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
This research aims to clarify and define the most important philosophical and rhetorical concepts to which many philosophical and rhetorical issues refer، since they have an effective role in the diversity and difference of intellectual schools، which are indispensable in proving major dogmatic issues، such as the concept of (existence، being، essence، and authenticity). Existence or Essence in contrast to the consideration of the other concept)، because it is one of the complex concepts and common words that carry different connotations among thinkers.
And from (the rule of judging something is a branch of its perception)، the researchers began to define these concepts، as evidence of the sincerity of perce
... Show MoreAfter the information revolution that occurred in the Western world, and the developments in all fields, especially in the field of education and e-learning, from an integrated system based on the effective employment of information and communication technology in the teaching and learning processes through an environment rich in computer and Internet applications, the community and the learner were able to access information sources and learning at any time and place, in a way that achieves mutual interaction between the elements of the system and the surrounding environment. After the occurrence of the phenomenon of Covid 19, it led to a major interruption in all educational systems that had never happened before, and the disrupt
... Show MoreThe value of culture in its interaction is composed and formulated according to compatible and incompatible roles which view the identity that adopts that formation although it is in most cases perceived and declared. The attraction and difference characteristic might be implied within subjective and procedural meaning through which it seeks to make the identity mobile subject to identity- shaping cultural causes implying the conflicts that take the shape and culture of real time. As for the end of the twentieth century and afterward where the concepts of hegemony, globalization, cultural invasion, colonial and imperial culture, all these causes made the cultural identity concept appear on the surface of the critical studies as a
... Show MoreThe research in the linguistic structures of the historians Al-Yaqoubi is considered a model of the important topics in historical studies in general, given its importance in the lives of peoples due to its connotations and meanings that summarize interpretation, clarification, and prolonged speech, as it includes life meanings with many dimensions, these structures have been used in historical incidents Important, and throughout the different ages, as it can be used to support an opinion, solve problems, prove evidence, increase wisdom, and it needs rich life experiences, and a sound language, to use it, and needs a wide absorptive capacity for the recipient, the research included linguistic structures in the achievement of science , Lingu
... Show MoreAbstract Introduction: Aphthous stomatitis is a recurring oral ulceration condition that affects a significant proportion of the population. While several factors have been proposed to contribute to its occurrence, the link between caffeine consumption, anxiety levels, and the development of aphthous stomatitis remains unknown. This survey-based study aimed to understand the association between coffee, anxiety, and the development of aphthous stomatitis in this specific demographic, which can provide useful insights for medical management as well as preventive strategies. Material and methods: A structured online questionnaire was distributed via various social media platforms targeting a sample of the Armenian population. The quest
... Show MoreThis study aims to know the extent of the impact of Strategic Leadership as an independent variable in Strategic Learning as a dependent variable to help the senior leadership in Anbar University to take the right decisions to develop Strategic Learning programs in light of the circumstances of the Covid-19 and the sudden decisions adopted by the university to switch to E-learning and to blend. The survey was conducted by distributing a questionnaire that was adopted as a primary tool in data collection from the study sample represented by the university's senior leaders, An intentional random sample of (105) was selected from our community of (127), the data were analyzed by (SPSS) Depe
... Show MoreThe novels that we have addressed in the research, Including those with the ideological and political ideology, It's carry a negative image for the Kurds without any attempt to understand, empathy and the separation between politics and the people, The novels were deformation of the image, Like tongue of the former authority which speaks their ideas, Such as (Freedom heads bagged, Happy sorrows Tuesdays for Jassim Alrassif, and Under the dogs skies for Salah Salah). The rest of novels (Life is a moment for Salam Ibrahim, The country night for Jassim Halawi, The rib for Hameed Aleqabi). These are novels contained a scene carries a negative image among many other social images, some positive, and can be described as neutral novels. We can
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