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Black phosphorus (bP) is a promising material for mid-infrared (mid-IR) optoelectronic applications, exhibiting high performance light emission and detection. Alloying bP with arsenic extends its operation toward longer wavelengths from 3.7 μm (bP) to 5 μm (bP3As7), which is of great practical interest. Quantitative optical characterizations are performed to establish black phosphorus-arsenic (bPAs) alloys optoelectronic quality. Anisotropic optical constants (refractive index, extinction coefficient, and absorption coefficient) of bPAs alloys from near-infrared to mid-IR (0.2-0.9 eV) are extracted with reflection measurements, which helps optical device design. Quantitative photoluminescence (PL) of bPAs alloys with different As concentrations are measured from room temperature to 77 K. PL quantum yield measurements reveal a 2 orders of magnitude decrease in radiative efficiency with increasing As concentration. An optical cavity is designed for bP3As7, which allows for up to an order of magnitude enhancement in the quantum yield due to the Purcell effect. Our comprehensive optical characterization provides the foundation for high performance mid-IR optical device design using bPAs alloys.

To ensure long-term safety and performance, geological nuclear waste repositories require low-permeability barriers such as bentonite buffers and/or shale host rock. Shale is not only known for its low permeability but also for its trend to undergo time-dependent deformation (i.e., creep), which could heal damage, but the effects of shale creep on the long-term performance of nuclear waste repositories have not been clearly understood. In particular, the anisotropic nature of shale (i.e., bedding) could have a significant effect on its creep behavior, and consequently, on the long-term performance of nuclear waste repositories. In this research, numerical simulations were carried out with the objective of showing the effects of anisotropic shale creep on the stress and permeability evolution of a generic geological nuclear waste repository in shale. The TOUGH-FLAC simulator, a thermo-hydromechanically (THM) coupled numerical code, was used for the simulations. To achieve the objective, comparisons were performed between the results of anisotropic shale creep simulations and those of different simulation cases, namely, no creep (i.e., elastic), isotropic creep, and long-term creep shale cases. Results of the comparisons show that the elastic and isotropic creep shale cases respectively led to the overestimation and underestimation of stress and permeability in the repository, whereas the long-term creep shale case, which accumulated greater creep in later periods than in earlier periods, helped to keep large shear and tensile stresses from developing while maintaining compressive spherical stress, resulting in consistently low permeability levels. These results indicate that performance assessments with elastic and isotropic creep formation models will provide the upper and lower bound estimates of stress and permeability, while more reasonable estimates will be given by an anisotropic creep formation model, and that shale with long-term creep characteristics will be beneficial in many aspects of the safety and performance of nuclear waste repositories.

This paper focuses on the three‐dimensional (3D) incompressible anisotropic Boussinesq system while the velocity of fluid only involves horizontal dissipation and the temperature has a damping term. By utilizing the structure of the system, the energy methods and the means of bootstrapping argument, we prove the global stability property in the Sobolev space Hk(ℝ3)(k≥3)$$ {H}^k\left({\mathrm{\mathbb{R}}}^3\right)\left(k\ge 3\right) $$ of perturbations near the hydrostatic equilibrium. Moreover, we take an effective approach to obtain the optimal decay rates for the global solution itself as well as its derivatives. In this paper, we aim to reveal the mechanism of how the temperature helps stabilize the fluid. Additionally, exploring the stability of perturbations near hydrostatic equilibrium may provide valuable insights into specific severe weather phenomena. [ABSTRACT FROM AUTHOR]

This study examines nonnegative solutions to the problem { Δ u = λ | x | α u p in R 2 ∖ { 0 } , u (0) = 0 and u > 0 in R 2 ∖ { 0 } , where λ > 0 , α > − 2 , and p > 0 are constants. The possible asymptotic behaviors of u (x) at | x | = 0 and | x | = ∞ are classified according to (α , p). In particular, the results show that for some (α , p) , u (x) exhibits only "isotropic" behavior at | x | = 0 and | x | = ∞. However, in other cases, u (x) may exhibit the "anisotropic" behavior at | x | = 0 or | x | = ∞. Furthermore, the relation between the limit at | x | = 0 and the limit at | x | = ∞ for a global solution is investigated. [ABSTRACT FROM AUTHOR]

