A high-intensity low-frequency acoustic generator based on the Helmholtz resonator and airflow modulator.

The high-intensity low-frequency acoustic sources have essential applications in acoustic biological effects research, airport bird repelling, and boiler ash removal. However, generating high-intensity low-frequency acoustic waves in open space is difficult. In this paper, a low-frequency acoustic generator with a resonant cavity used to enhance the acoustic intensity in open space was developed, which is an aerodynamic acoustic generator to radiates a high-intensity acoustic wave of 52Hz.

Cubic AgBiS Powder Prepared Using a Facile Reflux Method for Photocatalytic Degradation of Dyes.

The ternary chalcogenide AgBiS has attracted widespread attention in the field of photovoltaic and photoelectric devices due to its excellent properties. In this study, AgBiS powders with an average diameter of 200 nm were prepared via a simple and convenient reflux method from silver acetate, bismuth nitrate pentahydrate, and n-dodecyl mercaptan. The adjustment of the ratios of Ag:Bi:S raw materials and of the reaction temperatures were carried out to investigate the significance of the synthesis conditions toward the composition of the as-synthesized AgBiS.

Solvent engineering to regulate the phase of copper zinc tin sulfide nanocrystals.

Copper zinc tin sulfide (CuZnSnS, CZTS) is attracting interest in photovoltaic applications due to its proper band gap, low cost and low toxicity. It has been found that two phases can be fabricated, kesterite and wurtzite CZTS structures. Though kesterite CZTS is proven to be thermodynamically stable, the free energy difference between kesterite and wurtzite CZTS is rather small.