Journal of Science and Technology

Author(s):MOHAMMAD SALEEM KHAN, RAHMAT GUL

Abstract :

Abstract: Conductance study of various conducting polymer electrolyte systems consisting of Poly (vinyl chloride) as the host polymer, with lithium per chlorate (LiClO4), ZnO and ZrO2 as added salts is presented here. The solid polymer electrolytes were prepared by employing solution casting method. The ionic conductivity of polymer electrolyte systems has been investigated by using impedance spectroscopy technique at a wide range of temperature. Various systems showed different conductance behavior. Among the two added salts i.e. ZnO and ZrO2 electrolyte system of ZrO2 showed highest conductivity values at room temperature. The addition of single plasticizer enhanced the conductance in this system. The conductance trend in these systems at room temperature was as: PVC – ZrO2-EC-LiClO4, PVC – ZnO – LiClO4.

Author(s):MOHAMMAD NAFEES, NAZISH KHAN, SHAH RUKH, ADILA BASHIR

Abstract :

Abstract: The present study was conducted to investigate the various essential micro-nutrients and non essential heavy metal concentrations in different sources of salts available in Pakistan. Objective of this study was to know about the nutrient status and potential hazards (if any). There are two types of salts available in the market, sea/lake salt and rock salt. Chemical analyses were carried out in order to know their characteristics. For this purpose, seven samples were collected from different areas of Pakistan and were analyzed for four essential elements (Fe, Zn, Mn and CO) and three non essential heavy metals (Cu, Cd and Ni). The results were compared with permissible limits of WHO required for normal body functions. The edible grade of Khewra appeared to be enriched in Fe with 21.182 mg/kg. Gawadar sea salt was found to be rich in Zn with 28.61 mg/kg. Cobalt was found in Karachi Sea salt and Khewra edible grade with 10.02 and 10.01 mg/kg, respectively. Similarly, the concentrations of non essential heavy metals, like Cu, Cd and Ni were found to be comparatively high in Khewra salt with the average value of 4.04, 79.75 and 8.20 mg/kg, respectively. By comparing the rock and sea salts with different standards, it can be concluded that the concentration of various non essential heavy metals is within the permissible limit. Comparing the two sea salts (Karachi and Gawadar), the concentration of non-essential heavy metals was comparatively less in Gawadar sea salts. T

Author(s):AMJAD ALI, AMIR NAWAZ KHAN, SHAH NAWAZ KHAN

Abstract :

Abstract: The Earthquake–2005 completely destroyed the town of Balakot. The site of town has been declared as red zone and new town is proposed at Bakryal which is 22 and 15 km away from old Balakot town and Mansehra, respectively. The site analysis shows that this new town is well-planned and offering advanced utilities & services infrastructure with very low vulnerability to hazards. The site of the new town attracts the low income and public servant class of the of old Balakot town as well as the elite class of the region for residential purposes. However, economic, social and political interests of the business and landowners classes of the old town are feared to suffer. As a result, these groups of the Balakot community resist the process of resettlement. The residential plots are allotted to the residents of the old town. However, most of the residents are least interested in the new town. This situation encourages the real estate business in the new town. The site, situation and resettlement process differently affected the growth of proposed new town. The new town has huge capacity for growth and development. Initially, the property business and high level of non-basic activities and later on the favourable environment for basic activities will support the growth and development of this new town.

Author(s):NAHEED ALI, RUHI NAZ, KHALID KHAN, LUBNA

Abstract :

Abstract: This study aims to deduce the temporary habitat of mosquitoes, and their seasonal dynamics in Peshawar University campus in selected sites. Monthly sampling of mosquito larvae from six habitats was carriedout from May to December, 2009. The habitats selected for this survey were; bamboo traps, discarded drinks cans, small wastewater channels, mud pots, tyres and a small cemented pond. A total of 2419 adult mosquitoes comprising 1433 females and 985 males belonging to six species viz. Aedes albopictus (57.2%), Aedes unilineatus (2.5%), Aedesw-albus (2.8%), Armigeres subalbatus (3.8%), Culex quinquefasciatus(33.6%) and one individual of Anopheles stephensi were recorded. As for as density and distribution of the recovered species are concerned, Aedes albopictus was found to be dominant and frequent, recorded from four out of six habitats. The highest number was recorded in September and October while lowest in the month of May. Culex quinquefasciatus was the second most abundant species collected from three habitats with dominant status and moderate distribution. Aedes unilineatus, Armigeres subalbatus and Aedes w-albus were noted as subdominant species with the former two species infrequent and later sporadic in distribution. Larvae of Aedes mosquitoes were found in all habitats except pond water and tyres. Monthly distribution reveals that Aedes albopictus and Culex quinquefasciatus, during this survey were found through out the study period fr

Author(s):MUZAFFAR AHMAD KHAN, MOHAMMAD NAFEES, SHAH NAWAZ KHAN,

Abstract :

Abstract: This study was conducted on Taru-Jabba housing scheme which was designed without Environmental Impact Assessment (EIA). In Pakistan, for housing schemes Initial Environmental Examination (IEE) study is compulsory but exempted from detail EIA and periodic monitoring. It is a general perception that EIA focus on impacts of human on environment. Impacts of environment on human is usually not considered in EIA. In this paper, an attempt has been made to know about the present status of ongoing construction and environment. The main focus is on availability and quality of water and its effects on residents. For this purpose, drinking water from different sources were characterized for physical and chemical parameters and compared with water quality guidelines standards. It was found that water quality of dug-well is not complying drinking water quality standards. Water quality of tube-well was comparatively good. It was concluded that the ground water will affect the health of local residents. It was, therefore, recommended to make periodic monitoring mandatory for housing schemes and make necessary arrangement for providing tube-well water to all the residents.

Author(s):QAMRUZ ZAMAN, FAZL-E-RAZIQ , MUHAMMAD IQBAL, SALAHUDDIN

Abstract :

Abstract: Most of the data sets regarding survival analysis contain ties and censored events. The earlier methods do not take in to account the presence of these events and provide misleading results. In the present study, a method of Bootstrap survival function and its variance estimator by considering the ties among the events and censored observation is proposed. The performance of proposed method is checked by conducting simulations and compared with the existing methods. The results demonstrates that the proposed method perform better as compared to the earlier methods. Therefore, it is suggested that the proposed method be considered for the analysis of such types of data sets.