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The purpose of this paper is to develop a coated glass fiber fabric which can be used as the outer shell of firefighters' protective clothing and replace aramid fabric.

The silicone resin with excellent heat resistance was selected as the base solution. Silica nanoparticles, mica powder and ferric oxide were added into the coating solution, which was coated on the glass fiber fabrics. The vertical burning, thermal protective performance (TPP) value, second-degree burn time and water repellency of the coated fabrics were characterized.

Results showed that the dosages of the thickening filler were in the range 4%–6%; the coating solution has good viscosity. The optimal composition of fillers added in the silicone resin is silica nanoparticles 6%, ferric oxide 5% and mica powder 6%. The TPP value of the optimum coated fabric is 413 kW·s/m². The second-degree burn time is 4.98 s, which is obviously higher than that of the original glass fiber fabric (3.49 s) and that of the aramid fabric (3.82 s). The coated fabric has better thermal stability than aramid fabric.

The production cost of this coated glass fiber fabric was much lower than that of the aramid fabric.

This paper aims to improve the general circuit of driving and protection based on insulated gate bipolar transistor (IGBT) in dielectric barrier discharge power supply by designing a novel half-bridge inverter circuit with discrete components.

With one SG3524 chip, the structure based on discrete components is used to design the IGBT drive circuit. The driving waveform is isolated and sent out by photo-coupler 6N137. The protection circuit is realized by Hall sensor directly detecting the main circuit current, supplemented by a few components, including diodes, resistors, capacitors and triodes. It improves the reliability of the protection circuit.

In the driving circuit, the phase difference of signals from two channels are 180°. Moreover, when the duty cycle is set at 40%, it can ensure sufficient pulse width modulation response time. In the protection circuit, when over-current occurs, an intermittent output signal is automatically sent out. Furthermore, the over-current response time can be controlled independently. The peak voltage can be adjusted continuously from 0 to 30 kV with its frequency from 8 to 25 kHz and the power output up to 150 W.

The novel circuit of driving and protection makes not only its structure simpler and easier to be realized but also key parameters, such as frequency, the duty cycle and the driving voltage, continuously adjustable. Moreover, the power supply is suitable for other discharges such as corona discharge and jet discharge.