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Graphene-based materials, including graphene oxide (GO) and functionalized derivatives, have demonstrated exceptional potential in addressing environmental challenges related to heavy metal detection and wastewater treatment. This review presents the latest advancements in graphene-based electrochemical and fluorescence sensors, emphasizing their superior sensitivity and selectivity in detecting metal ions, such as Pb2⁺, Cd2⁺, and Hg2⁺, even in complex matrices. The key focus of this review is on the use of molecular dynamics (MD) simulations to understand and predict ion transport through graphene membranes, offering insights into their mechanisms and efficiency in removing contaminants. Particularly, this article reviews the effects of external conditions, pore radius, functionalization, and multilayers on water purification to provide comprehensive insights into filtration membrane design. Functionalized graphene membranes exhibit enhanced ion rejection through tailored electrostatic interactions and size exclusion effects, achieving up to 100% rejection rates for selected heavy metals. Multilayered and hybrid graphene composites further improve filtration performance and structural stability, enabling sustainable, large-scale water purification. However, challenges related to fabrication scalability, environmental impact, and cost remain. This review also highlights the importance of computational approaches and innovative material designs in overcoming these barriers, paving the way for future breakthroughs in graphene-based filtration technologies. [ABSTRACT FROM AUTHOR]

Low Earth orbit (LEO) satellites have emerged as a primary tool for global geomagnetic field detection and model refinement, owing to their wide coverage, high resolution, and absence of geographical limitations. This paper provides a comprehensive review of the history, key characteristics, measurement accuracy, and future trends in LEO satellite magnetic field measurements. The first part of the paper outlines the evolution of LEO satellites, highlighting their unique advantages. The focus then shifts to the calibration methodology for in-orbit LEO satellite magnetic measurements, with a specific emphasis on vector magnetic field intrinsic calibration and alignment algorithms. Calibration results are presented to demonstrate the effectiveness of these methodologies. In the third section, the paper introduces the theory behind global geomagnetic field modeling. An overview of current global geomagnetic field models is provided, encompassing their sources, spatial resolutions, and other relevant attributes. The paper concludes by presenting the global morphology and features of the main field, lithospheric field, magnetospheric, and ionospheric field. Despite the significant progress enabled by LEO satellite technology, global geomagnetic field modeling faces challenges such as limited spatio-temporal resolution. To address this, incorporating near-surface observation data and continuously optimizing modeling technology are deemed essential solutions.

Improvements in heat transfer performance and efficiency through a single heat transfer enhancement technology are limited. Hence, composite-enhanced heat transfer technologies must be developed to improve resource utilization rates and reduce energy consumption and carbon emissions. Refrigerants exhibit physical properties that significantly affect the energy transport in refrigeration systems. Based on the development trend of refrigeration systems characterized by miniaturization, reduced weight, energy savings, and efficient heat transfer, refrigerant composite-enhanced heat transfer can effectively improve the energy efficiency of refrigeration systems, which has been widely studied in recent years. This work summarizes the latest research progress in composite-enhanced flow boiling heat transfer for refrigerants, focusing on nanoparticles, metal foam, external field (ultrasonic/magnetic field/electric field), and environmentally friendly refrigerant mixtures. It also highlights the prospects and existing problems in the application of multi-field synergy and nanoparticle-metal-foam-refrigerant composite-enhanced heat transfer as a future research direction. The review provides insights and references for establishing a new multi-element refrigerant composite-enhanced system.

We introduce a new approach for describing nonstationary quantum systems with a discrete energy spectrum. The essence of this approach is that we describe the evolution of a quantum system in a time-dependent basis. In a sense, this approach is similar to the description of the system in the interaction representation. However, the time dependence of the basic states of the representation is determined not by the evolution operator with a time-independent Hamiltonian but by the eigenstates of the time-dependent Hamiltonian defined at the current time. The time dependence of the basic states of the representation leads to the appearance of an additional term in the Schrödinger equation, which in the case of slowly changing parameters of the Hamiltonian can be considered as a small perturbation. The adiabatic representation is suitable in cases where it is impossible to apply the standard interaction representation. The application of the adiabatic representation is illustrated by the example of two spins connected by a magnetic dipole–dipole interaction in a slowly varying external magnetic field. [ABSTRACT FROM AUTHOR]

