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1.
将新型荧光探针PTAID以固态形式用于检测土壤中的钯离子(Pd2+)和铜离子(Cu2+),检出限分别为 0.63 和1.19 μmol/L,说明探针PTAID对Pd2+ 和Cu2+有很高的灵敏度。通过条件优化实验,说明探针PTAID在pH值为4.0~12.0,反应时间为0~15 min内可以快速检测Pd2+和Cu2+。对土壤样品中的Pd2+和Cu2+进行检测,该方法与电感耦合等离子体发射光谱法相比,准确度和精密度均较高,具有响应时间短、灵敏度高、选择性好等优点,在土壤重金属检测方面具有广阔的应用前景。  相似文献   

2.
合成了1种基于香豆素和嘌呤衍生物的高效且易于制备的荧光探针CMP,并对该探针检测土壤中的钴离子(Co2+)相关性能进行测试。实验结果表明,探针CMP在4-羟乙基哌嗪乙磺酸(HEPES)缓冲溶液(pH 值=7.4)中对Co2+表现出高灵敏度、高选择性和快速响应(<1min),且一旦与Co2+结合后,可以观察到探针CMP溶液的颜色从黄色变为粉红色。探针CMP检测Co2+的最佳pH值为7.0~11.0。通过荧光滴定实验,计算出探针CMP的检出限为0.26 mg/kg。对土壤和沉积物标准样品进行测定,测定结果均在标准值范围内,相对标准偏差(RSD)为1.3%~2.7%,具有较高的准确度和精密度。该方法具有高选择性和高灵敏度,适用于高效、快速、准确地检测土壤中Co2+。  相似文献   

3.
建立了可同时分析饮用水中铁、铜、镍、锌、钴、镉、锰等过渡金属离子的方法。优化后的离子色谱条件:选用 Dionex IonPac CS5A色谱柱(4 mm×250 mm),以7.0 mmol/L 吡啶-2,6-二羧酸+66 mmol/L KOH+74 mmol/L HCOOH+5.6 mmol/L K2SO4为淋洗液,流速为1.2 mL/min,柱温为30 ℃;以0.5 mmol/L 4-(2-吡啶偶氮)间苯二酚+1.0 mol/L 2-二甲醇胺+0.5 mol/L氨水+0.3 mol/L NaHCO3为衍生液,流速为0.7 mL/min,紫外检测器波长为520 nm。结果表明,该离子色谱柱对以上过渡金属具有很好的保留和分离效果,衍生后的紫外检测手段具有优异的灵敏度和选择性。该方法稳定性良好,连续进样5针的相对标准偏差均小于0.79%;标准曲线线性关系良好,r≥0.998 8;方法检出限低,Fe3+为0.8 μg/L,Fe2+为4 μg/L,Cu2+为0.8 μg/L,Ni2+为3 μg/L,Zn2+为2 μg/L,Co2+为0.9 μg/L,Cd2+为16 μg/L,Mn2+为6 μg/L;检测结果准确,低、中、高3个水平的加标回收率均大于91.5%。该方法适用于环境水体中过渡金属离子的定量分析。  相似文献   

4.
以硫酸铵-氨水溶液为淋洗液,二苯碳酰二肼为柱后显色剂,采用离子色谱-柱后衍生可见光检测环境空气中六价铬和废气中铬酸雾的含量。通过对分析条件的优化,建立了简便、灵敏、选择性好、准确性高和重现性好的分析气体中六价铬的方法。该方法在Cr6+浓度1.00~600 μg/L之间线性良好,当采集50 L有组织废气和20 L无组织废气时,铬酸雾分析的检出限分别为2.2×10-5和1.1×10-5 mg/m3,采集64 m3环境空气时,Cr6+分析的检出限为7.8×10-9 mg/m3,以浸提后的样品水溶液连续进样得到其相对标准偏差为1.42%(n=8)。利用该法进行环境空气中六价铬和废气中铬酸雾的测定,回收率在80%~105%之间。监测结果显示:环境空气中六价铬含量处于极低状态;五金厂厂界废气中铬酸雾含量极低,约为5 μg/m3;五金厂废气排气筒监测的气体中则含有较高浓度的铬酸雾,其含量已经超过GB 21900—2008中规定的排放限值。  相似文献   

