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To solve the problem of monitoring the temperature of high-voltage equipment in high-energy physics experiments, a new temperature testing method using fiber optic is presented in this paper, and the photoelectrical probe, the principle of optical fiber and the linear solution of the temperature-sensitive component are introduced. The experiment shows that this method has the advantages of measuring temperature in high-energy physics experiments where there is high voltage, strong magnetic fields, radioactivity and narrow spaces.

Based on the switched capacitor system theory, a new charge pump is designed as the driver of the H-bridge power circuits. The proposed circuit is added with the output feedback control module to realize the steady output, lower the ripple and power noise, and improve the transforming efficiency. Simulation based on 0.35 $\mu \mathrm{\text{m}}$ BCD350GE process demonstrates that the circuit has a ripple voltage as low as 200 mV and reaches a high efficiency up to 70% with a load as much as 20 mA when the supply voltage changes from 8 V to 36 V.

We here report a superconcentrated potassium acetate (KAC) solution (75wt.%, K : H₂O $=$ 1 : 1.8, called as “water-in-salt”) as an aqueous electrolyte to improve the working voltage and increasing capacitance in enhancing the energy density of the active carbon-based aqueous supercapacitor. The stability potential window of the superconcentrated electrolyte realizes an AC//AC symmetric supercapacitor with operating voltage of 2.0 V and excellent cyclic performance. Meanwhile, the energy density of such supercapacitor achieves about twice as high as that of the supercapacitor using normal concentration of electrolyte.

Electrolyte additive tris(trimethylsilyl) phosphite (TMSPi) was used to promote the electrochemical performances of LiNi${}_{0.5}$Co${}_{0.2}$Mn${}_{0.3}$O₂ (NCM523) at elevated voltage (4.5 V) and temperature (55${}^{\circ }$C). The NCM523 in 2.0 wt.% TMSPi-added electrolyte exhibited a much higher capacity (166.8 mAh/g) than that in the baseline electrolyte (118.3 mAh/g) after 100 cycles under 4.5 V at 30${}^{\circ }$C. Simultaneously, the NCM523 with 2.0 wt.% TMSPi showed superior rate capability compared to that without TMSPi. Besides, after 100 cycles at 55${}^{\circ }$C under 4.5 V, the discharge capacity retention reached 87.4% for the cell with 2.0 wt.% TMSPi, however, only 24.4% of initial discharge capacity was left for the cell with the baseline electrolyte. A series of analyses (TEM, XPS and EIS) confirmed that TMSPi-derived solid electrolyte interphase (SEI) stabilized the electrode/electrolyte interface and hindered the increase of interface impedance, resulting in obviously enhanced electrochemical performances of NCM523 cathode materials under elevated voltage and/or temperature.

In introductory Physics courses, one might come across a question of why electricity is transmitted from the power station at high voltage? Analysis of a typical quantitative question is illustrated in this paper, showing its deficiencies. An alternative method that mimics more closely to realistic situations is proposed to better illustrate the increase in efficiency of transmitting electrical power at high voltages.