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Abstract—During the magnetotelluric studies in North Vietnam, simultaneous Phase Roll Out from Quadrant effect was detected in the behavior of impedance phases Zxy and Zyx at one of the sounding sites, CTH, in the Cam Thuy district, Thanh Hoa province. The investigation of this phenomenon has shown that it is accompanied by negative (directed upwards) components of the Umov–Poynting vector of electromagnetic energy flux in the entire range of the recorded periods of magnetotelluric variations. This energy flux direction remains unchanged when the initial coordinate system is rotated by angles of 45° and 60°. Another characteristic feature of this phenomenon is an unusual behavior of the apparent resistivity curves: the apparent resistivity magnitudes increase starting from a period of 200 s up to a period of 104 s, and this increase occurs practically along the asymptote. The analysis of the magnetotelluric field polarization and phase tensor asymmetry parameter (skew angle) β has shown that the section is characterized by significant three-dimensional (3D) distortions which manifest themselves by β values ranging between 20° and 90°. [ABSTRACT FROM AUTHOR]

This paper introduces an evaluation of the flux air gaps of Shunt Reactors (SRs) to effectively mitigate fringing and leakage fluxes along the height of the iron core. The assessment of these discretely distributed flux air gaps in SRs is a rigorous and challenging process. To define their exact number, the case of one flux air gap is analyzed and investigated to observe/simulate the influence of the flux density distribution and the leakage flux along the air gaps on the reactive power and the operation conditions of the SR. Based on that, to reduce leakage flux, a large flux air gap is divided into smaller ones. Initially, an analytic model is presented to define the main parameters of the SRs. Then, a finite element method is developed to simulate electromagnetic quantities, such as the magnetic flux density, leakage flux, and electromagnetic force. The obtained results can help manufacturers define the exact number of flux air gaps along the iron core of the SR. From that, a suitable technology can be given in manufacturing high voltage SRs applied to high or super high voltage transmission lines. [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel staggered least squares method for elliptic equations on polygonal meshes. Our new method can be flexibly applied to rough grids and allows hanging nodes, which is of particular interest in practical applications. Moreover, it offers the advantage of not having to deal with inf-sup conditions and yielding positive definite discrete problems. Optimal a priori error estimates in energy norm are derived. In addition, a superconvergent estimates in energy norm are also developed by employing variational error expansion. The main difficulty involved here is to show the L 2 norm error estimates for the potential variable, where duality argument and the superconvergent estimates are the key ingredients. The single valued flux over the outer boundary of the dual partition enables us to construct a locally conservative flux. Numerical experiments confirm the theoretical findings and the performance of the adaptive mesh refinement guided by the least squares functional estimator are also displayed. In this paper, we propose a novel staggered least squares method for elliptic equations on polygonal meshes. Our new method can be flexibly applied to rough grids and allows hanging nodes, which is of particular interest in practical applications. Moreover, it offers the advantage of not having to deal with inf-sup conditions and yielding positive definite discrete problems. Optimal a priori error estimates in energy norm are derived. In addition, a superconvergent estimates in energy norm are also developed by employing variational error expansion. The main difficulty involved here is to show the norm error estimates for the potential variable, where duality argument and the superconvergent estimates are the key ingredients. The single valued flux over the outer boundary of the dual partition enables us to construct a locally conservative flux. Numerical experiments confirm the theoretical findings and the performance of the adaptive mesh refinement guided by the least squares functional estimator are also displayed. [ABSTRACT FROM AUTHOR]

Numerical simulations of a magnetically shielded Hall effect thruster with a centrally mounted cathode are performed with an axisymmetric hybrid particle-in-cell/fluid code and are partially validated with experimental data. A full description of the plasma discharge inside the thruster chamber and in the near plume is presented and discussed, with the aim of highlighting those features most dependent on the magnetic configuration and the central cathode. Compared to traditional magnetic configurations, the acceleration region is mainly outside the thruster, whereas high plasma densities and low temperatures are found inside the thruster. Thus, magnetic shielding does not decrease plasma currents to the walls, but reduces significantly the energy fluxes, yielding low heat loads and practically no wall erosion. The injection of neutrals at the central cathode generates a secondary plasma plume that merges with the main one and facilitates much the drift of electrons toward the chamber. Once inside, the magnetic topology is efficient in channeling electron current away from lateral walls. Current and power balances are analyzed to assess performances in detail. [ABSTRACT FROM AUTHOR]

In this paper, an equivalent imperfect interface model of PN homojunction/ heterojunction of piezoelectric semiconductor for the multi-field coupled wave propagation is proposed firstly. PN junction is a special structure formed by the contact of two different types of doped semiconductors, which has been used extensively in semiconductor devices. Due to the gradient distribution of the electric potential and carrier concentration in PN junction of finite thickness, the reflection and the transmission will arise when the coupled waves propagate through PN junction. The effects of the PN junction on the wave propagation will be much more complicated by the accurate estimation. An equivalent imperfect interface model without thickness but with seven interface parameters is established to simulate the effects of PN junction which largely reduces the calculation cost. The numerical examples are provided and compared with the state transfer matrix method and the piecewise homogenization method. Energy flux of the reflected and transmitted waves are estimated, and the energy conservation is checked to verify reliability of the numerical results. [ABSTRACT FROM AUTHOR]

Our research focuses on examining the characteristics of thin accretiondisks encircling regular black holes. In this study, we investigate the important features of accretion disks surrounding Bardeen's regular black holes, which play a crucial rols in addressing the singularity issue. The horizon co figuration of rotating Bardeen black holes is analyzed in details, as well as tfus innermost stable circular orbits related to this spacetime. The primary goal to derive quantively the radiative flux, differential and spectral luminositics of the accretion disk. Within the pionafacte httyiemsaec.j cT=reh0tei.o 2pn.r imrdiuasikry.r Wigndoiatihln iians cttohcy ed ersrwpievcety iqfiuaeatdntytgistriavvceriltyiai ttsiohcpen arralfndidiaeintldiva, e apflacurcxtii, scdtuiiflrafnerlryed, nibctkiya'lt caaknludinm gi file parameter r* > 0 and fixing thise j = 0.2, our findings show that the correspondinrg accretion disk's luminosity exceeds that onk yredicted Oy the Kew metric ar identical value of spin pasameter (y = 0.2). Making the juxtaposition of Bardeen's black h0ole parameter r0* with the spin parameter j of the Kerr bslaccrkarhsotlieowserrreivisaclrtrhnatditnhea stpratcyestimnrenc-oirrrteastpionnadBinagidtos sthnebnloanr-kroytartlisncg. Binarcdreoens brlsaictkaihnolreasc, sicn. sroamnei scieirctari certain case, can imitate the Kerr spacetime. [ABSTRACT FROM AUTHOR]

