Search

This Perspective paper deals with an overview of particle-in-cell/Monte Carlo collision models applied to different plasma-propulsion configurations and scenarios, from electrostatic (E × B and pulsed arc) devices to electromagnetic (RF inductive, helicon, electron cyclotron resonance) thrusters, as well as plasma plumes and their interaction with the satellite. The most important items related to the modeling of plasma–wall interaction are also presented. Finally, the paper reports new progress in the particle-in-cell computational methodology, in particular, regarding accelerating computational techniques for multi-dimensional simulations and plasma chemistry Monte Carlo modules for molecular and alternative propellants. [ABSTRACT FROM AUTHOR]

Blebs collaborate with other protrusion types for cell motility, sharing common initiation mechanisms. Asymmetric distribution of membrane-cortex linkers and polarized contractility, regulated by signaling pathways and small GTPases, govern front–rear polarity. The bleb formation–retraction cycle, influenced by membrane-cortex coupling dynamics, leads to various blebbing regimes: transient, circus, and stable. Cortical flows drive cell locomotion by establishing global polarity and generating propulsion forces in bleb-based migration. Blebs facilitate very diverse migration strategies and environmental interactions through mechanisms such as integrin or cadherin-mediated adhesions or nonspecific friction. Bleb-based migration, a conserved cell motility mode, has a crucial role in both physiological and pathological processes. Unlike the well-elucidated mechanisms of lamellipodium-based mesenchymal migration, the dynamics of bleb-based migration remain less understood. In this review, we highlight in a systematic way the establishment of front–rear polarity, bleb formation and extension, and the distinct regimes of bleb dynamics. We emphasize new evidence proposing a regulatory role of plasma membrane-cortex interactions in blebbing behavior and discuss the generation of force and its transmission during migration. Our analysis aims to deepen the understanding of the physical and molecular mechanisms of bleb-based migration, shedding light on its implications and significance for health and disease. [ABSTRACT FROM AUTHOR]

The evaluation of the impact of plasma-facing units (PFUs) damage on subsequent plasma operation is an important issue for ITER. This is one of the topic addressed by the operation of dedicated PFUs in WEST. From the start of WEST in 2017, few ITER grade divertor PFUs were tested in the lower divertor for short plasma exposure (experimental campaigns C1–C5). A PFU is an assembly of tungsten blocks on CuCrZr tube via pure copper interlayer. Since 2022, WEST operates with a lower divertor fully equipped with ITER grade PFUs (experimental campaign C6–C7) with long duration plasma exposure capabilities. To test the ageing of the ITER-grade PFUs on an accelerated basis, well controlled damage was implemented on purpose with electron beam loading on the plasma facing surface of two different PFUs (pre-damage#1 and #2 featuring different level of damage). Damage tackled in this study is induced by the loading with numerous transient heat loading events to mimic the ELM impact on the ITER grade PFU. This paper presents the damage before and after WEST plasma exposure and shows the tungsten sources and temperature of the block measured during the operation. On damaged area, surface roughening is heterogeneous. With WEST campaigns (C3, C4 and C7) respectively ended in (2018, 2019 and 2023) a global smoothing of the pre-damaged surfaces, in particular those located in the high loaded erosion area, is observed. No evolution of the crack is observed in the electron beam loaded area, while new cracking are observed on non pre-damaged area on the tungsten top surfaces in highly loaded areas (outer strike point) after significant plasma duration and cumulated energy (first observation in C4 and tends to be confirmed with preliminary observations after the C7 campaign). Smoothing is less pronounced after the 2018 campaign, which may be due to the related short plasma duration. The surface smoothing of blocks also depends on their poloidal position. For PFU which has no shaping, toroidal positioning within a block has no influence on the surface smoothing. After 2019 and 2023 campaigns, equivalent relative smoothing is obtained (between 19 and 32%). For the explored plasma conditions, damage has no influence on the maximum brightness of W. [ABSTRACT FROM AUTHOR]

Explosive electron emission splashes occurring in plasma interactions with nanostructured surfaces can be induced by Joule energy release under reduced conductivity. Distribution of helium nanobubbles inside tungsten at an elevated energy of implanted helium ions has been studied via numerical molecular dynamic modeling, and its impact on the nanostructure conductivity has been estimated. Average concentration and size of nanobubbles were calculated to be about n = 1020 cm−3 and r = 3 Å, respectively, at the helium fluence of about 2 × 1015 cm−2. The distribution of nanobubbles becomes more flat and extends deeper into the bulk material with increasing impact energy. At energies below about 300 eV, most nanobubbles form within a depth of 10 nm, corresponding to the characteristic size of the nanowires. At higher energies, a significant portion of the nanobubbles forms deeper in the material. An approach for estimating the electron scattering frequency in tungsten by helium nanobubbles has been proposed, taking into account the volume porosity of the W-fuzz nanostructure and scaling the helium content to the experimentally measured one. The resulting value for the tungsten fuzz nanostructure was 2.27 × 1016 s−1 and the resistivity was 1.92 mΩ cm that is 364 times larger than the normal tungsten resistivity, the conductivity of 521 S/cm was 0.275% from the normal tungsten one. The corresponding estimation of thermal conductivity via Wiedemann–Franz law gave 3.8 mW cm−1 K−1, which agrees well with recent measurements. [ABSTRACT FROM AUTHOR]

This work explores microcombustion technologies enhanced by plasma-assisted combustion, focusing on a novel simulation model for a Y-shaped device with a non-premixed hydrogen-air mixture. The simulation integrates the ZDPlasKin toolbox to determine plasma-produced species concentrations to Particle-In-Cell with Monte Carlo Collision analysis for momentum and power density effects. The study details an FE-DBD plasma actuator operating under a sinusoidal voltage from 150 to 325 V peak-to-peak and a 162.5 V DC bias. At potentials below 250 V, no hydrogen dissociation occurs. The equivalence ratio fitting curve for radical species is incorporated into the plasma domain, ensuring local composition accuracy. Among the main radical species produced, H reaches a maximum mass fraction of 8% and OH reaches 1%. For an equivalence ratio of 0.5, the maximum temperature reached 2238 K due to kinetic and joule heating contributions. With plasma actuation with radicals in play, the temperature increased to 2832 K, and with complete plasma actuation, it further rose to 2918.45 K. Without plasma actuation, the temperature remained at 300 K, reflecting ambient conditions and no combustion phenomena. At lower equivalence ratios, temperatures in the plasma area consistently remained around 2900 K. With reduced thermal power, the flame region decreased, and at Φ = 0.1, the hot region was confined primarily to the plasma area, indicating a potential blow-off limit. The model aligns with experimental data and introduces relevant functionalities for modeling plasma interactions within microcombustors, providing a foundation for future validation and numerical models in plasma-assisted microcombustion applications. [ABSTRACT FROM AUTHOR]

