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۱Assessing the Financial Failure Using Z–Score and Current Ratio: A Case of Sugar Sector Listed Companies of Karachi Stock Exchange
اطلاعات انتشار: World Applied Sciences Journal، بيست و سوم،شماره۶، ۲۰۱۳، سال
تعداد صفحات: ۸
Since 1968, after the development of multivariate model, financial health of the corporate sector to predict their financial failure is heavily studied. Altman Z–Score is the most efficient model to judge the financial failure of the companies. This study uses Altman’s Z–Score and current ratio to assess the financial status of sugar sector companies listed at Karachi stock exchange. Sugar sector is the second largest slice among all sectors listed at Karachi stock exchange. Total population sampling technique was used in this study and all thirty five sugar sector listed companies at KSE were included in this study to get the deep insights of the issue. State bank’s balance sheet analysis and companies’ financial reports were used to compile the data for the years 2009 and 2010. The results of the study showed that current ratio and Altman’s Z–Score are the reliable tool of assessing financial health of sugar sector listed companies of Karachi stock exchange. This study further explores that there are financially distressed companies among sugar sector listed companies.

۲Cadmium Accumulation and Histological Lesion in Mosquitofish (Gambusia affinis) tissues Following Acute and Chronic Exposure
نویسنده(ها): ، ، ، ، ، ، ،
اطلاعات انتشار: International Journal Of Environmental Research، پنجم،شماره۳، Summer ۲۰۱۱، سال
تعداد صفحات: ۱۲
In this study, cadmium (Cd) accumulation was studied in an experimental aquatic exposure. Mosquitofish (Gambusia affinis) were acutely exposed for 96 h to a high concentration of Cd (12 mg\L) and were chronically exposed to a low concentration of Cd(0.4 mg\L) for 30 days. Cd accumulation profiles differed between the two Cd exposures. The Cd concentation in G. affinis tissues increased linearly during acute exposure. In contrast, chronic exposure presented a biphasic pattern of accumulation, with Cd accumulation increasing until 20 days post–exposure then decreasing by the 30th day of the experiment. Histopathological investigations revealed greater changes in gills, kidney and liver tissues after chronic exposure than those recorded during acute exposure. The changes in gill were characterized by epithelial lifting, total and partial lamellar fusion, epithelial necrosis as well as telangiectasis. Necrosis of epithelial cells of renal tubules, glomerular contraction and reduction of Bowman’s space were observed in the kidney tissue of exposed fish. The liver hepatocytes showed cytoplasmic vacuolization with lipid droplets and glycogen accumulation. Desquamation of hepatic tissue, congestion of the hepatic central vein and an increase in sinusoidal space were also observed. The result showed that, although Cd accumulation, following acute and chronic exposure, severely affects vital organs in mosquitofish; G. affinis adapts to continued metal accumulation. We hypothesise that this adaptation occurs through activation of a metal resistance mechanism.

۳Bioaccumulation of Heavy Metals in Fish Species Collected From Former Tin Mining Catchment
نویسنده(ها): ، ، ، ، ،
اطلاعات انتشار: International Journal Of Environmental Research، ششم،شماره۱، Winter ۲۰۱۲، سال
تعداد صفحات: ۱۰
This study has been carried out to determine the accumulation of heavy metals (arsenic, copper, lead, tin and zinc) in fish samples collected from former tin mining catchment. Total eight types of fish family having fifteen different species are identified. Cyperinidae is the most abundant family with eight different species found in the catchment. Fish samples were analysed by using inductively coupled plasma optical emission spectrophotometer ICP–OES. The accuracy of method is validated by certified reference material. The highest level of arsenic was observed in Hampala macrolepidota while Osteochilus hasselti shows the least. For Copper concentrations, the maximum was obtained in Mastacembelus armatus and the minimum in Oxyeleotris marmorata. High levels of lead, tin and zinc were found in the Rasbora elegans, Trichogaster trichopterus, Oxyeleotris marmorata respectively while Macrobrachium resenbergii,Mastacembelus armatus, Rasbora elegans had the least concentrations. The sequence of order of the heavy metals measured was Sn > Pb >Zn > Cu> As, respectively. The results showed elevated levels of tin, led and zinc in all the fish samples although copper and arsenic were available in relatively low concentration in the most samples. Sn, Pb, and Zn concentration in the samples were greater than Malaysia food act permissible levels. Hazard index 1 suggests unlikely adverse health effects whereas HI > 1 suggests the probability of adverse health effects. Although the heavy metals analysed in the catchment did not pose any immediate health risk to humans but due to the bioaccumulation and magnification of these heavy metals in humans, it is essential to safeguard levels of the metals in the environment.

