The reaction paths of the C-C and C-H bond cleavage in the anthracene and phenanthrene aromatic molecules are studied by applying the ab-initio DFT method. It is found that the C-C bond cleavage proceeds via a singlet aromatic transition state, compelled through a disrotatoric ring opening reaction. A suprafacial H atom shift follows the transition state, leading to the formation of a methylene -CH2 and an acetylenic or allenic moiety. The calculated activation energies for anthracene range from 158.81-208.90 kcal/mol and the reaction energies from 96.106-156.976 kcal/mol. For phenanthrene, the energy values are 157.39-202.34 kcal/mol and 62.639-182.423 kcal/mol, respectively. For the C-H cleavage reactions, the calculated reaction energies for all C-H bonds in both molecules are almost similar, 116-117 kcal/mol. The activation energy values for anthracene and phenanthreneare 149.75-161.27 and 161.24-163.00 kcal/mol, respectively.
The main objective and primary concern to every investor not only to achieve a greater return on his or her investments, but also to create the largest possible value of these investments the, researchers and those interested in the field of investment and financial analysis try to develop standards for performance valuation is guided through the  
... Show MoreThe research aims to identify the digital repository of the University of Baghdad, explain its features, how to register, explaining the mechanism for adding and retrieving research. In addition to identifying the number of people registered in and the number of intellectual outputs stored in it. The descriptive approach and survey methods were adopted by visiting the repository's website and the websites of the University of Baghdad's formations during the period (1-6/4/2024). The theoretical framework included an explanation of the concept of the digital repository, the importance of repositories, their features, and types, with reference to models of Iraqi, Arab, and foreign university digital repositories. The practical framework of the
... Show MoreThe modern textual study researched the textuality of the texts and specified for that seven well-known standards, relying in all of that on the main elements of the text (the speaker, the text, and the recipient). This study was to investigate the textuality of philology, and the jurisprudence of the science of the text.
Recently the use of nanofluids represents very important materials. They are used in different branches like medicine, engineering, power, heat transfer, etc. The stability of nanofluids is an important factor to improve the performance of nanofluids with good results. In this research two types of nanoparticles, TiO2 (titanium oxide) and γ-Al2O3 (gamma aluminum oxide) were used with base fluid water. Two-step method were used to prepare the nanofluids. One concentration 0.003 vol. %, the nanoparticles were examined. Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM) and X-ray diffraction (XRD) were used to accomplish these tests. The stability of the two types of nanofluids is measured by
... Show MoreJob stress is considered one of the most important obstacles that may appear in the work field. In order to deal with the obstacles and challenges , the idea to deal with job stress has come to address job stress as one of the most important trends that enable organizations to face those challenges through focusing on the role of job stress and the organizational climate of the organization.
The research deals with two variables: the job stress as an independent variable, and the organizational climate as a dependent one. Each variable includes five sub-dimensions. These dimensions have been involved in an interaction to form
... Show MoreBackground: Prolonged use of low-dose estrogen ''20 micrograms or less" Combined oral contraceptive pill (that have estrogen and progesterone steroid hormone) had an effect on bone turnover .Bone mineral density is used in clinical medicine as an indirect indicator of osteoporosis and fracture risk. The aim of the study: The aim of this study was to investigate the effect of low dose oral contraceptive pill on the cortical thickness (in millimeter) and bone mineral density at the mandibular cortex of mental and gonial regions in Hounsfield unit(HU) using spiral computed tomography. Material and method: This prospective study was conducted on computed tomographic image of 100 women aged between (20-40) years .The collected sample includes
... Show MoreThis paper critically looks at the studies that investigated the Social Network Sites in the Arab region asking whether they made a practical addition to the field of information and communication sciences or not. The study tried to lift the ambiguity of the variety of names, as well as the most important theoretical and methodological approaches used by these studies highlighting its scientific limitations. The research discussed the most important concepts used by these studies such as Interactivity, Citizen Journalism, Public Sphere, and Social Capital and showed the problems of using them because each concept comes out of a specific view to these websites. The importation of these concepts from a cultural and social context to an Ara
... Show MoreGenerally, the academic facilities necessitate specific criteria to be under the regional standards such as creative leaders, and a positive climates that induce to create an organizational culture within the academic institution. Consequently, these variables promote to improve the educational and administrative performance pursuing to achieve the general objectives. Thus, the current research aims to explore the level of privileged organizational culture among Baghdad University Colleges, explore the administrative creativity of deans and their assistants in addition to identify the relationship between them. The researchers prepared two instruments which were distributed among (70) individual of the targeted sample to collect the requ
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