酸清洗隔断连续流动分析法测定水中总余氯

设计试剂配方和反应模块,采用酸清洗隔断连续流动分析测定水中总余氯,通过优化试验条件,使方法在0 mg/L～2.00 mg/L范围内线性良好,相关系数> 0.999,方法检出限为0.014 mg/L。实际废水样品6次测定结果的RSD为2.2%～7.3%,加标回收率为96.8%～106%。用该方法和国标法同时测定实际废水样及标准溶液,两方法测定结果的相对偏差为1.2%～7.7%。     

过氯乙烯滤膜采样-酸消解-钼蓝光度法测定磷酸雾

建立了过氯乙烯滤膜采样 -酸消解 -钼蓝分光光度法测定磷化车间磷酸雾的监测方法。实验室模拟采样的捕集效率为 95 7%～ 99 1 %。单个实验室对含 5μg和 1 5μg样品进行多次测定 ,其相对标准差小于 5% ,样品加标回收率为 98 2 %～ 1 0 0 5% ,方法检测限为 0 0 0 7mg/m3。对标样测定 ,结果均在给定值范围内。用该法与等离子发射光谱法(ICP)对 5个样品进行比对测定 ,结果均令人满意。     

砷化氢-硝酸银分光光度法测定海水中痕量砷的研究

总结了砷化氢 -硝酸银分光光度法测定海水中痕量 As的分析条件和技术参数 ,提出了测定海水样必须向反应瓶中加入适量消泡剂 ,并给出一种理想的硼氢化钾片剂制备方法。砷含量为 0 .0～ 2 0 .0μg/L的范围内线性良好 ,工作曲线为 y=0 .0 2 2 1x -0 .0 0 0 7,相关系数为 0 .9994,方法检出限为 0 .3 8μg/L ,标准参考物质的测定值与保证值 (A± U )符合良好。大批量海水样品分析空白 Ab<0 .0 15、平行测定合格率为 93 .3 %、加标回收合格率为 89.0 %。     

超高效液相色谱-质谱法直接进样测定水中草甘膦和丁基黄原酸

通过优化色谱条件、稀释样品、加入氨水等措施,建立了超高效液相色谱-质谱法直接进样分析地表水及自来水中草甘膦和丁基黄原酸的方法。草甘膦和丁基黄原酸在各自线性范围内线性关系良好,相关系数(R2) 0. 999。方法检出限分别为5. 20(前处理中对样品进行了20倍稀释)和0. 08μg/L,远低于国家标准限值要求。草甘膦和丁基黄原酸的加标回收率分别为73. 8%～92. 3%和85. 0%～113. 0%,样品间的标准偏差均10%,准确度和精密度均满足质控要求。该方法简化了样品前处理过程,成功降低了基质效应对草甘膦和丁基黄原酸测定的干扰。     

负吸光度法测定微量氟化物

研究了 F- 与茜素磺酸锆的褪色反应条件 ,建立了一种负吸光度法测定微量氟化物的新方法 ,F- 量在 0～ 1 5μg/2 5 ml范围内与负吸光度值呈线性关系 ,方法已用于环境水中微量氟的测定 ,RSD为 0 .2 5 %～ 4 .2 % ( n=5 ) ,回收率为93.1 %～ 1 0 2 .0 %。     

微波消解-ICP/MS法同时测定鱼肉中的砷和汞

采用微波消解处理鱼肉样品,用电感耦合等离子体质谱法测定样品中砷和汞。通过试验优化微波消解参数、酸体系及赶酸温度,用在线加入内标方法消除基体干扰及仪器漂移对测定的影响。方法在0μg/L～40. 0μg/L范围内线性良好,砷和汞的方法检出限分别为0. 002 mg/kg和0. 001 mg/kg,实际样品6次测定结果的RSD为5. 4%～15. 6%,加标回收率为90. 0%～110%。将该方法用于测定芹菜和扇贝标准物质,测定值在标准值不确定度范围内。     

两种前处理方法对液相色谱-电感耦合等离子体质谱法测定土壤中有机汞的比对研究

分别采用酸浸提法和碱消解法作为前处理方法,以液相色谱电感耦合等离子体质谱法(HPLC-ICP-MS)作为测定方法测定土壤中的有机汞(甲基汞、乙基汞和苯基汞),对2种前处理方法进行比对分析。结果表明,采用酸浸提法,3种有机汞的方法检出限为0.5~0.9μg/kg,甲基汞和乙基汞的加标回收率为72.4%~86.4%,相对标准偏差(RSD)均<9.3%,苯基汞的回收率均<40%,RSD为7.4%~10.2%;采用碱消解法,3种有机汞的方法检出限为0.3~0.4μg/kg,加标回收率为60.4%~106%,RSD均<8.6%。碱消解法相较于酸浸提法,具有更高的萃取效率,更好的回收率和重复性。     

