排序方式: 共有36条查询结果,搜索用时 15 毫秒
31.
Shah MH Iqbal J Shaheen N Khan N Choudhary MA Akhter G 《Environmental monitoring and assessment》2012,184(3):1243-1252
Selected trace metals were estimated by atomic absorption spectrometry in the water and soil samples collected from the remote
region of Himalaya. The soil samples were analysed for soluble and acid extractable fraction of trace metals. In water samples,
Ca, Na, Mg and K emerged as dominant contributors, whereas, Ca, Na, K, Mg, Fe and Pb were estimated at comparatively higher
levels in the water extract of the soil. In case of acid extract of the soil samples, Ca, K, Fe, Mg, Mn and Na were found
at elevated concentrations. Based on mean levels of the metals, following decreasing concentration order was observed in water
samples: Ca > Na > Mg > K > Pb > Co > Cu > Zn > Mn > Cr > Fe > Cd > Li, however, in the acid extract of the soil, following
order was noted: Ca > K > Fe > Mg > Mn > Na > Pb > Zn > Cr > Li > Cu > Co > Cd. The correlation study revealed appreciably
diverse mutual relationships of trace metals in the water and soil samples. The multivariate cluster analyses exhibited divergent
apportionment of trace metals in water and soil samples. Among the trace metals, Cd, Pb, Li, Zn, Cr, Cu, Mn and Co exhibited
extreme to significant anthropogenic enrichment in the soil samples, while the rest of the metals were mostly contributed
by the natural processes. 相似文献
32.
Guvvala Pushpa Rani Sellappan Selvaraju Parameswaraiah Ravindra Janivara 《Environmental science and pollution research international》2016,23(18):18200-18210
Environmental Science and Pollution Research - The arsenic (As) is a multi system effector including reproduction. The present study examined the association of graded doses of As(V) on testicular... 相似文献
33.
Choudhary S 《Journal of environmental biology / Academy of Environmental Biology, India》2003,24(4):493-494
Experiments were conducted by using nicotine (plant extract) for its toxic effects on Drosophila melanogaster, LC50 estimated is 2.9552 microl/100 ml. Studies revealed that nicotine affects adult emergence of males and females (sex-ratio) of mutant form (Yellow) of Drosophila melanogaster. 相似文献
34.
Residues dynamics of Endosulfan (525.00 g a.i. ha(-1)), Imidacloprid seed treatment (21 g a.i. kg(-1)), Lambdacyhalothrin (75.00 g a.i. ha(-1)) and Spiromesifen (225.00 g a.i. ha(-1)) in nectar and pollen of mustard, Brassica juncea (L.) Czern. grown in Himachal Pradesh (India) were determined through bioassay (using Drosophila melanogaster Meig. as test organism) and GC (Gas chromatographic) and HPLC (High performance liquid chromatographic) methods. In general chromatographic methods were more sensitive for the determination of above given pesticides compared to bioassay method. Average recoveries in nectar samples varied between 82.85 and 88.90% by bioassay and 91.20 and 93.55% by chromatographic techniques. In pollen samples, recoveries varied between 81.44 and 86.44% by bioassay and 88.50 and 91.30% by chromatographic methods. Imidacloprid residues were neither found in nectar nor in pollen samples at the time of sampling i.e. 50% of flowering. The order of average half life of residues was: Lambdacyhalothrin (12.45 h) < Spiromesifen (19.99 h) < Endosulfan (27.49 h) for nectar and Spiromesifen (9.69 h) < Lambdacyhalothrin (12.44 h) < Endosulfan (17.84 h) for pollen samples. It was found that Imidcloprid seed treatment was practically harmless to honey bees, whereas a waiting period of 5 days must be observed on crops sprayed with these chemicals during blooms to avoid any accidental hazards to honey bees. 相似文献
35.
Akhilesh Kumar Choudhary H. Chelladurai C. Kannan 《International Journal of Green Energy》2016,13(13):1369-1379
The increasing consumption and excessive extraction of conventional fuels is the matter of serious concern. Nowadays, world is looking for alternative sources of fuel which can partially replace conventional fuel dependence. The current investigation intends to provide evaluation of bio-ethanol preparation from Water Hyacinth (WH) and its influence on diesel engine performance under various operating conditions. This study explores the extraction of glucose from WH (Eichhornia crassipes) pretreated with sulfuric acid (H2SO4) for production of bio-ethanol. For the production of bio-ethanol different concentrations of H2SO4 acid hydrolysate (1%, 2%, 4%, 6%, 8%, and 10%) were prepared which was then followed by fermentation with cellulose fermenting yeasts. From results, it was observed that 4% H2SO4 acid hydrolysis produces higher concentrations of ethanol than other concentrations. Bio-ethanol extracted from WH was blended with diesel in different proportions (5%, 10%, 15%, 20%, and 25%) v/v and performance and emissions were experimentally investigated on single cylinder diesel engine under various load conditions. Experimental results show that 5 BED [5% bio-ethanol (WH + 95%diesel v/v) and 10BED (10% bio-ethanol (WH + 90%diesel v/v)] produces higher brake power, brake thermal efficiency and brake mean effective pressure with improved exhaust emission profiles than any other blend. 相似文献
36.
Tripathi Shweta Choudhary Sonia Meena Alok Poluri Krishna Mohan 《Environmental Chemistry Letters》2023,21(4):2085-2128
Environmental Chemistry Letters - Global warming is induced partly by rising atmospheric carbon dioxide levels, calling for sustainable methods to sequester carbon. Here we review carbon capture,... 相似文献