5.
为了探究南京市细颗粒物(PM2.5)中金属元素的污染特征及健康风险,利用在线多金属分析仪采集并分析了2022年南京市PM2.5中10种金属元素的质量浓度,利用正定矩阵因子分解(PMF)模型进行金属元素的来源解析,并采用健康风险评价方法对其中5种重金属元素进行健康危害评估。结果表明,10种金属元素总的年均质量浓度为941.3 ng/m3,占PM2.5年均质量浓度的3.4%;其中,铁(Fe)、钾(K)、锌(Zn)3种金属年均质量浓度占比为91.2%。来源解析结果表明,污染物主要来源于土壤尘、燃煤、秸秆焚烧及烟花爆竹燃放、机动车尾气排放及机械磨损。健康风险评价结果表明,锰(Mn)、钒(V)、镍(Ni)、砷(As)4种重金属元素的危害商(HQ)均<1,均不存在非致癌风险;Ni、铅(Pb)的致癌风险(ECR)均<10-6,风险可控;As的致癌风险介于10-6 ~ 10-4之间,存在一定致癌风险。  相似文献   

6.
分别于2013年10月和2014年2月、5月、7月在贵阳市城区3个环境空气质量监测国控点位(南明区市监测站、云岩区黔灵公园马鞍山和观山湖区贵阳一中)进行PM10、PM2.5样品采集,并对10种水溶性离子(SO42-、NO2-、NO3-、NH4+、Cl-、F-、Na+、K+、Mg2+、Ca2+)的含量进行了分析。结果表明,研究时段内,贵阳市3个点位PM10、PM2.5平均质量浓度分别为(64.8±25.5)、(46.6±21.2)μg/m3。其中,云岩区黔灵公园马鞍山点位的颗粒物浓度最低,南明区市监测站点位最高。3个点位PM2.5平均浓度与PM10平均浓度的比值为0.719,表明贵阳市城区PM10中,PM2.5占主导地位。水溶性离子分析显示,SO42-、NO2-、NO3-、NH4+、Cl-、F-、Na+、K+主要分布在PM2.5中,Mg2+、Ca2+主要分布在PM10中。3个点位PM10和PM2.5中的水溶性离子均表现为SO42-、NH4+、Ca2+浓度较大,F-、NO2-较小,表明3个点位的污染源总体相同,且水溶性离子占PM10、PM2.5含量的比例达33.6%~48.1%。贵阳市城区大气中的SO2转化率在5月、7月、10月较高,2月最低,主要是由于5月、7月、10月的高温、高湿、强辐射环境条件促进了SO2向SO42-的转化。阴阳离子平衡分析表明,贵阳市城区PM10、PM2.5呈现出偏碱性的特征。水溶性离子主成分分析表明,贵阳市城区PM10中的水溶性离子主要来源于城市扬尘、生物质燃烧尘、煤烟尘、建筑尘以及二次粒子,PM2.5中水溶性离子的来源与PM10较为相似。  相似文献   

7.
将分子印迹技术与电化学传感器相结合,以双酚A(BPA)为模板分子,吡咯为功能单体,在基于多壁碳纳米管修饰的玻碳电极表面制备了一种对BPA具有选择性识别的分子印迹聚合物,并进行相关试验条件的优化。在最优条件下构建了BPA-MWCNTs-COOH分子印迹电化学传感器,以铁氰化钾K3[Fe(CN)6]为电化学探针,测得BPA在0.01μmol/L~17μmol/L范围内线性良好,检出限为0.006μmol/L。将该方法用于湖水样品测定,结果为未检出,加标回收率为97.8%~115%,RSD <5%。  相似文献   

