A Workflow Scheduling Method for Cloud Computing Platform

Wireless Personal Communications - Scheduling in computing environments such as homogeneous and heterogonous is very challenging and faces various difficulties computationally. This computing needs...     

Peat swamps at Giral lignite field of Barmer basin,Rajasthan, Western India: understanding the evolution through petrological modelling

International Journal of Coal Science & Technology - The lignite samples collected from Giral lignite field of Barmer basin have been subjected to petrological investigation. The data generated...     

Understanding the paleomires of Eocene lignites of Kachchh Basin,Gujarat (Western India): petrological implications

International Journal of Coal Science & Technology - The present paper entails the results of the investigations carried out on the lignite deposits of Kachchh Basin. The lignite samples were...     

Repeated oral dose toxicity of iron oxide nanoparticles: biochemical and histopathological alterations in different tissues of rats

Iron oxide (Fe2O3) nanoparticles are widely used in different fields of nanotechnology. However, studies on its toxicological effects in humans and the environment are scarce. Therefore in this investigation 28 days repeated dose oral toxicity studies were conducted on Fe2O3-30 nanoparticles and its counterpart Fe2O3-Bulk with special reference to target biochemical enzymes and histopathological changes in different tissues of female albino Wistar rats. The alterations observed after Fe2O3-30 treatment in various tissues of exposed rats were dose dependent. Low dose was less effective than medium and high doses with low dose demonstrating "no observed adverse effect" (NOAEL). Further, high dose treated rats showed toxic sign and symptoms but no mortality. Due to the repeated doses of Fe2O3-30 nanoparticles, significant inhibition was observed in total, Na(+)-K+, Mg2+ and Ca(2+)-ATPases in brain of exposed rats. Similarly, significant inhibition was recorded in RBC and brain acetylcholinesterase indicating that both synaptic transmission and nerve conduction were affected by this compound. Fe2O3-30 significantly increased aspartate amino transferase, alanine amino transferase and lactate dehydrogenase in serum and liver, whereas, these enzymes were significantly decreased in kidney indicating tissue necrosis and possible leakage of these enzymes into the blood stream. Increased levels of these enzymes in liver as well as in serum might be an adaptive mechanism due to the stress of iron nanoparticles. High dose treated rats of Fe2O3-30 showed dilated central vein, perivascular round cell collections in liver along with focal areas of necrosis, whereas kidney showed focal tubular damage and red pulp congestion, whereas prominent white pulp indices were observed in spleen. However, histopathological analysis of heart and brain tissues failed to show any adverse changes in their architecture exposed to repeated doses of Fe2O3-30 when compared with controls. Fe2O3-Bulk did not induce any adverse effects in either biochemical parameters or histopathology in the treated rats and the changes observed were near to controls and mostly insignificant, indicating that the counter part of nanoparticles i.e., bulk material is less potent than the nanoparticles in causing toxicity in the exposed animals. These results suggested that as particle size decreases, this iron nanoparticle showed increased toxicity, even though the same material is relatively inert in bulk form. The changes observed in these target enzyme activities could be useful as biomarkers of exposure to nanoparticles.     

Geochemistry of Kasnau-Matasukh lignites,Nagaur Basin,Rajasthan (India)

International Journal of Coal Science & Technology - The distribution and verticals variation of geochemical components in the Kasnau-Matasukh lignites of Nagaur Basin, Rajasthan, were...     

Strength characteristics and stability analysis of GGBS stabilised fly ash-overburden dump

ABSTRACT

Stability of OB dump slope has been a major concern and require a proper design for safe mining operation. Utilisation of fly ash with OB material for construction of mine haul road and external dumping, may provide an alternative mode of fly ash disposal. In this study, fly ash was mixed with OB material at different percentages to evaluate the compaction characteristics, California Bearing Ratio (CBR), Unconfined Compressive Strength (UCS) and shear strength parameter. Tests were also performed with the addition of a different percentage of Ground Granulated Blast Furnace Slag (GGBS) with fly ash-OB mix. Further, the effects of GGBS at various curing period on CBR and UCS characteristics were highlighted. Numerical modelling was carried out for dump containing OB material, fly ash and GGBS at different proportions to evaluate the Factor of Safety (FoS) and to suggest the optimum dump geometry. Experimental result infers that maximum CBR and UCS values were obtained for 78% OB material, 10% fly ash and 12% GGBS at 28 days curing period. Based on the observed FoS from numerical modelling, an optimal multiple regression model and artificial neural network model have been suggested for the direct prediction of FoS by various input parameters.     

Fabrication and investigation of influence of CaCO3 as foaming agent on Al-SiCp foam

Closed cell aluminum foams have been used in various disciplines of engineering. Aluminum foams provide high strength with the advantage of low weight. In the current research, CaCO₃ is used as a foaming agent for producing closed-cell aluminum foams. For the fabrication of homogenous foam, optimization of process parameters was done. The effect of SiC as a thickening agent on structural property of foams viz. density and porosity have been inspected. Foams with density 0.40–0.86 g/cm³ were produced. The produced foams were studied under axial compression tests for evaluating mechanical properties. It can be inferred from the results that by adding 3 wt.% CaCO₃, the uniform viscosity of melt was achieved and a homogeneous foam structure is achieved with optimum porosity. Also, 5 wt.% addition of CaCO₃ in melt and stirring speed at 1400 rpm tend to increase porosity and decrease cell wall thickness. The optimum values for thickening agent SiC, foaming agent CaCO₃ at stirring speed 1400 rpm were found out to be 15 wt.%, 3 wt.%. The effect of relative density, the addition of thickening and foaming agent is studied.     

Mechanism and Kinetics of Separation of Oil From Oil-in-Water Emulsion by Air Flotation

The authors investigate the application of air flotation for the removal of oil from oil-in-water emulsion using a flotation column of diameter 3.5 cm and height 106 cm. Several parameters affecting the separation efficiency such as effect of adding sodium chloride, effect of flotation time, and effect of air flow rate were investigated. The experimental data were also analyzed in terms of first-order kinetic rate model. Using this model flotation constant k and correlation coefficient r were determined. An equation relating flotation rate constant and the concentration of sodium chloride was developed. The maximum oil removal efficiency at optimized operating condition was found to be around 98.23%.