bluuebunny/crossref_metadata_2025_split huggingface dataset:
Redox potentials in ionic liquids: Anomalous behavior?
Authors: Renfro Chloe A. , Hymel John H. , McDaniel Jesse G. 
Published: May 2024

Redox potentials depend on the nature of the solvent/electrolyte through the solvation energies of the ionic solute species. For concentrated electrolytes, ion solvation may deviate significantly from the Born model predictions due to ion pairing and correlation effects. Recently, Ghorai and Matyushov [J. Phys. Chem. B 124, 3754–3769 (2020)] predicted, on the basis of linear response theory, an anomalous trend in the solvation energies of room temperature ionic liquids, with deviations of hundreds of kJ/mol from the Born model for certain size solutes/ions. In this work, we computationally evaluate ionic solvation energies in the prototypical ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate (BMIM/BF4), to further explore this behavior and benchmark several of the approximations utilized in the solvation energy predictions. For comparison, we additionally compute solvation energies within acetonitrile and molten NaCl salt to illustrate the limiting behavior of purely dipolar and ionic solvents. We find that the overscreening effect, which results from the inherent charge oscillations of the ionic liquid, is substantially reduced in magnitude due to screening from the dipoles of the molecular ions. Therefore, for the molten NaCl salt, for which the ions do not have permanent dipoles, modulation of ionic solvation energies from the overscreening effect is most significant. The conclusion is that ionic liquids do indeed exhibit unique solvation behavior due to peak(s) in the electrical susceptibility caused by the ion shell structure; redox potential shifts for BMIM/BF4 are of more modest order ∼0.1 V, but may be larger for other ionic liquids that approach molten salt behavior.
The transformation of the rotational energy of a Kerr black hole
Authors: Zhang Shu-Rui , Prakapenia Mikalai 
Published: May 2024

Abstract
This paper analyzes the feedback of the rotational energy extraction from a Kerr black hole (BH) by the ‘ballistic method’, i.e. the test particle decay in the BH ergosphere pioneered by Roger Penrose. The focus is on the negative energy counterrotating particles (which can be massive or massless) going in towards the horizon, and the feedback on the BH irreducible mass is assessed. Generally, the change in irreducible mass is a function of the conserved quantities of the particle. For an extreme Kerr BH and in the limit

μ
1

/

M
→
0

, all the reduced transformable energy goes into the irreducible mass (i.e.

Δ

M
irr

/

|

E
1

|

→
∞

), resulting in high irreversibility. The amount of extracted energy from the BH using test particles is much lower than the change of transformable energy. For non-extreme Kerr BHs, the effective potential of particle motion on the equatorial plane in Kerr spacetime is analyzed, and it is demonstrated that the Penrose process can only be undergone by BHs with a dimensionless spin

a
^

>
1

/

2

if the decay point coincides with the turning point. Based on that, the lower limit of the change in irreducible mass is provided as a function of the dimensionless spin of the BH. The significance of the increase in the irreducible mass of the BH during the energy extraction process is generally and concisely illustrated by introducing the concept of transformable energy of the BH. The feedback from the Penrose process on the irreducible mass demonstrates the irreversibility of energy extraction and highlights that the total amount of energy that can be extracted from a BH is less than previously anticipated.
Giant enhancement of coercivity in β-Ni(OH)2 decorated Ti3C2T
x
MXene nanosheets
Authors: Debnath Anup , Bera Sumanta , Mahapatra Gouranga , Kapuria Arijit , Saha Shyamal K 
Published: May 2024

