Abstract Plasmas in contact with liquids are a rich source of OH radicals and have been extensively studied the last decade to leverage ability generate chemically reactive species gas phase plasmas decompose organics. Multiphase transfer is highly transport limited overcome limits, plasma activation aerosols, small liquid droplets, interspersed has proposed. In this work, we report combined experimental modeling study controlled plasma–droplet interaction experiment using diffuse RF glow...

Although atmospheric pressure dielectric barrier discharges (DBDs) have a long history, the effects of water vapor on discharge morphology and kinetics not been studied intensively. We report simultaneous investigation morphology, OH H2O2 production in Ar He DBDs operated at different concentrations powers. The combined study allows us to assess impact power concentration dependence production. is investigated by ICCD images current–voltage waveforms. These diagnostics are complemented...

Sulfur-containing small molecules, mainly including cysteine (Cys), homocysteine (Hcy), glutathione (GSH), and hydrogen sulfide (H2S), are crucial biomarkers, their levels in different body locations (living cells, tissues, blood, urine, saliva, etc.) inconsistent constantly changing. Therefore, it is highly meaningful challenging to synchronously accurately detect them complex multi-component samples without mutual interference. In this work, we propose a steric hindrance-regulated probe,...

Abstract H2S is a toxic pollutant that threatens human health and industrial integrity by causing respiratory irritation, metal corrosion, equipment damage. Accurate, real-time monitoring critical due to strict emission regulations, but challenges persist in detecting low concentrations addressing adsorption effects on material surfaces, complicating measurement accuracy. This study investigates the of under continuous-flow conditions, examining various gas parameters surface materials....

A highly sensitive, calibration-free method, wavelength modulation - direct absorption spectroscopy (WM-DAS), is proposed by extracting the characteristic frequencies of modulated laser intensity. This method combines advantages measuring absolute absorbance profile from DAS with enhanced noise rejection and high sensitivity WMS. The preliminary validation experiment H2O transitions shows that WM-DAS improves accuracy measurement a best-fit standard residual 4.9 × 10-5. new might inspire...

A novel method with high accuracy and easy implementation was proposed based on the sinewave-scanned direct absorption spectroscopy (DAS) in this paper. fitting routine time domain developed to simultaneously deduce baseline more importantly, absorbance through explicit expression offered by sinewave scan. This effectively solves difficulties of determination provides accurate wavelength calibration compared conventional DAS. The performance narrow scans frequency were experimentally...

The absorbance is of great importance in the tunable diode laser absorption spectroscopy (TDLAS) as it contains information both gas properties and spectroscopic parameters. A novel, calibration-free wavelength modulation-direct (WM-DAS) proposed experimentally verified this two-part paper. This method combines capability measurement from DAS advantages enhanced noise rejection high sensitivity WMS. In Part I, we focus on full theoretical basis procedures following three aspects:...

The micro-discharge properties and evolution in a 2D array of integrated coaxial microhollow dielectric barrier discharges are studied by using highly time-resolved electrical optical diagnostics. study is focused on the effect gas flow rate residence time discharge properties. investigated geometry allows operating at exceptionally small times, which can be equal to or even smaller than period, reasonable rates. has an impact heating, residual humidity, pre-ionization density densities...

The measurement of absolute densities ubiquitous OH radicals and gas temperatures in water containing plasmas has recently drawn a lot attention. In this paper, we extend the self-absorption model introduced Du et al 2016 Plasma Sources Sci. Technol. 25 04LT02 with description excited state by superposition two Boltzmann distributions to take non-thermal rotational distribution into account. This technique is applied diffuse He + H2O RF discharge it shown that addition determination ground...

Considering the importance of laser wavelength response and difficulty in its real-scenario measurement WMS, a high-accuracy universal method was developed to characterize relative (RWR) by analyzing current response. A coupling term that depends on both scan modulation characteristic introduced describe effect between modulation. The accuracy proposed verified with different working conditions waveforms. All fitting residuals RWR result from are smaller than 0.1% total range residual ramp...

Following the theoretical work in Part I, this experimental study, robustness, temporal resolution, and narrow scan performance of proposed wavelength modulation-direct absorption spectroscopy (WM-DAS) method are experimentally validated a high-temperature tube furnace. The electromagnetic other random-frequency noises can be effectively eliminated by extracting characteristic spectra light intensity. WM-DAS with modulation frequencies from 0.1 to 100 kHz indexes 3.3 11.1 also investigated...