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  • Author: Tanveer Hussain x
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Abstract

The aim of this study was to investigate the effect of knitting parameters on the moisture management and air permeability of the interlock fabrics. Samples were produced at two different knitting gauges, each with three different stitch lengths. It was found that the fabric mass per square metre increases by increasing machine gauge and decreasing the stitch length, whereas the fabric thickness and porosity increase at these settings. It was further concluded that the loosely knitted fabric samples with higher amount of entrapped air exhibit good air permeability but poor moisture management properties.

Because of the high content of inactive molybdenum in neutron irradiated MoO3, large columns containing alumina or gel are needed to produce chromatographic 99Mo→99mTc generator. This results in large elution volumes containing relatively high 99Mo breakthrough and low concentrations of 99mTcO4 -. The decrease in specific volume of 99mTc places a limitation on reconstitution of some kits for 99mTc radiopharmaceuticals applied in diagnostic nuclear medicine. Hence concentration technique is mandatory for effective utilization of (n,γ) produced 99Mo/99mTc generators at the start of its life whereas in case of fission 99Mo/99mTc generator the technique may be quite useful at the end of first week of its life. We report post elution concentration of 99mTc using in house prepared Pb column. The high bolus volumes (10–60 ml saline) can conveniently be concentrated in ∼1 ml of saline.

The high bolus volumes (20–40mL) of the generator-produced Rhenium-188 require post elution concentration of the eluate for the preparation of a dissolved β source and radiopharmaceuticals labeled with Re-188 for radiotherapy. Solvent extraction of 188Re in methyl ethyl ketone was studied. With the increase of organic phase volume, extraction of 188Re was enhanced while mixing time of aqueous and organic phases did not show any significant effect on the extractability of 188Re in the organic phase. Almost 80% of 188Re was extracted in methyl ethyl ketone at a volume ratio of 1:2 for aqueous and organic phases. By evaporation/distillation of methyl ethyl ketone, 188Re was concentrated and dissolved in the desired volume of physiological saline.

Abstract

Arsenic-77 (T 1/2=1.6 d) was produced by irradiating natural germanium in Pakistan Research Reactor-1. The nuclear reaction 76Ge(n,γ) produces 77Ge, which decays by emission of β- particles into 77As. The neutron irradiated target was dissolved in aqua regia, excess of acid was removed by evaporation and finally the solution in basic media was passed through hydrous zirconium oxide (HZO) column. The Ge was quantitatively retained on HZO, while 77As was present in the effluent. More than 90% 77As was recovered. The chemical impurity of Ge in 77As was <0.01 μg/mL.

Abstract

In view of promising efficiency of advanced oxidation process, ZnO/UV/H2O2 based advanced oxidation process (AOP) was employed for the degradation of Disperse Red-60 (DR-60) in aqueous medium. The process variables such as concentration of catalysts, reaction time, pH, dye initial concentration and H2O2 dose were evaluated for maximum degradation of dye. The maximum degradation of 97% was achieved at optimum conditions of H2O2 (0.9 mL/L), ZnO (0.6 g/L) at pH 9.0 in 60 min irradiation time. The analysis of treated dye solution revealed the complete degradation under the effect of ZnO/UV/H2O2 treatment. The water quality parameters were also studied of treated and un-treated dye solution and up to 79% COD and 60% BOD reductions were achieved when dye was treated with at optimum conditions. The dissolved oxygen increased up to 85.6% after UV/H2O2/ZnO treatment. The toxicity was also monitored using hemolytic and Ames tests and results revealed that toxicity (cytotoxicity and mutagenicity) was also reduced significantly. In view of promising efficiency of UV/H2O2/ZnO system, it could possibly be used for the treatment of wastewater containing toxic dyes.

Abstract

The double-diffusive tangent hyperbolic nanofluid containing motile gyrotactic microorganisms and magnetohydrodynamics past a stretching sheet is examined. By adopting the scaling group of transformation, the governing equations of motion are transformed into a system of nonlinear ordinary differential equations. The Keller box scheme, a finite difference method, has been employed for the solution of the nonlinear ordinary differential equations. The behaviour of the working fluid against various parameters of physical nature has been analyzed through graphs and tables. The behaviour of different physical quantities of interest such as heat transfer rate, density of the motile gyrotactic microorganisms and mass transfer rate is also discussed in the form of tables and graphs. It is found that the modified Dufour parameter has an increasing effect on the temperature profile. The solute profile is observed to decay as a result of an augmentation in the nanofluid Lewis number.

An introduction

Abstract

UV absorbers developed for finishing of textile materials play a significant role in protection against UV radiations but their discharge in wastewater during processing and laundry action also retain serious concern to living species due to their recalcitrant nature. The current study examined the mineralization and degradation of two vinylsulfone and nitrogen (N-) containing UV absorber compounds (1a, 2a) via two effective Fenton and UV/H2O2 oxidation. The results showed that both the Fenton and UV/H2O2 processes mineralized the synthesized UV absorbers effectively; however the mineralization process with Fenton oxidation was more effective than the UV/H2O2. The mineralization of synthesized UV absorbers was affected by process parameters (dosage of Fe2+ and H2O2 pH and reaction time). Under attained optimum conditions of Fenton oxidation, dose of Fe2+ (15 mg/L), H2O2 (500 mg/L), pH (3.0) and contact time (120 minutes), 75.43 and 77.54% of Chemical Oxygen Demand removal was achieved for 1a and 2a, respectively. Whereas, the optimum conditions of UV/H2O2 process were H2O2 (700 mg/L), pH(3.0) and irradiation time (200 minutes) that brought 54.33 and 57.65% COD removal in case of 1a and 2a, respectively. The results indicated that the Fenton oxidation can be successfully employed for the mineralization of triazine based UV absorbers.

Abstract

The aim of this research is to study the effect of clothing manufacturing parameters, that is, stitch type, stitch density, sewing thread type and washing type on the dimensional stability of single jersey knitted garment. Single jersey bleached fabric, made from Ne 32 cotton combed ring spun yarn, was used to make 32 medium size crew neck T-shirts selecting two levels of stitch type, stitch density, sewing thread type and wash type according to the experimental design. After constructing the garments, four critical measurements of each garment, that is, body length, body width, across shoulder and sleeve length were measured. The constructed garments were divided into two equal groups. One group was washed with water and the other group was washed using a detergent. After washing, drying and tumbling, the same critical measurements of each garment were taken and the percent shrinkage was calculated. Analysis of data was done on responses of output variables against the input variables using MINITAB. The results showed that three input variables: stitch type, stitch density and garment wash type have significant effect on all the output variables.