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This study investigated the causes of microstructural changes and the resultant electrical properties according to the sintering temperature of 0.96(K0.46−xNa0.54−x)Nb0.95Sb0.05O3-0.04Bi0.5(Na0.82K0.18)0.5ZrO3 lead-free ceramics by analyzing the correlation between vacancy concentrations and 2D nucleation. When sintered for 4 h, no grain growth occurred for the x = 0.000 composition over a wide temperature range, demonstrating that the existence of initial vacancies is essential for grain growth. As x increased, that is, as the vacancy concentration increased, the critical driving force (ΔGC) for 2D nucleation decreased, and abnormal grain growth was promoted. The number and size of these abnormal grains increased as the sintering temperature increased, but at sintering temperatures above 1100 °C, they decreased again owing to a large drop in ΔGC. The x = 0.005 specimen sintered at 1085 °C exhibited excellent piezoelectric properties of d33 = 498 pC/N and kp = 0.45 due to the large number of large abnormal grains with an 83% tetragonal phase fraction. The x = 0.000 specimen sintered at 1130 °C with suppressed grain growth exhibited good energy storage properties because of its very high relative density and small grain size of 300 to 400 nm. [ABSTRACT FROM AUTHOR]

This study investigated the perception bias on affective emoticons in individuals with emotion dysregulation and a maladaptive regulation strategy. A total of 289 students from the university completed 1) the Cognitive Emotional Regulation Questionnaire, including both adaptive and maladaptive cognitive emotional strategies, 2) the Difficulties in Emotion Regulation Scale, 3) an emoticon rating in terms of perception intensity, based on 6 basic emotions. Twenty-six emoticons from KakaoTalk, a popular messenger application in South Korea, were used after arousal whereupon valence ratings were obtained. The results revealed that individuals with emotion dysregulation significantly displayed stronger perception to ambiguous affect emoticons in anger and fear emotions, as compared to the control. These findings suggest that individuals with emotion dysregulation may be more influenced by negative affect stimuli which then leads to daily negative affect bias. [ABSTRACT FROM AUTHOR]