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Using simulation by means of the finite difference method in the time domain (FDTD), we demonstrated that focal spots of different shape with respect to both intensity and energy flux form upon tight focusing of a Gaussian linearly polarized beam containing an optical vortex by a Fresnel zone plate and upon focusing of a Gaussian beam by a spiral zone plate. The most significant differences are observed for the topological charge equal three. The energy flux upon focusing of a Gaussian beam by a Fresnel zone plate has a ring distribution, while the distribution of intensity and energy flux upon beam focusing by a spiral zone plate has three local maxima, which corresponds to the spiral-zone-plate order. The petal structure of intensity (and the energy flux) changes to a ring distribution at a certain distance from the focus. [ABSTRACT FROM AUTHOR]

Global change is transforming Earth's ecological communities with severe consequences for the functions and services they provide. In temperate grasslands, home to a mesmerising diversity of invertebrates controlling multiple ecosystem processes and services, land-use intensification and climate change are two of the most important global-change drivers. While we know a lot about their independent effects on grassland biodiversity and ecosystem functioning, little is known about how these stressors interact. Moreover, most research on biodiversity change focuses on decreasing biomass or species richness, while a major aspect is commonly ignored - altered ecological interactions. This is problematic because these interactions represent and control many important ecosystem processes, such as predation, herbivory or decomposition. Networks of trophic interactions, so-called food webs, link the structure and functioning of ecological communities and unravel mechanistic relationships between environmental change, ecological communities and ecosystem multifunctionality - the ability of a system to simultaneously support multiple processes. Consequently, we need to study how ecological interactions and the food webs they comprise respond to environmental change and to multiple interacting global-change drivers. Fortunately, novel tools offer unprecedented opportunities in studying trophic interactions and their impact on ecosystem processes. In addition, we know far more about how global change impacts the aboveground world than its belowground counterpart. However, belowground communities are just as important for the overall functioning of terrestrial ecosystems. Thus, to comprehensively understand global-change impacts on temperate grasslands, we need to study above- and belowground multitrophic interactions and ecosystem processes together, also accounting for their interdependencies. Here, we propose to use the Global Change Experimental Facility (GCEF, Bad Lauchstadt, Germany) to study joint impacts of land-use intensity and climate change on above-belowground multitrophic interactions and ecosystem multifunctionality in a temperate grassland global-change experiment. We will combine novel approaches to assessing trophic interactions and basal-resource dependency with an innovative method to quantify energy flux through ecological interaction networks. We will disentangle separate and interactive effects of land use and climate change and unravel how global-change driven modifications in multitrophic interactions mechanistically translate into altered ecosystem processes and multifunctionality - above and below the ground. Combining a field-experimental approach with novel molecular and quantitative techniques will allow for a leap forward in our understanding of global-change impacts on temperate grasslands, which will be crucial to manage and conserve these important ecosystems. [ABSTRACT FROM AUTHOR]

Detailed pathway of wave energy exchange between the Pacific and Indian Oceans through the Indonesian archipelago for a wide range of wave frequency is investigated using a reduced gravity model with realistic coastline. The wave energy flux analysis that can be applicable for all latitudes in a linear shallow water system is adopted. The energy fluxes diagnosed from the model outputs for the incoming Rossby waves from the Pacific clearly indicate two major energy pathways to the Indian Ocean: one turning southward in the Halmahera Sea and reaches the Indian Ocean via the Banda Sea and the Timor Passage, and the other passing through the Makassar and Lombok Straits. The former route, however, is shifted to the western side of the island chain within the Banda Sea due to energy trapping around the island chain. It is also found that strong energy dissipation occurs along the northern coast of New Guinea when the incoming wave period is shorter than 1.5 years. In the case of the Kelvin waves from the Indian Ocean, it is found that the major energy pathway is through the Lombok and Makassar Straits to the Pacific Ocean. However, there appears another pathway along the eastern side of the Sulawesi Island in the Banda Sea to exit through the Molucca Sea only when the wave period is shorter than about one month. This secondary pathway makes it easier for the wave energy from the Indian Ocean to reach the western Pacific Ocean for the short-period waves. [ABSTRACT FROM AUTHOR]

Analysis of electron flux within and in between molecules is crucial in the study of real-time dynamics of molecular electron wavepacket evolution such as those in attosecond laser chemistry and ultrafast chemical reaction dynamics. We here address two mutually correlated issues on the conservation law of molecular electronic flux, which serves as a key consistency condition for electron dynamics. The first one is about a close relation between "weak" nonadiabaticity and the electron dynamics in low-energy chemical reactions. We show that the electronic flux in adiabatic reactions can be consistently reproduced by taking account of nonadiabaticity. Such nonadiabaticity is usually weak in the sense that it does not have a major effect on nuclear dynamics, whereas it plays an important role in electronic dynamics. Our discussion is based on a nonadiabatic extension of the electronic wavefunction similar in idea to the complete adiabatic formalism developed by Nafie [J. Chem. Phys. 79, 4950 (1983)], which has also recently been reformulated by Patchkovskii [J. Chem. Phys. 137, 084109 (2012)]. We give straightforward proof of the theoretical assertion presented by Nafie using a time-dependent mixed quantum–classical framework and a standard perturbation expansion. Explicitly taking account of the flux conservation, we show that the nonadiabatically induced flux realizes the adiabatic time evolution of the electronic density. In other words, the divergence of the nonadiabatic flux equals the time derivative of the electronic density along an adiabatic time evolution of the target molecule. The second issue is about the accurate computationability of the flux. The calculation of flux needs an accurate representation of the (relative) quantum phase, in addition to the amplitude factor, of a total wavefunction and demands special attention for practical calculations. This paper is the first one to approach this issue directly and show how the difficulties arise explicitly. In doing so, we reveal that a number of widely accepted truncation techniques for static property calculations are potential sources of numerical flux non-conservation. We also theoretically propose alternative strategies to realize better flux conservation. [ABSTRACT FROM AUTHOR]

The effects of external discharge parameters (applied RF power, operating pressure, and gas flow rate) on ion flux uniformity are investigated in a dual inductively coupled plasma. The ion fluxes and electron temperatures are measured using a Langmuir probe floated by a DC blocking capacitor based on the floating harmonic method. The RF power applied to the top antenna focuses on the total ion flux control throughout the chamber, while the power introduced to the bottom antenna can control the ion flux uniformity in the diffusion chamber. At high pressures, the local electron heating in the vicinity of the bottom antennas results in local maximum ionization, thereby increasing the ion flux near the chamber wall. Furthermore, the ion flux uniformity also can be affected by the gas flow rate and pressure because they are associated with the gas residence time and the electron heating region. A physical understanding of the effects of external discharge parameters on plasma uniformity is useful for optimizing plasma processes. [ABSTRACT FROM AUTHOR]

