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This study deals with the preparation and characterization of polyethyl methacrylate/fatty acid blends as a novel form-stable phase change material for latent heat thermal energy storage applications. In the blends, fatty acids act as a phase change material when polyethyl methacrylate is operated as a supporting material. The fatty acids could be retained by 50 wt% into polyethyl methacrylate without melted phase change material seepage from the blends. Therefore, these blends are called form stable composite phase change materials and they have utility advantage without encapsulation in passive latent heat thermal energy storage applications. The prepared fatty acid/polyethyl methacrylate blends (50/50 w/w%) as form-stable phase change material was characterized using optic microscopy and Fourier transform infrared spectroscopy methods and the results showed that the polyethyl methacrylate was physically and chemically compatible with the fatty acids. Thermal properties and thermal stabilities of the form-stable phase change materials were measured using differential scanning calorimetry. Differential scanning calorimetry results indicated that the melting temperatures and latent heats of the prepared phase change materials are in the range of 30.67–61.09°C and 86.93–107.75 J/g, respectively. The thermal cycling test, including 5,000 cycling processes, was conducted to determine the thermal reliability of the synthesized form-stable phase change materials, and it is found that phase change materials were thermally and chemically stable after thermal cycling. On the basis of all the results, it was concluded that form stable polyethyl methacrylate/fatty acids composite phase change materials had important potential for practical latent heat thermal energy storage applications, such as under floor space heating of buildings and passive solar space heating of buildings by using wallboard, plasterboard, or floors impregnated with a form stable phase change material. [ABSTRACT FROM PUBLISHER]

This article aims to prepare novel shape-stabilized phase change materials (PCMs) by encapsulating fatty acids (stearic acid [SA], palmitic acid [PA], and myristic acid [MA]) as a PCM in an acrylic resin (Eudragit E) as supporting material and to determine latent heat thermal energy storage (LHTES) properties. The maximum percentage of all fatty acids in the shape-stabilized PCMs was found to be 70 wt% in which no fatty acid seepage was observed as the blends were heated over the melting points of the fatty acids. The optic microscope (OM) investigation demonstrated that fatty acid domains were coated by Eudragit E. Fourier transform infrared (FT-IR) results revealed that the interactions between Eudragit E and fatty acids were only adequate for adhesion of Eudragit E on fatty acid domains. Single phase was observed for the blends by OM, and interactions between the components were investigated by FT-IR spectroscopy. The melting and freezing temperatures and latent heats of the shape-stabilized PCMs were measured by the differential scanning calorimetry (DSC) method. Based on the results, it was concluded that Eudragit E/MA, Eudragit E/PA, and Eudragit E/SA blends (30/70 wt%) have good utility potential for LHTES purposes in terms of their satisfying thermal properties and advantages of easy preparation in desired dimensions, direct usefulness function in LHTES systems, and cost effectiveness. [ABSTRACT FROM AUTHOR]

Presents a comparative and phylogenetic analysis of the highly duplicated 16p12.2 region of the human genome, which is composed of at least four different segmental duplications spanning in excess of 160 kilobase. Discussion on fluorescence in situ hybridization; Comparison of the dispersal of the genomic segment with a second adjacent duplication called LCR16u; Discussion on the phylogeny of human genome duplication.