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超声波技术对水中有机污染物的降解 总被引:17,自引:0,他引:17
本文介绍了超声波降解水中有机污染物的原理及影响降解效果的因素,超声波降解是基于超声空化,影响因素主要有声强、有机污染物性质、温度、pH值等。 相似文献
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超声波与其他技术联用降解有机物的研究进展 总被引:1,自引:0,他引:1
介绍了国内外超声波与其他技术联用在降解水中有机污染物方面的研究进展。多项研究表明,超声波与Fenton型试剂、紫外光、铁、生物催化剂、电解、臭氧等手段联用可大大提高有机物降解率,应用前景广阔。 相似文献
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超声技术在废水处理中的应用 总被引:1,自引:0,他引:1
利用超声波降解水体中的化学污染物的工艺方法,具有操作简单方便,降解速度快,不产生二次污染等特点,可单独或与其它水处理技术联合使用,是一种极具发展潜力的废水处理技术,尤其在含有毒性高、难降解有机污染物的废水处理领域具有良好的应用前景。 相似文献
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超声波处理有机废水技术及应用 总被引:1,自引:0,他引:1
超声波处理污水技术是一项很有发展前途的水处理技术,它集高级氧化、焚烧、超临界氧化于一体,操作简单方便,无二次污染。文中对超声波处理有机废水原理和影响超声波场中有机物污染物的降解因素做了综述,并介绍了在处理印染和制革废水方面的应用。 相似文献
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超声波对甲基橙的降解性能研究 总被引:1,自引:0,他引:1
超声是一种处理有机污染物废水的新型技术,近10年来,超声降解水体中有机污染物的研究十分活跃,但由于此技术存在着费用商、降解效率低等一些局限性,而更有效的方法是将超声技术与其他水处理技术联合使用。该研究是选用甲基橙作为降解对象,以自制的纳米TiO2为催化剂,采用超声波氧化法,研究了超声时阅、pH、初始浓度、不同浓度、催化剂种类,联合H2O2、TiO2等因素对甲基橙超声波降解率的影响可行性研究。结果表明,超声时间延长,降解率增加,超声100min后降解率达13.6%,溶液初始浓度由4mg/L增加到10mg/L,降解率由6.3%上升到13.6%,在酸性条件下有利于甲基橙的降解,加入H2O2(30%的量为3mL即可嚷显提高甲基橙的降解率。超声波一光催佬氧化处理含甲基橙废水时,能使降解效率大大提高,而益要大于两者之间的简单相加,说明超声波和光催化之间存在协同作用。 相似文献
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This study shows how aerosol organic oxygen data could provide new information about organic aerosol mass, aqueous solubility of organic aerosols, formation of secondary organic aerosol (SOA) and the relative contributions of anthropogenic and biogenic sources. For more than two decades, atmospheric aerosol organic mass (OM) concentration has been estimated by multiplying the measured carbon content by an assumed (OM)-to-organic carbon (OC) factor, usually 1.4. However, this factor can vary from 1.0 to 2.5 depending on location. This large uncertainty about aerosol organic mass limits our understanding of the influence of organic aerosol on climate, visibility and health. New examination of organic aerosol speciation data shows that the oxygen content is responsible for the observed range in the OM-to-OC factor. When organic oxygen content is excluded, the ratio of non-oxygen organic mass to carbon mass varies very little across different environments (1.12 to 1.14). The non-oxygen-OM-to-OC factor for all studied sites (urban and non-urban) averaged 1.13. The uncertainty becomes an order of magnitude smaller than the uncertainty in the best current estimates of organic mass to organic carbon ratios (1.6 ± 0.2 for urban and 2.1 ± 0.2 for non-urban areas). This analysis suggests that, when aerosol organic oxygen data become available, organic aerosol mass can be quite accurately estimated using just OC and organic oxygen (OO) without the need to know whether the aerosol is fresh or aged. In addition, aerosol organic oxygen data will aid prediction of water solubility since compounds with OO-to-OC higher than 0.4 have water solubilities higher than 1 g per 100 g water. 相似文献
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A comparative study of farm nutrient budgets and nutrient flows of certified organic and non-organic farms in China,Brazil and Egypt 总被引:3,自引:0,他引:3
Myles Oelofse Henning Høgh-Jensen Lucimar S. Abreu Gustavo F. Almeida Ahmed El-Araby Qiao Yu Hui Andreas de Neergaard 《Nutrient Cycling in Agroecosystems》2010,87(3):455-470
Increased demand for certified organic products has led to an increase in the number of certified organic farms in developing
countries. Knowledge of farmer nutrient management practices on certified organic farms in developing countries is limited.
Thus, the aim of this study was to investigate the impact of the adoption of certified organic agriculture on farm nutrient
flows and nutrient budgets, and evaluate to which degree organic farms comply with organic principles relating to nutrient
management. The study is based on five case studies of different types of certified organic farming systems in Brazil, Egypt
and China. Farm nutrient flows and nutrient budgets for nitrogen, phosphorous and potassium were created for each farm. Four
of the five organic systems studied had nutrient surpluses on the farm budget. The surpluses were of varying magnitude. The
main difference between organic and non-organic farm nutrient flows was the replacement of mineral fertilizers with organic
inputs. However, the magnitude of nutrient flows were generally similar for organic and non-organic farms. Certified organic
farms with positive nutrient budgets had a heavy reliance on external inputs. Continued high dependence on an external supply
of nutrients, which typically originate from mineral sources, poses a significant challenge to organic farmers’ fulfilment
of the principles of organic agriculture. 相似文献
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有机化学的前沿和教学中的思考 总被引:2,自引:1,他引:1
本文对有机化学的一些前沿研究做了介绍,包括生命有机科学的糖化学、DNA重组技术和定点突变技术、蛋白质化学的分子识别技术、绿色化学、有机材料科学的纳米有机材料、富勒烯家族、有机光电功能材料等各领域,并对高校有机化学教学和现代有机化学前沿如何结合做了探讨。 相似文献
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总结了有机过氧化物、有机过氧化物与不相容物混合、有机过氧化物与稀释剂混合等条件下的热动力学及热危险参数确定方法,探讨了有机过氧化物与其他物质相容性判据以及稀释剂减敏效果判据,论述了有机过氧化物自加速分解温度的确定方法,分析了采用定量结构性能相关方法 (quantitative structureproperty relationship,QSPR)预测有机过氧化物热危险性的可行性,为有机过氧化物热分解机理研究以及安全生产、储运和使用提供了参考。 相似文献
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挥发性有机物(Volatile Organic Compounds,VOCs)是强挥发性有机化学物质的总称,挥发性有机物在常温下,是一种逸散性排放的物质,对空气和环境的污染比较严重,对人体的健康也会产生极大的威胁。挥发性有机物主要来源石油化工产品、汽车尾气、化学溶剂、涂料油漆、废物处理等等,因此对挥发性有机物的污染受到越来越多的人重视。通过利用气相色谱对空气和室内进行测量、分析、研究。 相似文献