Copyright of Reviews of Geophysics & Planetary Physics is the property of Editorial Office of Reviews of Geophysics & Planetary Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Refrigeration is the property of Journal of Refrigeration Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Heavy metal pollution presents significant environmental and public health risks due to its widespread occurrence and resistance to degradation. There is a pressing need for innovative solutions to address the challenge of heavy metal ion removal from water resources. In this review, we highlight recent advancements in emerging catalytic strategies for efficient heavy metal remediation, leveraging various external fields such as electric, mechanical, magnetic, and thermoelectric fields, as well as their synergetic coupling with photocatalysis technology. These novel approaches offer promising avenues for enhancing heavy metal removal efficacy and environmental sustainability. In particular, this review focuses on recent breakthroughs in new materials systems capable of functioning under diverse external fields, heralding future advancements in heavy metal remediation. Finally, we discuss the current challenges and future perspectives in this emerging research area. [ABSTRACT FROM AUTHOR]

Introducing a magnetic-field gradient into an electrically driven chemical reaction is expected to give rise to intriguing research possibilities. In this work, we elaborate on the modes and mechanisms of electrocatalytic activity (from the perspective of alignment of magnetic moments) and selectivity (at the molecular level) for the CO2 reduction reaction in response to external magnetic fields. We establish a positive correlation between magnetic field strengths and apparent current densities. This correlation can be rationalized by the formation of longer-range ordering of magnetic moments and the resulting decrease in the scattering of conduction electrons and charge-transfer resistances as the field strength increases. Furthermore, aided by the magnetic-field-equipped operando infrared spectroscopy, we find that applied magnetic fields are capable of weakening the C–O bond strength of the key intermediate ∗COOH and elongating the C–O bond length, thereby increasing the faradaic efficiency for the electroreduction of CO2 to CO.

We consider several non-standard discrete and continuous Green energy problems in the complex plane and study the asymptotic relations between their solutions. In the discrete setting, we consider two problems; one with variable particle positions (within a given compact set) and variable particle masses, the other one with variable masses but prescribed positions. The mass of a particle is allowed to take any value in the range 0 ≤ m ≤ R , where R > 0 is a fixed parameter in the problem. The corresponding continuous energy problems are defined on the space of positive measures μ with mass ‖ μ ‖ ≤ R and supported on the given compact set, with an additional upper constraint that appears as a consequence of the prescribed positions condition. It is proved that the equilibrium constant and equilibrium measure vary continuously as functions of the parameter R (the latter in the weak-star topology). In the unconstrained energy problem we present a greedy algorithm that converges to the equilibrium constant and equilibrium measure. In the discrete energy problems, it is shown that under certain conditions, the optimal values of the particle masses are uniquely determined by the optimal positions or prescribed positions of the particles, depending on the type of problem considered. [ABSTRACT FROM AUTHOR]

Abstract Rechargeable batteries are essential for the increased demand for energy storage technologies due to their ability to adapt intermittent renewable energies into electric devices, such as electric vehicles. To boost the battery performance, applying external fields to assist the electrochemical process has been developed and exhibits significant merits in energy efficiency and cycle stability enhancement. This perspective focuses on recent advances in the development of external field–assisted battery technologies, including photo‐assisted, magnetic field–assisted, sound field–assisted, and multiple field–assisted. The working mechanisms of external field–assisted batteries and their challenges and opportunities are highlighted.

We present an alternative finite-size scaling (FSS) of the contact process on scale-free networks compatible with mean-field scaling and test it with extensive Monte Carlo simulations. In our FSS theory, the dependence on the system size enters the external field, which represents spontaneous contamination in the context of an epidemic model. In addition, dependence on the finite size in the scale-free networks also enters the network cutoff. We show that our theory reproduces the results of other mean-field theories on finite lattices already reported in the literature. To simulate the dynamics, we impose quasi-stationary states by reactivation. We insert spontaneously infected individuals, equivalent to a droplet perturbation to the system scaling as N − 1 . The system presents an absorbing phase transition where the critical behavior obeys the mean-field exponents, as we show theoretically and by simulations. However, the quasi-stationary state gives finite-size logarithmic corrections, predicted by our FSS theory, and reproduces equivalent results in the literature in the thermodynamic limit. We also report the critical threshold estimates of basic reproduction number R 0 = λ c of the model as a linear function of the network connectivity inverse 1 ∕ z , and the extrapolation of the critical threshold function for z → ∞ yields the basic reproduction number R 0 = 1 of the complete graph, as expected. Decreasing the network connectivity increases the critical R 0 for this model. [ABSTRACT FROM AUTHOR]

