The physical, chemical and electrical properties of a coaxial Dielectric Barrier Discharge (DBD) fed by various mixtures of N 2 and CH 4 at atmospheric pressure and ambient temperature has been studied. FTIR spectral measurements of the products formed in the discharge have shown that the main chemical products are C 2 H 2, HCN and C 2 H 6 produced by dissociation of CH 4 , with small but significant traces of NH 3 .such a chemical transformation may provide some insight into the chemical processes prevalent in the atmosphere of Titan. During operation of the discharge a solid brown-yellowish deposit was formed on the central rod electrode and the dielectric pellets. Such a deposit is similar to that observed in other N 2 :CH 4 discharges and is believed to be an analogue of the aerosol and dust observed in Titan's atmosphere being composed of chemical species commonly known as 'tholins'.

The ionization mechanism of Atmospheric Pressure Chemical Ionization (APCI) for dimethyl phthalate isomers using an Ion Mobility Spectrometry (IMS) experiment combined with Density Functional Theory (DFT) calculations.

In this work, we present the application of a fast and sensitive microanalytical method, microchip capillary electrophoresis (MCE), for the determination of NO2− and NO3− ions in deionized water treated by atmospheric pressure plasma jet (APPJ). The MCE technique consisted of an online combination of isotachophoresis with zone electrophoresis, both performed on the microchip. The argon plasma has been characterized by optical emission spectroscopy (OES) and Fourier transform infrared spectroscopy (FTIR). OES confirmed the presence of argon excited species (Ar I) emission (4p → 4s) lines, N2 emission bands (second positive system C3Πu → B3Πg), and OH band (A2∑+ → X2Π Δv = 0), as well as the presence of NO and excited NO2. The presence of NO2 molecules was also confirmed by FTIR absorption spectroscopy. The performance of the developed MCE method was evaluated for linearity, limit of detection, limit of quantitation, precision, and accuracy, and the concentration of NO2− and NO3− in the water as a function of the water treatment time was monitored.

The present study compares the operation of two cold atmospheric plasma jet (CAPJ) configurations: needle‐to‐cylinder electrode configuration (CAPJ I) and single high‐voltage cylinder electrode around the quartz tube (CAPJ II). The CAPJs were operated in argon flowing through a quartz capillary with 0.5‐mm inner diameter into the ambient air, and the plasma was generated by sinusoidal kHz frequency AC power supplies. The main emphasis of the study was on the mechanism of the initiation of ionization waves for these two configurations. For both CAPJs, there appeared several ionization waves during one half‐period of the applied voltage waveform, and the number of ionization waves increased at higher voltage amplitudes. However, we discovered marked differences in the initiation of the ionization waves for two different CAPJ configuration. The applied voltage controlled the initiation of consecutive ionization waves, which propagated from the grounded electrode towards the tube orifice in CAPJ I. In the case of CAPJ II, certain time had to pass for the initiation of a new ionization wave, and subsequent ionization waves within the same half‐period started at the tube orifice. In addition to the differences in the initiation of the ionization waves, we observed that the CAPJ I was ignited and sustained at lower voltages, while CAPJ II produced a longer plasma jet. The observed advantages and deficiencies of investigated CAPJ configurations point out their potential in different applications.

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