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111.
基于固相萃取-超高效液相色谱-两级串联质谱(SPE-UPLC/MS/MS)技术,建立了制药废水中头孢克洛、头孢曲松、头孢氨苄、头孢噻肟、头孢唑啉、头孢呋辛、头孢西丁、头孢噻吩和头孢拉定共9种头孢类抗生素的测试方法,定量限为27.5~131.8ng/L,目标物回收率为72.8%~102.2%;利用该技术,检测某采用两级生物氧化工艺的制药废水处理厂各级单元出水,共检测出头孢曲松、头孢唑啉、头孢噻肟和头孢呋辛4种头孢类抗生素,其在进水中平均浓度分别为7.6,12.9,5.6,91.6μg/L,在一级氧化出水中平均浓度分别为4.2,5.2,2.2,37.4μg/L,在二级氧化出水中平均浓度分别为2.0,2.7,0.6,24.4μg/L;风险商值法评估制药废水出水中残留的头孢曲松、头孢唑啉、头孢噻肟和头孢呋辛的环境风险均为高风险等级.  相似文献   
112.
黄健  舒增年  张四海 《中国环境科学》2014,34(11):2831-2837
为改善聚醚砜(PES)超滤膜的抗污染性能和提高对腐殖酸(HA)的截留率,以介孔二氧化硅(MS)为添加剂,采用相转化法制备了亲水性PES/MS复合超滤膜,并对膜表面进行荷电改性.研究了MS对膜的断面结构、表面化学性质和过滤性能的影响,考察了荷电改性PES/MS超滤膜对水中HA的分离性能以及溶液pH值、离子强度和钙离子浓度等因素对荷电膜超滤过程的影响.SEM表征结果显示,MS颗粒在PES/MS复合膜的表面分散均匀,膜孔的连通性改善.亲水荷电改性后,膜表面接触角由68°降至57°,zeta电位由-6.31mV降至-11.45mV,膜对HA的去除率由72%提高到95%,通量衰减率由29.8%减小到4.9%.结果表明,对PES超滤膜进行亲水荷电改性可有效提高对HA的截留率,同时减轻膜污染;另外,溶液的pH值、离子强度和钙离子浓度对荷电超滤膜的过滤性能有较大影响,调节合适的溶液环境可在提高截留率的同时,减轻膜污染.  相似文献   
113.
梁钪  牛宇敏  刘景富 《环境化学》2014,(10):1681-1685
建立了超高效液相色谱-串联质谱(UPLC-MS/MS)联用法同时测定污水中14种有机磷酸酯阻燃剂(OPEs)的分析方法.样品采集后,经GF/C膜过滤,HLB固相萃取小柱净化后进样分析.以BEH C18色谱柱为分离柱,乙腈和水混合液为流动相(0.2 mL min-1)梯度洗脱,15 min内可完成14种OPEs的分离.在电喷雾正离子模式下,采用多反应监测模式(MRM)进行质谱测定.在加标浓度为1.0μg·L-1时,14种OPEs在污水处理厂进水和出水中的回收率分别为52.1%—119%、43.6%—114%,相对标准偏差(RSD)分别为1.2%—16.2%、0.4%—9.2%,方法的检出限(LOD)在0.3—6.0 ng·L-1间.方法精密度好,准确度高,可满足同时对污水样品中的14种OPEs进行定性及定量分析的要求.  相似文献   
114.
工业废水对洹河有机污染的调查与分析   总被引:1,自引:0,他引:1  
李烨  杨卫芳  阎波  李劲 《干旱环境监测》2005,19(4):204-206,219
采用适当的样品前处理技术,利用GC/MS对洹河水及焦化厂、染料厂废水进行有机污染物的分析,确定了工业废水对洹河造成有机污染的主要化合物,从而为企业污水的处理和洹河治理提供依据.  相似文献   
115.
It has been reported that the relative response factors of isotopically labeled standards and unlabeled standards of the same perfluorinated compounds could be different. Individual (100 ng mL?1) solutions of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) were analyzed using high-performance liquid chromatography tandem mass-spectrometry under negative-ion electrospray to detect any impurities present down to 0.5%–0.1% relative to the major component. Purity of the standards ranged from approximately 86% to ≥ 97%. Standard solutions of unlabeled and isotopically labeled materials were analyzed to compare the response factors of isotopically labeled analytes versus their nonlabeled counterparts in three different matrices at equivalent concentrations: organic solvent (methanol), serum extract, and water present individually and concurrently. Not all labeled analytes have the same response factor as their nonlabeled complement, and in at least one case the matrix in which the standard is present may cause significant suppression of response. Standard solutions of electrochemical fluorination produced PFOA and PFOS were quantified under multiple reaction monitoring mode, using calibration curves prepared from standards consisting primarily of linear standards only. The use of linear only standards may cause under-prediction of concentrations, and that the working range of these standards may be limited.  相似文献   
116.
