AREFIFARD S.,Lorestan University
Geological Magazine | Year: 2017
The Capitanian to Wuchiapingian deposits in Zagros (southwest Iran), Alborz (North Iran) and Central Iran display important information about the end-Guadalupian extinction. According to lithological characteristics in the studied sections, the Guadalupian–Lopingian boundary (G-LB) interval can be subdivided into three units: the Capitanian unit, the latest Capitanian unit or interval unit (i.e. deposits in the topmost portion of the Capitanian strata) and the Wuchiapingian unit. The G-LB horizon is set at the base of Wuchiapingian deposits based on the first appearance datum (FAD) of the Late Permian diagnostic small foraminifers. The Capitanian unit was deposited subtidally, but the latest Capitanian unit was in the intertidal zone. The Wuchiapingian unit shows the return of subtidal conditions. A remarkable subaerial exposure occurs at the top of the Ruteh Formation, in Alborz, which is a laterite/bauxite horizon followed by continental deposits. The overall facies change in the G-L boundary intervals in the sections under study indicates a sea level drop around the G-LB which was at its lowest level in the Ruteh section. The decline and elimination of shallow marine biota in the G-LB interval took place in two steps in the Zagros and Alborz sections and in one step in Central Iran. These are indicative of the appearance of the stressful environment during the late Capitanian shallowing trend before the G-LB. The sea level drop and regression in the late Capitanian can be considered the major causes of end-Guadalupian extinction in the Iranian sections, but in the Alborz area volcanic activity is another feasible cause of this crisis. Copyright © Cambridge University Press 2017
Haghiabi A.H.,Lorestan University
Marine Pollution Bulletin | Year: 2017
Rivers are one of the main sources of water supply for agricultural, industrial, and urban use, and therefore, surveying their water quality is necessary. Recently, artificial neural networks have been proposed as a powerful tool for modeling and predicting water quality parameters in natural streams. In this paper, a multilayer neural network (MLP) model was developed to predict water quality parameters of Tireh River located in South West of Iran. The main parameters of water quality, namely total dissolved solids; specific conductivity; pH; and HCO3, Cl, Na, SO4, Mg, and Ca concentrations, were measured and predicted using the MLP model. The architecture of the proposed MLP model included two hidden layers, i.e., first and second hidden layers, in which eight and six neurons were considered, respectively. The tangent sigmoid and pure line functions were selected as transfer functions for the neurons in the hidden and output layers, respectively. Results showed that the MLP model performed suitably to predict water quality parameters of Tireh River. To assess the performance of the MLP model for water quality prediction along the studied area, in addition to the existing sampling stations, another 14 stations were considered. Evaluation of the performance of the developed MLP model to map the relationship between the water quality parameters along the studied area showed that the MLP model has suitable accuracy, and the minimum correlation between the results of the MLP model and the measured data was 0.85. © 2017.
Adeli M.,Lorestan University |
Adeli M.,Sharif University of Technology |
Soleyman R.,Research Institute of Petroleum Industry RIPI |
Beiranvand Z.,Lorestan University |
Madani F.,Lorestan University
Chemical Society Reviews | Year: 2013
Despite the great potential of carbon nanotubes (CNTs) in various areas of biomedicine, concerns regarding their carcinogenicity, inefficient dispersion in aqueous solutions and biological activity in vivo still remain. One important and feasible route to overcome these barriers is modification of CNTs with polymers, which are widely studied and play a vital role in biological and biomedical fields, especially in drug delivery. This comprehensive review focuses on the achievements of our and other groups in currently used methods to functionalize the surface of CNTs with polymers to produce anticancer drug delivery systems. We have intensively studied covalent and noncovalent interactions between CNTs and linear, dendritic and hyperbranched biocompatible polymers as well as biomacromolecules interactions which are very crucial to diminish the toxicity of CNTs via changing their conformations. © 2013 The Royal Society of Chemistry.