Real-time digital image correlation (DIC) experiments were performed during three-point bending tests of shale with 7 bedding angles and 5 sizes to investigate the anisotropic fracture behavior and size effect. The results revealed that the bedding plane orientation significantly influenced the fracture propagation. Microcracks at the crack tip and the subsequent fracture of the shale specimens with bedding angles of 0° and 90° were primarily attributed to tensile strain. In contrast, the shear strain and its effect on crack initiation and propagation in specimens were higher at bedding angles from 15° to 75°. The relationship curve between the dominant crack parameter (DCP) and the bedding angle had a V-shape. DCP values greater than 2.51 (0° ≤ β < 45°, β = 90°) indicated minimal shear effects, resulting in crack propagation in the original direction, whereas values less than 2.51 (45° ≤ β ≤ 75°) implied crack deviation toward the bedding plane due to shear effects. Furthermore, the fracture parameters, including the critical crack tip opening displacement, inelastic zone length (lr), fracture process zone (FPZ) length (lFPZ), and effective FPZ length (cf), exhibited a W-shaped trend with bedding angle. The values decreased and increased in two stages with a bedding angle of 45° as the demarcation point. The size effect was pronounced; lFPZ increased linearly with the specimen size; lr increased with the specimen size, but the growth rate was lower. DIC analysis accurately reflected the anisotropic characteristics of crack evolution and strain concentration zone. However, the FPZ length derived from DIC was larger than the theoretical results obtained from nonlinear fracture mechanics and Bažant's size effect law. This discrepancy was attributed to the fact that the FPZ derived from DIC included marginal regions with minimal microcracks and strain concentration. Highlights: Real-time digital image correlation experiments were performed during three-point bending tests of shale with 7 bedding angles and 5 sizes. The bedding plane orientation significantly influenced the crack propagation in shale, with shear strain playing a key role. The critical crack tip opening displacement and the FPZ length had a W-shaped trend with the bedding angle. The lengths of FPZ and inelastic zone increased with the specimen size, affecting the energy dissipation during shale fracture. The FPZ length derived from DIC was larger than the theoretical results obtained from nonlinear fracture mechanics and the size effect law. [ABSTRACT FROM AUTHOR]

This study aims to observe the crashworthiness performance of a double-hat column constructed from anisotropic sheet metals under axial impact conditions. The predicted crashworthiness parameters obtained from numerical simulations were compared with experimental data. Anisotropy was discerned through the examination of three material orientations. The effects of viscoplasticity were rigorously investigated under both quasi-static and dynamic loading conditions. Anisotropy notably exerted a pronounced influence on crucial metrics such as mean crushing force, maximum crushing force, and specific energy absorption. Furthermore, the viscoplastic behavior of the column substantially augmented the structural response, particularly under dynamic loading scenarios. Notably, the anisotropic-viscoplastic model exhibited superior accuracy compared to its isotropic counterpart, thereby underscoring its efficacy in capturing intricate material characteristics. This study underscores the critical significance of accounting for geometric imperfections to ensure precise predictions of deformation shapes and crashworthiness performance. [ABSTRACT FROM AUTHOR]

This article introduces an approximate two-dimensional (2D) approach to analyze the static behavior of elastic plates composed of functionally graded materials (FGM) exhibiting anisotropic characteristics. The methodology employed involves the refined Higher Order Shear and Normal Deformation Theory (HOSNT12), which incorporates a comprehensive set of 12 degrees of freedom in displacement field. In this analytical framework, it is assumed that the mechanical properties of the plate vary exponentially throughout its thickness. Five distinct exponential variations are applied to modify the stiffness matrix of the plate. The resulting findings are compared to the exact solution, demonstrating a satisfactory level of precision. [ABSTRACT FROM AUTHOR]

In this paper, we investigated new solutions for the anisotropic compact stellar model in Einstein–Gauss–Bonnet (EGB) theory. In this context, we established a set of field equations with the help of anisotropic matter configuration. The relation between pressure in the radial direction and the energy density is taken by using a linear equation of state (EoS). A well-known Boulware–Deser exterior spacetime is matched with interior spherically symmetric spacetime at the boundary of the star to determine the unknown parameters. Different physical parameters are investigated, namely, these are density, radial pressure and transversal pressure, anisotropy, mass function, compactness and surface redshift. We discussed Herrera’s cracking condition, Tolman–Oppenheimer–Volkoff (TOV), and the adiabatic index. The values of some physical quantities like density (at center and surface), compactness and surface redshift are calculated numerically for three compact stars PSR J0348+0432, PSR J0740+6620 and PSR J0030+0451. A graphical analysis of these physical quantities for a representative compact star candidate PSR J0348+0432 is also presented with various values of EGB parameter α. The energy conditions for anisotropic compact star PSR J0348+0432 are satisfied, surface redshift remains within the limit and also all the stability conditions that we discussed in this work are satisfied, this validates our presented model. The effects of the GB coupling parameter α on the physical parameters are depicted graphically and numerically. [ABSTRACT FROM AUTHOR]