Abstract
Ti3C2T
x
MXenes are of great interest due to their high conductivity, easy synthesis and unique functional properties. Functionalisation and structural engineering are essential for various applications because of their dramatic influences on different chemical and physical properties. Therefore, understanding the mechanism of the etching reaction of Ti3C2T
x
from its parent MAX phase is crucial. The structural details also need to be understood for application in different practical devices. In this study, 2D Ti3C2T
x
sheets with an average thickness of 3.48 nm and lateral dimension of 5.5 µm were synthesised by removing Al layers from the Ti3AlC2 MAX phase. The step-by-step etching mechanism was analysed with the help of Rietveld refinement of the powder x-ray diffraction data. The structural details and influence of different functional groups on the surface were also studied using transmission electron microscopy, x-ray photoelectron spectroscopy, and Raman spectroscopy. The magnetic behaviour and magnetic interaction of bare 2D Ti3C2T
x
decorated with β-Ni(OH)2 nanosheets on its surface was studied. For the bare 2D Ti3C2T
x
MXene sheets, a weak ferrimagnetic ordering with negligible coercivity was found. However, the β-Ni(OH)2-decorated Ti3C2T
x
MXene sheets exhibit strong ferrimagnetic ordering with a sufficiently large coercivity of 0.2 T at 2 K and a transition temperature of 246 K. The generation of this interfacial ferrimagnetism is discussed in light of the interfacial charge transfer originating from d-p mixing. These 2D magnets generated at the interface could be useful for application in different spintronic devices.
Synthesizable manganese nitride with giant magnetocrystalline anisotropy energy
Authors: Yang Ze-Jin 
Published: May 2024

Abstract
Using a crystal structure prediction program (CALYPSO), we found many experimentally synthesizable low-energy structures with perfect or nearly perfect easy-axis magnetocrystalline anisotropy energy (MAE) in manganese nitride, including MnN, Mn2N, Mn3N2, Mn5N2, and Mn4N, respectively, which are the stoichiometries more frequently studied by experimental researchers. MnN (

I

4
―

2
d

) shows giant MAE with values of E
001 = 1006, E
010 = 0, and E
100 = 920 μeV/atom (same hereafter in the abstract for the MAE unit). Mn3N2 (P42/mmc) shows perfect easy-axis MAE, whose E
010 = E
100 = 12, whereas Ibam has a nearly perfect easy-axis MAE with values of E
001 = 324 and E
010 = 345. Mn2N has four almost totally perfect easy-axis MAE structures, including P4/mmm (E
001 = 249, E
100 = 250), Pccm (E
001 = E
100 = 62), P4/nmm (E
001 = 58, E
100 = 60), and Imma (E
001 = 108, E
100 = 109). Mn4N has one perfect structure, I4/mmm (E
001 = E
100 = 169), and two nearly perfect structures, including Fmmm (E
001 = 126, E
010 = 121) as well as I4/mmm (E
010 = 127, E
100 = 133). Too many valuable structures deserve to be further studied by both theoretical and experimental scientists regarding their other magnetic properties except for the present MAE. The present study might attract close attention to several of these compounds.
The Xe isotope nuclear resonance frequency shift of NMR angular velocity sensors due to transverse gradient magnetic fields
Authors: Jie Shaofeng , Liu Zhanchao 
Published: May 2024

Abstract
The nuclear magnetic resonance (NMR) angular velocity sensor detects angular velocity by measuring the shift in the nuclear spin precession frequency, which is of fundamental interest. Recent studies have revealed the parameter dependency of nuclei frequency shifts induced by non-uniformly distributed polarized pump beams, temperature, and magnetic field properties. In this study, we investigated the effect of the linear transverse gradient magnetic field on the frequency ratio shift of the Xe isotope nuclear resonance frequency in the NMR sensors. A theoretical analysis method was proposed based on the Fermi contact interaction in atomic polarization and the spin-diffusion relaxation of 129Xe and 131Xe nuclei. The frequency ratio shift of the Xe isotope under different x-axis gradient magnetic fields was measured experimentally. Furthermore, we eliminated the equivalent residual magnetic field through a feedback system and compensated for the original gradient magnetic field in the system, which contributed to accurately revealing the frequency shift induced by the magnetic field gradient. The results indicate that the frequency ratio shift of the Xe isotope is proportional to the strength of the second-order linear transverse gradient magnetic field. This study provides a reference for the analysis and evaluation of the presence of the gradient magnetic field in the NMR angular velocity sensor.
Time-reversibility and nonvanishing Lévy area
Authors: Gottwald Georg A , Melbourne Ian 
Published: May 2024

Abstract
We give a complete description and clarification of the structure of the Lévy area correction to Itô/Stratonovich stochastic integrals arising as limits of time-reversible deterministic dynamical systems. In particular, we show that time-reversibility forces the Lévy area to vanish only in very specific situations that are easily classified. In the absence of such obstructions, we prove that there are no further restrictions on the Lévy area and that it is typically nonvanishing and far from negligible.
Fitting Monte Carlo simulation results with an empirical model of megavoltage x-ray beams for rapid depth dose calculations in water
Authors: O’Brien Allison , Abergel Rebecca J 
Published: May 2024

