The aim of this study was to investigate the effect of operating variables on, the percentage of removed sludge (PSR) obtained during re-refining of 15W-40 Al-Durra spent lubricant by solvent extraction-flocculation treatment method. Binary solvents were used such as, Heavy Naphtha (H.N.): MEK (N:MEK), H.N. : n-Butanol (N:n-But), and H.N. : Iso-Butanol (N:Iso:But). The studied variables were mixing speed (300-900, rpm), mixing time (15-60, min), and operating temperature (2540, oC). This study showed that the studied operating variables have effects where, increasing the mixing time up to 45 min for H.N.: MEK, H.N.: n-Butanol and 30 min for H.N.: Iso-Butanol increased the PSR, after that percentage was decreased; increasing the mixing speed for all the studied solvents up to 700 rpm increased the PSR, after that the percentage was decreased, while increasing the operating temperature decreased the PSR for all the solvents. This study has resulted in reasonably accurate multivariate process correlation that relates the removed sludge percentage to the process variables. The determination coefficients (
The construction sector in Iraq has faced many challenges. One of the major challenges is the lack of productivity of laborers who are working construction sites. Although research studies have been conducted to investigate, explore, and identify factors influencing labor productivity in the Middle-east region, the lack of such research studies to address these challenges in Iraq. This motivates the researcher to explore and identify the key factors affecting labor productivity in construction sites across different organizational structures (Matrix, Projectized, and functional). A survey questionnaire has been conducted using Delphi technique in order to achieve a concrete and reliab
The present paper addresses cultivation of Chlorella vulgaris microalgae using airlift photobioreactor that sparged with 5% CO2/air. The experimental data were compared with that obtained from bioreactor aerated with air and unsparged bioreactor. The results showed that the concentration of biomass is 0.36 g l-1 in sparged bioreactor with CO2/air, while, the concentration of biomass reached to 0.069 g l-1 in the unsparged bioreactor. They showed also that aerated bioreactor with CO2/air gives more biomass production even the bioreactor was aerated with air. This study proved that application of sparging system for cultivation of Chlorella vulgaris microalgae using either CO2/air mixture or air has a significant growth rate, since the biorea
... Show MoreThe fatty acid composition in the seed and flower of Ligustrun lucidum and olive oil was studied by Gas Chromatography. Results showed that the main components of seed oil were Palmitic (C16:0) 5,893% ,Palmitolic acid (C16:1)0,398%, Steaeic (C18:0)2,911% ,Oleic (C18:1)74,984%,Linoleic (C18:2) 12,959%,and Linolenic (C18:3) 0,997%. The proportion of unsaturated fatty acid was above 89,338%, so the seed oil of L. lucidum ait belonged to unsaturated oil which possessed promising application. The components of flower oil were Palmitic (C16:0) 65,674% ,Palmitolic acid (C16:1)6,516%, Steaeic (C18:0)2,641% ,Oleic (C18:1)14,707%,Linoleic (C18:2) 3,113%,and Linolenic (C18:3) 2,70%. The proportion of unsaturated fatty acid and saturated fatty acid wa
... Show MoreIn this work the interaction of plasma jet with water and hydrogen peroxide liquids used for assisted teeth bleaching by plasma jet had been study. A homemade plasma jet system was used. The plasma jet supply by 15 W electrical power generated by high voltage power supply of 9.6 kV peak to peak and frequency of 33 kHz .this power supply generate high electric field on electrodes that would be enough to ionize the argon gas. Some important agents were study such as the effect of the Ar gas flow rates on the length of the plasma jet, the influence of plasma jet on some properties of water and two hydrogen peroxide concentrations 25 % and 30 % like pH, conductivity and liquid temperature for different exposure time. The liquids temperature
... Show MoreThe Shiite religious authority in Iraq has played an active and vital role over its long history in promoting values of tolerance, rejecting extremism, advocating unity and confronting external challenges. This role has increased significantly after 2003 as a result of the great challenges that have passed in Iraq. Despite its clear policy of non-interference in political matters, except in cases of necessity, but the great role it played in maintaining national unity and advocating the rejection of extremism and sectarianism has made it a necessary need in Iraq to confront any deviations, dispersions or threats that affect society and the state. Therefore, its role in the process of reform was prominent on the political level by calling
... Show MoreThe research in the variables of the political process and government stability tried to show the impact of the political process on political stability first, and then on government stability second, given that the political process that was established in 2005 was aimed at achieving legitimacy, and its most prominent tools are elections, leading to achieving political stability, including government stability. The issue of governmental stability is one of the important issues in Iraq, but it has not been achieved, as a result of several factors, including problems in political action, as the political process has not succeeded in leading Iraq to stability.
The operation of production planning is a difficult operation and it's required High effect and large time especially it is dynamic activity which it's basic variables change in continuous with the time, for this reason it needs using one of the operation research manner (Dynamic programming) which has a force in the decision making process in the planning and control on the production and its direct affect on the cost of production operation and control on the inventory.
The economic development and intense competition may make economic units neglected the social aspect as a service workers and the environment, the community and focus on the economic side and achieve profitability only, which puts it in a position of accountability of trade unions and bodies, environment, health, civil society organizations and the focus of many studies accounting in order to clarify social activities and disclosed in the financial statements, increasing pressure from multiple parties calling for governments to issue laws and regulations oblige economic units to disclose complete and accurate information in a timely manner for all social activities and be subj
... Show MoreExtracorporeal Shock Wave Lithotripsy (ESWL) is the most commonplace remedy for kidney stone. Shock waves from outside the body frame are centered at a kidney stone inflicting the stone to fragment. The success of the (ESWL) treatment is based on some variables such as age, sex, stone quantity stone period and so on. Thus, the prediction the success of remedy by this method is so important for professionals to make a decision to continue using (ESWL) or tousing another remedy technique. In this study, a prediction system for (ESWL) treatment by used three techniques of mixing classifiers, which is Product Rule (PR), Neural Network (NN) and the proposed classifier called Nested Combined Classi
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