Influence of pH on the Electrochemical Deposition of Composite Coatings in Copper Matrix with Tio2 Nanoparticles
Samira Salehi,
Masoud Delgosha,
Soheil Sharifi
Issue:
Volume 3, Issue 1, February 2014
Pages:
1-4
Received:
27 November 2013
Published:
30 January 2014
Abstract: Cu-nanoTiO2 composite coatings electroplated from copper sulfate bath were obtained and characterized.The paper presents the influence of the different pH of Cu– TiO2 coatings obtained at DC current density. The pHwere 0.5and2in electroplating bath.The surface morphology andcomposition of layers were studied by scanning electron microscopy (SEM) and EDX analysis.The influences of pH parameter on the thickness, grain size and surface morphology of coating were studied.
Abstract: Cu-nanoTiO2 composite coatings electroplated from copper sulfate bath were obtained and characterized.The paper presents the influence of the different pH of Cu– TiO2 coatings obtained at DC current density. The pHwere 0.5and2in electroplating bath.The surface morphology andcomposition of layers were studied by scanning electron microscopy (SEM) an...
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Determination of Effective Photon Lifetime in Nitrogenic Laser in One and Two Dimension
S. N. Hosseinimotlagh,
M. T. Yazdani,
H. Zare
Issue:
Volume 3, Issue 1, February 2014
Pages:
5-11
Received:
5 March 2014
Accepted:
12 April 2014
Published:
10 May 2014
Abstract: Since one of the most valuable measurable parameters in laser, called effective cavity lifetime , gives useful information about laser, this paper aims to study the description of it dependency, τ_ph^eff, on geometrical characteristics of N2-laser, electrodes length and amplifier gap separation. First based on the studies carried out on it , an oscillator-amplifier laser is used which operates under moderate current density conditions; Then in order to obtain a theoretical relation for effective cavity lifetime and to demonstrate the mentioned dependency using rate equations, at first a one-dimensional method is used for the photon density. Since the answers of rate equations in an oscillator-amplifier laser are complicated, a single-oscillator based modelis offered to make rate equations simpler. In this model, at first it is supposed that the photon density of inner part of the amplifier could benph (z,t)= nph (0,t) exp (g0(z)z), If nph≅ nph (z,t), then rate equations are used for this density and since g0 is a function of z or amplifier electrode length (Z≅lAMP), the cavity effective life time is calculated for equivalent oscillator.Then ,Since most of studies carried out in one dimension , so for approaching to more actual system a two -dimensional method is used for the photon density. So, we consider Z andY, which Z is along amplifier electrodes length and Y is along gaps separation. Supposing that Z and Y are independent on the photon density, two independent relations can be considered for the photon density. In this step, 2-dimensional photon density could be regarded as:nph (z,y,t) = nph (z,t) nph (y,t) . and then 2-dimensional effective cavity lifetime amount is obtained as:〖〖(τ〗_eff^ph)〗^(-1)=c/l_AMp (1+ ץ_l^z+bl_AMp ץ_l^z )+c/d_AMp (ץ_l^y+ad_AMp ץ_l^y ), This relation includes 2 independent values along the electrodes length (Z≅lAMP) and gap separation (y≅dAMP). It also demonstrates that the obtained 2-dimentional relation represents a perfect schema for lifetime behavior. The results of this calculation are consistent with other reported N2-laser effective cavity lifetime values measured under moderate current density conditions.
Abstract: Since one of the most valuable measurable parameters in laser, called effective cavity lifetime , gives useful information about laser, this paper aims to study the description of it dependency, τ_ph^eff, on geometrical characteristics of N2-laser, electrodes length and amplifier gap separation. First based on the studies carried out on it , an o...
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