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901.
乙酰丙酮分光光度法测定水中甲醛时影响空白值的因素   总被引:2,自引:0,他引:2  
针对水质中甲醛测定时试剂水、pH值、乙酰丙酮试剂、加热温度和显色时间等影响因素进行了讨论,并提出了减小空白值的对策.  相似文献   
902.
固相微萃取-气相色谱法测定水中痕量有机氯农药   总被引:4,自引:0,他引:4  
建立了固相微萃取-气相色谱联用快速测定水中14种痕量有机氯农药的方法,对比研究了浸入式直接固相微萃取与顶空固相微萃取两种方式对不同有机氯农药的富集效率,优化了试验条件.方法线性关系良好,检出限为0.1 ng/L~10 ng/L,定量下限为0.2 ng/L~40 ng/L,RSD<8%,实际水样的加标回收率为67.0%~133%.  相似文献   
903.
杭州市主城区浅层地下水水质现状   总被引:2,自引:1,他引:2  
调查了杭州市主城区浅层地下水水质现状。结果表明,杭州市主城区浅层地下水污染较重,三氮超标现象普遍,而主要污染项目为NH3-N、NO2--N、IMn和总大肠菌群及细菌总数。指出,农业面源污染和生活污水,是造成杭州市主城区浅层地下水氮污染的主要原因。提出分析了地下水水质污染的成因。指出应加强地下水保护以及地下水资源的质量管理。进行科学、合理地开发利用,实现地下水水资源的可持续利用,支持杭州市国民经济的可持续发展。  相似文献   
904.
我国水污染物排放标准评析   总被引:2,自引:0,他引:2  
简述了国家污染物排放标准制定的发展历程及未来规划,对已发布和即将发布的国家水污染物排放标准特点及与国家环境保护标准制修订有关的法律法规、规范性文件进行了分析,提出了在标准实施中加大监督执法、掌控标准实施效果、加强标准基础性研究和健全污染排放标准体系的建议。  相似文献   
905.
气相色谱法同时测定水中28种多氯联苯单体   总被引:3,自引:0,他引:3  
采用液液萃取-浓硫酸磺化净化-气相色谱电子捕获检测器同时测定水中28种多氯联苯单体,必要时利用质谱选择离子监测模式定性,考察了萃取溶剂种类和体积及盐析效应对测定的影响,比较了硫酸磺化和弗罗里硅土柱对萃取液的净化效果。方法在1.00μg/L~47.6μg/L范围内线性良好,当取样体积为200 mL时,方法检出限为0.001μg/L~0.002μg/L,基体加标回收率为95.8%~103%,相对标准偏差≤18.7%。  相似文献   
906.
水功能区划分和水环境功能区划分最终目标都是为了水资源的可持续利用,同时使水环境得到有效的保护.但由于两种划分的立足点不同,划分的侧重点、分类体系、功能区名称存在一定的差异,各自划分容易由于使用和管理的不统一造成混乱.通过浙江省水功能区和水环境功能区的舍二为一划分,合理确定了全省各流域水系水体的水质保护目标和使用功能,以保证水资源开发利用发挥最佳经济、社会、环境效益.  相似文献   
907.
张家口市洋河、桑干河流域水环境健康风险评价   总被引:4,自引:1,他引:4  
张家口市洋河、桑干河流域近几年来水质持续改善,为逐步恢复流域水质和下游官厅水库饮用水备用水源功能提供了条件.文章利用水环境健康风险评价模型,选取了2006年该流域水质监测数据,对流域内10个监测断面由饮水途径引起的水环境健康风险进行了评价.结果表明,该流域水体对人体健康危害最大的是化学致癌物Cr(VI),在各个监测断面中Cr(VI)的个人年风险均超过ICRP推荐的标准.同时,化学致癌物对人体健康危害的个人年风险超过非致癌物的个人年风险;因此对该流域水体的含化学致癌物Cr(VI)和As废水进行控制和治理是降低水环境健康风险的有效途径.  相似文献   
908.
