Roduction of Solar Grade Silicon by Thermal Refining of Industrial Grade Silicon

, M.Sc. Thesis Sharif University of Technology Fazlali, Reza (Author) ; Yoozbashizadeh, Hossein (Supervisor)

Abstract

The photovoltaic (PV) industry is in rapid growth and a large supply of PV feedstock materials must be provided to maintain this growth. Since silicon is still the dominant material for the fabrication of solar cells, low-cost solar-grade silicon (SoG-Si) feedstock is demanded. The most cost-effective and direct approach for producing SoG-Si is to purify and upgrade metallurgical-grade silicon. The major impurities in silicon are Al, Fe and Ca. other impurities present are Cu, Ti , Zn, Ni, Cr, Mn, Cd, B and P. In this study The effects of the acid leaching process parameters, including the particle size of silicon, the acid type (HCl, HNO3, H2SO4, and their combination), tmepreture and the...

An analytical study on the elastic-plastic pure bending of a linear kinematic hardening curved beam

, Article International Journal of Mechanical Sciences ; Volume 144 , 2018 , Pages 274-282 ; 00207403 (ISSN) Fazlali, M. R ; Arghavani, J ; Eskandari, M ; Sharif University of Technology

Elsevier Ltd 2018

Abstract

In this study, an analytical solution is presented for elastic-plastic pure bending of a linear kinematic hardening curved beam with rectangular cross section both in monotonic loading and unloading. Compared to exact plane plasticity solution (already reported in the literature in loading) which needs solution of a system of equations, the proposed method is based on the hyperbolic strain distribution on the cross section which yields a simple approximate solution. To this end, we employ Winkler's theory, and assume plane cross sections remain plane after loading proved by the exact elasticity and plasticity solutions for pure bending of curved beams with rectangular cross section. At the...

Fast architecture for decimal digit multiplication

, Article Microprocessors and Microsystems ; Volume 39, Issue 4-5 , June–July , 2015 , Pages 296-301 ; 01419331 (ISSN) Fazlali, M ; Valikhani, H ; Timarchi, S ; Tabatabaee Malazi, T ; Sharif University of Technology

Elsevier 2015

Abstract

Abstract BCD digit multiplication module (BDM) is widely used in BCD arithmetic, especially in Decimal Floating-Point (DFP) units. In this paper, we present a new BCD digit multiplication scheme to accelerate this module. Similar to previous articles, our multiplier includes two parts contained binary multiplier and binary to BCD converter. Our contribution towards these modules can successfully overcome the previous BCD digit multipliers. The results indicate 19% hardware acceleration for the proposed multiplier architecture which is comparable to the best previous techniques in UMC 65 nm CMOS standard cells library hardware implementation. Therefore, the proposed BCD digit multiplier is an...

, M.Sc. Thesis Sharif University of Technology Fazlali, Masoume (Author) ; Moshfegh, Ali Reza (Supervisor) ; Akhavan, Omid (Supervisor)

Abstract

In photocatalitic activity of titana an effective approach to achieve high charge separation efficiency and high level of sensitivity under visible light is coupling it with another semiconductor with smaller band gap and appropriate banding energy structure. achieving all mentioned above, we used bilayer structure and coupled TiO2 with hematite which its small band gap(Eg ~ 2.1 ev) is sensitive to visible light. Bilayer systems of TiO2/Fe2O3 , Fe2O3/TiO2 were fabricated by sol-gel process and variable parameter was upper layer thickness. The layers were deposited on glass substrate via sol-gel process. The upper layers were prepared in different thicknesses in two ways. First, they...

Nonlinear flexure of Timoshenko–Ehrenfest nano-beams via nonlocal integral elasticity

, Article European Physical Journal Plus ; Volume 135, Issue 8 , 2020 Fazlali, M ; Faghidian, S. A ; Asghari, M ; Mohamadi Shodja, H ; Sharif University of Technology

Springer 2020

Abstract

Nonlinear flexural behavior of elastic nano-beams under static loads is investigated in the framework of the Eringen’s nonlocal integral elasticity. The integro-differential and boundary conditions of equilibrium for inflected Timoshenko–Ehrenfest elastic beams with von Kármán nonlinear strains are established by using the minimum total potential energy principle. Eringen’s nonlocal differential law, consequent (but not equivalent) to Eringen’s nonlocal integral convolution, is well established to be inconsistent when applied to bounded domains of nano-mechanics interest. Accordingly, nonlocal integral elasticity formulation is utilized to capture scale effects in the nonlinear flexure of...

An Analytical Study on the Pure Bending of SMA Curved Beams

, M.Sc. Thesis Sharif University of Technology Fazlali, Mohammad Reza (Author) ; Eskandari, Morteza (Supervisor) ; Arghavani Hadi, Jamal (Supervisor)

Abstract

In this thesis, an analytical solution is presented for pure bending of SMA curved beams with rectangular cross section and both loading and unloading stages are considered. Moreover, by appropriate simplification, its application in elastoplastic pure bending of curved beams made of regular materials is investigated. Elastic-linear kinematic hardening behavior of the material is assumed and both loading and unloading stages are considered. Exact plane plasticity solution of the elastoplastic pure bending of curved beams made of regular materials which exists in loading and is available for rectangular cross section has many unknowns and longsome equations. Therefore, it is difficult to use...