8.
对上海市嘉定区饮用水源地水中重金属污染物进行了调查研究,并应用美国环保署推荐的健康风险模型对其作了健康风险初步评价。结果表明,重金属致癌物质所引起的健康危害较高,镉、铬、砷的平均个人年风险等级分别为10-7a-1、10-5a-1、10-5a-1,铬、砷的年均风险值非常接近国际辐射防护委员会(ICRP)推荐的最大可接受风险水平,致癌风险极大,应优先控制;非致癌物质所引起的健康风险较小,平均个人年风险大小次序为铅、铜、锌、汞,风险值在10-11~10-9 a-1之间,远低于ICRP推荐的最大可接受风险水平。  相似文献   

9.
对粤北某离子吸附型稀土矿24个土壤样品中的As、Cd、Cr、Cu、Mn、Ni、Pb、Zn和Hg,以及15个地表水样品中的As、Cd、Cu、Hg、Mn、Pb和Zn进行了检测,并以多元统计分析与土壤潜在生态风险指数法、地表水健康风险评价模型相结合的方式,研究了重金属的分布特征及风险水平。结果表明:在土壤中,Mn、Zn、Cd和Pb的平均含量均超过了背景值;Mn、Cr、Ni、Cu、Cd和Zn在采区有较明显集聚,As、Pb和Hg的高含量分布相对均匀;Cr、Ni、Cu和Pb含量主要受区域背景影响,Zn、As、Cd和Hg含量与矿区人类活动关系密切,Mn含量受自然和人为因素共同控制;重金属造成的土壤潜在生态风险整体处于轻微水平,Ⅱ采区和Ⅶ采区生态风险较高;Cd和Hg是造成土壤生态危害的主要重金属元素。在地表水中,Mn的平均浓度超过了《地表水环境质量标准》(GB 3838-2002)规定的限值,其余重金属的含量均满足该标准中的Ⅲ类水质要求;重金属浓度在靠近采区及位于河流中下游的位置偏高;Mn、Cd、Pb、Zn和Cu浓度受稀土开采影响较大,As、Hg浓度主要受自然因素影响;重金属产生的健康总风险(9.39×10-7~1.01×10-6 a-1)低于国际辐射防护委员会推荐的参考标准(5×10-5 a-1),但儿童通过饮水途径受到的健康风险(1.01×10-6 a-1)略超过部分机构的推荐限值;Cd和As是地表水中产生健康风险的主要重金属元素。综上,研究区重金属污染风险管理的主要对象是Cd和Mn。  相似文献   

10.
为了解山西省运城市大气细颗粒物(PM2.5)中重金属的污染特征和来源及其健康风险,于2020年10月15日—2021年2月14日对运城市大气PM2.5样品进行连续采集,使用微波消解-电感耦合等离子质谱法(ICP-MS)分析了样品中的铬(Cr)、锰(Mn)、镍(Ni)、铜(Cu)、锌(Zn)、砷(As)、镉(Cd)和铅(Pb)等8种重金属元素的质量浓度。结果表明,采样期间,ρ(PM2.5)平均值为78.96μg/m3,采暖季ρ(PM2.5)为(79.84±43.79)μg/m3,高于非采暖季(76.54±23.97)μg/m3,采暖季和非采暖季ρ(PM2.5)均值均超过《环境空气质量标准》(GB 3095—2012)中的二级标准。富集因子法分析表明,Ni、Cu、Zn、As、Cd和Pb的富集因子均高于10,其中Cd元素的富集因子平均值达到1.089,表明受人为污染影响严重。主成分分析结果表明,运城市区秋冬季大气中重金属主要有3个来源,分别为混合燃烧源、机动车尾气源、工业排放源。健康风险评价结果显示,经手口摄入暴露强度最大,呼吸吸入暴露强度最小,皮肤接触暴露强度居中;儿童在3种暴露途径的总暴露剂量高于成人,儿童重金属暴露风险高于成人。各途径的非致癌风险强度叠加值<1,表明非致癌风险较小;但As、Pb的非致癌风险相对较高。4种重金属的呼吸吸入途径致癌风险程度排序为:As>Cr>Cd>Ni,单种重金属的致癌风险(TR)值以及重金属的总致癌风险(R)值均<10-6,表明本研究中重金属不具有致癌风险。  相似文献   

