In this review, the recent advances of the application of 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN) as a photoredox catalyst in the past three years (2016–2018) for various organic reactions are summarized.

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All-solid-state linear transformer drivers (LTDs) are widely used in high-voltage repetitive nanosecond-pulsed generators, and only a few LTD generators can output bipolar rectangular waves currently. Furthermore, owing to the large reverse overshoot when the output pulse width is long, fewer LTD generators can achieve a rectangular wave output with a microsecond pulse width. In this study, a bipolar LTD circuit topology based on a push–pull circuit is proposed for irreversible electroporation. In this topology, a single-stage LTD module has four push–pull branches in its primary winding to achieve a bipolar output and a short-circuited winding with two resistor–capacitor–diode snubbers to suppress forward/reverse overshoot. A single-stage LTD module and a 12-stage LTD have been tested, and the results show that they can output bipolar rectangular pulses with variable parameters. When the output pulse width is 100 ns to 1 µs, the maximum output voltage amplitude is 5.74 kV, the rise time is 29.1 ns, and the reverse overshoot at 1 µs is 2.9%. When the output pulse width is 1–8 µs, the maximum output voltage amplitude is 2.93 kV, the rise time is 24.3 ns, and the reverse overshoot at 8 µs is 11.3%.

Pseudospark discharge is a special low pressure discharge and has been widely used in the gas switch and electron beam sources. From experiments, when the work pressure is relatively low, the electron beam current or loop current generated by a pseudospark discharge usually has two or more peaks, which has not been fully explained. In this paper, a single-gap pseudospark discharge model is established using 2D kinetic plasma simulation code VSim to study this phenomenon. According to the simulation results, when the anode voltage is 20 kV and the helium pressure is 100 Pa, the current has two peaks, which is similar to the experimental results, accompanied by the stepwise penetration of the virtual anode. This is mainly related to the formation and disappearance of the potential barrier in the cathode hole region. The formation of the potential barrier is caused by the consumption of ions at the cathode hole, and the disappearance is caused by the increase in electrons in the cathode cavity. By classifying the electrons, it is found that the increased electrons are generated by secondary emission caused by ion bombardment on the wall of the cathode. The simulation results also show that the stepwise penetration of the virtual anode can be suppressed or eliminated by increasing the working gas pressure, the secondary electron yield of the cathode material, or the trigger intensity.

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Polyfluoroaryl compounds belong to privileged moieties and engender distinct properties in many pharmaceuticals, agrochemicals, and materials. Over the past decade, considerable seminal reports and reviews merely pay closed attention to...

Xanthine is a significant biomolecule and its concentration level in urine and blood plasma is an indicator of specified pathological states. Here, a new sensing platform was designed, which showed excellent analytical performance for xanthine. Importantly, it is the first time to investigate the kinetics of xanthine metabolic reaction by electrochemical method. The results demonstrated that the conversion of xanthine to uric acid completely conformed to the Michaelis‐Menten kinetics. Furthermore, we also studied the inhibitory effect of febuxostat on xanthine oxidase activity detailed. As expected, the work may offer potential value for researchers in the treatment of hyperuricemia and gout.