We investigate the external field effect on opinion formation based on the majority rule and q -voter models on a complete graph. The external field can be considered as the mass media in the social system, with the probability p agents following the mass media opinion. Based on our Monte Carlo simulation, the mass media effect is not strong enough to make the system reach a homogeneous state (complete consensus) with the magnetization m = 1 for all values of p , indicating the existence of a usual phase transition for all values of p. In the q -voter model, the mass media eliminates the usual phase transition at p ≈ 0. 2 1. We obtain the model's critical point and scaling parameters using the finite-size scaling analysis and obtain that both models have the same scaling parameters. The external field effect decreases both models' relaxation time and the relaxation time following the power-law relation such as τ ∼ N β , where N is the population size and β depends on the probability p. In the majority rule model, β follows a linear relation, and in the q-voter model, β follows a power-law relation. [ABSTRACT FROM AUTHOR]

We explore the connection between supports of equilibrium measures and quadrature identities, especially in the case of point sources added to the external field Q (z) = | z | 2 p with p ∈ N. Along the way, we describe some quadrature domains with respect to weighted area measure | z | 2 p d A z and complex boundary measure | z | − 2 p d z. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) has been used to study the structure and electronic properties of boron-doped armchair germanene nanoribbons materials. The doped configurations are all stable in the electric field by the σ bond and the π bond. The doped structures can be semi-conductive or semi-metallic depending on the doping substitution positions. The doping configuration B:Ge = 1:1 proved to be superior and stable in the electric field, and the doping changed this structure to become planar. With three different directions of electric field, the horizontal electric field has the most influence on the geometric structure, multi-orbit hybridization as well as the spatial charge distribution of the doped systems. The magnetization of the systems changes with the changing direction of an electric field, anti-ferromagnetic structures are found in meta-configuration and ortho-configuration with longitudinal electric fields, and 1–1 configuration with perpendicular electric fields and horizontal electric fields. The ortho-configuration with an electric field of 0.5 V/m with an extended band gap of 0.69 eV is perfectly applicable in room-temperature field-effect transistors; other configurations have potential in nanoscale applications. [ABSTRACT FROM AUTHOR]

The magnetic field as a "non-contact" external field can instantaneously affect the separation and migration of photogenerated carriers during the photocatalytic reaction. This facilitates the large-scale industrial application of photocatalysis technology. Consequently, the potential for using external magnetic fields to enhance photocatalysis in environmental pollution control and clean energy production has received significant attention. Herein, the principle of the magnetic field acting on photocatalytic reaction is discussed, including spin polarization, the Lorentz force, negative magnetoresistance, and electromotive force. In particular, the typical reaction devices and magnetic field settings involved in current research on magnetic field-assisted photocatalysis are exhibited. Meanwhile, the performance of magnetic field-assisted photocatalysis in specific applications is presented. The efficiency and experimental parameters of catalysts are classified and organized by their specific application fields. It is highlighted to summarize and interpret the mechanisms underlying magnetic field-assisted photocatalysis presented in previous studies, along with the latest validation techniques. Finally, the challenges and potential opportunities are discussed. This review offers valuable insights and guidance for the design and development of innovative magnetic field-assisted photocatalytic systems, thereby accelerating the industrial application of photocatalytic technology., (© 2025 Wiley‐VCH GmbH.)

Up to now, post-annealing is most commonly used to post treat the perovskite film to accelerate the ripening process. Nonetheless, the top-down crystallization mechanism impedes the efficient desolvation of solvent complexes. Thus, residual solvent complexes tend to accumulate at the bottom of the film during the ripening process and deteriorate the device. Here, a new strategy with unique concept is promoted to amplify ripening process of perovskite film, in which a nematic thermotropic liquid crystal (LC) molecular is introduced to facilitate the conversion of solvent complexes by utilizing the liquid crystalline behavior under external field. Upon the concurrent application of thermal and force fields, the covalent interaction between LC and solvent complexes generates a driving force, which promotes upward migration of solvent complexes, thereby facilitating their engagement in the ripening process. In addition, the driving force under external fields assists the flattening of grain boundary grooves. Therefore, film quality is improved efficiently with amplified ripening process and adequately handled buried interface. Based on the positive effects, the devices achieve a champion efficiency of 25.24%, and sustained ≈75% of its initial efficiency level even after undergoing a damp heat test (85 °C/85% RH) for 1400 h., (© 2024 Wiley‐VCH GmbH.)

