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Dehdashtian S.,Iran University of Science and Technology | Gholivand M.B.,Razi UniversityKermanshah | Shamsipur M.,Razi UniversityKermanshah | Karimi Z.,Payame Noor University
Sensors and Actuators, B: Chemical | Year: 2015

Abstract A novel, simple, selective and robust sensor has been developed for the electrochemical determination of metformin (MET) using anodic stripping voltammetry. The sensor was designed by incorporating of a nano sized mesoporous silica material functionalized by copper ion (SBA-15-Cu(II)) in the carbon paste electrode (CPE). The sensitivity of the sensor was improved by increasing the accumulation of MET on the surface of the electrode through complex with copper ions. The synthesized SBA-15-Cu(II) was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Under optimized conditions, the modified electrode exhibited a linear response over the MET concentration range of 0.1-65 μM, with a detection limit of 30 nM. Also, the applicability of the method to the direct assays of the pharmaceutical and biological fluid real samples was investigated. © 2015 Elsevier B.V.


Torkashvand M.,Razi UniversityKermanshah | Gholivand M.B.,Razi UniversityKermanshah | Malekzadeh G.,Islamic Azad UniversityKhuzestan
Sensors and Actuators, B: Chemical | Year: 2016

In this paper a new electrochemical sensor based on molecularly imprinted polymer immobilized on multiwall carbon nanotube surface was introduced for determination of ceftazidime. The sensor was constructed via synthesis of a molecularly imprinted polymer on glassy carbon electrode which has been modified with carboxyl-functionalized multiwall carbon nanotubes. Then, for increasing the sensitivity of the sensor, Ag dendrites (AgDs) nanobranch was deposited on polymer electrochemically. The resulting imprinted polymer-multiwall carbon nanotube composite showed high sensitivity, excellent stability and good specific recognition behavior towards template molecule. The morphology of AgDs/MIP/c-MWCNT/GCE was investigated by field emission scanning electron microscopy, cyclic voltammetry and electrochemical impedance spectroscopy in detail. Under the optimal experimental conditions, the current response of the imprinted sensor was linear to the concentration of ceftazidime in the range of 2-500 and 500-7000 nM, with the limit of detection of 0.55 nM (S/N = 3). The proposed sensor has also been examined for recognition of ceftazidime quantitatively, in complicated matrices real samples. © 2016 Elsevier B.V. All rights reserved.


Mousavi H.,Razi UniversityKermanshah | Bagheri M.,Shahid Beheshti University | Khodadadi J.,Razi UniversityKermanshah
Physica E: Low-Dimensional Systems and Nanostructures | Year: 2015

Abstract Using a two-band tight-binding Harrison model and Green's function technique, the influences of both localized σ and delocalized π electrons on the density of states, the Pauli paramagnetic susceptibility, and the heat capacity of a graphene sheet are investigated. We witness an extension in the bandwidth and an increase in the number of Van-Hove singularities as well. As a notable point, besides the magnetic nature which includes diamagnetism in graphene-based nanosystems, a paramagnetic behavior associated with the itinerant π electrons could be occurred. Further, we report a Schottky anomaly in the heat capacity. This study asserts that the contribution of both σ and π electrons play dominant roles in the mentioned physical quantities. © 2015 Elsevier B.V.


Karami J.,Razi UniversityKermanshah | Zalipoor S.,Razi UniversityKermanshah | Pourjavad M.,Mashhad University of Medical Sciences
Iranian Journal of Obstetrics, Gynecology and Infertility | Year: 2014

Introduction: Premenstrual syndrome includes physical, cognitive, and behavioral changes and is one of the most common disorders of reproductive age which causes disruption in women’s function. So, applying inexpensive and effective methods is necessary to relieve or improve the symptoms. This study was performed with the aim to assess the efficacy of emotional disclosure on premenstrual syndrome. Methods: This is a quasi-experimental, pretest-posttest study with case and control group which was performed on 30 girl student with premenstrual syndrome living in the dormitories of Kermanshah Razi University. The subject were randomly assigned into two experimental and control groups. The experimental group performed 4 to 5 half hour sessions of written emotional disclosure during two weeks and the control group with same amount performed writing about the issues with less emotional dimension. Then, posttest was performed in both groups. Data were analyzed by covariance test. PResults: According to the results of covariance test, written emotional disclosure significantly decreased total score of premenstrual syndrome in the experimental group than the control group in posttest (P<0.003). Conclusion: Emotional disclosure is effective in decreasing the symptoms of premenstrual syndrome. © 2015, Mashhad University of Medical Sciences. All rights reserved.


