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71.
Abstract The characteristics of fine particulate pollution (PM10 and PM2.5) were measured at urban and suburban sites in Jinan during the 2008–2009 heating and non-heating seasons. The results showed that PM10 and PM2.5 pollution was quite serious, and PM mass concentration was higher during the heating season than the non-heating season. PM was the highest in the chemical factory and lowest in the development zone. The mass concentrations of PM10 and PM2.5 were linearly related, and the mass concentration ratio of PM2.5/PM10 was up to 0.59 in urban areas. PM pollution in Jinan was related to local meteorological factors: PM2.5 mass concentration and humidity were positively correlated, and PM2.5 mass concentration was negatively correlated with both click on the temperature and wind speed, although wind speed varied more. 相似文献
72.
太湖夏季水体中尿素的来源探析 总被引:4,自引:2,他引:4
为研究尿素氮在太湖生态系统中的作用,于夏季采集湖体及环湖河道水样进行尿素及不同形态氮素含量分析.通过河道及湖体的82个调查点位生态指标的同步分析,得出以下结果:①太湖尿素氮含量变化范围为0.011~0.161 mg·L-1,总体呈现出西北高,东南低的变化趋势,与流域主要污染源分布有关;②太湖水体溶解性氮以无机氮库为主,铵硝比为5∶1,其中尿素氮占总氮、溶解性总氮、溶解性有机氮和生物可利用氮的平均质量分数分别为2.28%、5.91%、15.86%、6.22%,生态作用不容忽视;③环湖河道的尿素氮含量比湖体高出一倍,出湖河道尿素氮含量还略高于入湖河道;④太湖尿素氮与其他形式氮之间可能存在彼此转换关系,尿素氮含量与高锰酸盐指数、不同形态氮含量均呈显著正相关关系,与溶解氧呈显著负相关关系;湖体的尿素氮含量与叶绿素a含量呈弱正相关,与底栖生物、浮游动物种群的空间分布有密切联系.本研究表明太湖水体中尿素氮可能是湖体有机、无机态氮转化的桥梁,是湖体自身氮素循环快慢的标志,氮的循环速率控制尿素氮含量,高氮(特别是有机态氮)含量及低溶解氧条件是尿素升高的前提.太湖湖体尿素含量受外源输入和内源转化的双重影响. 相似文献
73.
Bernhard Kienzler Berthold Luckscheiter Stefan Wilhelm 《Waste management (New York, N.Y.)》2001,21(8):741-752
Results of leaching experiments using active and inactively simulated HLW glass in concentrated NaCl solution are described. Measured solution concentrations of glass components, fission products and actinides are compared with computed data. The computed pH value corresponds with the findings from experiments with inactively simulated glass samples. Moreover, the concentrations of silica and strontium can be described adequately by reaction path modelling. The computed U concentration is explained by the precipitation of schoepite or Na2U2O7. The computed Am concentration significantly exceeds the measured data. This may be attributed to sorption processes on corrosion products of the glass, which are relevant also for lanthanide elements under the conditions of the experiments. This hypothesis is tested by solid solution approaches and by computing sorption of Am onto SiO2 precipitates. 相似文献
74.
Britta Grote Wilhelm Hagen Marek R. Lipinski Hans M. Verheye Erling K. Stenevik Werner Ekau 《Marine Biology》2011,158(5):1005-1017
Cape hakes, Merluccius paradoxus and M. capensis, are important gadoid fish that are commercially harvested in the Benguela Current system off Namibia and South Africa. The
aim of this study was to elucidate the nutritional condition and feeding preferences of their larvae. Hake eggs and larvae
were sampled in austral spring of two consecutive years, 2007 and 2008, off the west coast of South Africa. They were identified
to species using genetics, and total lipid content and fatty acid (FA) composition were analysed for each individual egg and
larva to compare the condition of different early life stages of both hake species. Higher abundances of M. paradoxus eggs and larvae were consistently found compared to M. capensis. In both species, eggs contained wax esters (WE) and had significantly higher lipid content per dry mass than larvae. Lipid
content as well as FA composition changed with the developmental stage of larvae. Quantities of essential fatty acid (EFA)
increased with feeding of larvae due to dietary lipid incorporation. In 2007, yolk-sac larvae contained significantly lower
total lipids than in 2008. It is argued that this was due to reduced lipid transfer by the spawning females to the eggs. These
findings indicate that maternal effects are important in determining condition of hake larvae and that this may have an effect
on their survival and subsequent recruitment. 相似文献
75.
Polybrominated diphenyl ether in sewage sludge in Germany 总被引:2,自引:0,他引:2
Sewage sludge samples from 11 municipal waste water treatment plants in Germany were collected from March 2002 to June 2003. Total Tri- to HpBDE concentrations (sum of significant congeners BDE 28, 47, 99, 153, 154 and 183) ranged from 12.5 to 288 (median 108) and DeBDE (BDE 209) concentrations from 97.1 to 2217 (median 256) ng/gd.m. BDE 209 dominated the congener profile. A significant change of the Tri- to HpBDE congener profile (% of total BDE 28, 47, 99, 153, 154, 183 without 209) in sludge from different stages of the waste water treatment process (primary sludge, secondary excess sludge and (dewatered) digested sludge), indicating a degradation of DeBDE to these congeners, was not observed. 相似文献
76.
Endocrine disruptors in freshwater streams of Hesse, Germany: changes in concentration levels in the time span from 2003 to 2005 总被引:3,自引:1,他引:3
Four small freshwater streams in the region known as Hessisches Ried in Germany were investigated with respect to the temporal and spatial concentration variations of the endocrine disruptors bisphenol A (BPA), 4-tert-octylphenol (4-tert-OP), and the technical isomer mixture of 4-nonylphenol (tech.-4-NP). Measured concentrations of the target compounds in the river water samples ranged from <20 ng/l to 1927 ng/l, <10 ng/l to 770 ng/l, and <10 ng/l to 420 ng/l for BPA, 4-tert-OP and tech.-4-NP, respectively. BPA levels were, with the exception of two samples, below the predicted no-effect concentration (PNEC) for water organisms. Tech.-4-NP concentrations showed a significant tendency of decreasing concentrations during the sampling period. This is mainly attributed to the implementation of the European Directive 2003/53/EG, which restricts both the marketing and use of nonylphenols. Results from the analysis of additionally collected water samples from sewage treatment plant (STP) effluents indicate that the STPs cannot be the only sources for tech.-4-NP found in the river water. 相似文献
77.
Wilhelm Hoeflinger 《中国人口.资源与环境(英文版)》2010,8(4)
The characteristics of fine particulate pollution(PM10and PM25)were measured at urban and suburban sites in Jinan during the 2008-2009 heating and non-heating seasons.The results showed that PM10 and PM2.5 pollution was quite serious,and PM mass concentration was higher during the heating season than the non-heating season.PM was the highest in the chemical factory and lowest in the development zone.The mass concentrations of PM10 and PM2.5 were linearly related,and the mass concentration ratio of PM2.5/PM10 was up to 0.59 in urban areas.PM pollution in Jinan was related to local meteorological factors: PM2.5 mass concentration and humidity were positively correlated,and PM2.5mass concentration was negatively correlated with both click on the temperature and wind speed,although wind speed varied more. 相似文献
78.
Wilhelm Ludwig 《Die Naturwissenschaften》1937,25(28):459-460
79.
80.