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11.
TOMIOKA Kenichi OGUMA Koichi SEKITatsuya 《环境化学》2003,22(3):211-214
1 IntroductionLeadiswellknownasoneofthemosttoxicmetalsandnotedinthefieldofenvironmentalchemistry[1 ] .Theleadconcentrationinnaturalwaterisextremelylow (sub μg·l-1 level)sothatsomepreconcentrationstepmustbeincludedtoassurethesensitivityofaconventionalin… 相似文献
12.
An atmospheric dispersion model was developed for the environmental impact assessment of thermal power plants in Japan, and a method for evaluating topographical effects using this model was proposed. The atmospheric dispersion model consists of an airflow model with a turbulence closure model based on the algebraic Reynolds stress model and a Lagrangian particle dispersion model (LPDM). The evaluation of the maximum concentration of air pollutants such as SO2, NOx, and suspended particulate matter is usually considered of primary importance for environmental impact assessment. Three indices were therefore estimated by the atmospheric dispersion model: the ratios (alpha and beta, respectively) of the maximum concentration and the distance of the point of the maximum concentration from the source over topography to the respective values over a flat plane, and the relative concentration distribution [gamma(x)] along the ground surface projection of the plume axis normalized by the maximum concentration over a flat plane. The atmospheric dispersion model was applied to the topography around a power plant with a maximum elevation of more than 1,000 m. The values of alpha and beta evaluated by the atmospheric dispersion model varied between 1 and 3 and between 1 and 0.4, respectively, depending on the topographical features. These results and the calculated distributions of y(x) were highly similar to the results of the wind tunnel experiment. Therefore, when the slope of a hill or mountain is similar to the topography considered in this study, it is possible to evaluate topographical effects on exhaust gas dispersion with reasonable accuracy using the atmospheric dispersion model as well as wind tunnel experiments. 相似文献
13.
Levels of PCDDs, PCDFs and Co-PCBs in human milk in Saitama, Japan, and epidemiological research 总被引:5,自引:0,他引:5
From 1998 to 2000, the dioxin levels were measured in the milk of 299 mothers who lived in Saitama prefecture, Japan. Factors that influenced the dioxin levels were investigated based on a questionnaire given to the milk donors at that time. It was found that the dioxin levels in the milk of the mothers who smoked were lower than those of non-smokers, and the dioxin levels were generally low in the mothers who were heavy smokers. The average dioxin levels in the milk of mothers who had been breast-fed were higher than those given formula, and there was a significant difference in the dioxin congeners. It was also found that the dioxin levels in milk of the women who regularly consumed fish and shellfish were generally higher. There was a strong correlation between summation operator TEQ and PCB126. The data suggested that PCB126 could be a useful indicator for the simplified analysis of dioxin in human milk. 相似文献
14.
The octanol/water partition coefficients (P ow) of six monoisocyanate and five diisocyanate compounds were determined by high performance liquid chromatograph (HPLC) methods. Two HPLC peaks, a broad tailed peak followed by a sharp one, were observed with all compounds. The later peak was identified as the isocyanate compound. The P ow value for each isocyanate compound was determined by fitting the capacity factor of the peak to the regression equation drawn from those of reference compounds. The hydrophobic substituent constants for the isocyanate group were calculated with each of the compounds. The value of this constant was strongly dependent on the type of carbon bound to the isocyanate group and the average values for the aromatic and aliphatic isocyanate groups were 0.35 and — 0.52, respectively. Because of the reactivity of those compounds in the aquatic environment, the P ow has little relevance to calculation of their environmental fate and ecotoxicity. 相似文献
15.
Saito K Takekuma M Ogawa M Kobayashi S Sugawara Y Ishizuka M Nakazawa H Matsuki Y 《Chemosphere》2003,53(2):137-142
A simple and rapid method for the extraction and cleanup of dioxins from house dust was developed using an accelerated solvent extraction (ASE) method and a multi-layer silica-gel cartridge. It was found that the WHO-TEQ levels of dioxins extracted from the house dust obtained by both a conventional soxhlet extraction and the ASE were almost equal, when the data obtained by both methods were compared. As for the cleanup method, a multi-layer silica-gel cartridge yielded higher dioxin recoveries than the alkaline digestion method. The average values of the dioxins in house dust from Kumagaya city and Sendai city in Japan (Sendai city is bigger than Kumagaya city with respect to the population and industry), were 15.6 pg TEQ/g (8.6-26.0 pg TEQ/g, n=5, Kumagaya city) and 16.0 pg TEQ/g (5.9-30.5 pg TEQ/g, n=5, Sendai city), respectively. 相似文献
16.
