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In an urban-transit bus,fueled by biodiesel in Toledo,Ohio,single inhalable particle samples in October 2008 were collected and detected by scanning electron microscopy and energy dispersive X-ray spectrometry(SEM/EDS).Particle size analysis found bimodal distribution at 0.2 and 0.5 μm.The particle morphology was characterized by 14 different shape clusters:square,pentagon,hexagon,heptagon,octagon,nonagon,decagon,agglomerate,sphere,triangle,oblong,strip,line or stick,and unknown,by quantitative order.The square particles were common in the samples.Round and triangle particles are more,and pentagon,hexagon,heptagon,octagon,nonagon,decagon,strip,line or sticks are less.Agglomerate particles were found in abundance.The surface of most particles was coarse with a fractal edge that can provide a suitable chemical reaction bed in the polluted atmospheric environment.The three sorts of surface patterns of squares were smooth,semi-smooth,and coarse.The three sorts of square surface patterns represented the morphological characteristics of single inhalable particles in the air inside the bus in Toledo.The size and shape distribution results were compared to those obtained for a bus using ultra low sulfur diesel. 相似文献
146.
The possibility of amending Pb 2+ contaminated soil (S) with paper sludge (P) was investigated through adsorption and desorption experiments. The adsorption process of Pb 2+ in soil containing paper sludge (SP) could be well described by pseudo second-order kinetic model and the Langmuir isotherm model. After P addition, the equilibrium time decreased greatly (from 28 to 8 hr) and the Pb 2+ maximum adsorbed amount (Q max ) increased by a factor of more than three to 102.04 mg/g. Q max reached its maximum as... 相似文献
147.
以长安地裂缝带黄土为研究对象,通过采取裂缝面上的黄土及未受裂缝影响的原状黄土进行电镜扫描试验,对两者的微观结构特征进行了对比研究,并分析了裂缝带附近黄土物理力学性质变异的原因。结果表明:裂缝面黄土与原状黄土在微观结构上存在显著差别,主要表现为裂缝面黄土颗粒接触类型为面-面接触,具有定向排列现象,颗粒之间孔隙较小、结构致密,并可见明显的擦痕,原状黄土颗粒接触类型则表现为棱-面接触或面-面接触,并发育缝隙状孔隙,总体为镶嵌孔隙结构;两者微观结构的差异表明地裂缝的活动具有剪切滑移特征。 相似文献
148.
-PbO2 electrodes were prepared by electro-deposition and characterized by scanning electron microscopy, X-ray diffraction, X-ray
photoelectron spectroscopy, and linear sweep voltammetry. We confirmed pure -PbO2 crystals were on the electrode and it had a high
oxygen evolution potential. The photoactivity and photoelectrochemical (PEC) properties of the -PbO2 electrode were investigated
under visible light irradiation ( > 420 nm) for the decolorization of Methylene Blue. Pseudo first-order kinetics parameter (Kapp) for
dye decolorization using the -PbO2 electrode achieved 6.71×10?4 min?1 under visible light irradiation, which indicated its excellent
visible light-induced photoactivity. The Kapp of the PEC process was as much as 1.41×10?3 min?1 and was 1.71 times that of visible light
irradiation or electrolysis even in the presence of the -PbO2 electrode. A significant synergetic effect was observed in the PEC system.
We also employed TiO2 modified -PbO2 electrodes in this test, which revealed that the TiO2 immobilized on the -PbO2 electrode
inhibited the visible light-induced PEC efficiency despite the amount of TiO2 used for electrode preparation. The -PbO2 electrode was
also superior to the dimensionally stable anode (Ti/Ru0:3Ti0:7O2) in visible light-induced photoactivity and PEC efficiency. 相似文献
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Oon Lee Kang Nazaruddin Ramli Mamot Sai Musa Ahm Suhaimi Md Yasir Arbakariya Ariff 《环境科学学报(英文版)》2011,23(6):918-922
The Cr(III) sorption experiments onto Kappaphycus alvarezii waste biomass were conducted at different pH values (2–6) under the
conditions of initial metal concentration of 10–50 mg/L and the chemical compositions of Cr-Cu and Cr-Cd. The Cr(III) sorption
capacities were slightly dependent on pH, and the maximum sorption capacity was 0.86 mg/g at pH 3. The sorption capacities
increased with increase in the initial metal concentration, whereas it was suppressed by the presence of Cu(II) and Cd(III) in the
solution. The Cr(III) sorption equilibrium was evaluated using Langmuir, Freundlich and BET isotherms. The sorption mechanisms
were characterised using scanning electron microscopy and Fourier transform infrared spectroscopy. The main mechanisms were ion
exchange coupled with a complexation mechanism. Kappaphycus alvarezii waste biomass represents a potential for Cr(III) ion removal
from aqueous solution. 相似文献
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