In this paper, we study the phase transition phenomenon for the three-state solid-on-solid (SOS) model on a Cayley tree under a non-uniform external field. [ABSTRACT FROM AUTHOR]

The hybrid architecture of the driven qubit–photon–magnon system has recently emerged as a promising candidate for novel quantum technologies. In this paper, we introduce the effective wave-function of a superconducting single qubit and a magnon mode contained within a cavity resonator and an external field. The non-classicality of the magnon and resonator modes are investigated by using the negative values of the Wigner function. Additionally, we discuss the non-classicality of the qubit state via the Wigner–Yanase skew information. We find that the mixture angle of the qubit–resonator plays a controllable role in non-classicality. However, the strength of the magnon–photon increases the non-classical behaviour of the system. [ABSTRACT FROM AUTHOR]

In this paper, we investigated the propagation of the modulated waves (MWs) patterns with the effects of the external field (EF) in a photorefractive crystal. To do so, we use the coupled nonlinear Schrödinger equations and we apply the auxiliary equation method to point out four families of solutions such as bright, dark, combined bright-dark, and bright-bright soliton. We pointed out the effects of EF on the modulation instability growth rate. Throughout the numerical simulation, we show that EF can generate MWs patterns when the short and open circuit condition is considered in the case of bright soliton. However, when we consider dark soliton solution as an initial condition and we have only obtained the MW pattern in the case of a short circuit. It results in this study of the propagation of the MWs patterns and chaos-like motion for specific cell indexes. [ABSTRACT FROM AUTHOR]

We consider a three-state solid-on-solid (SOS) model in the presence of nonzero external field on a Cayley tree. We obtain a system of functional equations for this model, which each positive solution of the system corresponds to a splitting Gibbs measure. Using this, we study the translation-invariant splitting Gibbs measures (TISGMs) of the model. On the binary tree, we find all the TISGMs of the model. [ABSTRACT FROM AUTHOR]

[Display omitted] • The application areas and reinforcement mechanisms of different external fields are summarized. • Synergy of multiple effects from an individual field and synergy of multiple fields are discussed. • The existing challenges and future research directions in the field of field-assisted electrochemistry are indicated. Of late years, external field enhanced electrochemistry has emerged as an innovative approach with promising potential for achieving highly effective energy conversion and storage. In electrochemical reactions, various external fields have been demonstrated to exert beneficial impacts, whether directly or indirectly. From the aspects of system design and mechanism, the regulating effects on mass transfer and energy conversion of diverse external fields, consisting of magnetic, light, thermal, acoustic and gravity fields, are systematically summarized in the paper. Ultimately, the main challenges facing this regulatory strategy in the external field and the differences and connections between each field are discussed. We sincerely expect that this review will not only provide a novel insight into the fundamental mechanism of external field-assisted electrochemical reaction, such as electrocatalysis, electrodeposition, etc., but also foster further research in the field of sewage disposal, metal corrosion protection, green synthesis, and energy storage from a more diverse and comprehensive perspective. [ABSTRACT FROM AUTHOR]

We consider a three-state solid-on-solid (SOS) model on a Cayley tree in the presence of an external field. We show that periodic Gibbs measures are either translation invariant or periodic with period two. We describe two-periodic Gibbs measures of the model. [ABSTRACT FROM AUTHOR]

The microfluidic systems' thermal performance in various industries is affected by the fluid flow within their micro/nanochannels. This study aimed to investigate the boiling process of samples simulated in micro/nanochannel by molecular dynamics simulation. In the present study, the boiling time inside the micro/nanochannel is investigated at different types of base fluid (Helium, oxygen (air), and water), different types of channels walls particles (copper, platinum, and copper/platinum), number of atomic curvatures (1, 2, and 3), external electric field (1, 2, and 5 V/m), and external magnetic fields (1, 2, and 5 T). Numerically, the phase change rate in Helium base fluid samples is higher than other fluids. Its boiling time in micro/nanochannels was 3.88 and 3.54 ns, respectively. This indicates an increase in these structures' efficiency in constructing heat transfer processes. In addition, the boiling time of the base fluid in the platinum atomic micro/nanochannels occurs in a shorter time of 3.61 and 3.52 ns. By increasing the number of curves from 1 to 3 complete curvatures, the micro/nanochannel's boiling time decreases from 3.88/3.54 to 3.07/2.89 ns. Also, by increasing the intensity of the external electric field from 0 to 5 V/m, the boiling time in the micro/nanochannel decreases from 3.88/3.84 ns to 3.21/3.16 ns. Finally, increasing the intensity of the external magnetic field from 0 to 5 T leads to a decrease in boiling time in the micro/nanochannel to 3.10/3.02 ns. This phenomenon indicates an increase in mobility and kinetic energy of the base fluid by applying the external field.