Narukawa T Riley KW French DH Takatsu A Chiba K 《Journal of environmental monitoring : JEM》2003,5(5):831-836
A basic investigation of boron in discharged fly ash by coal fuel thermal power plants in several worldwide locations was carried out. Eight kinds of fly ash sample were prepared from eight coal fuel thermal power plants. Two of the fly ash samples were used to examine the relationship between the concentration of boron in fly ash and the particle size. When the particle size of fly ash is smaller, there is a possibility that it will be released into the air and spread over a wide area in the environment. However, it has become apparent that fly ash of smaller particle size has a higher concentration of boron and a higher enrichment factor. In other fly ash samples, the boron contents were examined and leaching tests were carried out. There is acidic fly ash as well as alkaline fly ash that contains larger amounts of acidic or basic salts. On alkaline fly ash, when the concentration of boron bound to Fe-Mn oxide is low; it has become apparent that leaching boron is increased in a solution with lower pH of approximately 4 which is nearly the pH of acid rain. 相似文献
17.
Measurements of aerosol size-separated number concentrations were performed in March 2001 on the Tama Hills of Japan, located
near regions of heavy industry. The concentrations of particles larger than 1.0 μ m in diameter dramatically increased during
the Kosa phenomena on 6–8 and 18–24 March. The number concentrations of coarse particles (> 3.0 μm) showed distinct diurnal
variations, especially during the Kosa events. Fine particles smaller than 0.5 μm increased when the relative humidity was
high and the wind speed was low. On the other hand, the coarse particles concentrations were well correlated with wind speed
and temperature. The dry deposition velocity of the coarse particles at the forest canopy was estimated from the nighttime
decrease in the number concentrations. 相似文献
18.
A method for regional-scale material flow and decoupling analysis: A demonstration case study of Aichi prefecture, Japan 总被引:6,自引:0,他引:6
Junzo Tachibana Keiko Hirota Naohiro Goto Koichi Fujie 《Resources, Conservation and Recycling》2008,52(12):1382-1390
We have developed a method to analyse the annual material flow in a prefecture and have calculated environmental indicators for a prefecture. Material flow analysis (MFA) is important to clarify the structure of a regional society and obtain environmental indicators for a circular society. However, MFA has not advanced in local governments because of few local statistics. We have developed a method to analyse the annual material flow in Aichi prefecture from 1980 to 2000 using an input–output (I–O) table and statistics of Aichi. We have verified the accuracy of this method by comparing its results for 2000 which calculated on the basis of official I–O table for 1995 with the I–O table data for 2000; the correlation coefficient obtained in this case is greater than 0.95. Moreover, by performing MFA, we have estimated the resource consumption and decoupling indicator of each industry in Aichi prefecture from 1980 to 2000. We could obtain more detailed and accurate environmental indicators by using our method. From these results, we could estimate the progress of Aichi prefecture towards a circular society. 相似文献
19.
Mercury (Hg), cadmium (Cd), iron (Fe) manganese (Mn), zinc (Zn) and copper (Cu) concentrations in the liver, kidney and muscle of nine killer whales (including three calves) that stranded together in the northern area of Japan were determined. The Hg and Cd concentrations were found at trace levels in the calf organs, and increased with age. The Fe concentration in the muscle was significantly lower in the calves than in the mature whales and also increased with age. In contrast, Mn and Cu concentrations in the muscle were significantly higher in the calves than in the mature whales, and changes in the Zn concentration relative to age were unclear. These results suggest minimal mother-to-calf transfer of the toxic metals Hg and Cd and accumulation of these metals in the organs with age, while the essential metals Mn and Cu were found at higher concentrations in the muscle of calves than in mature whales. 相似文献
20.
Yamaura Koichi Sakaue Shin Washida Toyoaki 《Environmental Economics and Policy Studies》2017,19(2):405-426
Environmental Economics and Policy Studies - Genetic resources have been widely used for agricultural animal breeding, drug development, and biomaterials. Coherent assessments of global warming on... 相似文献