Eight different grasses collected from pastures of the Kermanshah province (Kermanshah, Iran), at mid-vegetative stage were used to study the relationships between their chemical compositions, kinetic parameters of in vitro gas production and rumen methane production. There was a positive correlation (r = 0.62, p < 0.05) between crude protein (CP) content of grasses and total gas production (A) at 96h incubation. Negative correlations were also observed between acid detergent fiber (ADF) content and total gas production (r = -0.60, p < 0.05). Amongst the nutrients, neutral detergent fiber (NDF) and ADF were positively correlated with methane concentration, (r = 0.75 and 0.77, p < 0.01). The methane reduction potential (MRP) was negative for Trachyspermum copticum indicating higher methane production than the control hay for this grass. The MRP of Chamaemelum nobile was more than 25%, indicating plants that reduce methane production more than 20 percent methane in comparison with control actually have ingredients to reduce methane. © 2015, Eduem - Editora da Universidade Estadual de Maringa. All rights reserved.


Rafiee E.,Razi UniversityKermanshah | Joshaghani M.,Razi UniversityKermanshah | Ghaderi-Shekhi Abadi P.,Razi UniversityKermanshah
RSC Advances | Year: 2015

High-quality and high-active one-dimensional (1-D) Fe3O4 nanostructures were synthesized via an external magnetic field (EMF) at the intensity range 0-526 μT in aqueous solution, without using any surfactant and organic solvent at room temperature. Characterization of the products was carried out using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction spectroscopy (XRD), Fourier transform infrared spectrophotometry (FT-IR), a laser particle size analyzer, surface area (Brunauer-Emmett-Teller, BET), and vibrating sample magnetometer (VSM). The results show that EMF at a critical adjusted intensity has a great influence on the structural features such as the morphology, particle size, surface pore size distribution, and magnetic properties of the Fe3O4 nanostructure. The morphology changed from peg-like network structures to needle-like cage structures by an exposure synthesis treatment with EMF at an intensity of 362 μT. The catalytic activity of two nanostructures prepared in the presence and absence of EMF were compared in a tricomponents reaction (TCR) for the synthesis of trisubstituted imidazoles under electromagnetic irradiation. The best results were obtained for the catalyst produced in the presence of EMF while the tricomponent reaction was carried out in the absence of EMF. This EMF condition was used for the preparation of a series of alkyl-, aryl-, and heteroaryl-substituted imidazoles from the corresponding benzoin and benzil in aqueous solution as green reaction conditions. It was found that the catalyst can be efficiently recycled and reused for several repeating cycles without significant loss of catalytic activity. © The Royal Society of Chemistry.


Rafiee E.,Razi UniversityKermanshah | Joshaghani M.,Razi UniversityKermanshah | Ghaderi-Shekhi Abadi P.,Razi UniversityKermanshah
RSC Advances | Year: 2015

High-quality and high-active one-dimensional (1-D) Fe3O4 nanostructures were synthesized via an external magnetic field (EMF) at the intensity range 0-526 μT in aqueous solution, without using any surfactant and organic solvent at room temperature. Characterization of the products was carried out using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction spectroscopy (XRD), Fourier transform infrared spectrophotometry (FT-IR), a laser particle size analyzer, surface area (Brunauer-Emmett-Teller, BET), and vibrating sample magnetometer (VSM). The results show that EMF at a critical adjusted intensity has a great influence on the structural features such as the morphology, particle size, surface pore size distribution, and magnetic properties of the Fe3O4 nanostructure. The morphology changed from peg-like network structures to needle-like cage structures by an exposure synthesis treatment with EMF at an intensity of 362 μT. The catalytic activity of two nanostructures prepared in the presence and absence of EMF were compared in a tricomponents reaction (TCR) for the synthesis of trisubstituted imidazoles under electromagnetic irradiation. The best results were obtained for the catalyst produced in the presence of EMF while the tricomponent reaction was carried out in the absence of EMF. This EMF condition was used for the preparation of a series of alkyl-, aryl-, and heteroaryl-substituted imidazoles from the corresponding benzoin and benzil in aqueous solution as green reaction conditions. It was found that the catalyst can be efficiently recycled and reused for several repeating cycles without significant loss of catalytic activity. This journal is © The Royal Society of Chemistry.