Plasma–liquid systems are best recognised in biomedicine, where the generation of plasma‐treated water and complex organic‐containing solutions affords biological effects. However, plasma interactions with liquids are more diverse. In this review, we look from the chemical point of view at the three fields of plasma–liquid interaction in which plasma is used to convert organic substrates. In wastewater treatment, plasma decomposes organic substances: the selectivity towards specific products is less crucial than process energy costs. In the conversion of organic liquids for sustainable energy purposes, the carbon and hydrogen selectivity to syngas are important, but these are still destructive reactions yielding small molecules. Finally, we provide a comprehensive plasma application list for synthetic organic chemistry and discuss their mechanisms and limitations. [ABSTRACT FROM AUTHOR]

The availability of high-power lasers open new frontiers of Terahertz (THz) optics. In this paper, we present a mechanism for the enhanced THz field generation from the laser wakefield excitation during the interaction of an amplitude-modulated laser filament with a magnetized plasma. The derivation of electric and magnetic wakefields in axially magnetized plasma is obtained using the perturbative approach. Amplitude-modulated laser filament generates a significantly stronger transverse current due to laser intensity redistribution by the amplitude modulation. The modulation index of the amplitude modulated laser pulse is used to control the transverse current at THz frequency. Fourfold enhancement takes place in THz field strength for higher values of the modulation index (0–0.4). Also, the conversion efficiency of this mechanism is estimated as 1 0 − 4 that can be enhanced for higher modulation index. Scaling laws are provided for controlling and optimization of generated THz field. This work may be crucial in exploring THz optical phenomena such as THz field-induced Kerr effects and many other nonlinear effects. [ABSTRACT FROM AUTHOR]

Cells crucially rely on the interactions of biomolecules at their plasma membrane to maintain homeostasis. Yet, a methodology to systematically quantify biomolecular organisation, measuring diffusion dynamics and oligomerisation, represents an unmet need. Here, we introduce the brightness-transit statistics (BTS) method based on fluorescence fluctuation spectroscopy and combine information from brightness and transit times to elucidate biomolecular diffusion and oligomerisation in both cell-free in vitro and in vitro systems incorporating living cells. We validate our approach in silico with computer simulations and experimentally using oligomerisation of EGFP tethered to supported lipid bilayers. We apply our pipeline to study the oligomerisation of CD40 ectodomain in vitro and endogenous CD40 on primary B cells. While we find a potential for CD40 to oligomerize in a concentration or ligand depended manner, we do not observe mobile oligomers on B cells. The BTS method combines sensitive analysis, quantification, and intuitive visualisation of dynamic biomolecular organisation. Methods to assess diffusion dynamics and oligomerisation of biomolecules remain scarce. Here, the authors present a brightness-transit statistics method to measure diffusion and oligomerisation simultaneously with high sensitivity, and they apply their approach to study the organisation of CD40. [ABSTRACT FROM AUTHOR]

Plasma‐activated mist (PAM) has seen increasingly widespread applications in areas such as surface disinfection and fog cultivation. The high‐resolution time diagnostics of ns pulse plasma interacting with micron‐sized droplets under high‐humidity conditions is challenging to achieve with existing experimental methods. This paper employs a global model to study the interaction between plasma and droplets, offering a detailed analysis of the plasma's transition from the gas phase to the liquid phase. It was discovered that in high‐humidity environments, hydrated ions become the predominant ion species. These acidic active substances in PAM droplets are the primary factors in the mist's ability to kill bacteria. The paper further examines how variations in droplet size and discharge voltage influence the PAM's activity. [ABSTRACT FROM AUTHOR]

The processes in far scrape‐off layer (SOL) and the plasma interaction with the first‐wall (FW) elements may notably affect the tokamak discharge, since they define fuel and impurity recycling, material erosion and redeposition, wall surface heating, etc. For a long time, the far SOL description in most plasma edge transport codes was insufficient or absent at all, and so particle and heat fluxes onto the FW (except divertor plates) were out of consideration. Recently some codes, for example, SOLEDGE and SOLPS‐ITER are upgraded allowing for the extension of the computational grid up to real walls and for corresponding account of the vacuum vessel shape and all in‐vessel elements. The new release of SOLPS‐ITER (the version 3.2.0) required a development of a new code data structure and new approach to numerical approximation of fluid equations compatible with unstructured non‐orthogonal computational grid. Intensive testing of the new code in different conditions is still required. In the present contribution, such a testing is performed for the EAST disconnected double null (DDN) L‐mode discharge. For the first time, the SOLPS‐ITER 3.2.0 modeling results with drifts and currents turned on are presented, and a comparison to former SOLPS‐ITER version (3.0.8) is performed. The far SOL transport and its effects on the discharge performance are studied by comparing the computational results obtained on several meshes which differ by their width in equatorial midplane. A single null (SN) one (with mesh width limited by distance to the secondary separatrix) was examined versus two DDN meshes (one with actual and one with artificially extended targets to make mesh wider) and a true unstructured (the widest) mesh. The notable difference in results obtained on different meshes appears in those places where plasma density does not vanishes at the computational domain boundaries. For the cases on true unstructured (the widest) mesh, the particle and heat fluxes onto central column, limiters, far SOL part of targets, dome umbrella and other EAST far SOL in‐vessel structures are calculated for the first time by SOLPS‐ITER, allowing assessment of the plasma interaction with those surfaces. [ABSTRACT FROM AUTHOR]

A 3D analysis of plasma wall interactions and global impurity transport for the edge localized mode suppression window in KSTAR during H-Mode discharges has shown that carbon erosion at the divertor plates is a strong function of the resonant magnetic perturbation (n = 1) coil current and relative phasing. The Generalized Perturbation Equilibrium Code was used to determine a realistic initial perturbed plasma equilibrium, and EMC3-EIRENE was used to calculate the resulting scrape-off layer plasma used in this study as a fixed background for the ERO2.0 plasma–material interaction model. The resulting transport leads to deposition of impurities along the targets positioned at the high-field side of the device. An attempt at calculating the resulting effective charge state has demonstrated a similar dependence on the perturbation coil current and has been able to determine a window for the experimentally observed values of Z eff by including contributions of all ionized carbon charge states and deuterium. [ABSTRACT FROM AUTHOR]

