{'fraction_non_alphanumeric': 0.04039497307001795, 'fraction_numerical': 0.04308797127468582, 'mean_word_length': 4.962566844919786, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Synthesis of spherical α-alumina and its effect on the performances of phase change materials based on sodium acetate trihydrate

Spherical α-alumina was obtained by the homogeneous precipitation method using aluminum sulfate/nitrate as the aluminum source and formamide as precipitant. The effects of various synthetic parameters, such as the molar ratios of aluminum sulfate/nitrate, reaction time and temperature, and amount of formamide on the morphology and size of α-alumina were investigated and their effect on the performance of phase change materials based on sodium acetate trihydrate (SAT) have also been studied. Spherical α-alumina with average sizes of 153, 165, 183, 204, and 233 nm were prepared using 10 ml formamide as precipitant at Al2(SO4)3·18H2O/Al(NO3)3·9H2O molar ratios of 1:9, 2:8, 3:7, 4:6 and 5:5, respectively. Furthermore, the effect of content and α-Al2O3 particle size on the supercooling degree of SAT has also been explored. The results show that when 0.4 wt% spherical α-Al2O3 with an average size of 183 nm was introduced to SAT, the supercooling degree was minimal at ∼0.4 °C.