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铁炭-混凝沉淀-生化处理强酸性染料废水的中试研究 总被引:1,自引:0,他引:1
采用铁炭-混凝沉淀-水解酸化-生物接触氧化工艺对强酸性染料废水进行中试处理研究。在铁炭微电解单元主要考察了铁炭比、HRT和曝气量大小对处理效果的影响;在水解酸化单元主要考察了进水pH和HRT对处理效果的影响。通过铁炭微电解和水解酸化,在大幅改善废水的可生化性的同时,还可以有效去除废水的色度、削减有机负荷,以保证后续的生物接触氧化工艺的高效稳定运行。在生物接触氧化单元主要考察了进水浓度、HRT对处理效果的影响。经过组合工艺的处理,最终的出水COD〈75 mg/L,出水色度〈40倍。 相似文献
955.
研究了pH、初始浓度、时间及温度对甲基红在壳聚糖上吸附富集的影响。结果表明,pH是影响甲基红吸附富集的重要因素,最佳pH3.4。其动力学行为更好地符合Lagergren准二级反应动力学模型,随着温度增加,平衡吸附量减少。吸附过程的表观活化能(Ea)为7.518kJ/mol。壳聚糖对甲基红的吸附过程较好地符合Freundlich吸附等温方程。计算得到吸附过程的热力学参数△G0、△H0。和△S0分别为-24.88kJ/mol(303K)、-22.15kJ/mol和8.783J/(mol·K),表明壳聚糖对甲基红的吸附是一个自发的放热过程。红外光谱分析得到,壳聚糖吸附甲基红的过程中,壳聚糖分子中存在的大量羟基和氨基发挥了主要作用。 相似文献
956.
The study was undertaken to evaluate the effects of malathion and chlorpyrifos on acetylcholinesterase (AChE), esterase (EST) activity and antioxidant system after topical application with different concentration to Oxya chinensis. The results showed that malathion and chlorpyrifos inhibited EST, AChE activity and increased malondialdehyde (MDA) contents. A change in superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), glutathione peroxidase (GPx), and glutathione reductase (GR) activity combined with reduced glutathione (GSH) and total glutathione (tGSH) contents was found in O. chinensis after malathion and chlorpyrifos treatments. Malathion and chlorpyrifos increased SOD and CAT activity compared with the control. With the concentrations increasing, SOD and CAT activity showed the similar tendency, namely, SOD and CAT activity increased at the lower concentrations and decreased at the higher concentrations. The results showed that malathion and chlorpyrifos decreased significantly GR activity. GST and GPx activity at the studied concentrations of chlorpyrifos was lower than that of the control. However, no significance was observed. GPx and GST activity in malathion treated grasshoppers showed a biphasic response with an initial increase followed by a decline in its activity. Malathion and chlorpyrifos decreased GSH contents and the ratio of GSH/GSSG. The present findings indicated that the toxicity of malathion and chlorpyrifos might be associated with oxidative stress. 相似文献
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Liting Yang Chunlan Dai Lijun Ma Shaoquan Lin 《Journal of Polymers and the Environment》2011,19(1):189-195
The conjugated soybean oil was synthesized through the isomerization reaction of soybean oil to transformed the structure
of linoleic acid into conjugated linoleic acid structure, and Rhodium complexes (RhCl(Pph3)3) was used as catalyst. The efficiency on the conjugation of catalyst RhCl (Pph3)3, tin dichloride dehydrate (SnCl2·2H2O) and triphenylphosphine (Pph3) were evaluated. The results showed when RhCl(Pph3)3, SnCl2·2H2O and Pph3 are 9.25, 9.0 and 13.1 mg in 100 g soybean oil respectively, the highest conversion of conjugation achieved 96%. The free
radical copolymerization of conjugated soybean oil with acrylonitrile (AN) and dicyclopentadiene (DCP) was studied. AIBN was
used as the initiator. FT-IR and 1H-NMR results indicates that the conjugated soybean oil with AN and DCP did occur free radical copolymerization with the initiator
AIBN. The product is light yellow powder. The thermal properties of the soy-based copolymer were investigated by TG and DSC.
The initial degradation temperature of polymers is higher then 250 °C. 相似文献
959.
Phosphorus flows and use efficiencies in production and consumption of wheat, rice, and maize in China 总被引:5,自引:0,他引:5
Increasing fertilizer phosphorus (P) application in agriculture has greatly contributed to the increase of crop yields during the last decades in China but it has also increased P flows in food production and consumption. The relationship between P use efficiency and P flow is not well quantified at national level. In present paper we report on P flows and P use efficiencies in rice, wheat, and maize production in China using the NUFER model. Conservation strategies for P utilization and the impact of these strategies on P use efficiency have been evaluated. Total amounts of P input to wheat, rice, and maize fields were 1095, 1240, and 1128 Gg, respectively, in China, approximately 80% of which was in chemical fertilizers. The accumulation of P annually in the fields of wheat, rice, and maize was 29.4, 13.6, and 21.3 kg ha−1, respectively. Phosphorus recovered in the food products of wheat, rice, and maize accounted for only 12.5%, 13.5%, and 3.8% of the total P input, or 3.2%, 2.6%, and 0.9% of the applied fertilizer P, respectively. The present study shows that optimizing phosphorus flows and decreasing phosphorus losses in crop production and utilization through improved nutrient management must be considered as an important issue in the development of agriculture in China. 相似文献
960.
Wang Q Wang L Chen X Rao KM Lu SY Ma ST Jiang P Zheng D Xu SQ Zheng HY Wang JS Yu ZQ Zhang R Tao Y Yuan J 《Environmental science and pollution research international》2011,18(6):987-996