11.
An important research area in life sciences is devoted to modeling, prediction, and dynamics of gene-expression patterns. As clearly understood in these days, this enterprise cannot become satisfactory without acknowledging the role of the environment. To a representation of past, present, and most likely future states, we also encounter measurement errors and uncertainties. This paper surveys and improves recent advances in understanding the foundations and interdisciplinary implications of the newly introduced gene–environment networks, and it integrates the important theme of carbon dioxide emission reduction into the networks and dynamics. We also introduce some operational and managerial issues of practical working and decision making, expressed in terms of sliding windows, quadrants (modules) of parametric effects, and navigating (controlling) between such effects and directing them. Given data from DNA microarray experiments and environmental records, we extract nonlinear ordinary differential equations that contain parameters that have to be determined. For this, we employ modern (Chebychevian) approximation and (generalized semi-infinite) optimization. After this is provided, time- discretized dynamical systems are studied. A combinatorial algorithm with polyhedra sequences allows to detect the region of parametric stability. Finally, we analyze the topological landscape of gene–environment networks with its structural (in)stability. By embedding as a module and investigating CO2 emission control and figuring out game theoretical aspects, we conclude. This pioneering work is theoretically elaborated, practically devoted to health care, medicine, education, living conditions, and environmental protection, and it invites the readers to future research.   相似文献   

12.
微波消解-原子吸收光度法测定土壤中铜锌铅镉镍铬   总被引:25,自引:5,他引:25       下载免费PDF全文
用微波消解-原子吸收光度法测定土壤中铜,锌,铅,镉,镍和铬。通过硝酸-氢氟酸-过氧化氢体系消解液对土壤样品消解,选择出微波最佳消解条件。对硝酸-盐酸-过氧化氢体系消解液和硝酸-氢氟酸-过氧化氢体系消解液进行消解对比试验,发现前者不能将土壤样品完全消解,后者能将样品消解完全,但需将消解液中剩余的酸赶尽,否则测定结果将明显偏低。微波消解土壤与传统电热消解相比,操作简便快速,可提高工作效率。  相似文献   

13.
The aim of the study was to determine the extent of heavy metal pollution in the vicinity of a lead battery manufacturing plant in the Czech Republic, both in the general environment and within homes. Topsoils (0–5 cm) were sampled from 100 sites along 4 transects which crossed the battery factory, the town centre and outlying rural areas. Housedust samples were collected from 15 plant-workers' homes and 15 non plant-workers' homes located at various distances from the factory. Samples were analysed for levels of Pb, Zn, Cd, Cu, As and Sb, using ICP-AES. Soil concentrations of Pb, Cd, As and Sb peaked at the perimeter fence of the battery factory with Pb levels of up to 12 650 g g> -1. Concentrations of these metals decreased exponentially within 500 m of the plant. Whilst the battery factory does appear to be a source of all the metals with the exception of Zn, emissions do not appear to be transported to any great extent over distances of more than 0.5 km. Topsoil and housedust concentrations of Pb, Zn, Cd, Cu, As and Sb in the general Mlada Boleslav area do not appear to be significantly different from those recorded in a large scale survey of urban soils in the United Kingdom. A comparison of housedust Pb concentrations in homes of plant workers and non-plant workers suggests that there may be a small input of Pb into the home environment by battery plant employees.  相似文献   

14.
The San Francisco Estuary Regional Monitoring Program for Trace Substances (RMP) began in 1993 and is sponsored by 74 local, state, and federal agencies and companies through their discharge or Bay use permits. The RMP monitors water, sediment, toxicity, and bivalve bioaccumulation at 25 sites in the Bay that are considered to represent "background" conditions. Several major environmental issues have been identified by the RMP. Polychlorinated biphenyls and mercury were often above water quality guidelines, and often occurred in fish tissues above U.S. Environmental Protection Agency (U.S. EPA) screening values. Concentrations do not appear to be decreasing, suggesting continuing inputs. Episodes of aquatic toxicity often occurred following runoff events that transport contaminants into the Bay from urbanized and agricultural portions of the watershed. Sediment toxicity occurred throughout the Bay, and has been correlated with concentrations of specific contaminants (chlordanes, polynuclear aromatic hydrocarbons) at some locations; mixtures of contaminants were probably also important. Since the RMP does not monitor all ecosystem components, assessments of the overall condition of the Bay cannot be made. However, in terms of contamination, the RMP samples suggest that the South Bay, and North Bay sites are moderately contaminated.  相似文献   

