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1.
HPLC法测定废水中苯胺类化合物   总被引:3,自引:0,他引:3  
用乙醚为提取有机相,提取前先经碱化,提取后加酸使苯胺成盐,吹去乙醚,用HPLC法测定苯胺类化合物。方法适用于测定废水中苯胺类化合物。检出限:苯胺3.0ng,邻硝基苯胺0.5ng,对硝基苯胺1.0ng。线性范围:苯胺0.817-13.072μg/ml,邻硝基苯胺0.1464-2.3424μg/ml,对硝基苯胺0.253-4.048μg/ml。精密度(CV):苯胺2.38%,邻硝基苯胺1.09%,对硝  相似文献   

2.
建立溴甲酚绿(BCG)-溴化十六烷基吡啶(CPB)光度法测定水中阴离子表面活性剂的方法。实验表明,最适合的pH范围为5.5-9.0,λmax=614nm,在86μgCPB存在下,十二烷基苯磺酸钠(SDBS)和十二烷基硫酸钠(SDS)分别在0-80μg/10ml和0-75μg/10ml范围内符合比耳定律,其表观摩尔吸光系数分别为2.9×104和3.1×104L·mol-1·cm-1。用此法测定了河水和生活废水中的阴离子表面活性剂,相对标准偏差<3.0%,样品加标平均回收率为99.3%。  相似文献   

3.
热处理对含氮活性碳纤维脱除SO2能力的影响   总被引:3,自引:0,他引:3  
考察中高温热处理对含氮沥青活性碳纤维「PACF(NH3)」脱除SO2的能力的影响结果表明,在900-1100℃尤其是在1000℃下热处理可显著提高PACF(NH3)脱除SO2的能力,当在30℃下模拟烟气中SO2、O2和H2O的浓度分别为0.002ml/ml,0.1ml/ml和0.1ml/ml,气休流动速率为100ml/min时,0.25g的3种不同比表面物PACF(NH3)完全除去OS2的时间分别  相似文献   

4.
考察中高温热处理对含氮沥青基活性碳纤维[PACF(NH3)]脱除SO2的能力的影响结果表明,在900—1100℃尤其是在1000℃下热处理可显著提高PACF(NH3)脱除SO2的能力.当在30℃下模拟烟气中SO2、O2和H2O的浓度分别为0.002ml/ml、0.1ml/ml和0.1ml/ml,气体流动速率为100ml/min时,0.25g的3种不同比表面积的PACF(NH3)完全除去SO2的时间分别从热处理前的0.25h、1h和1h延长到热处理后的1h、2h和3.5h,SO2穿透后的稳态浓度从热处理前的73%、54%和38%下降到热处理后的32%、24%和10%.脱硫活性的提高主要是由于热处理增强了PACF(NH3)对SO2和O2的吸附作用,加速了SO2的氧化反应.  相似文献   

5.
金属氧化物对CO还原NO反应的催化作用   总被引:9,自引:1,他引:8  
采用固定床流动反应器,研究CuO、Cr2O3、MnO2、Fe2O3、Ni2O3等单元金属氧化物及它们形成的复合氧化物对CO还原NO反应的催化活性。结果表明,在500℃800ml/m^3NO-0.2%CO-2.0%CO2-N2气氛中CO还原NO的能力很小,稳定还原率仅为1.50%。  相似文献   

6.
反相高效液相色谱法测定土壤中微量灭多威   总被引:2,自引:0,他引:2  
研究了土壤中灭多威的最佳提取分离方法和HPLC的测定方法,测定土壤灭多威的检测限为0.1ng,线性范围1.0-20μg/ml,高、中、低3种浓度的平均加标回收率96.1%-100.2%,变异系数小于5%。本法操作简便,准确度高,精密良好,其它杂质基本不干扰。  相似文献   

