The liver (hepatic) is one of the largest glands or organs of the digestive system in the body of living organisms, including rodents, take the squirrel in this study for example. The study and the collection of sources emerged to be put into the hands of those, especially those interested in histological studies, including junior or professionals and veterinarians, knowledge of the stains used in the research and their final results.

New types of hydrodesulfurization (HDS) catalyst Re-Ni-Mo/ γ-Al₂O₃ was prepared and tested separately with two prepared conventional HDS catalysts (Ni-Mo/ γ-Al₂O₃ and Co-Mo//γ-Al₂O₃) by using a pilot plant hydrotreatment unit. Activities of three prepared hydrodesulfurization catalysts were examined in hydrodesulfurization (HDS) of atmospheric gas oil at different temperatures 275 to 350 °C and LHSV 1 to 4 h^-1, the reactions conducted under constant pressure 40 bar and H₂/HC ratio 500 ml/ml .Moreover, the hydrogenation of aromatic (HAD) in gas oil has been studied. HDS was much improved by adding promoter Re to the Ni-Mo/Al₂O₃

     This aims tackles the importance of the organizational energy of the hotel organizations that search the success in the business field to penetrate in the whole tourist markets, and to draw the policies and firm rules which must be framed with the administrative strategies that contributed in creativity and achievement the targets besides provide a future vision due to its position among the competitive henceforth achieving the activity. This is what the chapters tackle in the theoretical side. Also many general questions have been arisen to determinate the importance of the research and many other special questions that express the problem of the study. To limit the levels of study alter