Understanding wildfire spread in Canada is critical to promoting forest health and protecting human life and infrastructure. Quantifying fire spread from noisy images, where change-point boundaries separate regions of fire, is critical to accurately estimating fire spread rates. The challenge lies in denoising the fire images and accurately identifying highly non-linear fire lines without smoothing over boundaries. In this paper, we develop an iterative smoothing algorithm for change-point data that utilizes oversmoothed estimates of the underlying data generating process to inform re-smoothing. We demonstrate its effectiveness on simulated one- and two-dimensional change-point data, and robustness to response outliers. Then, we apply the methodology to fire spread images from laboratory micro-fire experiments and show that the regions fuel, burning and burnt-out are smoothed while boundaries are preserved. [ABSTRACT FROM AUTHOR]

AbstractThis paper provides a comprehensive analysis of the undrained failure envelope for embedded foundations in anisotropic clays. Using the AUS failure criterion as the soil strength model, the study examines how the anisotropic strength (re) and embedment depth (D/B) affect the behavior of the footing under combined loading conditions. Failure envelopes are assessed via two-dimensional finite element limit analysis (2D FELA) in both 2D and 3D spaces. This research highlights the failure mechanisms of embedded foundations, offering valuable insights into the engineering design of footings in anisotropic clays subjected to combined loads (V, H, M). Furthermore, this study introduces an advanced soft-computing approach by creating a machine learning model that leverages the adaptive neuro-fuzzy inference system (ANFIS) integrated with the particle swarm optimization (PSO) algorithm to predict the failure envelope of embedded footings, highlighting the novelty and original of this study. The optimised ANFIS model has been validated and demonstrates a strong correlation with the numerical FELA results, offering engineers a valuable tool for determining the failure envelope of embedded foundations in anisotropic clay under different loading scenarios (V, H, M). [ABSTRACT FROM AUTHOR]

The weak intermolecular forces of hydrogen‐bonded organic frameworks (HOFs) make it relatively difficult to synthesize and design HOFs with superprotonic conductivity and robustness. The self‐assembly of ionic hydrogen bonding organic frameworks (iHOFs) through acid–base pairing strategies are possible on account of the rich hydrogen bonding, strong ionic bonding, and π–π stacking interactions and so on. Herein, a case of iHOF (iHOF‐16) with a three‐dimensional (3D) hydrogen bonding network is reported, the doughty ionic bond interactions in the structure and π–π stacking interactions between layers make it exhibits excellent thermal and chemical stability, it can maintain high crystallinity and robust structure even under extreme conditions. Importantly, iHOF‐16 exhibits highly anisotropic proton conductivity of 0.388, 5.56 × 10−3, and 3.25 × 10−4 S cm−1 in the direction of a‐axis, b‐axis, and c‐axis, respectively. The proton transfer paths of single crystal on each axis are calculated using density functional theory (DFT) and, supported by joint experimental–theoretical calculations, protons are most easily transported in the a‐axis direction resulting in superprotonic conductivity. The present study provides a promising approach for the design of stable superprotonic conductivity materials through a simple yet effective charge‐assisted synthesis strategy. [ABSTRACT FROM AUTHOR]

The weak intermolecular forces of hydrogen‐bonded organic frameworks (HOFs) make it relatively difficult to synthesize and design HOFs with superprotonic conductivity and robustness. The self‐assembly of ionic hydrogen bonding organic frameworks (iHOFs) through acid–base pairing strategies are possible on account of the rich hydrogen bonding, strong ionic bonding, and π–π stacking interactions and so on. Herein, a case of iHOF (iHOF‐16) with a three‐dimensional (3D) hydrogen bonding network is reported, the doughty ionic bond interactions in the structure and π–π stacking interactions between layers make it exhibits excellent thermal and chemical stability, it can maintain high crystallinity and robust structure even under extreme conditions. Importantly, iHOF‐16 exhibits highly anisotropic proton conductivity of 0.388, 5.56 × 10−3, and 3.25 × 10−4 S cm−1 in the direction of a‐axis, b‐axis, and c‐axis, respectively. The proton transfer paths of single crystal on each axis are calculated using density functional theory (DFT) and, supported by joint experimental–theoretical calculations, protons are most easily transported in the a‐axis direction resulting in superprotonic conductivity. The present study provides a promising approach for the design of stable superprotonic conductivity materials through a simple yet effective charge‐assisted synthesis strategy. [ABSTRACT FROM AUTHOR]