The design concept of microwave-assisted magnetic recording (MAMR) using the flux control (FC) effect has been proposed as a technology for hard disk drives (HDDs). In this type of MAMR, the magnetization of an in-gap device (FC device) is reversed against the gap field by spin-transfer torque, enhancing the amplitude and gradient of the recording field. In this paper, we study the magnetization dynamics of an FC device fabricated in the write gap of an HDD write head. The operation of the FC device is analyzed by measuring the temporal resistance change in the sub-nanosecond region. Reversal of the FC device becomes faster as the bias current is increased and can be completed by 0.5 ns after the transition of the write current. The experimental results are reproduced by micromagnetic simulations using a head model, confirming that the simulations correctly describe the magnetization dynamics of the actual device. The simulations show that the recording field gain by the FC device appears with little delay after the rise of the recording field and that the FC device operates effectively even at a fast write rate of approximately 3 Gbit/s. Furthermore, we demonstrate the effectiveness of boosting the bias current, which can realize both fast and reliable operation of the FC device. These results indicate that the FC device operates as designed and that MAMR using the FC effect is promising for extending the recording density of HDDs. [ABSTRACT FROM AUTHOR]

Electrical and calorimetrical measurements were performed to obtain insight into the energy transformation from input power to the power available for the plasma treatment of substrates in a diffuse coplanar surface barrier discharge used as plasma source and operated in air, N 2 , O 2 , and CO 2 at input power of up to 380 W. Overall input power and applied electrical power were measured, and a conversion of 90% was determined with a constant loss of 30 W for the operation of the control unit. Measurements of the temperature gradient were performed for the electrode oil cooling to identify the power loss due to cooling. With roughly 50% of the applied electrical power, it turned out to be the largest loss term. A ceramic passive thermal probe was used to determine the energy flux from the plasma to a substrate. Highest energy flux values were found to be about 500 mW / cm 2 using air as working gas. Conversion efficiencies from the available electrical power via discharge to the power used for substrate treatment of 50%–35% depending on the working gas (highest for air, lowest for CO 2) were determined. Investigation on the spatial expansion of the surface discharge showed a dependence of the energy flux from the distance above the electrode. The energy flux maximum shifts to larger distances if no oxygen is present in the working gas. [ABSTRACT FROM AUTHOR]

The p53 transcription factor is a key mediator in cellular responses to various stress signals including DNA repair, cell cycle arrest, and apoptosis. In this work, we employ landscape and flux theory to investigate underlying mechanisms of p53-regulated cell fate decisions. Based on a p53 regulatory network, we quantified the potential landscape and probabilistic flux for the p53 system. The landscape topography unifies and quantifies three cell fate states, including the limit cycle oscillations (representing cell cycle arrest), high p53 state (characterizing apoptosis), and low p53 state (characterizing the normal proliferative state). Landscape and flux results provide a quantitative explanation for the biphasic dynamics of the p53 system. In the oscillatory phase (first phase), the landscape attracts the system into the ring valley and flux drives the system cyclically moving, leading to cell cycle arrest. In the fate decision-making phase (second phase), the ring valley shape of the landscape provides an efficient way for cells to return to the normal proliferative state once DNA damage is repaired. If the damage is unrepairable with larger flux, the system may cross the barrier between two states and switch to the apoptotic state with a high p53 level. By landscape-flux decomposition, we revealed a trade-off between stability (guaranteed by landscape) and function (driven by flux) in cellular systems. Cells need to keep a balance between appropriate speed to repair DNA damage and appropriate stability to survive. This is further supported by flux landscape analysis showing that flux may provide the dynamical origin of phase transition in a non-equilibrium system by changing landscape topography. [ABSTRACT FROM AUTHOR]

A high-velocity impact-ignition testing system was used to study the dynamic response of brittle thermite projectiles impacting an inert steel target at velocities of 850 and 1200 m/s. The projectiles included consolidated aluminum and bismuth trioxide that were launched by a propellant driven gun into a catch chamber equipped with high-speed imaging diagnostics. The projectiles passed through a break-screen at the entrance to the chamber and either fragmented upon penetrating the break-screen or remained intact prior to impacting the steel target. In all cases, the projectiles pulverized upon impact, and a reacting debris cloud spreads through the catch chamber. At lower impact velocities, the fragmented and intact projectiles produced similar flame spreading rates of 217–255 m/s. At higher impact velocities, the intact projectile produced the slowest average flame spreading rate of 179 m/s because debris rebounding was limited by the length of the projectile and the resulting debris field was highly consolidated in the radial direction. In contrast, the fragmented projectile rebounded into a well dispersed debris cloud with the highest, 353 m/s, flame spreading rate. A kinetic energy flux threshold was proposed as a means for describing the shift in observed debris dispersion and flame spreading rates. A reactivity model was developed based on particle burn times using a computational fluid dynamics code that incorporated heat transfer and particle combustion in a multiphase environment to understand how the particle size influenced flame spreading. Results from the model show a trade-off between faster reactivity and increased drag inhibiting movement for smaller particle debris. [ABSTRACT FROM AUTHOR]

The non-equilibrium stationary coherences that form in donor–acceptor systems are investigated to determine their relationship to the efficiency of energy transfer to a neighboring reaction center. It is found that the effects of asymmetry in the dimer are generally detrimental to the transfer of energy. Four types of systems are examined, arising from combinations of localized trapping, delocalized (Forster) trapping, eigenstate dephasing, and site basis dephasing. In the cases of site basis dephasing, the interplay between the energy gap of the excited dimer states and the environment is shown to give rise to a turnover effect in the efficiency under weak dimer coupling conditions. Furthermore, the nature of the coherences and associated flux is interpreted in terms of pathway interference effects. In addition, regardless of the cases considered, the ratio of the real part and the imaginary part of the coherences in the energy-eigenbasis tends to a constant value in the steady state limit. [ABSTRACT FROM AUTHOR]

Terahertz (THz) waves, as far-infrared light, offer new opportunities for the optical trapping and manipulation of single cells, in contrast to the other light sources. We present an efficient scheme to flexibly control multiple THz field distribution patterns generated by the laser–plasma interaction in a magnetized plasma. An analytical THz radiation field and two-dimensional particle-in-cell simulation are constructed to verify the feasibility of the scheme. Modulation of the THz gradient force and the energy flux by an asymmetrical THz field is investigated for the purpose of trapping and manipulating particles and cells. In particular, the stabilities of flexibly controlled THz radiation are investigated carefully in the form of the strong and short laser and super-strong magnetic field induced significant spatial structure instabilities and frequency instabilities of terahertz radiation. [ABSTRACT FROM AUTHOR]

