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Matinfar M.,University of Mazandaran | Zareamoghaddam H.,Islamic Azad university at Kashmar | Eslami M.,University of Mazandaran | Saeidy M.,Islamic Azad University
Computers and Mathematics with Applications | Year: 2012

There are verities of useful Krylov subspace methods to solve nonsymmetric linear system of equations. GMRES is one of the best Krylov solvers with several different variants to solve large sparse linear systems. Any GMRES implementation has some advantages. As the solution of ill-posed problems are important. In this paper, some GMRES variants are discussed and applied to solve these kinds of problems. Residual smoothing techniques are efficient ways to accelerate the convergence speed of some iterative methods like CG variants. At the end of this paper, some residual smoothing techniques are applied for different GMRES methods to test the influence of these techniques on GMRES implementations. © 2011 Elsevier Ltd. All rights reserved.

Seyednour R.,University of Social Welfare and Rehabilitation Sciences | Chekaniazar V.,Islamic Azad university at Kashmar
Asian Journal of Animal and Veterinary Advances | Year: 2011

The aim of present study was to investigate the cellular phones emitted EMFs (Electromagnetic fields) effect on serum progesterone, cortisol and glucose concentration in exposed female hamsters. Seventy two female golden hamsters (mature and non-pregnant) were used. The animals were divided into three groups: group 1-the control group without any EMF exposure; group 2-the short-term EMF exposure (10 day, 3 h daily) and group 3-the long-term EMF exposure (60 day, 3 h daily). The 950 MHZ EMFs emitted by the antenna of cellular phones (Specify: ON, SAR: 0.60 week kg -1) was produced for short-or long-term (group 2 and 3), respectively. Exposing to 900 MHZ EMF caused decreases in progesterone (p<0.01) and increases in cortisol for both exposed groups (short-term and long-term) (p<0.01) in comparison with control group. Group exposed for 60 days had significantly higher blood glucose rate in comparison with control or short-term exposed groups. May, 950 MHZ EMFs caused stressful condition, cortisol releasing and subsequent hyper-glycemia in long-term exposing. Also, adrenal and reproductive glands may affect by 950 MHZ EMFs and caused changes in serum progesterone rate. It was concluded that short-or long-term exposure to 950 MHZ may cause progesterone suppressing and cortisol releasing but this frequency only in long-term exposure could cause hyper-glycemia in hamster as a laboratory model. © 2011 Academic Journals Inc.

Talebi R.,Islamic Azad University at Tehran | Safazade S.,Islamic Azad university at Kashmar
Journal of Materials Science: Materials in Electronics | Year: 2016

In the present study, for the first time lanthanum titanate (La2Ti2O7) nanoparticles were prepared via sol–gel auto-combustion method with the aid of lanthanum nitrate, tetra-n-butyl titanate and tyrosine. Tyrosine plays role as fuel, capping agent, and reductant in the synthesis of La2Ti2O7 nanoparticles. The formation of pure crystallized La2Ti2O7 nanocrystals occurred when the precursor was heat-treated at 700 °C in air for 150 min. The structural, morphological and optical properties of as-obtained products were characterized by techniques such as XRD, EDS, SEM, and UV–visible. The magnetic properties of as-prepared lanthanum titanate nanoparticles were also investigated with vibrating sample magnetometer. Furthermore, the photocatalytic properties of as-synthesized La2Ti2O7 were evaluated by degradation of methyl orange as water contaminant. © 2016 Springer Science+Business Media New York

Hosseini M.S.,Birjand University | Hosseini-Bandegharaei A.,Islamic Azad university at Kashmar
Journal of Radioanalytical and Nuclear Chemistry | Year: 2010

A new chelating polymeric sorbent as an extractant impregnated resin (EIR) has been developed using eosin B and Amberlite IRA-410 resin. The impregnation process was characterized by FT-IR spectroscopy. The eosin B-impregnated resin showed superior binding affinity for Th(IV) over U(VI) and many co-existing ions. The influence of various physicochemical parameters on the recovery of Th(IV) were optimized by both static and dynamic methods. The Langmuir adsorption isotherm gave a satisfactory fit of the equilibrium data. The kinetic studies performed for Th(IV) sorption revealed that <20 min was sufficient for reaching equilibrium metal ion sorption. A preconcentration factor of 100 was found for the column-mode extraction. The accuracy of the developed method in conjunction with Arsenazo III procedure was tested by analyzing geological reference materials and seawater sample, which are prepared, synthetically. Furthermore, the above procedure has been successfully employed for the analysis of natural water samples. © 2009 Akadémiai Kiadó, Budapest, Hungary.

Hosseini M.S.,Birjand University | Hosseini-Bandegharaei A.,Islamic Azad university at Kashmar
Journal of Hazardous Materials | Year: 2011

This paper reports the results obtained by studying the ion-exchange properties of a new solvent impregnated resin (SIR), which was prepared by impregnation of quinizarin (1,4-dihydroxyanthraquinone, QNZ) on Amberlite XAD-16 after nitration of the benzene rings present in its structure. The sorption behavior of Th(IV) and U(VI) on/in the modified SIR was compared with that of the SIR prepared via the conventional method. It was observed that sorption capacity and sorption rate of the modified SIR are significantly greater than the conventional one. The modified SIR was then applied to the extraction of Th(IV) and U(VI) ions at the presence of many co-existence metal ions. The results obtained denote on successful application of this new SIR to analysis of natural water samples spiked to Th(IV) and U(VI) ions. © 2011 Elsevier B.V.

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