Farhadi S.,Lorestan University |
Safabakhsh J.,Lorestan University
Journal of Alloys and Compounds | Year: 2012
Co 3O 4 nanoparticles were easily prepared via the decomposition of the pentammine(carbonato)cobalt(III) nitrate precursor complex [Co(NH 3) 5CO 3]NO 3·0.5H 2O at low temperature (175 °C). The product was characterized by thermal analysis, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), UV-visible spectroscopy, transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), Raman spectroscopy, Brunauer-Emmett-Teller (BET) specific surface area measurements and magnetic measurements. The FT-IR, XRD, Raman and EDX results indicated that the synthesized Co 3O 4 nanoparticles are highly pure and have a single phase. The TEM analysis revealed nearly uniform and quasi-spherical Co 3O 4 nanoparticles with an average particle size of approximately 10 nm. The optical absorption spectrum of the Co 3O 4 nanoparticles showed two direct band gaps of 2.18 and 3.52 eV with a red shift in comparison with previous reported values. The prepared Co 3O 4 nanoparticles showed a weak ferromagnetic behaviour that could be attributed to uncompensated surface spins and/or finite-size effects. Using the present method, Co 3O 4 nanoparticles can be produced without expensive organic solvents and complicated equipment. This simple, rapid, safe and low-cost synthetic route can be extended to the synthesis of other transition-metal oxides. © 2011 Elsevier B.V. All rights reserved.
Alirezaei M.,Lorestan University
Journal of physiology and biochemistry | Year: 2011
Oxidative stress is a hypothesis for the association of reactive oxygen species with cerebrovascular and neurodegenerative diseases. Thus, we examined whether oral betaine can act as a preventive agent in ethanol-induced oxidative stress on the cerebellum of rats. Thirty-two adult male Sprague-Dawley rats were divided into four equal groups (control, ethanol, betaine, and betaine plus ethanol) with different dietary regimens and were followed up for 1 month. Total homocysteine (tHcy) of plasma and cerebellum homogenate was determined by an Axis(®) homocysteine EIA kit, and antioxidant enzyme (glutathione peroxidase (GPx), SOD, and CAT) activities of cerebellum homogenate were measured chemically by a spectrophotometer. Lipid peroxidation of cerebellum was shown by the measurement of thiobarbituric reactive substances (TBARS) via a spectrophotometer. Ethanol-induced hyperhomocysteinemia was manifested by an increase in the concentrations of tHcy in the plasma and cerebellum homogenates of the ethanol group, while ethanol-induced oxidative stress was indicated via an increase in lipid peroxidation marker (TBARS) in cerebellum homogenates of ethanol-treated rats. In contrast, betaine prevented hyperhomocysteinemia and oxidative stress in the betaine plus ethanol group as well as the betaine group. The results of the present investigation indicated that the protective effect of betaine is probably related to its ability to strengthen the cerebellum membrane cells by enhancement of antioxidant enzyme activity principally GPx, while the methyl donor effect of betaine to reduce hyperhomocysteinemia has been explained previously and confirmed in the present study.
Amiri H.,Lorestan University
Evidence-based Complementary and Alternative Medicine | Year: 2012
The essential oils of three wild-growing Thymus species, collected from west of Iran during the flowering stage, were obtained by hydrodistillation and analyzed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC-MS). Under the optimum extraction and analysis conditions, 44, 38, and 38 constituents (mainly monoterpenes compounds) were identified in T. kotschyanus Boiss. and Hohen, T. eriocalyx (Ronniger) Jalas, and T. daenensis subsp lancifolius (Celak) Jalas which represented 89.9, 99.7, and 95.8 of the oils, respectively. The main constituents were thymol (16.4-42.6), carvacrol (7.6-52.3), and γ-terpinene (3-11.4). Antioxidant activity was employed by two complementary test systems, namely, 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical scavenging and Β-carotene/linoleic acid systems. Antioxidant activity of polar subfraction of T. daenensis subsp lancifolius (Celak) Jalas was found to be higher than those of the others in DPPH assay, while nonpolar subfraction of T. eriocalyx (Ronniger) Jalas has most antioxidant activity in -Βcarotene/linoleic acid test (19.1±0.1 g/mL and 96.1±0.8 inhibition rate, resp.).