7.
研制出一种新的阴离子表面活性电极,电极膜最佳组成:THDA-DBS5mg,DBP04ml,NB0.3ml,PVC粉0.2g,电极线性范围1×10^-3-8.1×10^-7mol/L,级差58mV/dec,对DBS和SDS检测分别为5.6×10^-7mol/L和7.4×10^-7mol/L。  相似文献   

8.
上流式厌氧污泥床(UASB)处理制药废水的研究   总被引:12,自引:1,他引:11  
用上流式厌氧污泥床(UASB)在自然温度条件下处理VC、SD和葡萄糖生产废水。反应器容积100L,发酵温度-24℃,进水CODcr3000-5000ml/L,有机负荷3-6kgCOD/(m^3.d),HRT为18-24h,产气率达到0.3m^3/kgCOD,甲烷含量70%,CODcr去除率达到90%,取得较好的实验效果,为厌氧处理较低深度的制药废水找出可行的途径。  相似文献   

9.
介绍了用高流量大气采样器和瓦特曼滤膜采集样品,以硝酸-高氯酸消化,无火焰原子吸收分光光度法测定海洋气溶胶中铜、铅、镉。对高流量大气采样流量校准、滤膜选用,仪器测试条件及消化方法进行试验和讨论。本方法检测限分别为铜1.8ng/m3、铅1.4ng/m3、镉0.7ng/m3,变异系数分别为铜9.6%、铅8.9%、镉18.0%。  相似文献   

10.
介绍了碳纤维束汞膜微电极的制作过程,研究此电极的伏安特性,用阳极溶出伏安法测定汽车尾气中的铅含量,确定适宜的实验条件,该法简便,快速,灵敏度高,重现性好,检出限为0.1ng.ml^-1,线性范围1.0-20ng/ml^-1,相对标准偏差9.4%。  相似文献   

11.
Soil contaminated with heavy metals cadmium(Cd)and lead(Pb)is hard to be remediated.Phytoremediation may be a feasible method to remove toxic metals from soil,but there are few suitable plants which can hyperaccumulate metals.In this study,Cd and Pb accumulation by four plants including sunflower(Helianthus annuus L.),mustard(Brassica juncea L.),alfalfa(Medicago sativa L.), ricinus(Ricinus communis L.)in hydroponic cultures was compared.Results showed that these plants could phytocxtract heavy metals, the ability of accumulation differed with species,concentrations and categories of heavy metals.Values of BCF(bioconcentration factor)and TF(translocation factor)indicated that four species had dissimilar abilities of phytoextraction and transportation of heavy metals.Changes on the biomass of plants,pH and Eh at different treatments revealed that these four plants had distinct responses to Cd and Pb in cultures.Measurements should be taken to improve the phytoremediation of sites contaminated with heavy metals,such as pH and Eh regulations,and so forth.  相似文献   

12.
The oxidation of As(Ⅲ) with potassium permanganate was studied under conditions including pH, initial As(Ⅲ) concentration and dosage of Mn(Ⅶ). The results have shown that potassium permanganate was an effective agent for oxidizing of As(Ⅲ) in a wide pH range. The pH value of tested water was not a significant factor affecting the oxidation of As(Ⅲ) by Mn(Ⅶ). Although theoretical redox analyses suggest that Mn(Ⅶ) should have better performance in oxidization of As(Ⅲ) within lower pH ranges, the experimental results show that the oxidation efficiencies of As(Ⅲ) under basic and acidic conditions were similar, which may be due to the adsorption of As(Ⅲ) on the Mn(OH)2 and MnO2 resulting from the oxidation of As(Ⅲ).  相似文献   

