Shaukat Ali Shahid

Improvement in the Water Retention Characteristics of Sandy Loam Soil Using a Newly Synthesized Poly(acrylamide-co-acrylic Acid)/AlZnFe2O4 Superabsorbent Hydrogel Nanocomposite Material

The use of some novel and efficient crop nutrient-based superabsorbent hydrogel nanocomposites (SHNCs), is currently becoming increasingly important to improve the crop yield and productivity, due to their water retention properties. In the present study a poly(Acrylamide-co-acrylic acid)/AlZnFe2O4 superabsorbent hydrogel nanocomposite was synthesized and its physical properties characterized using Energy Dispersive X-ray (EDX), FE-SEM and FTIR spectroscopic techniques. The effects of different levels of SHNC were studied to evaluate the moisture retention properties of sandy loam soil (sand 59%, silt 21%, clay 19%, pH 7.4, EC 1.92 dS/m). The soil amendment with 0.1, 0.2, 0.3 and 0.4 w/w% of SHNC enhanced the moisture retention significantly at field capacity compared to the untreated soil. Besides, in a separate experiment, seed germination and seedling growth of wheat was found to be notably improved with the application of SHNC. A delay in wilting of seedlings by 5–8 days was observed for SHNC-amended soil, thereby improving wheat plant growth and establishment.

Green Synthesis of Silver Nanoparticles: Structural Features and In Vivo and In Vitro Therapeutic Effects against Helicobacter pylori Induced Gastritis

This study evaluates in vivo and in vitro anti-Helicobacter pylori (H. pylori) efficacy of silver nanoparticles (Ag-NPs) prepared via a cost-effective green chemistry route wherein Peganum harmala L. seeds extract was used as a reducing and capping agent. The structural features, as elucidated by surface plasmon resonance spectrophotometry, transmission electron microscopy, and powder X-ray diffraction spectroscopy, revealed the Ag-NPs synthesized to be polydispersed in nature and spherical in shape with 5–40 nm size. A typical Ag-NPs suspension (S5), with size being 15 nm, when tested in vitro against forty-two local isolates and two reference strains, showed a considerable anti-H. pylori activity. In case of in vivo trial against H. pylori induced gastritis, after oral administration of 16 mg/kg body weight of S5 for seven days, a complete clearance was recorded in male albino rates. In comparative time-killing kinetics, S5 exhibited dose- and time-dependent anti-H. pylori activity that was almost similar to tetracycline and clarithromycin, less than amoxicillin, but higher than metronidazole. Furthermore, S5 was found to be an equally effective anti-H. pylori agent at low (≤4) and high pH with no drug resistance observed even up to 10 repeated exposures while a significant drug resistance was recorded for most of the standard drugs employed. The present results revealed the potential of the synthesized Ag-NPs as safer bactericidal agents for the treatment of H. pylori induced gastritis.

Effects of a Novel Poly (AA-co-AAm)/AlZnFe2O4/potassium Humate Superabsorbent Hydrogel Nanocomposite on Water Retention of Sandy Loam Soil and Wheat Seedling Growth

A novel poly(acrylic acid-co-acrylamide)AlZnFe2O4/potassium humate superabsorbent hydrogel nanocomposite (PHNC) was synthesized and its physical properties characterized using SEM, Energy Dispersive X-ray (EDX) and FTIR spectroscopic techniques. Air dried sandy loam soil was amended with 0.1 to 0.4 w/w% of PHNC to evaluate its soil moisture retention attributes. Effect of PHNC amendment on pH, electrical conductivity (EC), porosity, bulk density and hydraulic conductivity of sandy loam soil was also studied. The soil amendment with 0.1 to 0.4 w/w% of PHNC remarkably enhanced the moisture retention at field capacity as compared to the un-amended soils. Seed germination and seedling growth of wheat (Triticum aestivum L.) was considerably increased and a delay by 6–9 days in wilting of seedlings was observed in the soil amended with PHNC, resulting in improved wheat plant establishment and growth.

