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Polyethylene (PE) belongs among the most widely used polymers in many industrial applications, such as in building, packaging or transport industry. Qatar is one of the largest producers of PE in the world. Composite laminates consisting of PE and metal materials, such as aluminum (Al) lead to an improvement of various mechanical and physical properties necessary for special applications in building industry. Aluminum composite panel (ACP) represents type of flat panel that consists of two thin aluminum sheets bonded to a non-aluminum core, often made from PE. ACPs are frequently used for external cladding or facades of buildings. The main problem relates the adhesion between both materials. In this research work the improvement of adhesion properties of composite laminates prepared from PE and Al using plasma treatment was investigated. This surface treatment led to the significantly increase of peel strength of PE-Al adhesive joints.

Several approaches were tried in order to develop an electrochemical route for producing high purity silicon from molten salts. SiO2, K2SiF6 and metallurgical silicon were used as the source of silicon. Molten electrolytes based on chloride (CaCl2-NaCl) and fluoride (LiF-KF) at temperatures from 550 – 900 °C were used. Transient electrochemical techniques were used to study the electrochemical behaviour of dissolved silicon species. Electrolysis experiments were carried out to deposit silicon.

Proceedings of the TMS Middle East Mediterranean Materials Congress on Energy and Infrastructure Systems (MEMA 2015) -- JAN 11-14, 2015 -- Doha, QATAR, WOS: 000380568300046, Low-dimensional nanostructured materials show large variation in their thermal transport properties. Here, we investigate the influence of core-shell architecture on nanowire ( NW) thermal conductivity using molecular dynamics with Tersoff potentials Si-Ge, to design structures with desired thermal conductivity for thermoelectric device applications. To explore the parameter space, we have calculated thermal conductivity values of Ge/Si core-shell NWs having different lengths, cross-section sizes and Ge concentrations at several temperatures. We have found that ( 1) increasing the cross-sectional area of pure Si NW causes an increase in thermal conductivity ( 2) increasing the Ge core size in the Ge/Si structure results in a decrease in the thermal conductivity values at 300. ( 3) there is no significant variation in the thermal conductivity of Si NW for temperature values larger than 300. ( 4) the predicted thermal conductivity around 10 W m(-1)K(-1) is still larger than the value convenient for thermoelectric applications.