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651.
主要研究了DL1210型纳滤膜去除水中邻苯二甲酸二丁酯(DBP)、邻苯二甲酸二(2-乙基己基)酯(DEHP)、乐果和莠去津的影响因素,考察了温度、pH值、初始浓度、跨膜压力(TMP)和运行时间对膜通量和截留率的影响。结果表明,纳滤工艺是去除水中微量DBP、DEHP、乐果和莠去津的有效方法,初始pH值和温度的升高会导致纳滤膜对DBP、DEHP、乐果和莠去津的截留率的降低,膜对DBP和DEHP的截留率随初始浓度的升高而降低,TMP和运行时间不会对膜通量和目标污染物的截留率造成显著影响。当初始pH为5、初始浓度为5μg/L、温度为5℃、TMP为0.4 MPa时,纳滤工艺对DBP、DEHP、乐果和莠去津的截留率达到最佳,分别为91.8%、89.8%、98.02%和77.6%,出水中DBP、DEHP、乐果和莠去津浓度分别为0.41、0.49、0.099和1.12μg/L。 相似文献
652.
Pollution characteristics of 23 veterinary antibiotics in livestock manure and manure-amended soils in Jiangsu province,China 总被引:3,自引:0,他引:3
Xin Y. Guo Li J. Hao Pan Z. Qiu Rong Chen Jing Xu Xiang J. Kong 《Journal of environmental science and health. Part. B》2016,51(6):383-392
The aim of this study was to investigate the pollution characteristics of typical veterinary antibiotics in manure and soil of livestock farms in Jiangsu province. This investigation employed solid-phase extraction (SPE) coupled with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). A total of 53 manure and 50 amended soil samples from 16 livestock farms in Jiangsu province were collected for analysis. In the manure samples, the highest detected frequencies and concentrations were those of tetracyclines (TCs, 54.1 ± 5775.6 μgkg?1), followed by fluoroquinolones (FQs, 8.4 ± 435.6 μgkg?1), sulphonamides (SAs, 3.2 ± 5.2 μgkg?1) and macrolides (MACs, 0.4 ± 110.5 μgkg?1). Statistical analysis was used to illuminate the pollution characteristics of 23 veterinary antibiotics for various animal types and different regions in Jiangsu province. The results showed that the pollution level in cow manure was relatively lower compared with pig and chicken manure due to the relative restriction of medication. Furthermore, contamination was serious in amended soil from chicken farms. The pollution level in manure among different regions was higher to the south and north compared with the centre of the region. The same outcome was found for soil. Antibiotic residues in organic fertilizer were also investigated in this study. We found that although the detected concentration was lower in organic fertilizer than in fresh manure, detection frequencies (10–90%) were high, especially for roxithromycin (90%) in MACs (30–90%). This finding suggests attention should be paid to the pollution levels in organic fertilizer. This study is the first extensive investigation of the occurrence and distribution of many kinds of typical veterinary antibiotics in manure and soil from livestock farms of Jiangsu province. This investigation systematically assesses veterinary antibiotics usage and related emissions in southeast China. 相似文献
653.
污水快速渗滤土地处理研究进展 总被引:3,自引:0,他引:3
针对RI系统的污染物去除机制、运行方式、系统恢复以及实践应用等方面的研究进展作一综述。RI技术的应用有着广阔的前景 ,必将促进我国环境保护与生态建设的发展 相似文献
654.
Wang H He M Lin C Quan X Guo W Yang Z 《Environmental monitoring and assessment》2007,133(1-3):231-242
Surface sediment samples from 12 sites of the three selected rivers in Daliaohe River watershed (Hunhe River, Taizihe River
and Daliaohe River) were analyzed with the objective of establishing sources and hazard of the organochlorinae pesticides
(OCPs) and polychlorinated biphenyl (PCBs) in surface sediments. The total concentrations of OCPs varied from 3.06 to 23.24
ng g−1. ∑HCH (α-HCH, β-HCH, δ-HCH, γ-HCH), ∑DDT (p, p′-DDE, p, p′-DDD, o, p′-DDT, p, p′-DDT) and ∑Cyclodiene (Heptachlor, Aldrin,
Heptachlor epoxide, Dieldrin, Endrin) ranged from 1.86 to 21.48, 0.5 to 2.81 and 0.56 to 1.53 ng g−1, respectively. Results of OCPs also illustrate that the most dominant pollutants among the OCPs was ∑HCH, and γ-HCH was the
most dominant isomer in HCH, which was evidence of recent input of lindane. It possibly came from the runoff of polluted soils
and long-scale transportation. Total PCB concentrations ranged between 1.88 and 16.88 ng g−1. The peak concentrations of PCBs were found in sediments from station T5 and D3, which are in the vicinity of industrial
areas and ferry, respectively. These data show a moderate level of OCPs and PCBs contaminations compared to that in other
countries. 相似文献
655.