The complex multiscale and anisotropic nature of silicon carbide (SiC) ceramic matrix composite (CMC) makes it difficult to accurately model its performance in nuclear applications. The existing models for nuclear grade composite SiC do not account for the microstructural features and how these features can affect the thermal and structural behavior of the cladding and its anisotropic properties. In addition to the microstructural features, the properties of individual constituents of the composites and fiber tow architecture determine the bulk properties. Models for determining the relationship between the individual constituents' properties and the bulk properties of SiC composites for nuclear applications are absent, although empirical relationships exist in the literature. Here, a hierarchical multiscale modeling approach was presented to address this challenge. This modular approach addressed this difficulty by dividing the various aspects of the composite material into separate models at different length scales, with the evaluated property from the lower-length-scale model serving as an input to the higher-length-scale model. The multiscale model considered the properties of various individual constituents of the composite material (fiber, matrix, and interphase), the porosity in the matrix, the fiber volume fraction, the composite architecture, the tow thickness, etc. By considering inhomogeneous and anisotropic contributions intrinsically, our bottom-up multiscale modeling strategy is naturally physics-informed, bridging constitutive law from micromechanics to meso-mechanics and structural mechanics. The effects that these various physical attributes and thermo-physical properties have on the composite's bulk thermal properties were easily evaluated and demonstrated through the various analyses presented herein. Since silicon carbide fiber-reinforced SiC CMCs are also promising thermal–structural materials with a broad range of high-end technology applications beyond nuclear applications, we envision that the multiscale modeling method we present here may prove helpful in future efforts to develop and construct reinforced CMCs and other advanced composite nuclear materials, such as MAX phase materials, that can service under harsh environments of ultrahigh temperatures, oxidation, corrosion, and/or irradiation. [ABSTRACT FROM AUTHOR]

Compared with the transverse isotropic (TI) medium, the orthorhombic anisotropic medium has both horizontal and vertical symmetry axes and it can be approximated as a set of vertical fissures developed in a group of horizontal strata. Although the full-elastic orthorhombic anisotropic wave equation can accurately simulate seismic wave propagation in the underground media, a huge computational cost is required in seismic modeling, migration, and inversion. The conventional coupled pseudo-acoustic wave equations based on acoustic approximation can be used to significantly reduce the cost of calculation. However, these equations usually suffer from unwanted shear wave artifacts during wave propagation, and the presence of these artifacts can significantly degrade the imaging quality. To solve these problems, we derived a new pure P-wave equation for orthorhombic media that eliminates shear wave artifacts while compromising computational efficiency and accuracy. In addition, the derived equation involves pseudo-differential operators and it must be solved by 3D FFT algorithms. In order to reduce the number of 3D FFT, we utilized the finite difference and pseudo-spectral methods to conduct 3D forward modeling. Furthermore, we simplified the equation by using elliptic approximation and implemented 3D reverse-time migration (RTM). Forward modeling tests on several homogeneous and heterogeneous models confirm that the accuracy of the new equation is better than that of conventional methods. 3D RTM imaging tests on three-layer and SEG/EAGE 3D salt models confirm that the ORT media have better imaging quality. [ABSTRACT FROM AUTHOR]

The cubic phase of Magnesium oxide (MgO) nanoparticles is synthesized by the sol-gel method. The nanoparticles were subjected to annealing at 500∘C to enable stress and strain analysis. Characterization of the annealed nanoparticles was performed using powder X-ray diffraction (XRD). Through analysis of the XRD peak profile, key properties, such as crystallite size, lattice strain, deformation stress, and deformation energy density, were determined. These parameters were estimated using three models such as the Williamson–Hall-Isotropic Strain Model (W-H-ISM), the Williamson–Hall-Anisotropic Strain Model (W-H-ASM), and the Williamson–Hall-Energy Density Model (W-H-EDM). The estimations were based on the W-H plot derived from the powder XRD data. The findings of this study contribute to a better understanding of the structural and mechanical characteristics of annealed MgO nanoparticles, thus informing their potential applications. [ABSTRACT FROM AUTHOR]

