This study aims to assess the effect of adding twisted fins in a triple-tube heat exchanger used for latent heat storage compared with using straight fins and no fins. In the proposed heat exchanger, phase change material (PCM) is placed between the middle annulus while hot water is passed in the inner tube and outer annulus in a counter-current direction, as a superior method to melt the PCM and store the thermal energy. The behavior of the system was assessed regarding the liquid fraction and temperature distributions as well as charging time and energy storage rate. The results indicate the advantages of adding twisted fins compared with those of using straight fins. The effect of several twisted fins was also studied to discover its effectiveness on the melting rate. The results demonstrate that deployment of four twisted fins reduced the melting time by 18% compared with using the same number of straight fins, and 25% compared with the no-fins case considering a similar PCM mass. Moreover, the melting time for the case of using four straight fins was 8.3% lower than that compared with the no-fins case. By raising the fins’ number from two to four and six, the heat storage rate rose 14.2% and 25.4%, respectively. This study presents the effects of novel configurations of fins in PCM-based thermal energy storage to deliver innovative products toward commercialization, which can be manufactured with additive manufacturing.
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This study aims to identify the most important legislatures and legal frameworks pertaining to advertisement for children. It focuses on the western approach, which is characterized by the variety of its perspectives in presenting issues and in identifying problems. However, if studies show that there is a certain awareness about the advertisement impact on children, it is obvious that most of legislatures reject the laws restricting the broadcast advertising spots intended for children under 12 years of age, with the exception of the Swedish and the Canadian province of Quebec experiences, which opted for total ban on advertising spots broadcast messages targeting children. |
Oxidative stress is oxidative damage caused by free radicals and reactive oxygen species (ROS). These ROS can cause oxidative damage to cellular components, including membrane lipids, receptors, enzymes, proteins, and nucleic acids. It would eventually lead to cell apoptosis and the appearance of certain pathological conditions. This work investigates the antioxidant potentials of chamomile extract in vitro by evaluating the extract activity to scavenge 2,2-Diphenyl-1-picrylhydrazyl (DPPH), also in vivo by investigating its effects on oxidative stress-induced rats by assessing the total oxidant status (TOS) and total antioxidant capacity in the radiation exposed rats with and without the treatment with chamomile extract. The results
... Show MoreSKF Dr. Abbas S. Alwan, Dhurgham I. Khudher, INTERNATIONAL JOURNAL OF ENGINEERING SCIENCES & RESEARCH TECHNOLOGY, 2015
This aims tackles the importance of the organizational energy of the hotel organizations that search the success in the business field to penetrate in the whole tourist markets, and to draw the policies and firm rules which must be framed with the administrative strategies that contributed in creativity and achievement the targets besides provide a future vision due to its position among the competitive henceforth achieving the activity. This is what the chapters tackle in the theoretical side. Also many general questions have been arisen to determinate the importance of the research and many other special questions that express the problem of the study. To limit the levels of study alter
... Show MoreObjective: To investigate and prove that aspirin
protects, or at least attenuates amikacin ototoxicity in
humans.
Method: This study was conducted in 60 patients that
completed all
requirements .The patients were divided into two
groups:
• Control group: receive placebo treatment.
• Drug–treated group: They receive aspirin
coated tablets (1.5gm/ day), 500mg 8 hourly.
Both groups had similar aspects regarding the gender,
age and weight. The duration of therapy was 7 days
and dosage of amikacin was 1gm/day (500mg 12
hourly).
Results: Comparison of Audiometry test in
Ear/Nose/Throat (E.N.T.) Department (Pure Tone
Audiometry) at 1000 Hertz (Hz), 2000 Hz, 4000 Hz,
and 8000 Hz showed sig
Color is one of the most important elements involved and contributing mainly to designs and visual works, whether they are fixed or mobile, for internal spaces through what color gives it the possibilities on the physical and intellectual level, if the process is linked to the functional performance or the aesthetic value, which is thus included within the system of processors and basic works in Designing the interior spaces and highlighting the functional and aesthetic aspects of them through the executed designs that are linked to certain techniques and mechanisms. Therefore, they are processed according to the references and pressure structures or the creation and modern dealing with materials and designs to implement operations in hi
... Show MoreMany diseases can produce cardiac overload, of these disease hypertension, valve disease congenital anomaly in addition to many other disease. One of the most common diseases causing left ventricle overload is hypertension. A long term hypertension can cause myocardium hypertrophy leading to changes in the cardiac contractility and reduced efficiency. The investigations were carried out using conventional echocardiography techniques in addition to the tissue Doppler imaging (TDI) from which many noninvasive measurements can be readily obtained. The study has involved the effect of hypertension on the myocardium stiffness index through the measurement of early diastolic filling (E) and the early velocity of lateral mitral annulus (Ea
... Show MorePerceptions of deity have practical effects in a person’s life, especially in his attitudes toward natural things since nature was created, in which man has treated it as something sacred. The Greek philosophers before Plato and Aristotle did not find in them the idea of divinity clear. Rather, they all searched for the first substance or the first cause of existence, and then gave it all the attributes of God from eternity and eternity, and considered it a first reason without which the universe would not have existed. knowledg
This paper addresses the new coloring in the concept of dystopian society as represented by the positive role of one of the characters vs. the passive role of the government and its mutual effect on the people of the society. In addition, it describes how all men in the dystopian society victimize and degrade the other through unlawful acts, like: stealing, rape, and fear, which are the lowest points in a moral decay. However, it offers hope by illustrating a positive sense, as exemplified by the doctor's wife out of Saramago's optimistic view that men may be descended from good women. Accordingly, the paper aims to examine the effect of the government’s role in the lives of the people who have later turned into blind in a dystopi
... Show MoreThis study aims to reveal the role of one of the artificial intelligence (AI) techniques, “ChatGPT,” in improving the educational process by following it as a teaching method for the subject of automatic analysis for students of the Chemistry Department and the subject of computer security for students of the Computer Science Department, from the fourth stage at the College of Education for Pure Science (Ibn Al-Haitham), and its impact on their computational thinking to have a good educational environment. The experimental approach was used, and the research samples were chosen intentionally by the research community. Research tools were prepared, which included a scale for CT that included 12 items and the achievement test in b
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