Enhanced sampling methods, such as forward flux sampling (FFS), have great capacity for accelerating stochastic simulations of nonequilibrium biochemical systems involving rare events. However, the description of the tradeoffs between simulation efficiency and error in FFS remains incomplete. We present a novel and mathematically rigorous analysis of the errors in FFS that, for the first time, covers the contribution of every phase of the simulation. We derive a closed form expression for the optimally efficient count of samples to take in each FFS phase in terms of a fixed constraint on sampling error. We introduce a new method, forward flux pilot sampling (FFPilot), that is designed to take full advantage of our optimizing equation without prior information or assumptions about the phase weights and costs along the transition path. In simulations of both single and multidimensional gene regulatory networks, FFPilot is able to completely control sampling error. We then discuss how memory effects can introduce additional error when relaxation along the transition path is slow. This extra error can be traced to correlations between the FFS phases and can be controlled by monitoring the covariance between them. Finally, we show that, in sets of simulations with matched error, FFPilot is on the order of tens-to-hundreds of times faster than direct sampling and noticeably more efficient than previous FFS methods. [ABSTRACT FROM AUTHOR]

Reactive molecular dynamics (MD) simulations, especially those employing acceleration techniques, can provide useful insights on the mechanism underlying the transformation of buried organic matter, yet, so far, it remains extremely difficult to predict the time scales associated with these processes at moderate temperatures (i.e., when such time scales are considerably larger than those accessible to MD). We propose here an accelerated method based on flux sampling and kinetic integration along a 1D order parameter that can considerably extend the accessible time scales. We demonstrate the utility of this technique in an application to the dehydration of crystalline cellulose at temperatures ranging from 1900 K to 1500 K. The full decomposition is obtained at all temperatures apart from T = 1500 K, showing the same distribution of the main volatiles (H2O, CO, and CO2) as recently obtained using replica exchange molecular dynamics. The kinetics of the process is well fitted with an Arrhenius law with Ea = 93 kcal/mol and k0 = 9 × 1019 s−1, which are somehow larger than experimental reports. Unexpectedly, the process seems to considerably slow down at lower temperatures, severely departing from the Arrhenius regime, probably because of an inadequate choice of the order parameter. Nevertheless, we show that the proposed method allows considerable time sampling at low temperatures compared to conventional MD. [ABSTRACT FROM AUTHOR]

Graphene films were exposed to low-pressure capacitively coupled (E-mode) and inductively coupled (H-mode) argon radio frequency plasmas to investigate damage formation by very-low-energy ion irradiation. In the H-mode, plasma parameters were assessed by a Langmuir probe and plasma sampling mass spectrometry to determine the conditions of fixed ion fluence but with different average ion energies. The populations of argon metastable and resonant argon atoms were also measured by optical absorption spectroscopy to determine their contribution to the total energy flux during plasma treatment. In the H-mode, in which plasma-graphene interactions are dominated by ion irradiation effects, Raman spectroscopy reveals a significant rise in the D/G ratio and full width at half maximum of the G peak as well as the onset of graphene amorphization, even at very low ion energies (between 7 and 13 eV). In the E-mode characterized by comparable ion energy but much lower ion density, significant damage is also observed, a feature ascribed to the additional energy flux linked to the de-excitation of metastable argon species on the graphene surface. [ABSTRACT FROM AUTHOR]

The atmospheric kinetic energy spectrum and energy cascade are investigated in idealized simulations of radiative–convective equilibrium (RCE). WRF is employed to perform cloud-resolving simulations of an idealized radiative–convective equilibrium with and without aggregation with Δx = 4 km. The horizontal kinetic energy (HKE) spectrum for the aggregated simulation in the upper troposphere is steeper than the nonaggregated case and closer to −5/3. The HKE spectra for the nonaggregated simulation in the upper troposphere and the lower stratosphere are much shallower than the −5/3 spectrum. In the upper troposphere, the divergent kinetic energy has a similar magnitude to the rotational kinetic energy in both the nonaggregated simulation and aggregated simulation. Energy is mainly gained from the buoyancy flux and mainly lost from the vertical energy flux for scales larger than 20 km. Downscale energy transfer is found in the upper troposphere. Numerical dissipation is the main source of energy loss at small scales. In the lower stratosphere, the divergent kinetic energy dominates the kinetic energy spectrum in both simulations. Energy is mainly gained from the vertical energy flux and is balanced by the loss from the buoyancy flux term, transfer term, and dissipation. An Eliassen–Palm flux analysis suggests that wave–mean-flow interaction may be responsible for the upscale energy transfer found in the lower stratosphere. The magnitudes of our kinetic energy spectra are similar to spectra calculated from aircraft data. Rotation is found to promote aggregation and steepen the energy spectrum. [ABSTRACT FROM AUTHOR]

Surface waves propagating along the planar interface between an exponentially graded-index medium and the non-Kerr-type nonlinear medium are described analytically. Equations describing the stationary transverse electric wave propagation containing two-component spatially and intensity dependent dielectric function are formulated. The proposed model describes an appearance at the finite distances from the interface a self-focusing nonlinear response when the electric field amplitude exceeds the critical value. New features of the localization of surface wave depending on the optical and geometric parameters of the system are specified analytically. An increase in the frequency adduces to an increase in the field penetration depth in the nonlinear medium and to a reducing the penetration depth in the exponentially graded-index medium. The thickness of the formed near-surface layer with a nonlinear response is about two light localization lengths along the interface. This thickness reduces with an increase in the system parameter. Its maximum at the critical value of the effective refractive index is observed and explicit equation determining this maximum is obtained. Explicit equation of the time-average total power flow conserving along the medium interface is calculated. The main part of the energy flux of the surface wave is concentrated in the near-surface layer in a wide range of values of the system parameters. [ABSTRACT FROM AUTHOR]

Scalar polarization modes of gravitational waves, which are often introduced in the context of the viable extension of gravity, have been actively searched for. However, couplings of the scalar modes to matter are strongly constrained by fifth-force experiments. Thus, the amplitude of scalar polarization in the observed gravitational-wave signal must be significantly suppressed compared to that of the tensor modes. Here, we discuss the implications of the experiments in the solar system on the detectability of scalar modes in gravitational waves from compact binary coalescences, taking into account the whole processes from the generation to the observation of gravitational waves. We first claim that the energy carried by the scalar modes at the generation is, at most, that of the tensor modes from the observed phase evolution of the inspiral gravitational waves. Next, we formulate general gravitational-wave propagation and point out that the energy flux hardly changes through propagation as long as the background changes slowly compared to the wavelength of the propagating waves. Finally, we show that the possible magnitude of scalar polarization modes detected by ground-based gravitational-wave telescopes is already severely constrained by the existing gravity tests in the solar system. [ABSTRACT FROM AUTHOR]

