Different solvents (light naphtha, n-heptane, and n-hexane) are used to treat Iraqi Atmospheric oil residue by the deasphalting process. Oil residue from Al-Dura refinery with specific gravity 0.9705, API 14.9, and 0.5 wt. % sulfur content was used. Deasphalting oil (DAO) was examined on a laboratory scale by using solvents with different operation conditions (temperature, concentration of solvent, solvent to oil ratio, and duration time). This study investigates the effects of these parameters on asphaltene yield. The results show that an increase in temperature for all solvents increases the extraction of asphaltene yield. The higher reduction in asphaltene content is obtained with hexane solvent at operating conditions of (90 °C, 4/1

In this study, a mathematical model is presented to study the chemisorption of two interacting atoms on solid surface in the presence of laser field. Our mathematical model is based on the occupation numbers formula that depends on the laser field which we derived according to Anderson model for single atom adsorbed on solid surface. Occupation numbers formula and chemisorption energy formula are derived for two interacting atoms (as a diatomic molecule) as they approach to the surface taking into account the correlation effects on each atom and between atoms. This model is characterized by obvious dependence of all relations on the system variables and the laser field characteristics which gives precise description for the molecule –

 The study is dealing with an application reengineering process clean solar cells in the Ministry of electricity,  as aimed at the possibility of the applicability and impact of re-engineering to achieve the level of performance of the Ministry's operations, with the application of the cleaning process  solar cells, developed, improved and found a correlation, statistically significant effect between variable re-engineering and performance as well as the application of process reengineering clean solar cells:1- Before the re-engineering process the total time for cleaning up and solar cell 20 minutes and number of columns performed per day 24 columns and total  columns750 which were completed per month that re

The waste sorting and recycling plant in the district of al- Mahmudiya (Yusufiya) is the only laboratory in Baghdad governorate. It is the only one in Iraq that collects and recycles waste. After sorting, we have packages of raw materials (aluminum cans, glass bottles, plastic bottles, Nylon bags) as well as natural fertilizers (food residues and others) and a sanitary landfill with specifications that meet international standards; However, the absence of a structure for the management of the plant (manager, assistant manager, accountant, etc.) in addition to the non-supply of waste on a daily and continuous basis and the lack of cooperation of the Municipality of Baghdad with the management of the plant led to delay in the work

The solidification process in a multi-tube latent heat energy system is affected by the natural convection and the arrangement of heat exchanger tubes, which changes the buoyancy effect as well. In the current work, the effect of the arrangement of the tubes in a multi-tube heat exchanger was examined during the solidification process with the focus on the natural convection effects inside the phase change material (PCM). The behavior of the system was numerically analyzed using liquid fraction and energy released, as well as temperature, velocity and streamline profiles for different studied cases. The arrangement of the tubes, considering seven pipes in the symmetrical condition, are assumed at different positions in the system, i

This study aimed at highlighting the role of small and medium enterprises in bringing about economic development in Jordan. The study examined the impact of the number, size of investment and the number of jobs provided by these enterprises on the rate of growth in gross domestic product (GDP) as an indicator for economic development. To achieve its objectives, the study adopted descriptive and quantitative analysis. A linear multi regression model was developed with a growth rate of GDP as dependent variable and the number of institutions, size of investment, and the number of job opportunities as independent variables. The study concluded that each increase by one small or medium enterprise lead to an increase in the rate of gr