Abstract: A pulse width modulation power supply method, and an electronic high-voltage energy extraction and sampling apparatus and method. The apparatus uses a high-voltage energy extraction module composed of a high voltage-side element and a low voltage-side element, so that the electronic high-voltage energy extraction and sampling apparatus can achieve the purpose of high-efficiency voltage energy extraction, and implement the characteristics of high power factor and high conversion efficiency. A waveform characteristic of a voltage of a high-voltage power supply is indirectly reflected by means of a current in the low voltage-side element of a low-voltage arm, so that the purpose of monitoring the voltage of the high-voltage power supply is achieved.

Abstract: A nanoparticle comprises water-insoluble polymer matrix and an indicator constituent(s), wherein the indicator constituent(s) is released from the nanoparticle only when the polymer matrix is degraded or broken, and then an indicative effect is triggered or enhanced. A nanoparticle-based method for screening a bioactive substance and a microfluidic-based screening system have also been disclosed.

Abstract: Techniques for charging a rechargeable battery having at least one rechargeable cell are described. A battery charger applies a constant current to charge the rechargeable cell and periodically measures a value of voltage of the rechargeable cell. The value of voltage is tracked over a time period required to charge the rechargeable cell to have the measured value of voltage be substantially equal to a crossover value of voltage for the rechargeable cell. A constant voltage is applied substantially equal to the crossover voltage for a second period of time, with the second period of time selected based on the tracked time period. The charging is terminated after the second period of charging time has elapsed.