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1.
通过统计2019年晋江石砻断面水质周报数据,分析该断面水质指标季节变化,并用单因子指数法评价其水质.结果表明:pH值全年变化范围为6.68-7.54,季节均值顺序为秋季<冬季<春季<夏季;DO全年变化范围为5.0 mg/L-9.7 mg/L,春冬季高于夏秋季;1Mn全年变化范围为1.5 mg/L-3.4 mg/L,春夏季略高于秋冬季;NH3-N全年变化范围为0.08 mg/L-0.51 mg/L,表现为春冬季高,夏秋季低;TP全年变化范围为0.042 mg/L-0.169 mg/L,表现为春季最高,夏冬季次之,秋季最低;Cr(Ⅵ)全年稳定在0.002 mg/L.单因子评价法显示,晋江总体符合Ⅲ类水质标准;使用t检验法发现,TP与NH3-N显著相关,可能是由于二者受到相同污染源的影响所致.  相似文献   

2.
HPLC法测定饲料中维生素A、维生素D 3 和维生素E   总被引:2,自引:0,他引:2       下载免费PDF全文
建立了以w(C2H5OH)=95 %乙醇直接提取,高效液相色谱仪在波长280 nm和254 nm处连续测定饲料中维生素A、维生素D3和维生素E的方法.色谱柱为大连依利特Hypersil ODS C18(25 cm×4.6 mm×5 μm),流动相为甲醇-水,流速为1.2 mL/min.维生素A、维生素D3、维生素E的质量浓度分别在1.0 mg/L~20.0 mg/L、0.5 mg/L~15.0 mg/L 、2.5 mg/L~50.0 mg/L范围内与峰面积呈良好的线性关系,检测限分别为0.3×10-6 μg、0.04×10-6 μg、5.0×10-6 μg,相对标准偏差分别为1.6 %、2.7 %、2.4 %,平均回收率分别为99 %、102 %、98 %.  相似文献   

3.
采用消解仪替代高压蒸汽灭菌器消解水样,用麝香草酚分光光度法替代紫外分光光度法测定总氮.试验表明,方法在0mg/L~10.0mg/L范围内线性良好,相关系数R为0.9999;方法检出限为0.04mg/L;测定低、中、高质量浓度的标准溶液,RSD为1.1% ~5.5%;对3份实际水样进行加标回收试验,回收率为94.6% ~98.2%,测定总氮标准品,结果在保证值范围内;用该方法与国标方法同时测定水样,测定结果的相对偏差〈5%.  相似文献   

4.
采用次灵敏线测定地表水中高浓度的钙和镁,标准溶液系列稳定时间长,方法线性范围宽,在钙10.0 mg/L~150 mg/L、镁5.0 mg/L~70.0 mg/L之间线性关系良好,检出限钙为5.0 mg/L,镁为2.5 mg/L,精密度与准确度均符合要求,与国标方法的比对试验表明两种方法可替代使用.  相似文献   

5.
SPE- GC/MS法测定水中对硝基氯苯和2,4- 二硝基氯苯   总被引:2,自引:1,他引:2  
采用SPE-GC/MS法测定水中对硝基氯苯和2,4-二硝基氯苯,优化了试验条件.对硝基氯苯在1.00 mg/L~80.0 mg/L之间线性关系良好,2,4-二硝基氯苯在1.00 mg/L~50.0 mg/L之间线性关系良好,方法检出限对硝基氯苯为0.6 μg/L,2,4-二硝基氯苯为2.1 μg/L,回收率对硝基氯苯为86.2%~94.7%,2,4-二硝基氯苯为87.3%~95.4%.  相似文献   

6.
超声波萃取-红外分光光度法测定土壤中石油类   总被引:1,自引:0,他引:1  
采用超声波萃取-红外分光光度法测定土壤中石油类,并对超声波机的功率、水浴温度和萃取时间进行优化.试验表明:方法在0mg/L~80.0mg/L范围内线性良好,相关系数r为0.9997;方法检出限为6.00μg/L,当取土壤样品10.0g时,方法检出限为0.03mg/kg;空白土壤的加标回收率为97.4% ~103%;测定实际土壤样品的RSD为3.0% ~3.9%.通过比较超声波萃取、四氯化碳热浸法和快速溶剂萃取法的前处理效果,显示出超声波萃取法的优越性.  相似文献   

7.
微波消解-原子荧光法测定土壤中汞、砷、硒   总被引:5,自引:3,他引:5  
建立了微波消解-原子荧光法测定土壤中汞、砷、硒的方法.汞在0.00 μg/L~1.00 μg/L、砷在0.00 μg/L~10.0 μg/L、硒在0.00 μg/L~2.00 μg/L之间线性关系良好,以称样0.200 0 g计,检出限汞为0.005 mg/kg,砷为0.009 mg/kg,硒为0.025 mg/kg.经国家有证标准物质验证,方法精密度与准确度均能满足土壤环境样品的测试要求.  相似文献   

