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71.
The selective catalytic reduction (SCR) rate of NO with N-containing reducing agents can be enhanced considerably by converting part of NO into NO2. The enhanced reaction rate is more pronounced even at lower temperatures by using an equimolar mixture of NO and NO2 (fast SCR reaction). The oxidation characteristics of NO over catalyst Pt/TiO2 have been determined in a fixed bed reactor (8 mm-ID) with different concentrations of oxygen, nitric oxide and nitrogen dioxide in the presence of 8% water. The conversion of NO to NO2 increases with increasing oxygen (O2) concentration from 3 to 12%, but it levels off at higher O2 concentrations. The NO conversion to NO2 decreases with increasing NO concentration and it also decreases by an addition of NO2 in the feed stream. Therefore, the oxidation of NO over Pt/TiO2 catalyst could be auto-inhibited by the reaction product of NO2. The effects of CO and SO2 on NO oxidation characteristics have also been determined. In fact, the presence of SO2 significantly suppresses oxidation of NO but due to the less stability of sulfate on anatase structure in TiO2, it becomes less significant. On the other hand, the presence of CO increases NO oxidation significantly due to the auto-inhibition effect by CO. Moreover, the effect of SO2/CO on NO oxidation has also been determined and it was observed that NO oxidation decreases with the increase in SO2/CO ratio.  相似文献   
72.
Environmental Science and Pollution Research - Several plant species such as grasses are dominant in many habitats including arid and semi-arid areas. These species survive in these regions by...  相似文献   
73.
Environmental Science and Pollution Research - The instant endeavor was undertaken to monitor copper (Cu) contents in water, soil, forage, and cow’s blood impacted by heavy automobiles in...  相似文献   
74.
Environmental Science and Pollution Research - Smoking is considered as one of the major reasons behind genetic variations in cardiometabolic disorders. However, effect of nicotine via smoking on...  相似文献   
75.
Environmental Science and Pollution Research - Sunflower plants need nitrogen consistently and in higher amount for optimum growth and development. However, nitrogen use efficiency (NUE) of...  相似文献   
76.
77.
This study presents detailed analysis of spatiotemporal variations and trend of dust optical properties i.e., Aerosol Optical Depth(AOD) and Angstrom component over Asian desert regions using thirteen years of data(i.e., 2001–2013) retrieved from Aerosol Robotic Network(AERONET), Moderate Resolution Imaging Spectroradiometer(MODIS) and Multi-angle Imaging Spectroradiometer(MISR). These regions include Solar Village, Dunhuang and Dalangzadgad and are considered as origin of desert aerosols in Asia. Mann–Kendall trend test was used to show the trend of AOD. The relationship of AOD with weather parameters and general AOD trend over different wavelengths has also been shown. AOD's trend has been observed significant throughout the year in Solar Village, while in Dunhuang and Dalanzadgad the significant trend has been found only in peak period(March–June).Analysis show high values of AOD and low values of angstrom in Solar Village during peak period. In Chinese desert regions, high values of AOD have been found during peak period and low values in pre-peak period. Significant relationship has been observed between AOD and average temperature in Solar Village and Dalanzadgad whereas rainfall and wind speed showed no significant impact on AOD in all desert regions.  相似文献   
78.
The inhibitory efficiency of anionic copolymers and the effect of the biocides sodium hypochlorite, glutaraldehyde, and tris(hydroxymethyl)nitromethane on the precipitation behavior of calcium fluoride (CaF2) were studied. The efficiency of polymeric inhibitors was traced from conductivity measurements by using half-life (t1/2) method. X-ray diffraction parameters have been measured for calcium fluoride scale minerals. An anionic copolymer (K-798) acts as one of the best inhibitors for the precipitation process of the calcium fluoride in water as compared to K-775. It is assigned to the fact that the copolymer (K-798) contains both sulfonic acid and sulfonated styrene groups while the polymer (K-775) having only the sulfonic acid group. It was further observed that the biocides have no appreciable effect on the performance of the anionic polymeric inhibitors.  相似文献   
79.
Environment, Development and Sustainability - Environmental deterioration and global warming has created a substantial impact on international companies to incorporate eco-friendly, green supply...  相似文献   
80.
Environmental Science and Pollution Research - The use of sewage water as an irrigation source can be beneficial in agricultural practices, however, it may result in human health risks due to the...  相似文献   
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