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1.
This work described the development, optimization and validation of an analytical method for rapid detection of multiple-class pharmaceuticals in both municipal wastewater and sludge samples based on ultrasonic solvent extraction, solid-phase extraction, and ultra high performance liquid chromatography-tandem mass spectrometry quantification. The results indicated that the developed method could effectively extract all the target pharmaceuticals (25) in a single process and analyze them within 24 min. The recoveries of the target pharmaceuticals were in the range of 69%-131% for wastewater and 54%-130% for sludge at different spiked concentration levels. The method quantification limits in wastewater and sludge ranged from 0.02 to 0.73 ng/L and from 0.02 to 1.00μg/kg, respectively. Subsequently, this method was validated and applied for residual pharma- ceutical analysis in a wastewater treatment plant located in Beijing, China. All the target pharmaceuticals were detected in the influent samples with concentrations varying from 0.09 ng/L (tiamulin) to 15.24 μg/L (caffeine); meanwhile, up to 23 pharmaceuticals were detected in sludge samples with concentrations varying from 60 ng/kg (sulfamethizole) to 8.55 mg/kg (ofloxacin). The developed method demonstrated its selectivity, sensitivity, and reliability for detecting multiple-class pharmaceuticals in complex matrices such as municipal wastewater and sludge.  相似文献   

2.
Is our food safe and free of the crisis of antibiotics and antibiotic resistance(AR)?And will the derived food waste(FW) impose AR risk to the environment after biological treatment? This study used restaurant FW leachates flowing through a 200 tons-waste/day biological treatment plant as a window to investigate the fate of antibiotics and antibiotic-resistance genes(ARGs) during the acceptance and treatment of FW. Sulfonamides(sulfamethazine, sulfamethoxazole) and quinolones(ciprofloxacin, enrofloxacin, ofloxacin) were detected during FW treatment, while tetracyclines, macrolides and chloramphenicols were not observable. ARGs encoding resistance to sulfonamides, tetracyclines and macrolides emerged in FW leachates.Material flow analysis illustrated that the total amount of antibiotics(except sulfamethazine) and ARGs were constant during FW treatment processes. Both the concentration and total amount of most antibiotics and ARGs fluctuated during treatment, physical processes(screening, centrifugation, solid–liquid and oil–water separation) did not decrease antibiotic or ARGs concentrations or total levels permanently; the affiliated wastewater treatment plant appeared to remove sulfonamides and most ARGs concentrations and total amount. Heavy metals Ni,Co and Cu were important for disseminating antibiotics concentrations and MGEs for distributing ARGs concentrations. Humic substances(fulvic acids, hydrophilic fractions), C-associated and N-associated contents were essential for the distribution of the total amounts of antibiotics and ARGs. Overall, this study implied that human food might not be free of antibiotics and ARGs, and FW was an underestimated AR pool with various determinants. Nonetheless, derived hazards of FW could be mitigated through biological treatment with well-planned daily operations.  相似文献   

3.
Octylphenols, considered as xenoestrogens, mainly exist as 4-tert-octylphenol (OP) in aquatic environments. The high stability and accumulation of OP in aquatic systems have caused endocrine disruption. The OP in surface water in Jinan, China was analyzed by gas chromatography-mass spectrometry (GC-MS) coupled with solid phase extraction (SPE). Water samples were extracted by SPE on a cartridge system containing C-18 as sorbent. To increase sensitivity and selectivity, OP was derivatized to 4-tert-octyl-phenoxy silane. With the use of phenanthrene-d10 as internal standard, the detection limit based on signal-to-noise ratio (S/N = 3) was 0.06 ng/mL. The average recovery was from 84.67% to 109.7%. The precision of the method given as the relative standard deviations (RSD) was within the range 6.24%-12.96%. In the target water samples, the concentrations of OP were as follows: 15.88-71.24 ng/L for Jinxiuchuan Reservoir, 3.850-26.68 ng/L for the city moat, 6.930-41.56 ng/L for Daming Lake, 66.03-474.2 ng/L for Xiaoqing River, 14.66-17.72 ng/L for the Yellow River, and 10.60-26.43 ng/L for Queshan Reservoir. The Xiaoqing River was seriously polluted due to the discharge of wastewater from Jinan. Jinxiuchuan Reservoir had a higher concentration of OP compared with the Yellow River and Queshan Reservoir, which is ascribed to the surrounding human activities. These data are reported for the first time, providing strong support for the control of OP pollution in Jinan.  相似文献   

