A set of hydro treating experiments are carried out on vacuum gas oil in a trickle bed reactor to study the hydrodesulfurization and hydrodenitrogenation based on two model compounds, carbazole (non-basic nitrogen compound) and acridine (basic nitrogen compound), which are added at 0–200 ppm to the tested oil, and dibenzotiophene is used as a sulfur model compound at 3,000 ppm over commercial CoMo/ Al2O3 and prepared PtMo/Al2O3. The impregnation method is used to prepare (0.5% Pt) PtMo/Al2O3. The basic sites are found to be very small, and the two catalysts exhibit good metal support interaction. In the absence of nitrogen compounds over the tested catalysts in the trickle bed reactor at temperatures of 523 to 573 K, liquid hourly space velocity 1 to 3 hr−1 , and a pressure range of 16 to 20 bar, the results show an increase in conversion from 0.2214 to 0.6748 and 0.2920 to 0.7341 for CoMo and PtMo, respectively, with the increase of temperature, a little positive effect on conversions when pressure increases, and a significant decrease in conversion: 0.6748 to 0.3284 and 0.7341 to 0.3734 for CoMo and PtMo, respectively, when liquid hourly space velocity increases. The results showed a first-order kinetic of Dibenzothiphene (DBT) hydrodesulphurization. The activation energies are 75.399 and 67.983 kJ/mol for hydrodesulphurization of DBT over CoMo and PtMo, respectively.
Background: Non-nutritive sucking habits are common in infants and toddlers. One of the most common non-nutritive sucking habits is pacifier; its prevalence varies from one population to another. This study was conducted to determine the prevalence of pacifier sucking habit among children aged 1-5 years old in Baghdad city and to assess its effect on the occlusion of primary dentition concerning posterior crossbite. Materials and methods: The study was carried out among 1222 children aged 1-5 years old, from which 50 children with continues pacifier sucking habit were chosen to be the study group, compared to 50 children without any sucking habit (control group) matching the study group in age and gender. Children were examined clinically t
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This paper represents a study of the effect of the soil type, the drilling parameters and the drilling tool properties on the dynamic vibrational behavior of the drilling rig and its assessment in the drilling system. So first, an experimental drilling rig was designed and constructed to embrace the numerical work.
The experimental work included implementation of the drill-string in different types of soil with different properties according to the difference in the grains size, at different rotational speeds (RPM), and different weights on bit (WOB) (Thrust force), in a way that allows establishing the charts that correlate the vibration acceleration, the rate of penetration (ROP), and the power
... Show MoreThe approximate solution of a nonlinear parabolic boundary value problem with variable coefficients (NLPBVPVC) is found by using mixed Galekin finite element method (GFEM) in space variable with Crank Nicolson (C-N) scheme in time variable. The problem is reduced to solve a Galerkin nonlinear algebraic system (NLAS), which is solved by applying the predictor and the corrector method (PCM), which transforms the NLAS into a Galerkin linear algebraic system (LAS). This LAS is solved once using the Cholesky technique (CHT) as it appears in the MATLAB package and once again using the General Cholesky Reduction Order Technique (GCHROT), the GCHROT is employed here at first time to play an important role for saving a massive time. Illustrative
... Show MoreBackground: One of the most common problem associated with the used of soft denture lining material is microorganisms and fungal growth especially Candida albicans, which can result in chronic mucosal inflammation. The aim of this study was to evaluate the influence of chlorhexidine diacetate (CDA) salt Incorporation into soft denture lining material on antifungal activity; against Candida albicans, and the amount of chlorhexidine di-acetate salt leached out of soft liner/CDA composite. Furthermore, evaluate shear bond strength and hardness after CDA addition to soft liner Materials and methods: chlorhexidine diacetate salt was added to soft denture lining material at four different concentrations (0.05%, 0.1% and 0.2% by weight). Four hund
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The current phase distinguish by the rapid scientific development, which pushes individuals to have the necessities of scientific and practical life through the proper scientific thinking which contribute to the development of invention and creativity away from memorizing and indoctrination and encouraging individuals to looking for information and then attempting to process and develop these information instead of being a passive receiver. The investment of minds becomes the logical investment in all societies by preparing the citizen to become able to face life changes and its necessities. It is very important to take care of individuals and develop their mental abilities and thinking skills. The constructive strateg
... Show MoreThe main objective of this study is to determine whether the use of He-Ne Laser (632.8 nm wavelength and power 0.5 mW) is an eligible and effective tool to kill or reduce the cell viability of Candida albicans isolated from complete upper dentures. Twenty one swabs were taken from the complete upper dentures. Only six swabs showed positive cultures for C. albicans. The isolate was divided into two groups, group I was not irradiated (control), and group II was irradiated by He-Ne Laser for different periods (10, 15, 20, and 30) min. After irradiation, the results showed a significant reduction in the viable cell count and colonies diameters especially at exposure periods 10 and 15 min. Although the low power He-Ne Laser was not eradicating t
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Background: Determination of local bone mineral density (BMD) with cortical thickness and bone height may offer a comprehensive description of the bone the surgeon will encounter when he or she actually sets the implant. Quantitative computed tomography (CT) (i.e., quantitative interpretation of values derived from Hounsfield units with a suitable calibration procedure) is the modality of choice to determine BMD. The aim of the present clinical study is to determine the local bone density in dental implant recipient sites using computerized tomography. Material and method: The sample consisted of (72) Iraqi patients whom referred to Al-Kharkh General hospital, Spiral CT scan Department for bone quality and quantity assessment after one wee
... Show MoreWill address this research interaction and coordination between fiscal and monetary policies and the impact of this interaction and coordination on economic stability and growth، and how the financial implications of monetary policy may stimulate action monetary policy and treatment side effects and the nature of responsiveness and bounce between procedures both two policies and their impact on the balance of overall economic and explained in the folds of searchjustifications coordination and the extent necessary in order to address the imbalances in economic activity through twinning actions of monetary and fiscal، has embodied this coordination and interaction between policies and their impact m
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The aim of this study was to provide an overall assessment to the efficiency of the Iraq stocks exchanges (ISE) through specifying well –known models .First, Fama's efficient market hypothesis as a contrary concept to the random walk hypothesis, was performed and it has been found that ISE follows the random process, so the price of the shares can't be predicated on the basis of past information. Second,we use a multifactor model, which so named multiple regression, to explore the link between ISE and the main economic indicators. our empirical analysis finds that every weak associations exists between major ISE measures and main economic indicators.
Simple, rapid and sensitive spectrophotometric method was proposed for the analysis of metoclopramide hydrochloride (MPH) in pure form as well as in pharmaceutical tablets. The method is based on the diazotization reaction of MPH with sodium nitrite in hydrochloric acid medium to form diazonium salt, which is coupled with 1-naphthol in sodium hydroxide medium to form azo dye, showing absorption maxima at 550 nm. Beer’s law is obeyed in the concentration range of 0.4 – 18 µg mL-1 of MPH with detection limit 0.5448 µg mL-1. The molar absorptivity and Sandell’s sensitivity are 3.4969 × 104 L mol-1 cm-1 and 0.0101 µg cm-2, respectively. The method was successfully applied to the determination of MPH in pharmaceutical tablets with
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