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1.
1.实验废水的处理实验废水有多种多样.在制定废水的处理方案时,要同时考虑废水的分类方法.废水分类方法不是一成不变的,而要根据实验废水的变化而作相应的调整.为此应组织各实验室和有关部门共同进行实验废水的种类、数量的调查和测定.在规定实验废水的分类方案时,应注意:以实验废水调查测定的结果为基础;以确定实验废水处理方法为依据,分类方案不应对处理方法产生干扰.确定的处理方法所不能处理的废液(物质)应另列一类,危害性毒性大的物质优先分类或就地处理(就在该实验室.原经手人员就地销毁或进行无害化处理).  相似文献   

2.
序贯数论优化法和侧影图进行河流优化布点   总被引:3,自引:0,他引:3  
运用序贯数论优化法(SNTO)对监测点进行分类,同时根据分类结果,基于样本之间的相似性和差异性,构造一Rousseuw定义的函数并做侧影图,以确定各属类的最佳代表点,从而遴选出优化了的点位.  相似文献   

3.
环境质量评价的生物方法研究   总被引:1,自引:0,他引:1  
环境质量的生物评价是以生物对环境污染的表现为基础的.环境质量评价的生物方法包括环境指示生物的选择,环境质量生物评价指标的确定和环境质量分类等3个步骤.论述了环境污染的生物表现,提出了选择环境指示生物的原则,给出了环境质量生物评价的3类指标,建立了环境质量4级分类体系.  相似文献   

4.
国家重点监控水污染企业筛选方法辨析   总被引:1,自引:0,他引:1  
简述了国家重点监控水污染企业筛选的方法。建议通过增加筛选因子,拓宽统计范围,采用分类筛选的方式改进国家重点监控企业筛选方法,并由环境监察、税务和工商等部门联合确定国家重点监控企业名单。  相似文献   

5.
针对固定观测站采集的序列图像中光照变化和背景复杂的问题,将图像序列作为图像在时间维的拓展,提出一种结合颜色空间变换和神经网络的目标分类方法,以辽河口湿地为例开展实地观测试验。基于前期现场调查得到的地物分布信息,将序列图像转换至HSV空间,选择像素小区域作为样本训练多层神经网络,获得更高维度分类依据映射,并完成潮滩生态监测区域目标分类及重要湿地植物翅碱蓬的分布信息提取。对提取结果进行定量验证,该方法整体精确率稳定在90%左右。  相似文献   

6.
搞好水污染事故监测,对于促进污染源的治理,保护水域生态环境,促进社会稳定,保证经济持续稳定发展有着极其重要的意义.但水污染事故的现场监测难度较大,其监测结果,又是事故处理的依据,如何及时、准确地确定水污染事故的污染物和污染源,乃水污染事故现场监测的关键.一、必须及时确定污染物首先,对水污染事故的监测要立即进行.由于水体是一个错综复杂的动态系统,  相似文献   

7.
针对热解焚烧技术处置医疗废物的特点,分析处置工艺运行参数对稳定工况的影响规律,确定医疗废物在热解焚烧技术炉内稳定焚烧的工艺参数,指出送风量与气化炉、燃烧炉的温度关系是焚烧系统控制的关键。通过对某型焚烧炉的测试,得到了送风量与气化炉和燃烧炉的温度关系曲线。测试结果表明,实时动态调控气化炉和燃烧炉的送风量,能够实现医疗废物的稳定焚烧。  相似文献   

8.
河流健康评估单元划分是开展河流健康评估和生态系统保护的重要基础,可以揭示河流生态系统健康状况的空间特征差异。构建了河流健康评估单元的划分标准和方法,并以抚河为研究对象,通过水环境监测点样本聚类分析和相关性分析,甄别划分河流健康评估单元的关键指标,合理确定河流健康评估单元的划分标准,科学划分抚河健康评估单元。研究结果显示:(1)抚河水环境监测初始布局共布设40个监测点,分为7类,优化后的监测点数量减少为16个;(2)各水环境监测指标中,叶绿素a与监测点分类结果之间的相关系数为0.944,并在0.01水平上显著相关,由此确定叶绿素a为抚河健康评估单元划分的关键指标;(3)以叶绿素a的浓度(mg/m~3)为分区指标,确定抚河健康评估单元的分区标准为(0,5)、[5,8)、[8,11)、[11,14)、[14,18)、[18,24)、[24,+∞);(4)抚河共分为16个健康评估单元,每个评估单元包含至少1个监测点,其中,相水源头区和相水干流两个相邻健康评估单元所包含的水环境监测点属于同一分类,其他相邻分区所含监测点均属于不同分类,表明所构建的河流健康评估单元划分方法具有一定的合理性和适用性。  相似文献   

9.
利用单颗粒气溶胶质谱仪(SPAMS)于2018年1月1日—2019年12月31日对上海市浦东新区环境空气PM2.5开展高时间分辨化学成分监测。结果表明,2019年监测点空气质量总体优于2018年,AQI达标率由74.8%升高至86.6%。通过对PM2.5成分分类,最终确定了8类颗粒物,相较于2018年,2019年富钾颗粒物升幅较为明显,左旋葡聚糖、重金属和元素碳有小幅增加,其余各组分相对减少。对PM2.5排放源分类分析显示,机动车尾气源占比>25%,其中2018年3月、2018年7月、2019年2和3月贡献超过40%;二次无机源和燃煤源呈现一定的季节变化特点,整体秋冬季高于春夏季,2019年燃煤源占比较2018年下降了41%;工业排放源2018年5和10月、2019年1和5月占比相对较高,其余各月份占比相对较为稳定。  相似文献   

10.
利用国家环保部标准样品研究所已知标准气体,选取绵阳市的三个城市空气自动监测站进行二氧化硫实验分析。结果表明,EC9850B二氧化硫监测仪跨漂后仪器响应快速升至最高值然后逐渐升高趋向稳定,通过连续跨漂的监测数据与已知标准气体的符合性确定仪器跨漂35min后基本稳定,并在标准气体中值附近波动,据此开始记录数据,准确度高,数据有效且质量可控。  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: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   

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.
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   

17.
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   

18.
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   

19.
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   

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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