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Basseri G.,Islamic Azad University at Darab | Mehrabi Mazidi M.,Sahand University of Technology | Hosseini F.,Islamic Azad University at Shiraz | Razavi Aghjeh M.K.,Sahand University of Technology
Polymer Bulletin | Year: 2014

Morphological, rheological and mechanical properties of the polypropylene (PP) and poly(styrene-co-acrylonitrile) (SAN) blend containing poly(styrene-b-butadiene-b-styrene) (SBS) triblock copolymer (ranging from 0 to 20 wt%) were studied by scanning electron microscopy (SEM), small amplitude oscillatory shear analysis, and both tensile and impact tests, respectively. SEM observations showed that SBS reduced the diameter of the SAN dispersed particles as well as improved the adhesion between the matrix and the dispersed phase. Close examination of SEM micrographs further revealed that the dispersed phase domains were complex aggregates of SAN particles enveloped and joined together with the SBS compatibilizer in the PP matrix. The variation of the dynamic rheological parameters, including dynamic moduli (G and G″), complex viscosity (η-), loss factor (tan δ), together with Cole-Cole diagrams, with blend composition particularly at low frequency regions were determined to evaluate the interfacial activity of SBS copolymer. A specific viscoelastic phenomenon, i.e., "the second plateau", appeared at low frequencies for PP/SAN blend containing 20 wt% of SBS and exhibited a certain dependence on the SBS amount and dispersion state in the matrix. This phenomenon was attributed to the formation of aggregate structure between SAN particles and SBS triblock copolymer. Finally, the results of uniaxial tensile and Charpy impact tests conducted on both unnotched and notched specimens indicated that in PP/SAN blend, SBS functions as both compatibilizer and toughening agent. © 2013 Springer-Verlag Berlin Heidelberg. Source

Sohrabi M.R.,Islamic Azad University at North Tehran | Matbouie Z.,Islamic Azad University at Darab | Asgharinezhad A.A.,Shahid Beheshti University | Dehghani A.,Iran University of Science and Technology
Microchimica Acta | Year: 2013

We describe a novel magnetic metal-organic framework (MOF) for the preconcentration of Cd(II) and Pb(II) ions. The MOF was prepared from the Fe3O4-pyridine conjugate and the copper(II) complex of trimesic acid. The MOF was characterized by IR spectroscopy, elemental analysis, SEM and XRD. A Box-Behnken design through response surface methodology and experimental design was used to identify the optimal parameters for preconcentration. Extraction time, amount of magnetic MOF and pH value were found to be critical factors for uptake, while type, volume, concentration of eluent, and elution time are critical in the elution step. The ions were then determined by FAAS. The limits of detection are 0.2 and 1.1 μg L-1 for Cd(II), and Pb(II) ions, respectively, relative standard deviations are <4.5% (for five replicates at 50 μg L-1 of Cd(II) and Pb(II) ions), and the enrichment capacity of the MOF is at around 190 mg g-1 for both ions which is higher than the conventional Fe3O4-pyridine material. The magnetic MOF was successfully applied to the rapid extraction of trace quantities of Cd(II) and Pb(II) ions in fish, sediment, and water samples. © 2013 Springer-Verlag Wien. Source

Hajian R.,Islamic Azad University at Gachsaran | Ekhlasi E.,Islamic Azad University at Gachsaran | Daneshvar R.,Islamic Azad University at Darab
E-Journal of Chemistry | Year: 2012

The interactions between epirubicin (EPR) and double stranded DNA (ds-DNA) have been studied by UV-Vis spectrophotometry, cyclic voltammetry, fluorescence spectroscopy and viscometery. The apparent binding constant of epirubicin with DNA was found to be 3.8 × 10 5 mol -1 L and was studied at different temperatures. It indicated that the former method could be successfully applied to the determination of epirubicin. Also, the voltammetric behavior of EPR was investigated at glassy carbon electrode using cyclic voltammetry. Thermodynamic parameters including δH 0, δG 0 and δS 0 were determined as -5.7×10 4, -3.13×10 4 J mol -1 and -87.96 J mol -1 K -1 respectively. One indication of the strong interaction between DNA and EP was increasing of viscosity. The diffusion coefficients of EP in the absence (D 0) f and presence of ds-DNA (D o) b was calculated as 5.04×10 -6 and 1.13×10 -6 Cm 2 s -1 respectively. According to the thermodynamic parameters, the main binding force could be judged. The experimental results revealed that EPR and ds-DNA had strong interactions. The mechanism of quenching belonged to static quenching and the main sort of binding force was intercalation. Source

Khorsandi F.,Islamic Azad University at Darab | Yazdi F.A.,Yazd Agriculture and Natural Resources Research Center
Communications in Soil Science and Plant Analysis | Year: 2011

Texture and salt type influence the relationships between saturated paste electrical conductivity (ECe) and EC of other soil/water ratios. The objectives of this study were to develop and validate relationships between ECe and EC1:5 suspension for soils in Yazd Province and evaluate the effects of soil texture and gypsum on those relationships. Three hundred twenty-two soil samples were collected, of which 272 (all data) were used to develop the models and 50 were used to validate them. The soils were divided into two general textural categories of coarse and fine and two categories of with (G) and without gypsum (NG). Gypsum content had a stronger impact on the accuracy of the suspension method in predicting ECe than texture. The ECe = 5.60 EC1:5 - 4.37 and ECe = 5.37 EC1:5 + 0.57 models are recommended for soils with and without gypsum, respectively. The methodology can be implemented in other regions, particularly if gypsum is present. © Taylor & Francis Group, LLC. Source

Johari H.,Islamic Azad University at Darab
Journal of Kerman University of Medical Sciences | Year: 2013

Background & Aims: There are several reports about anti-oxidant effects of garlic in the literature. In this study the effect of garlic alcoholic-water extract on the treatment of lead-induced toxicity in kidney of neonatal rat and the protective effect of garlic alcoholic water extract on body and kidney weight and also kidney tissue were investigated. Method: Neonatal rats were divided into 7 groups, (n=8). The first group (control) received no material, the second group (sham) received 0.1 ml normal salin, the third group received 0.6 g/l lead, the forth group received 0.4 g/kg garlic alcoholic - water extract in water and alcohol solution (each 50%) and the fifth, sixth and seventh groups first received 0.6 g/l lead and then respectively 0.1, 0.2, 0.4, g/kg garlic. All substances were administered through gavage and in 10 consecutive days. Twenty four hours after the last day of injection, body and kidney weights were measured and after mild anesthesia, kidney was removed and fixed in formalin for preparing tissue sections. Tissue alterations were investigated by light microscope. Results: Based on the obtained results, body and kidney weights in the 3rd, 5th, 6th and 7th groups showed significant Increase as compared with the control group. Body and kidney weight in the 4th group showed significant decrease as compared with lead group. Histological examination of kidney tissue showed that garlic administration decreased the rate of kidney tissue damage. Conclusion: Garlic, due to its antioxidant effect, can prevent lead-induced toxicity and tissue damage in the kidney. Source

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