المقدمة

تعد السياحة احد مستلزمات الحضارة الحديثة لما تفرزه من آثار ايجابية ودور متميز في دعم الاقتصاد الوطني وتقليل نسبة البطالة وتنشيط الحركة التجارية بين البلدان، اذ لا يمكن ان نتصور وجود بلد متحضر بلا فنادق ولا سياحة وتقديم مختلف السلع والخدمات سياحية التي يمكن ان تسبع الحاجات والرغبات واذواق السياح من خلال  وجود منشآت سياحية تعكس النمط السياحي القائم على اختلاف انواعه

The corrosion of low carbon steel boiler tubes in demi water had been investigated. The purpose of this investigation was to determine the change produced in corrosion behavior of the carbon steel as a result of the specific presence of chloride and copper ions in the water under different temperatures. For low carbon steel experiments, the temperature was taken in three levels (125, 175, and 215°C) under about 27 bar pressure and 1500 rpm in autoclave. Using weight loss technique, the corrosion rate ranges from (85 to 789 gmd) for low carbon steel boiler tubes.

This paper is concerned with finding solutions to free-boundary inverse coefficient problems. Mathematically, we handle a one-dimensional non-homogeneous heat equation subject to initial and boundary conditions as well as non-localized integral observations of zeroth and first-order heat momentum. The direct problem is solved for the temperature distribution and the non-localized integral measurements using the Crank–Nicolson finite difference method. The inverse problem is solved by simultaneously finding the temperature distribution, the time-dependent free-boundary function indicating the location of the moving interface, and the time-wise thermal diffusivity or advection velocities. We reformulate the inverse problem as a non-

Objective: The present study investigates whether the exposure to low-power diode laser induces denaturation in red blood cell (RBC) membrane protein composition, and determines the irradiation time for when denaturation of membrane protein process begins. Background: A low-energy laser has been used extensively in medical applications. Several studies indicated significant positive effects of laser therapy on biological systems. In contrast, other studies reported that laser induced unwanted changes in cell structure and biological systems. The present work studied the effect of irradiation time of low-power diode laser on the structure of membrane proteins of human RBCs. Materials and methods: The RBC suspension was divided into five equa

In the present study, a powder mixture of elements Ti and Ni was mechanically alloyed in a high energy ball mill. Microstructure of the nanosized amorphous milled product in different stages of milling has been characterized by X- ray diffraction, scanning electron microscopy and differential thermal analysis. We found that time of mechanical alloying is more significant to convert all crystalline structure to the amorphous phase. Nanocrystalline phase was achieved as a result of the mechanical alloying process. The results also indicates that the phase transformation and the grain size occurs in these alloys are controlled by ball milling time

This research deals with the effects of welding variables using MIG/MAG spot by using Argon (Ar) gas and CO₂ to show their effect on the mechanical characteristics and microstructure of low alloy steel type DIN15Mo3 and determine the optimum condition for the process of welding ; current & time. The results show the possibility of using CO₂ and also Ar in low alloy steel welding with a little decrease in the shear force of not more than 13% for 4mm thickness and time 2sec. The shear force increased when using Ar instead of CO₂ to be , The shear force reach 36KN when using Ar at 2mm thickness  time of 8 sec and current of 220 Amp. , when used CO₂ instead of Ar d

The different parameters  on  mechanical  and  microstructural  properties  of  aluminium  alloy  6061-T6 Friction  stir-welded  (FSW) joints  were investigated in the  present study. Different welded  specimens were produced by employing variable rotating  speeds and welding speeds. Tensile strength of the produced joints  was tested at room  temperature and the the effecincy was assessed, it was 75% of the base metal at rotational speed 1500 rpm and weld speed 50 mm/min. Hardness of various zones of FSW welds are presented and  analyzed by  means of  brinell hardness number . Besides to thess tests the bending properties  investigat