Birjand, Iran

Birjand University
Birjand, Iran

Birjand University of Medical science is a medical school in Iran.Located in Birjand of South Khorasan Province, the school was founded in 1985 under the supervision of Mashhad University of Medical science, but was separated later as an independent institute.The university is state operated, and currently trains 1,800 students in 13 departments in 5 Colleges of Nursing & Midwifery, Health science, Medicine, Para-clinical science and Dentistry as well as 3 satellite schools.The University operates two teaching hospitals and 10 clinics in the area. Wikipedia.

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Etedali S.,Birjand University
Bulletin of Earthquake Engineering | Year: 2017

In this paper, a new modified independent modal space control, namely independent modal space proportional-integral-derivative control (IMSPIDC), is proposed. The proposed control approach is developed through combining the well-known idea of proportional- integral- derivative control with the independent modal space control theory. IMSPIDC is applied to the problem of structural control under seismic excitation. A good trade-off between the conflicted modal structural responses and modal control force is crated using a multi-objective cuckoo search. Considering two different control devices includes: (1) an active tuned mass damper and (2) a system of active tendons, the performance of the proposed controller is evaluated in comparison with an independent modal space Linear–quadratic–Gaussian control (IMSLQRC). The Simulation results show that the IMSPIDC performs significantly better than the IMSLQRC in reduction of seismic responses of the structure. The proposed controller has several advantages in terms of simplicity and reduction of required sensors to the number of controlled stories. Furthermore, an evaluation of robustness against stiffness uncertainties indicates that the IMSPIDC gives a better performance than IMSLQRC in this term. © 2017 Springer Science+Business Media Dordrecht

Sadeghi S.,Birjand University | Jahani M.,Birjand University
Food Chemistry | Year: 2013

A molecularly imprinted polymer (MIP) for the selective solid phase extraction (SPE) of florfenicol (FF) was prepared using FF as template and 4-vinyl pyridine (4-VP) as functional monomer. For comparison, non-imprinted polymer (NIP) was synthesized in the absence of FF. The synthesized polymers were characterised by infrared spectroscopy (IR), scanning electron microscopy (SEM), thermogravimetry analysis (TGA) and differential thermal analysis (DTA). A molecularly imprinted solid phase extraction (MISPE) procedure was performed in column method by spectrophotometry detection technique. The prepared FF-MIP showed higher adsorption capacity than the non-imprinted polymer (NIP) and the maximum static adsorption capacities of FF on the MIP and the NIP were 4.32 and 2.88 mg g-1, respectively. Kinetics of the adsorption was fast and the adsorption equilibrium was achieved in 30 min. The accuracy of the developed method was satisfactory for determination of FF in fish, chicken meat and honey samples. © 2013 Elsevier Ltd.

The aim of this article was to optimize the mechanical alloying process for synthesizing of Al-8vol%SiC nanocomposite powders through an artificial neural network based on multiobjective optimization procedure. First, a suitable trained multi-layer perceptron (MLP) neural network was established for modeling purpose. Process variables as inputs of the network included milling time, milling speed, and balls to powders weight ratio. Parameters of the nanocomposite as outputs of the network were the crystallite size and the lattice strain of the aluminum matrix. The optimization was carried out by using two methods: gradient descent and pattern search. The aim of the optimization was to determine the minimum crystallite size and the maximum lattice strain of the aluminum matrix that could be obtained by regulating the mechanical alloying process variables. The response surfaces and the contour plots showed that the combination of the artificial neural network (ANN) and the optimization procedure were able to optimize the mechanical alloying process to synthesize Al-8vol%SiC nanocomposite. Copyright © 2012 Taylor and Francis Group, LLC.

A sensitive and selective method for the preconcentration and speciation of sub ng L -1 levels of chromium species in aqueous solutions with high salt contents is described. The developed method is based on temperature-controlled microextraction of chromium species using the 1-hexyl-3-methylimidazolium hexafluorophosphate ([HMIM][PF 6]) ionic liquid as an extractant followed by electrothermal atomic absorption spectrometry (ETAAS) determination. The extraction of chromium species from aqueous solution into the fine droplets of [HMIM][PF 6] was performed with ammonium pyrrolidine dithiocarbamate (APDC) as the chelating agent. Some predominant factors affecting the preconcentration and speciation of both Cr(III) and Cr(VI) species were evaluated and optimized. Under the optimum conditions, the calibration graphs were linear over the concentration ranges from 50 to 200 ng L -1 for Cr(III) and from 25 to 150 ng L -1 for Cr(VI). The limits of detection (LOD) of the developed method were 5.40 ng L -1 and 2.45 ng L -1 for Cr(III) and Cr(VI) ions, respectively. The enrichment factor for chromium species was found to be 42. The relative standard deviations for six replicate determinations of 100 ng L -1 of either Cr(VI) or Cr(III) were 4.24% and 3.05%, respectively. The developed method was successfully applied to the speciation and determination of chromium species in water and urine samples. © 2012 Elsevier B.V.

Sadeghi S.,Birjand University | Aboobakri E.,Birjand University
Microchimica Acta | Year: 2012

We have synthesized ferromagnetic nanoparticles with an imprinted polymer coating that is capable of adsorbing and extracting uranyl ions. The adsorbent was characterized using infrared spectroscopy, elemental analysis, X-ray powder diffraction analysis, and scanning electron microscopy. The effects of sample pH, sample volume, weight of the adsorbent, contact time and of other ions have been investigated in the batch extraction mode. The performance of the material was compared to that of particles coated with a non-imprinted polymer. The adsorbent containing the imprinted coating displays higher sorption capacity and better selectivity to uranyl ions. The method was successfully applied to the determination of uranyl ions in water samples. © 2012 Springer-Verlag.

