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• One-dimensional vortex-arrays with singularity tuned from 1 to 4 have been achieved. • Four-singularity vortex-array with peak power of 5.56 kW has been achieved. • A method for developing pulsed one-dimensional vortex-array with tunable singularity. One-dimensional (1D) vortex-arrays with multiple-singularity aligning along a line are flexible for microparticle manipulation, high capacity storage, material processing. Moreover, a high peak power one-dimensional vortex-array with large singularity enables assemble processing. The development of a miniature laser to directly generate one-dimensional vortex-array with tunable singularity is of great value for practical applications. However, solid-state lasers for this purpose was limited by the low power, low efficiency and less singularity achieved. Here, we demonstrate a simple and robust method for directly generating one-dimensional vortex-array with singularity tunable upon to 4 in a tilted Nd:YAG/Cr4+:YAG composite crystal passively Q-switched (PQS) microchip laser, irradiated by a decentered annular beam (DAB). The singularity of one-dimensional vortex-array can be tuned from 1 to 4 by controlling the offset of collimating lens, Δ x. The average output power of one-dimensional vortex-array with 4 singularities is 0.76 W at P in = 5.66 W, the optical conversion efficiency is 13.4%. One-dimensional vortex-array with 4 singularities processes pulse width of 3.5 ns, peak power of 5.56 kW. The achieved results suggest the potential that DAB can be used a practical pump beam in PQS microchip laser for generating nanosecond, high peak power one-dimensional vortex-arrays with tunable singularity. [ABSTRACT FROM AUTHOR]

In this work, a mesoporous zinc oxide containing different concentrations of oxygen vacancies (V O) was controlled synthesized via low temperature annealing. XPS, Raman spectroscopy and electron paramagnetic resonance spectroscopy were employed to investigate the changes of V O concentrations following the increase of annealing temperature. According to the experiment, the highest concentration of V O was obtained at the annealing temperature of 350 °C. The relationship between photoelectrochemical biosensor performance and V O concentration was discussed in detail in terms of electrochemical measurements and V O characterization. Results showed that increasing the V O could result in high carrier intensity, active sites and catalytic rate constant. In addition, the performance toward glucose detection could be improved by increasing V O. [ABSTRACT FROM AUTHOR]