Phase change material (PCM) is considered as one of the most effective thermal energy storage (TES) systems to balance energy supply and demand. A key challenge in designing efficient PCM-based TES systems lies in the enhancement of heat transmission during phase transition. This study numerically examines the privilege of employing twisted-fin arrays inside a shell-and-tube latent heat storage unit to improve the solidification performance. The presence of twisted fins contributes to the dominating role of heat conduction by their curved shapes, which restricts the role of natural convection but largely aids the overall heat-transfer process during solidification. The heat-discharge rate of twisted-fin configuration is increased by ∼14 and ∼55% compared to straight fin and no fin configurations—leading to a reduction in the solidification duration by ∼13 and ∼35%, respectively. The solidification front at various times has also been assessed through a detailed parametric study over the fin height, fin pitch number, and fin thickness. Over the range of values assumed, the fin height is the most dominant parameter – increasing the heat-retrieval rate from 10.0 to 11.4 W and decreasing the discharge time from above 3600 to 2880 s by varying the fin height from 2.5 to 7.5 mm.
Wireless communications are characterized by their fastest growth in history, as they used ever-evolving and renewed technologies, which have allowed them to spread widely. Every day, communication technology introduces a new invention with features that differ from its predecessor. Bell Laboratories first suggested mobile wireless communication services to the general population in the late 1940s. Still, it wasn't easy at that time to use on a large scale due to its high costs. This paper aims to describe the state of cellular mobile networks; by comparing the sources of electromagnetic pollution caused by these networks, measure the level of power density in some residential areas, and compare them with international standards adopted in
... Show MoreBack ground: Spectral analyses of solutions have long been applied to various body fluids for the purpose of clinical study as well as research .Human saliva can be easily obtained by non invasive .In this study typical spectra (for UV and IR) of saliva of oral cancer Squamous cell carcinoma patients were determined under average conditions and evaluated in relation to the spectra of normal specimens. Materials and Methods: Seventeen patients of oral cancer Squamous cell carcinoma and seventeen age matched healthy subject were included in this study .Chewing - Stimulated Saliva was collected in plastic test tube and stored at -20° C. Bach of saliva samples were used for UV and IR measurements. Results: Many differences between the IR spect
... Show MoreLet be a non-trivial simple graph. A dominating set in a graph is a set of vertices such that every vertex not in the set is adjacent to at least one vertex in the set. A subset is a minimum neighborhood dominating set if is a dominating set and if for every holds. The minimum cardinality of the minimum neighborhood dominating set of a graph is called as minimum neighborhood dominating number and it is denoted by . A minimum neighborhood dominating set is a dominating set where the intersection of the neighborhoods of all vertices in the set is as small as possible, (i.e., ). The minimum neighborhood dominating number, denoted by , is the minimum cardinality of a minimum neighborhood dominating set. In other words, it is the
... Show MoreBiological Activity of Complexes of Some Amino Acid
Objective: The study aimed to determine quality of life domains for adult patients with limbs loss and to identify
the association between quality of life domains and demographic characteristics and medical information.
Methodology: A descriptive study was carried out at Baghdad artificial limb center, Al-Salam medical
rehabilitation center, Al-Ghadeer medical rehabilitation center and the rheumatoid and medical rehabilitation
center for the period from September 2007 to April 2008. A purposive ''non- probability'' sample of (200)
patients with limbs loss. Questionnaire form was constructed for the purpose of the study. Data were collected
through the application of the questionnaire and interview technique. Data were a
The Detour distance is one of the most common distance types used in chemistry and computer networks today. Therefore, in this paper, the detour polynomials and detour indices of vertices identified of n-graphs which are connected to themselves and separated from each other with respect to the vertices for n≥3 will be obtained. Also, polynomials detour and detour indices will be found for another graphs which have important applications in Chemistry.
This review discusses the gingival biotypes, their characteristics, analysis based on the measurement of the dentopapillary complex. Also discuss their response to inflammation, surgery, and ridge healing after tooth extraction, their influence in the behavior of the peri-implant tissue
Abstract The study aimed at reviewing translation theories proposed to address problems in translation studies. To the end, translation theories and their applications were reviewed in different studies with a focus on issues such as critical discourse analysis, cultural specific items and collocation translation.
Objective(s): To determine the effectiveness of lactation counseling on maintenance of breastfeeding after
cesarean section for study group.
Methodology: A quasi-experimental study was conducted on non probability sample (purposive) of (60) women
who had cesarean section and sample divided in to two groups (30) of them as a study group from Fatima AlZahra'a
Maternity and Pediatric Teaching Hospital & implement lactation counseling on it and another group (30)
as control group from Baghdad Teaching Hospital in Baghdad City. Study implemented for the period of April 24th
2011 to August 2nd 2011. A questionnaire was used as a tool of data collection to fulfill with objective of the study
and consisted of three parts
The aim of this paper is to determine the feasibility of using fluorometric methods as an indicator for quality and contamination of milk with E.coli bacteria, and selection the suitable wavelength to be used with laser induced auto fluorescence. Three groups of milk samples were used in this study: Fresh pasteurized milk samples, milk samples containing different concentration of E.coli bacteria which were added artificially, and milk samples that were kept in refrigerator for 3-5 days. Thirteen excitation wavelengths were used to get the emission spectra for all milk samples using spectroflourometer .The results showed that the emission spectra at 275nm excitation wavelength gave a good differentiation between these three groups.
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