During the process of terahertz (THz) wave generation via femtosecond laser filamentation in air, as well as through the mixing of THz waves with externally injected plasma filaments, THz waves engage in interactions with the plasma. A characteristic feature of this interaction is the modulation of the THz radiation spectrum by the plasma, which includes the generation of THz spectral dips. This information is essential for understanding the underlying mechanisms of THz–plasma interactions or for inferring plasma parameters. However, a current debate exists on the number of THz spectral dips observed after the interaction, with different opinions of single versus multiple dips, thus leaving the interaction mechanisms still ambiguous. In this work, we retrospectively analyzed the experimental appearance of multiple dips in the THz spectrum and found that the current observations of such dips are predominantly a result of the water vapor absorption with a low spectral resolution. Additionally, we observed that altering the acquisition width of the temporal THz signal also influenced the dips' number. Hence, in future research, simultaneous attention should be paid to the following two aspects of THz–plasma interactions: (1) It is necessary to ensure a sufficiently wide time-domain window to accurately represent the spectral dip characteristics. (2) The spectral dips should be carefully distinguished from the water absorption lines before being further studied. On the other hand, for the case of a single dip in the THz spectrum, we also put forward a new viewpoint of the resonance between surface plasmon waves and THz waves, which should also be taken into consideration in future studies. [ABSTRACT FROM AUTHOR]

Current generation of ground based gamma-ray telescopes observed dozens of sources of photons above 100 TeV. Supernova remnants, pulsar wind nebulae, young stellar clusters and superbubbles are considered as possible sites of PeV-regime particles producing the radiation. Another possible source of PeV particles could be gamma-ray binary systems. In these systems, a strong relativistic outflow from a compact object (neutron star or black hole) collides with the dense wind from a massive companion early-type star. Gamma-ray binaries are observed from radio to high energy gamma-rays as luminous non-thermal sources. Apart from acceleration of very high energy leptons producing most of the non-thermal radiation, these systems may also efficiently accelerate protons. We present here the results of numerical simulation of the PeV-regime proton acceleration in gamma-ray binaries. The simulation is based on relativistic MHD modeling of local flows of magnetized plasma in the region of interaction of two colliding winds. We then inject 0.1 PeV protons into the system and directly follow their trajectories to demonstrate that they are accelerated to energies above PeV. High magnetization of the wind of the young massive star providing a Gauss range field in the winds interaction region is of paramount importance for the acceleration of protons above PeV. The maximum energies of protons accelerated by colliding winds in gamma-ray binaries can significantly exceed the energy of the pulsar potential's drop, which limits from above the energy of particles accelerated by an isolated pulsar. [ABSTRACT FROM AUTHOR]

Turbulent transport in magnetically confined fusion plasma has conventionally been analyzed at the ion gyroradius scale based on the microturbulence theory. However, ion-scale turbulence analysis sometimes fails to predict the turbulent transport flux observed experimentally. Microturbulence at the electron gyroradius scale and cross-scale interactions between disparate-scale turbulences are possible mechanisms to resolve this issue. This overview discusses the recent progress in multiscale turbulence studies and presents future perspectives from recent experimental, theoretical, and numerical investigations. The following aspects are highlighted: (1) the importance of electron-scale effects in experiments, (2) the physical mechanisms of cross-scale interactions, (3) modeling electron-scale effects in quasilinear transport models, and (4) the impacts of cross-scale interactions on burning plasmas. Understanding multiscale turbulence is necessary to improve performance prediction and explore optimal operations for future burning plasmas. [ABSTRACT FROM AUTHOR]

When a laser is focused on an underwater object, it experiences a large amount of pressure owing to the plasma confinement effect of water. A hemispherical bubble is generated on the surface of the object, and large pressure is generated when the bubble collapses. In this study, we conducted experiments using different laser energies to analyze the pressure–time histories associated with bubble contraction. The maximum pressure was 10%–40% of the laser ablation pressure, whereas the pressure pulse width was 5–10 times longer than the laser pulse width. Furthermore, the bubble motion could be adiabatically explained, except for the plasma interaction region. The results indicate that the pressure at which the bubble collapses does not depend on the maximum size of the generated bubble but depends on the energy of water vapor within the bubble. [ABSTRACT FROM AUTHOR]

Slits have been widely used in laser–plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle beams. Here, we propose and demonstrate that periodic thin slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser pulse. The fundamental physics of intense laser interaction with thin slits is studied, and it is revealed that relativistic effects can lead to enhanced laser focusing far beyond the pure diffractive focusing regime. In addition, the interaction of an intense laser pulse with periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared with conventional waveguides. These results provide a novel method for manipulating ultra-intense laser pulses and should be of interest for many laser-based applications. [ABSTRACT FROM AUTHOR]

Molecular probes with the ability to differentiate between subcellular variations in acidity levels remain important for the investigation of dynamic cellular processes and functions. In this context, a series of cyclic peptide and PEG bio-conjugated dual near-infrared emissive BF2-azadipyrromethene fluorophores with maxima emissions at 720 nm (at pH > 6) and 790 nm (at pH < 5) have been developed and their aqueous solution photophysical properties determined. Their inter-converting emissions and fluorescence lifetime characteristics were exploited to track their spatial and temporal progression from first contact with the plasma membrane to subcellular locales to their release within extracellular vesicles. A pH-dependent reversible phenolate/phenol interconversion on the fluorophore controlled the dynamic changes in dual emission responses and corresponding lifetime changes. Live-cell confocal microscopy experiments in the metastatic breast cancer cell line MDA-MB-231 confirmed the usability of the dual emissive properties for imaging over prolonged periods. All three derivatives performed as probes capable of real-time continuous imaging of fundamental cellular processes such as plasma membrane interaction, tracking endocytosis, lysosomal/large acidic vesicle accumulation, and efflux within extracellular vesicles without perturbing cellular function. Furthermore, fluorescence lifetime imaging microscopy provided valuable insights regarding fluorophore progression through intracellular microenvironments over time. Overall, the unique photophysical properties of these fluorophores show excellent potential for their use as information-rich probes. [ABSTRACT FROM AUTHOR]

In the inlet passage of a hypersonic vehicle, multi-channel shock waves inevitably interact with the boundary layer, producing complex multi-channel shock wave/boundary layer interactions (SWBLIs). The flow separation caused by these interactions significantly decreases the intake efficiency and may prevent the intake from starting. The typical interaction mode of multi-channel interactions is through double incident SWBLIs. Therefore, it is necessary to study the characteristics of double incident SWBLIs and identify relevant flow control techniques. In this paper, the characteristics of hypersonic double incident SWBLIs are first examined, and then the results of an experimental study on regulation using a plasma actuation array are reported. We find that plasma actuation can positively regulate the hypersonic double incident SWBLI, and the optimal control effect reduces the area of the separation bubble by 38.62%. The main regulation mechanism involves suppressing the low-frequency instability of SWBLIs through a high-frequency shock effect. The regional scale of the separation bubble can be controlled by regulating the shock wave oscillation range. Correlative results provide technical and method support for the application of plasma actuation in hypersonic double incident SWBLI regulation and present a new idea for the selection of flow control methods for advanced intake systems. [ABSTRACT FROM AUTHOR]