An experiment was conducted on freshwater fish Cyprinus carpio to study the effect of the pesticide curacron on total serum protein. Curacron is an organophosphate pesticide and used by the farmers to protect their crops. This pesticide reaches the aquatic ecosystem by direct or indirect means and affects aquatic fauna. LC50 for curacron for C. carpio was calculated by the log-dose/probit regression line method and found to be 0.38?ppm at 96?h. Three sub-lethal concentrations (0.1, 0.01, and 0.001?mL?L?1) were selected to expose the fish for 1, 7, 14, and 21days. Changes in total serum protein were observed at all pesticide concentrations and exposure periods. Total serum protein was decreased from control. At 1 and 7 days, the decrease was quantitative at all concentrations, while at 14 and 21 days, the fall was significant at all concentrations. Hence, human population may be at risk by consuming these contaminated fish.  相似文献   
117.
The habit of khat chewing is widespread with a deep-rooted sociocultural tradition in these regions and as such poses a public health problem. The use of pesticides is considered to be indispensable practice for the production of adequate food supply for the increasing demands by the global population and for control of insect-borne diseases. Thus, contamination of the environment with pesticides and entry of these chemicals into the food chain is unavoidable especially in developing countries. The main objective of our current study was to assess pesticide pollution of khat leaves (unknown origin) obtained while being smuggled into the Kingdom of Saudi Arabia and to be used in Jazan area. A total of 120 khat leaf samples were extracted using solid-phase extraction followed by gas chromatography/mass spectrometry analysis for the presence of 69 standard pesticides using an internal standard, tiphenyl phosphate. No pesticide residues were detected in all the studied samples. These data as preliminary and more experiments need to be performed to confirm our present findings. Routine monitoring of the pesticide residues is important for the prevention, control, and reduction of environmental pollution and also for legal decisions to minimize health risks.  相似文献   
118.
This study concerns the polycyclic aromatic hydrocarbons (PAH's) emission from gasoline and diesel automobile engines.

The sampling procedure, the extraction and the analytical method are presented. Using the gas chromatography‐mass spectrometry technique it is possible to detect and quantify easily about 15 PAH's. Data obtained on exhaust particles collected from gasoline and diesel automobile engines are presented and discussed.  相似文献   
119.
Abstract

Incidents of using naphthalene in olive orchards as a repellent of olive fly (Bactrocera oleae) have recently been recorded. Naphthalene, the primary ingredient of mothballs, is described to be diluted in plastic bottles and hanged on the trees releasing its characteristic odor which is supposed to repel olive fly. Since naphthalene has been characterized as possibly carcinogenic to humans and animals, it was considered essential to monitor olive oils regarding their potential contamination with this specific pollutant. To this goal, a simple, sensitive and reliable analytical method for the determination of naphthalene in olive oil has been developed. The method involves extraction with ethyl acetate: acetonitrile (1:1) and determination of naphthalene using gas chromatography triple quadrupole mass spectrometry. The method was validated in four fortification levels, 0.005, 0.01, 0.05, and 0.1?mg/kg in accordance with the EU requirements. The obtained results were acceptable as far as validation criteria are concerned, given recoveries between 71% and 87% and RSDs between 5% and 24%. The limit of determination for naphthalene was set at 0.005?mg/kg based on the lowest concentration level being validated with acceptable accuracy. The analytical technique was successfully applied to 75 olive oil samples collected from oil mills in Greece and no positive results of naphthalene were detected.  相似文献   
120.
Oleic or linoleic acid supported on barium sulphate was used to remove atrazine and terbuthylazine in the range of 0.1–2.0 μg/L using spiked water samples. The sorption of atrazine depends on the stirring time and the best value is 150 min. Terbuthylazine is removed well with a stirring time of 60 min and its adsorption is about 90%. Detection of the residual pesticide in treated waters, after solid phase extraction (SPE), was carried out by GC‐MS operating in selected ion monitoring (SIM) using a calibration curve by direct injection of standard solutions of herbicide.  相似文献   
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