Article
Physics, Fluids & Plasmas
G. Pokrovskiy, N. A. Popov, S. M. Starikovskaia
Summary: This study investigates the fast gas heating in a pulsed nanosecond capillary discharge in pure CO2 under the conditions of high specific deposited energy and high reduced electric fields. Experimental measurements of specific deposited energy, reduced electric field, and gas temperature as functions of time are conducted. The radial distribution of the electron density is analyzed experimentally. Numerical modeling in the framework of 1D axial approximation is used to analyze the quenching effect of excited atoms and molecules, leading to heat release at a sub-microsecond time scale.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2022)
Article
Materials Science, Ceramics
Yihan Liang, Siqi Xiang, Xinfang Zhang
Summary: In this study, a novel configuration for ultrafast high-temperature heating in air using commercial graphite paper is presented. This configuration enables stable high temperatures and ultrafast heating rates. By considering different heating profiles, ultrafast high-temperature sintering with tunable microstructures is demonstrated.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2022)
Article
Physics, Applied
Yutai Li, Yangyang Fu, Zhigang Liu, Peng Wang, Xiaobing Zou, Xinxin Wang
Summary: The phenomenon of polarity reversal was observed in the nanosecond pulse breakdown experiment. Energetic electrons were found to be generated during the positive polarity discharge and contribute significantly to the rapid breakdown of the air gap.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Physics, Fluids & Plasmas
Chenjie Li, Xinlei Zheng, Yifeng Wang, Shuhan Liu, Zheng Zhao, Jiangtao Li
Summary: This paper investigates the impact of pulse rise time on the temporal evolution of electron energy and density under repetitive nanosecond pulses in atmospheric nitrogen with 100 ppm oxygen impurities using a two-dimensional particle-in-cell/Monte Carlo collision model. The study finds that the peak value of mean electron energy increases with decreasing pulse rise time in single pulsed discharge, but shows a saturation trend in repetitive pulsed discharge approximated by pre-ionization. The time required for the mean electron energy to reach its peak is approximately equal to the pulse rise time, regardless of the presence of pre-ionization. The presence of pre-ionization enhances the tracking ability of the mean electron energy to the pulse waveform during the pulse rise edge.
PHYSICS OF PLASMAS
(2023)
Article
Optics
Y. Chew, T. Tomita, T. P. Mahesh, S. Sugawa, S. de Leseleuc, K. Ohmori
Summary: Rydberg atoms show promise for ultrafast quantum operations, but strong interactions between single atoms have been challenging to harness. The authors introduce novel techniques to trap and cool atoms, and use laser pulses to excite them to a Rydberg state. Ultrafast energy exchange and conditional phase are observed.
Article
Chemistry, Multidisciplinary
Weiyin Chen, John Tianci Li, Zhe Wang, Wala A. Algozeeb, Duy Xuan Luong, Carter Kittrell, Emily A. McHugh, Paul A. Advincula, Kevin M. Wyss, Jacob L. Beckham, Michael G. Stanford, Bo Jiang, James M. Tour
Summary: Flash Joule heating (FJH) has been utilized to synthesize different fluorinated carbon allotropes including fluorinated nanodiamonds, fluorinated turbostratic graphene, and fluorinated concentric carbon in a solvent-free manner. The modification of electronic states and the presence of various short-range and long-range orders in these fluorinated carbon allotropes have been confirmed through spectroscopic analysis. The relationship between flash time and phase evolution as well as product compositions has been further demonstrated.
Article
Chemistry, Physical
Vanesa Manzaneda-Gonzalez, Kellie Jenkinson, Ovidio Pena-Rodriguez, Olivia Borrell-Grueiro, Sergio Trivino-Sanchez, Luis Banares, Elena Junquera, Ana Espinosa, Guillermo Gonzalez-Rubio, Sara Bals, Andres Guerrero-Martinez
Summary: Metal nanocrystals with unique physicochemical features are widely used in catalysis, optical materials, and biomedicine. This study presents a synthetic method for fabricating hollow multimetallic heterostructures using a combination of seed-mediated growth routes and femtosecond-pulsed laser irradiation. The synthesized nanocrystals exhibit multihollow anisotropic structures, which offer attractive prospects for the fabrication of tailored high-entropy alloy nanoparticles.