Tailoring martensite transformation is critical for improving the mechanical properties of advanced steels. To provide preliminary guidance for the control of martensite transformation behaviour using external fields by computational simulation method, the phase-field method was used to calculate the morphology evolution, kinetics, and variant selection of the martensite transformation under different loading modes and magnetic field intensities. The incubation, transformation, and stable stages of the three variants based on the Bain strain group were investigated using different kinetic curves. These results clearly indicate that both uniaxial tension and compression can greatly promote the formation of martensite during the transformation stage and cause an obvious preferred variant selection. In contrast, the different variants have relatively balanced forms under shearing conditions. In addition, the magnetic field is a gentler way to form a state with balanced variants than other techniques such as shearing. Additionally, all these simulation results are consistent with classical martensitic transformation theory and thermodynamic mechanism, which proves the rationality of this research. The aim of the present study was to provide qualitative guidance for the selection of external fields for microstructural improvement in advanced steels. [ABSTRACT FROM AUTHOR]

Background: The aetiology of internalising disorders remains poorly understood. Recently, a bottom-up network perspective has suggested mental disorders are best conceptualised as emergent systems, and may be explained by mapping systems of symptoms embedded within a complex biopsychosocial environment. Under this framework, the complex system in which internalising disorders are embedded remains poorly understood. The present research outlines a brief psychosocial system of internalising disorders as a basis for future research.Methods: A Mixed Graphical Model was fitted on 15 psychosocial variables (including depression and anxiety) collected during the Christchurch Health and Development Study, a representative population birth cohort of 1265 people born in 1977 in Christchurch, New Zealand.Results: The model demonstrates that psychosocial risk factors for internalising disorders tend to be inter-related. The psychosocial system accounted for 19.9% of the variance in the diagnostic depression variable, and 5.0% of the variance in diagnostic anxiety. Most variables (10/13) were associated with depression and anxiety either directly or indirectly.Limitations: First, the estimated model is undirected, so causal directions are unspecified except for longitudinal relationships. Second, binary diagnostic variables were used for depression and anxiety, meaning the model does include symptom-level complexity. Third, the model does not account for within-person effects.Conclusions: This exploratory model may serve as a basis for the mapping of greater (bio) psychosocial complexity around internalising disorders. The model concisely demonstrates the need for researchers to "embrace complexity", but also underscores the conceptual scope that is required to do so on a broader (bio) psychosocial level. [ABSTRACT FROM AUTHOR]

The synchrotron radiation technology has recently emerged as a powerful tool to characterize the real-time microstructure evolution during solidification of alloys. Compared with other methods, the synchrotron radiation technology, along with its unique advantages of strong brightness, high energy, excellent resolution, and good monochromaticity, allows for capturing the dendrite evolution behavior of alloys in real time and can be dynamically coordinated with high-resolution CCD (Charge-coupled Device) imaging systems. This paper briefly reviews the recent advances in developing synchrotron radiation for solidification of alloys with low, medium, and high melting points, and under the external electric, magnetic, and ultrasonic fields. Furthermore, a series of microstructural features and behaviors such as dendrite morphology, growth orientation, dendrite fracture, and rotation are described in detail. Finally, the development trends and application prospects of synchrotron radiation technology in alloy solidification are forecasted.

