Ambient molecular beam mass spectrometry (MBMS) has been used to study how different capillary widths (530 µm and 2.4 mm) excitation waveforms (continuous wave kHz pulsed dc) affect the ionic composition of atmospheric pressure plasma jets. It is shown from time-averaged ion intensities that reducing width jet results in a significant increase variety both positive negative ions detected within discharge. We discuss this terms changes flow velocity onset turbulence plume. Changing mode had...

The propagation dynamics of an atmospheric-pressure plasma jet resemble that a cathode-directed streamer and are determined, in part, by the high localized electric field at head. This contribution employs optical spectroscopy technique based on polarization-dependent Stark splitting shifting visible helium lines to non-invasively measure head field. It is demonstrated comprised high-field region with peak magnitude ∼24 kV cm−1, which followed low-field region, ∼9 identified as tail....

Abstract This study focuses on the generation and loss of reactive oxygen species (ROS) in low-temperature atmospheric-pressure RF (13.56 MHz) He + O 2 H plasmas, which are interest for many biomedical applications. These plasmas create cocktails ROS containing ozone, singlet oxygen, atomic hydroxyl radicals, hydrogen peroxide hydroperoxyl i.e. great significance as recognized by free-radical biology community. By means one-dimensional fluid simulations (61 species, 878 reactions), key their...

Abstract Low-temperature atmospheric pressure plasma jets are generally small in scale (~few mm)
and often require high-breakdown voltages and high value gases to operate. This study
investigates the advantageous properties of a novel multi-electrode jet-like source with
separately powered (180o phase-shifted) live electrodes, namely significantly reduced
breakdown voltage, increased operating voltage range higher gas admixture capabilities.
Gas...

Abstract The vibrationally resolved ground state Yacora model for H2 (Yacora H2(X1, v)) has
been used to calculate the vibrational distribution and thus from cross-sections of the
Yacora v) effective rate coefficients molecular processes relevant to
detachment. A reduced extended implementation was constructed
to form EIRENE-style databases use in SOLPS-ITER. implementation
utilises same as EIRENE, but with updated cross-sectional data, whilst...

The linker-free covalent immobilization of polymers on surfaces has the potential to impart new properties and functions for a wide range applications. However, most current methods production these involve multiple chemical steps do not have high degree control over functionalities at surface. A comprehensive study detailing facile two-step grafting antimicrobial peptide nisin onto polystyrene is reported. Functionalization achieved using an atmospheric pressure plasma jet, reaction...

Using advanced mass spectrometry the chemistry of ionic species present in an atmospheric pressure parallel plate dielectric barrier discharge (DBD) with a single on powered electrode have been identified.The was driven helium controllable concentrations water vapour using excitation frequency 10 kHz and applied voltage 1.2 kV.Both negative positive ions were identified their relative intensity determined variation concentration discharge, inter-electrode spacing, gas residence time nominal...

Abstract This paper presents a novel approach for the generation of heart Beats Per Minute (BPM) from noisy/distorted underwater Electrocardiogram (ECG) samples. We solve this problem using software based via Convolutional - Recurrent (CNN-RNN) regression model and demonstrate good performance: Mean Absolute Error (MAE): 0.400, Root Square (RMSE): 0.653 counted beats. The neural network is trained on land ECG samples that have been modified by replicating signal noise/artefacts seen under...

We report on intricate dynamics observed in atmospheric-pressure rf electronegative discharges where electrons and anions are separated due to their different mobilities. This results the formation of positively charged regions between an plasma core oscillating electron ensemble. It is found that for a given input power, electron, ion (both positive negative) neutral fluxes increase as gap size reduced, resulting more efficient delivery chemical species treated target.

Plasma-based desorption/ionization sources are an important ionization technique for ambient surface analysis mass spectrometry. In this paper, we compare and contrast three competing plasma based sources: a radio-frequency (rf) needle, dielectric barrier jet, low-temperature probe. The composition of the their effectiveness at analyzing range pharmaceuticals polymers were assessed. Results show that background spectrum each source was dominated by air species, with rf needle producing...

Pulse-modulated generation of atmospheric pressure plasma promises lower operating temperatures and enhanced energy efficiencies compared with those generated using continuous excitation. In this study, the effect pulse modulation on ionic content a radio-frequency helium needle was explored molecular beam mass spectrometry (MBMS). all cases reported repetition frequency held constant at 6 kHz while duty cycle distance between MBMS were varied from 30% to 90% 4 mm 10 mm, respectively....

A systematic characterisation and optimisation of parameters a plasma-mediated ion source to achieve the best spatial resolution for MSI.

To improve understanding of atmospheric-pressure plasma polymerization processes, the gas-phase ion chemistry acrylic acid produced in a microsecond pulsed atmospheric pressure jet has been studied using ambient mass spectrometry. Acrylic monomer was introduced into helium feed prior to entry active discharge region and pulse duty cycle varied from 10–90% for frequencies 5 10 kHz. The ionic spectra show rich variety species up 450 Da with prominent peaks at masses corresponding both positive...

Ambient molecular beam mass spectrometry has been employed to examine the effects of mode operation and excitation waveform on ionic content a helium-based atmospheric-pressure parallel plate dielectric barrier discharge. By applying 10 kHz microsecond voltage pulses with nanosecond rise times sinusoidal waveforms, distinctly different glow Townsend modes were produced, respectively. Results showed significant difference in dominant ion species between two modes. In mode, oxygen ions, atomic...

Double-layer

Abstract Type-II superlattice devices have the potential to be new generation of semiconductor-based devices, however fabrication these leads surface defects that can create leakage channels. Passivation methods are typically used in traditional semiconductors proved unsuccessful. In this paper we present initial findings a low-temperature atmospheric pressure plasma polymerisation process capable removing unwanted oxide layers and depositing thin layer polymer protect surface. We examine...

Summary form only given. This study focuses on the generation and loss of reactive oxygen species (ROS) in low-temperature atmospheric-pressure rf (13.56MHz) He+O <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> +H O plasmas, which are interest for many biomedical applications.

Summary form only given. Microplasmas have received growing attention in many application driven fields, such as plasma medicine. In this field, helium is often used a buffer gas due to its excellent thermal properties and traces of oxygen and/or water vapor are typically introduced the feed create reactive species interest for biomedical applications. Here we consider atmospheric pressure He+H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML"...