Seismic‐acoustic wavefield propagations on synthetic 2D models formed by different structural backgrounds are analysed in four test cases. These test cases were carried out employing staggered‐grid finite differences and absorbing boundaries of the convolutional perfectly matched layers type, which allowed analysing in a time of 7.0 s: (a) the seismic‐acoustic wavefield behaviour, (b) the kinetic seismic energy flux and potential seismic energy flux and (c) the energy differences (ΔKEF/ΔPEF) due to each type of proposed structure. In the first two test cases, a relationship was observed between average kinetic seismic energy flux/potential seismic energy flux values and the different structural densities ε of each synthetic model, which were formed by a similar type of structure (fractures). The average kinetic seismic energy flux values increased when ε decreased, whereas the average potential seismic energy flux values decreased when ε also decreased. The largest ΔKEF/ΔPEF values were observed for those models with more structures, reaching up to 0.2 × 108/0.21 × 108 J/m2 in the first test case and up to 1.95 × 108/1.91 × 108 J/m2 in the second test case. Meanwhile, for those models with less number of structures was 0.04 × 108/0 J/m2 in test case 1 and 0.26 × 108/0.61 × 108 J/m2 in test case 2. In the third test case, a relationship was observed between the average potential seismic energy flux values and the ε values, but not with the average kinetic seismic energy flux values, the synthetic models of which were formed by different types of structures (lobes and fractures under different shapes and sizes). The kinetic seismic energy fluxes were more affected by structures closer to each other than by those further apart. Meanwhile, the potential seismic energy fluxes were more affected by larger structures, maintaining a relationship with the seismic frequency and wavelength. The largest ΔKEF/ΔPEF values reached up to 3.42 × 108/3.24 × 108 J/m2 in model with the highest ε value, whereas up to 0.49 × 108/0.67 × 108 J/m2 in the model with the lowest ε value. In the fourth test case, similar types of structures (fractures) were analysed under different orientations in each model. The kinetic seismic energy fluxes/potential seismic energy fluxes were higher in the model formed by better‐oriented structures or parallel with respect to the propagation direction of the seismic‐acoustic wavefield. These energy differences between each test case show how not only the number of structures in a model and the ε values influenced the seismic‐acoustic wavefield and the kinetic seismic energy flux/potential seismic energy flux, but also the structural aspects, the intrinsic elastic properties (e.g. the density used in structures), location (separation between structures) and orientation of structures. [ABSTRACT FROM AUTHOR]

We investigate the role of the laminar/turbulent interface in the interscale energy transfer in a boundary layer undergoing bypass transition with the aid of the Kármán–Howarth–Monin–Hill (KHMH) equation. A local binary indicator function is used to detect the interface and employed subsequently to define two-point intermittencies. These are used to decompose the standard-averaged interscale and interspace energy fluxes into conditionally averaged components. We find that the inverse cascade in the streamwise direction reported in an earlier work arises due to events across the downstream or upstream interfaces of a turbulent spot. However, the three-dimensional energy flux maps reveal significant differences between these two regions: in the downstream interface, inverse cascade is stronger and dominant over a larger range of streamwise and spanwise separations. We explain this finding by considering a propagating spot of simplified shape as it crosses a fixed streamwise location. We derive also the conditionally averaged KHMH equation, thus generalising similar equations for single-point statistics to two-point statistics. We compare the three-dimensional maps of the conditionally averaged production and total energy flux within turbulent spots against the maps of standard-averaged quantities within the fully turbulent region. The results indicate remarkable dynamical similarities between turbulent spots and the fully turbulent region for two-point statistics. This has been known only for single-point quantities, and we demonstrate here that the similarity extends to two-point quantities as well. [ABSTRACT FROM AUTHOR]

Taking the realms of business, finance and economic history by storm, polycrisis captures the complexity of an increasingly uncertain world in a state of flux and transition. Proponents of the polycrisis model, such as prominent economic historian and Financial Times contributing editor Adam Tooze, propose polycrisis as a marker of our age, capturing overlapping and interconnected crises beyond cause and effect. In his article, the authors offer some prompts for considering the usefulness and limitations of polycrisis for the anthropological toolkit. The authors cautiously welcome the polycrisis trope as a multidimensional means to account for the consequences of interrelated crises in an unprecedented era. [ABSTRACT FROM AUTHOR]

The Benguela Niño/Niña events manifest the anomalous signals of sea surface temperature (SST) in the coastal region of the tropical Atlantic Ocean. These events are triggered by the interannual modulation of either equatorial waves or local atmospheric forcing. In the present study, the mechanism that equatorial waves induce the coastal SST anomaly is investigated in terms of the transfer episodes of wave energy. The analysis suggests that most of the coastal events can be reproduced by subseasonal wind forcing with an interannual modulation that excites oceanic waves of the first three baroclinic modes. The transfer routes of wave energy illustrate the role of wave dynamics that explains how the interannual variability of SST in the equatorial Atlantic is connected with that in coastal regions. The linearly superposed sign‐indefinite potential energy flux owing to waves manifests its capability of sufficiently displacing the thermocline so as to trigger the coastal events. The results suggest that the equatorial wave signal is able to provide credible predictions for remotely forced Benguela Niño/Niña events if a proper transection in central equatorial Atlantic with an appropriate threshold is selected for observing. Plain Language Summary: Extreme climate events in the nearshore region along the southwest coast of Africa, as known as Benguela Niño/Niña with anomalous sea temperature, current, and precipitations, are found to be associated with a climate system in the equatorial Atlantic. In particular, ocean waves from the equatorial region are believed to propagate along the coastline and cause the extreme climate in the nearshore region. However, the triggering of the Benguela Niño/Niña is still unclear. The change in local winds, air temperature, and precipitations can easily break the connection of the waveguide between the equatorial and the coastal region. This study applied a simple model successfully using wave dynamics to reproducing those coastal events. By applying a recently developed scheme for investigating the transfer of wave energy, we have revealed how the Benguela Niño/Niña is triggered during the wave propagation. The results suggest the equatorial wave signal as a potential index to forecast the Benguela Niño/Niña. Key Points: The interannual anomaly of observed coastal sea surface temperature (SST) is reproduced by exciting equatorial waves of the gravest three baroclinic modesWave energy transfer route is revealed to connect the equatorial Atlantic with the coastal Angola and Benguela regionsSuperposed potential energy transport by equatorial waves in multiple baroclinic modes triggers the coastal SST events [ABSTRACT FROM AUTHOR]