Dissipation processes derived from the kinetic theory of gases (shear viscosity and heat conduction) are employed to examine the solar wind that interacts with planetary ionospheres. The purpose of this study is to estimate the mean free path of wave-particle interactions that produce a continuum response in the plasma behavior. Wave-particle interactions are necessary to support the fluid dynamic interpretation that accounts for the interpretation of various features measured in a solar wind–planet ionosphere region; namely, (i) the transport of solar wind momentum to an upper ionosphere in the presence of a velocity shear, and (ii) plasma heating produced by momentum transport. From measurements conducted in the solar wind interaction with the Venus ionosphere, it is possible to estimate that in general terms, the mean free path of wave-particle interactions reaches λH ≥ 1000 km values that are comparable to the gyration radius of the solar wind particles in their Larmor motion within the local solar wind magnetic field. Similar values are also applicable to conditions measured by the Mars ionosphere and in cometary plasma wakes. Considerations are made in regard to the stochastic trajectories of the plasma particles that have been implied from the measurements made in planetary environments. At the same time, it is as possible that the same phenomenon is applicable to the interaction of stellar winds with the ionosphere of exoplanets, and also in regions where streaming ionized gases reach objects that are subject to rotational motion in other astrophysical problems (galactic flow–plasma interactions, black holes, etc.). [ABSTRACT FROM AUTHOR]

A comprehensive study of the interactions of human serum albumin (HSA) and α-1-acid glycoprotein (AAG) with two isoquinoline alkaloids, i.e., allocryptopine (ACP) and protopine (PP), was performed. The UV-Vis spectroscopy, molecular docking, competitive binding assays, and circular dichroism (CD) spectroscopy were used for the investigations. The results showed that ACP and PP form spontaneous and stable complexes with HSA and AAG, with ACP displaying a stronger affinity towards both proteins. Molecular docking studies revealed the preferential binding of ACP and PP to specific sites within HSA, with site 2 (IIIA) being identified as the favored location for both alkaloids. This was supported by competitive binding assays using markers specific to HSA's drug binding sites. Similarly, for AAG, a decrease in fluorescence intensity upon addition of the alkaloids to AAG/quinaldine red (QR) complexes indicated the replacement of the marker by the alkaloids, with ACP showing a greater extent of replacement than PP. CD spectroscopy showed that the proteins' structures remained largely unchanged, suggesting that the formation of complexes did not significantly perturb the overall spatial configuration of these macromolecules. These findings are crucial for advancing the knowledge on the natural product–protein interactions and the future design of isoquinoline alkaloid-based therapeutics. [ABSTRACT FROM AUTHOR]

This review focuses on an extensive synopsis of the recent improvements in CO2 hydrogenation over structured zeolites, including their properties, synthesis methods, and characterization. Key features such as bimodal mesoporous structures, surface oxygen vacancies, and the Si/Al ratio are explored for their roles in enhancing catalytic activity. Additionally, the impact of porosity, thermal stability, and structural integrity on the performance of zeolites, as well as their interactions with electrical and plasma environments, are discussed in detail. The synthesis of structured zeolites is analyzed by comparing the advantages and limitations of bottom-up methods, including hard templating, soft templating, and non-templating approaches, to top-down methods, such as dealumination, desilication, and recrystallization. The review addresses the challenges associated with these synthesis techniques, such as pore-induced diffusion limitations, morphological constraints, and maintaining crystal integrity, highlighting the need for innovative solutions and optimization strategies. Advanced characterization techniques are emphasized as essential for understanding the catalytic mechanisms and dynamic behaviors of zeolites, thereby facilitating further research into their efficient and effective use. The study concludes by underscoring the importance of continued research to refine synthesis and characterization methods, which is crucial for optimizing catalytic activity in CO2 hydrogenation. This effort is important for achieving selective catalysis and is paramount to the global initiative to reduce carbon emissions and address climate change. [ABSTRACT FROM AUTHOR]

The ring current, an equatorial near‐Earth current, fluctuates in response to solar wind plasma interactions with Earth's magnetosphere. Despite extensive research on storm‐time ring current energization, direct evidence of the energy transport into the inner‐magnetosphere that powers this current remains scarce. Recent observations revealing that very‐near‐Earth reconnection (VNERX, occurring at geocentric distance <14 RE) can occur during storms suggest that such reconnection could play an important role in ring current development. Here we address how common VNERX is. We use inner‐magnetosphere and plasma sheet observations from the Time History of Events and Macroscale Interactions during Substorms (THEMIS) satellites spanning 13 years. During this period, THEMIS observed 512 storms and 7 VNERX events. All VNERX events occurred during storm main‐phase at or near the pre‐midnight sector (None were observed during storm recovery‐phase.). The events occurred within 1 RE of the modeled neutral sheet, suggesting that VNERX events are elusive because they lie near the neutral sheet. Since THEMIS spent 5,253 hr within 1 RE of the modeled neutral sheet during storm main‐phase, the inferred observational VNERX occurrence rate is 1.3 per 1,000 hr of storm main‐phase. This rate is lower than published ion‐diffusion‐region occurrence rates seen in the near‐Earth plasma sheet during non‐storm times (likely substorms). These results suggest that while VNERX events might be significant for the storm‐time ring current's initial buildup (during storm main‐phase), other transport mechanisms, like enhanced global convection, may be responsible for maintaining the strength of the ring current during storm recovery‐phase. Key Points: Very‐Near‐Earth reconnection (VNERX) events have an observed occurrence rate of 1.3 events per 1,000 hr of storm main phaseVNERX may be important for the initial buildup of the main‐phase ring currentVNERX is predominately observed in the pre‐midnight sector [ABSTRACT FROM AUTHOR]

Based on graphical processing unit acceleration, a new method of finite‐difference time‐domain scheme is proposed to simulate the interaction between electromagnetic waves and magnetized plasma in two‐dimensional conditions. In this study, transversely electric and transversely magnetic are computed in time to avoid matrix operations involving Lorentz equations of motion. Compared to Young's method, the new method reduces addition and multiplication by about 63% and 66%, respectively. The simulation results of ionospheric wave propagation show that the new method agrees well with Young's method and the calculation speed is improved significantly. Plain Language Summary: Finite‐difference time‐domain (FDTD) has been widely used in electromagnetic waves propagation in plasma. FDTD method computation can be greatly accelerated by graphical processing unit (GPU). However, in magnetized plasma, the media information is described by a tensor, and the computing includes the complex matrix operation. Moreover, in nonlinear physical process, the complex operation brings a larger amount of computation. This shortage is more significant for multicore GPU with weaker single‐core computing power. Thus, it is essential to find new FDTD schemes to avoid the matrix operation and it is meaningful for both scientific calculation and engineering application. Key Points: We present a new two‐dimension finite‐difference time‐domain (scheme for wave propagation in and interaction with magnetized plasmaThe new method avoid complex matrix operation in solving couple of three velocities induced by Lorentz termThe method performance shows less operation and faster speed in computation, especially for multicore parallel computation with graphical processing unit [ABSTRACT FROM AUTHOR]