Crown ether is widely used in water purification because of its ring structure and good selective adsorption of specific heavy metals. However, its high cost and difficulty in recycling limit the purification of heavy metals in water. The anisotropic [2,4]-dibenzo-18-crown-6-modified bamboo pulp aerogel (DB18C6/PA) is successfully synthesized by microwave irradiation and directional freezing technology. The physical and chemical properties of DB18C6/PA are analyzed by FTIR, XPS, SEM, TEM, TGA, surface area and porosity analyzers. Single or multivariate systems containing Pb2+, Cu2+ and Cd2+ are used as adsorbents. The effects of the DB18C6 addition amount, pH, initial concentration and adsorption temperature on the adsorption of DB18C6/PA are systematically explored. Pseudo-first-order kinetic models, pseudo-second-order kinetic models and the isothermal adsorption models of Langmuir and Freundlich are used to fit the experimental data. The adsorption selectivity is analyzed from the distribution coefficient and the separation factor, and the adsorption mechanism is discussed. The results show that anisotropic DB18C6/PA has the characteristics of 3D directional channels, high porosity (97.67%), large specific surface area (103.7 m2/g), good thermal stability and regeneration (the number of cycles is greater than 5). The surface has a variety of functional groups, including a hydroxyl group, aldehyde group, ether bond, etc. In the single and multivariate systems of Pb2+, Cu2+ and Cd2+, the adsorption process of DB18C6/PA conforms to the pseudo-second-order kinetic model, and the results conform to the Freundlich adsorption isothermal model (a few of them conformed to the Langmuir adsorption isothermal model), indicating that chemical adsorption and physical adsorption are involved in the adsorption process, and the adsorption process is a spontaneous endothermic process. In the single solution system, the maximum adsorption capacities of Pb2+, Cu2+ and Cd2+ by DB18C6/PA are 129.15, 29.85 and 27.89 mg/g, respectively. The adsorption selectivity of DB18C6/PA on Pb2+, Cu2+ and Cd2+ is in the order of Pb2+ >> Cu2+ > Cd2+. [ABSTRACT FROM AUTHOR]

The negative impact of heavy metal pollution, specifically chromium (VI), on human health is well‐documented. To solve this issue, hollow anisotropic hierarchically porous "Fish Cage"‐like carbonaceous nanomaterial (N,S‐HFC‐180) with multi‐active groups is synthesized. Hierarchically porous structure provides stepped adsorption effect. The addition of K2C2O4 leads to an increase in the specific surface area of N,S‐HFC‐180 to 1914.21 m2 g−1 (an increase of ~552 times compared to HFC‐180). Thiourea introduces multi‐active groups that act as "Barbs" in "Fish Cage", further reducing Cr(VI) to Cr(III) and sequestrating Cr(III) by coordination effect. Subsequent batch studies suggest that N,S‐HFC‐180 exhibits a high removal capacity of 164.29 mg g−1 for Cr(VI) at pH=2. The kinetics and isotherm analyses display an outstanding maximum adsorption capacity of 393.88 mg g−1 at 298 K. In addition, even after seven cycles, the removal rate of Cr(VI) using N,S‐HFC‐180 remains>85.00 %, and it effectively reduces the concentration of electroplating wastewater from 55.82 to 0.14 mg L−1. Pore filling, chemical reduction and chelation, hydrogen bond and electrostatic attraction are the primary adsorption drivers. The results suggest that, the recoverable N,S‐HFC‐180 highlights its viability for practical applications in wastewater treatment processes. [ABSTRACT FROM AUTHOR]

Hydrogels hold great promise in the field of flexible electronics. Attempts in this area tend to the microstructure design of hydrogels, giving them specific adhesion and multi‐sensing functions. Here, a novel phase separation‐derived anisotropic adhesive structural color hydrogel film is presented for visually flexible electronics. The hydrogel film is generated by template replicating colloidal crystal by using phase separation emulsions of hydrophilic monomer (acrylic acid, AA), hydrophobic monomer (lauryl methacrylate, LMA), co‐monomer ([2‐(methacryloyloxy) ethyl] dimethyl‐(3‐sulfopropyl) ammonium hydroxide (SBMA)), surfactants (hexadecyl trimethyl ammonium bromide, CTAB) and initiator (ammonium persulphate (APS)). The appearance of phase separation results in asymmetric morphologies of hydrogel film, imparting them with anisotropic adhesive performance. Attributed to the formation of inverse opal scaffold structure, the hydrogel film is featured with vivid structural color, showing superior capability in self‐reporting mechanical behavior. Additionally, benefitting from the presence of abundant ions, the hydrogel film exhibits great conductivity. Thus, the resultant hydrogel film is demonstrated with stable dual‐signal sensing properties involving color‐changing and conductivity feedback ability to respond to human activities. These features make the proposed anisotropic adhesive structural color hydrogel film highly potential in the flexible electronic field. [ABSTRACT FROM AUTHOR]

Conventional research on linear polarization photodetector for 2D materials has focused on the search for different anisotropic materials, combinations between materials, introducing plasmonic structures, and patterning 2D materials to improve performance. However, these methods provide limited improvement in polarization sensitivity. Here, a balanced photodetector structure is proposed that does not require an additional process and relies only on the presence of anisotropy in the material itself to substantially improve the polarization sensitivity. The balanced photodetector consists of two ReS2 photodetectors, where the single ReS2 photodetector exhibits excellent performance at 650 nm illumination, including a responsivity and detectivity of 0.28 A W−1 and 4.22 × 109 Jones. Benefiting from the anisotropy of ReS2, the single photodetector achieves excellent polarization sensitivity of 2.79 at 650 nm. The balanced photodetector system achieves an excellent performance of ≈20 dB linear polarization extinction ratio and 0.003° Hz−1/2 noise equivalent light polarization difference at 100 kHz. These performances can also be further optimized by adjusting the gate voltage. The results provide a basis for further development of high‐performance polarization photodetector for 2D materials. [ABSTRACT FROM AUTHOR]