The European Community asks its Member States to provide a comprehensive and coherent overview of their groundwater chemical status. It is stated that simple conceptual models are necessary to allow assessments of the risks of failing to meet quality objectives. In The Netherlands two monitoring networks (one for agriculture and one for nature) are operational, providing results which can be used for an overview. Two regression models, based upon simple conceptual models, link measured nitrate concentrations to data from remote sensing images of land use, national forest inventory, national cattle inventory, fertiliser use statistics, atmospheric N deposition, soil maps and weather monitoring. The models are used to draw a nitrate leaching map and to estimate the size of the area exceeding the EU limit value in the early 1990s. The 95% confidence interval for the fraction nature and agricultural areas where the EU limit value for nitrate (50 mg/l) was exceeded amounted to 0.77–0.85 while the lower 97.5% confidence limit for the fraction agricultural area where the EU limit value was exceeded amounted to 0.94. Although the two conceptual models can be regarded as simple, the use of the models to give an overview was experienced as complex.  相似文献   
909.
Different sources of pollution in Karasu Creek were investigated to obtain the water quality and ratio of contamination in this region. To achieve the main objectives of the present study, water samples were collected from Karasu Creek, starting from flow pattern at the upstream site of Akkaya Dam to the end of the dam, crossing the place where the Creek drains into. Dissolved oxygen, electrical conductivity, temperature and maximum/minimum pH were measured systematically for 12 months in the stations, where the water samples were collected. Chemical analyses of the water samples were carried out by using Cadas 50 S brand UV spectrometer to find out the Pb, Fe, Cu, Zn, Ni, Cr, Cd, S, F and Cn concentrations. These concentration were determined in μg/lt as 80–850; 180–4,920; 10–6,100; 440–25,530; 130–2,400; 120–280; 20–150; 214,250–1,113,580; 1,560–4,270 and 40–690, respectively. To determine metal levels of the water samples, multivariate analyses (element coefficient correlation, coefficient correlation dendrogram, hierarchical cluster analysis dendrogram, model summary and ANOVA) were used. The analyses yielded highly accurate results. There were positive correlations between some elements and their possible sources were the same. The stations which resembled each other along the creek were divided into three groups. The water quality of the creek was low and had toxic qualities. Eutrophication developed in Akkaya Dam along the creek. The source of pollution was thought to be industrial and residential wastes. Absolute (0–100 m), short distance (100–500 m) and medium distance (500–2,000 m) conservation areas should be determined in pollution areas along Karasu Creek and they should be improved.  相似文献   
910.
The productivity of forest sites has been indirectly determined with solo wood production objective in forest management. Forest site productivity should, however, be determined directly in order to implement ecosystem based multipurpose forest management philosophy. This article tackles the problem in distinguishing and mapping forest sites using both direct method and indirect method in Genya Mountain located in central of Artvin State Forest Enterprise. About 112 sample plots were designed and distributed over the area. In each sample plot, soil samples were collected and the classical timber inventory measurements were taken. According to direct method, Soil Moisture Regime (SMR) method is preferred due to a water deficiency in the study area. Water holding capacity was used as an essential criterion for the classification of the forest site. Forest site classifications were assigned regarding the physiographic factors such as landform, aspect, and slope. Five different forest sites classes; dry, moderate fresh, fresh, humid and hygric were determined. According to direct method, the guiding curve was used to generate anamorphic site index (SI) equations and three site index classes; good (SI=I–II), medium (SI=III) and low (SI=IV–V) were determined. Some important differences between the methods were realized. The forest sites determined with site index estimation method indicate that site index I and II is 505.99 ha, III 1095.79 ha and IV and V 992.95 ha, whereas forest sites determined with direct method related to dry site of 937.58 ha, moderate fresh site of 931.90 ha, fresh site of 1,797.71 ha, humid site of 80.48 ha and hygric site of 356.55 ha. The forest site maps of both methods were created using GIS functions. The forest sites of open and degraded areas should be determined according to direct method.  相似文献   
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