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101.
外标法、内标法双结合的分析方法的应用 总被引:1,自引:0,他引:1
随着国家和社会对环境污染的重视,对水质的分析也越来越重要。由于水中杂质含量很少,样品处理过程会带来误差,但对其分析精度的要求却很高,这给分析工作造成一定的困难。文章采用了内标、外标双结合方法对水质中一些特征污染物进行分析。 相似文献
102.
Removal of DDT in drinking water using nanofiltration process 总被引:1,自引:0,他引:1
Weihai Pang 《Desalination》2010,250(2):553-556
The removal of DDT[(1,1-bis(4-chlorophenyl)-2,2,2-trichloroethane)] with synthetic waters was carried out on a nanofiltration (NF) pilot unit. The influence of initial DDT concentration, pH, flux and recovery on the removal of DDT was studied. The presence of humic acid and some inorganic (CaCl2, NaCl, and CaSO4) matters was also tested in the experiment. The removal percent and that of their adsorption on the membrane have been calculated. The results reveal that DDT was easy to be adsorbed on the membranes and the higher the applied pressure the more rapidly saturation of the membrane was achieved. At the initial concentration of 77 μg/L, the equilibrium for DDT adsorption can be achieved in 30 min. With the initial DDT concentration from 5 to 20 μg/L, the removal percent was from 95 to 85%. On condition that recovery was not changed, higher flux can lead to low rejection of DDT. On the other hand, low recovery can have a high rejection when the fluxes were the same. Humic acid can hinder DDT from passing through the membrane by adsorption and inorganic matter (NaCl, CaCl2 and CaSO4) can improve the removal percent by reducing the pore size of the membrane. 相似文献
103.
Korea is experiencing an extraordinarily rapid demographic transition. We investigated the short-term association between air pollution and mortality and assessed the impact of improved air quality on mortality in a rapidly aging city, Seoul, Korea.The generalized additive model (GAM) was used to estimate the relative risks (RR) of mortality associated with changes in air pollution. The time trends, seasonal variations, day of the week effects, and weather effects were controlled in the models. To estimate the health benefits, we used the US Environmental Protection Agency's BenMAP.For people 0–64 years of age, elderly people (65+ years), and all age groups, an increase of 10 μg/m3 in PM10 was associated with increases in daily death counts of 0.27% (95% CI: 0.04–0.50), 0.45% (95% CI: 0.27–0.64), and 0.37% (95% CI: 0.23–0.52), respectively. For ages 0–64 years, elderly people, and all age groups, a 10 ppb increase in 1-hour maximum ozone concentration resulted in an increased risk of daily death counts of 0.28% (95% CI: − 0.19–0.74), 0.96% (95% CI: 0.46–1.47), and 0.81% (95% CI: 0.35–1.26), respectively.For elderly people, it was estimated that the health benefits of attaining the World Health Organization's (WHO) air quality guidelines (AQGs) for PM10 (24-hour average 50 μg/m3) would suggest an annual reduction of 964 (95% CI: 564–1366) premature deaths, and 329 (95% CI: 159–500) premature deaths could be prevented annually in 2015 from attaining the WHO's guidelines for ozone (8-hour average 100 μg/m3).The rapid increase of the elderly population has major consequences and implications for society and public health. This study showed that elderly people are at higher risk for the acute mortality effects of air pollution. Therefore, cleaner air will substantially contribute to improved public health in Seoul, given the growing concern about the adverse effects of air pollution for elderly people. 相似文献
104.
Michael J. Suess 《Indoor air》1992,2(3):180-193
The indoor air quality (IAQ) programme of the World Health Organization Regional office for Europe was initiated in the mid-seventies when it was realized that over 70% of the general population spends its time indoors in homes, office buildings, schools, hospitals, transportation means, etc. The first meting of experts on health aspects related to IAQ was convened in 1979, being probably the first international meeting on IAQ with participation from eastern and western Europe as well as from North America. Seven meetings followed between 1982 and 1990, at which the “sick building” syndrome, IAQ research, formaldehyde and radon, organic pollutants, biological contaminants, combustion products, and mineral fibres were discussed. A ninth meeting on sources, control and mitigation is planned for 1991. 相似文献
105.
The exchange processes between the Rhine river and the alluvial aquifer were analysed in the upper part of the rift valley (upstream of Strasbourg). Hydraulic works, and the consequent suppression of flooding, along the Alsace Rhine floodplain greatly modified these processes. The transfer of persistent toxic micropollutants (organochlorine compounds, mercury), and non-persistent pollutants (organophosphorous compounds: Sandoz spill) from the Rhine to the groundwater-fed streams was exhibited by pollutant bioaccumulation in fish (particularly in the eel) and eutrophication of these streams near the canalized river. Comparison of the hydrological functioning of the two main river floodplains (the Rhine and its tributary, the Ill in the Alsace Rhine plain) shows two completely different exchange processes: in the case of the canalized Rhine, the groundwater is affected by direct transfer of pollutants through the channel bed. In the other case, that of the river Ill, where the floodplain is still widely flooded each year, the self-purification of the floodwaters transferred to the groundwater is very effective: the soil-root system of alluvial forest and meadow apparently having a high purification capacity. 相似文献
106.
A research on the isolation of organic pollutants from water is presented. Five macroporous anionic resins: Varion AT400, Asmit 229N, Zerolite 553N, Wofatite EA60 and Amberlite IR93 were used for humic substances and other anionic organics isolation. Varion AT400 resulted to be the best anionic resin (about 90% recovery of humic substances and a lower recovery for other anionic substances). Nearly complete desorption was achieved by NaCl/NaOH 10%/2% solution, at a volume of about 3.5 times the resin bed volume. 相似文献
107.
N.E. Jiménez Jado C. Fernández Sánchez J.R. Ochoa Gómez 《Journal of Applied Electrochemistry》2004,34(5):551-556
This paper describes the development of electrochemical processes for the oxidative degradation of nitroaromatic compounds, including 2-nitrotoluene, 2-nitroaniline and 4-nitroaniline, in acid wastewaters. The electrolysis process results in the formation of a dark solution in which the concentration of nitroaromatics had been reduced to much lower levels and COD removal efficiencies reached 50%. It was found that the best electrolysis conditions were 96% acid strength, 1000 A m–2 current density and ambient temperature. In addition, electrochemical degradations were always more effective when substituents are in the para-position and lead to significant electrophilic character. A black powdery product was isolated from the dark solution; this resulted from the anodic oxidation of amines initially produced at the cathode. The black product was further destroyed by anodic oxidation during prolonged electrolysis. 相似文献
108.
"十二五"以来,我国煤电大气污染物的控制取得了很大的成就,烟尘、二氧化硫、氮氧化物排放总量和强度快速下降,控制水平达到世界先进水平。"十三五"乃至更长时期,煤电仍将承担国家大气污染物减排的重任。重点研发高性能、高可靠性、高适用性、高经济性污染物的控制技术、资源化技术、多污染物协同控制技术是未来我国煤电大气污染物控制的主要技术方向。预计到2020年,烟尘、二氧化硫、氮氧化物年排放量分别降至2×10~5~3×10~5 t、1×10~6~1.5×10~6 t、1×10~6~1.5×10~6 t。 相似文献
109.
110.
简述了欧美国家特别是我国为控制发动机污染物排放所采取的措施,并制定了一些法规和标准;较为详尽地介绍了中美合资生产的康明斯发动机的排放性能及所达到的排放限制要求,从而凸显其绿色环保的优越性。 相似文献