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
Recently, biometric technologies are used widely due to their improved security that decreases cases of deception and theft. The biometric technologies use physical features and characters in the identification of individuals. The most common biometric technologies are: Iris, voice, fingerprint, handwriting and hand print. In this paper, two biometric recognition technologies are analyzed and compared, which are the iris and sound recognition techniques. The iris recognition technique recognizes persons by analyzing the main patterns in the iris structure, while the sound recognition technique identifies individuals depending on their unique voice characteristics or as called voice print. The comparison results show that the resul
... Show More A series of N- benzoyl - 2 – alkyl -1- ( 2- thio – 1,3,4- thiadiazole -5- yl ) , have been synthesized from DL- α– amino acids , The methyl and sulfon thio ethers of these compounds were also prepared , representative samples of the prepared compounds were characterized from their IR- spectrum and elemental analysis .
Praise be to Allah, Lord of the Worlds, and peace and blessings be upon our master Muhammad and his good and pure family. At the end of this research, we summarize some of the most important findings of our research, namely:
Raising a child properly from childhood leads to integrity in the life of the individual society, and if the young raised bad education, this education will affect itself and society negatively, so on parents and government institutions in any country to take care of children, and Islamic countries Specifically to give the child great attention; he is raised on the Koran and watered from its fountains, and armed with a weapon of morality from a young age, and to understand the biography of Mustafa (peace be upon h
Background: Venous thromboembolism (VTE), comprising deep vein thrombosis (DVT) and pulmonary embolism (PE), presents an extra challenge in the management of patients with cancer, given the increase in morbidity and mortality in having both conditions. Cancer patients are well known to have a high risk of VTE; particularly; those who have had major surgery, chemotherapy and/or hormonal therapy. These groups of patients need to understand the risk factors and the prophylactic measures to prevent developing VTE. This review aims to provide an overview of the literature on cancer patients’ understanding of VTE and their experiences of cancer-associated thrombosis (CAT).
Method: A scoping review wa
... Show Morethe structrual and mechanical properties of thin Ni films of different thicknesses deposited on coring glass substrate using lonbeam sputtering(IBS) technique under vacuum torr have been studied the TEM and electron
Background: Although Electroconvulsive Therapy (ECT) is still regarded as a controversial treatment by some people, it is an important and effective treatment. The practice of ECT is different across the world.
Objectives: to obtain an overview of the electroconvulsive therapy practice in Iraq.
Method: Forty item self administered questionnaire about the attitude and practice of ECT, was sent (by mail or delivered by the researcher) to 73 Iraqi psychiatrists during the period from March to September, 2007.
Results: Half of participants had asked for the patient's consent, and all asked the family for the consent, 72%
... Show MoreThe telecommunications industry has gone through series of development efforts to provide quality services to their consumers. Generally, telecommunication industry provides two main services such as telephony and internet which involved customer registration, billing and payment. However, the challenge confronting telecommunications industry is to meet the customer satisfaction in the billing system such as accuracy, easy to understand and unambiguous billing issue. In order to develop Customer Billing Telephony System,a user experience study is conducted to gather the user requirements. Hence, the CBTS was developed that takes into consideration user’s value experience that provides a support for managing and monitoring billing proce
... Show MoreThis search study the effect of particle size of graphite on the mechanical and thermal properties of epoxy composites, where graphite adopted with particle sizes (45,53,75) ?m, respectively, and the percentages by weight (0,1,3,5,7,9)% for each size of this three particle sizes.Mechanical properties represented by the bending (three-point bending) and through which the conclusion is bending stress and modulus of elasticity, thermal properties were either through thermal conductivity tests.The results showed that the ratio(1%) is the maximum value of bending stress at the three particle size and the (45 ?m) is the maximum.Thermal conductivity result show is the maximum value at ratio (1%) of particle size(53 ?m)
Today’s world confronts various threats from different sources. Similar to deprivation of energy, economic facilities, or political deposition, educational poisoning is one of the dangerous phenomena that result from distorting and corrupting the ethical and educational components of teaching by various material and non – material means.This paper sheds light on the concept of the educational system which is not a mere process of teaching, but rather an endless process of socialization that begins in the family and develops into religious, ethical, scientific and mythological systems, all of which form the cognitive component. It also defines the necessary means by which it is transmitted from one generation into another. The educati
... Show More The study is focused on the modification of the standardized newspaper with natural polymers chitosan and keratin hydrolysate applied on the paper surface from polymer solution. This modification is based particularly on the formation of the complexes between acidic surface groups on cellulose fibers and the natural polymers which improved the mechanical properties of the paper and the positive results which were observed particularly in folding endurance of the newspaper.