4.
The ion chromatography combined solid phase extraction (SPE) method was developed for the analysis of low concentration haloacetic acids (HAAs), a class of disinfection by-products formed from chlorination of hospital wastewater. The monitored HAAs included monochloroacetic acid, monobromoacetic acid, dichloroacetic acid, dibromoacetic acid and trichloroacetic acid. The method employed a sodium hydroxide eluent at a flow rate of 0.8 mlmin, electrolytically generated gradients, and suppressed conductivity detection. To analyze the HAAs in real hospital wastewater samples, C18 pretreatment cartridge was utilized to reduce samples' turbidity. Preconcentration with SPE and matrix elimination with treatment cartridges were investigated and found to be able to obtain acceptable detection limits. Linearity, repeatability and detection limits of the above method were evaluated. The detection limits of monobromoacetic acid and dibromoacetic acid were 2.61 μgL and 1.30 μgL, respectively, and the other three acids are ranging from 0.48 to 0.82 μgL under 25-fold preconcentration. When the above optimization procedure was applied to three hospital wastewater samples with different treatment processes in Tianjin, it was found that the dichloroacetic acid was the major compound, and the growth ratios of the HAAs after disinfection by sodium hypochlorite were 91.28%, 63.61% and 79.50%, respectively.  相似文献   

5.
A solvent extraction procedure for the quantitativeextraction of trace levels of methylgermanium species as theirchloride complex has been developed and the extract was determinedby an on-column capillary gas chromatography with a lab-modifiedflame phorometric detector(FPD) using quartz surface-inducedgermanium emission after pentylation with Grignard reaction. Theextracted percentages for TMGe, DMGe and MMGe in a 100-ml 9mol/LHCl aqueous solution by a single extraction with 1 ml hexane are86.6%, 87.4% and 96.2%, respectively. The precision for overallprocedure range from 3.9% to 7.5%. The extraction was found to beindependent of the initial concentration of methylgermanium speciesin the aqueous phase, which typically varied from 0.1 to 10 μg. This method is suitable for most types of environmental samples and, are superior to all hydride generation coupled spectrometric andspectrophotometric methods in terms of selectivity and toleranceability to interference.  相似文献   

6.
Veterinary antibiotics can enter the environment due to the common practice of land application of manure from treated animals. The environmental fate of tetracyclines in swine manure after composting and field application remains largely unknown. This study analyzed the concentrations of tetracyclines in manure, manure-based compost and compost amended soil in selected swine farms from Beijing, Jiaxing and Putian, China to determine the dilution effects of antibiotics when released into the soil environment. The results demonstrate that residues of antibiotics were detected in all samples and chlortetracycline as well as its degradation products should be regarded critically concerning their potential ecotoxicity. Application of manure-based compost to soil could reduce the possible risk posed by antibiotic contamination, but the trigger value of 100 μupg/kg was still exceeded in soil samples (776.1 μupg/kg dw) from Putian City after application of compost. Field studies such as the present one can help to improve the routine administration of antibiotic-containing composted manure.  相似文献   

