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121.
粗苯污染事故应急处理   总被引:3,自引:0,他引:3  
针对一次苯泄漏事故的应急处理过程、方法进行论述与总结,并分析了事故现场周围地表、地下水中苯污染浓度的变化情况,提出了该类事故的应急措施,以此作为处理同类事故的参考和依据。  相似文献   
122.
A sediment sampling based on a two-dimensional mapping was performed in the harbour of Trieste (northern Adriatic Sea), considering 28 sites exposed to pollutant inputs from harbour and industrial activities. Polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) were determined in surface sediments, because these very persistent pollutants seem to be responsible for the depletion of benthic populations observed in this area. The correlation matrix indicates that PAHs and PCBs are non-correlated, and probably have different sources. Both cluster analysis performed on the sampling sites and graphical drawing of the PAH sediment contents make it possible to locate along the shoreline a band of more polluted sediments, clustered around a site facing a steelmaking factory, to be considered as the main source point for PAHs. The evaluation of phenanthrene to anthracene (P/AN) and fluoranthene to pyrene (FL/PY) ratios permits the assessment of the pyrolytic, industrial origin of these PAHs, rejecting a second possible source of hydrocarbons (i.e., an oil-pipeline terminal, situated near the steelmaking factory). Graphical drawing of the total PCB iso-concentrations reveals a different source-point for this other category of very persistent pollutants.  相似文献   
123.
The composition of precipitation is being monitored in collectors sited throughout the United Kingdom. In the first year, 1986, hydrogen ion, nitrate, ammonium and non-marine sulphate were measured in samples from 47 sites and annual mean concentrations determined. Spatial analysis based on Regionalized Variable Theory revealed autocorrelation in all four ions and reasonable bounded models were fitted to the sample variogram of all four. These were then used to estimate values of a fine mesh grid by simple kriging, and the estimates were then contoured. The estimation errors were similarly mapped, and both sets of maps are presented. The maps show that concentrations of these ions are greatest in eastern parts of the country, as expected from consideration of European emissions and weather patterns. For the first time estimation errors were also mapped and show how the network could be improved.  相似文献   
124.
Eggs were collected from seven seabird species at colonies on the British Columbia coast from 1983 to 1986 and analyzed for organochlorine contaminants. Total PCB levels (wet weight) were highest in double-crested cormorants (Phalacrocorax auritus) from the Fraser estuary (2.91 mg kg-1) and the Strait of Georgia (3.79 mg kg-1). Highest DDE levels were in fork-tailed storm-petrels (Oceanodroma furcata) from the Queen Charlotte Islands (1.68 mg kg-1). Organochlorine levels were generally lower in eggs from the mid 1980s than in those collected in the early 1970s. Organochlorine levels in Pacific alcids and hydrobatids foraging in offshore locations were compared to those in the same or ecologically similar species from the Canadian Atlantic coast. DDT- and HCH-related compounds were higher in Pacific populations while levels of dieldrin, oxychlordane, and HCB were generally lower. With the exception of -HCH, levels of all measured organochlorines were lower in cormorants breeding in the Fraser River estuary than in cormorants from the St. Lawrence River estuary on the Atlantic coast.  相似文献   
125.
A second derivative spectrometer custom fitted with a 1 m stainless steel White cell and maintained at 105°C is used to make real-time measurements of volatilized NH3 from urea-amended soil. Comparison of the technique to impinger data shows a 5–16% discrepancy between the two techniques; however, other experiments presented suggests that this is not real. Sulfur dioxide and nitrous oxide interferences are discussed, though they were not found to be present in this study. Instrument response time is shown to be fast if 67% of the total response is achieved in less than 5 min. Fast response is achieved for ammonia if wall-adsorption effects are minimal and if ammonia mass flow is maintained at 0.2 μg min-1.  相似文献   
126.
