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81.
River Sabarmati is one of the biggest and major river of Gujarat that runs through two major cities of Gujarat, Gandhinagar and Ahmedabad and finally meets the Gulf of Khambhat (GoK) in the Arabian Sea. A study was conducted to evaluate the water quality of this river, as it could possibly be one of the major sources for filling up Kalpasar, the proposed man-made freshwater reservoir supposed to be the biggest one in the world. A total of nine sampling stations were established covering 163 km stretch of the river from upstream of Gandhinagar city to Vataman near Sabarmati estuary. Physicochemical (temprature, pH, salinity, chloride, total dissolved solids, turbidity, dissolved oxygen, biochemical oxygen demand, phenol, and petroleum hydrocarbons), biological (phytoplankton), and microbiological (total and selective bacterial count) analyses indicated that the river stretch from Ahmedabad-Vasana barriage to Vataman was highly polluted due to perennial waste discharges mainly from municipal drainage and industries. An implementation of sustainable management plan with proper treatment of both municipal and industrial effluents is essential to prevent further deterioration of the water quality of this river.  相似文献   
82.
A series of novel N-alkyl-N-[1-(2-hydroxyphenyl) ethyl]amines were synthesized as potential new agents to control pests. Their structures were confirmed on the basis of IR, NMR and elemental analyses. Six new N-alkyl-N-[1-(2-hydroxyphenyl) ethyl]amines were prepared by reduction of corresponding Schiff bases using sodium borohydride in 80–87 % yields. These compounds were tested for their antifungal activity against two pathogenic fungi viz., Rhizoctonia bataticola ITCC 0482 and Sclerotium rolfsii ITCC 5226 and for insecticidal activity against insects of stored grain pest Callosobruchus analis. Fungicidal bioassay revealed that compound N-Decyl-N-[1-(2-hydroxyphenyl)ethyl]amine, was highly effective against R. bataticola (ED50 6.86 mg L?1) which was comparable with that of commercial fungicide hexaconazole (ED50 6.35 mg L?1). Also compounds N-Heptyl-N-[1-(2-hydroxyphenyl)ethyl]amine, N-Octyl-N-[1-(2-hydroxyphenyl)ethyl]amine and N-Nonyl-N-[1-(2-hydroxyphenyl)ethyl]amine displayed promising fungitoxicity against same pathogen. However, compound N-Heptyl-N-[1-(2-hydroxyphenyl)ethyl]amine was also found to be effective against S. rolfsii (ED50 4.92 mg L?1 as against 1.27 mg L?1 for hexaconazole). Compound N-Hexyl-N-[1-(2-hydroxyphenyl)ethyl]amine was most effective as insecticide followed by compound N-Octyl-N-[1-(2-hydroxyphenyl)ethyl]amine. LC50 values for these compounds were 155.0 and 275.0 mg L?1 respectively as against 36.70 mg L?1 for commercial insecticide dichlorovos. The results obtained from bioassays indicate that this class of compounds can be utilized for the design of new substances endowed with pesticidal activities.  相似文献   
83.
In the present investigation, bioefficacy of developed β-cyfluthrin formulations, utilizing laboratory synthesized poly(ethylene glycols) based amphiphilic copolymers, were evaluated against Callosobruchus maculatus (Coleoptera: Bruchidae). The bioefficacy data indicated that the formulations developed by utilizing polymers having PEG – 1500 (3c) and PEG – 2000 (3d) as the hydrophilic segment showed greater efficacy after 14 days as evident from EC50 values (2.2 and 1.58 mg L?1 respectively). Also, release from the commercial SC formulation was faster than developed formulations as the commercial formulation had the lowest EC50 value on the first day (0.51 mg L?1). The mean EC50 of the commercial formulation against C. maculatus was quite high as compared to those of developed formulations. The results suggest that depending upon the polymer matrix used, the application rate of β-cyfluthrin can be optimized to achieve insect control at the desired level and period. The results described in this paper are promising and provide a comparison of developed formulations with the commercial one showing an earlier degradation of β-cyfluthrin in the latter and relatively prolonged activity in the former.  相似文献   
84.
Artificially roughened solar air heater has been topic in research for the last 30 years. Prediction of heat transfer and fluid flow processes of an artificially roughened solar air heater can be obtained by three approaches: theoretical, experimental, and computational fluid dynamics (CFD). This article provides a comprehensive review of the published literature on the investigations of artificially roughened solar air heater. In the present article, an attempt has been made to present holistic view of various roughness geometries used for creating artificial roughness in solar air heater for heat transfer enhancement. This extensive review reveals that quite a lot of work has been reported on design of artificially roughened solar air heater by experimental approach but only a few studies have been done by theoretical and CFD approaches. Finally this article presents a comparative study of thermo-hydraulic performance of 21 different types of artificial roughness geometries attached on the absorber plate of solar air heater in terms of thermo-hydraulic performance parameter. Heat transfer and friction factor correlations developed by various investigators for different types of artificially roughened solar air heaters have also been reported in this article.  相似文献   
85.
86.
A survey of lead pollution in Chhattisgarh State, central India   总被引:2,自引:0,他引:2  
Lead (Pb) is of major environmental concern due to its toxicological importance. The anthropogenic emission of Pb is at least 100 times higher than natural emissions. Soil and dust are significant sources of Pb exposure. Lead is generally immobile in soil and accumulates in the upper layers. Lead particles may enter homes via shoes, clothes, pets, and windows. Central India is rich in deposits of natural resource materials such as coal, pyrite, dolomite, and alumina that contain Pb and other heavy metals at the trace levels, and the substantial exploitation of these materials has tended to increased contamination of water and geological formations. Here we present data on Pb concentrations in the water, soil and sediment samples (n=158) collected from 70 locations in Chhattisgarh state, Raipur region. Lead concentrations in the surface water (n=44), groundwater (n=44), soils (n=60) and sediments (n=10) ranged from 6 to 1410, 3 to 52, 12.8 to 545, and 31 to 423 μg g−1, with mean values of 305, 16, 102 and 190 μg g−1, respectively. Most of the Pb fractions of >80% can be leached out with the chemical extractants EDTA, acetic acid, and hydroxylamine hydrochloride. Lead has accumulated in the soil clay fraction due to its relatively large surface area and decreases with increasing depth in the soil profile.  相似文献   
87.
Ultrasonography was performed during the second trimester (17 weeks) in a pregnancy at risk for osteogenesis imperfecta congenita (OI). The scan showed that the femur was short, bent and dense. Radiologic examination of the fetus after interruption of pregnancy showed typical X-ray changes of OI.  相似文献   
88.
89.
Environmental Science and Pollution Research - Warming of the earth is considered as the major adverse effect of climate change along with other abnormalities such as non-availability of water...  相似文献   
90.
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