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An all-dielectric transparent metamaterial absorber with encapsulated water is demonstrated in this paper. Because the proposed absorber is realized using only water and polydimethylsiloxane (PDMS) without any conductive patterns, optical transparency is achieved. In addition, the high dielectric loss of water renders it a good candidate for an electromagnetic absorber. The absorptivity is increased by encapsulating the water within the PDMS, and the absorptivity of the proposed absorber is numerically compared with that of the PDMS and water with the same size. When the proposed absorber is realized using two layers, 92.5% absorptivity is achieved at 10.8 GHz, and the absorptivity exceeds 90% in the range of 10.45 to 11.20 GHz, which corresponds to 6.9% bandwidth. Therefore, the proposed absorber has advantages of high transparency, low cost, wide absorption bandwidth, and eco-friendly fabrication.

In order to achieve greater enhancements in energy sustainability for housing, the function and efficiency of two different passive cooling systems were studied: encapsulated water in recycled bottles of Polyethylene terephthalate (PET) and polystyrene plates, in comparison with standard concrete slab systems, which are customarily used in housing. Experiments were placed over a tile surface, in which temperature changes were monitored for a period of 20 days from 08:00 to 20:00. The efficiency of passive thermal storage systems was endorsed through statistical analysis using the "SPSS" software. This resulted in a 17% energy saving, thus promoting energy sustainability in housing units, which reduces the use of electrical appliances required to stabilize conditions to achieve optimum thermal comfort for the human body inside a house, therefore, reducing electrical power consumption, CO2 emissions to the atmosphere and generating savings. Due to the complexity of a system with temperature changes, a fractal analysis was performed for each experimental system, using the "Benoit" software (V.1.3 with self-compatible tools of rescaled range (R/S) and a wavelets method), showing that the thermal fluctuations on the tiles with the thermal storage system adapt to the rescaled range analysis and the regular tiles adapt to the wavelets method. [ABSTRACT FROM AUTHOR]

Abstract: Starting from the structure of ice (in which each water molecule is surrounded by other four water molecules forming a tetrahedron with a value of 4.51Å for the edge O–O distance), and the knowledge that this value also corresponds to the O7–O12 distance of the skeleton of cholic acid, it is hypothesized that two steroid cholic acid moieties, with an appropriate steroid–steroid distance and a belly-to-belly orientation, could encapsulate a single water molecule between them. To check this hypothesis two succinyl derivatives of cholic acid (a monomer and the related head–head dimer in which the succinyl group is the linking bridge) were designed. The expected “ice-like” structure is found in the crystal of the dimer. There is a hydrogen bond synergy between those participating in the “ice-like” structure, and those in which the bridge is involved with the O7–H hydroxy group and the side chain of the steroid. [Copyright &y& Elsevier]