In this paper, the characteristic behavior of the disc consisting of thermoplastic composite CF/PA6 material was considered. Analysis was made by taking into account the usage areas of the materials and referring to certain temperatures between 30 ℃ and 150 ℃. Composite materials are lightweight; they show high strength. For these reasons, they are preferred in technology, especially in the aircraft and aerospace industry. With this study, the radial and tangential stresses determined within a certain temperature The temperatures were determined and compared with previous studies in the literature. According to the results obtained, it is believed that the thermoplastic composite CF/PA6 disc design can be used in engineering.

A salinity gradient solar pond (SGSP) is a large and deep artificial basin of layered brine, that collects and stores simultaneous solar energy for use in various applications. Experimental and theoretical studies have been launched to understand the thermal behavior of SGSPs, under different operating conditions. This article then traces the history of SGSPs, from their natural discovery to their current artificial applications and the progress of studies and research, according to their chronological sequence, in terms of determining their physical and dynamic aspects, their operation, management, and maintenance. It has extensively covered the theoretical and experimental studies, as well as the direct and laboratory applications of this technology, especially the most famous and influential in this field, classified according to the aspect covered by the study, with a comparison between the different results obtained. In addition, it highlighted the latest methods to improve the performance of an SGSP and facilitate its operation, such as the use of a magnetic field and the adoption of remote data acquisition, with the aim of expanding research and enhancing the benefit of this technology.

In this work, the structural transformations of a suboxide vacuum-deposited film of SiO_1.3 composition annealed in an inert atmosphere in a wide temperature range of 100 °C–1100 °C were characterized by the reflection-transmission spectroscopy technique. The experimental spectroscopic data were used to obtain the spectra of the absorption coefficient α(hν) in the absorption edge region of the film. Based on their processing, the dependences of Urbach energy EU and optical (Tauc) bandgap Eo on the annealing temperature were obtained. An assessment of the electronic band gap (mobility gap) Eg was also carried out. Analysis of these dependences allowed us to trace dynamics of thermally stimulated disproportionation of the suboxide film and the features of the formation of nanocomposites consisting of amorphous and/or crystalline silicon nanoparticles in an oxide matrix.

The search for the development of nanostructured materials has led to the study of the properties of their precursors. For the production of nanofibers by the electrospinning process, it is necessary to determine the rheological parameters of the precursor solutions. Since these properties can be influenced by the processing variables and chemical composition of the polymer, this study aims to elucidate the effect of the addition of vinyl monomers in the formulation of nanofibers based on polyacrylonitrile and to determine the optimal parameters for the production of the precursor polymer solution. The effects of temperature and addition of vinyl monomers were evaluated by rheometry, from the analysis of the variation of the viscosity of the solutions, and by microscopy, the morphology of the nanofibers produced. It was observed that the increase in the temperature used to produce the solutions improves the fibers’ properties. Still, there is a relationship between the time of exposure of the polymeric solution to the temperature and the homogeneity of the fibers, which cannot exceed 45 min. The addition of vinyl monomers, to produce PAN-PVA co-polymeric fibers, increases the conductivity and reduces the viscosity of the solutions, resulting in more refined and homogeneous fibers.

The electron/hole transport layer can promote charge transfer and improve device performance, which is used in perovskite solar cells. The nanoarray structure transport layers can not only further promote carrier transport but also reduce recombination. It also has a great potential in enhancing perovskite light absorption, improving device stability and inhibiting the crack nucleation of different structure layers in perovskite solar cells. This paper reviewed the research progress of perovskite solar cells with different nanoarray structure transport layers. The challenges and development directions of perovskite solar cells based on nanoarray structure transport layers are also summarized and prospected.

The direct expansion heat pump with solar energy is an energy conversion system used for water heating applications, air heating for air conditioning buildings, water desalination, solar drying, among others. This paper reviews the main designs and analysis of experiments in order to identify the fundamental objectives of any experiment which may be: to determine the factors that have a significant influence, to obtain a mathematical model and/or to optimize performance. To achieve this task, the basic and advanced configuration of this system is described in detail in order to characterize its thermal performance by means of energy analysis and/or exergy-based analysis. This review identifies possible lines of research in the area of design and analysis of experiments to develop this water heating technology for industrial applications.