2-(2-吡啶偶氮)-5-二甲氨基酚固相萃取光度法测定环境样品中钴(Ⅱ)的研究

根据新试剂2-(2-吡啶偶氮)-5-二甲氨基酚(PADMAP)与钴的显色反应及C18固相萃取小柱对显色络合物的固相萃取,建立了一种测定环境样品中痕量钴的新方法,在pH4 0的HAc—NaAc缓冲介质中,溴化十六烷基三甲基铵(CTMAB)存在下,PADMAP与钴反应生成2∶1稳定络合物,该络合物可用C18固相萃取小柱富集,小柱上富集的络合物用乙醇(内含2%乙酸)洗脱后用光度法测定。络合物最大吸收波长为585nm,摩尔吸光系数为1 05×105L·mol-1·cm-1,钴含量在0—1 0mg/L内符合比耳定律。方法用于几种环境样品中钴的分析,结果令人满意。     

异丙醇增感电感耦合等离子体质谱法直接测定土壤和沉积物中硒

提出了沸水浴混合酸法消解,以异丙醇为增感剂,电感耦合等离子体质谱直接测定土壤和沉积物中硒的方法。实验表明2mol/L硝酸-4mol/L盐酸混酸能有效溶出土壤和沉积物中各种形态的硒。相对于1%硝酸基体,4%(V/V)异丙醇基体中硒的ICP-MS响应值提高了12.1倍;而且4%(V/V)异丙醇基体可有效抑制硒的质谱干扰。ICP发射功率和雾化气流速是影响异丙醇在ICP-MS测定过程增敏效应的主要因素。以78硒为测定同位素,方法检出限为0.005mg/kg,实际样品测定精密度均小于5%。用于测定土壤和沉积物国家标准样品并对其消解液进行加标回收实验,结果令人满意。     

反向流动注射化学发光测定微量甲醛

基于在甲醛存在下 ,高锰酸钾与Fe(Ⅱ )在酸性介质中发生化学发光反应 ,建立了反向流动注射化学发光测定微量的甲醛分析方法 ,该法测定甲醛的线性范围为 5 0× 10 - 7～ 1 5× 10 - 2 g ml,检出限为 3 0× 10 - 7g ml,相对标准偏差为2 5 % (1 5× 10 - 5g ml甲醛 ,n =11)。该法应用于测定空气中微量的甲醛 ,结果令人满意。     

A New Mathematical Approach in Environmental and Life Sciences: Gene–Environment Networks and Their Dynamics

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.      

Topsoil and Housedust Metal Concentrations in the Vicinity of a Lead Battery Manufacturing Plant

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.     

An Overview of Contaminant-Related Issues Identified by Monitoring in San Francisco Bay

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.     

Biomagnification factors (fish to Osprey eggs from Willamette River,Oregon, U.S.A.) for PCDDs,PCDFs, PCBs and OC pesticides

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.     

The Draft of the New German Guideline VDI 3782/8 to Model Automobile Exhaust Dispersion

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.     

An investigation on biological stability of product water generated by lab-scale and pilot-scale distillation systems

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, 240}Pu,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.     

Hydrocarbon Utilization in Yeast Isolates Found to Grow in Association with Petroleum in a Polluted Ultisol of Midwestern Nigeria

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.     

Assessing health consequences in an environmental impact assessment: The case of Amsterdam Airport Schiphol

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.     

Contaminant Profiles of Two Species of Shorebirds Foraging Together at Two Neighboring Sites in South San Francisco Bay, California

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).     

火焰原子吸收光谱法测定苏州开发区26种蔬菜中铜锌铁锰镍

用火焰原子吸收光谱法测定了苏州开发区26种蔬菜中的铜、锌、铁、锰和镍的含量。蔬菜样品用硝酸高氯酸混合酸进行消解。4次测定值的相对标准差<5%,加标回收率在92%～107%之间。26种蔬菜中铜、锌、铁、锰、镍的含量基本均在世贸组织规定的范围内。