۴Characterization of the Products Obtained in Coal Pyrolysis: A Case study of Some Pakistani Co
نویسنده(ها): ، ، ، ، ، ، ، ، ،
اطلاعات انتشار: Iranian Journal of Chemistry and Chemical Engineering (IJCCE)، سي ام،شماره۳(پياپي ۵۹)، ۲۰۱۱، سال
تعداد صفحات: ۴
Thermal decomposition of two coal samples obtained from Top Seam Sibi (TSS) and Sore Range Quetta (SRQ) coal fields in their raw and acid washed forms were carried out in an open type tubular pyrolyzer coupled to a gas chromatograph with FID. Elemental analyses were carried out with Scanning Electron Microscope–Energy Dispersive X–rays (SEM–EDX) analyzer. Effect of inherent mineral contents on the yields of pyrolysis products was investigated using acid washed coal samples. It was observed that total volatiles decreased as compared to raw form samples. Deductions in tar and liquid fractions were observed for both the acid washed Top Seam Sibi and Sore Range Quetta coals as compared to their raw forms where as an increase in the gas yield was noted in both the cases.

۵Development of Synergic Mixed Metal Oxides for the Combined Catalytic–Absorptive Removal of Nitric Oxide from Diesel Exhaust
نویسنده(ها): ، ، ، ، ،
اطلاعات انتشار: Iranian Journal of Chemistry and Chemical Engineering (IJCCE)، سي و دوم،شماره۱(پياپي ۶۵)، ۲۰۱۳، سال
تعداد صفحات: ۱۲
The NO removal over oxide sorbents (K2O\Al2O3 , CaO\Al2O3 and BaO\Al2O3) at a loading of up to 25 wt.% was investigated using a synthetic diesel exhaust gas containing 1,000 ppm NO, 1000 ppm iso–butane (i–C4H10), 8% O2 and N2 balance. The reactor was operated at 250 oC to 450 oC for the activity study. NO was effectively stored (removal efficiencies between 30–60 %) as nitrate under experimental conditions after surface oxidation to NO2; and the maximum removal efficiency decreased in the order of K2O\Al2O3 (55.4 %) > BaO\Al2O3 (39.0 %) > CaO\Al2O3 (37.0 %). K2O\Al2O3 had higher mobility; but loadings higher than 15 wt.% were detrimental to the morphological properties. Despite higher basicity, CaO\Al2O3 showed lower removal efficiency of NO compared to BaO(10)\Al2O3 due to low catalytic NO2 formation activity. Unlike K2O(10)\Al2O3, BaO(10)\Al2O3 showed increasing NO removal between 350 oC and 450 oC. K2O(5)BaO(5)\Al2O3 resulted in better surface area and volume leading to about 65 % of NO removal. This was attributed to synergic effects between physicochemical, catalytic and NO removal properties of the components. The high performance of K2O(5)BaO(5)\Al2O3 was successfully elucidated based on the characteristics of the sorbent.

۶AN EXPERIMENTAL INVESTIGATION OF THE SOUNDS OF SILENCE METAHEURISTIC FOR THE MULTI–MODE RESOURCE–CONSTRAINED PROJECT SCHEDULING WITH PRE–OPTIMIZED REPERTOIRE ON THE HARDEST MMLIB+ SET
نویسنده(ها): ، ، ،
اطلاعات انتشار: International Journal of Optimization in Civil Engineering، دوم،شماره۴، ۲۰۱۲، سال
تعداد صفحات: ۱۲
This paper presents an experimental investigation of the Sounds of Silence (SoS) harmony search metaheuristic for the multi–mode resource–constrained project scheduling problem (MRCPSP) using a pre–optimized starting repertoire. The presented algorithm is based on the time oriented version of the SoS harmony search metaheuristic developed by Csébfalvi et al. [1] for the single–mode resource–constrained project scheduling problem (RCPSP). The multi–mode SoS version exploits the fact that using a state–of–the art solver a small mixed integer linear programming problem (MILP) or a large linear programming problem (LP) can be solved within reasonable time. In order to illustrate the viability of the pre–optimized starting repertoire we present computational results for the hardest and largest MMLIB+ benchmark set developed by Van Peteghem and Vanhoucke [2]. The computational result reveals the fact, that the pre–optimized repertoire drastically increases the efficiency of the problem solvong process.

۷Patterns of flow evolution in the central area of the Romanian Plain, Case study: the Calnistea Catchment (Romania)
نویسنده(ها): ، ، ، ، ،
اطلاعات انتشار: Caspian Journal of Environmental Sciences، نهم،شماره۱، ۲۰۱۱، سال
تعداد صفحات: ۱۵
This paper seeks to emphasize the flow variability in the Calnistea catchment by analyzing the local physiographic factors. The research has shown that the amount of precipitation that falls to the ground is low, the rocks in the region are soft, but highly permeable, gradients are gentle in most of the territory and vegetal cover is sparse and therefore cannot hold important amounts of water. Under the circumstances, the flow is controlled especially by precipitation, gradient and rock permeability, which largely explainsthe rather low values of the drainage density, as well as the frequency with which the rivers dry up completely. The moisture deficit of the summer season is compensated to a certain extent by the existence of a chain of ponds along the main streams. The situation could further be improved if local authorities will find the necessary financial means in order to excavate artificial channels to bring water from the neighboring catchments. Although the flow values are generally low, under exceptional synoptic conditions the heavy rainfalls can lead to the formation of flash floods that can damage settlements,transportation routes and crops. Consequently, it is necessary to build protection levees in the lowlands and to regulate the stream flow.
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