Abstract

Objective. The purpose of this study was to assess a method of accelerating Monte Carlo simulations for modeling depth dose distributions from megavoltage x-ray beams by fitting them to an empirically-derived function. Approach. Using Geant4, multiple simulations of a typical medical linear accelerator beam in water and in water with an air cavity were conducted with varying numbers of initial electrons. The resulting percent depth dose curves were compared to published data from actual linear accelerator measurements. Two methods were employed to reduce computation time for this modeling process. First, an empirical function derived from measurements at a particular linear accelerator energy, source-to-surface distance, and field size was used to directly fit the simulated data. Second, a linear regression was performed to predict the empirical function’s parameters for simulations with more initial electrons. Main results. Fitting simulated depth dose curves with the empirical function yielded significant improvements in either accuracy or computation time, corresponding to the two methods described. When compared to published measurements, the maximum error for the largest simulation was 5.58%, which was reduced to 2.01% with the best fit of the function. Fitting the empirical function around the air cavity heterogeneity resulted in errors less than 2.5% at the interfaces. The linear regression prediction modestly improved the same simulation with a maximum error of 4.22%, while reducing the required computation time from 66.53 h to 43.75 h. Significance. This study demonstrates the effective use of empirical functions to expedite Monte Carlo simulations for a range of applications from radiation protection to food sterilization. These results are particularly impactful in radiation therapy treatment planning, where time and accuracy are especially valuable. Employing these methods may improve patient outcomes by ensuring that dose delivery more accurately matches the prescription or by shortening the preparation time before treatment in Monte Carlo-based treatment planning systems.
On the influence of electrode surfaces on the plasma chemistry of a capacitive chlorine discharge
Authors: Mahdavipour B , Gudmundsson J T 
Published: May 2024

Abstract
One-dimensional particle-in-cell/Monte Carlo collisional simulations are performed on capacitive chlorine discharges with 2.54 cm gap rf driven by a sinusoidal with voltage amplitude of 222 V at driving frequency of 13.56 MHz. The properties of the discharge, the reaction rates for creation and loss of a few key species, the electron energy probability function, and the primary electron power absorption processes are explored as the gas pressure and the inclusion of secondary electron emission processes in the discharge model is varied. Five cases are investigated, including and neglecting electron, ion, and fast neutrals induced secondary electron emission. The negative ion Cl− is almost entirely created by dissociative attachment and lost through ion-ion recombination, and therefore the capacitive chlorine discharge is recombination dominated.
Tuning critical current density properties of YBa2Cu3O
y
thin films under longitudinal magnetic field by using heavy-ion irradiation
Authors: Sueyoshi Tetsuro , Enokihata Ryusei , Yamaguchi Hiroshi , Semboshi Satoshi , Ozaki Toshinori , Sakane Hitoshi , Nishizaki Terukazu , Ishikawa Norito 
Published: May 2024

Abstract
We attempted to improve the critical current density J
c under a longitudinal magnetic field (LMF) by using columnar defects (CDs) tilted toward the transport current, where the CDs were produced with 80 MeV Xe ions at an incident angle(s) up to φ
i = 87.5° relative to the c-axis of YBa2Cu3O
y
thin films. The formation of CDs extending throughout the film was confirmed by cross-sectional transmission electron microscopy. The CDs tilted at φ
i = 87.5° weakened the magnetic field dependence of J
c under the LMF, providing a J
c higher than that of the unirradiated film in a high magnetic field. This is the first study to demonstrate that CDs and/or irradiation defects contribute to flux pinning under the LMF in high-T
c superconductors. In addition, the J
c under LMF was sensitive to the tilt angle of the CDs: the J
c was reduced by CDs tilted not only at φ
i = 0°, but also at a slightly larger angle relative to the ab-plane, i.e. φ
i = 85°. The introduction of CDs rather disturbs the LMF effect because of the large volume passing through the film thickness, unless the tilt angles of the CDs are within the narrow angular region effective for the LMF effect.
Dissipation in hydrodynamics from micro- to macroscale: wisdom from Boltzmann and stochastic thermodynamics
Authors: Forastiere Danilo , Avanzini Francesco , Esposito Massimiliano 
Published: May 2024