In situ FTIR transmission experiments for CO 2 and CO 2 – CH 4 plasma were performed for a fundamental study of surface plasma interaction with cerium oxide ( CeO 2 ) as catalytic surface. Utilizing a DC glow discharge plasma reactor at low pressure, it was observed that CO 2 gas adsorbs in the surface forming tridentate carbonates and hydrogen carbonates. When CO 2 – CH 4 plasma is ignited, formate species were formed while carbonate species disappeared from the surface. The CeO 2 pellet has also been placed downstream the plasma in order to observe the role of the gas composition at the exit of CO 2 – CH 4 plasma on CeO 2 without any heating or strong electric field. In addition, the effect of water was investigated in several surface phenomena. OH groups play an important role in the reaction with tridentate carbonates to generate formates under plasma. The gas phase chemistry of the CO 2 – CH 4 plasma used here has been described in details in the part I of this work. The conclusions drawn on the gas phase contribute to the understanding of the observed phenomena on CeO 2 . These results enlighten the complex mechanisms occurring during CO 2 – CH 4 plasma reactions on surfaces that could help in the improvement of CO 2 recycling. [ABSTRACT FROM AUTHOR]

Broadening of hydrogenic spectral lines is an important tool in spectroscopic diagnostics of various laboratory and astrophysical plasmas. We review recent analytical advances in three areas. First, we review the analytical solution for the splitting of hydrogenic lines under the combination of a circularly polarized electromagnetic wave with a strong magnetic field. Practical applications of this solution relate to the spectroscopic diagnostic of the electron cyclotron waves and to the relativistic laser–plasma interactions. Second, we review analytical results concerning the Stark–Zeeman broadening of the Lyman-alpha (Ly-alpha) line in plasmas. These results allow for the Stark width of the Ly-alpha π-component to be used for the experimental determination of the ion density or of the root-mean-square field of a low-frequency electrostatic plasma turbulence in the situation where the Zeeman effect dominates over the Stark effects. Third, we review recent analytical advances in the area of the intra-Stark spectroscopy: three different new methods, based on the emergent phenomenon of the Langmuir-wave-caused structures (“L-dips”) in the line profiles, for measuring super-strong magnetic fields of the GigaGauss range developing during relativistic laser–plasma interactions. We also review the rich physics behind the L-dips phenomenon – because there was a confusion in the literature in this regard.

This study reports on the influence of nitrogen plasma exposure of H‐diamond (100) on the adsorption of adventitious oxygen, nitrogen bonding, and thermal stability studied by X‐ray photoelectron spectroscopy. The nitrogen‐plasma exposures include microwave (MW) and radio frequency (RF) (at pressures: 3 × 10−2 (damaging) and 7 × 10−2 Torr (nondamaging)) nitrogen plasmas. The largest amount of oxygen ambient adsorption occurs on the damaging RF(N2) (O = 2.8 at%) exposed surface, whereas for MW(N2) (O = 0.8 at%) and nondamaging RF(N2) (O = 1.3 at%) exposed surfaces, a lower oxygen concentration is observed. Also, the highest level of structural damage to the upper atomic layers of the diamond is induced by exposure to the damaging RF(N2), followed by nondamaging RF(N2) and MW(N2). Thus, the near‐surface damage induced by the plasma interaction promotes adventitious oxygen adsorption (in various bonding configurations, including COx and C–NOx). For ambient‐exposed MW(N2)‐processed surface, nitrogen is adsorbed mainly in C–N/C=N state. Whereas for ambient‐exposed nondamaging‐ and damaging RF(N2)‐treated surfaces, nitrogen is bonded in mixed C–N/C=N and C≡N states alongside a small C–NOx component depending on the degree of surface defects. The damaging RF(N2)‐exposed surface exhibits a lower oxygen and nitrogen thermal stability than the other cases. [ABSTRACT FROM AUTHOR]

The interaction of an ambient air plasma with a water surface in a pin–water electrode configuration is presented in a polydiagnostic study. A discharge was generated by applying different high-voltage (HV) waveforms to a metallic pin electrode, positioned 2 mm above the water surface of a Petri dish filled with demineralized water. For pulsed discharge operation, a clear distinction is observed between a dielectric barrier discharge regime featuring a transient discharge at the rising as well as at the falling slope of the HV pulse, while a steady discharge is present in the gap during the complete HV pulse for the electrolysis regime. The occurrence of those two regimes is coupled to the increasing conductivity of the water over time, which additionally results in a quick rise of the dissipated discharge power and an increase of the gas temperature. The AC driven discharges exhibit only the electrolysis regime and do not significantly evolve over the treatment time. The resulting water conductivity was found to be a function of the total dissipated energy, irrespective of the discharge driving mode. Additionally, the resulting water conductivity shows a strong correlation with the total transferred charge in the gas phase. The total dissipated energy can potentially be used as a global measure to compare different experiments involving plasma–water interaction across different setups in different research groups. [ABSTRACT FROM AUTHOR]

The solar wind interacts with all solar system bodies, inducing different types of dynamics depending on their atmospheric and magnetic environments. We here outline some key open scientific questions related to this interaction, with a focus on the Moon and Mars, that may be addressed by future Mars and Moon missions by the European Space Agency's Human and Robotic Exploration programme. We describe possible studies of plasma interactions with bodies with and without an atmosphere, using multi-point and remote measurements, and energetic particle observations, as well as recommend some actions to take. [ABSTRACT FROM AUTHOR]

Achieving the potential for plasma particle interactions by modifying the Deutsch potential has been considered in many studies. One very convenient way to do this is to utilize the method as a dielectric function. In this method, by applying different potentials, it tries to provide corrective terms in the initial potential. As a result of using this method, an effective potential function is obtained from which the plasma characteristics including state equation and thermodynamic features can be derived. Because the screening effects between plasma particles are not taken into account by the Deutsch potential and therefore show different results from the real values, in this paper, we have tried to add corrective terms with the help of Hulthen potential and dielectric response function to it. Thus, an effective potential was obtained and then its equation of state was derived consequently. Finally, the results of this modified potential and the equation of state were compared with the results of other works. [ABSTRACT FROM AUTHOR]

The existence of even the simplest magnetized wormholes may lead to observable consequences. In the case where both the wormhole and the magnetic field around its mouths are static and spherically symmetric, and gas in the region near the wormhole falls radially into it, the former's spectrum contains bright cyclotron or synchrotron lines due to the interaction of charged plasma particles with the magnetic field. At the same time, due to spherical symmetry, the radiation is non-polarized. The emission of this just-described exotic type (non-thermal, but non-polarized) may be a wormhole signature. Also, in this scenario, the formation of an accretion disk is still quite possible at some distance from the wormhole, but a monopole magnetic field could complicate this process and lead to the emergence of asymmetrical and one-sided relativistic jets. [ABSTRACT FROM AUTHOR]

