Highly Selective Coextraction of H+/SO42- Using a Strapped Calix[4]pyrrole.

We report on the synthesis of a cage-type calix[4]pyrrole (1) bearing an additional basic pyridinebisthiazolamine group on the strap. The receptor in its protonated form shows strong affinity and selectivity for sulfate over a wide range of inorganic anions. With receptor 1 as a liquid-liquid extractant, H+/SO42- in the form of H2SO4 is almost quantitatively extracted from an aqueous solution containing HNO3 at a high concentration to CH2Cl2 in a recyclable manner.

Ultrafine Pt nanoparticles anchored on core-shell structured zeolite-carbon for efficient catalysis of hydrogen generation.

Ammonia borane (AB) is a potential hydrogen storage material with high-efficiency hydrolytic dehydrogenation under a suitable catalyst. Noble metal catalysts have drawn a lot of attention. In this study, a carbon-coated zeolite was obtained by calcination at high temperatures using glucose as a carbon source. Pt nanoparticles were fixed on a core-shell composite support by a simple chemical reduction method. A series of catalysts were prepared with different synthesis parameters. The results show that PSC-2 has excellent catalytic performance for hydrolytic dehydrogenation of AB in alkaline solution at room temperature, and the turnover frequency (TOF) is 593 min-1. The excellent catalytic performance is attributed to the carbon layer on the zeolite surface which inhibits the aggregation or deformation of metals in the catalytic reaction. The metal-support interaction activates the water and accelerates the rate-limiting step of hydrolysis. The activation energy (E a = 44 kJ mol-1) was calculated based on the reaction temperature. In addition, the kinetics of AB hydrolysis was studied, and the effects of catalyst concentration, AB concentration and NaOH concentration on AB hydrolysis rate were further investigated. The high-efficiency catalyst prepared in this work provides a new strategy for the development of chemical hydrogen production in the field of catalysis.

Relationship between grit and self-esteem in middle school students: the mediating role of self-identity / 中国学校卫生

Objective@#To explore the relationship among grit, self-identity and self-esteem and the mediating role of self-identity between grit and self-esteemin middle school students, so as to provide evidence for the study of grit of middle school students.@*Methods@#In March 2019,1 476 middle school students were selected from two ordinary middle schools in a county of Fujian Province. 12-Ttem Grit-scale, Selt-identity Scale and Selt-esteem Scale were used to conduct the questionnaire survey.@*Results@#Relevant analysis showed that perseverance of efforts, consistency of interests were positively correlated with self-identity (r=0.40, 0.31,P<0.01) and self-esteem (r=0.46, 0.18, P<0.01). Self-identity and self-esteem were positively correlated (r=0.67,P<0.01).The results of the mediation test showed that self-identity partially mediates the relationship between perseverance of efforts and self-esteem,mediation effect accounted for 50.38% of the total effect.Self-identity fullymediatesthe relationshipbetween consistency of interests and self-esteem.@*Conclusion@#The self-identity of middle school students partially mediates the relationship between perseverance of efforts and self-esteem, and completely mediates the relationship between consistency of interests and self-esteem.