The present study reports the effect of temperature and liquid hourly space velocity (LHSV) on the cumene cracking reaction rate and selectivity by using a laboratory continuous flow unit with fixed bed reactor operating at atmospheric pressure. The prepared HX zeolite was made from Iraqi kaolin with good crystallinity .The activity and selectivity of prepared HX-zeolite was compared with standard HY zeolite and HX zeolite catalysts in the temperature range of 673-823K and LHSV of 0.7-2.5 h-1 . It was found that the cumene conversion increases with increasing temperature and decreasing LHSV at 823K and LHSV of 0.7 h-1 the conversions 65.32, 42.88 and 59.42 mol% for HY, HX and prepared HX catalysts respectively and at LHSV of 2.5 h-1 and the same temperature the conversions decrease to 29.24, 12.53 and 22.89 mol%, respectively .It also found that the benzene yield increases with increasing temperature at 823K and LHSV of 0.7 h-1 the benzene yields were 58.79, 38.56 and 54.56 mol% for HY zeolite , HX zeolite and prepared HX zeolite, respectively and the selectivity to benzene is nearly constant over the studied temperatures range. The kinetics of cumene cracking ( the kinetics parametersrate constant )and activation energy are used in this study to characterize differences between various catalysts. The reaction was found to be first order with activation energy equal to 78.58 , 89.10 and 97.77 kJ/mol for HY, prepared HX and HX , respectively
The current research aims to find out (the effectiveness of teaching TRIZ theory in the expressive performance and the development of creative thinking among preparatory school students)
To achieve this, the researcher adopted on an experimental design is located in women with partial seizure experimental designs field in order to achieve the goals of the research, has sample consisted of two divisions seminars Mentzmtin in junior high school Diyala for Boys, and divided the sample of (60) called on the two groups, the first pilot of ( 30) student, and the other officer and number (30), student, and studied researchers experimental group theory TRIZ, while he studied the officer in the traditional manner, the researcher conducted a pa
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This study included estimation of glutathione (GSH) and Malondialdehyde (MDA) levels in the serum of diabetic patients type II who are treated with a polyherbs mixture (Nigella sativa, Trigonella foenum-graeum, Cyperus rotundus and Teucrium polium) for three months of treatments. Seventy samples of diabetic patients Type II male and females with age about (35-60) years were taken including 44 samples for group one (24 male, 20 female) who used herbs accompanied with chemical treatment (drugs) and 26 samples for the second group (13male and 13 female) who used herbs only. These groups were compared with 60 samples obtained from healthy persons (29 male, 31 female) at the same age of patients as a control group. Effect of age and treatment fo
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The problem of research was to identify after the use of cost technology based on specifications in the validity of determining and measuring the costs of the implementation of contracting, by applying to al-Mansour General Construction Contracting Company as an appropriate alternative to the traditional costing system currently adopted, which is characterized by many shortcomings and weaknesses Which has been reflected in the validity and integrity of the calculations. To solve this problem, the research was based on the premise that: (The application of cost technology based on specifications will result in calculating the cost of the product according to the specification required by the customer, to meet his wishes properly and witho
... Show MoreIn light of the corona pandemic, educational institutions have moved to learning and teaching via the Internet and e-learning ,and this is considered a turning point in course of higher education in Iraq in particular and education in general, which generated a great challenge for educational institutions to achieve the highest possible levels in practices and processes to reach the highest quality of their outputs from graduate students to the labor market that auditing performance by adopting e-learning standards is one of the effective tools that help the management of educational institutions by providing information on the ex
... Show MoreThis contribution provides an atomistic understanding into the impact of W, Nb, and Mo co-substitution at Hf-site of cubic HfO2 lattice to produce Hf1−xTMxO2 system at x = 25%. The calculations have been performed under the framework of density functional theory supported by Habbured parameter (DFT+U). Structural analysis demonstrates that the recorded lattice constants is in good coherence with the previously published results. For the lattice parameters, contraction by 1.33% comparing with the host system has been reported. Furthermore, the doping effect of TM on the band gap leads to its reduction in the resulting Hf0.75TM0.25O2 configurations. The partial density of states (PDOS) indicate that hybridization through localized electroni
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