Gholivand M.-B.,Razi UniversityKermanshah | Akbari A.,Razi UniversityKermanshah
Materials Science and Engineering C | Year: 2016

Multi-walled carbon nanotube (MWCNTS) coated with poly p-aminobenzene sulfonic acid/β-cyclodextrin (p-ABSA/β-CD) film was used as an effective strategy for modification of the surface of glassy carbon electrode (GCE). Electrochemical study and determination of citalopram (CT) were investigated at the p (p-ABSA)/β-CD/MWCNT/GC using cyclic and differential pulse anodic stripping voltammetric techniques. The results indicate that the p (p-ABSA)/β-CD/MWCNT/GC significantly enhanced the oxidation peak current of CT. The modified electrode was characterized by electrochemical impedance spectroscopy (EIS), scanning electron microscopy(SEM) and cyclic voltammetry (CV).The fabricated electrochemical sensor exhibits a fast and reversible linear response toward CT within the concentration ranges of 90 nM-1 μM, 1-11 μM and 11-100 μM with correlation coefficients greater than 0.99 and detection limit of 44 nM. The resulting functionalized polymer film features interesting electrochemical properties such good recovery, reproducibility and selectivity toward CT. The applicability of the proposed sensor was tested by determination of CT in pharmaceutical combinations and human body fluids. © 2016 Elsevier B.V. All rights reserved.


Rafiee E.,Razi UniversityKermanshah | Kahrizi M.,Razi UniversityKermanshah
Journal of Molecular Liquids | Year: 2016

A simple and efficient protocol has been developed for the Heck coupling reaction catalyzed by a two component catalytic system composed of palladium deposited oleic acid coated-Fe3O4 nanoparticles (Fe3O4@OA-Pd) and thermo-regulated molybdovanadate-based ionic liquid salts (H5PMo10V2O40-IL, Mo10V2-IL) as a novel and recyclable catalytic system. In this system, low amounts of Mo10V2-ILs are used as an efficient co-catalyst, which reduce cost and increase efficiency in the Heck coupling reaction. These thermo-regulated co-catalysts are thermo-responsive, and could reversibly transform to precipitate with a decrease in temperature. In this study, the catalytic activities of various types of Mo10V2-IL including Mo10V2-(3-sulfonic acid) propylpyridine (Mo10V2-PyPS), Mo10V2-(4-sulfonic acid) butylpyridine (Mo10V2-PyBS), Mo10V2-(4-sulfonic acid) butyltrimethyl amine (Mo10V2-TMABS), Mo10V2-(4-sulfonic acid) butyltriethyl amine (Mo10V2-TEABS) and Mo10V2-(4-sulfonic acid) butyltributyl amine (Mo10V2-TBABS) were investigated in the Heck reaction. It was shown that all of the mentioned co-catalysts are efficient. It is apparent from cyclic voltammetric measurements that, these catalytic systems are electroactive and undergo reversible redox transitions between palladium nanoparticles and Mo10V2-IL species, also, it contains strong acid sites and mobile protons which can activate Ar-X and Pd-X bonds in oxidative addition and reductive elimination steps. As evidenced from mechanistic investigations, the electron transfer properties and Brönsted acidity of Mo10V2-ILs have been most pronounced upon application of the Fe3O4@OA-Pd and Mo10V2-IL system in the Heck coupling reaction. Fe3O4@OA-Pd and Mo10V2-PyPS exhibited excellent activities and the methodology is applicable to diverse substrates providing good to excellent yields of desired products. Moreover, this catalytic system was recycled for four consecutive cycles without any significant loss in activity. © 2016 Elsevier B.V. All rights reserved.


Beigvand S.D.,Razi UniversityKermanshah | Abdi H.,Razi UniversityKermanshah | La Scala M.,Polytechnic of Bari
Electric Power Systems Research | Year: 2016

This paper presents the application of a novel optimization algorithm, namely gravitational search algorithm (GSA) to solve the non-convex combined heat and power economic dispatch (CHPED) problems. The proposed approach is based on the gravitational law and the law of particles motion. The effectiveness of the suggested algorithm is tested on study-cases which include modeling of valve-point loading effect and transmission losses. Results of GSA-based CHPED problem in terms of quality solution and computational performance are compared with various algorithms to show the ability of the introduced algorithm in finding an operating point with lower fuel cost. © 2015 Elsevier B.V. All rights reserved.

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