Sodium acetate trihydrate phase change materials (SAT-PCMs) for thermal energy storage have been studied and applied widely because of their enhanced energy efficiency and environmental friendliness, while their application on energy exchanging requires stable chemical property and great heat storage-release merit. Nanoparticles-modified tetrahedrite (CNAS-NPs) composites show high thermoelectric properties among copper sulfides, and present excellent nucleating performance in SAT-PCMs. As characterized, the NPs were uniformly distributed into the CNAS grains, and a large number of nanopores were appeared in the grain boundaries after SPS treatment. As a heterogeneous nucleation site, NPs were used to reduce the thermal conductivity, but simultaneously maintained a relatively high electrical conductivity. As a result, by adding a small quantity of SiC, a relatively high ZT ∼ 1.0 at 723 K is obtained, which increases by ∼42% in the pure CNAS sample. Finally, the CNAS-NPs regarded as nucleating agents obviously decrease the supercooling degree and improve the heat storage-release cycle property. These SAT-PCMs also possess high latent heat, fine chemical stability and robust nanostructures, which illustrates promising potentials in practical applications.

In order to provide the solution for deficient diachronic data in the reliability of distribution network, a data restoration strategy is proposed on the basis of Cartesian product, time series analysis and multiple interpolation. The author conduct the empirical investigation for the reliability data of distribution network in a province in 2016 so as to verify the accuracy about the reliability analysis of distribution network through the proposed diachronic data restoration strategy and to provide the valuable research perspectives and methodologies for the study of reliability data of distribution network in future.

The encapsulation and heat conduction of molten salt are very important for its application in heat storage systems. The general practice is to solidify molten salt with ceramic substrate and enhance heat conduction with carbon materials, but the cycle stability is not ideal. For this reason, it is of practical significance to study heat storage materials with a carbon-free thermal conductive adsorption framework. In this paper, the in-situ reaction method was employed to synthetize the constant solid-state composites for high-temperature thermal energy storage. AlN is hydrolyzed and calcined to form h-Al₂O₃ with a mesoporous structure to prevent the leakage of molten eutectic salt at high temperature. Its excellent thermal conductivity simultaneously improves the thermal conductivity of the composites. It is found that 15CPCMs prepared with 15% water addition have the best thermal conductivity (4.928 W/m·K) and mechanical strength (30.2 MPa). The enthalpy and the thermal storage density of 15CPCMs are 201.4 J/g and 1113.6 J/g, respectively. Due to the excellent leak-proof ability and lack of carbon materials, the 15CPCMs can maintain almost no mass loss after 50 cycles. These results indicate that 15CPCMs have promising prospects in thermal storage applications.