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- Author or Editor: Muhammad Iqbal x
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Abstract
Technetium-99m is the short-lived daughter product of the parent molybdenum-99, which is mainly produced by the fission of uranium-235. Management of radioactive waste is an integral part of fission 99Mo production and has high priority during the planning, design, construction and operational phase of a molybdenum-99 production facility. Within the licensing procedure the strategy of waste management, including the route for the spent targets and long lived fission products has to be described and approved by the responsible authorities. Waste will be generated as solids, liquids, and gases, and will include material in the low, intermediate and even highly radioactive categories. Initial treatment of waste streams is usually required at the production site, prior to short or long term storage. This technology is established and generally available in countries with an existing nuclear industry, such as Pakistan. In some instances storage facilities may need to be constructed. On site, treatment of gaseous waste will be carried out in the production facility while off-site treatment will be performed for solids and liquid radioactive waste.
Introduction
Drought is one of the major abiotic stresses that drastically reduces crop yield throughout the world. Being precursor of glutathione biosynthesis and involvement in other metabolic processes, cysteine (Cys) has been shown to alter growth and development in plants. In this context, we investigated Cys-induced physicochemical alterations in oat (Avena sativa L. var. Scott and var. F-411) plants under drought stress.
Methods
There were two levels of drought stress, i.e., control (100% field capacity) and drought (50% field capacity) and three levels of foliar application of Cys, i.e., 0, 10, and 20 mM. Experimental design was completely randomized block design.
Results
Drought stress significantly decreased growth parameters, chlorophyll (Chl) contents, while increased leaf membrane permeability (MP), ascorbic acid (AsA), and activity of catalase (CAT) and peroxidase (POD) enzymes. Foliar application of varying Cys levels significantly increased root fresh weight, root length, photosynthetic pigments (chl. a and b), AsA contents in var. Scott, and shoot length, total free amino acids, total phenolics and free proline contents in var. F-411.
Discussion
Of the two oat varieties, var. Scott proved better in root fresh weight, root length, chl. a and b contents, and total phenolic contents, while var. F-411 was higher in the values of shoot length, MP (%), total free amino acids, and free proline contents. Thus, on the basis of strong root system, total phenolics, and more photosynthetic contents (chl. a and b contents), var. Scott could be grown under semi-arid environments than that of var. F-411.
Abstract
Polyurethane composites containing spherical and flake-shaped silver fillers of micrometer and nanometer sizes were prepared by reacting suspensions of the silver filler in tetraethylene glycol with Desmodur® HL BA. Both the thermal conductivity and the stability of the silver composites are increased in comparison with a reference polyurethane sample without filler. Unexpectedly, the largest increases in thermal conductivity and stability are observed for the spherical silver particles of micrometer size but not for the silver nanoparticles, which is reasoned with larger aggregates of silver particles and a higher degree of crystallinity in the sample containing micrometer-sized silver particles.
Abstract
In the under developed countries, the people of far-flung rural areas still depend to a large extent upon herbal medicines. At the foundation of usage of herbal medicine is the experience of thousands of years. The present paper deals with the characterisation of exotic fruits for essential and toxic elements. The samples include Morus nigra, Morus alba, Salvadora persica and Carissa opaca (from low and high altitude). Two standardizations of neutron activation analysis, that is, semi-absolute k 0-instrumental neutron activation analysis (k 0-INAA) and epithermal neutron activation analysis (ENAA) were employed for the quantification of elements. The analysis methodologies were validated by analyzing the IAEA-336 (lichen) and NIST-SRM-1572 (citrus leaves). Sixteen elements including Br, Ca, Cl, Co, Cr, Fe, I, K, Mg, Mn, Na, Rb, Sb, Sc Sr, and Zn were determined in all samples. Daily intakes of various elements from the samples were measured and compared with the dietary reference intakes. Additionally, principal component analysis was performed to extract information regarding samples and elements.
Abstract
The high performance liquid chromatographic (HPLC) method was developed for the combined estimation of sodium alginate and pectin in raft forming pharmaceuticals on C18 column ZORBAX ODS (1.5 cm × 4.6 mm, 5 μm) with UV detection at 378 nm. The assay condition comprised of phosphate buffer pH 7.4 and methanol 60:40% v/v at a flow rate of 1.25 mL/min. The separation of sodium alginate and pectin with good resolution and a retention time less than 8 min was attained. The method was linear over a range of 200–800 μg/mL of sodium alginate and pectin. The regression values obtained from linearity curve of sodium alginate and pectin were 0.9993 and 0.9991, respectively. The retention time of sodium alginate and pectin was 3.931 and 7.470 min, respectively. The percent recovery of sodium alginate and pectin ranged from 94.2–98.5% and 92.1–98.4% respectively. The limit of detection (LOD) and limit of quantification (LOQ) of sodium alginate were found to be 2.443 and 3.129 μg/mL and the LOD and LOQ of pectin were 3.126 and 3.785 μg/mL, respectively. The resolution of sodium alginate and pectin was found in the range of 1.03–1.89 and 1.10–1.91, respectively. This method has been successfully applied to analyze the concentrations of sodium alginate and pectin in raft forming drug delivery systems.