The dust from pulverized coal weakens the acquired signal and increases the analysis difficulty for the quantitative analysis of the carbon content of pulverized coal when using laser-induced breakdown spectroscopy (LIBS). Moreover, there is a serious matrix effect and a self-absorption phenomenon. To improve the analysis accuracy, the DSC-PLS (double spectral correction-partial-least-squares) method was proposed to predict the carbon content of pulverized coal. Initially, the LIBS signal was corrected twice using P-operation-assisted adaptive iterative-weighted penalized-least-squares (P-airPLS), plasma temperature compensation, and spectral normalization algorithms. The goodness of fit of the carbon element was improved from nonlinearity to above 0.948. The modified signal was then used to establish DCS-PLS models for predicting unknown samples. In comparison to the conventional PLS model, the DSC-PLS method proposed in this paper significantly improves the ability to predict carbon content. The prediction error of the developed method was dropped from an average of 4.66% to about 0.41%, with the goodness of fit R² of around 0.991.

High switching-speed Silicon Carbide Metal-Oxide-Semiconductor Field-Effect Transistor (SiC MOSFET) has serious crosstalk issues. During the turn-ON transition and turn-OFF transition of the active switch in a phase-leg configuration, the voltage drops across the common-source inductor and the displacement current of the gate-drain capacitor of the OFF-state switch induce a spurious pulse on its gate-source voltage. This paper proposes a new gate driver using two Bipolar Junction Transistors (BJTs) and one diode to connect the gate terminal of SiC MOSFET and the negative driver voltage, which provides a low impedance path to bypass the displacement current of the gate-drain capacitor when crosstalk issues occur. The simulation results prove the proposed driver is valid on suppressing the crosstalk issue. The comparisons between the prior drivers and the proposed driver show the superiority of the proposed driver. Finally, the proposed gate driver is successfully implemented and experimentally verified on a 1.1 kW synchronous buck prototype.

Due to parasitic parameters existing in Silicon Carbide (SiC) devices application, SiC devices have poor turn-off performances. SiC diode and SiC MOSFET have severe turn-off overvoltage and oscillation. The DC-side snubber is one simple suppressing method. The simplest circuit is the high-frequency decoupling capacitor in parallel with the bridge leg. However, choosing the component value is empirical. Based on the turn-off terminal impedances of the SiC diode and the SiC MOSFET, the suppressing mechanism of this DC-side snubber is analyzed. The guideline selection for the component value is provided. Furthermore, the DC-side snubber with a damping resistor is analyzed based on the terminal impedances. The design principles are provided. Finally, the validity and effectiveness of the DC-side snubbers were proven based on the double-pulse test platform.

A novel hollow electrode RF glow discharge ion source detects CH ₃ ⁺ , C ₂ H ₃ ⁺ , C ₃ H ₈ ⁺ , C ₄ H ₇ S ⁺ , and [C ₄ H ₈ S + H] ⁺ to achieve the detection of methane, ethane, propane and tetrahydrothiophene in natural gas.

A novel hollow electrode glow discharge-quadrupole mass spectrometer was designed. The experimental platform of tube furnace + mass spectrometer was set up. Protein content in food was determined by measuring the intensity of NO ⁺ ions.