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Chak Āzam Saffo, Pakistan

Khan S.A.,Kohat University of Science and Technology | Ali H.,Quid i Azam University | Ihsan A.,NIBGE | Sabir N.,Government College University at Faisalabad
Colloid Journal | Year: 2015

The aim of the study was to control the size of gelatin nanoparticles under varied conditions of nanoprecipitation. The gelatin concentration in the solvent phase and different combination of nonsolvents was used to see influence on the size, polydispersity and recovery yield of produced nanoparticles. The size of the nanoparticles was determined by dynamic light scattering. The yield of gelatin nanoparticles after freezedrying was found gravimetrically. The morphology of nanoparticles was studied by scanning electron microscopy. The results suggest that the size of nanoparticles can be tuned within a range 250–350 nm with low polydispersity index because of the inhibition of particle aggregation during crosslinking. The produced nanoparticles are of spherical shape with a smooth surface. We found that the recovery yield was also dependent on the gelatin concentration in the solvent phase. © 2015, Pleiades Publishing, Ltd.

Ullah H.,Kohat University of Science and Technology | Khattak N.U.,University of Peshawar | Fozia,Khyber Medical University | Ali N.,PINSTICS | And 4 more authors.
Journal of the Chemical Society of Pakistan | Year: 2013

Fission Track Technique has been applied for the estimation of uranium in 30 drinking water sources of Tehsil Takht-e-Nasrati and District Karak, Pakistan. These samples have mean, minimum and maximum concentration of uranium of 13.45 ± 3.207, 1.07 ± 0.6, 84.23 ± 15.63 μg l -1, respectively. The significant finding was the observation of very high level of uranium in drinking water sources obtained from uranium rich bedrocks than the safe limit of WHO (15 μg l-1) for human consumption. On the basis of this study, it was concluded that the origin of uranium is potentially due to one of the Asia richest mineral deposit of uranium in Union council (UC) Shanawa Gudi Khel (Karak, Pakistan). The results could be of vital concern in diagnosis and prognosis of uranium induced disease in the local population under investigation.

Ud Din A.,Kohat University of Science and Technology | Abdel-Reheem M.A.T.,King Saud University | Abdel-Reheem M.A.T.,Ain Shams University | Ullah H.,Quid i Azam University | And 4 more authors.
Life Science Journal | Year: 2013

Objectives: Onion and potato (Allium cepa and Solanum tuberosum) are most commonly used vegetables in Pakistan. Different samples of local variety of onion and potato were collected from Khyber Pakhtunkhwa, Pakistan and few samples imported from Afghanistan. Methods: Heavy metal contents of these vegetable were analysed for Cr, Pb, Cu, Co, Zn, Mn, Fe, Ni and Cd using atomic absorption spectroscopy. Results: The order of metal contents was found to be Fe > Zn > Mn > Cu > Cr > Pb > Cd > Ni > Co in onion (local variety), and a similar pattern Zn > Fe > Cu > Mn > Pb > Ni > Cr > Cd was also observed in onion (imported variety). Conclusion: Higher content of Fe Zn were found in onion from Pakistan and Afghanistan respectively. Metal levels observed in vegetables were compared with WHO and established permissible levels reported by different authors. Mean concentration of Fe, Zn, Mn, Cu, Pb, Cr, Ni, Cd and Co are 45.9, 37.63, 6.76, 5.78, 2.26, 1.623, 0.745, 0.636 and 0.0950 respectively. The study concludes that the cultivation, transportation and marketing systems of vegetables may play a significant role in elevating the contaminant levels of heavy metals which may pose a threat to the quality of the vegetables with consequences for the health of the consumers of locally produced foodstuffs. The distribution and characterization of heavy metals in vegetables was studied in detail and discussed in this paper.

Rana S.M.,Quid i Azam University | Khan E.A.,Quid i Azam University | Yaqoob A.,Quid i Azam University | Latif A.A.,Lahore College for Women University | Abbasi M.M.,Quid i Azam University
Journal of Medical Entomology | Year: 2014

ABSTRACT In southern Punjab, Pakistan, Muzaffargarh District is known to have insecticideresistant Anopheles and drug-resistant Plasmodium spp. In this part of the country, five anopheline mosquitoes, Anopheles stephensi Liston, Anopheles culicifacies Giles, Anopheles fluviatilis James, Anopheles superpictus Grassi, and Anopheles subpictus Grassi (Diptera: Culicidae) are known as malaria vectors. Among these, An. culicifacies is the primary and An. stephensi is the secondary malaria vector. Outbreaks of malaria usually occur after rainy episodes. We conducted field surveys to collect field strains of An. culicifacies and An. stephensi mosquitoes from different areas of Muzaffargarh District. We determined susceptibility and irritability levels of their adult stages to the discriminative dose of different insecticides. For this purpose, we used World Health Organization's established criteria for assessment. Mortality was calculated after 1 h exposure and for 24 h recovery period for various insecticides. An. stephensi was found to be significantly resistant to dichlorodiphenyltrichloroethane (DDT, an organochlorine), dieldrin (a chlorinated hydrocarbon), and malathion (organophosphorus), with lethal times (LT50) of 83.17, 52.48, and 37.53, respectively. However, the species was significantly sensitive to permethrin, deltamethrin (pyrethroids), and fenitrothion (organophosphate) with LT50 of 2.85, 2.34, and 13.18, respectively. Among these, permethrin showed more promising results against adult An. stephensi. When analyzed for irritancy, we found that among pyrethroids, permethrin was the most irritant insecticide for both An. stephensi and An. culicifacies. DDT and dieldrin showed least irritancy with 0.42 ± 0.08 and 0.77 ±0.12 takeoffs per minute per adult, respectively, against An. stephensi. The mean number of takeoffs per minute per adult with permethrin showed significant irritancy for permethrin when compared with DDT. Based on this study, we conclude that the use of organochlorine (DDT) and chlorinated hydrocarbon (dieldrin) should not be reintroduced in Malaria Control Programme in Pakistan until there is enough evidence to do so at any stage in future, and the use of pyrethroids should continue, with preference to permethrin for better control of malaria by indoor residual spraying. © 2014 Entomological Society of America.

Majeed I.,Quid i Azam University | Nadeem M.A.,Quid i Azam University | Nadeem M.A.,SABIC | Al-Oufi M.,SABIC | And 6 more authors.
Applied Catalysis B: Environmental | Year: 2016

Photo-catalytic hydrogen production has been studied on Au supported CdS catalysts under visible light irradiation in order to understand the effect of Au particle size as well as the reaction medium properties. Au nanoparticles of size about 2-5nm were deposited over hexagonal CdS particles using a new simple method involving reduction of Au3+ ions with iodide ions. Within the investigated range of Au (between 1 and 5wt.%) fresh particles with mean size of 4nm and XPS Au4f/Cd3d surface ratio of 0.07 showed the highest performance (ca. 1 molecule of H2/Auatoms-1) under visible light irradiation (>420nm and a flux of 35mW/cm2). The highest hydrogen production rate was obtained from water (92%)-ethanol (8%) in an electrolyte medium (Na2S-Na2SO3). TEM studies of fresh and used catalysts showed that Au particle size increases (almost 5 fold) with increasing photo-irradiation time due to photo-agglomeration effect yet no sign of deactivation was observed. A mechanism for hydrogen production from ethanol-water electrolyte mixture is presented and discussed. © 2015 Elsevier B.V.

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