In this article, we analyze the impact of the off-axis noncanonical vortex on the dynamics of 3D energy flux. The results reveal that the properties of energy flux are significantly influenced by the anisotropy parameter σ c of the off-axis noncanonical vortex. It is demonstrated that by adjusting the anisotropy parameter, we can control the transverse energy flux, from the position of the transverse energy tornado and the distribution of the transverse energy strength to the rotation direction of the transverse energy flux as the beam propagates. The interesting phenomenon, the reversed energy flux, is also closely related to the anisotropy parameter. The position and size of the reversed energy flux region, as well as the production of two energy tornadoes with opposite rotating directions, resembling a Chinese "Taiji" pattern, can be controlled by varying the anisotropy parameter. This result will potentially provide a new freedom for tailoring the 3D optical field and be useful in optical manipulation and processing. [ABSTRACT FROM AUTHOR]

The probability flux and velocity in stochastic reaction networks can help in characterizing dynamic changes in probability landscapes of these networks. Here, we study the behavior of three different models of probability flux, namely, the discrete flux model, the Fokker-Planck model, and a new continuum model of the Liouville flux. We compare these fluxes that are formulated based on, respectively, the chemical master equation, the stochastic differential equation, and the ordinary differential equation. We examine similarities and differences among these models at the nonequilibrium steady state for the toggle switch network under different binding and unbinding conditions. Our results show that at a strong stochastic condition of weak promoter binding, continuum models of Fokker-Planck and Liouville fluxes deviate significantly from the discrete flux model. Furthermore, we report the discovery of stochastic oscillation in the toggle-switch system occurring at weak binding conditions, a phenomenon captured only by the discrete flux model. [ABSTRACT FROM AUTHOR]

For inertial reaction dynamics, a transition state theory rate constant obtained from an inaccurate reaction coordinate can be a posteriori corrected with reactive flux methods. In contrast, reaction coordinate errors in overdamped mean first passage time calculations cannot be a posteriori corrected. This work develops an overdamped version of the transmission coefficient. The calculation requires information from committor analyses and an estimate of the diffusivity along the committor coordinate. We illustrate the calculation for a simple two-dimensional potential that admits exact solutions. [ABSTRACT FROM AUTHOR]

Recently, a "mode-hopping" phenomenon has been observed in a NF-κB gene regulatory network with oscillatory tumor necrosis factor (TNF) inputs. It was suggested that noise facilitates the switch between different oscillation modes. However, the underlying mechanism of this noise-induced "cellular mode-hopping" behavior remains elusive. We employed a landscape and flux approach to study the stochastic dynamics and global stability of the NF-κB regulatory system. We used a truncated moment equation approach to calculate the probability distribution and potential landscape for gene regulatory systems. The potential landscape of the NF-κB system exhibits a "double ring valley" shape. Barrier heights from landscape topography provide quantitative measures of the global stability and transition feasibility of the double oscillation system. We found that the landscape and flux jointly govern the dynamical "mode-hopping" behavior of the NF-κB regulatory system. The landscape attracts the system into a "double ring valley," and the flux drives the system to move cyclically. As the external noise increases, relevant barrier heights decrease, and the flux increases. As the amplitude of the TNF input increases, the flux contribution, from the total driving force, increases and the system behavior changes from one to two cycles and ultimately to chaotic dynamics. Therefore, the probabilistic flux may provide an origin of chaotic behavior. We found that the height of the peak of the power spectrum of autocorrelation functions and phase coherence is correlated with barrier heights of the landscape and provides quantitative measures of global stability of the system under intrinsic fluctuations. [ABSTRACT FROM AUTHOR]

Increasing extreme ultraviolet (EUV) photon power in laser-produced plasma (LPP) sources is critically important for efficient future nanolithography devices. Enhancing the lifetime of the optical collector system in these devices is another important challenge for reliable and economically feasible devices. In this work, various mechanisms affecting ion acceleration in LPP were investigated to predict the maximum ion energies and flux arriving at the collecting mirror surfaces. Plasma evolution produced by an Nd:YAG laser from Sn targets was studied in detail to predict the dynamics of EUV producing ions and their contribution to the EUV power. The multiphysics fully 3D integrated HEIGHTS computer package was used in this analysis. HEIGHTS simulations of detail plasma evolution and ion kinetic energies were compared with various worldwide experimental data. Excellent agreement was shown regarding the range of ion kinetic energies and their angular distribution as well as recombination processes and their effect on the temporal output of EUV photons. Spatial and charge distributions were predicted for EUV producing ions and ionic debris. The analysis showed that mainly two Sn ions, i.e., Sn XII and Sn XIII, determine the EUV source intensity and spatial location. It was also shown that reducing the laser spot size and increasing the pulse duration allow a significant reduction in ion kinetic energies that is important for a longer lifetime of the optical collection system. [ABSTRACT FROM AUTHOR]

A combined electronic-nuclear wave packet motion is accompanied by temporal changes of probability flux densities. Using a two dimensional model, we study such densities in the vicinity of a conical intersection (CI) between the potential energy surfaces of two electronically excited states. When the dynamics is accompanied by an efficient population transfer, the electronic flux density behaves nearly time-independent although the nuclear flux does not. The second case involves a nuclear motion where the CI is surrounded. There, the nuclear wave packet undergoes a bifurcation, and the electronic density shows characteristics of a rotation. The electronic flux, however, exhibits a constant directional dynamics during the nuclear motion. The geometrical phase which appears in comparing the nuclear dynamics derived from the coupled motion and the Born-Oppenheimer calculation is also seen in the nuclear flux dynamics. [ABSTRACT FROM AUTHOR]

This paper presents a perspective on flux pumps. Flux pumps are a means of providing current to a coil or a magnet without direct electrical or physical contact. Typically, a coil would be charged directly using current leads, which would then be withdrawn if the magnets operated in the persistent mode (as with magnetic resonance imaging) or left in place if the field required maintenance or ramping. Flux pumps use the principle of magnetic induction. They present two distinct advantages. The first is that there is no direct connection to the external world and, therefore, no associated heat loss. The second is that, although high current can be developed in the magnet or the coil, these can be produced without the need for high-current power supplies, which are bulky and expensive. Flux pumps are especially appropriate for machines constructed from high temperature superconductors (HTSs). They facilitate the full use of the HTS's current carrying capability, cheaply and simply, enabling smaller, lighter, and more powerful magnets, motors, and generators. [ABSTRACT FROM AUTHOR]

