Sharif Digital Repository

In this study, the properties of poly (vinyl alcohol)(PVA) films incorporated with Zataria multiflora essential oil (ZMO) as a potential antioxidant/antibacterial material was investigated. PVA films were prepared from PVA solutions (2% w/v) containing different concentrations of ZMO. Water solubility, moisture absorption, water swelling, and water vapor permeability for pure PVA films were 57 ± 1.1, 99 ± 3.2%, 337 ± 8%, and 0.453 ± 0.015 g mm/m2 h, respectively. Incorporation of ZMO into PVA films caused a significant decrease in water swelling and moisture absorption and increase in solubility and water vapor permeability. Tensile strength, elastic modulus, and elongation at break for pure... 

In this paper, first we present a new explanation for the relationship between logical circuits and artificial neural networks, logical circuits and fuzzy logic, and artificial neural networks and fuzzy inference systems. This shows us that neural networks are working in the same way as logical circuits when the connection between them is through the fuzzy logic. However, themain difference between them is that logical circuits can be constructed without using any kind of optimization-based learning methods. Based on these results, we propose a new neuro-fuzzy computing system. As verified by simulation results, it can effectively be implemented on the memristor crossbar structure and... 

This study introduces a new method for forecasting future states of nuclear power plants (NPPs) parameters in abnormal conditions (i.e. transients). The proposed method consists of two steps. First, the type of transients is recognized by the modular EBP based identifier. A hybrid network is then used to forecast the selected parameters of the identified transient. ARIMA model is used to estimate the linear component of the selected parameters. The neural network developed by EBP learning algorithm is then used to estimate the nonlinear component of the selected parameters. Finally, prediction of parameters is obtained by adding the estimated linear and nonlinear components. To analyze the... 

A two dimensional rectangular microchannel with circular micropillars was modeled in the presence of an electric field. Continuity and Navier-Stokes equations were solved along with convection-diffusion equation using finite element method. Reaction phenomenon was applied via a partial differential equation on the reaction surfaces and electric force was added as a source term to the transport equations. Velocity, concentration and electric potential distributions were obtained, with the aid of which, capture efficiency and average surface concentration of reaction surfaces were calculated. To ameliorate the reaction rate, different designs of reaction surfaces were investigated; the designs... 

A circuit model based on the transmission line theory is proposed to analyze the recently introduced metal-insulator-metal (MIM) complementary split-ring resonators (CSRRs). It is shown that integer and noninteger modes of CSRRs can be characterized by transmission line models with short- and open-circuited terminals. The proposed circuit model is then extended to incorporate side-coupling effects between the CSRRs and straight MIM waveguides. Thereby, simple closed-form expressions are provided for the coupling quality factor. It is shown that waveguide resonator structures based on CSRRs at specific resonance frequency and bandwidth can be smaller than waveguide resonator structures based... 

Context. The extrasolar planet WASP-67 b is the first hot Jupiter definitively known to undergo only partial eclipses. The lack of the second and third contact points in this planetary system makes it difficult to obtain accurate measurements of its physical parameters  

Dijet production has been measured in pPb collisions at a nucleon–nucleon centre-of-mass energy of 5.02 TeV. A data sample corresponding to an integrated luminosity of 35 nb−1 was collected using the Compact Muon Solenoid detector at the Large Hadron Collider. The dijet transverse momentum balance, azimuthal angle correlations, and pseudorapidity distributions are studied as a function of the transverse energy in the forward calorimeters (E4<|η|<5.2 T). For pPb collisions, the dijet transverse momentum ratio and the width of the distribution of dijet azimuthal angle difference are comparable to the same quantities obtained from a simulated pp reference and insensitive to E4<|η|<5.2 T. In... 

The reaction of a solution of MoO2(acac)2 in CH3OH and salicylidene 2-picoloyl hydrazone as a tridentate ONO donor Schiff base (ONO) afford a six-coordinated Mo(VI) complex [MoO2(ONO)(CH3OH)], with a distorted octahedral configuration. [MoO2(ONO)(CH3OH)] was isolated as an air-stable crystalline solid and fully characterized by single-crystal X-ray structure analysis. [MoO2(ONO)(CH3OH)] shows reactivity in the oxidation of sulfides to their corresponding sulfoxides using urea hydrogen peroxide as the oxidant at room temperature under air  

In order to simulate the performance of pure methane in chemical looping using iron-based oxygen carrier, simultaneously production of three pure streams of hydrogen, nitrogen and carbon dioxide has been investigated. For this purpose, proper operating conditions have been discussed for maximum production of hydrogen, complete consumption of oxygen of inlet air and complete combustion of methane. Professional software is used to simulate the chemical looping reactors and optimize their output streams. Results show that in this process each mole of methane fuel can produce 2.533, 2.65 and 0.99 mol of pure N 2, H2 and CO2, respectively which contributes 80.2% energy conversion of CH4 to H2.... 