Soft tissue and water substitutes for megavoltage photon beams: An EGSnrc-based evaluation.

In this work, soft‐tissue equivalence of water, polystyrene, PMMA and water equivalence of polystyrene, and PMMA has been assessed for multiple megavoltage photon beams and field sizes. EGSnrc based Monte Carlo (MC) codes, BEAMnrc and DOSXYZnrc are used for the linac head modeling and the phantom dose calculations, respectively. Percentage depth doses (PDDs) are scored for two field sizes (5×5 cm2, 10×10 cm2) and photon energies (6 MV and 10 MV) in water, polystyrene, PMMA, and soft tissue. The comparisons of PDDs show that soft‐tissue equivalence of various materials varies with the depth in the phantom, field size, and photon energy. Water and PMMA are found to be the closest soft‐tissue and water substitutes, respectively. Soft‐tissue and water equivalence of dosimetry materials need to be evaluated for a range of photon energies and field sizes before their application in complex radiation beams. PACS numbers: 87.55.Gh, 87.55.K‐In this work, soft-tissue equivalence of water, polystyrene, PMMA and water equivalence of polystyrene, and PMMA has been assessed for multiple megavoltage photon beams and field sizes. EGSnrc based Monte Carlo (MC) codes, BEAMnrc and DOSXYZnrc are used for the linac head modeling and the phantom dose calculations, respectively. Percentage depth doses (PDDs) are scored for two field sizes (5×5 cm2, 10×10 cm2) and photon energies (6 MV and 10 MV) in water, polystyrene, PMMA, and soft tissue. The comparisons of PDDs show that soft-tissue equivalence of various materials varies with the depth in the phantom, field size, and photon energy. Water and PMMA are found to be the closest soft-tissue and water substitutes, respectively. Soft-tissue and water equivalence of dosimetry materials need to be evaluated for a range of photon energies and field sizes before their application in complex radiation beams. PACS numbers: 87.55.Gh, 87.55.K.

Characterization of newly synthesized ZrFe 2 O 5 nanomaterial and investigations of its tremendous photocatalytic properties under visible light irradiation

High functional ZrFe2O5 nanoparticles were synthesized using coprecipitation technique. The chemical composition of nanomaterials was studied by energy-dispersive X-ray (EDX). To observe the morphology, field emission scanning electron microscopy (FE-SEM) was used. X-ray diffraction (XRD) technique was utilized to appraise the structure of the synthesized material. The photocatalytic behavior of ZrFe2O5 nano-particles was investigated by measuring the degradation rate of toluidine blue O (TBO) dye in aqueous solution in the presence of ZrFe2O5 nano-particles under visible light irradiation. A steady decrease in absorption peak under visible light irradiation was observed by increasing exposure time. The degradation efficiency was observed as 92% after 140 min of exposure to visible light. Besides, ZrFe2O5 nanophotocatalyst could be recovered and recycled easily. The rate of TBO and total organic carbon (TOC) removal under visible light irradiation decreased by only 5% and 10%, respectively, after seven cycles of use, demonstrating the high photostability of the synthesized nano-photocatalyst material.

Sorption of Lead Ions from Aqueous Solution by Chickpea Leaves, Stems and Fruit Peelings

Leaves, stems and fruit peelings of chickpea (Cicer arientinum L.) were successfully utilized for the accumulation of lead ions from aqueous solutions onto their surfaces. The rate and extent of accumulation were affected by pH, particle size, contact time and the initial concentration of Pb(II) ions, respectively. The sorption capacities of leaves, stems and fruit peelings towards Pb(II) ions were found to be 81.30, 80.10 and 53.26%, respectively, at an initial Pb(II) ion concentration of 200 mg/dm3, optimum pH conditions of 6.0, a particle size of 0.354 mm and a contact time of 120 min. Most of the sorption occurred within the first 15 min and attained a maximum value after 120 min. The Bangham equation was used to express the adsorption mechanism. The adsorption rates of Pb(II) ions were found to decrease in the order: leaves > stems > fruit peelings. Possible cell–metal ion interactions may be due to the involvement of –COOH, –OH and –NH groups in the sorption process. The obtained sorption data were well fitted by the Freundlich and Langmuir adsorption isotherms, respectively. The results showed that chickpea leaves and stems behave as good adsorbents for the removal of Pb(II) ions from aqueous solution.