A medium is isotropic if its elastic properties do not change with direction. The usual meaning of seismic anisotropy is variation of seismic velocity, which itself depends on the elastic properties of the medium, with the direction in which it is measured. In sedimentary rock sequences, the anisotropy may be caused by preferred orientation of anisotropic mineral grains, preferred orientation of cracks or thin bedding of layers. Anisotropy parameters that defined by Thomsen are ε and δ. Thomsen’s anisotropic parameters are estimated by well and seismic data. However, one difficulty in addressing anisotropy lies not in the algorithms, but in the reliable estimation of anisotropic parameters. Most of seismic data analysis assume isotropic behavior for subsurface while the earth is often anisotropic and seismic velocity isn’t constant in different directions. So, this analysis must consider anisotropic assumption. One of the most common anisotropy-related phenomena is seismic imaging. Output of migration is the section that is similar to the geological model. Depth migration leads to correct image when velocity changes laterally and vertically in the subsurface. Generally, isotropic Pre-Stack Depth Migration (PSDM) corrects only for lateral velocity heterogeneity; however, anisotropic PSDM algorithms also correct for velocity changing with direction. Anisotropic PSDM corrects for vertical shifts, correctly positions events in depth, and properly focuses diffraction energy. Thomsen’s anisotropic parameters, ε and δ, are two main parameters required in a velocity model for PSDM imaging. Accurate estimation of travel time is very essential in seismic imaging and velocity analysis. Inaccurate approximation of travel time leads to migration errors. Several equations have been developed for nonhyperbolic travel time approximation in transversely isotropic media with vertical symmetry axis (vertical transverse isotropy, VTI). In this study, 2D seismic line and well data are used for doing isotropic and anisotropic PSDM. Conventional processing sequences are performed on seismic data. Initial velocity model was created and then 3 horizons were picked on seismic section. Anisotropy parameters are calculated using true depth of horizons in seismic and well data and then PSDM is performed with and without considering anisotropic parameters. Results of applying anisotropic PSDM in seismic data show that this method moves the events to correct positions and can significantly reduce seismic-to-well mis ties, hence, providing more accurate structural images in depth domain. In addition, anisotropic PSDM attenuates the hockey stick events on CDP gathers and so improves reflector continuity in the subsurface image especially in shallow parts. [ABSTRACT FROM AUTHOR]

Conventional research on linear polarization photodetector for 2D materials has focused on the search for different anisotropic materials, combinations between materials, introducing plasmonic structures, and patterning 2D materials to improve performance. However, these methods provide limited improvement in polarization sensitivity. Here, a balanced photodetector structure is proposed that does not require an additional process and relies only on the presence of anisotropy in the material itself to substantially improve the polarization sensitivity. The balanced photodetector consists of two ReS2 photodetectors, where the single ReS2 photodetector exhibits excellent performance at 650 nm illumination, including a responsivity and detectivity of 0.28 A W−1 and 4.22 × 109 Jones. Benefiting from the anisotropy of ReS2, the single photodetector achieves excellent polarization sensitivity of 2.79 at 650 nm. The balanced photodetector system achieves an excellent performance of ≈20 dB linear polarization extinction ratio and 0.003° Hz−1/2 noise equivalent light polarization difference at 100 kHz. These performances can also be further optimized by adjusting the gate voltage. The results provide a basis for further development of high‐performance polarization photodetector for 2D materials. [ABSTRACT FROM AUTHOR]

ABSTRACT The developed laminar structure of shale makes it possess obvious anisotropic characteristics, and these anisotropic characteristics are one of the important factors leading to the strong and weak heterogeneous properties of shale. Additionally, there is a common phenomenon where the propagation of hydraulic fracture heights is limited in the hydraulic fracturing process of strongly heterogeneous shale reservoirs. To clarify the reasons for the limited height propagation of hydraulic fractures in strongly heterogeneous shale reservoirs, numerical simulation methods were used to study the propagation patterns of hydraulic fractures in shale reservoirs under different levels of anisotropy, flow rate, viscosity, and stress differences. The results show that as the anisotropy value increases and the heterogeneity becomes stronger, it becomes more difficult for hydraulic fractures to expand along the fracture height direction, and the fracture width at the fracture opening becomes larger. For strongly heterogeneous shale reservoir, the hydraulic fracture height can be increased within a certain range by increasing the flow rate, viscosity, and stress difference. When the upper limit value is exceeded, the hydraulic fracture height of the strong heterogeneous shale reservoir gradually becomes stable, and the increasing trend is no longer obvious. The strong or weak heterogeneity caused by the inherent anisotropic characteristics of shale reservoirs affects the development and transformation effectiveness of shale reservoirs. The research in this article will provide some reference material and guidance for the efficient development of shale reservoirs.

