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Abstract : Mineralogical Investigation of the Bara Formation from Lakhra Anticline, Sindh province, Pakistan
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Abstract: The present study shows the bulk mineralogical composition of the Bara Formation from Lakhra anticline, near to Lakhra coalfield area of the Sindh province of Pakistan. The petrography, scanning electron microscope and X-ray diffractommeter were used for the detailed mineralogical investigations. Quartz, feldspars, hematite, gypsum, chlorite and goethite minerals were obtained from above methods. Quartz, feldspar and chlorite minerals indicated that the sediments were transported from igneous and metamorphic rocks and the hematite and goethite indicated the continental environment for the studied formation. Mineralogical investigation of the Bara Formation indicates that the sediments were supplied from the Igneous and metamorphic rock terrane. It can be said that the Bara formation sediments were supplied from the Igneous and metamorphic complex which is exposed in the southeastern part of the studied area. Keyword: Bulk Mineralogy, Bara Formation, Lakhra, Quartz, XRD and SEM. Download Full Article |
Abstract : Study of Variations in the Extraction Yield, Phenolic Contents and Antioxidant Activities of the Bark of F. religiosa as a Function of Extraction Procedure
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Abstract: In present study, the effect of different solvents and multiple techniques on the extraction yield, phenolic contents and antioxidant activities of bark of F. Religiosa, was investigated. Four solvents (absolute ethanol, absolute methanol, 80% aqueous ethanol and 80% aqueous methanol) and three techniques (orbital shaker, sonication and magnetic stirrer) were applied for this purpose. The extract obtained by the application of 80% methanol, exhibited significantly (p<0.05) higher antioxidant activities. The statistical order of the solvents according to their efficiency was 80% methanol > 80% ethanol > absolute methanol >absolute ethanol. As for as techniques are concerned, the extracts obtained by the application of sonication demonstrated significantly (p<0.05) higher antioxidant activities as compared to to the extracts obtained as a result of using magnetic stirrer and orbital shaker. Keyword: Antioxidant activities, DPPH radical, Ficus religiosa, total phenolic contents. Download Full Article |
Abstract : A Study of Anomalous Wet and Dry Years in the Winter Precipitation of Pakistan and Potential Crop Yields Vulnerability
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Abstract: Pakistan experiences distinctively large rainfall variability on spatial as well as temporal scales. On spatial scale the rainfall variability is mainly caused by its peculiar topographic features encompassing from south to north of the country. On the other hand the temporal rainfall variability sometimes exceptionally large, does affect the climate of the country that in turn impacts the climate-dependent sectors like agriculture, hydroelectric power generation and ecology. In this study the 30-year winter season (December-March, DJFM) rainfall data of 35 meteorological sites of Pakistan have been analysed to identify the anomalous wet and dry years, their potential impact on crop yields across Pakistan and vulnerability of climate. The National Centre for Environmental Prediction (NCEP), US reanalysis data are used to investigate the association of the surface and upper air atmospheric circulation features responsible for anomalous wetness and dryness. This study may prove of some help for an improved winter rainfall prediction tool and better management of available water resources viz-a-viz optimal crop yields production. Keywords: Winter rains, Anomalous wetness/ dryness, NCEP reanalysis, Agriculture yields. Download Full Article |
Abstract : Synthesis and Structural Studies on MgO Nanoparticles Suitable for Tunnel Barrier Applications
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Abstract: Magnesium oxide (MgO) nanoparticles are synthesized by a simple coprecipitation method. XRD studies reveal that nanoparticles are predominantly (100) textured with an average crystallite size of 19 nm.The relative peak intensities for (100) and (110) textured grains i.e., I(100)/I(110) is found to be ~ 2. Scanning electron microscope (SEM) pictures of our samples indicate that our synthesized nanoparticles are spherically shaped. Due to excellent electron tunneling features of (100) textured MgO nanoparticles, our synthesis method is suitable for cost effective and simple synthesis of pure MgO nanoparticles for applications involving electron tunneling. Keywords: Metallic oxide, MgO, Nanoparticles, chemical synthesis, tunnel barrier.. Download Full Article |