Laser-Assisted synthesis of Mn 0.50 Zn 0.50 Fe 2 O 4 nanomaterial: characterization and in vitro inhibition activity towards bacillus subtilis biofilm

There is growing interest in the development of novel nanomaterials with potential antimicrobial activity and lesser toxicity. In the current research work, Mn0.5Zn0.5Fe2O4 nanoparticles were synthesized via a novel coprecipitation cum laser ablation technique yielding fine spinal structured material. The synthesized nanomaterial was structurally characterized by X-ray diffraction technique which confirmed the formation and the crystalline nature of Mn0.50Zn0.50Fe2O4 nanomaterial. The crystallite size determined by Debye-Scherrers formula was found to be ∼12 nm. The formation of nanoparticles was evidenced by scanning electron microscopy. Energy dispersive X-ray analysis (EDXA) was performed for elemental analysis. The synthesized nanomaterial was interestingly found to be an effective antimicrobial agent and inhibited the growth of Bacillus subtilis biofilm formation. The 5 µg of Mn0.5Zn0.5Fe2O4 nanomaterial dissolved in 1mL of DMSO showed excellent biofilm inhibitory activity 91.23% ± 1.87 against Bacillus subtilis.

Synergistic Effect of Thiourea and Surfactants on Corrosion Inhibition of Stainless Steel-410 in Presence of Sulfuric Acid

The inhibition of corrosion of stainless steel (SS)-410 in sulfuric acid using thiourea and three different surfactants, cetyle trimethyl ammonium bromide (CTAB), sodium dodecyl sulfate (SDS) and X-Triton was studied. Corrosion rates were determined by using corrosion coupons. The corrosion rate was found to be decreased with increase in inhibitor concentration. It was observed that the maximum corrosion inhibition occurred in the post micellar concentration of the surfactants. By optimizing the corrosion inhibition performance of different blends of surfactants and thiourea in 3 M H2SO4, the corrosion inhibition order was found as: Triton X-100 + thiourea > CTAB + thiourea > SDS + thiourea. The best results obtained by the addition of 200 ppm thiourea in 500 ppm of Triton X-100 in 3 M H2SO4 acid solution. This blend decreased the corrosion rate of SS-410 to 657.66 mpy.

The Synergistic Effect of Thiourea and Surfactants on Corrosion Inhibition of Stainless Steel-316 in Hydrochloric Acid

Corrosion and scaling are the common problems to all the industries. A remedy of these problems was sought out through chemical treatment: indigenously available raw materials including thiourea, surfactants (cationic, anionic and nonionic containing pre, critical and post micellar concentration). Evaluation of corrosion inhibition properties stainless steel 316 by thiourea based inhibitor and its synergistic effect with cationic cetyl tri-methyl ammonium bromide (CTAB), anionic sodium dodecyl sulphate (SDS) and nonionic triton X-100 have been carried out by weight loss method as a function of concentration of thiourea and surfactants. These materials were applied to the coupons of stainless steel 316 in different acidic concentration. Corrosion rates were calculated using weight loss method. Excellent results were achieved regarding corrosion inhibition in the presence of thiourea and surfactants assuring the better performance of these chemicals. The results showed that corrosion rate was decreased from 90 mpy to 12.1 mpy after 720 hours by the addition of 200ppm thiourea in critical micellar concentration of SDS in 3M HCl acid solution.