Due to the potential cost saving and minimal temperature stratification, the energy storage based on phase-change materials (PCMs) can be a reliable approach for decoupling energy demand from immediate supply availability. However, due to their high heat resistance, these materials necessitate the introduction of enhancing additives, such as expanded surfaces and fins, to enable their deployment in more widespread thermal and energy storage applications. This study reports on how circular fins with staggered distribution and variable orientations can be employed for addressing the low thermal response rates in a PCM (Paraffin RT-35) triple-tube heat exchanger consisting of two heat-transfer fluids flow in opposites directions through the inner and the outer tubes. Various configurations, dimensions, and orientations of the circular fins at different flow conditions of the heat-transfer fluid were numerically examined and optimized using an experimentally validated computational fluid-dynamic model. The results show that the melting rate, compared with the base case of finless, can be improved by 88% and the heat charging rate by 34%, when the fin orientation is downward–upward along the left side and the right side of the PCM shell. The results also show that there is a benefit if longer fins with smaller thicknesses are adopted in the vertical direction of the storage unit. This benefit helps natural convection to play a greater role, resulting in higher melting rates. Changing the fins’ dimensions from (thickness × length) 2 × 7.071 mm2 to 0.55 × 25.76 mm2 decreases the melting time by 22% and increases the heat charging rate by 9.6%. This study has also confirmed the importance of selecting the suitable values of Reynolds numbers and the inlet temperatures of the heat-transfer fluid for optimizing the melting enhancement potential of circular fins with downward–upward fin orientations.
Background: Tubal ligation, recognized as a surgical intervention that ensures permanent contraception, has established itself as an option for women seeking a definitive solution for family planning. Objective: To assess the psychosexual implications of tubal ligation in a sample of women in Baghdad, Iraq. Methods: A prospective cohort study was conducted in a teaching hospital for 2 years, from the first of January 2022 to the end of December 2023, in which 203 women who underwent tubal ligation were included. Results: In the present study, we found that 158 (77.8%) had no depression, mild depression presented in 27 (13.3%), and moderate depression in only 15 (7.4%). While 163 (80.3%) of women did not suffer from anxiety, 32 (15.8
... Show MoreParonomasia is a recognized rhetorical device by which poets could play with words that are similar or identical in form but different in meaning. The present study aims to identify paronomasia in Arabic and English. To achieve the aim of the study, a corpus of selected verses chosen from two famous figures in Arabic and English literatures and analyzed thoroughly. The analysis of data under investigation reveals that paronomasia is a crucial aid used by poets to portrait the real world as imaginative. It further shows that the concept of paronomasia in English is not the same as in Arabic. In English, there are echoes of the Arabic jinās, i.e., there are counterpart usages of similar devices, yet English rhetoricians have not defined or c
... Show MorePeriodontitis is a persistent bacterial-causing disease which damages the supporting periodontium of the teeth. The complexity of supporting tissue structure makes the regeneration a challenge for periodontists. Early investigations were focused on discovering therapeutic substitutes that are biocompatible, simple to prepare and economic. This might cause a local release of growth factors that accelerate the healing process of the soft and hard tissue. Recently, platelet-rich fibrin (PRF) has received a wide attention as a biocompatible regenerative material in both dental and medical fields. PRF is a natural fibrin-derived biomaterial, and it is easy to obtain. It can be gotten from individual blood without the use of any external anticoag
... Show MoreThe Caputo definition of fractional derivatives introduces solution to the difficulties appears in the numerical treatment of differential equations due its consistency in differentiating constant functions. In the same time the memory and hereditary behaviors of the time fractional order derivatives (TFODE) still common in all definitions of fractional derivatives. The use of properties of companion matrices appears in reformulating multilevel schemes as generalized two level schemes is employed with the Gerschgorin disc theorems to prove stability condition. Caputo fractional derivatives with finite difference representations is considered. Moreover the effect of using the inverse operator which tr
Animation is an industry that is expanding more quickly than ever. Every child’s favorite activity is watching cartoons. Therefore, it is essential to be cautious of the kinds of cartoon films children and teenagers tend. Because children and teenagers are the target audience for these films. This study aims at exposing a hidden enactment, namely racism, in a well-known cartoon film, Lion King, which has been selected accurately by the researchers because it shapes a set of ideas about black people and constructs prejudiced beliefs in their minds. This study is to answer the inquiry ‘Is the ideology of racism imposed in Lion King? And how?’ The significance of the present paper lies in highlighting the educational function of
... Show MoreThis study explores the semiotic aspects of American slang, specifically focusing on the phenomenon of reduplicative expressions in informal speech. Despite the extensive research on American slang, limited attention has been given to the cultural and mythical meanings embedded within reduplicative expressions. To address this gap, the study investigates how these expressions convey denotative, connotative, and mythical meanings within casual American discourse. The objectives of the study include: 1. To what extent does Barthes’ semiotic model hold potential for application in this study? 2. How are reduplicative slang expressions widely used in everyday American life? 3. To what extent do qualitative and quantitative methods hav
... Show MoreThe study included gross morphology and pollen of plants – which collected during field trips , and dry ones for most specimen preserved with the Iraqi herbaria – related to the genus Lycopus L. , and to identify the unidentified species and rectify the error there in , so according to that the species L. europaeus L. only were specified for the genus . Through this work the varity L. europaeus var. glabrescens Schmidely were found at the first time , and suggested to record anew for Iraq . Pollen were of medium size, and had an ellipsoid shape in the equatorial view , and hexagonal in the polar view. The ecological and soil quality where these genus plants grows were specified , and were geographically distribut
... Show MoreBackground: Lymphomas are group of diseases caused by malignant lymphocytes that accumulate in lymph nodes and caused the characteristics lymphadenopathy. Occasionally, they may spill over into blood or infiltrate organs outside the lymphoid tissue. The major subdivision of lymphomas is into Hodgkin lymphoma and non–Hodgkin lymphoma and this is based on the histologic presence of Reed-Sternberg cells in Hodgkin lymphoma. Salivary immunoglobulin A is the prominent immunoglobulin and is considered to be the main specific defense mechanism in oral cavity. The aim of this study was to determine the level of salivary immunoglobulin A in lymphoma patients before and after chemotherapy treatment. Subjects, materials and methods: The study i
... Show MoreOne of the prominent goals of Metrical Phonology Theory is providing stress of poetry on the syllable-, the foot-, and the phonological word- levels. Analysing poetry is one of the most prominent and controversial issues for the involved number and types of syllables, feet, and meters are stable in poetry compared to other literary texts. The prosodic seeds of the theory have been planted by Firth (1948) in English, while in Arabic يديهارفلا in the second half of the eighth century (A.D.) has done so. Investigating the metrical structure of poetry has been conducted in various languages, whereas scrutinising the metrical structure of English and Arabic poetry has received little attention. This study aims at capturing the
... Show MoreIn the field of implantology, peri-implantitis is still a common complication of implant failure. Similar to periodontal disease, this kind of pathological condition is characterized by inflammation of the tissues surrounding dental implants or fillings. The sources of infection have been shown to be chronic periodontitis and poor maintenance of the communion. A thorough examination of the intricate components of peri-implantitis was sought in this review in order to identify common characteristics of the disease with regard to bacteria, biofilm formation, host immunological responses, diagnostic tools, and therapeutic treatments. The aim of this study was to provide a detailed overview of the different bacterial species associated
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