CHEMISTRY OF MATERIALS
(2023)
Article
Thermodynamics
Yage He, Xianshuang Wang, Yeping Ren, Pengwan Chen, Yugui Yao, Rui Liu, Ruibin Liu
Summary: The Al/PTFE reactive material shows potential applications in defense and military, and its microscopic reaction process has been investigated through laser-induced plasma spectroscopy and high-speed schlieren photographs. Different plasma chemistry and combustion behavior of microscale Al/PTFE from pure Al have been observed, and a qualitative reaction model has been proposed to describe the response and combustion behavior. This study provides support for the application of these insensitive reactive materials in laser ignition.
COMBUSTION AND FLAME
(2023)
Article
Thermodynamics
Ammar M. Alkhalifa, Abdulrahman Alsalem, Davide Del Cont-Bernard, Deanna A. Lacoste
Summary: This study investigated the use of nanosecond repetitively pulsed (NRP) glow discharges to mitigate thermoacoustic fluctuations. Two strategies, continuous forcing and closed-loop gated forcing, were compared and found effective in reducing thermoacoustic fluctuations in a wall-stabilized methane-air flame. A parametric study was conducted to analyze the impact of various factors on the performance of the plasma actuator. The study also utilized phase-locked imaging to observe the oscillations in the flame's base location and surface area and demonstrated the stability achieved with the optimal discharge forcing.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Engineering, Electrical & Electronic
Yury D. Korolev, Nikolay V. Landl, Oleg B. Frants, Vladimir G. Geyman, Grigoriy A. Argunov, Pavel V. Logachev, Petr A. Bak, Alexander V. Akimov
Summary: This article describes the modified version of a commercially produced pseudospark switch and its testing results, which aimed to achieve nanosecond triggering stability for multiple switches connected in parallel to a common load. The results showed that the modified switch had low triggering delay time and jitter.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2021)
Article
Physics, Fluids & Plasmas
Xiancong Chen, Yifei Zhu, Yun Wu, Jinbo Hao, Xiaoguang Ma, Pengfei Lu
Summary: In this study, single-pulse nanosecond surface dielectric barrier discharges operated in synthetic air and pure nitrogen at elevated pressure were numerically studied to provide a basis for analyzing the surface streamer-to-filament transition phenomenon. The electrical parameters, discharge morphology, and propagation dynamics at elevated pressure were discussed in detail, showing good agreement between measurement, numerical simulation, and analytical estimation. The study revealed that the streamer thickness is inversely proportional to pressure, with the average reduced electric field in the streamer channel ranging from 75-150 Td and the average electron density for both polarities being around 10^(22) m^(-3).
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2021)
Review
Chemistry, Physical
Leo Lai, Jing Li, Yeyu Deng, Zixun Yu, Li Wei, Yuan Chen
Summary: Ultrafast heating methods have been used to synthesize novel carbon materials and carbon/metal hybrid structures with unique properties. This article reviews recent findings in this field, including the most frequently used methods, the different carbon structures created, and the synthesis processes of carbon/metal hybrid structures. The applications and challenges of these methods for scalable material production are also discussed.
Article
Physics, Fluids & Plasmas
Thibault Darny, Gerard Bauville, Michel Fleury, Stephane Pasquiers, Joao Santos Sousa
Summary: This paper investigates the modification of argon flow in a cold plasma jet under the influence of nanosecond high voltage pulses, examining both single and multiple pulse applications. The research shows that a single pulse is sufficient to disrupt the flow, with multiple pulses revealing a 3D helical arrangement of ripples in the plasma plume. Optimal disturbance of the flow is achieved at specific pulse repetition frequencies for different flow rates, with higher frequencies leading to the gradual disappearance of ripples.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2021)
Review
Clinical Neurology
Catarina da Silva Lourenco, Marleen C. Tjepkema-Cloostermans, Michel J. A. M. Van Putten
Summary: This study applies deep learning algorithm to automate detection of interictal epileptiform discharges (IED) in ambulatory EEGs. The algorithm achieved a 97% agreement with expert review and significantly reduced review time by 50-75 times.