Abstract
We show that macroscopic irreversible thermodynamics for viscous fluids can be derived from exact information-theoretic thermodynamic identities valid at the microscale. Entropy production, in particular, is a measure of the loss of many-particle correlations in the same way in which it measures the loss of system-reservoirs correlations in stochastic thermodynamics (ST). More specifically, we first show that boundary conditions at the macroscopic level define a natural decomposition of the entropy production rate (EPR) in terms of thermodynamic forces multiplying their conjugate currents, as well as a change in suitable nonequilibrium potential that acts as a Lyapunov function in the absence of forces. Moving to the microscale, we identify the exact identities at the origin of these dissipative contributions for isolated Hamiltonian systems. We then show that the molecular chaos hypothesis, which gives rise to the Boltzmann equation at the mesoscale, leads to a positive rate of loss of many-particle correlations, which we identify with the Boltzmann EPR. By generalizing the Boltzmann equation to account for boundaries with nonuniform temperature and nonzero velocity, and resorting to the Chapman–Enskog expansion, we recover the macroscopic theory we started from. Finally, using a linearized Boltzmann equation we derive ST for dilute particles in a weakly out-of-equilibrium fluid and its corresponding macroscopic thermodynamics. Our work unambiguously demonstrates the information-theoretical origin of thermodynamic notions of entropy and dissipation in macroscale irreversible thermodynamics.
The adsorption of CO gas on the surface of boron nitride incorporating 2D carbon allotropes: a DFT analysis
Authors: Ahmed Mohammad Tanvir , Roy Debashis , Roman Abdullah Al , Kowser Zannatul , Islam Shariful , Ahmed Farid 
Published: May 2024

Abstract
The adsorption properties of different Carbon allotropes (i.e., graphene, γ-graphyne, Mobius graphene, and R-graphyne) and their corresponding Boron (N) and Nitrogen (N) incorporated BCN nanostructures toward carbon monoxide (CO) gas are studied via density functional theory calculation. All the adsorbents demonstrated negative formation energies and real frequencies, i.e., can be synthesized and have dynamical stability. The adsorption energies have increased due to B and N incorporation, although still comparatively low for practical application. The highest adsorption energy with suitable recovery time is observed for the Mobius BCN structure, about −0.112 eV and 77.8 ps, respectively. Very nominal charge transfer is observed via Mulliken charge distribution and electrostatic potential map analysis. The changes in energy gap and electrical conductivity are observed due to CO adsorption.
Modelling the transmission behavior of measles disease considering contaminated environment through a fractal-fractional Mittag-Leffler kernel
Authors: Wireko Fredrick A , Adu Isaac K , Gyamfi Kwame A , Asamoah Joshua Kiddy K 
Published: May 2024

Abstract
This work utilises a fractal-fractional operator to examine the dynamics of transmission of measles disease. The existence and uniqueness of the measles model have been thoroughly examined in the context of the fixed point theorem, specifically utilising the Atangana-Baleanu fractal and fractional operators. The model has been demonstrated to possess both Hyers-Ulam stability and Hyers-Ulam Rassias stability. Furthermore, a qualitative analysis of the model was performed, including examination of key parameters such as the fundamental reproduction number, the measles-free and measles-present equilibria, and assessment of global stability. This research has shown that the transmission of measles disease is affected by natural phenomena, as changes in the fractal-fractional order lead to changes in the disease dynamics. Furthermore, environmental contamination has been shown to play a significant role in the transmission of the measles disease.
Modulation instability and extraction of fractional optical solitons in the presence of generalized Kudryashov’s law and dual form of non-local nonlinearity
Authors: Chahlaoui Younes , Umair Muhammad , Butt Asma Rashid , Alshahrani Alanoud A M 
Published: May 2024

Abstract
This research delves into the study of optical solitons governed by Kudryashov’s law of nonlinear refractive index, incorporating a conformable fractional derivative, perturbed terms, and a quadrupled-power law in optical fibers. Employing a novel approach known as the generalized exp(−

S
(
ζ
)