In an experiment performed on the Shenguang-III prototype laser facility, collective Thomson scattering (TS) is used to study the spatial growth of stimulated Brillouin scattering (SBS) in a gas-filled Hohlraum by detecting the SBS-driven ion acoustic wave. High-quality time-resolved SBS and TS spectra are obtained simultaneously in the experiment, and these are analyzed by a steady-state code based on the ray-tracing model. The analysis indicates that ion–ion collisions may play an important role in suppressing SBS growth in the Au plasma; as a result, the SBS excited in the filled gas region is dominant. In the early phase of the laser pulse, SBS originates primarily from the high-density plasma at the edges of the interaction beam channel, which is piled up by the heating of the interaction beam. Throughout the duration of the laser pulse, the presence of the TS probe beam might mitigate SBS by perturbing the density distribution around the region overlapping with the interaction beam. [ABSTRACT FROM AUTHOR]

Experimental investigations of n-butane oxidation under atmospheric-pressure plasma conditions and in He-dilution have provided detailed information on the power-dependence of the conversion of C 4 H 10 into CO and CO 2 at 450 K surface temperature. The rf-plasma discharge has been equipped with a MnO 2 -catalyst, and a significant impact on the reaction chain due to the presence of the catalyst surface could be observed. We report on ongoing data-based model development. Recently, a reaction kinetic model has been published, which agrees well with the experimental data (Stewig et al. in Plasma Sources Sci Technol 32:105006, 2023). However, that model could not clearly identify the main mechanisms in the interaction of plasma and catalyst. We show that various models can be found that explain the data similarly well. Detailed sensitivity analysis shows that only a maximum of three parameters can be identified in all the models considered for the currently limited data. Despite this limitation, we intend to continue the data analysis using more general models and introduce possible surface effects. Such unified models simultaneously describe the experimental data from both measurements with and without catalyst using a single set of physical parameters. To evaluate the hypotheses, we present numerical results for certain ranges of experimental parameters, which, in a subsequent experimental verification, allows to exclude or confirm one or another model. [ABSTRACT FROM AUTHOR]

In recent years, plasma biomedicine has developed into a new interdisciplinary subject. The interaction between plasma and organisms involves three aspects: "gas–liquid–living organisms." Molecular dynamics (MD) simulation can simulate the interaction process between plasma and biological tissue with high temporal and spatial resolution. This article reviews the research on plasma biomedicine based on MD simulation and systematically summarizes the progress of MD simulation research on the interaction between plasma and water layer, cell membrane, intracellular substances, extracellular environment, and viruses. These simulations offer a unique opportunity to gain insights into the microscopic mechanisms of these interactions. This article also further looks forward to the opportunities and challenges of MD simulation research. [ABSTRACT FROM AUTHOR]

This study focuses on constraining the role that Callisto's perturbed electromagnetic environment had on energetic charged particle signatures observed during the Galileo mission. To do so, we compare data from the Energetic Particle Detector (EPD) obtained during four close encounters of the moon with a model framework that combines hybrid simulations for low‐energy plasma and test‐particle tracing simulations for high‐energy particles. By comparing model results for energetic particle dynamics in both uniform and perturbed electromagnetic fields, we systematically disentangle the role that geometric effects (i.e., absorption of particles by Callisto's solid surface) have on observed energetic particle signatures compared to those associated with Callisto's perturbed electromagnetic environment (generated by the moon's induced magnetic field and plasma interaction currents). We show that observed flux drop‐outs in the energetic ion pitch angle distributions (PADs) are largely driven by their absorption by Callisto's surface: their large gyroradii exceed the size of the moon, facilitating their impact onto the icy surface and preventing their detection by EPD. However, features observed in the energetic electron PADs can only be explained with an accurate representation of the moon's perturbed environment, since electrons closely follow the orientation of the electromagnetic fields. Our findings therefore illustrate the key role that the moon's induced field and magnetospheric plasma interaction have on the dynamics of energetic electrons, emphasizing the importance of accurately modeling Callisto's locally perturbed electromagnetic environment when attempting to interpret data from past and future encounters, including those anticipated from the upcoming JUICE mission. Plain Language Summary: Jupiter's moon Callisto is continuously exposed to a combination of low‐energy plasma and high‐energy charged particles. As the moon interacts with these populations, its local electromagnetic field environment becomes highly perturbed. During four Callisto encounters during the Galileo mission to Jupiter, a sensor onboard the spacecraft detected clear signatures of the high‐energy ions and electrons. To understand the degree to which Callisto's low‐energy plasma interaction affects these signatures, we systematically model the dynamics of energetic particles as they travel through various electromagnetic field configurations. We find that the energetic ion observations are not strongly affected by the perturbed fields, but instead can be understood in terms of the particles being absorbed by Callisto's solid surface. However, electrons are highly sensitive to the draped fields, and the Galileo observations can only be understood when considering the perturbed electromagnetic environment near the moon. Our results underscore the importance of accurately modeling Callisto's perturbed environment when hoping to understand energetic particle signatures observed during the upcoming JUICE mission. Key Points: We compare energetic charged particle data with a model to explain pitch angle distributions observed during four Galileo flybys of CallistoElectron flux drop‐outs are shaped by the perturbed fields associated with Callisto's induced field and magnetospheric plasma interactionObserved ion fluxes can be mainly explained through geometric considerations, with Callisto's surface shadowing particles from detection [ABSTRACT FROM AUTHOR]

This research helps to develop a novel and economical method for improving the extraction efficiency of oil and fully valorizing guava fruit processing industrial waste into biomaterial. Dielectric barrier discharge atmospheric (DBDA) plasma is a novel non‐thermal technology that has been widely used in the food processing field of research. In this study, the synergistic effect of microwave (MW) and DBDA plasma treatment under different treatment combinations on the modification of morphological and biochemical properties of the guava pomace powder on improving the efficiency of extraction of biomaterials has been investigated. The response surface model (RSM) model was then constructed using the experimental results of Box–Behnken Design (BBD) to obtain the optimal extraction conditions. The predicted optimal extraction conditions for the microwave power level of 600 W for a treatment time of 90 s under solvent extraction at 420 min; DBDA plasma treatment as 35 kV for 15 min and solvent extraction conditions were determined as 80°C for 360 min causing an increment of the oil yield up to 16.19% when extracted using solvent extractor with ethanol as a solvent. These results indicate that the DBDA plasma treatment previous to the extraction step extraction process can contribute to reducing the duration of extraction by 120 min. The obtained data indicate that the MW and DBDA plasma pre‐treatment before the extraction can reduce the extraction duration, increase the yield, and improve the nutritional quality and functional properties. [ABSTRACT FROM AUTHOR]

