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61.
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The geographical and temporal distribution patterns of airborne dust particulates have been studied in different representative areas of Raipur City. Dust fall samples from different sites were collected and some selected toxic metals namely Cr, Mn, Fe, Ni, Cu, Zn, Sb and Pb in them were determined by AAS. Total annual flux of 11.7, 541.4, 2751.0, 14.2, 9.8, 90.9, 17.6, and 17.7 kg km(-2) y(-1) were measured for Cr, Mn, Fe, Ni, Cu, Zn, Sb, and Pb respectively. The occurrence of metal concentration were generally in the order industrial > heavy traffic > commercial > residential area in Raipur city. The results of analysis show the existence of toxic metal concentration in the order Fe > Mn > Zn > Pb approximately Sb > Ni > Cr > Cu in Raipur city. These large levels of metal pollutants have also been correlated with some meteorological parameters like temperature, relative humidity and wind velocity, and strong positive correlations have been observed.  相似文献   
63.
Four automatic weather stations (AWS) were installed on the slopes and foot areas of the Tianshan and Kunlun Mountains along a longitude of 80 degrees east: (1) Taglak 2400 m a.s.l., (2) Aksu 1000 m, (3) Kartash 2800 m, and (4) Qira 1700 m. These two slopes face the Taklimakan Desert. Tagliak lies on the southern slope of Tianshan, and Kartash on the northern slope of Kunlun. The meteorological characteristics of the mountainous regions were investigated using surface data obtained during an intensive observation period (IOP) in spring 2002. It was found that visibility on the slopes decreases in the daytime, and there is no relationship between visibility and wind speed in the mountainous areas. Two snow layers containing dust particles were observed in the snow cover in Taglak during the IOP in spring 2003. These results suggest that a warm air parcel containing aeolian dust climbs over the slopes of the mountainous areas, and dust particles in the mountainous areas are transported from the foot areas.  相似文献   
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This study emphasizes nutrient balance of soils in the farmland application of composted biosolid wastes. The loading rates of plant nutrients following the compost application to farmland in Japan were estimated and compared with the nutrient uptake of agricultural plants. Results show that the current compost application in Japan can meet the requirements of agricultural plants for plant nutrient Ca, except for K, Mg, P, Fe, Mn, Cu, and Zn. The compost application could realize the safe disposal of biosolid wastes and the effective recycling of plant nutrients in composts to soils without causing heavy metal accumulation. The application manner of composts affects the heavy metal accumulation in farmlands. Field examination indicates that the excessive compost application has led to the heavy metal accumulation in compost-amended farmlands. Measuring the nutrient balance in compost-amended farmlands is well suitable for explaining the accumulation of heavy metals, such as Cu and Zn.  相似文献   
66.
Nakao T  Aozasa O  Ohta S  Miyata H 《Chemosphere》2002,48(8):885-896
Dioxins including polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and co-planar polychlorinated biphenyls (Co-PCBs) are highly toxic. Even at environmental pollution levels, they cause hormonal damage in women, and they have been shown to induce immunosuppression and genital function damage in humans. In this study, a new method using isotope dilution was established to detect PCDDs, PCDFs and Co-PCBs in human hair. This method, comprised of washing and cutting of hair, alkaline decomposition, hexane extraction, multilayer silica gel column chromatography, high performance liquid chromatography with a porous graphite carbon column and analysis by high resolution gas chromatography/high resolution mass spectrometry, enabled us to analyze PCDDs, PCDFs and Co-PCBs at trace levels of less than pg/g with good reproducibility. In addition, there was a correlation between some isomers in human hair and blood collected from identical donors. Human hair analysis is useful to evaluate human risk assessment including that due to environmental pollution.  相似文献   
67.
I. Imai  K. Itoh 《Marine Biology》1987,94(2):287-292
Effects of storage temperature on the dormancy and maturation of dormant cells of Chattonella spp. were investigated by the extinction dilution method using sediment samples collected in 1984 after the blooming in Harima-Nada. Seasonality of germinability in fresh sediments was also studied in 1985. A storage period of more than 4 months with a low temperature (11°C) was essential for the maturation to induce the germination capacity of dormant cells. The optimal temperature for germination (22°C) had no effects on the maturation. Using fresh Suo-Nada sediments, a marked seasonality of germinability was confirmed. It was weak from autumn to early winter, then strengthened gradually up to a high level, which was maintained between spring and early summer, and again decreased rapidly during summer. The annual life cycle of Chattonella spp., including vetetative and dormant phases, was summarized as follows: (1) vegetative cells in early summer originate from germination of dormant cells in sediments; (2) they form overwintering dormant cells during the summer season; (3) dormant cells spend a period of spontaneous dormancy until next spring; (4) the duration of post dormancy, an enforced one due to low temperatures, follows until early summer. The life cycle of Chattonella spp. is therefore well adapted to the temperature regime in temperate seas such as the Seto Inland Sea of Japan.  相似文献   
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In order to develop effective conservation strategies for endangered migratory species, the link between feeding and breeding grounds needs to be clarified. In this study, the genetic compositions of consecutive Japanese feeding aggregations of green turtles (Chelonia mydas) along the Kuroshio Current were examined by mixed-stock analyses of mitochondrial DNA control-region sequences. The results indicated that the southern feeding aggregation around Yaeyama (24.3°N, 124.0°E) was sourced from various Pacific rookeries in the Yaeyama, Ogasawara, Western Pacific, and Indian Oceans and Southeast Asia. Among northern feeding aggregations, the Ginoza (26.5°N, 128.0°E) aggregation was also sourced from the Western Pacific Ocean, but the Nomaike (31.4°N, 130.1°E), Muroto (33.2°N, 134.2°E), and Kanto (35.6°N, 140.5°E) aggregations were contributed mostly by the closer Ogasawara rookeries. The reduced contribution from tropical Pacific rookeries to northern feeding aggregations and the significant correlation between genetic differentiation and geographical distance matrices of feeding aggregations indicated that most hatchlings from these regions transported by the Kuroshio Current settle in upstream feeding grounds along the Japanese archipelago, implying that current flow influences the composition of feeding aggregations. Differences in the composition of relatively close neritic feeding aggregations have important conservation implications, for which both regional and multinational conservation strategies are needed.  相似文献   
70.
To achieve both high-efficiency power generation and high detoxification performance, advanced-type waste power generation plants such as pyrolysis and gas reforming plants are suggested. Further surveys on actual operational data of these plants are required in terms of reliability of the system when it is introduced to waste disposal sites. To verify the technical effectiveness of advanced-type waste power generation using the pyrolysis and gas reforming method, we evaluated 10?tons/day of municipal solid wastes (MSW) treated in a demonstration plant. A demonstration test was conducted over 100?days including 35?consecutive days of operation treating MSWs. The test results show high recycling performance and harmless nature of the plant which proves it to be an excellent waste recycling system. Major test results are as follows: (1) stabilization of waste treatment is possible with the wastes of various qualities, (2) clean gas is produced from the waste whose energy recovery ratio is approximately 40?%. (3) 99.3?% weight % of dried waste are recovered as valuable materials such as clean gas, char and metal, (4) total amount of dioxin emission to the outside of the plant is very small, down to 0.0051–0.018?μg?TEQ per ton waste.  相似文献   
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