Rashno A.,Young Researchers and Elite Club |
Rezaee Niaraki P.,Institute of Mechanical Wood Technology
Polymer Composites | Year: 2016
The effects of a silane coupling agent such as (N-(n-butyl)-3-aminopropyltrimethoxy silane) on old corrugated container (OCC) fibers, as a recyclable material, were studied on the ultimate strength of the prepared OCC fibers/high density polyethylene composites. Raw materials were mixed in a counter-rotating twin-screw extruder and injection molding machine was used to make samples. Various characterization methods, based on ASTM standard, were conducted to evaluate physical properties (water absorption and thickness swelling) and mechanical behavior (tensile, flexural, impact, hardness, and elongation-at-break) of the composites. Also, the thermal properties of the specimens were recorded by differential scanning calorimeter (DSC) and thermogravimetric analysis (TGA). Finally the results of the treated samples were compared with the non-treated and pure polymer specimens. The obtained results showed that increasing coupling agents by a maximum of 2 wt% enhanced mechanical behavior (including flexural and tensile strengths), thermal stability, and increased crystallinity of the composites. Moreover, water absorption and thickness swelling of composite materials declined. Morphological studies by scanning electron microscopy methods (SEM) indicated that fiber pull-out decreased in treated samples and coupling agent facilitated strong adhesion in fiber/polymer interface. The highest flexural strength and modulus were obtained in composites with 2 wt% silane coupling agent and 30 wt% OCC fibers. © 2016 Society of Plastics Engineers.
Tahouneh V.,Young Researchers and Elite Club
Polymer Composites | Year: 2016
This article deals with free vibration analysis of thick nanocomposite laminated curved panels with finite length resting on two-parameter elastic foundations, based on the three-dimensional elasticity theory. The main objective of this research paper is to present a 3D elasticity solution for free vibration analysis of thick laminated curved panels with continuously graded carbon nanotube-reinforced (CGCNTR) sheets. The structure is supported by an elastic foundation with Winkler's (normal) and Pasternak's (shear) coefficients. The volume fractions of oriented, straight single-walled carbon nanotubes (SWCNTs) are assumed to be a three-parameter power-law distribution which is graded in the radial direction of the panels. An equivalent continuum model based on the Eshelby-Mori-Tanaka approach is employed to estimate the effective constitutive law of the elastic isotropic medium (matrix) with oriented, straight carbon nanotubes (CNTs). Because of using two-dimensional generalized differential quadrature method, the present approach makes possible vibration analysis of cylindrical panels with two opposite axial edges simply supported and arbitrary boundary conditions including Free, Simply supported and Clamped at the curved edges. The convergence of the method is demonstrated and comparisons are made between the present results and results reported by well-known references and have confirmed accuracy and efficiency of the present approach. This study serves as a benchmark for assessing the validity of numerical methods or two-dimensional theories used to analysis of laminated curved panels. © 2016 Society of Plastics Engineers.
Kamarian S.,Young Researchers and Elite Club |
Bodaghi M.,Young Researchers and Elite Club |
Pourasghar A.,Young Researchers and Elite Club
Polymer Composites | Year: 2016
The present work deals with natural frequency analysis of non-uniform nanocomposite beams with surface-bonded piezoelectric layers by considering the agglomeration effect of Carbon Nanotubes (CNTs). The material properties of the nanocomposite beam are predicted employing Eshelby-Mori-Tanaka approach based on an equivalent fiber and compared with available experimental data in the literature. The equation of motion is derived employing Hamilton's principle and Generalized Differential Quadrature technique as an efficient and accurate numerical tool is employed for free vibration analysis of the structures. Detailed parametric studies are carried out to examine influences of CNTs volume fraction, CNTs agglomeration, thickness of piezoelectric layers, piezoelectric constant, dielectric constant, boundary conditions etc., on the behavior of freely vibrating smart structure. Results represent that for some cases, consideration of agglomeration effect of CNTs is not required while for some other cases it has a significant role on the response. The numerical results also reveal that using thick piezoelectric layer does not necessarily improve the natural frequency of the structure. © 2016 Society of Plastics Engineers.