The impact of point (domestic and industrial effluents) and non-point (agricultural land runoff) pollution sources on the quality of the receiving waters of the Evrotas River (Laconia, Greece) was investigated during a monitoring study from August 1991 to August 1992. The part of the river which was located near the city of Sparta was seasonally influenced by the discharge of effluents from orange juice plants (operating during winter) and by the discharge of septage for the emptying of cesspools which are serving part of the city. The low dilution of incoming pollutants (septage) during the low water flow in summer lead to the decreasing self-purification capacity of the river and the development of septicity conditions in some of its parts. In the vicinity of intensively cultivated areas, the high concentrations of nitrogen and phosphorus which were detected in the river water during winter and spring may be partly attributed to the leaching of the applied fertilizers because of nirogen mobilization and soil erosion, following the season's precipitations. The protection of the Evrotas River water Quality must therefore include adequate treatment of the septage produced in the area, as well as the construction of wastewater treatment plants for the major industries of the area. The non-point pollution could be controlled by the restoration of the Evrotas riparian vegetation, together with a more rational use of fertilizers in the area.  相似文献   
127.
A method is described whereby dielectrophoresis of algal cells is used to perform rapid water quality analysis, specifically detecting the presence of CuSO4. The dielectric collection spectrum of the fresh water alga Selenastrum capricornutum was determined for a range of concentrations of CuSO4 from 25 mg L(-1) to 0.25 mg L(-1) for exposure times of 15 min and 18 h. In all cases increasing the concentration of CuSO4 reduced cell collection, but a step reduction was observed in collection between 2 mg L(-1) and 5 mg L(-1). This method has potential for forming a rapid, low-cost test for water quality with broad specificity and significantly reduced analysis time compared to current methods.  相似文献   
128.
Prices for ferro-alloys have hardened due to the closure of plants in developed countries on account of increasingly stringent pollution control legislation, resulting in a higher cost of production. A ferro-alloy industry with a capacity of 80000 MT per annum was selected to study the nature of pollution. Because of the objectionable nature of polluting air in and around the plant it was located in a rural area where there was no other industry. The area was agriculturally active and there was no effective control system for this plant.The quality of ambient air around the plant site is discussed in this paper along with the meteorological conditions. The maximum concentration of suspended particulate matter (SPM) was 768 µg/NM3 downwind of the plant, minimum 184 µg/NM3, and the average was more than 446 µg/NM3. The presence of heavy metals, viz. Fe, Mn, Cr and Pb, was also assessed. The concentration of Fe was 50 µg/NM3 downwind and 10 µg/NM3 upwind. The concentration of other metals followed a similar trend.  相似文献   
129.
Patchy distributions: Optimising sample size   总被引:1,自引:0,他引:1  
A method for estimating sample size which does not require an a priori definition of desired precision, or the assumption that the population is normally distributed with constant variance, has recently been proposed. This paper discusses this method and presents five modifications which make the method easier to use and reduce the probability of estimating a larger sample size than is actually required. The method is extended and used to estimate the mean abundance of patchily distributed benthic organisms. The technique can be used to guide the design of any environmental sampling programme, be it physical, chemical or biological, where comparisons between times and/or locations are required. Trade-offs between numbers of replicates and numbers of levels/sites are discussed.  相似文献   
130.
The behaviour of the three organophosphate esters tributyl phosphate (TBP), tris(2-chloroethyl)phosphate (TCEP) and tris(2-butoxyethyl)phosphate (TBEP) during infiltration of river water to ground water has been investigated. The monitoring site is the Oder River and the adjacent Oderbruch aquifer. From March 2000 to July 2001, 76 ground water samples from monitoring wells located close to the Oder River and nine river water samples were collected. Additionally, influent and effluent samples from local waste water treatment plants, one sample of rain water and samples of roof runoff were collected. All samples were analysed by solid-phase-extraction followed by gas chromatography/mass spectrometry. TBP, TCEP and TBEP were detected at mean values of 622 ng l(-1), 352 ng l(-1), and 2955 ng l(-1), respectively in municipal waste water effluents. This points to a major input of these compounds into the Oder River by municipal waste water discharge. The concentrations of TBP and TBEP decreased downstream the Oder River possibly due to aerobic degradation. TBP, TCEP and TBEP were detected in ground water influenced predominantly by bank-filtered water. This demonstrates a transport of organic compounds by river water infiltration to ground water. TBP, TCEP and TBEP were also detected in rain water precipitation, roof runoff and ground water predominantly influenced by rain water infiltration. This hints to an input of these compounds to ground water by dry and wet deposition after atmospheric transport. Organophosphate esters were also detected in parts of the aquifer at 21 m depth. This demonstrates low anaerobic degradation rates of TBP, TCEP and TBEP.  相似文献   
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