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801.
The removal of solubilized vat dye effluent using photo detoxification method was studied at various pH ranges. Experiments
were carried out with synthetic effluent using total dye concentrations of 50, 100, 200, 300, and 350 mg/L. In sunlight photo
oxidation, the original soluble vat dye is precipitated and can be filtered and reused by the textile industries. The effect
of the different concentrations (1,000, 2,000, 3,000 mg/L) of total dissolved solids on the removal of vat dye was also carried
out in the photo detoxification process. The efficiency of the dye removal was found to be 99 %. 相似文献
802.
Fluoride concentration of groundwater reserves occurs in many places in the world. A critical area for such contamination
in India is alluvial soil of the plain region, consisting of five blocks (Jhajjar, Bahadurgarh, Beri, Matanhail, and Sahalawas)
of the Jhajjar District adjacent to the National Capital Territory of India, New Delhi. The purpose of this study was to assess
the association between water fluoride levels and prevalence of dental fluorosis among school children of the Jhajjar District
of Haryana, India. The fluoride content in underground drinking water sources was found to vary in villages. Hence, the villages
were categorized as high-fluoride villages (1.52–4.0 mg F/l) and low/normal-fluoride villages (0.30–1.0 mg F/l). The source
of dental fluorosis data was school-going children (7–15 years) showing different stages and types of fluorosis who were permanent
resident of these villages. The fraction of dental fluorosis-affected children varied from 30% to 94.85% in the high-fluoride
villages and from 8.80% to 28.20% in the low/normal-fluoride villages. The results of the present study revealed that there
existed a significant positive correlation between fluoride concentration in drinking water and dental fluorosis in high-fluoride
villages (r = 0.508; p < 0.001) and insignificant correlation in low-fluoride villages. 相似文献
803.
Environmental fate and bioavailability of wood preservatives in freshwater sediments near an old sawmill site. 总被引:1,自引:0,他引:1
Impacts of an old contaminated sawmill site located in Eastern Finland were studied, with emphasis on transportation and bioaccumulation of wood preservatives in the surrounding water system. To assess the transportation of chlorophenols and chromated copper arsenate (CCA) from the sawmill to the nearby lake, the concentrations of these compounds in selected sediment samples were analyzed. To assess the contribution of a pulp mill further upstream, the concentration of extractable organic halogens (EOX) was analyzed. Bioaccumulation of wood preservatives from sediments was examined using Lumbriculus variegatus as test organism. In sediments collected from the sawmill area, concentrations of chlorophenols, arsenic, chromium and copper were high. In the surrounding area the concentrations of these compounds were slightly elevated at some sampling points but were mostly within the natural range of variation. Thus, it can be concluded that transportation of wood preservatives from the sawmill area to its surroundings is fairly low. However, 60 microg/l of arsenic and 50 microg/l of copper were found in water taken from a brook that runs through a landfill area of the sawmill to the nearby river, and the concentration of arsenic in the surface sediment at one sampling point in the lake was slightly elevated. The total amount of organohalogens in sediment was higher in the river and the lake than in the sawmill area. Of all the wood preservatives studied, only arsenic was found to bioaccumulate in present conditions, reaching a tissue concentration of 362 microg/g dw in organisms exposed for 28 days to sediment from the brook. High concentration of arsenic in oligochaeta tissue was related to high concentration of arsenic in the pore water. 相似文献
804.
The enhanced generation of singlet oxygen (1O2) during oxidation of farmorubicin in the Co(II) + H2O2 system was studied using chemiluminescent, fluorescent and spectrophotometic techniques. The influence of 1O2-quenchers, catalase, superoxide anion radical (O2*-) and hydroxyl radical (HO*) scavengers on the light emission was studied. The spectrophotometric determination of 1O2 was based on bleaching of p-nitrosodimethylaniline caused by an intermediate product of the reaction of 1O2 with imidazole, and was followed by monitoring the decrease in optical density at 440 nm. 相似文献
805.
806.
807.
