Journal of King Abdulaziz University-science, 2008

High efficiency design for single crystal growth from melt based on Bridgman technique is constructed locally and used for growing TlInTe2 crystals. Measurements of Hall coefficient and DC electrical conductivity covering a temperature range from 158 to 473 K were conducted. The investigated samples have P-Type conductivity with RH of 2.3 × 109 cm3/coul. at room temperature and carrier concentrations as 2.81×109 cm-3. Energy gap ?Eg and ionization energy ?Ea were estimated as 0.72 eV and 0.113 eV, respectively. The diffusion coefficient, diffusion length, as well as relaxation time were evaluated, and the scattering mechanism of charge carrier was checked.

In this research, the microwave energy was used to modify the physicochemical properties of ‎ilmenite surface for improvement of ilmenite floatability. The XPS analysis showed that ‎microwave irradiation oxidizes the Fe2+ ions to Fe3+ ones; and the relative content of Fe3+ on the ‎surface of ilmenite increases from 48.5% to 66%. This oxidation process decreases the ilmenite ‎zeta potential; as its PZC (point of zero charge) was changed from pH=5.4 to pH=3.0. The ‎increase of Fe3+ ions increases the chemisorption of oleate ions on the surface of ilmenite; and ‎results in the formation of more insoluble ferric iron oleate. The maximum adsorption of oleate ‎ions occurs at a pH range of 6-7. After microwave irradiation the measured contact angle of ‎ilmenite increases from 91 to 96 degrees. After oleate adsorption, the surface zeta potential of ‎non-irradiated and irradiated ilmenite is obtained -66.3 mV and -78.1 mV, respectively. Thus, the ‎changes in the physicochemical properties of...

2015

2015

Fluid Mechanics Textbook (in Arabic), 2010

2015

2022

2015

2017

Givers of foreign Audit about Social Responsibility of Profit Organization. The recent time is charcterstically with big economic Organization activities, because there are many transactions between these Organizations and different financial markets development techniques. This encourgage business men to increase their efforts for investment in these markets. Because the Accounting is in general terms it represents a language of these Unions Activities and translate them in to fact numbers, for that there is need for Accounting recording for certain of these Organizations behavior and their harmonization with their Objectives. In this respect the Audit function comes to check the activities of these Organizations and their social responsibilities and whether they are suitable with social considerations or not. ‫المجلد‬ 51 ‫العدد‬ 15 9002-290-‫المجلد‬ 51 ‫العدد‬ 15 9002