15.
A migratory population of 78 pairs of Osprey (Pandion haliaetus) nesting along the Willamette River in westernOregon was studied in 1993. The study was designed to determinecontaminant concentrations in eggs, contaminant concentrationsin fish species predominant in the Ospreys diet, andBiomagnification Factors (BMFs) of contaminants from fish specieseaten to Osprey eggs. Ten Osprey eggs and 25 composite samplesof fish (3 species) were used to evaluate organochlorine (OC)pesticides, polychlorinated biphenyls (PCBs), polychlorinateddibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans(PCDFs). Mercury was also analyzed in fish. Geometric meanresidues in Osprey eggs were judged low, e.g., DDE 2.3 g g-1 wet weight (ww), PCBs 0.69 g g-1, 2,3,7,8-TCDD 2.3 ng kg-1, and generally well below known threshold values for adverse effects on productivity, and the population was increasing. Osprey egg residue data presentedby River Mile (RM) are discussed, e.g., higher PCDDs were generally found immediately downstream of paper mills and eggsfrom the Willamette River had significantly elevated PCBs and PCDDs compared to reference eggs collected nearby in the CascadeMountains. Prey remains at nest sites indicated that the Largescale Sucker (Catostomus macrocheilus) and NorthernPikeminnow (Ptychocheilus oregonensis) accounted for an estimated 90.1% of the biomass in the Osprey diet, and composite samples of these two species were collected from different sampling sites throughout the study area for contaminant analyses. With the large percentage of the fishbiomass in the Osprey diet sampled for contaminants (and fisheaten by Ospreys similar in size to those chemically analyzed),and fish contaminant concentrations weighted by biomass intake, a mean BMF was estimated from fish to Osprey eggs for the largeseries of contaminants. BMFs ranged from no biomagnification(0.42) for 2,3,7,8-TCDF to 174 for OCDD. Our findings for themigratory Osprey were compared to BMFs for the resident HerringGull (Larus argentatus), and differences are discussed. Webelieve a BMF approach provides some basic understanding ofrelationships between contaminant burdens in prey species offish-eating birds and contaminants incorporated into their eggs,and may prove useful in understanding sources of contaminants inmigratory species although additional studies are needed.  相似文献   

16.
In this article a comprehensive approach for the evaluation of possible health effects in an environmental impact assessment (EIA) is described, illustrated with the example of Amsterdam Airport Schiphol. Unlike many EIAs, we estimated quantitatively the impact of aircraft-related pollution in terms of the number of affected people for aircraft noise annoyance, odour annoyance and hypertension. In addition, an analysis of health registry data on cardiovascular and respiratory diseases and a short survey on annoyance and risk perception were carried out. The scope of a health impact assessment depends on the situation, available knowledge and data, concern in the population about the impact and the number of people concerned. It is important to pay attention to the perception of risks and concerns from all parties involved. Moreover, the results demonstrate that far more people outside the area for which standards apply were affected than inside.  相似文献   

