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991.
梁止水  邓琳  高海鹰  李宏卓  杨才千 《环境工程》2013,(Z1):124-127,183
为了研究合肥市南淝河底泥中总氮、总磷的污染状况,在南淝河及支流选取22个取样断面采集底泥柱状样,并分别利用碱性过硫酸钾消化紫外比色法和酸性过硫酸钾消化接钼锑抗比色法对总氮(TN)和总磷(TP)含量进行测定,并分析其空间分布规律。研究结果表明:南淝河底泥中氮、磷的含量随着深度的增加而减小,且总氮和总磷的各级断面上的含量与《全国河流湖泊水库底泥污染状况调查评价》研究报告中的数据相比,含量明显全国平均水平,属于生态危险区。  相似文献   
992.
We investigated the effect of calcium ion on the adsorption of humic acid (HA) (as a target pollutant) by powered activated carbon. The HA adsorption isotherms at different pH and kinetics of two different solutions including HA alone and HA doped Ca2+, were performed. It was showed that the adsorption capacity of powdered activated carbon (PAC) for HA was markedly enhanced when Ca2+ was doped into HA. Also, HA and Ca2+ taken as nitrate were tested on the uptake of each other respectively and it was showed that the adsorbed amounts of both of them were significantly promoted when HA and calcium co-existed. Furthermore, the adsorbed amount of HA slightly decreased with the increasing of Ca2+ concentration, whereas the amount of calcium increased with the increasing of HA concentration, but all above the amounts without addition. Finally, the change of pH before and after adsorption process is studied. In the two different solutions including HA alone and HA doped Ca2+, pH had a small rise, but the extent of pH of later solution was bigger.  相似文献   
993.
The decay of wood and other cellulosic materials by fungi cause significant economic loss. The widely used chromated copper arsenate was prohibited for the environmental impact and safety of arsenic and chromium. It was found that natural product hinokitiol (HK) had fungicidal and insecticidal activities, and its toxicity was bearable for the environment. We described the practical synthesis of HK-K salt. According to the GB/T18261-2000 and LY/T1283-1998, wood preservative performance of HK-K salt was tested. The results showed that the best inhibitory concentration of HK-K salt was 50 mg/L, for which the prevention effectiveness on mold is better, the killed value is between 0 and 1, and the corrosion-resistant for wood-rotting fungi is grade A.  相似文献   
994.
Porous S-doped bismuth vanadate with an olive-like morphology and its supported iron oxide (y wt.% FeOx/BiVO4-δS0.08, y = 0.06, 0.76, and 1.40) photocatalysts were fabricated using the dodecylamine-assisted alcohol-hydrothermal and incipient wetness impregnation methods, respectively. It is shown that the y wt.% FeOx/BiVO4-δS0.08 photocatalysts contained a monoclinic scheetlite BiVO4 phase with a porous olive-like morphology, a surface area of 8.8-9.2 m^2/g, and a bandgap energy of 2.38-2.42 eV. There was co-presence of surface Bi^5+, Bi^3+, V^5+, V^3+, Fe^3+, and Fe^2+ species in y wt.% FeOx/BiVO4-δS0.08. The 1.40 wt.% FeOx/BiVO4-δS0.08 sample performed the best for Methylene Blue degradation under visible-light illumination. The photocatalytic mechanism was also discussed. We believe that the sulfur and FeOx co-doping, higher oxygen adspecies concentration, and lower baudgap energy were responsible for the excellent visible-light-driven catalytic activity of 1.40 wt.% FeOx/BiVO4-δS0.08.  相似文献   
995.
分析我国具体国情,传统的以"高能耗、高物耗、高排放"为特征的高碳经济模式的弊端暴露无遗,必须予以摒弃,代之以"低排放、低消耗、低污染"为主要特征的低碳经济模式。政府应该在低碳经济发展中发挥重要作用,财政政策作为政府实现其职能调节整体经济发展的重要工具,在低碳经济发展中起着举足轻重的作用,政府财政政策的强力是推动低碳经济发展的必要条件。在此基础上具体分析了中国低碳经济发展的现状,指出中国发展低碳经济中财政政策方面存在的主要问题,并针对存在的问题提出几点建议,对于推动我国低碳经济发展和政府财政政策的完善具有重要意义。  相似文献   
996.
近年来随着机动车数量的增加,机动车尾气中含有大量的有毒有害气体,使得空气质量和人们的健康受到了严重威胁.  相似文献   
997.
人工增雨是指出了由于自然气象条件出现增雨之外,利用目前的气象情况和条件,通过人工干预的方式使得出现更多增雨的方法.本文首先分析了人工增雨的必要性,讨论了目前人工增雨工作存在的问题和作业过程中需要重视的问题,最后为我国人工增雨的未来发展提出了若干建议.  相似文献   
998.
Environmental Science and Pollution Research - In this paper, Delphi method was used to evaluate the low-carbon technologies and measures for high agricultural carbon productivity in Taihu Lake...  相似文献   
999.
Environmental Science and Pollution Research - The unequal cost and benefit led by environmental changes may potentially set China’s rural areas a “Poverty Trap.” Therefore,...  相似文献   
1000.
Environmental Science and Pollution Research - Butylated hydroxytoluene (BHT), one of the most widely used synthetic phenolic antioxidants, is a popular food additive. Previous studies have...  相似文献   
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