7.
Accurate on-site determination of arsenic (As) concentration as well as its speciation presents a great environmental challenge especially to developing countries. To meet the need of routine field monitoring, we developed a rapid colorimetric method with a wide dynamic detection range and high precision. The novel application of KMnO4 and CH4N2S as effective As(Ⅲ) oxidant and As(V) reductant, respectively, in the formation of molybdenum blue complexes enabled the differentiation of As(Ⅲ) and As(V). The detection limit of the method was 8 μg/L with a linear range (R2 = 0.998) of four orders of magnitude in total As concentrations. The As speciation in groundwater samples determined with the colorimetric method in the field were consistent with the results using the high performance liquid chromatography atomic fluorescence spectrometry, as evidenced by a linear correlation in paired analysis with a slope of 0.9990-0.9997 (p < 0.0001, n = 28). The recovery of 96%-116% for total As, 85%-122% for As(Ⅲ), and 88%-127% for As(V) were achieved for groundwater samples with a total As concentration range 100-800 μg/L. The colorimetric result showed that 3.61 g/L As(Ⅲ) existed as the only As species in a real industrial wastewater, which was in good agreement with the HPLC-AFS result of 3.56 g/L As(Ⅲ). No interference with the color development was observed in the presence of sulfate, phosphate, silicate, humic acid, and heavy metals from complex water matrix. This accurate, sensitive, and easy-to-use method is especially suitable for field As determination.  相似文献   

8.
Using the ionic liquid(IL)1-octyl-3-methylimidazolium hexafluorophosphate as the extractant and methanol as the dispersion solvent,a dispersive liquid–liquid microextraction method was developed to extract silver nanoparticles(AgN Ps)from environmental water samples.Parameters that influenced the extraction efficiency such as IL concentration,pH and extraction time were optimized.Under the optimized conditions,the highest extraction efficiency for AgN Ps was above 90% with an enrichment factor of 90.The extracted AgN Ps in the IL phase were identified by transmission electron microscopy and ultraviolet–visible spectroscopy,and quantified by inductively coupled plasma mass spectrometry after microwave digestion,with a detection limit of 0.01 μg/L.The spiked recovery of AgN Ps was 84.4% with a relative standard deviation(RSD)of 3.8%(n = 6)at a spiked level of 5 μg/L,and 89.7% with a RSD of 2.2%(n = 6)at a spiked level of 300 μg/L,respectively.Commonly existed environmental ions had a very limited influence on the extraction efficiency.The developed method was successfully applied to the analysis of Ag NPs in river water,lake water,and the influent and effluent of a wastewater treatment plant,with recoveries in the range of 71.0%–90.9% at spiking levels of 0.11–4.7 μg/L.  相似文献   

9.
Tetracyclines(TCs) discharged from livestock wastewater have aroused public concerns due to their pharmacological threats to ecosystems and human health. As an important medium in the wastewater, suspended organic matters(SOMs) play vital roles in antibiotics transport and degradation. However, limited information has been reported in the relevant literature. This study investigated TCs sorption behavior on SOM, withdrawn from swine wastewater. High TCs sorption capacities were detected, with the maximum values ranging from 0.337 to 0.679 mg/g. Increasing p H and temperature led to the decline of sorption capacity. Results from three-dimensional excitation–emission matrix fluorescence spectroscopy and Fourier transform infrared spectrometry revealed that amide and carboxyl groups were the main functional groups for TCs adsorption. The interactions between SOM and TCs were clarified as predominated by hydrogen-bonding and cation-exchange in acid conditions, and electrostatic repulsion in neutral or alkaline conditions. Adsorption kinetics modeling was conducted, and a satisfactory fitting was achieved with the Freundlich equation. These results indicated that the adsorption process was a rather complex process, involving a combination of cation-exchange and hydrogen-bonding. The results will provide a better understanding of the capability of SOM for TCs transport and abatement in the wastewater treatment process.  相似文献   

10.
Mehlich 1(M1), mehlich 3(M3) and CaCl2 DTPA have been used to predict the available micronutrient in soil. However, the forms of micronutrient extractable by these extractants are not known. In the present study, ten soils, collected from five provinces and the capital of China, representing a wide range of chemical and physical properties, were analyzed by sequential extraction to isolate five forms of cobalt and nickel, they are exchangeable, carbonate bound, Fe Mn oxide bound, organically bound and residual forms. The chemical forms extracted by M1, M3 and CaCl2 DTPA were also investigated. The results show strong correlation between the carbonate bound or organically bound forms of Co or Ni and the amounts of extractable by any of the above three extractants. The main forms extracted by these extractants are carbonate and organically bound forms. The ranking of these three extractants for extraction of Co and Ni are M1>M3=CaCl2 DTPA and M1=M3>CaCl2 DTPA, respectively.  相似文献   

