Terfous A.,IMFS |
Hazzab A.,Saida University |
Powder Technology | Year: 2013
This paper presents a relationship for calculating the drag coefficient of a spherical particle. The results obtained were validated using experimental data, including comparison with results from other relationships such as certainty analysis. The validation indicated that the proposed relationship is easier to apply and produces the best results. In addition, a relationship based on the characteristics of both the fluid and the particles was established to calculate directly the settling velocity of a spherical particle in a fluid at rest. The settling velocity values obtained with the proposed relationship were validated using experimental data and the model proved to be reliable and precise. © 2013 Elsevier B.V.
Bouchikhi A.,Saida University
Plasma Science and Technology | Year: 2012
This paper presents an investigation of a DC glow discharge at low pressure in the normal mode and with Einstein's relation of electron diffusivity. Two-dimensional distributions in Cartesian geometry are presented in the stationary state, including electric potential, electron and ion densities, longitudinal and transverse electrics fields as well as electron temperature. Our results are compared with those obtained in existing literature. The model used in this work is based on the first three moments of Boltzmann's equation. They serve as the continuity equation, the momentum transfer and the energy equations. The set of equations for charged particles presented in monatomic argon gas are coupled in a self-consistent way with Poisson's equation. A parametric study varying the cathode voltage, gas pressure, and secondary electron emission coefficient predicts many of the well-known features of DC discharges.
Abbas S.,Saida University |
Benchohra M.,University Djilali Liabes
Nonlinear Analysis: Hybrid Systems | Year: 2010
In this paper we investigate the existence of solutions for a class of initial value problems for impulsive partial hyperbolic differential equations involving the Caputo fractional derivative by using the lower and upper solutions method combined with Schauder's fixed point theorem. © 2009 Elsevier Ltd.
Shamseddine A.I.,American University of Beirut |
Farhat F.S.,Saida University
Chemotherapy | Year: 2011
The role of platinum-based compounds (PBCs) in the treatment of metastatic breast cancer (MBC) has been extensively studied. As single agents, high response rates have been observed in first-line therapy, while results in pretreated patients were discouraging. Regimens containing cisplatin/carboplatin together with taxanes showed the highest efficacy and safety as both first-line and second-line therapy. When administered with vinorelbine, the combination was also active and well tolerated in anthracycline- and taxane-pretreated patients. Combining PBCs with etoposide or nucleoside analogues showed moderate activity, yet high toxicity in the case of etoposide. The overall results for the combination with anthracyclines were disappointing. Addition of trastuzumab to PBC combinations showed remarkable activity and good tolerability in patients with HER2/neu overexpression. The use of cisplatin or carboplatin alongside novel targeted therapeutics for patients with triple-negative MBC seems promising and is being further evaluated. The use of PBCs against MBC requires careful patient selection and combination with the right chemotherapeutic agent. Copyright © 2012 S. Karger AG, Basel.
Abdelkader E.,University of Science and Technology of Oran |
Nadjia L.,Saida University |
Ahmed B.,University of Science and Technology of Oran
Applied Surface Science | Year: 2012
A novel nanoscale powder 20 wt%SrO-CuBi 2O 4 has been successfully synthesized for the first time by ion exchange through doping Sr(NO 3) 2 into CuBi 2O 4 matrix and characterized using TG/DTA, XRD, EDX, SEM and electrical measurements. The as-prepared 20 wt%SrO-CuBi 2O 4 composite exhibit much higher photocatalytic activity than 20 wt%SrO-CuBi 2O 4 synthesized via physical process and pure phase CuBi 2O 4 under UV-A light irradiation (λ = 365 nm) in the course of the photocatalytic redox activity of Congo red (CR). Maximum degradation was achieved within 220 min of irradiation time under UV-A light as a result of 97.22% of photocatalytic efficiency of CR. The mechanisms of the enhancement of photocatalytic activity of the nanocomposite photocatalyst will be discussed by the p-n heterojunction principle (charge separation and photochemical diode models) and the valance band theory. The pure nanocomposite systems have been also reported for a comparative purpose. © 2011 Elsevier B.V. All rights reserved.