Resonance interaction of a laser wave at twice the upper hybrid frequency with plasma in an inhomogeneous magnetic field is analyzed. A linear dependence of the magnetic field on the coordinate along the direction of propagation of the laser pulse and fulfillment of the resonance condition at the center of the plasma layer are assumed. It is demonstrated that the laser wave decays into two upper hybrid plasmons accompanied by excitation of the Bernstein modes under such an interaction. The occurance of an electromagnetic wave at the upper hybrid frequency reflected from the plasma boundary is detected. The conclusion is drawn that the reflected wave is driven upon interaction of the Bernstein modes with the upper hybrid plasmons since the wave disappears in the case of a cold-plasma layer. The dependence of average energy gained by electrons upon development of instability on the gradient of the external magnetic field is investigated. [ABSTRACT FROM AUTHOR]

The breakdown process of capacitively coupled plasma (CCP) in the presence of a matching network is rarely studied, even though it is the indispensable part of the most laboratory and industrial devices of CCP. Based on the method of Verboncoeur, the solution method of the general "L"-type match circuit coupled with a particle-in-cell/Monte Carlo code is deduced self-consistently. Based on this method, the electrical breakdown process of CCP is studied. Both the plasma parameters and the electric parameters of the matching network during the breakdown are given and analyzed. In the pre-breakdown phase, the entire circuit can be considered as a linear system. However, the formation of the sheath during breakdown significantly enhanced the capacitance of the discharge chamber, which changed the electric signal amplitude of the external circuit. With the stabilization of plasma, the equivalent capacitance of CCP increases, which continues to change the electrical signal until the steady-state is reached. Accompanied by plasma stabilization is the appearance of high-order harmonics of discharge current caused by the gradually oscillating CCP capacitance. The breakdown characteristics can be obviously affected by the capacitance of the matching network. In the case of a breakdown zone, some breakdowns with special characteristics can be obtained by choosing the different capacitors. These works might be a reference for understanding the interaction between the plasma and the external circuit during the breakdown process and how to modulate the gas breakdown by controlling the external circuit. [ABSTRACT FROM AUTHOR]

The interaction of high-temperature plasma with the matter has several potential applications. This study generated laser-induced plasma through single and successive laser energy deposition. The lifetime of the plasma is of paramount importance in most practical applications. However, this cannot be achieved with a single high-energy pulse due to certain practical challenges. Therefore, we carried out experimental and numerical investigations on the successive laser energy deposition and demonstrated its importance compared to the single pulse energy deposition. It has been observed that during successive energy deposition, the absorption of energy from the second pulse is nonlinear, and the reason for such behavior is explained in this study. Due to the nonlinear absorption from the second pulse, this study aims to present the pulse-interval configuration between the successive pulses with which it can be effective for practical use. In this study, some interesting physical phenomena (generation of fourth-lobe and multiple shock waves) are observed during successive energy deposition when the pulse interval is 50 and 100 μ s. This study also adopted a new approach based on Maxwell's theory of momentum exchange between light and matter to provide a plausible explanation for the generation of the fourth-lobe. Finally, to understand the evolution of the laser-induced plasma, the volume and volumetric expansion rate are calculated, which can be useful in determining its lifetime and mixing rate with the surrounding medium. [ABSTRACT FROM AUTHOR]

In this work, we performed an integrated study on the physicochemical changes of graphene oxide (GO) during the drying process in terms of their biological effects on red blood cells (hemolysis) and interactions with human plasma (protein corona formation). GO in aqueous dispersion (GO-Disp) was dried exploring two procedures: using a vacuum system at room temperature (GO-VD) and lyophilization (GO-LP). The nanomaterials were well characterized by microscopic (TEM, SEM, and AFM), spectroscopic (FTIR, UV–Vis, Raman, and 13C NMR), and XRD techniques. The lyophilization process produced a nanomaterial with a three-dimensional porous macrostructure and the lowest oxidation degree. In contrast, the vacuum-drying process at room temperature provided a nanomaterial with a film-like macrostructure, presenting a higher oxidation degree as well as physicochemical properties more similar to those of GO-Disp. All of the nanomaterials adsorbed human plasma proteins; however, the protein adsorption was more selective for GO-Disp. GO-VD induced hemolysis of red blood cells in a lower concentration than GO-Disp and GO-LP, but the protein corona formation suppressed the hemolytic effect for all nanomaterials. Finally, our results indicate that the method applied to dry GO nanomaterials has a critical influence on their nanobiointeractions with cells and proteins, suggesting that more attention should be paid to biomedical applications and toxicological evaluations associated with these promising nanomaterials. [ABSTRACT FROM AUTHOR]

The interaction of dislocations with plasma Si in a laser-injected Si was studied comprehensively using a combination of in-situ and ex-situ heating experiments in 200 kV electron microscopes and in a high-voltage electron microscope (HVEM). When dislocations were observed at 200 kV, i.e. virtually in the absence of electron irradiation, no evidence of the interaction between dislocations and plasma Si was obtained even when the observation was carried out at temperatures as high as 1250°C. However, when observed at 1000 kV in an HVEM, definite evidence of interaction was obtained even when the observation was carried out at room temperature. It is concluded that a combination of laser injection and electron irradiation is essential for the interaction to take place. [ABSTRACT FROM AUTHOR]

A large-aperture pulse-compression grating is one of the key components for laser-driven inertial confinement fusion, and is extremely vulnerable to being damaged by volatile organic contamination during operation. Plasma cleaning technology is a prospective method for removing organic deposits on the surface of optical components. Dibutyl phthalate, a commonly used sealing material, is used as the contamination source in this study, and the method of reactive molecular dynamics is used to simulate the plasma-based removal process of organic contaminants. The effects of key plasma cleaning parameters are investigated, including the interaction time, particle incident energy, and reactive species. Different mechanisms of nitrogen and oxygen plasma interactions were investigated. The effect of plasma on chemical bond fracture was analyzed, and the synergistic effect of physical and chemical influences was considered. The decomposition pathways and removal mechanism of organic contaminants under different incident reactive species are proposed at the atomic level. [ABSTRACT FROM AUTHOR]

An overview of results concerning simulation of various processes which occur due to atomic bombardment of crystalline and amorphous solids is presented. With the use of original computational codes, the following data were obtained: reflection coefficients, projected energy losses and ranges of ions in solids, channeling data as well as sputtering yield and its dependence on incident angle of bombarding particles for Be–W and Ne–W combinations. Be, C, and W targets were studied as these are among the plasma-facing materials in tokamaks, including ITER. The emphasis was made on atom-target combinations which lack reliable experimental data. Experimental data on other materials were used to verify calculations. A significant influence of the interaction potential used on the simulation results is shown. The reviewed results are tied by a common subject a study of interaction of plasma ions and first-wall materials of a tokamak-reactor and also by a common method of study the use of an original computational code. [ABSTRACT FROM AUTHOR]

