Search for: linear-dependencies
Ag Raman modes and ion-position dependence of the electronic structures of Y Ba2 Cu3 O7 and Y Ba2 Cu4 O8 from first principles, Article Physical Review B - Condensed Matter and Materials Physics ; Volume 76, Issue 5 , 2007 ; 10980121 (ISSN) ; Mossalla, B ; Akhavan, M ; Sharif University of Technology
Calculations of the frozen phonon for Ag Raman modes of the superconducting Y Ba2 Cu3 O7 and Y Ba2 Cu4 O8 systems have been carried out using the pseudopotential density functional theory in the local density approximation employing the VASP code. The eigenvalues and eigenvectors of the Ag Raman modes for the two systems have been calculated and compared with other experimental and computational studies. Electronic band structure and total density of states have been calculated for all the bare Ag modes for both systems. By calculating the changes in the bands intersecting the Fermi energy by ionic displacements, the ionic dependence of the electronic band structure in each of the Ag Raman...
Article ASME 2014 12th Biennial Conference on Engineering Systems Design and Analysis, ESDA 2014 ; Vol. 1 , 2014 ; Asghari, M ; Sharif University of Technology
In Hypo-elastic constitutive models an objective rate of the Cauchy stress tensor is expressed in terms of the current state of the stress and the deformation rate tensor D in a way that the dependency on the latter is a homogeneously linear one. In this work, a type of grade-one hypo-elastic models (i.e. models with linear dependency of the hypo-elasticity tensor on the stress) is considered for isotropic materials based on the objective corotational rates of stress. A positive real parameter denoted by n is involved in the considered type. Different values can be selected for this parameter, each selection leads to a specific model within the class of grade-one hypo-elasticity. The spin of...
Article Physical Review E ; Volume 102, Issue 1 , 2020 ; Ebrahimi, M ; Riazi, M ; Hosseiny, A ; Jafari, G. R ; Sharif University of Technology
American Physical Society 2020
Balance theory proposed by Heider for the first time modeled triplet interaction in a signed network, stating that relationships between two people, friendship or enmity, is dependent on a third person. The Hamiltonian of this model has an implicit assumption that all triads are independent, meaning that the type of each triad, being balanced or imbalanced, determined apart from the state of other triads. This independence forces the network to have completely balanced final states. However, there exists evidence indicating that real networks are partially balanced, raising the question of what is the mechanism preventing the system to be perfectly balanced. Our suggestion is to consider a...
Linear and nonlinear model of cutting forces in peripheral milling: A comparison between the accuracy of 2D and 3D models, Article 2009 ASME International Mechanical Engineering Congress and Exposition, IMECE2009, Lake Buena Vista, FL, 13 November 2009 through 19 November 2009 ; Volume 3 , 2010 , Pages 955-962 ; 9780791843765 (ISBN) ; Movahhedy, M. R ; Vossoughi, G ; Sharif University of Technology
Peripheral milling is extensively used in manufacturing processes, especially in aerospace industry where end mills are used for milling of wing parts and engine components. Knowledge of the cutting forces is the first necessary stage in analysis of the milling process. In this paper, cutting forces are presented for both two and three dimensional models. Instead of the common linear dependency of cutting forces to the cut chip thickness, two nonlinear models are presented. In the first model, cutting forces are considered as a function of chip thickness with a complete third order polynomial. In the second one, the quadratic and constant terms of the third order polynomial are set to zero....
Adsorption of proteins at the solution/air interface influenced by added nonionic surfactants at very low concentrations for both components. 3. dilational surface rheology, Article Journal of Physical Chemistry B ; Volume 119, Issue 9 , January , 2015 , Pages 3768-3775 ; 15206106 (ISSN) ; Aksenenko, E. V ; Lylyk, S. V ; Lotfi, M ; Miller, R ; Sharif University of Technology
The influence of the addition of the nonionic surfactants C
12DMPO, C 14DMPO, C 10OH, and C 10EO 5 at concentrations between 10-5 and 10-1 mmol/L to solutions of β-casein (BCS) and β-lactoglobulin (BLG) at a fixed concentration of 10-5 mmol/L on the dilational surface rheology is studied. A maximum in the viscoelasticity modulus |E| occurs at very low surfactant concentrations (10-4 to 10-3 mmol/L) for mixtures of BCS with C 12DMPO and C 14DMPO and for mixtures of BLG with C 10EO 5, while for mixture of BCS with C 10EO 5 the value of |E| only slightly increased. The |E| values...