In QED, an external electromagnetic field can be accounted for non-perturbatively by replacing the causal propagators used in Feynman diagram calculations with Green’s functions for the Dirac equation under the external field. If the external field destabilises the vacuum, then it is a difficult problem to determine which Green’s function is appropriate, and multiple approaches have been developed in the literature whose equivalence, in many cases, is not clear. In this paper, we demonstrate for a broad class of external fields that includes all that act for a finite time, that four Green’s functions used in the literature are equivalent: Schwinger’s “proper-time” propagator; the “causal propagator” used in the “Bogoliubov transformation” method based on the canonical quantization of the field operator; and two defined using analytic continuation from complexified parameters. To do so, we formulate Schwinger’s “proper-time quantum mechanics" as a Schrödinger wave mechanics, and use this to re-derive Schwinger’s expression for the propagator as a statement relating solutions of the inhomogeneous Dirac equation to those of the inhomogeneous “proper-time Dirac equation”. This is done by constructing direct integral spectral decompositions of the Hamiltonians of both equations, and deriving a form for solutions of the inhomogeneous Dirac equation in terms of these decompositions. We then show that all four propagators return solutions of the inhomogeneous Dirac equation that satisfy the same boundary condition, which under a physically reasonable assumption is sufficient to specify the solution uniquely. [ABSTRACT FROM AUTHOR]

Privileged photocatalysts combine semiconductor physics, materials science, chemical engineering and environmental science to convert abundant photonic energy into chemical energy. A common limitation of photocatalysts at-scale processes is their insufficient light absorption capability and charge carrier management. Additionally, the potential secondary pollution and difficulties in effective recovery associated with the dispersion of traditional powder catalysts in the water further limit their industrial application. To address these issues, strong electric fields generated by the piezoelectric effect were introduced to reduce the scattering probability of photoinduced carriers during their migration, thereby significantly enhancing photocatalytic efficiency. Specifically, we have developed a PDMS-loaded solid solution 0.7 BiFeO 3 -0.3 BaTiO 3 (BFBT) hybrid catalyst that achieves a degradation rate of 99% for Rhodamine B solution within 60 min under the synergistic action of low-frequency vibration and light irradiation. The degradation kinetic constant was 0.080 min−1, representing a piezoelectric enhancement of photocatalysis by 148%. The internal electric field is excited by periodic mechanical stress, which finely regulates the interface energy band structure, promotes the effective separation of photoinduced carriers and enhances the generation of reactive oxygen species, thereby strengthening the chemical reaction kinetics and achieving efficient degradation of pollutants. [Display omitted] • Design narrow bandgap BFBT-PDMS heterojunction material based on ABO 3 framework. • Introduce PDMS solid supports for nanoparticle encapsulation to tackle secondary pollution & limited catalyst reusabilit. • Construct a piezo-photocatalytic system through the integration of mechanical stress and polarization. [ABSTRACT FROM AUTHOR]

The dynamics of colloidal particles at infinite dilution, under the influence of periodic external potentials, is studied here via experiments and numerical simulations for two representative potentials. From the experimental side, we analyzed the motion of a colloidal tracer in a one-dimensional array of fringes produced by the interference of two coherent laser beams, providing in this way an harmonic potential. The numerical analysis has been performed via Brownian dynamics (BD) simulations. The BD simulations correctly reproduced the experimental position- and time-dependent density of probability of the colloidal tracer in the short-times regime. The long-time diffusion coefficient has been obtained from the corresponding numerical mean square displacement (MSD). Similarly, a simulation of a random walker in a one dimensional array of adjacent cages with a probability of escaping from one cage to the next cage is one of the most simple models of a periodic potential, displaying two diffusive regimes separated by a dynamical caging period. The main result of this study is the observation that, in both potentials, it is seen that the critical time t*, defined as the specific time at which a change of curvature in the MSD is observed, remains approximately constant as a function of the height barrier U0 of the harmonic potential or the associated escape probability of the random walker. In order to understand this behavior, histograms of the first passage time of the tracer have been calculated for several height barriers U0 or escape probabilities. These histograms display a maximum at the most likely first passage time t′, which is approximately independent of the height barrier U0, or the associated escape probability, and it is located very close to the critical time t*. This behavior suggests that the critical time t*, defining the crossover between short- and long-time regimes, can be identified as the most likely first passage time t′ as a first approximation.

Ferrite nanoparticles have been widely used in the biomedical field (such as magnetic targeting, magnetic resonance imaging, magnetic hyperthermia, etc.) due to their appealing magnetic properties. In tumor acidic microenvironment, ferrite nanoparticles show intrinsic peroxidase-like activities, which can catalyze the Fenton reaction of hydrogen peroxide (H2O2) to produce highly toxic hydroxyl free radicals (•OH), causing the death of tumor cell. Recent progresses in this field have shown that the enzymatic activity of ferrite can be improved via converting external field energy such as alternating magnetic field and near-infrared laser into nanoscale heat to produce more •OH, enhancing the killing effect on tumor cells. On the other hand, combined with other nanomaterials or drugs for cascade reactions, the production of reactive oxygen species (ROS) can also be increased to obtain more efficient cancer therapy. In this review, we will discuss the current status and progress of the application of ferrite nanoparticles in ROS-mediated cancer therapy and try to provide new ideas for this area.