13.
Laogang landfill near Shanghai is the largest landfill in China, and receives about 10000 t of daily garbage per day, Samples of topsoil and plants were analyzed to evaluate mercury pollution from the landfill. For topsoil samples, there were significant correlations among total mercury (HgT), combinative mercury (Hgc) and gaseous mercury (HgG), and content of total organic carbon (TOC), but, no significantly relationship was found between Hg content and filling time. Hg content changes in vertical profiles with time showed that the average Hgv of profiles 1992, 1996, and 2000 was similar, but their average HgG was quite different. HgT was significantly correlated with Hgc in profile 1992 and 2000, and Hgv was significantly correlated with Hg6 in profile 1996. HgG/Hgv ratio in profile samples decreased in the order of (HgG,/HgT)1992〉(HgG/HgT)1996〉〉(HgG/HgT)2000. A simple outline of Hg release in landfill could be drawn: with increasing of filling time, degradation undergoes different biodegradation, accordingly, gaseous mercury goes through small, more, and small proportion to total mercury. Distribution of Hg in plants was inhomogeneous, following the order of leaf〉root〉stem. The highest value of leaf may be associated with higher atmospheric Hg from landfill. Ligneous plants (e.g. Phyllostachys glanca, Prunus salicina and Ligustrum lucidum) are capable of enriching more Hg than herbaceous plants.  相似文献   

14.
Phytoremediation is a potential cleanup technology for the removal of heavy metals from contaminated soils.Bidens maximowicziana is a new Pb hyperaccumulator,which not only has remarkable tolerance to Pb but also extraordinary accumulation capacity for Pb.The maximum Pb concentration was 1509.3 mg/kg in roots and 2164.7 mg/kg in overground tissues.The Pb distribution order in the B. maximowicziana was:leaf>stem>root.The effect of amendments on phytoremediation was also studied.The mobility of soil Pb and the Pb concentrations in plants were both increased by EDTA application.Compared with CK(control check),EDTA application promoted translocation of Pb to overground parts of the plant.The Pb concentrations in overground parts of plants was increased from 24.23-680.56 mg/kg to 29.07-1905.57 mg/kg.This research demonstrated that B.maximowicziana appeared to be suitable for phytoremediation of Pb contaminated soil,especially,combination with EDTA.  相似文献   

15.
Decomposition of alachlor by ozonation and its mechanism   总被引:1,自引:0,他引:1  
Decomposition and corresponding mechanism of alachlor, an endocrine disruptor in water by ozonation were investigated. Results showed that alachlor could not be completely mineralized by ozone alone. Many intermediates and final products were formed during the process, including aromatic compounds, aliphatic carboxylic acids, and inorganic ions. In evoluting these products, some of them with weak polarity were qualitatively identified by GC-MS. The information of inorganic ions suggested that the dechlorination was the first and the fastest step in the ozonation of alachlor.  相似文献   

16.
The influence of the nonionic surfactant Tween 80 on pentachlorophenol (PCP) oxidation catalyzed by horseradish peroxidase was studied. The surfactant was tested at concentrations below and above its critical micelle concentration (CMC). Enhancement of PCP removal was observed at sub-CMCs. The presence of Tween 80 in the reaction mixture reduced enzyme inactivation which occurred through a combination of free radical attack and sorption by precipitated products. A simple first-order model was able to simulate time profiles for enzyme inactivation in the presence or absence of Tween 80. At supra-CMCs, the surfactant caused noticeable reductions in PCP removal, presumably through micelle partitioning of PCP which precluded the hydrophobic PCP molecule from interacting with the enzyme.  相似文献   

17.
The Xijiang River is the major source of water for about 4.5 millions of urban population and 28.7 millions of rural population. The water quality is very important for the health of the rural population. The concentration and distribution of chlorobenzenes (CBs) in both water and waterweeds collected from 4 stations in the Xijiang River (Gangdong section) of the Pearl River in April and November were determined. The result showed that nearly every congener of CBs was detected. The total contents of CBs (∑CBs) in the river water ranged from 111.1 to 360.0 ng/L in April and from 151.9 to 481.7 ng/L in November, respectively. The pollution level of CBs in the water in April was higher than that in November. The contents of ∑ CBs in waterweeds ranged from 13.53×102 μg/g to 38.27×102μg/g dry weight (dw). There was no significant difference between April and November in waterweeds. The distribution of CBs in roots, caulis, and leaves of Vallisneria spiralis L. showed different patterns. The leaves mainly contained low-molecular-weight CBs(DCBs), whereas the roots accumulated more PCBs and HCBs. The average lgBCFlip (bioconcentration factor) of CBs ranged from 0.64 to 3.57 in the waterweeds. The spatial distribution character of CBs in the Xijiang River was: Fengkai County < Yunan County <Yun'an County < Gaoyao County according to the ∑CBs, and the pollution deteriorated from the upstream to the downstream of the Xijiang River. Further analysis demonstrated that the discharge of waste containing CBs may be the main source of CBs pollution in the Xijiang River.  相似文献   