11.
不同反胶束体系萃取纤维素酶的条件优化对比研究   总被引:1,自引:0,他引:1       下载免费PDF全文
采用3种不同的表面活性剂双(2-乙基己基)磺基琥珀酸钠AOT、十六烷基三甲基溴化铵CTAB及鼠李糖脂RL)溶于正己醇/异辛烷相构建不同的反胶束体系,并对比研究了不同反胶束体系萃取纤维素酶的优化条件.分别探讨了水相pH值、表面活性剂浓度、离子强度和离子种类对纤维素酶萃取效率的影响.实验结果如下:在实验条件下,AOT、CTAB和RL 3种反胶束体系水相最佳pH值分别为3.0、8.0和3.0;表面活性剂最佳浓度依次为:AOT 23.7mmol/L、CTAB 15mmol/L和RL 2.75mmol/L;水相中NaCl浓度会影响纤维素酶的萃取率,3种表面活性剂构建的反胶束体系萃取纤维素酶的萃取率均随着盐离子浓度的增大而降低;水相中离子种类也会影响纤维素酶的萃取率.比较不同反胶束体系在最佳条件下萃取纤维素酶的最佳萃取率:CTAB>AOT>RL.  相似文献   

12.
为探究一种简单、经济和可靠的微塑料分离提取手段,设立了11种(F1~F11)具有不同体积比的饱和NaCl和饱和NaI溶液的混合溶液,将混合液作为浮选液来提取土壤中的4种类型(聚乙烯,PE;聚苯乙烯,PS;聚氯乙烯,PVC;聚对苯二甲酸乙二醇酯,PET)微塑料,同时对浮选过程进行了改进.结果表明:当单独使用NaCl溶液浮选时,微塑料的总提取率为55.83%,但随着NaI所占体积比的不断增加,微塑料的总提取率基本呈上升趋势,在NaCl:NaI=1:1时总提取率超过了90%,在只有NaI的条件下总提取率高达96.67%;在F1~F11的任意条件下,PE和PS表现为较高的提取率,均超过了86.67%;PVC和PET在单独使用NaCl溶液浮选时提取率极低,在NaCl:NaI=1:1条件下提取率分别为93.33%和90%,接近单独使用NaI溶液浮选时的提取率;F1~F11任意条件下,低密度微塑料PE和PS的提取率之和均高于高密度微塑料PVC和PET的提取率之和,但在F6~F11条件下提取率差值不大.根据提取结果并结合经济成本等多方面因素考虑,建议使用NaCl:NaI=1:1的混合溶液来分离土壤中的微塑料.  相似文献   

13.
三种模拟消化液对土壤重金属的提取性比较   总被引:5,自引:0,他引:5       下载免费PDF全文
李仪  章明奎 《中国环境科学》2012,32(10):1807-1813
为了解不同方法的模拟消化液对土壤重金属提取性的差异性,比较了国际上广泛使用的3种代表性体外消化方法的模拟消化液(SBET, Simple Bioaccessibility Extraction Test;PBET, Physiologically-Based Extraction Test;SGET, Simple Gastrointestinal Extraction Test)对土壤中Cu、Zn、Pb和Cd的溶解效果.结果表明,3种方法的模拟消化液对土壤重金属的提取效果存在显著的差异.其中,3种模拟消化液对土壤中Zn和Cd的提取能力顺序为SBET>PBET>SGET;当胃液消化物进入肠液后,土壤中Zn、Cd和Pb在PBET及SGET中的溶解度都显著降低,而对于Cu,由于消化酶(胃蛋白酶、胰液素和胆汁盐)的络合作用,其在肠液中的溶解度不一定低于相应的胃液,因此土壤中Zn、Pb和Cd在胃液中的溶解度代表其在消化道中能被吸收的最大值,即其有可能被人体吸收的最大量.所以出于预防和保护的目的,在土壤重金属污染健康风险评价中可用只含有胃液的模拟消化液(如SBET法)评估土壤Zn、Cd和Pb的生物可接受性,但胃液中的提取量并不一定能代表土壤Cu在消化道中能被吸收的最大值,建议使用由胃液和肠液组成,且添加了相应消化酶的模拟消化液(如PBET法)对其生物可接受性进行评估.  相似文献   