We analyze the free energy and the overlaps in the 2-spin spherical Sherrington Kirkpatrick spin glass model with an external field for the purpose of understanding the transition between this model and the one without an external field. We compute the limiting values and fluctuations of the free energy as well as three types of overlaps in the setting where the strength of the external field goes to zero as the dimension of the spin variable grows. In particular, we consider overlaps with the external field, the ground state, and a replica. Our methods involve a contour integral representation of the partition function along with random matrix techniques. We also provide computations for the matching between different scaling regimes. Finally, we discuss the implications of our results for susceptibility and for the geometry of the Gibbs measure. Some of the findings of this paper are confirmed rigorously by Landon and Sosoe in their recent paper which came out independently and simultaneously. [ABSTRACT FROM AUTHOR]

• Continuum-statistical model to predict interfacial deformation under a variety of external fields. • Redistribution of molecules under the field alters the interaction potentials to engender interfacial deformation. • Local interfacial deformations are correlated to the effects of fields on the redistribution of molecules. • The analytical model is successfully integrated with the Cahn-Hilliard and Navier-Stokes framework. • Simulated results accurately predict the pre-existing experimental and theoretical results. Coupling the continuum approach with a statistical one may help in the development of a generic thermodynamic model to theoretically analyse the variations of interfacial tension and subsequent deformation of an interface between a pair of fluids under a field exposure. In this direction, the local variations of interfacial tension due to the redistribution of interfacial molecules have been expressed as the functions of the molecular interaction potentials for a variety of externally applied fields. Two continuum-statistical models for interfacial tension have been developed by choosing two different types of molecular interaction potentials. The proposed analytical models have been successfully integrated with the Cahn-Hilliard and Navier-Stokes framework before solving them numerically using computational tools. Effects of field exposure on the redistribution of the molecules and the molecular interaction potentials can be correlated to the local variations of the interfacial tension and interfacial deformations. The calculations related to the temperature dependence of interfacial thickness and interfacial tension matches well with the experimental data. The simulated results show a nearly accurate prediction of the pre-existing experimental and theoretical results on interfacial deformation under electric, magnetic and optical fields. [ABSTRACT FROM AUTHOR]

Polymer-based nanocomposites with excellent flexibility and intrinsic high breakdown strength are promising candidates for high energy density capacitors compared to ceramics counterparts. However, their energy density is relatively low due to the trade-off between permittivity and breakdown strength. In this work, the authors proposed a ferroconcrete-like structure for all-organic nanocomposites via combinatorial electrospinning and hot-pressing method. In this structure, polymethyl methacrylate (PMMA) serves as matrix while poly(vinylidene fluoride-co-hexafluoropropylene) (P(VDF-HFP)) serves as reinforcement phase. This novel structure is highly effective in breaking the paradox of improved discharged energy density with decreased efficiency, as evidenced by the concurrently improved discharged energy density (∼12.15 J/cm^3 compared to 8.82 J/cm^3 of the matrix) and efficiency (∼81.7% compared to 76.8% of the matrix). Compared to conventional blending composite films, samples with ferroconcrete-like structure exhibit higher permittivity, breakdown strength, discharged energy density and efficiency. The superior energy storage performance is attributed to large aspect ratio P(VDF-HFP) fibres distributed perpendicularly to the external field, which brings about the extra enhancement of permittivity. Besides, mechanical properties are improved and restriction on carrier motion is facilitated, leading to enhanced breakdown strength and suppressed conduction. This work provides a new way to design dielectric composite for high energy density and efficiency applications.

This paper examines the squeezing on information entropy and entanglement on the basis of a quantum scheme that contains two-mode interaction with time dependence of a two-level atom, including the external field. The proposed model is formulated by eliminating the external field after applying a certain transformation. The dynamics of information entropy squeezing and non-local correlation information for the system Hamiltonian are investigated. The effect of the evolution of the squeezing and entanglement by the classical field are estimated. Based on the results, the obtained dynamic behavior of squeezing and entanglement is controlled using the external field.