17.
The San Francisco Bay estuary isused by over one million shorebirds during springmigration and is home to several hundred thousandduring the winter. Most shorebird use occurs in thesouthern reach of the estuary (South Bay). Thereduced water circulation and discharge fromindustrial sources in the South Bay are responsiblefor the highest levels of some trace elements in theestuary. Wintering shorebirds have been found to havestrong site fidelity to areas as small as a fewkilometers in the South Bay, which may increase theirexposure to contaminants near local point sources. Inaddition, different shorebird species foraging at thesame site have been shown to have differentcontaminant burdens. Thus, our objectives were totest whether contaminant burdens differed by species,or whether contaminant burdens differed in shorebirdscollected at adjacent sites. We examined thecontaminant profiles of two species of shorebirds,long-billed dowitchers (Limnodromus scolopaceus)and western sandpipers (Calidris mauri) thatforage together at two sites, Hayward and Newark,separated by 8 km in the South Bay. We usedmultivariate analysis of variance tests to compare thecomposition of 14 elemental analytes in their livertissues and estimated their molar ratios of Hg and Se. Composite samples were used for contaminant analysesbecause of the small body size of the shorebirds. Seven elemental analytes (Ag, Ba, Be, Cr, Ni, Pb, V)were below detection limits in a majority of thesamples so statistical analyses were precluded. Inthe measurable analytes (As, Cd, Cu, Hg, Mn, Se, Zn),we found no significant intra-site differences ofcontaminant profiles for the two species. We pooledthe samples to examine inter-site differences andfound significant differences in contaminant profilesbetween shorebirds at the neighboring sites (P = 0.03). Shorebirds at Newark had higher (P < 0.05) concentrations of As, Cd, and Se than those at Hayward. Dowitchers at Newark had concentrations of Hg and Se which were highly correlated (P < 0.003) in a mean molar ratio of 1:19, similar tothat reported in other birds. In the larger dowitcherspecies, we also examined exposure to 20organochlorine compounds. Organic analyses showedthat the dowitchers had been exposed to DDE, PCBs,dieldrin and trans-nonachlor, but with no significantdifferences in concentrations between Hayward andNewark (P > 0.05).  相似文献   

18.
Material Disposal Area G is the primary low-levelradioactive waste disposal site at Los Alamos NationalLaboratory, New Mexico, and is adjacent to Pueblo of SanIldefonso lands. Pueblo residents and Los Alamos scientists areconcerned about radiological doses resulting from uptake of AreaG radionuclides by mule deer (Odocoileus hemionus) andRocky Mountain elk (Cervus elaphus), then consumption ofdeer and elk meat by humans. Tissue samples were collected fromdeer and elk accidentally killed near Area G and were analyzedfor 3H, 90Sr, total U, 238Pu, 239, 240Pu,241Am, and 137Cs. These data were used to estimatehuman doses based on meat consumption of 23 kg y-1. Humandoses were also modeled using RESRAD, and dose rates to deer andelk were estimated with a screening model. Dose estimates tohumans from tissue consumption were 2.9 × 10-3 mSv y-1and 1.6 × 10-3 mSv y-1 from deer and elk, respectively,and RESRAD dose estimates were of the same order of magnitude. Estimated dose rates to deer and elk were 2.1 × 10-4 mGyd-1 and 4.7 × 10-4 mGy d-1, respectively. Allestimated doses were significantly less than established exposurelimits or guidelines.  相似文献   

19.
The draft of the German guideline to calculate automobile exhaust dispersion is explained. It contains a two-stage-system: For first quick estimates the guideline contains the simple models MLuS and STREET. In case these models are not applicable or their results shows concentration levels close to the air quality standards, the more complex models PROKAS_V and MISKAM are recommended. PROKAS_V is a Gaussian plume model, MISKAM is a 3-dimensional microscale non hydrostatic flow model for built-up areas with an Eulerian dispersion model. The guideline comprises cases in rural areas without or with few adjacent buildings as well as urban areas with buildings near the roads. The contribution gives information about the models, typical results and some of the problems showing up presently.  相似文献   

20.
The population counts of hydrocarbon-utilising yeasts weremonitored at six sampling stations in the Benin City municipalarea over a four-week period. Although the population countswere relatively constant in each locality, the highest countsoccurred in areas heavily polluted by domestic and industrialeffluents. A total of thirty-five hydrocarbon-degrading yeastswere isolated from soil at the sampling stations usingn-hexadecane as sole carbon source. The isolates were identifiedas belonging to the genera Candida (27 strains), Endomycopsis (4 strains). All the organisms grew on long-chainn-alkane, kerosene, diesel oil and crude oil but failed to growon short-chain n-alkane, aromatic and alicyclic hydrocarbons.Measurement of growth attributes of the isolates usingn-hexadecane, diesel oil and crude oil as substrates showed thatthe Candida species were better utilizers of hydrocarbonsubstrates relative to Endomycopsis and Schizosaccharomyces species.  相似文献   

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