14.
微囊藻毒素的提取和提纯研究   总被引:13,自引:0,他引:13  
对采自云南滇池水华蓝藻细胞中的微囊藻毒素 (Microcystins,MCs)的提取与提纯方法进行了研究 .结果表明 ,在藻细胞干重浓度为 2 0g·L-1下 ,与不同甲醇浓度提取液相比 ,4 0 %甲醇溶液可以最有效地从藻细胞中提取出MC RR和MC LR .将MCs提取液过Waters固相萃取小柱后 ,用 70 %甲醇溶液洗脱吸附于柱上的MCs ,可以分别获得 7 3%和 3 5 %纯度的MC RR和MC LR .通过观察洗脱液的颜色变化 ,收集蓝绿色和橘黄色后面流出的基本无色的洗脱液 ,可以获得纯度为 2 8 6 %和12 9%的MC RR和MC LR .  相似文献   

15.
In order to investigate the adsorption mechanism of trace metals to surficial sediments (SSs), a selective extraction procedure was improved in the present work. The selective extraction procedure has been proved to selectively remove and separate Fe, Mn oxides and organic materials (OMs) in the non-residual fraction from the SSs collected in Songhua River, China. After screening different kinds of conventional extractants of Fe and Mn oxides and OMs used for separation of heavy metals in the soils and sediments, NH2OH .HCl (0.1 mol/L) + HNO3 (0.1 mol/L), (NH4)2C2O4 (0.2 mol/L) + H2C2O4 (pH 3.0), and 30% of H2O2 were respectively applied to selectively extract Mn oxides, Fe/Mn oxides and OMs. After the extraction treatments, the target components were removed with extraction efficiencies between 86.09%--3.36% for the hydroxylamine hydrochloride treatment, 80.63%- 101.09% for the oxalate solution extraction, and 94.76%-102.83% for the hydrogen peroxide digestion, respectively. The results indicate that this selective extraction technology was effective for the extraction and separation ofFe, Mn oxides and OMs in the SSs, and important for further mechanism study of trace metal adsorption onto SSs.  相似文献   

16.
通过正交实验,研究了超声破碎法和低温高压破碎法提取一氧化氮还原酶(nitric oxide reductase,nor)的活性,分析了超声强度和次数,破碎压力和次数,裂解液的添加量等因素对于胞内可溶性蛋白和核酸(DNA)的释放与提取nor活性的影响.根据活性污泥中酶的催化特性以及其他实验条件,完善了nor催化活性的测定方法.结果表明超声法提取nor的参数应设定为,超声次数为100次,超声强度为500W,裂解液的添加量为0.1mL.低温高压破碎法提取nor的参数应设定为破碎次数为4次,破碎压力为50MPa,裂解液的添加量为0.1mL.低温高压破碎法下的胞内可溶性蛋白和DNA的释放量与nor的最大催化活性要高于超声破碎法.此外,在nor催化活性的测定方法中,nor活性测定终点时间应为15min.  相似文献   