Mokhtarian M.,Young Researchers and Elite Club
Journal of Food Process Engineering | Year: 2016
The effects of storage temperatures (15, 25, 35, and 40°C) and relative humidity (11, 33, 73 and 87%) on peroxide value, lipid oxidation and shelf life of stored pistachio powder studied in this project. Results showed that the changes in lipid oxidation follow zero-order reaction kinetic. Additionally, the highest inhibition (or activation) energy (Ea) for oxidation of fatty acid molecules and forming hydro-peroxides reached to ∼50 kJ/mol at relative humidity of 33%, which corresponds to monolayer moisture content of pistachio powder. Thermodynamic analysis of these reactions indicated that these reactions are endothermic (ΔH++>0) and nonspontaneous (ΔG++>0) processes. Practical Applications: Pistachio nut (Pistachia vera L.) is one of the most popular nuts in the world with its high nutritional value and unique flavor as a snack and a food ingredient (as powder or kernel). It is also used as a main part of many traditional Persian foods such as Gaz, Baghlava and Ghotab. Fat oxidation is one of the main factors for quality loss in pistachio, i.e., changes in nutritional and organoleptic properties of this product during storage period. The main object of this research is the kinetic effects of different storage temperature and RH on auto-oxidation of pistachio powder's lipid during storage period. Generally, the results are applicable by pistachio powder's workstations and their producing factories during processing and storage for controlling the shelf life. © 2016 Wiley Periodicals, Inc.
Azizi R.,Young Researchers and Elite Club |
Hasanzadeh H.,Ferdowsi University of Mashhad
6th International Conference on Computing, Communications and Networking Technologies, ICCCNT 2015 | Year: 2015
Present study attempts to offer approved investigation of locating the nearest server to a group of content-equivalent ones in a wireless ad hoc network. Different mobility models are used to measure the performance of wireless ad hoc networks with an anycast mechanism in an outdoor environment. Anycasting is defined as a useful communication sample for ad hoc networks in which resource adequacy and robustness is significantly important. All the network configurations are done by laptop computers with windows vista operating system. A multithread program which is based on an application layer anycast one is applied to evaluate the network functionality. The operation of five main performance criteria-response ratio, duplicate ratio, average number of hops, average response time and relative network traffic were studied in which different models were applied. © 2015 IEEE.
Hossein A.,Islamic Azad University at Baft |
Safdar A.,Islamic Azad University at Baft |
Safdar A.,Young Researchers and Elite Club
Indian Journal of Animal Sciences | Year: 2016
Bovine somatotropin (bST) was administered @ 50 and 100 mg at the beginning of the estrus synchronization and natural mating of the sheep to evaluate the improvement of the ovulation rate, embryonic development and pregnancy rate of the transferred embryos. Donors (48) were treated with 3 different types of treatment; group A (15): treated with bST-100, received 100 mg of bST at the beginning of the synchronization and natural mating, group B (15): treated with 50 mg of bST same as the previous group and control (18) did not receive any type of bST. Each recipient (108) received 2 embryos: 30 recipients received embryos from bST-100s, 45 received the embryos from bST-50 and 33 received embryos from the control group. Using SAS related GENMOD method, superovulatory response, embryo recovery, cleavage rate, transferable embryo percentage, quality of embryos, rates of pregnancy and embryonic development were analyzed. Using GLM procedure, numbers of corpus luteum and blastocyst cells were analyzed. The results showed that bST administration had no significant effect on superovulatory response, number of CL and recovered structures. Number of transferable embryos and embryos that had reached to the blastocyst in bST-50 was more than bST-100 and control group. In conclusion, treatment 50 mg bovine somatotropins enhance the ratio and growth of the transferable embryos. Embryos of bST-50 treatment indicated an improved embryonic development but bST did not affect the pregnancy rates of transferred embryos. © 2016, Indian Council of Agricultural Research. All rights reserved.
