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991.
Fenton试剂氧化处理油墨废水的条件优化 总被引:1,自引:0,他引:1
采用Fenton试剂氧化对油墨废水进行处理,研究了FeSO4浓度、H2O2浓度、初始pH和反应时间及废水初始COD浓度等因素对废水剩余COD的影响.结果表明,Fenton试剂氧化的最佳条件为FeSO4浓度800 mg/L、初始pH 2.5、H2O2浓度800 mg/L、处理时间180 min.此条件下,当油墨废水在初始COD小于876 mg/L时,经Fenton氧化处理后油墨废水的剩余COD在98 mg/L以下,出水能够满足排放标准. 相似文献
992.
[目的]研究Fenton氧化降解活性艳红X-3B的条件及历程。[方法]利用Fenton氧化工艺,分析3种不同初始浓度的活性艳红X-3B废水的降解条件,同时利用GC-MS对其降解产物及历程进行研究。[结果]当H2O2∶Fe2+(摩尔比)=3.1时,COD去除效果最好,随着Fe2+投加量的增加,废水会变成铁红色,同时沉淀物增加;对于COD分别为200、400和800 mg/L的废水,H2O2投加量分别为0.5、1.0、3.5 ml,废水的初始pH为4~5时,COD的去除率最高。Fenton氧化反应的速度非常快,大部分的降解都发生在初始的5 min之内。[结论]Fenton氧化技术是一种高效降解难降解染料的实用技术。 相似文献
993.
内源性动力和外生性动力构成了农业信息服务的动力系统,内源性动力是农业信息服务的基础,外生性动力是农业信息服务的推动力量。目前,农业信息服务的内源性动力需求强烈,外生性动力供给不足,必须建立供给与需求相适应的动力系统,才能保证农业信息服务的可持续发展。 相似文献
994.
[目的]研究水葫芦(Eichhornia crassipes)根系活力与水体中氮浓度的关系。[方法]以不同氮营养水平培养水葫芦,研究水体中氮浓度对水葫芦根系活力的影响。[结果]氮浓度对水葫芦根系有较大的影响,在适宜的氮浓度水环境中水葫芦生长良好,并且根系活力和根系过氧化物酶活性都比较高。其中3.5 mg/L氮水平处理的水葫芦根系活力和根系过氧化物酶活性达到最高,过高的氮水平不但抑制水葫芦的根系活力,同时也抑制水葫芦根系的过氧化物酶活性。[结论]不同氮营养水平不仅影响水葫芦的根系活力,而且对根系过氧化物酶的活性也有明显影响。 相似文献
995.
Bacterial autolysate, a down stream product of bacterial biomass grown on natural gas by mainly the methanotrophic bacteria Methylococcus capsulatus, was fed at 8% as is to broiler chickens from 1 to 35 days of age for studies of fatty acid composition, lipid oxidation and sensory quality of thigh meat stored frozen for 6 month at -18 °C or -80 °C. Lipid oxidation was measured by thiobarbituric acid reactive substances (TBARS) and volatile profile by dynamic headspace gas chromatography. Adding bacterial autolysate to diets did not affect the total content of saturated, monounsaturated or polyunsaturated fatty acids in thigh meat, but increased the levels of C14:0, C16:0, C18:0 and C16:1n-7 and reduced the levels of C18:1n-7, C18:2n-6 and C18:3n-3 fatty acids. Feeding of bacterial autolysate tended (p < 0.08) to reduce TBARS of meat samples. Contents of volatiles were generally low, but feeding of bacterial autolysate significantly reduced levels of butanal (p < 0.04) and tended to reduce levels of hexanal (p < 0.11), pentanal (p < 0.09), 1-penten-3-ol (p < 0.08) and butanone (p < 0.08). Bacterial autolysate had no effects on sensory quality parameters of meat related to odour and flavour. To conclude, adding bacterial autolysate to diets did not affect the relative proportion of saturated, monounsaturated or polyunsaturated fatty acids, but reduced content of volatiles in frozen-stored broiler meat. The reduced susceptibility to lipid oxidation in broiler meat may be related to antioxidant properties of the bacterial autolysate. 相似文献
996.
997.
The phytochemical profiles of Morus australis roots, stems and twigs were firstly compared by HPLC analysis. It was found that Morus australis stem extract mainly contained one known tyrosinase inhibitor, oxyresveratrol, while its root and twig extract might contain some unknown potential tyrosinase inhibitors. The root extract of Morus australis was further investigated in this study. One new compound, austraone A, together with 21 known compounds, was isolated and their structures were identified by interpretation of MS and NMR data. In the tyrosinase inhibitory testing, some of them, such as oxyresveratrol, moracenin D, sanggenon T, and kuwanon O, exhibited stronger tyrosinase inhibitory activities than that of kojic acid. These results suggested the Morus australis root extract as a good source of natural tyrosinase inhibitors with a great potential to be used in foods as anti-browning agents and in cosmetics as skin-whitening agents. 相似文献
998.
朝阳市林业可持续发展对策 总被引:4,自引:0,他引:4
"十年九旱"是朝阳市最基本的市情。林业作为一个具有产业属性的社会公益事业以及生态系统的主体和基础,对改变朝阳恶劣气候现状、捍卫生态安全、提升"生态软实力"具有重要意义。该文就朝阳林业可持续发展问题提出有针对性的具体对策,认为化解朝阳林业发展困局必须从解决"系统问题"和"技术问题"两方面着手方能奏效,必须走科技兴林的路子,同时考虑到人的因素和政策层面的问题。 相似文献
999.
Tnia C. Leite Fernanda Picoli Diogo de A. Lopes Matheus D. Baldissera Carine F. Souza Bernardo Baldisserotto Ana Paula O. Costa Luisa Nora Alexandre H. Marcelino Aleksandro S. Da Silva 《Aquaculture Research》2021,52(1):395-402
The aim of the present study was to determine whether açai oil (Euterpe oleraceae) addition in the diets of juvenile Nile tilapia (Oreochromis niloticus) in biofloc system would stimulate hepatic energy metabolism and antioxidant responses. Treatments are as follows: T0 (6%‐soybean oil), T1 (1%‐AÇAI; 5%‐SOY), T3 (3% AÇAI; 3%‐SOY) and T6 (6%‐AÇAI). In the liver, reactive oxygen species levels were significantly lower in T1, T3 and T6 than in T0, lipid peroxidation levels were significantly lower in T3 and T6, and nitric oxide levels were significantly lower in the T6 than in T0. Glutathione peroxidase activity was significantly higher in the T3 and T6 than in T0, while superoxide dismutase activity and total antioxidant capacity levels were significantly higher in the T6 than in T0. Adenylate kinase activity was significantly lower in the T6 than in T0. These results suggest that the açai oil addition in Nile tilapia diets stimulated antioxidant responses. 相似文献
1000.
介绍了液力缓速器的结构和工作原理,以某款商用车匹配采埃孚液力缓速器为例,详细阐述了商用车匹配缓速器时的空间布置、控制策略、冷却回路等设计内容.通过实车转鼓试验研究缓速器的制动性能.结果表明:整车匹配液力缓速器时,适当增大整车散热功率,能保证液力缓速器稳定的持续制动性能. 相似文献