The present study explores numerically the energy storage and energy regeneration during Melting and Solidification processes in Phase Change Materials (PCM) used in Latent Heat Thermal Energy Storage (LHTES) systems. Transient two-dimensional (2-D) conduction heat transfer equations with phase change have been solved utilizing the Explicit Finite Difference Method (FDM) and Grid Generation technique. A Fortran computer program was built to solve the problem. The study included four different Paraffin's. The effects of container geometrical shape, which included cylindrical and square sections of the same volume and heat transfer area, the container volume or mass of PCM, variation of mass flow rate of heat transfer fluid (HTF), and temperatures difference between PCM and HTF were all investigated. Results showed that the PCMs in a cylindrical container melt and solidify quicker than the square container. The increase in mass flow rate and/or temperature difference decreases the time required for complete phase change. Paraffin's solidify quicker than they melt and store more energy than they release
In this work, electron number density calculated using Matlab program code with the writing algorithm of the program. Electron density was calculated using Anisimov model in a vacuum environment. The effect of spatial coordinates on the electron density was investigated in this study. It was found that the Z axis distance direction affects the electron number density (ne). There are many processes such as excitation; ionization and recombination within the plasma that possible affect the density of electrons. The results show that as Z axis distance increases electron number density decreases because of the recombination of electrons and ions at large distances from the target and the loss of thermal energy of the electrons in
... Show MoreThe study aims to build a model that revolves around the main question of the role of strategic agility (SA) in enhancing organizational excellence (OE). For the purpose of achieving OE and to determine the extent of interest and knowledge of managers at the Midwest Refineries Company (MRC) on the theoretical and practical implications, and on the performance foundations of these two vital variables with the aim of continuous improvement. A questionnaire was used and distributed to a random sample of 54 managers in this important energy production company. The study followed the descriptive analytical approach to answer the questions raised. The study model and dimensions were built according to reference models, most notably the mo
... Show MoreSomerset Maugham is known mainly as a novelist . This paper presents Maugham the dramatist . Many critics have found him a promising dramatist . He has written 30 plays , then he turns his back upon the theater and writes his autobiographical and most successful novel Of Human Bondage ( 1915) .
Maugham's writing is clear , precise , and simple . He is described as a realist who is keenly aware of human nature , its concentration and frustration . His only tragedy A Man of Honour is a play in 4 acts . This paper concentrates mainly on this play to show Maugham as a dramatist and to show his concept of " honour " .
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... Show MoreEpilepsy is the most common neurological disorder after Alzheimer and other cerebrovascular diseases. Antiepileptic drugs (AED's) are one of the most important methods to prevent epileptic seizers. Antiepileptic drugs can cause damage to the liver which is the largest and most important glandular organ in the body with many other drugs. Carbamazepine (CBZ) is a known anticonvulsant that is widely used and known for a decade, it was used to treat trigeminal neuralgia, bipolar disorder and epilepsy and it can cause hepatotoxicity. In this study female white mice received CBZ suspension at a dose of 20 mg/kg/mouse via gastric gavage for 30 days, tissue samples were collected for scanning electron microscopy. We observed the adverse effects of
... Show MoreThe business environment is witnessing tremendous developments in the field of production and technology, which requires the development of production methods to go in line with these developments and the increasing competition, which has gone beyond the economic aspects to extend to the environmental aspects, as economic units tended to adopt a cleaner production strategy and through what they achieve by producing environmentally friendly products and achieving economic efficiency. Reducing costs, providing a safe and clean environment for workers, and reducing waste from production operations.
The current study aims to identify the effect of guided visualization strategy in developing the visual perception among kindergarteners. The experimental design was used; pre-post test. A total of (32) boy and girl ranging 5 to 6 years old were selected from al-Rabeea’ kindergarten, directorate of al-karkh 2 / Baghdad. The sample divided into equal two group (16) boy and girl of each one. al-Talaqany’s (2016) visual perception skills test among kindergarteners was adopted to collect the required data. The collected data had processed based on (gender, pre-post test, and age). To achieve the objectives of the study; the researcher set up series of sessions that addressed the guided visualization strategy among kindergarteners compose
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