CLINICAL NEUROPHYSIOLOGY
(2023)
Article
Chemistry, Physical
Feng Xu, Yanping Zhou, Xingwu Zhai, Hongjian Zhang, Haodong Liu, Edison Huixiang Ang, Yufei Lu, Zhentao Nie, Min Zhou, Jixin Zhu
Summary: A novel joule heating mechanism is proposed in this study to fabricate MOC nanosheets about 5 nm in thickness with tunable metal compositions. The method uses only a small amount of water as the solvent, and achieves fast heating through microwave and ionic conduction loss to produce Co-MOC nanosheets with superior lithium storage performance.
Article
Thermodynamics
Deanna A. Lacoste
Summary: Non-equilibrium plasma discharges can provide a favorable environment for combustion processes at low energy cost. This paper reviews recent progress in plasma-assisted combustion, with a focus on flame dynamics. Different plasma discharges and their effects on flame properties are presented, and the influence of these plasmas on the coupling between flames and acoustic waves is discussed. The shift towards favoring a chemical impact in plasma actuation is explained, and future research directions are proposed.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Physics, Fluids & Plasmas
Hongtao Zhong, Xin Yang, Xingqian Mao, Mikhail N. Shneider, Igor Adamovich, Yiguang Ju
Summary: This study investigates the stability of plasma in reactive mixtures, focusing on the thermal-chemical instability triggered by dimethyl-ether (DME) low-temperature oxidation. Through experimental exploration and theoretical analysis, the dynamics and chemical origin of the instability are revealed, providing insights for future control of plasma uniformity.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2022)
Article
Thermodynamics
Samir B. Rojas Chavez, Karl P. Chatelain, Deanna A. Lacoste
Summary: This experimental study presents a proof-of-concept for measuring the induction zone length (⠂i) in H2-air detonations using laser-induced fluorescence (LIF) of nitric oxide (NO). The proof-of-concept is demonstrated through experiments in an optical detonation duct and numerical simulations. The results show a correlation between the NO-LIF signal evolution and ⠂i, with a theoretical accuracy of 2% and an experimental uncertainty of ±160-±μm. While a correlation between the induction length and cellular cycle could not be achieved due to imaging limitations, the experimental induction lengths correlate well with the simulations.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Thermodynamics
B. Aravind, Vigneshwaran Sankar, Deanna A. Lacoste
Summary: The study focuses on the synthesis and analysis of low frequency flame oscillations in a Rijke tube combustor under external acoustic forcing. It is found that the system enters lock-in synchronization when the forcing frequency is in the range of 0.97 < ff / fn < 1.03 at a forcing amplitude of 10%, which results in quenching of the natural mode of the flame. Strong flame beating is observed on either side of this synchronization region. The flame transfer function (FTF) at the beating frequency is estimated and exhibits different behavior on either side of the synchronization region.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Energy & Fuels
Sagar Pokharel, Albina Tropina, Mikhail Shneider
Summary: In this study, a mathematical model was developed and numerical simulations of laser heating and evaporation of a single droplet in the diffusion-dominated regime were conducted using OpenFOAM software, taking into account the absorption of laser radiation, evaporation process, and vapor flow dynamics. The developed solver was validated against experimental and numerical data for heating and evaporation of ethanol and water droplets. It was found that for continuous laser heating, larger droplets exhibited higher peak temperatures, while for pulsed laser heating, the temporal dynamics of droplet temperature were independent of droplet size when the peak irradiance was close to the boiling regime.
Article
Energy & Fuels
Nader N. N. Shohdy, Mhedine Alicherif, Deanna A. A. Lacoste
Summary: This paper focuses on evaluating the effects of different levels of ammonia cracking on the overall burning velocity, lean blow-off limit, concentration of pollutants, and flame response to sound disturbances. Various ratios of cracked ammonia were experimentally investigated, and the results indicate that while ammonia cracking can improve the lean blow-off limit and burning velocity, it also leads to detrimental effects on pollutant emissions and flame stability, even at a low cracking percentage of 20%. Proposals for the reasons behind these results are provided based on flame dynamics analysis.
