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The effects of arbuscular mycorrhizal fungi (AMF) Glomus mosseae on the responses to elevated O3 in growth and nutrition of snap
bean (Phaseolus vulgaris L. cv Guangzhouyuan) were investigated. Exposure was conducted in growth chambers by using three O3
concentrations (20 (CF), 80 (CFO1) and 120 nL/L (CFO2); 8 hr/day for 75 days). Results showed that elevated O3 slightly impacted
overall mycorrhizal colonization, but significantly decreased the proportional frequency of hypha and increased the proportional
frequency of spores and vesicles, suggesting that O3 had significant effects on mycorrhizal structure. Elevated O3 significantly decreased
yield, dry mass and nutrient contents (N, P, K, Ca and Mg) in both non-mycorrhizal and mycorrhizal plants. However, significant
interactive effects were found in most variables due to that the reduction by O3 in the mycorrhizal plants was less than that in the
non-mycorrhizal plants. Additionally, AMF increased the concentrations of N, P, Ca, and Mg in shoot and root. It can be concluded
that AMF alleviated detrimental effects of increasing O3 on host plant through improving plant nutrition and growth. 相似文献
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The AgCl/Al2O3 catalyst has potential for use in the selective catalytic reduction (SCR) of NOx. A compound hydrocarbon, following
oxygenation is used as a type of reducing agent. In this experiment, the AgCl/Al2O3 catalyst was produced by four different methods,
and the differences among their reduction catalysis of NOx were compared. Ethanol was used as a type of reducing agent. X-ray
diffraction analysis was performed to study the crystalline structure and scanning electron microscope and transmission electron
microscope (TEM) were applied to determine the microindentation. The results indicated that, in the range of 350–400°C, there was
no significant difference on the NOx reduction rate; however, there was dispersion at high and low temperature ranges. The size of the
AgCl particles was about 20–100 nm. 相似文献
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为了了解过氧化氢与三维电极的协同作用,以罗丹明B模拟废水进行了实验研究,探索了填料配比、外加电压、过氧化氢投加量、初始废水pH值、染料初始浓度等单因子对降解罗丹明B的影响,并通过正交试验研究各因素对该法处理罗丹明B模拟废水的效应.结果表明,过氧化氢与三维电极在处理罗丹明B模拟废水时具有明显的协同作用;外加电压=20v,... 相似文献
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