The preparation of NaLnF4 complexes, LnF3 (Ln = La, Ce, Y) rare earth binary fluorides, CaF2 and SrF2 alkali earth fluorides, as well as mixtures of these compounds from their nitrates dissolved in molten NaNO3 has been studied in order to select the ideal solvent for fluoride synthesis by spontaneous crystallization from flux. Sodium fluoride (NaF) was used as a fluorinating agent. The results of our experiments have confirmed that NaNO3 melt is one of the most promising media for precipitating said inorganic fluoride materials within a broad temperature range (300–500 °С). Also, in co
The rapid urbanization in Northwest China highlights the mismatch of increasing energy demand and limited local energy supply. Nevertheless, the remote areas in Northwest China are abundant with rich solar energy resources and land space resource. Therefore, establishing a distributed solar energy system (DSES) is a feasible solution to the energy supply problem in remote Northwest China. Due to the strong fluctuations in the availability of solar energy, operation strategies based on fixed parameters may not ensure optimal operation of DSESs. In this study, dynamic operation strategies tha
Fluoride-containing alkali-free setting accelerators are a common type of admixture used in tunnel shotcrete but few studies in the literature focus on the effect of their fluoride compounds on the setting and hardening properties of accelerated cement paste under low environment temperatures. Tunnel shotcrete in cold regions or winter construction periods would be obviously influenced by low environment temperatures, especially for its fast setting and quick support applications. The objective of this work is to evaluate the early age hydration behavior of different accelerated cement past
