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Talebian N.,Islamic Azad University at Shahreza | Kheiri M.,Islamic Azad University at Falavarjan
Solid State Sciences | Year: 2014

Nickel oxide films were deposited onto glass substrates by sol-gel dip coating method using solvents of different polarities without any catalysts, templates or surfactants. Methanol, 1,4-butanediol, ethanol, and 2-propanol were used as solvents. The structural, optical and electrical properties of NiO films were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-visible spectroscopy and Hall effect measurements, respectively. Nickel oxide thin films with cubic phase crystal structure of various preferred orientations were obtained in the different solvents. The XRD results showed that films deposited from solution using higher polar solvents develop a (1 1 1) preferred orientation, while the (2 0 0)-orientated films were obtained using lower polar solvents. The average particle size increases with viscosity of solvents. Surface morphology of the nickel oxide film consisted of nanoparticles with uniform coverage of the substrate surface. The solvent of higher viscosity induced larger particle size. Band gap narrowing from 4.42 to 3.87 eV was observed using different solvents. The lower resistivity and Hall coefficient was obtained for prepared NiO films using higher polar solvents. The relationships between solvent physicochemical properties, preferred orientation, structural, optical and electrical properties of NiO films were investigated. © 2013 Elsevier Ltd. All rights reserved.

Fouladgar M.,Islamic Azad University at Falavarjan
International Journal of Electrochemical Science | Year: 2011

A new sensitive and selective electrochemical sensor was developed for determination of captopril (CAP) in tablet and human patient urine. Captopril is an inhibitor of the angiotensin-converting enzyme and is widely used for the treatment of hypertension and congestive heart failure. A voltammetric study of captopril has been carried out at the surface of carbon paste electrode modified with multi-wall carbon nanotubes as a sensor and ferrocene as a mediator. The electrochemical oxidation of captopril was investigated by chronoamperometry, cyclic and differential pulse voltammetric techniques. The dependence of peak currents on pH, concentration and the potential scan rate was investigated. Two linear dynamic ranges of 0.5-12 μM and 12-300 μM with a detection limit of 0.15 μM was obtained in phosphate buffer of pH = 9. Differential pulse voltammetry as a simple, rapid, sensitive and selective method was developed for the determination of captopril in tablet and human urine without any treatments. © 2011 by ESG.

Talebian N.,Islamic Azad University at Shahreza | Amininezhad S.M.,Islamic Azad University at Shahreza | Doudi M.,Islamic Azad University at Falavarjan
Journal of Photochemistry and Photobiology B: Biology | Year: 2013

ZnO materials with different morphologies have been synthesized via a simple solvothermal method using different solvents without any catalysts, templates or surfactants. The ZnO samples are employed in the inactivation of gram-negative Escherichia coli and gram-positive Staphylococcus aureus in MilliQ water. The photocatalytic activities of samples to degrade an azo dye, Acid Orange 74 (CI 18745), were also tested. XRD data showed that single-phase ZnO with the wurtzite crystal structure but different growth habits were obtained in the different solvents. SEM imaging illustrated that ZnO with flower-like, rod-like, and spherical shape were produced when water, 1-hexanol, and ethylene glycol were used as the solvent, respectively. The optical properties of the as-prepared ZnO materials were investigated by UV-vis absorption and photoluminescence spectra. The antibacterial efficiencies were affected by the physiological status of the bacterial cells, different morphologies and crystal growth habits, particle size and optical properties of ZnO samples. Results indicate that ZnO flower-like showed significantly higher photocatalytic inactivation than ZnO rod- and sphere-like against E. coli compared with S. aureus. It was found that the antibacterial activity of ZnO increased with decreasing crystallite size. The inactivation efficiencies for both organisms under light conditions were higher than under dark conditions. The obtained results were discussed according to the morphologies, optical and structural properties of ZnO powders as key parameters in photocatalytic and antibacterial activity. © 2013 Elsevier B.V. All rights reserved.

Momtaz H.,Islamic Azad University | Yadollahi S.,Islamic Azad University at Falavarjan
Diagnostic Pathology | Year: 2013

Background: Among all species of Listeria, Listeria monocytogenes (L. monocytogenes) is a major pathogenic microorganism of humans and animals and L. ivanovii is rarely pathogenic for humans. The objective of this study was to isolate and characterize Listeria species and to determine the frequencies of virulence genes in L. monocytogenes serotypes in fresh fish, shrimp, crab and lobster in Isfahan and Shahrekord, Iran. Methods: From September 2010 to April 2011, a total of 300 marine food samples were purchased from supermarkets of Isfahan and Shahrekord cities, Iran. All samples were cultured and the positive samples for L. monocytogenes were analyzed for presence of serotypes and virulence genes. Results: From the total 300 samples, 23 (10.45%) fresh fish and 1 (2.5%) shrimp samples were positive for Listeria spp., but there were no positive lobster and crab samples for Listeria species. Only L. monocytogenes was isolated from 17 fish (7.25%) and 1 shrimp (2.5%) samples while L. innocua, L. ivanovii and L. seeligeri only detected in fish samples (2 (0.9%), 3 (1.36%) and 1 (0.45%)), respectively. The plcA, prfA, actA, hlyA and iap virulence genes were detected in all of the 18 L. monocytogenes isolates. Totally, the 4b, 1/2a and 1/2b serotypes were detected in 66.66%, 5.55% and 27.77% bacterial isolates, respectively. Conclusions: Consumption of these sea foods, either raw or undercooked, may contribute to food-borne illness due to L. monocytogenes in Iran. The hygienic quality of sea food products should be observe.Virtual slides: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/3422944359800606. © 2013 Momtaz and Yadollahi; licensee BioMed Central Ltd.

Fouladgar M.,Islamic Azad University at Falavarjan
Measurement: Journal of the International Measurement Confederation | Year: 2016

In this work, ZnO nano particles were synthesized and their characteristics were investigated by scanning electron microscopy and X-ray powder diffraction. ZnO nano particles and a synthesized ionic liquid (1-Methyl-3-butylimidazolium bromide) were applied to modification of carbon paste electrode. Electrochemical behavior of benserazide (BA) was studied at modified electrode. Under optimum pH of 6.0, the relation between oxidation current and concentration of BA was linear in the range of 0.1-430.0 μmol L-1 BA. Detection limit of method was calculated to be 0.06 μmol L-1 BA. Effects of potential interferences on determination of BA were investigated and proposed method was used for determination of BA in biological samples. © 2016 Elsevier Ltd. All rights reserved.

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