Various physical processes in association with magnetic reconnection occur over multiple scales from the microscopic to macroscopic scale lengths. This paper reviews multi-scale and cross-scale aspects of magnetic reconnection revealed in the near-Earth space beyond the general global-scale features and magnetospheric circulation organized by the Dungey Cycle. Significant and novel advancements recently reported, in particular, since the launch of the Magnetospheric Multi-scale mission (MMS), are highlighted being categorized into different locations with different magnetic topologies. These potentially paradigm-shifting findings include shock and foreshock transient driven reconnection, magnetosheath turbulent reconnection, flow shear driven reconnection, multiple X-line structures generated in the dayside/flankside/nightside magnetospheric current sheets, development and evolution of reconnection-driven structures such as flux transfer events, flux ropes, and dipolarization fronts, and their interactions with ambient plasmas. The paper emphasizes key aspects of kinetic processes leading to multi-scale structures and bringing large-scale impacts of magnetic reconnection as discovered in the geospace environment. These key features can be relevant and applicable to understanding other heliospheric and astrophysical systems. [ABSTRACT FROM AUTHOR]

Direct numerical simulation of compression ramp shock wave/boundary layer interaction controlled by plasma actuator array is performed to gain a comprehensive understanding of its control outcome and mechanism in this paper. The computation model adopts a 24-deg compression ramp at Mach number Ma∞ = 2.0, whose simulation setup all refers to the experimental reports. First, the plasma actuator array is introduced into the Navier–Stokes (N–S) equation by a heating source model, and the corresponding numerical validation is proved in detail. Then, the flow control effect of plasma actuator array is systematically revealed, including the wave drag reduction and flow separation suppression. The results show that the mean shock wave drag can be decreased by 15% and the characteristic length of separation bubble can be reduced by 28%. At last, a new shock wave/boundary layer interaction control mechanism, called as 3D structure reconstruction, is concluded to guide the compression ramp flow control. Namely, by manipulating the quasi-2D shock wave and separation bubble into a 3D structural morphology in spanwise direction, the overall negative effect induced by shock wave/boundary layer interaction can be mitigated. [ABSTRACT FROM AUTHOR]

In this paper, an investigation of the interaction of a surface-wave-sustained argon plasma torch with liquids is presented. The plasma is produced by an electromagnetic wave traveling along the plasma–dielectric interface, and at the same time, the plasma is a part of this waveguide structure. Because the interaction of the plasma torch with water (liquid) results in modifications of the properties of both the treated water and the plasma itself, a detailed study of the effects in both media is required. The results of the experimental investigation of a surface-wave-sustained argon plasma torch interaction with liquids show significant changes in the plasma parameters, such as the electron excitation temperature Te and the average rotation temperature Trot. In addition, mechanical waves are produced both in the meniscus surface and in the plasma torch by the interaction between the plasma torch (ionized gas with charged particles and electric field) and the liquid surface, which is different from the effects produced by a neutral gas jet on a liquid surface. As a result of the plasma–water interaction, the water's chemical and physical characteristics, such as the water conductivity, pH, and H2O2 concentration, are modified. As a possible application for water purification, the performed SWD treatment of model wastewater shows a significant variation in nitrate, ammonium, phosphate, and COD (chemical oxygen demand) concentration as a result of the treatment. [ABSTRACT FROM AUTHOR]

In the current study, bulk tungsten material surfaces are exposed to hydrogen, deuterium, and helium plasmas in the radiofrequency domain (13.56 MHz) at an input power of 250 W using the hollow-cathode configuration. The ejected material is collected on titanium substrates at various distances (from 6 mm up to 40 mm). Therefore, the exposed tungsten materials are investigated for surface changes (blister occurrence, dust formation, or nano-structuration), along with the crystallinity, depending on the plasma's exposure times (from 30 min up to 120 min for each plasma type). Also, the collected materials are analyzed (morphological, structural, and statistical investigations) for dust and dust film-like appearance. Plasma discharges are analyzed using two methods: optical emission spectroscopy, and single Langmuir probes, to emphasize the nature of the used plasmas (cold discharges, ~2 eV), along with the presence of tungsten emission (e.g., WI 406.31 nm, WI 421.31 nm) during the plasma lifetime. By using a dedicated protocol, a method was established for obtaining fusion-relevant tungsten surfaces in the hydrogen and deuterium plasma discharges. By using the implemented method, the current paper introduces the possibility of obtaining a new tungsten morphology, i.e., the dandelion-like shape, by using helium plasma, in which the W18O49 compound can be found. [ABSTRACT FROM AUTHOR]

The expanded Poincar'e-Lighthill-Kuo approach is used to explore the collision of Schamel type ion acoustic solitary waves. The phase shift, the most crucial characteristic, is calculated using specific solutions on the basis of the Schamel type Korteweg-de Vries equations. It has been revealed that, in given regime of physically acceptable conditions, the effects of electron confinement and superthermality have a significant influence in altering the phase shift. The results will be a valuable contribution to ongoing research on plasma waves interactions as well as to inquiries into a number of laboratory plasma experiments. [ABSTRACT FROM AUTHOR]

The Prediction of Adverse effects of Geomagnetic storms and Energetic Radiation project (PAGER) aims to provide a framework for space weather and related effects forecasts. One of the innovative concepts is to plug, downstream of the environment prediction models, an automatized chain evaluating both surface and internal charging to forecast a charging risk evaluation for spacecraft on GEO and MEO orbits. The evaluation of the internal charging risk induced by electrons of the radiation belts with an energy above ∼ 0.5 MeV, is carried out throughout an innovating approach, combining different charging models, downstream the environmental ones. The space weather forecast is provided by a simulation of the radiation belt performed with VERB-3D. Downstream, the charging analysis is mainly performed using SPIS-IC, the internal charging branch of the open-source SPIS software (Spacecraft Plasma Interaction Software). SPIS-IC requires the prior computation of the source terms of space charge and dose rates resulting from the transport of primary electrons through the spacecraft structure. This is done beforehand using a 3D direct Monte-Carlo approach. In addition, a simple and fast internal charging 1D code, ICOne has been developed and is also used to evaluate the internal charging risk, based on a semi-empirical deposition rule. The internal charging modeling chain is used to carry out on one hand an evaluation of the electrical risk on a satellite in MEO orbit surrounded by an environment simulated by the VERB-3D Fokker-Plank code, and on the other hand, to reproduce measurements of a charging event of GIOVE-A. [ABSTRACT FROM AUTHOR]