Shahbazi F.,Lorestan University
Journal of the Science of Food and Agriculture | Year: 2013
Background: Wild mustard seed is similar in size and shape to canola seed and can be separated by pneumatic means if the aerodynamic properties of these two materials are well known. The objective of this study was evaluation of the aerodynamic properties of canola and wild mustard seeds as a function of moisture content from 5% to 20% (w.b). Results: The results showed that the terminal velocity of canola seeds increased, following a polynomial relationship from 5.401 to 6.566 m s-1, as the moisture content increased from 5% to 20%. Over this same moisture content range the terminal velocity of wild mustard seeds varied from 4.276 to 5.433 m s-1. The drag coefficient of canola and wild mustard seeds decreased linearly from 1.062 to 0.646 and from 1.432 to 0.928, respectively, as moisture content increased from 5% to 20%. Analysis of variance showed that there was a significant difference between the terminal velocity and drag coefficient of canola and wild mustard seed at a 1% probability level. Conclusion: The results suggest that aerodynamic separation of wild mustard seed from canola is possible. Moisture content had a significant effect on the terminal velocity and drag coefficient of seeds. © 2012 Society of Chemical Industry.
Spinel-type zinc aluminate (ZnAl2O4) nanoparticles prepared by the co-precipitation method: A novel, green and recyclable heterogeneous catalyst for the acetylation of amines, alcohols and phenols under solvent-free conditions
Farhadi S.,Lorestan University |
Panahandehjoo S.,Lorestan University
Applied Catalysis A: General | Year: 2010
Zinc aluminate (ZnAl2O4) nanoparticles with an average particle size of about 8 nm were easily prepared by the co-precipitation method using aqueous ammonia solution as the precipitating agent. This nanosized spinel-type oxide was characterized by TGA, XRD, FT-IR, TEM, and surface area measurement and used as the heterogeneous catalyst for the acetylation reaction. Efficient acetylation of various amines, alcohols and phenols was carried out over ZnAl2O4 nanoparticles using acetic anhydride and/or acetyl chloride as the acetylating agents at room temperature without the use of a solvent. The method is highly selective, allowing the alcoholic hydroxyl group to be protected while the phenolic hydroxyl group remains intact, and the amine group can be acetylated in the presence of the hydroxyl group. This method is fast and has a high yield. It is also clean, safe, cost effective, compatible with substrates that have other functional groups and very suitable for practical organic synthesis. In addition, the catalyst can be reused without significant loss of activity. Indeed, the catalytic activity of the ZnAl2O4 nanoparticles is higher than that of bulk ZnAl2O4. © 2010 Elsevier B.V. All rights reserved.
Khodabakhshi M.,Lorestan University
Computers and Industrial Engineering | Year: 2010
In this paper, the concept of chance constrained programming approaches is used to develop output oriented super-efficiency model in stochastic data envelopment analysis. Output oriented super-efficiency model is one of the classic models in data envelopment analysis widely used by DEA people and practitioners. However, in many real applications, data is often imprecise. A successful method to address uncertainty in data is replacing deterministic data by random variables, leading to stochastic DEA. Therefore, in this paper, output oriented super-efficiency model is developed in stochastic data envelopment analysis, and its deterministic equivalent which is a nonlinear program is derived. Moreover, it is shown that the deterministic equivalent of the stochastic super-efficiency model can be converted to a quadratic program. Furthermore, sensitivity analysis of the proposed super-efficiency model is also discussed with respect to changes on parameter variables. Finally, data related to seventeen Iranian electricity distribution companies is used to illustrate the methods developed in this article. © 2010 Elsevier Ltd. All rights reserved.
Lorestan University | Date: 2011-02-16
This invention provides the synthesis of biocompatible and high functional hybrid nanomaterials consisting of pseudorotaxanes, pseudopolyrotaxanes, rotaxanes, polyrotaxanes, nanoparticles and quantum dots (QDs). The molecular self-assembly of hybrid nanomaterials lead to the formation of nano-objects with different shapes such as core-shell, spindle-like or necklaces. Due to their well-defined molecular self-assemblies, carbohydrate backbone, high functionality and several types of functional groups together with the high luminescence yield, thermal and physical properties and synthesized hybrid nanostructures were recognized as promising candidates for a wide range of applications.