) expansion method, we identify novel optical soliton solutions characterized by exponential, rational, and hyperbolic functions featuring a conformable fractional derivative. These solutions manifest as unified bright-dark, singular, singular periodic, kink, anti-kink, and novel solitary waves. We employ 3D, contour, and 2D plots to analyze the behavior of these solutions across different temporal and fractional-order derivative parameters, offering an understanding of their physical interpretations. Furthermore, we perform modulation instability (MI) analysis that depends on standard linear stability analysis to derive the MI gain spectrum, demonstrating how well our methodology works for nonlinear problems in the natural sciences and engineering domains. This approach provides an effective way to investigate optical solutions in various integer and fractional Schrödinger equations.
Study of deposition temperature effect on spray-deposited copper oxide thin films and its schottky diodes
Authors: Kumar Anuj , Dalal Damini , Singh Amanpal , Kumar Dinesh , Narwal Vinay , Swami Sanjay Kumar , Chaturvedi Neha , Kumar Manoj 
Published: May 2024

Abstract
Due to its ideal optical and electrical properties for upcoming electronic devices, Cu2O is commonly regarded as one of the most promising p-type oxides. Copper (Cu) rapidly deposits mixed phases of its oxides. This article describes the spray deposition method for developing copper oxide thin films at temperatures between 200 and 400 °C on glass substrates coated with ITO. Through optimization of the deposition temperature, Cu2O-rich phases were attained in the copper oxide films, typically around 300 °C. A Cu-rich phase was seen at 200 °C deposition temperature, and this phase progressively diminished at higher temperatures. At 400 °C, the CuO phase began to enrich the films in the meantime. Analysis using an x-ray diffraction (XRD) verified the existence of Cu2O phases (111), (200), and (220). The crystallites were discovered to be between 17.49 and 20.32 nm in size for the films deposited between 300 and 400 °C. The x-ray Photoelectron Spectroscopy (XPS) identifies Cu and oxygen as the main components. Furthermore, it is demonstrated that the deposition temperature significantly affects the copper’s oxidation state. The Atomic Force Microscopy (AFM) investigation showed that as the temperature increased, surface roughness decreased. As the deposition temperature increased, the energy band gap of the deposited films widened from 1.67 to 2.85 eV, as observed by the UV–vis-NIR spectrophotometer. Moreover, the fabrication of Schottky diodes with Cu metal contacts is also reported. These fabricated diodes showed a proportionate rise in barrier height with increasing deposition temperature.
Robust 1-norm Periodograms for Analysis of Noisy Non-Gaussian Time Series with Irregular Cadences: Application to VLBI Astrometry of Quasars
Authors: Makarov Valeri V. , Lambert Sébastien , Cigan Phil , DiLullo Christopher , Gordon David 
Published: May 2024

Abstract
Astronomical time series often have non-uniform sampling in time, or irregular cadences, with long gaps separating clusters of observations. Some of these data sets are also explicitly non-Gaussian with respect to the expected model fit, or the simple mean. The standard Lomb–Scargle periodogram is based on the least squares solution for a set of test periods and, therefore, is easily corrupted by a subset of statistical outliers or an intrinsically non-Gaussian population. It can produce completely misleading results for heavy-tailed distribution of residuals. We propose a robust 1-norm periodogram technique, which is based on the principles of robust statistical estimation. This technique can be implemented in weighted or unweighted options. The method is described in detail and compared with the classical least squares periodogram on a set of astrometric VLBI measurements of the ICRF quasar IERS B0642+449. It is uniformly applied to a collection of 259 ICRF3 quasars each with more than 200 epoch VLBI measurements, resulting in a list of 49 objects with quasi-periodic position changes above the 3σ level, which warrant further investigation.
Object condensation for track building in a backward electron tagger at the EIC
Authors: Gardner S. , Tyson R. , Glazier D. , Livingston K. 
Published: May 2024

Abstract
At the Electron Ion Collider, quasi-real photoproduction measurements involve tracking scattered electrons at small angles relative to the beamline. These electrons act as effective beams of tagged almost-real photons, with a high flux compared to larger Q2 interactions. However, the proximity of the detector to the electron beam results in a very high flux of electrons from the bremsstrahlung process (about 10 electrons per 12 ns electron/ion bunch crossing over an area of approximately 100 cm2). Consequently, the tracking detector systems experience high occupancy. To address this, we propose using machine learning algorithms, specifically object condensation methods, which excel at track building in the quasi-real photon tagger. These algorithms achieve track finding efficiency of 95% or higher and purity of 90% or higher, even in the presence of noise and hit detection inefficiencies.