17.
采用温和加热法、超声法、超声+振荡法和离心法4种方法提取硝化污泥松散结合型胞外聚合物(LB-EPS),及乙二胺四乙酸(EDTA)法、甲醛+NaOH法、甲醛+超声、阳离子树脂法(CER)和加热法提取硝化污泥紧密结合型胞外聚合物(TB-EPS),通过化学分析结合三维荧光(3DEEM)光谱对各提取方法进行比较.结果表明,LB-EPS和TB-EPS的最优提取方法分别为温和加热法和甲醛+Na OH法,TOC提取量分别为16.82、58.43 mg·g~(-1).三维荧光光谱显示温和加热法能有效提取LB-EPS中的类色氨酸和类腐殖酸;甲醛+NaOH法、CER和加热法提取的TBEPS中物质最为全面,主要包括类色氨酸、类腐殖酸和类酪氨酸.TB-EPS三维荧光浓度效应分析表明荧光峰位置与EPS浓度变化无关;类腐殖酸和类酪氨酸荧光峰强度随EPS浓度降低而减小,分别呈二项式和对数关系.  相似文献   

18.
基于质量守恒与流体达西定律推导水气二相流动的连续性微分方程,进而结合饱和度~相对渗透率~毛细压力耦合关系构建二相流动数学模型,并建立多孔介质孔隙度变化与水气二相饱和度之间的数学关系,最终实现多孔介质扰动时空变化的定量表征.案例模拟分析结果表明:对于特定场地而言,抽提影响带的空间形态与抽提真空度密切相关,抽提真空度越大,影响半径及影响带内的气流速度越大,本案例中抽提真空度在11kPa和31kPa时的抽提影响半径分别达到8.5m和9m;在抽提过程中,孔隙度及渗透率随时间呈现先增加后稳定的显著变化,达到稳定所需的时长及其变幅则与离抽提段的空间距离成反相关,抽提压力为0.7′105Pa、特征参数 =0.8的情景模拟显示:距离抽提段1m的P1点在约40min后孔隙度达到稳定、增幅为0.0387,而较远的P4点,距抽提段水平距离为3m,约在60min后达到稳定、增幅为0.0031,相应地,P1和P4点介质渗透率分别从1.18×10-11m2增加至2.22×10-11与1.25×10-11m2;在相同抽提压力下,孔隙度增幅与关键参数 值成正相关,抽提压力为0.9×105Pa、 =0.1和0.8时的孔隙度最大增幅分别约为0.009和0.055;相同参数 条件下,孔隙度增幅与抽提压力成正相关, =0.8、抽提压力为0.7×105Pa时的孔隙度最大增幅则达到0.066.  相似文献   

19.
好氧/厌氧污泥胞外聚合物(EPS)的提取方法研究   总被引:43,自引:2,他引:43  
采用5种方法对同一污泥在好氧和厌氧条件下的胞外聚合物(EPS)进行了提取试验研究.结果表明,甲醛-NaOH和H2SO4法对EPS的提取产量最高,分别为232·0mg·g~(-1)和159·7mg·g~(-1),且无大量细胞自溶发生,是比较有效的提取方法;与对照方法相比较,阳离子交换树脂(CER)和戊二醛提取法却存在严重缺陷.两种氧环境条件下污泥EPS中蛋白质的含量均最高,占EPS总量的50%~80%;其次为胞外多糖和DNA.污泥在经由好氧环境到厌氧环境的转变过程中,EPS中主要成分蛋白质和DNA含量降低较为明显,其厌氧/好氧状态下的相应含量比值为0·59~0·91.试验中也发现,提取步骤和检测手段对结果的影响最大.  相似文献   

20.
采用超声辅助分散液液微萃取结合气相色谱(UAE-DLLME-GC-ECD)检测了污泥中6种氯苯化合物.用丙酮作为萃取污泥样品中氯苯的萃取剂,通过改变萃取剂类型和用量、超声时间以及离子强度等影响因子的实验,确定了最优条件的关键性控制参数.结果表明,6种氯苯的相关系数r2=0.9993~0.9999,相对标准偏差RSD=3.2%~4.4%,检测限LOD为0.001~0.2μg/kg,对造纸、印染和市政3种污泥样品检测的回收率分别为89.2%~103.8%,94.5%~112.1%和89.1%~104.3%.该方法检测污泥中的氯苯不仅具有快速、灵敏和重复性好的特点,而且相对于传统方法,可以节省大量对人体有毒害作用的有机溶剂和分析时间.  相似文献   

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