Interaction and Stability of Nanobubbles and Prenucleation Calcium Clusters during Ultrasonic Treatment of Hard Water.

To investigate the stability of nanobubbles in natural hard water, a series of eight samples ranging in hardness from 0 to 332 mg/L CaCO were sonicated for periods of 5-45 min with an ultrasonic horn. Conductivity, temperature, ζ-potential, composition, and pH of the water were analyzed, together with the crystal structure of any calcium carbonate precipitate. Quasi-stable populations of bulk nanobubbles in Millipore and soft water are characterized by a ζ-potential of -35 to -20 mV, decaying over 60 h or more.

Copper-Catalyzed Annulation of Electrophilic Benzannulated Heterocycles with 2-Aminopyridine and 2-Aminoquinoline: Direct Access toward Polyring-Fused Imidazo[1,2-]pyridines.

We have developed a direct method for the synthesis of polyring-fused imidazo[1,2-]pyridines via a copper-catalyzed annulation of electrophilic benzannulated heterocycles with 2-aminopyridine and 2-aminoquinoline. From 3-nitroindoles and 2-aminopyridine, we could synthesize tetracenes, viz., indole-fused imidazo[1,2-]pyridines, and by starting from 2-aminoquinoline, we could generate pentacenes, viz.

Evaporation of water and urea solution in a magnetic field; the role of nuclear isomers.

Hypothesis: Ortho and para water are the two nuclear isomers where the hydrogen protons align to give a total nuclear spin of 1 or 0. The equilibrium ratio of 3:1 is established slowly in freshly evaporated water vapour while the isomers behave distinct gasses, with their own partial pressures. Magnetic-field-induced ortho ⟷ para transformations are expected to alter the evaporation rate.

Does Gratitude Ensure Workplace Happiness Among University Teachers? Examining the Role of Social and Psychological Capital and Spiritual Climate.

The study examines the necessity and sufficiency of gratitude for supporting workplace happiness among Indian university teachers. It also explores the mediating effect of psychological capital and social capital in the relationship between gratitude and workplace happiness. The moderating effect of spiritual climate is investigated.

Bioplastic films with unusually good oxygen barrier properties based on potato fruit-juice.

In this study, the use of potato fruit juice (PFJ) to make plastic films is presented. PFJ is an interesting raw material as it is obtained as a by-product from the potato-starch industry. The films showed uniquely high oxygen barrier properties, and the PFJ material is therefore a potential replacement for the most commonly used, expensive and petroleum-based ethylene-vinyl alcohol copolymer (EVOH) as a barrier layer in future packaging.