8.
以多孔玻板吸收管采样,采用离子色谱法同时测定作业场所空气中的氟化氢、氯化氢和硫酸,采样效率>92%。氟化氢在0 mg/L~2.00 mg/L、氯化氢在0 mg/L~2.50 mg/L、硫酸在0 mg/L~4.00 mg/L范围内线性良好,检出限分别为0.003 mg/m3、0.02 mg/m3、0.023 mg/m3(按采样体积60 L计),标准溶液平行测定的RSD≤8.0%,两个质量浓度水平加标的平均回收率为92.6%~106%。  相似文献   

9.
高效液相色谱法测定水中4种酰胺类除草剂   总被引:5,自引:0,他引:5       下载免费PDF全文
采用高效液相色谱法同时测定水中4种酰胺类除草剂,优化了试验条件.方法线性关系良好,检出限敌稗为0.000 5 mg/L,乙草胺为0.002 mg/L,丙草胺为0.005 mg/L,丁草胺为0.005 mg/L,RSD≤5.6%,平均加标回收率在84.1%~95.1%之间.  相似文献   

10.
为了解大通湖主要污染物TN、TP和NH3-N的空间分布特征及污染来源,于2017年9月对大通湖及周边河流进行采样分析。结果表明,大通湖周边入湖河流的ρ(TN)为0. 74~2. 18 mg/L,ρ(NH3-N)为0. 094~0. 874 mg/L,ρ(TP)为0. 02~0. 243 mg/L;湖体ρ(TN)为0. 82~1. 47 mg/L,呈现湖体中间低、四周高的特征,ρ(NH3-N)为0. 14~0. 42 mg/L,但整体差异较大,高值区主要在大通湖西南及东部,ρ(TP)为0. 160~0. 289 mg/L,水质为Ⅴ类或劣Ⅴ类,TP为湖体的主要污染物,湖体的ρ(TP)变化呈现出从四周向中部增加的趋势,高值区主要集中在大通湖正南及湖心处;根据2016年大通湖区域污染源统计及入湖污染物计算,大通湖水环境的TP污染负荷大小排序为农田径流畜禽养殖生活污水工业污染网箱养鱼旅游服务。  相似文献   

11.
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:24,自引:5,他引:24       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   

12.
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   

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.
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   

15.
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   

16.
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   

17.
This paper gives mathematical details and sample applications of SWAGMAN Farm (SWAGMAN, Salt Water and Groundwater Management), a farm-scale hydrologic economic model that integrates agronomic, climatic, irrigation, hydrogeological and economic aspects of irrigated agriculture. The model is capable of determining optimum mix of land use to keep watertable and soil salinity within acceptable limits while maximising the economic returns. Alternatively, the model can simulate water and salt balance and economics of a given cropping preference. Web-based and Geographic Information Systems versions of the model are available for integration with the environmental reporting systems of the irrigation areas.  相似文献   

18.
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   

19.
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   

20.
The stable nitrogen isotope ratios of some biota have been used as indicators of sources of anthropogenic nitrogen. In this study the relationships of the stable nitrogen isotope ratios of marsh plants, Iva frutescens (L.), Phragmites australis (Cav.) Trin ex Steud, Spartina patens (Ait.) Muhl, Spartina alterniflora Loisel, Ulva lactuca (L.), and Enteromorpha intestinalis (L.) with wastewater nitrogen and land development in New England are described. Five of the six plant species (all but U. lactuca) showed significant relationships of increasing δ 15N values with increasing wastewater nitrogen. There was a significant (P < 0.0001) downward shift in the δ 15N of S. patens (6.0 ± 0.48‰) which is mycorrhizal compared with S. alterniflora (8.5 ± 0.41‰). The downward shift in δ 15N may be caused by the assimilation of fixed nitrogen in the roots of S. patens. P. australis within sites had wide ranges of δ 15N values, evidently influenced by the type of shoreline development or buffer at the upland border. In residential areas, the presence of a vegetated buffer (n = 24 locations) significantly (P < 0.001) reduced the δ 15N (mean = 7.4 ± 0.43‰) of the P. australis compared to stands where there was no buffer (mean = 10.9 ± 1.0‰; n = 15). Among the plant species, I. frutescens located near the upland border showed the most significant (R 2 = 0.64; P = 0.006) inverse relationship with the percent agricultural land in the watershed. The δ 15N of P. australis and I. frustescens is apparently an indicator of local inputs near the upland border, while the δ 15N of Spartina relates with the integrated, watershed-sea nitrogen inputs.  相似文献   

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