We study steady-state flux of particles diffusing on a flat surface and trapped by absorbing spikes of arbitrary length periodically protruding from a reflecting base. It is assumed that the particle concentration, far from this comblike boundary, is kept constant. To find the flux, we use a boundary regularization approach that replaces the initial highly rough and heterogeneous boundary by an effective boundary which is smooth and uniform. After such a replacement, the two-dimensional diffusion problem becomes essentially one-dimensional, and the steady-state flux can be readily found. Our main results are simple analytical expressions determining the position of the smooth effective boundary and its uniform trapping rate as functions of the spike length and interspike distance. It is shown that the steady-state flux to the effective boundary is identical to its counterpart to the initial boundary at large distances from this boundary. Our analytical results are corroborated by Brownian dynamics simulations. [ABSTRACT FROM AUTHOR]

A three-dimensional (3D) general coupling model for electromigration has been developed with the use of the mass conservation equation. The flux terms that include concentration gradient, electron wind force, stress migration, and thermal migration are considered. The constitutive equation for the electromigration strain has been derived. Then, the governing equations for one-dimensional (1D) metal lines are obtained for both totally fixed and stress-free mechanical boundary conditions. The numerical results reveal that the hydrostatic stress is significantly lower than the predicted results in the existing literature for the totally fixed configuration. Extensive discussions are presented to provide the explanations of such difference. The vacancy concentration gradient plays an important role in formulating electromigration problems. The current-driven flux can be entirely balanced by the concentration gradient that acts as an opposing force during electromigration under a stress-free condition in steady-state. The new solutions of the critical threshold jL, the product of current density, and metal line length are obtained in terms of vacancy concentration. As electromigration is eventually determined by the void growth, the critical vacancy concentration is used to reanalyze Blech's experiment data. The theoretical predictions are consistent with the experimental observations. [ABSTRACT FROM AUTHOR]

Passive thermal probes were applied on two different plasma spraying devices to gain a detailed understanding of the energy flux towards the substrate under atmospheric pressure. The challenge of very high thermal load was solved by using an advanced time-resolved measuring and evaluation technique. The combination with a controlled movement of the jets allowed to obtain insightful radial profiles. The energy flux to the substrate changes linearly to the electrical input power. When adding diatomic gases (H2/N2) to the gas mixture the energy flux increases significantly, suggesting a more efficient energy transport. For increasing the axial distance, the energy flux shows a quadratic reduction. The obtained radial profiles are exemplarily utilized to show the inhomogeneous effect of powder injection on the energy flux distribution. [ABSTRACT FROM AUTHOR]

Submesoscale currents, comprising fronts and mixed-layer eddies, exhibit a dual cascade of kinetic energy: a forward cascade to dissipation scales at fronts and an inverse cascade from mixed-layer eddies to mesoscale eddies. Within a coarse-graining framework using both spatial and temporal filters, we show that this dual cascade can be captured in simple mathematical form obtained by writing the cross-scale energy flux in the local principal strain coordinate system, wherein the flux reduces to the sum of two terms, one proportional to the convergence and the other proportional to the strain. The strain term is found to cause the inverse energy flux to larger scales while an approximate equipartition of the convergent and strain terms captures the forward energy flux, demonstrated through model-based analysis and asymptotic theory. A consequence of this equipartition is that the frontal forward energy flux is simply proportional to the frontal convergence. In a recent study, it was shown that the Lagrangian rate of change of quantities like the divergence, vorticity, and horizontal buoyancy gradient are proportional to convergence at fronts, implying that horizontal convergence drives frontogenesis. We show that these two results imply that the primary mechanism for the forward energy flux at fronts is frontogenesis. We also analyze the energy flux through a Helmholtz decomposition and show that the rotational components are primarily responsible for the inverse cascade while a mix of the divergent and rotational components cause the forward cascade, consistent with our asymptotic analysis based on the principal strain framework. [ABSTRACT FROM AUTHOR]

We suggest rethinking ecology as a set of continuous, interconnected dynamics and spatial networks that would represent an alternative framework to the traditional organizational levels--cell, organism, population, community, and ecosystem. We draw on unifying biological theories--information theory, cell theory, and metabolic theories--to propose a continuous space for living systems that avoids epistemological constraints imposed by a priori assumptions of discrete levels of biological organization. The discrete levels of organization that ecologists have traditionally envisioned can be viewed instead as coarse-grained, localized groupings within continuous dimensions of information (I), cell number (C), and energy flux (E). Moving from levels of organization to emergent properties of information, cells, and energy flux allows us to illustrate how diverse ecological and evolutionary phenomena--such as allometric and diversity-related scaling patterns, predator-prey dynamics, evolutionary trajectories, and alternative stable states--can be represented within the same continuum. We suggest that there may be structure within this information-cells-energetic flux (ICE) framework that unifies ecology from the beginning of life to the present and provides a useful lens through which patterns and processes in nature can be viewed. [ABSTRACT FROM AUTHOR]

Dynamic membrane (DM) technology was applied for treatment of synthetic dairy wastewater. The study consisted of two step. In first step of the study, changes in DM formation time and solid removal efficiency were investigated at different operational conditions using support materials having different pore sizes (20 and 40 µm) in an external filtration unit being situated at the outlet of up flow sludge blanket reactor. During the operation, three runs were done for each studied pore sizes and physical cleaning was done two times for each pore sizes. DM formation time became shorter as the pore sizes of support layer decreased for the initial stages of the support layer usage. On the other hand, after DM formation, support layer lost its original properties and its filtration characteristics became independent of pore size. Solid removal at different pore sizes was followed with turbidity measurements. The turbidity removal efficiency was more than 92 % for all pore sizes. The initial flux was 97 and 95 L/m2h for 20 and 40 µm pore size, respectively. The flux after DM formation during operation with 20 µm pore size was slightly higher than 40 µm pore size. The cake layer resistance effect on total membrane resistance was evaluated for 40 µm pore size. It was calculated for run-3 as 2.34x 109 1/m corresponding 99.5 % of total resistance. According to these results, cake layer resistance composed most of the total resistance. Among the pore sizes tried, 20 µm was found to be optimum pore size considering DM formation time, flux, trans membrane pressure and treatment performance. [ABSTRACT FROM AUTHOR]

Quantifying regional water and energy fluxes much more accurately from observations is essential for improving climate and earth system models, and their ability to simulate future change. This study uses satellite observations to produce monthly flux estimates for each component of the terrestrial water and energy budget over selected large river basins from 2002 to 2013. Prior to optimisation the water budget residuals vary between 1.5 % and 35 % of precipitation by basin, and the imbalance between the net radiation and the corresponding turbulent heat fluxes ranges between ± 10 Wm−2 in the long term average. In order to further assess these imbalances, a flux-inferred surface storage (FIS) is used for both water and energy, based on integrating the flux observations. This exposes mismatches in seasonal water storage as well as important interannual variability. Our optimisation ensures the flux estimates are consistent with total water storage changes from GRACE on short (monthly) and longer timescales, while also balancing a coupled long term energy budget, by using a sequential approach. All the flux adjustments made during the optimisation are small and within uncertainty estimates using a χ2 test, and interannual variability from observations is retained. The optimisation also reduces formal uncertainties on individual flux components. When compared with results from previous literature in basins such as the Mississippi, Congo and Huang He River, the FIS metrics show the better agreement with GRACE variability and trends in each case [ABSTRACT FROM AUTHOR]