Advances in the study of structural ceramic materials have revealed new perspectives and opportunities, with an increasing emphasis on incorporating biomimicry concepts. Carbide ceramics with anisotropic crystal structures—such as silicon carbide—exhibit superior properties, including high modulus, high-temperature resistance, wear resistance, and high thermal conductivity, making them ideal structural materials. The implementation of biomimetic texturing techniques can enhance their performance along specific orientations, thereby expanding their potential for use in more rigorous environments and endowing them with integrated structural and functional characteristics. This review provides an overview of commonly textured biological materials and discusses their performance. It emphasizes the techniques used to prepare anisotropic carbide ceramics and anisotropic carbide ceramic composites—such as strong external field induction (hot working under uniaxial pressure, casting technologies within magnetic alignment, etc.), template methods (biotemplating, ice templating, etc.), and three-dimensional printing technologies (direct ink writing, stereolithography, etc.)—focusing on the work of researchers within the structural ceramic community, summarizing the current challenges in the preparation of anisotropic carbide ceramic composites, and providing insight into their future development and application.

The area-preserving flow and the length-preserving flow with the power of anisotropic curvature as their velocity are studied in this paper. For embedded convex closed initial curves, both of the area-preserving flow and the length-preserving flow are shown to exist globally and converge smoothly to the boundary of the homothety of Wulff shape, which is determined by corresponding anisotropic function. [ABSTRACT FROM AUTHOR]

This paper addresses a significant research gap in the study of surface waves propagation in a nonhomogeneous, within a magneto-thermoviscoelastic material of higher order, initial stress, rotation, gravity effects and voids. This study provides analytical solutions for surface waves propagating through a medium consisting of a magneto-thermoelastic material with voids under the rotation, electro-magnetic field, gravity field and initial stress. The analytical solutions are derived for the displacement components, volume fraction, temperature to Stoneley and Rayleigh waves are computed numerically and presented graphically considering the external parameters impact. Furthermore, this investigates how magnetic field, voids, gravity, initial stress and fiber-reinforced parameters influence these wave phenomena. This investigation provides valuable insights into the synergistic dynamics among electric constituents, voids, Stoneley and Rayleigh waves propagation, enabling advancements in sensor technology, augmented energy harvesting methodologies, and pioneering seismic monitoring approaches. For certain materials, numerical simulations are provided and graphically displayed. The results of this study reveal several unique cases that significantly contribute to the understanding of Rayleigh and Stoneley waves propagation within this intricate material system, particularly in the presence of voids.

Highlights A novel anisotropic sensor with oriented piezoelectric filaments was prepared, capable of detecting both the magnitude and direction of micro-deformations. Due to the efficient load transfer of continuous fibers and the formation of porous ferroelectrets, an ultra-low strain detection limit of 0.06% was achieved in the sensor. Given the sensor's ultra-low detection limit and deformation direction sensing capability, we developed the sensor for detecting micron-scale deformations in thin-film structures and for robotic tactile sensing applications.

Creep behavior is a very important attribute of shale and is crucial in the design of hydraulic fracturing schemes to ensure the long-term stable development of shale gas. However, how different shale minerals, organic matter, bedding planes, and pores affect the micro-creep behavior of Upper Ordovician Wufeng and Lower Silurian Longmaxi (WF–LMX) Formation shales is poorly understood. In this study, we employed a nanoindentation mechanical testing technique alongside rock mineralogical, major elemental, and pore analyses to investigate the creep behavior and influencing factors of WF–LMX shales at the microscale. The results show that (1) the creep displacement (Δh) and indentation creep parameter (CIT) are each positively correlated with clay, total pore volume, and clay + total organic carbon (TOC) contents but negatively correlated with the content of quartz, excess SiO2, and TOC. We found weak or no correlation between the occurrence of minor rock constituents, such as feldspar, carbonates, and pyrite, and the shale creep properties; (2) the creep parameters (Δh, CIT, and stress exponent (n)) exhibit anisotropy due to the layering of shale, with values 7.3%–24.2% higher in the plane perpendicular to bedding (X1) than those in the plane parallel to bedding (X3). The creep displacement exhibits negative correlations with Young's modulus, hardness, and stress exponent (n), especially for the X1 direction; (3) compared with those of China's Yanchang shale, the stress exponents of WF–LMX shale are relatively high (8.5–30), indicating that the average creep capacity of WF–LMX shale is relatively weak. Overall, nanoindentation technology has shown great potential in studying shale creep and provides quantitative data support for macroscopic shale creep research.