Ahmadi M.,Young Researchers and Elite Club |
Sami A.,Shiraz University |
Rahimi H.,Shiraz University |
Yadegari B.,Shiraz University
Computer Fraud and Security | Year: 2013
For many years, malware has been the subject of intensive study by researchers in industry and academia. Malware production, while not being an organised business, has reached a level where automatic malicious code generators/engines are easily found. These tools are able to exploit multiple techniques for countering anti-virus (AV) protections, from aggressive AV killing to passive evasive behaviours in any arbitrary malicious code or executable. Development of such techniques has lead to easier creation of malicious executables. Consequently, an unprecedented prevalence of new and unseen malware is being observed. Reports suggested a global, annual economic loss due to malware exceeding $13bn in 2007.1 Traditional signature-based antivirus methods struggle to cope with polymorphic, metamorphic and unknown malicious executables. And analysing and debugging obfuscated programs is a tricky and cumbersome process. Now Mansour Ahmadi of Young Researchers and Elite Club, Shiraz Branch, Iran and Ashkan Sami, Hossein Rahimi and Babak Yadegari of Shiraz University, Iran have developed a novel framework based on runtime API call auditing and data mining, a method that achieved a malware detection rate of 98.4% in tests. Here, they detail their approach and the benefits it could bring. © 2013 Elsevier Ltd.
Sayyadi S.Y.,Young Researchers and Elite Club |
Ardestani V.E.,University of Tehran
Near Surface Geoscience 2015 - 21st European Meeting of Environmental and Engineering Geophysics | Year: 2015
The most important goal in hydrocarbon explorations is finding undersurface anomalies which have good quality for gas and oil explorations. Gravity data can be useful in fields with salt body structures. In our case study, Charak anticline has some out growing salt bodies. This anticline has arc image, it looks that an undersurface anomaly make this image. In this paper, in this paper To clarify this anomaly we improve the precision of inversion result, with minimum inertia, in Lewi algorithm .the result shows a salt body which have at least 2kilometeres depth that is a good place for exploring gas and oil. © (2015) by the European Association of Geoscientists & Engineers (EAGE).
Pourasghar A.,Young Researchers and Elite Club |
Homauni M.,Young Researchers and Elite Club |
Kamarian S.,Young Researchers and Elite Club
Polymer Composites | Year: 2015
The present paper deals with the dynamic behavior of rotating nanobeam subjected to follower force using the nonlocal elasticity theory. The nonlocal elasticity theory is used to analyze the mechanical behavior of nanoscale materials. The used method of solution is the Differential Quadrature Method (DQM). It is shown that the frequencies are affected when the size effect is taken into consideration. The effects of the nonlocal small scale parameter and the hub radii on the natural frequencies of the rotating nanobeam with respect to the rotating angular velocity are investigated in the present work. This study could be useful in design of the next generation of nanodevices such as blades of a nanoturbine, nanogears, nanoscale molecular bearings, that make use of the vibration analysis of rotating nanobeam. © 2015 Society of Plastics Engineers.
Sadeghi Ghari H.,Young Researchers and Elite Club |
Shakouri Z.,Young Researchers and Elite Club
Journal of Vinyl and Additive Technology | Year: 2016
The present paper addresses the usefulness of a sorption gravimetric technique to assess of the compatibility and reinforcing effect of nanofiller against hazardous liquid media. The reinforcing capability of organoclay (Cloisite 30B) in chlorosulfonated polyethylene (CSM) was characterized by means of transport properties such as diffusion, sorption and permeation coefficients, activation energy, enthalpy, and entropy. The CSM/organoclay nanocomposites were prepared by melt mixing method. The transport of toluene through CSM vulcanizates were studied with special reference to the effect of organoclay concentration (0-9 parts per hundred parts of rubber) and temperature (25-55°C). The microstructure of the nanocomposites was confirmed by studying of dispersion of organoclay in CSM via transmission and scanning electron microscopy and X-ray diffraction. The results showed that the swelling properties of nano-filled CSMs mainly depend on the presence of organoclay and not its concentration and also the formed microstructure. A good relationship was found between the microstructure and swelling properties of CSM nanocomposites. © 2016 Society of Plastics Engineers.