The paper describes the study of the photocatalytic oxidation and antibacterial properties of cotton fabric treated with zinc oxide-silver (ZnO-Ag) nanocomposites. The ZnO nanoparticles were synthesized by an in situ approach on the surface of activated cotton fibers seeded with Ag nanoparticles. The effect of Ag nanoparticle-seeding and synthesis temperature on the morphological, thermal, photocatalytic and antibacterial properties of the ZnO-Ag nanocomposite-treated cotton fibers were characterized using scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffractometry, thermo gravimetric analysis, and Attenuated Total Reflection-Fourier Transform Infrared spectroscopy. Synthesizing ZnO nanoparticles on the surface of un-activated cotton fibers led to the formation of agglomerated nanoparticles while the Ag nanoparticle-seeded cotton fibers prevented this. The results indicated the presence of ZnO-Ag nanocomposites on the coated cotton fabrics, and all loaded samples presented an inhibition zone against S. aureus and E. coli bacteria. © the Partner Organisations 2014.

Nanofibrous hybrid yarns of polyvinyl alcohol (PVA) and poly-l-lactide acid (PLLA) with the antibacterial activity were prepared that contains 0, 5, 10, 20, and 30 wt.% of silver nanoparticles according to the PVA polymer content. This was performed by electrospinning using distilled water and 2, 2, 2-trifluoroethanol as a solvent for PVA and PLLA respectively, and sodium borohydride was used as a reducing agent. The scanning electron microscope observation confirmed the formation of AgNPs into the PVA nanofiber structure, and they were uniform, bead free, cylindrical and smooth. The diameter of hybrid yarns and their nanofiber component was decreased as the silver nitrate concentration in electrospinning solutions was increased. The differential scanning calorimetry results indicated that the silver nanoparticles can form interactions with polymer chains and decrease the melting enthalpy. The mechanical analysis showed a lower stress and strain at break of the AgNP-loaded nanofibrous hybrid yarns than the unloaded hybrid yarn. However, there wasn't a statistically significant difference between the strain at break of electrospun nanofibrous hybrid yarns. Moreover, the bactericidal efficiency of all loaded samples was over 99.99%. © 2014 Elsevier B.V.

Common lambsquarters, a summer annual weed, has occupied comparatively different ecogeographical regions around the globe. To investigate the extent to which germination and emergence traits have differentiated in two natural populations of common lambsquarters from different environments (Denmark as mesic and Iran as xeric population), experiments were conducted in the laboratory. Germination of both populations was stimulated by light. The greatest germination percentage of xeric and mesic populations occurred at 25/15 and 20/10 C, respectively. The xeric population showed significantly greater germinability at the lowest (15/5 C) and the highest (35/25 C) fluctuating temperature regimes. Germination of the xeric population was only slightly affected, and the mesic population was severely retarded at a salinity level of 20 desi siemens (DS) m-1. Greater than 42% of the xeric seeds germinated at 30 dS m-1 salinity, while the mesic germination almost ceased at this salinity level. Germination of seeds placed in distilled water after the 14-d salinity exposure treatments (recovery rates) was also greater for the xeric vs. mesic populations. Xeric populations showed more than 65% germination up to the osmotic potential of -0.4 MPa, while decreasing osmotic potential from 0 to -0.4 MPa caused an 80% reduction in mesic population germinability (9% germination). The greatest emergence of xeric (77%) and mesic (70%) populations occurred for seeds placed on the soil surface and no seedlings emerged from burial depth 3 cm. These study results suggest that common lambsquarters populations have differentiated for heat, salinity, and drought tolerance at germination stage. These contrasting germination patterns are appeared to be due to either adaptation via natural selection or maternal effects, or some combination of both. Though this study has certain limitations, it, through its findings and their propositions, adds to the existing knowledge about interpopulation differences in germination requirements of common lambsquarters, as a globally distributed species. © 2011 Weed Science Society of America.

Rakhshkhorshid M.,Birjand University
International Journal of Advanced Manufacturing Technology | Year: 2015

In this paper, a new simple model was developed based on a power function of Zener–Hollomon parameter and a third-order polynomial function of strainm (m is a constant) to model the hot flow stress of API X65 pipeline steel. The results of the developed equation for modeling the hot flow stress of API X65 pipeline steel was compared with two other constitutive equations, including the Arrhenius equation with strain-dependent constants and an equation with the peak stress, peak strain, and four constants. The performance of all three equations was compared with each other using a root-mean-square error (RMSE) criterion. According to the results obtained, the developed model showed better performance than that of the Arrhenius equation, but worse performance than that of the equation with the peak stress and peak strain. The simplicity of the proposed model is its advantage over the other considered constitutive equations. However, its performance is in an acceptable range. © 2014, Springer-Verlag London.

A new magnetically separable catalyst consisting of quinuclidin-3-thiol supported on propylsilane-functionalized silica-coated FeNi3 nanoparticles (FeNi3/quinuclidine) has been prepared. The synthesized catalyst was characterized by powder X-ray diffraction, transmission electron microscopy, vibrating sample magnetometry, thermogravimetric analysis, and Fourier transform infrared spectroscopy. The immobilized FeNi 3/quinuclidine was shown to be an efficient heterogeneous catalyst for the synthesis of triazolo[1,2-a]indazole-triones under solvent-free conditions at room temperature. The catalyst is readily recovered by simple magnetic decantation and can be recycled several times with no significant loss of catalytic activity. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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