 4% Fe0.3La0.7O1.5/AC only was 0.0015~0.007%/min at 300–400 °C. Hence, 4% Fe0.3La0.7O1.5/AC had excellent thermal stability and denitrification performance to be continuously used at mid-high temperature. Finally, the mechanisms were proposed on the basis of experiments and characterization results.

  相似文献   
48.
To investigate the effects of humic acids (HAs) on the ability of plants to defend themselves against oxidative stress, barley was hydroponically cultured in the absence and presence of HAs, and the antioxidant enzymatic activities (catalase, superoxide dismutase, ascorbate and glutathione peroxidases) of root tissue were evaluated. Auxin-like structures in HAs, which were extracted from an oxidation product of lignite (LHA) and compost derived from cattle manure (CHA), were identified by pyrolysis-gas chromatography/mass spectrometry (GC/MS) with tetramethylammonium hydroxide. The LHA, which had the lower molecular weight, was more effective in promoting the growth of barley root than CHA. However, the amounts of auxin-like structures in the CHA were much higher than those for LHA. The antioxidant enzymatic activities were initially decreased in the presence of LHA and CHA at the first day after refreshing the culture solution, but were significantly increased on the second day. The CHA sample, which contained relatively high levels of phenolic acids that contained auxin-like structures, was effective in increasing four types of enzymatic activities, while the activities of catalase and ascorbate peroxidase were increased in the presence of LHA, which contains naphthalene derivatives. These results indicate that using HAs as a supplement can be effective in enhancing antioxidation enzymatic activities, while the appearance of the effects is retarded because of the decomposition and release of auxin-like compounds from HAs by organic acids from the plant roots.  相似文献   
49.
50.
苯蒸气在有机膨润土上的吸附动力学   总被引:4,自引:0,他引:4  
本文研究了苯蒸气在溴化十六烷基三甲基胺(CTMAB)系列单阳离子有机膨润土上的吸附动力学过程。结果表明,苯蒸气在有机膨润土上的吸附符合一级动力学方程,即:r=KvCo;在12h内,吸附反应均可达到平衡,吸附速率常数(Kv)与温度(T)成正相关,吸附反应的活化能在9.50-17.92kJ.mol^-1之间。  相似文献   
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