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Gazan, Saudi Arabia

Ghaly M.Y.,Gazan University | Al-Maghrabi M.N.N.,King Abdulaziz University | Ismail E.,Gazan University | Ali M.E.M.,National Research Center of Egypt
Desalination and Water Treatment | Year: 2015

Abstract: The Advanced oxidation processes sunlight/photocatalyst is common for remediation treatments. During the oxidation processes, organic matter decomposed into smaller compounds, which affect the characteristics of the treated effluent. In the present work, two types of commercial TiO2 (TiO2 P-25 Degussa and commercial TiO2 (A)) were supported on small glass spirals. The photooxidation of natural organic matters (NOMs) over immobilized TiO2 using parabolic solar collector was investigated. The effects of addition of H2O2 as electron acceptor and pH values were also investigated. The degradation of NOMs was followed up by analysis of total organic carbon (TOC) and UV absorbance at 254 nm (A254). It was found that NOMs were completely removed over immobilized TiO2 on glass spirals under sunlight irradiation after 120 min. Also, approximately 77% of TOC was reduced from groundwater. Upon obtained results, solar energy could be used for photocatalytic degradation of NOMs in ground and surface waters and therewith lighten the process of preparing them to the potable water. © 2014 Balaban Desalination Publications. All rights reserved.

Abdel-Wahab B.F.,King Abdulaziz University | Khidre R.E.,Gazan University | Khidre R.E.,National Research Center of Egypt | Farahat A.A.,Mansoura University
Arkivoc | Year: 2011

This review deals with synthesis and reactions of pyrazole-3(4)- carbaldehydes as well as their biological activity. The data on the methods of synthesis, chemical reactions,and biological activity of these heterocycles published over the last years are reviewed here for the first time. © ARKAT-USA, Inc.

Ateto M.S.,South Valley University | Ateto M.S.,Gazan University
International Journal of Quantum Information | Year: 2015

Entanglement dynamics of two identical non-interacting atoms (qubits) coupled individually with simultaneous classical and quantum fields are studied. The cavity field is filled with a nonlinear Kerr medium and initially prepared in a coherent state. The atoms are initially set up as a Bell-like pure state (BS). We present an approach for diagonalization of time-dependent nonlinear Hamiltonian of the system exactly. Connection between the change in the degree of entanglement and tomography of field state in phase space are also illustrated and interpreted. We demonstrate the possibility of atom-atom (qubit-qubit) entanglement optimization by suitably choosing initial interaction settings. Overall, we show that both classical driving amplitude and detuning as well as Kerr media and initial atomic states acts as the control parameters for the qubit-qubit entanglement. By adjusting of these parameters, accurately, entanglement can be enhanced noticeably and high degree of steady periodical entanglement can be generated. Moreover, starting with initial atomic BSs in presence of classical driving suppresses coherences randomness and considerably accompanied with (for specific values of detuning) slight decrease in their amplitudes. Furthermore, the addition of cross Kerr term suppresses degree of entanglement noticeably, where entanglement creation and enhancement could just be possible if cross Kerr effect is moved out from interaction. Our present approach promises the great advantage of being suitable for large quantum systems of various kinds of nonlinearities. © 2015 World Scientific Publishing Company.

Bakry M.,Gazan University | Mousa M.O.,Minia University | Ali W.Y.,Taif University
Materialwissenschaft und Werkstofftechnik | Year: 2013

In the present work, friction material composites were proposed to be used as automotive friction materials. The composites were reinforced by agricultural fibres of corn, palm, and sugar bars. The conventional friction materials based on asbestos cause serious lung diseases and being cancerous potential. The aim of the present work is to replace them by the proposed composites because they are environmentally friendly friction material for brake lining and clutch facings. Agricultural wastes of sugar bars, corn and palms fibres were prepared to obtain fibres of length less than 5 mm. The fibre materials were mixed by carbon, barium sulfate, silica, metallic powders and phenol formaldehyde. The proposed composites were pressed in the die at 105°C temperature. The produced specimens were subjected to machining processes to obtain the cylindrical form of 8 mm diameter. Experiments were carried out using test rig designed and manufactured to measure both friction and wear. It consists of a rotating hollow flat disc made of carbon steel, with an outside diameter of 250 mm and 16 mm thickness. The experiments investigated the effect of agriculture fibre wastes (corn, sugar bars, and palms fibres) on friction coefficient and wear. Wear mechanisms of the proposed composites were characterized by scanning electronic microscopy. The tribological properties of the proposed composites materials were compared to three commercial brake linings. Based on the experimental results it was found that, addition of agriculture fibre wastes (corn, sugar bars, and palms fibres) to composites materials increased friction coefficient and decreased wear. Friction coefficient slightly increased, while wear drastically decreased with increasing fibres content. The maximum friction value (0.58) was obtained by composites containing 30 wt.% iron and 25 wt.% sugar bar fibres. The corn fibres were more compatible with aluminum powder where it gave the highest friction coefficient and relatively lower wear compared to other composites. Wear resistance of the tested composites containing bunches and aluminum represented the lowest values among composites containing corn and bunches fibres. The lowest wear values were observed for composites containing 25 wt.% corn fibres and 30 wt.% aluminum and composites containing 20-25 wt.% sugar bar fibres. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Farag H.K.,National Research Center of Egypt | Hegab K.H.,National Research Center of Egypt | Hegab K.H.,Gazan University | Zein El Abedin S.,National Research Center of Egypt | Zein El Abedin S.,Clausthal University of Technology
Journal of Materials Science | Year: 2011

Zirconia and mixed zirconia/titania were synthesized in two different ionic liquids, namely, 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl) amide ([BMP]TFSA) and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) amide ([EMIm]TFSA) using sol-gel methods. The synthesized oxides were characterized by means of X-ray diffraction, scanning electron microscopy with energy dispersive X-ray (SEM-EDX)), thermogravimetric and differential thermal analyses (TGA-DTA). The results show that the as-synthesized ZrO 2 powders obtained either in [BMP]TFSA or in [EMIm]TFSA show amorphous behaviour, and calcination at 500 °C yields t-ZrO 2 which is subject to further phase transformation to m-ZrO 2 at 1000 °C. The type of the ionic liquid influences the morphology of the synthesized zirconia as the sample obtained from [BMP]TFSA showed a porous morphology with very fine particles in the nanometer regime, whereas micro-rods were obtained from [EMIm]TFSA. ZrO 2-TiO 2 nanorods with an average diameter of about 100 nm were synthesized in [EMIm]TFSA. The presence of zirconia in the mixed oxides stabilizes the anatase phase and elevates the temperature at which the phase transformation to rutile occurs. © 2011 Springer Science+Business Media, LLC.

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