The evolution of the atmospheric temperature in the past, resulted from the EPICA project (European Project for Ice Coring in Antarctica) for the analysis of air bubbles in ice deposits near three weather stations in Antarctica, includes several glacial cycles. According to these studies, the glacial cycle consists of a slow cooling of the Earth's surface at a rate of about 10 − 4 ∘ C per year for almost the entire time of a single cycle (about 100 thousand years) and of a fast process of heating the planet, similar to a thermal explosion. The observed cooling of the planet follows from the imbalance of energy fluxes absorbed by the Earth and going into its surrounding space, and this imbalance is four orders of magnitude less than the accuracy of determination of the fluxes themselves. The inconsistency of the popular Milankovich theory is shown, according to which glacial cycles in the evolution of the Earth's thermal state are associated with changes in the Earth's orbit relative to the Sun. In considering the glacial cycle as the transition between the warm (contemporary) and cold thermal states of the Earth with a difference in their temperatures of 12 ∘ C according to measurements, we construct the energetic balance for each of Earth's states. The fast transition between the Earth's cold and warm states results from the change of the Earth's albedo due to the different volcano activity in these states. There is the feedback between the aggregate state of water covering the Earth's surface and volcanic eruptions, which become intense when ice covers approximately 40 % of the Earth's surface. Dust measurements in ice deposits within the framework of the EPICA project confirms roughly a heightened volcano eruption during the cold phase of the glacial cycle. Numerical parameters of processes related to the glacial cycle are analyzed. [ABSTRACT FROM AUTHOR]

In this work, we use molecular dynamics simulations with a polarizable force field, namely, the modified AH/BK3 model [J. Kolafa, J. Chem. Phys. 145, 204509 (2016)], in combination with the forward flux sampling technique, to calculate the rates of homogeneous nucleation of NaCl from supersaturated aqueous solutions at 298 K and 1 bar. A non-polarizable model that reproduces the experimental equilibrium solubility {AH/TIP4P-2005 of Benavides et al. [J. Chem. Phys. 147, 104501 (2017)]} is also used for comparison. Nucleation rates calculated from the polarizable force field are found to be in good agreement with experimental measurements, while the non-polarizable model severely underestimates the nucleation rates. These results, in combination with our earlier study of a different non-polarizable force field [H. Jiang et al., J. Chem. Phys. 148, 044505 (2018)], lead to the conclusion that nucleation rates are sensitive to the details of force fields, and a good representation of nucleation rates may not be feasible using available non-polarizable force fields, even if these reproduce the equilibrium salt solubility. Inclusion of polarization could be important for an accurate prediction of nucleation rates in salt solutions. [ABSTRACT FROM AUTHOR]

A gas aggregation source based on DC magnetron sputtering was investigated using a passive thermal probe and supplementary diagnostics (Langmuir probe and quartz crystal microbalance). Parameter variations of pressure, axial distance, and magnetron current have been performed for three different targets (pure Cu, pure W, composite Cu/W) in argon discharge. The measurements showed the energy flux to be significantly higher for the case of the pure tungsten and the composite target compared to the copper target, which is likely a result of the strongly increased amount of neutrals being reflected from the heavier targets. Furthermore, gas rarefaction by the sputtered atoms was found to be essential for the understanding of the observed energy flux and that the dominant contributors to the energy flux in the higher pressure regime are comparable to those observed in the conventional lower pressure regime. Selected deposited films have been investigated ex-situ by scanning electron microscopy, which allowed us to gain insight into the nanoparticle formation in relation to the observed energy conversion. [ABSTRACT FROM AUTHOR]

The energy flux to a surface during plasma exposure and the associated surface heating are of long standing interest as they contribute to the physico-chemical changes that occur during plasma-based materials synthesis and processing. Indeed, the energy delivered to the surface, via a flux of particles and photons, in concert with a flux of reactive species serves to chemically modify, etch, and/or deposit materials, with an efficacy that depends on the plasma processing environment. A unique feature of plasma synthesis and processing is that most of the delivered energy is absorbed at or very near the surface over short (picosecond) time scales. The dissipation of thermal energy proceeds through electron-electron and/or electron-phonon interactions as they propagate through the material, with relaxation time scales that can be orders of magnitude slower. Typically then, the surface is not in thermal equilibrium with the bulk material. Fast, surface-sensitive techniques are thus required to fully appreciate the dynamics of the plasma-surface interaction. In this work, we employ pump-probe Time-Domain Thermoreflectance, a surface sensitive technique typically used to measure thermal properties of thin films, to determine electron heating of thin metal films during exposure to an atmospheric pressure plasma jet. The results, in conjunction with current measurements, are used to develop a first order understanding of plasma jet-surface interactions. The results show that the energy delivered by the plasma jet causes a localized increase in electron energy within the thin film over an area commensurate with the plasma jet radius. [ABSTRACT FROM AUTHOR]

Similarity laws (SLs) are useful for correlation and prediction of plasma parameters at different scales, which have been verified for geometrically symmetric capacitive radio-frequency (rf) discharges in nonlocal kinetic regimes. In this work, we demonstrate the applicability of SLs to dual-frequency rf discharges and confirm that similarity relations still hold considering the electrical asymmetry effect (EAE). By simultaneously tuning the control parameters (the gas pressure p, discharge gap d, and driving frequency f), we examine the similarity relations in rf plasmas via fully kinetic particle-in-cell simulations with the external circuits coupled and solved self-consistently. The validity of the SL scalings in dual-frequency rf plasmas with the EAE is confirmed for parameters such as the electron/ion density, ion flux, dc self-bias, ion energy distribution function, and power absorption. Although adjusted by the EAE, the dc self-bias and ion energy distribution functions are identified as similarity invariants under similar discharge conditions. Furthermore, the plasma series resonance phenomenon, filamentation of power depositions of electrons and ions in bulk plasma, and electric field reversal are observed in dual-frequency discharges with the EAE, which can also be exactly replicated under similar discharge conditions. The results further extend the application of SL scaling to dual-frequency rf plasmas, providing a more comprehensive understanding of the scaling characteristics in rf plasmas. [ABSTRACT FROM AUTHOR]