Bohan Liao Zhaohui Guo Qingru Zeng Anne Probst Jean-Luc Probst 《Water, Air, & Soil Pollution: Focus》2007,7(1-3):151-161
Leaching experiments of rebuilt soil columns with two simulated acid rain solutions (pH 4.6–3.8) were conducted for two natural
soils and two artificial contaminated soils from Hunan, south-central China, to study effects of acid rain on competitive
releases of soil Cd, Cu, and Zn. Distilled water was used in comparison. The results showed that the total releases were Zn>Cu>Cd
for the natural soils and Cd>Zn≫Cu for the contaminated soils, which reflected sensitivity of these metals to acid rain. Leached
with different acid rain, about 26–76% of external Cd and 11–68% external Zn were released, but more than 99% of external
Cu was adsorbed by the soils, and therefore Cu had a different sorption and desorption pattern from Cd and Zn. Metal releases
were obviously correlated with releases of TOC in the leachates, which could be described as an exponential equation. Compared
with the natural soils, acid rain not only led to changes in total metal contents, but also in metal fraction distributions
in the contaminated soils. More acidified soils had a lower sorption capacity to metals, mostly related to soil properties
such as pH, organic matter, soil particles, adsorbed SO4
2−, exchangeable Al3+ and H+, and contents of Fe2O3 and Al2O3. 相似文献
656.
657.
以丙烯酰胺(AM)和烷基酚聚醚(APAP)为单体,采用反相乳液聚合法制备了流动性好的非离子型聚丙烯酰胺絮凝剂(PAM-APAP)。考察了乳化剂和引发剂的种类、单体总质量分数、单体配比和反应温度等因素对聚合反应的影响。实验结果表明,制备PAM-APAP的最佳工艺条件为:单体总质量分数35%、m(AM)∶m(APAP)=9.0∶1.0、Span80+Tween80复配乳化剂加入量为油水总质量的7%、m(Span80)∶m(Tween80)=7.0∶1.5、V50加入量为单体总质量的1.5‰、反应温度50℃。PAM-APAP具有较好的絮凝效果,与其他絮凝剂相比用量较少,在加入量为100mg/L时,对聚合物驱油中产生的含聚合物污水的浊度去除率为87.9%,去油率为89.5%,且絮体不黏壁。 相似文献
658.
随着经济的高速发展,环境污染事故也呈现出上升的势头,环境污染事故不仅造成了环境危害,而且对人民群众的安全产生了重大威胁。鉴于环境污染事故的多发性、危害性,应急处置显然非常重要,而构建强大的应急处置信息系统有助于应急处置和分析决策的顺利进行。本文分析了环境应急处置需求,提出了建立环境污染应急管理信息系统的设计框架。 相似文献
659.
从山海关区农村生态环境现状出发,客观分析了农村生态环境存在的水体污染、土壤污染、水土流失等问题,以及影响农村生态环境的主要因素,如污水和垃圾的无组织排放、化肥和农药的不合理使用、基础设施差、监管缺位等,提出应从环保体制、环保意识、基础设施建设、自然资源保护、污染防治、强化监管等方面采取切实可行的措施,保护农村生态环境。 相似文献
660.
灰色系统方法在城市生活垃圾量预测中的应用 总被引:2,自引:0,他引:2
利用灰色关联分析方法分析了影响城市生活垃圾量的因素,建立了生活垃圾量的GM(1,1)预测模型,预测了未来的城市生活垃圾量。该法具有较高的精度,简便,可行。 相似文献