يثير موضوع العلاقات بين روسيا_والولايات المتحدة ، في الجانبين السياسي والاقتصادي، اهمية علمية وعملية، كونه يناقش موضوع لا يمكن لاي منطقة او اقليم في العالم ان يكون بمنأى عنه، بحكم ما تتمتع به روسيا والولايات المتحدة من امكانات وموارد قوة ان روسيا وريث الاتحاد السوفيتي، تملك من الامكانات السياسية والعسكرية والاقتصادية والحضارية ما يجعلها عامل مؤثر دوليا، والامر اكثر منه المتعلق بالولايات المتحدة، فهي القوة العظمى الرئيسية في عالم اليوم، منذ تفكك الاتحاد السوفيتي.والاكثر منه، ان كل من القوتين لهما مصالح ولهما سياساتهما تجاه منطقة الشرق الأوسط عامة، وهو م
Experimental investigation of the mass transfer characteristics of – water system falling film in spiral tubes has been done. Several experiments were performed on the average mass transfer liquid film
Several semi-empirical modified equations for the pore size and porosity had been suggested depending on the parameters affecting them for sphere particles of mono, binary and ternary packing systems. The parameters affecting the pore size were found to be the particle diameter, the porosity of the bed and the permeability to fluid flow. The parameters affecting the porosity in the packed bed of sphere packing are the particle and bed diameters. Several types of packing materials with different sizes have been used in the packed bed, and each had been studied separately.
The present work is concerned with constructing a computer program to simulate the analysis of multi-component, multistage continuous reactive distillation processes.The rigorous method was used to build computer programs simulation for non ideal mixtures.
Carboxy methyl cellulose, two anionic surfactants, Sodium stearate,Sodium lauryl sulfate and suspended clay as drag reducers have been investigated in this work, to reduce the frictional resistance and to save pumping power for turbulent pipe flow. The turbulent mode was produced via a positive displacement gear pump to avoid mechanical degradation of additives chains during the experimental period.
Computational fluid dynamics (CFD) simulation, deals with the solution of fluid dynamic equations on digital computers, requiring relatively few restrictive assumptions and thus giving a complete description of the hydrodynamics of bubble columns. This detailed predicted flow field gives an accurate insight to the fluid behaviors.3D simulation computational fluid dynamics (CFD) is applied using ANSYS-CFX Euler-Euler model to measure the hydrodynamic of an airlift reactor, and comparing with experimental data of Baten et. al., (1999).
The prediction of accurate values of saturated enthalpy of vapor is very important in process design calculations and other industrial applications. Experimental measurements of saturated enthalpy of vapor are not easy to perform. So in order to obtain accurate saturated enthalpy of vapor, attention has been turned to calculate them using equations of state.
Steganography is the art of information hiding in ways that prevent its detection. A message in cipher text may raise suspision, while an invisible message will not. Digital steganography uses a host data or message, known as a ''container'' or ''cover'' to hide another data or message called ''secret'' in it. An Image in audio steganography system had been proposed in this thesis in order to embed a secret image data in audio data.
Two types of synthetic crystalline zeolites have been used as supports for noble-metal catalysts, namely HZSM-5 and H-Mordenite with SiO ratios of 90 and 40 respectively. The cations, Barium and Strontium zeolite forms were prepared by twice repeated ion-exchange with appropriate chloride solution of 3 normality at pH 7.2 and 50oC. The modified zeolites were dried at 110oC and calcined at 450o C by step wise temperature increase. The ion-exchange by strontium was more effective than by Barium cation. While the ability of H-replacement at HMOR was higher than in case of HZSM-5.
This research deals with experimental study of the rheological behavior of polymer solutions. All polymers studied in this work are water soluble and used in industries as rheology control additives (rheology modifiers), these are: XC-polymer, Carboxymethyl cellulose (two types),Hydroxyethyl cellulose and Polyvinyl alcohol. The rheological properties of these polymer solutions was investigated using a Couette coaxial cylinder rotational viscometer ( Fann model 35A ), by measuring shear stresses versus shear rates (i.e. the flow curve).