18.
Degradation of 2,4-dichlorophenol(2,4-DCP)was studied in a novel three-electrode photoelectrocatalytic(PEC)integrative oxidation process,and the factors influencing the degradation rate,such as applied current,flow speed of O_2,pH,adscititious voltage and initial 2,4-DCP concentration were investigated and optimized.H_2O_2 was produced nearby cathode and Fe~(2 )continuously generated from Fe anode in solution when current and O_2 were applied,so,main reactions,H_2O_2-assisted TiO_2 PEC oxidation and E-Fenton reaction,occurred during degradation of 2,4-DCP in this integrative system.The degradation ratio of 2,4-DCP was 93% in this integrative oxidation process,while it was only 31% in E-Fenton process and 46% in H_2O_2-assisted TiO_2 PEC process.So,it revealed that the degradation of 2,4-DCP was improved greatly by photoelectrical cooperation effect.By the investigation of pH,it showed that this integrative process could work well in a wide pH range from pH 3 to pH 9.  相似文献   

19.
The influence of coexisting copper (Cu) ion on the degradation of pesticides pyrethroid cypermethrin and cyhalothrin in soil and photodegradation in water system were studied.Serial concentrations of the pesticides with the addition of copper ion were spiked in the soil and incubated for a regular period of time,the analysis of the extracts from the soil was carried out using gas chromatography (GC).The photodegradation of pyrethroids in water system was conducted under UV irradiation.The effect of Cu~(2 ) on the pesticides degradation was measured with half life (t_(0.5)) of degradation.It was found that a negative correlation between the degradation of the pyrethroid pesticides in soil and Cu addition was observed.But Cu~(2 ) could accelerate photodegradation of the pyrethroids in water.The t_(0.5) for cyhalothrin extended from 6.7 to 6.8 d while for cypermethrin extended from 8.1 to 10.9 d with the presence of copper ion in soil.As for photodegradation,t_(0.5) for cyhalothrin reduced from 173.3 to 115.5 rain and for cypermethrin from 115.5 to 99.0 min.The results suggested that copper influenced the degradation of the pesticides in soil by affecting the activity of microorganisms.However, it had catalyst tendency for photodegradation in water system.The difference for the degradation efficiency of pyrethroid isomers in soil was also observed.Copper could obviously accelerate the degradation of some special isomers.  相似文献   

20.
以三峡大学的校园河道求索溪为研究对象,利用综合水质标识指数法确定求索溪水质类别,分析其水质时空变化规律,并利用对应分析法得出求索溪中不同监测点的主要污染因子.研究结果表明:求索溪整体的综合水质标识指数为7.423,整体水质为劣V类(地表水环境质量标准GB 3838-2002)且黑臭.从时间变化来看,求索溪4月份的水质最差,5月份次之,4、5月份所有监测点的水质都劣于V类且黑臭;8月份水质最好,水质为Ⅳ类;从空间分布来看,8个监测点综合水质标识指数均超过6.0,水质为劣V类,其中6号监测点的水质相对最好,监测点3号的水质相对最差;对应分析法得出求索溪的整体水体污染程度受总氮因子的影响最大,其次为总磷.该研究拟为求索溪及类似校园河道的水环境治理研究提供基础依据和参考.  相似文献   

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