Tailoring martensite transformation is critical for improving the mechanical properties of advanced steels. To provide preliminary guidance for the control of martensite transformation behaviour using external fields by computational simulation method, the phase-field method was used to calculate the morphology evolution, kinetics, and variant selection of the martensite transformation under different loading modes and magnetic field intensities. The incubation, transformation, and stable stages of the three variants based on the Bain strain group were investigated using different kinetic curves. These results clearly indicate that both uniaxial tension and compression can greatly promote the formation of martensite during the transformation stage and cause an obvious preferred variant selection. In contrast, the different variants have relatively balanced forms under shearing conditions. In addition, the magnetic field is a gentler way to form a state with balanced variants than other techniques such as shearing. Additionally, all these simulation results are consistent with classical martensitic transformation theory and thermodynamic mechanism, which proves the rationality of this research. The aim of the present study was to provide qualitative guidance for the selection of external fields for microstructural improvement in advanced steels.

Single‐molecule devices, which are fabricated by the single molecule bridged through electrodes, provide a promising approach to investigate the intrinsic chemical or physical properties of individual molecules. Beyond the studies of single‐molecule wires, a large number of responsive single‐molecule junctions or devices with unique chemical or physical properties have been designed and fabricated by introducing the external field, which further offers the chance to explore conductive materials at the molecular level. Here, we summarized the latest studies on the behaviors of single‐molecule devices based on the photon, thermal, electric, or magnetic responses, and discussed the development of responsive single‐molecule devices in prospect. [ABSTRACT FROM AUTHOR]

The synchrotron radiation technology has recently emerged as a powerful tool to characterize the real-time microstructure evolution during solidification of alloys. Compared with other methods, the synchrotron radiation technology, along with its unique advantages of strong brightness, high energy, excellent resolution, and good monochromaticity, allows for capturing the dendrite evolution behavior of alloys in real time and can be dynamically coordinated with high-resolution CCD (Charge-coupled Device) imaging systems. This paper briefly reviews the recent advances in developing synchrotron radiation for solidification of alloys with low, medium, and high melting points, and under the external electric, magnetic, and ultrasonic fields. Furthermore, a series of microstructural features and behaviors such as dendrite morphology, growth orientation, dendrite fracture, and rotation are described in detail. Finally, the development trends and application prospects of synchrotron radiation technology in alloy solidification are forecasted. [ABSTRACT FROM AUTHOR]

Spin squeezed state, as an important quantum resource, can be used to implement the high precise measurement beyond the standard quantum limit. Based on the recent novel scheme that strong magnetomechanical interaction between a single Nitrogen-vacancy (NV) spin and the vibrational mode of the suspended nanotube is engineered (Li et al. Phys. Rev. Lett. 117, 015502 2016), we investigate the steady-state spin squeezing behaviors of a spin ensemble in diamond coupled to carbon nanotubes by exerting a controllable microwave field. We show that steady-state spin squeezing can be generated with the help of the microwave field, despite the damping from mechanical damping. This investigation based on spin-spin interaction in diamond might apply to magnetometers, interferometry, and other precision measurement measurements. [ABSTRACT FROM AUTHOR]

In 2017, the second generation of the Joule balance achieved a measurement uncertainty of $2.4 \times 10^{-7}$. The main source of the uncertainty is identified as the effect of the external field, resulting in $1.7 \times 10^{-7}$ in the uncertainty budget. Hence, two solutions are proposed in the Joule balance to eliminate the effect of the external field, i.e., the magnetic shielding and compensation coils. This paper first gives an overview of the constructions of the shield and the compensation coils. Then, the flux linkage difference of the external field is measured under different conditions. Last, the effect of the two solutions is verified through the experiments. Based on the measurement results, it can be found that the uncertainty resulting from the effect of the external field in the Joule balance will be reduced to $1.4 \times 10^{-8}$ when the two solutions are applied. [ABSTRACT FROM AUTHOR]

We consider a nearest-neighbor solid-on-solid (SOS) model, with several spin values 0, 1, 2, ..., m,m ⩾ 2 and non zero external field, on a Cayley tree of order k. In the case k = 2,m = 2, we describe translation-invariant ground states for the SOS model with a translation-invariant external field. Some periodic ground states for the SOS model with periodic external field are described. [ABSTRACT FROM AUTHOR]