Article Electrochimica Acta ; Volume 55, Issue 6 , 2010 , Pages 2093-2100 ; 00134686 (ISSN) ; Jafarian, M ; Mirzapoor, A ; Gobal, F ; Mahjani, M. G ; Sharif University of Technology
Nickel and nickel-manganese alloy modified graphite electrodes (G/Ni and G/NiMn) prepared by galvanostatic deposition were examined for their redox process and electrocatalytic activities towards the oxidation of methanol in alkaline solutions. The methods of cyclic voltammetery (CV), chronoamperometry (CA) and impedance spectroscopy (EIS) were employed. In CV studies, in the presence of methanol NiMn alloy modified electrode shows a significantly higher response for methanol oxidation. The peak current of the oxidation of nickel hydroxide increase is followed by a decrease in the corresponding cathodic current in presence of methanol. The anodic peak currents show linear dependency upon the...
Article Journal of Solid State Electrochemistry ; Volume 13, Issue 8 , 2009 , Pages 1171-1179 ; 14328488 (ISSN) ; Forouzandeh, F ; Danaee, I ; Gobal, F ; Mahjani, M. G ; Sharif University of Technology
Nickel and nickel-copper alloy modified glassy carbon electrodes (GC/Ni and GC/NiCu) prepared by galvanostatic deposition were examined for their redox processes and electro-catalytic activities towards the oxidation of glucose in alkaline solutions. The methods of cyclic voltammetry (CV) and chronoamperometry (CA) were employed. The cyclic voltammogram of NiCu alloy demonstrates the formation of β/β crystallographic forms of the nickel oxyhydroxide under prolonged repetitive potential cycling in alkaline solution. It is also observed that the overpotential for O 2 evolution increases for NiCu alloy modified electrode. In CV studies, NiCu alloy modified electrode yields significantly higher...
Article Journal of Biomechanics ; Volume 44, Issue 1 , Jan , 2011 , Pages 170-175 ; 00219290 (ISSN) ; Ishikawa, T ; Matsuki, N ; Jafar Abdekhodaie, M ; Imai, Y ; Ueno, H ; Yamaguchi, T ; Sharif University of Technology
Fluid particle diffusion through blood flow within a capillary tube is an important phenomenon to understand, especially for studies in mass transport in the microcirculation as well as in solving technical issues involved in mixing in biomedical microdevices. In this paper, the spreading of tracer particles through up to 20% hematocrit blood, flowing in a capillary tube, was studied using a confocal micro-PTV system. We tracked hundreds of particles in high-hematocrit blood and measured the radial dispersion coefficient. Results yielded significant enhancement of the particle diffusion, due to a micron-scale flow-field generated by red blood cell motions. By increasing the flow rate, the...
Article International Journal of Hydrogen Energy ; Volume 33, Issue 16 , August , 2008 , Pages 4367-4376 ; 03603199 (ISSN) ; Jafarian, M ; Forouzandeh, F ; Gobal, F ; Mahjani, M. G ; Sharif University of Technology
Nickel and nickel-copper alloy modified glassy carbon electrodes (GC/Ni and GC/NiCu) prepared by galvanostatic deposition were examined for their redox process and electrocatalytic activities towards the oxidation of methanol in alkaline solutions. The methods of cyclic voltammetery (CV) and chronoamperometry (CA) were employed. The cyclic voltammogram of NiCu alloy demonstrates the formation of β/β crystallographic forms of the nickel oxyhydroxide under prolonged repetitive potential cycling in alkaline solution. In CV studies, in the presence of methanol NiCu alloy modified electrode shows a significantly higher response for methanol oxidation. The peak current of the oxidation of nickel...