H Vandenhove Y Thiry A Gommers F Goor J M Jossart E Holm T G?fvert J Roed A Grebenkov S Timofeyev T G?ufert 《Journal of environmental radioactivity》2001,56(1-2):157-184
When dealing with large-scale environmental contamination, as following the Chernobyl accident, changed land use such that the products of the land are radiologically acceptable and sustain an economic return from the land is a potentially sustainable remediation option. In this paper, willow short rotation coppice (SRC) is evaluated on radiological, technical and economic grounds for W. European and Belarus site conditions. Radiocaesium uptake was studied in a newly established and existing SRC. Only for light-texture soils with low soil potassium should cultivation be restricted to soils with contamination levels below 100-370 kBq m-2 given the TFs on these soils (5 x 10(-4) and 2 x 10(-3) m2 kg-1) and considering the Belarus exemption limit for firewood (740 Bq kg-1). In the case of high wood contamination levels (> 1000 Bq kg-1), power plant personnel working in the vicinity of ash conveyers should be subjected to radiation protection measures. For appropriate soil conditions, potential SRC yields are high. In Belarus, most soils are sandy with a low water retention, for which yield estimates are too low to make production profitable without irrigation. The economic viability should be thoroughly calculated for the prevailing conditions. In W. Europe, SRC production or conversion is not profitable without price incentives. For Belarus, the profitability of SRC on the production side largely depends on crop yield and price of the delivered bio-fuel. Large-scale heat conversion systems seem the most profitable and revenue may be considerable. Electricity routes are usually unprofitable. It could be concluded that energy production from SRC is potentially a radiologically and economically sustainable land use option for contaminated agricultural land. 相似文献
808.
Sahu MK Poorani E Sivakumar K Thangaradjou T Kannan L 《Journal of environmental biology / Academy of Environmental Biology, India》2007,28(3):645-650
The actinomycete strain LA-29 isolated from the gut contents of the fish, Mugil cephalus of the Vellar estuary showed excellent L-asparaginase activity The enzyme was purified 18-fold and the final recovery of protein was 1.9%, which exhibited an activity of 13.57 IU/mg protein. The partially purified L-asparaginase inhibited the growth of leukemia cells in male wistar rats. Average survival period of the rats was more in an optimum enzyme dose of 100 units and the survival period was less when the dosages were increased and at the same time the enzyme became less effective when the dosages were decreased. Higher survival of 17.2 days was recorded when 100 units of the enzyme was given in three intermittent doses (50/25/25 units) at the interval of 24 hr. Analysis of cell components of the strain LA-29 has revealed the wall type-I which is the characteristic of the genus Streptomyces. Further the morphological, physiological and biochemical features along with the micromorphological results obtained for the strain LA-29 were compared with that of the Streptomyces species found in Bergey's Manual of Determinative Bacteriology and the strain LA-29 has been tentatively identified as Streptomyces canus. 相似文献
809.
Female and male reproductive interests often differ. In species in which matings are accompanied by a transfer of resources
valuable for both participants, such as nuptial prey gifts, conflicts may readily occur. Scorpionflies may use alternative
mating tactics. One is to offer a prey item (dead arthropod) to females in exchange for mating. This prey gift tactic includes
a conflict because a male must decide on whether to offer the gift rather than to fight the female and consume the gift. The
outcome may depend on the nutritional status of both males and females. Males may be more willing to give if they themselves
are satiated and the condition of the females may influence the payoff from the males’ investment. Similarly, females may
be more willing to accept food gifts if they are in poor nutritional condition. In this study of the scorpionfly Panorpa cognata, I experimentally manipulated the feeding history of both males and females. I observed the outcome of the direct interactions
that followed when males that were holding prey were approached by females. I found that well-fed males offered the food gift
sooner than males in poor nutritional condition that fed extensively on the food item before offering. Female condition had
no significant influence on whether prey items were offered by males or accepted by females. I also found that well-fed males
rarely searched for prey to pursue the prey gift tactic in courtship. Thus, the prey tactic does not seem to be the males’
first option. 相似文献
810.
Pooja?PalEmail author Himangana?Gupta Deepak?Kapur 《Mitigation and Adaptation Strategies for Global Change》2016,21(3):391-402
Steel dominates the global metal production accounting for 5 % of increase in Earth’s atmospheric carbon dioxide (CO2). Today, India is the 4th largest producer of crude steel in the world. The sector contributes around 3 % to the country’s gross domestic product (GDP) but adds 6.2 % to the national greenhouse gas (GHG) load. It accounts for 28.4% of the entire industry sector emissions, which are 23.9% of the country’s total emissions. Being a developing country, India is not obliged to cut its emissions under the Kyoto Protocol to the United Nations Framework Convention on Climate Change (FCCC), but gave voluntary commitment to reduce the emission intensity of its GDP by 20–25 % from the 2005 level by 2020. This paper attempts to find out if the Indian steel sector can help the country in fulfilling this commitment. The sector reduced its CO2 emissions per ton of steel produced by 58% from 1994 to 2007. The study generates six scenarios for future projections which show that the sector can reduce its emission intensity by 12.5 % to 63 %. But going by the conservative estimates, the sector can reduce emission intensity by 30 % to 53 %. However, actual emissions will go up significantly in every case. 相似文献