Innovative bi–electrolyte solid-state cells incorporating single crystal CaF2 and composition-graded solid electrolyte (LaF3)y·(CaF2)1-y (y = 0 to 0.32) were used for measurement of the standard Gibbs energy of formation of hexagonal La0.885Al11.782O19 and cubic LaAlO3 from component binary oxides La2O3 and α-Al2O3 in the temperature range from 875 to 1175 K. The cells were designed based on experimentally verified relevant phase relations in the systems La2O3–Al2O3–LaF3 and CaF2–LaF3. The results can be summarized as: 5.891 α-Al2O3 + 0.4425 La2O3 (A-rare earth) → La0.885Al11.782O19 (hex), ΔGof(ox)( ± 2005)/J mol− 1 = −80982 + 7.313(T/K); 1/2 La2O3 (A-rare earth) + 1/2 α-Al2O3 → LaAlO3 (cubic), ΔGof(ox)( ± 2100)/J mol− 1 = −59810 + 4.51(T/K). Electron probe microanalysis was used to ascertain the non-stoichiometric range of the hexaaluminate phase. The results are critically analyzed in the light of earlier electrochemical measurements. Several imperfections in the electrochemical cells used by former investigators are identified. Data obtained in the study for LaAlO3 are consistent with calorimetric enthalpy of formation and entropy derived from heat capacity data. Estimated are the standard entropy and the standard enthalpy of formation from elements of hexagonal La0.885Al11.782O19 and rhombohedral LaAlO3 at 298.15 K.

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The word 'stress' nowadays has become a typical word and almost every individual at any stage, at any age of their life, experiences it. Social-emotional learning competencies are regarded as a good marker of how well adolescents adjust to their surrounding environments and these competencies aid adolescents in coping with social stress during adolescence. The objective of the study was to find out the association between social stress and social-emotional learning among adolescents. The data was collected from 500 adolescents in the age range of 13-14 years and Scale of Social Stress by Bisht (2005) was used to assess the level of social stress among adolescents. The study revealed that significantly more number of adolescents from nuclear families were at the average level of social frustration and social pressure dimensions of social stress. Adolescents from joint families significantly experienced more social pressure. Further, social-emotional learning was non-significantly positively correlated with social stress in joint families and nonsignificantly negatively correlated with social stress in nuclear families.