Article
Physics, Fluids & Plasmas
Albina Tropina, M. N. Shneider, R. B. Miles
Summary: A kinetic model of a non-equilibrium water vapor plasma created by a nanosecond pulsed discharge at elevated temperatures and at low pressure is presented. Simulation results show good agreement with experimental data, revealing that the decay of plasma in pure water vapor is controlled by dissociative recombination and the formation of vibrationally excited species can be observed.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2022)
Article
Physics, Applied
Mikhail N. Shneider, Yevgeny Raitses, Shurik Yatom
Summary: This paper presents a theory of electron photo-detachment from charged metallic nanoparticles, which is relevant to the measurement of nanoparticle charge in plasmas using laser stimulation. The study shows that the charging of nanoparticles in plasma leads to the appearance of an additional electric field, causing a change in the potential barrier at the particle boundary and a change in the effective work function due to the Schottky effect. In this case, the critical wavelength of the laser depends not only on the work function but also on the charge and size of the nanoparticles.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2023)
Article
Mechanics
Zehua Liu, Kentaro Hara, Mikhail N. Shneider
Summary: A shallow water model that considers surface tension and electric field effects is developed to study the dynamics of an electrified liquid surface. The model is verified against the Zakharov-Kuznetsov equation and applied to analyze the growth and damping of the electrified liquid surface. The electrified liquid surface grows or dampens depending on the balance of electric field, surface tension, and gravitational forces. The numerical results obtained from the model are in good agreement with the theoretical analysis.
Article
Physics, Fluids & Plasmas
Nicolas Q. Minesi, Pierre B. Mariotto, Erwan Pannier, Axel Vincent-Randonnier, Gabi Daniel Stancu, Christophe O. Laux
Summary: This study focuses on the formation of fully ionized plasmas in ambient air by nanosecond pulsed discharges, called thermal spark. The article first presents experimental characterization of the electron number density during the pulse, showing an increase up to 10^19 cm^-3 with sub-nanosecond resolution using three techniques based on optical emission spectroscopy. The study also develops a 0D kinetic mechanism to explain the observation, highlighting the importance of excited state kinetics in the thermal spark formation.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2023)
Article
Physics, Fluids & Plasmas
A. Yu Starikovskiy, N. L. Aleksandrov, M. N. Shneider
Summary: The study performed a numerical analysis on plasma generation by a nanosecond pulsed discharge in a strong magnetic field. A 2D model of the plasma formation and decay in magnetohydrodynamic channel was developed. The comparison with experimental results showed good agreement between calculated and measured plasma distribution in the channel. Preliminary analysis indicated a high energy efficiency of the MHD-generator based on nanosecond dielectric barrier discharge flow pre-ionization, making it a promising concept for energy generation and flow control.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2023)
Article
Mechanics
K. P. Chatelain, S. B. Rojas Chavez, J. Vargas, D. A. Lacoste
Summary: This study validates the new developments in the in-house spectroscopic code (KAT-LIF) for NO-LIF simulations under detonation conditions and evaluates the diagnostic capabilities of NO-LIF for characterizing H2-air detonations. The study involves updating KAT-LIF with a database of NO(A-X) transitions and implementing species-specific parameters for NO-LIF simulations. The validation of KAT-LIF is performed by comparing simulation results with pre-existing tools (LIFSim and LIFBASE) and experimental measurements, showing satisfactory agreement.
Article
Radiology, Nuclear Medicine & Medical Imaging
Mikhail N. Shneider, Mikhail Pekker
Summary: This study presents a simple theoretical model that blocks the transmission of signals from sensory neurons, affecting anesthesia without the use of anesthetics using a sequence of unipolar current pulses generated externally. The proposed model allows for parameter selection and the required frequency of current pulse repetition to achieve anesthesia, depending on the electrical characteristics of the skin and the conductivity of the saline solution in which myelinated nerve fibers are located.
BIOMEDICAL PHYSICS & ENGINEERING EXPRESS
(2023)
Correction
Physics, Applied
Mikhail N. Shneider, Yevgeny Raitses, Shurik Yatom
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2023)
Article
Thermodynamics
Joao Vargas, Manuel Monge-Palacios, Deanna A. Lacoste
Summary: This study provides necessary data support for planetary probe missions by calculating the reaction rate constants involving molecular hydrogen.
JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER
(2023)