A search for excited quarks decaying into the γ + jet final state is presented. The analysis is based on data corresponding to an integrated luminosity of 19.7 fb-1 collected by the CMS experiment in proton-proton collisions at √s=8TeV at the LHC. Events with photons and jets with high transverse momenta are selected and the γ + jet invariant mass distribution is studied to search for a resonance peak. The 95% confidence level upper limits on the product of cross section and branching fraction are evaluated as a function of the excited quark mass. Limits on excited quarks are presented as a function of their mass and coupling strength; masses below 3.5 TeV are excluded at 95% confidence... 

Numerical simulation of the electrical field distribution helps in-depth understanding of the mechanisms behind the responses and the benefits of the high voltage pulse comminution. The COMSOL Multiphysics package was used to numerically simulate the effect of ore compositions in this study. Regarding phosphate ore particles shape and composition, the effects of mineral composition, particle size, particle shape and electrodes distance were investigated on the electrical field intensity and distribution. The results show that the induced electrical field is significantly dependent on the electrical properties of minerals, the feed particle size and the location of conductive minerals in... 

Co-deposition of RF-sputtering and RF-PECVD from acetylene gas and Au target were used to prepare sensor chip of gold nanoparticles (Au NPs). Deposition conditions were optimized to reach a Localized Surface Plasmon Resonance (LSPR) sensor chip of Au NPs with particle size less than 10 nm. The RF power was set at 180 W and the initial gas pressure was set at 0.035 mbar. Transmission Electron Microscopy (TEM) images and Atomic Force Microscopy (AFM) data were used to investigate particles size and surface morphology of LSPR sensor chip. The Au and C content of the LSPR sensor chip of Au NPs was obtained from X-ray photoelectron spectroscopy (XPS). The hydrogenated amorphous carbon (a-C:H)... 

Consider a binary-input memoryless outputsymmetric channel W. Such a channel has a capacity, call it I (W), and for any R < I (W) and strictly positive constant Pewe know that we can construct a coding scheme that allows transmission at rate R with an error probability not exceeding Pe. Assume now that we let the rate R tend to I (W) and we ask how we have to scale the blocklength N in order to keep the error probability fixed to Pe. We refer to this as the finite-length scaling behavior. This question was addressed by Strassen as well as Polyanskiy, Poor, and Verdu, and the result is that N must grow at least as the square of the reciprocal of I (W)- R. Polar codes are optimal in the sense... 

The authors present the results of numerical tests and simulations to investigate and analyze the likelihood of asphaltene precipitation and deposition during CO2 flooding in a reservoir. The effects of asphaltene precipitation on oil properties such as oil viscosity and density during miscible CO2 flooding process were elaborated by using Winprop software of Computer Modeling Group. Also oil properties change during CO 2 miscible flooding by numerical slim tube were investigated by a compositional simulator (GEM). A fluid sample of Saskatchewan Reservoir that had been flooded miscibly with CO2 was chosen for performing the sensitivity analyses. The results showed that asphaltene... 

The lipid bilayer plays a crucial role in gating of mechanosensitive (MS) channels. Hence it is imperative to elucidate the rheological properties of lipid membranes. Herein we introduce a framework to characterize the mechanical properties of lipid bilayers by combining micropipette aspiration (MA) with theoretical modeling. Our results reveal that excised liposome patch fluorometry is superior to traditional cell-attached MA for measuring the intrinsic mechanical properties of lipid bilayers. The computational results also indicate that unlike the uniform bilayer tension estimated by Laplace's law, bilayer tension is not uniform across the membrane patch area. Instead, the highest tension... 

We analyze the impact of loss in lattices of coupled optical waveguides and find that, in such a case, the hopping between adjacent waveguides is necessarily complex. This results not only in a transition of the light spreading from ballistic to diffusive, but also in a new kind of diffraction that is caused by loss dispersion. We prove our theoretical results with experimental observations  

A search for supersymmetry through the direct pair production of top squarks, with Higgs (H) or Z bosons in the decay chain, is performed using a data sample of proton-proton collisions at s=8 TeV collected in 2012 with the CMS detector at the LHC. The sample corresponds to an integrated luminosity of 19.5 fb-1. The search is performed using a selection of events containing leptons and bottom-quark jets. No evidence for a significant excess of events over the standard model background prediction is observed. The results are interpreted in the context of simplified supersymmetric models with pair production of a heavier top-squark mass eigenstate t~2 decaying to a lighter top-squark mass... 

The ratio of the top-quark branching fractions R=B(t→Wb)/B(t→Wq), where the denominator includes the sum over all down-type quarks (q = b, s, d), is measured in the tt- dilepton final state with proton-proton collision data at s=8 TeV from an integrated luminosity of 19.7 fb-1, collected with the CMS detector. In order to quantify the purity of the signal sample, the cross section is measured by fitting the observed jet multiplicity, thereby constraining the signal and background contributions. By counting the number of b jets per event, an unconstrained value of R=1.014±0.003(stat.)±0.032(syst.) is measured, in a good agreement with current precision measurements in electroweak and flavour...