In order to determine the influence of anisotropy induced by primary bedding structure on fracture toughness and fracture process zone (FPZ) incubation characteristics of anthracite, the notched semi-circular bending (NSCB) anthracite samples with different bedding angles were subjected to the mode I three-point bending loading test on the MTS hydraulic servo test system. The incubation process of FPZ at crack tip was monitored by the digital image correlation method (DICM) combined with the acoustic emission (AE) localization technique. Based on the Irwin-Bazant model, the Strip-yield uniform traction model and the Strip-yield linear traction model, the fully developed FPZ length of anthracite samples were predicted and compared with the experimental results. The geometric morphology of anisotropic anthracite FPZ and the shear and tensile deformation time series of anthracite FPZ during its incubation at different bedding angles were discussed. The results show that the peak load, peak displacement and fracture toughness of anthracite increase with the increase of bedding inclination. Compared with the coal samples with the bedding angle of 0°, the average fracture toughness of the coal samples with the bedding angle of 22.5°, 45.0°, 67.5° and 90.0° increases by 6.76%, 86.82%, 85.47% and 134.46%, respectively. The FPZ length predicted by the Irwin-Bazant model and the Strip-yield uniform traction model is shorter than the test value, while the prediction of the Strip-yield linear traction model is generally higher than the test value. The estimation of FPZ length of anthracite by the Strip-yield uniform traction model is most close to the experimental value, indicating that the distribution of the cohesive force at the crack tip of the anthracite sample tends to be more uniform. The FPZ length of anthracite sample is proportional to the square of the ratio of fracture toughness and tensile strength: L∝(KIC/σt)2. The prefabricated crack tip deformation of the sample is dominated by tensile deformation and assisted by shear. The tensile deformation ranges from 27.71% to 57.26% Pmax, and the shear deformation ranges from 72.88% to 92.4% Pmax. The time of tensile deformation of the crack tip is superior to that of shear deformation. The strain field distribution on the circumferential measuring lines of the samples with the bedding angle of 0° and 45° is similar to the texture distribution of onion cross section, while the maximum principal strain monitoring value of the samples with the bedding angle of 90° shows a fluctuation and disordered distribution at most measuring angles. The strain gradient of anthracite sample is different on the divergence line of FPZ tip in each direction.

Nanocatalytic therapeutic agents with triple synergistic treatment modes of chemodynamic therapy (CDT), photothermal therapy (PTT) and photodynamic therapy (PDT) are emerging nanomaterials in malignancy treatment. Nevertheless, the passive diffusion and transport of nanomaterials result in poor permeability in tumor lesions, severely affecting the effectiveness of synergistic therapy. Herein, a dual‐source‐driven parachute‐like Au2Pt@PMO@ICG Janus nanomotor (APIJNS) is prepared by an interfacial energy‐mediated anisotropic growth strategy for PTT‐mediated CDT/PDT triple synergistic cancer therapy. Such nanomotor can realize self‐thermophoresis drive under the trigger of near‐infrared light, which can effectively enhance the active permeability and uptake of the APIJNS in the tumor tissue, thus achieving efficient PTT/PDT/CDT synergistic therapeutic effect. In addition, parachute‐like APIJNS exhibits high‐efficiency catalase (CAT)‐like activity and can catalyze the overexpressed H2O2 in the tumor microenvironment (TME) to generate oxygen (O2), not only alleviating the hypoxia in the tumor lesion, but also converting it into singlet oxygen (1O2) to activate the photosensitizer ICG, achieving PDT. This work provides new ideas for enhancing triple synergistic cancer therapy by improving tumor permeability with dual‐drive Janus nanomotors based on dual noble metal nanozymes. [ABSTRACT FROM AUTHOR]

This paper addresses a significant research gap in the study of surface waves propagation in a nonhomogeneous, within a magneto-thermoviscoelastic material of higher order, initial stress, rotation, gravity effects and voids. This study provides analytical solutions for surface waves propagating through a medium consisting of a magneto-thermoelastic material with voids under the rotation, electro-magnetic field, gravity field and initial stress. The analytical solutions are derived for the displacement components, volume fraction, temperature to Stoneley and Rayleigh waves are computed numerically and presented graphically considering the external parameters impact. Furthermore, this investigates how magnetic field, voids, gravity, initial stress and fiber-reinforced parameters influence these wave phenomena. This investigation provides valuable insights into the synergistic dynamics among electric constituents, voids, Stoneley and Rayleigh waves propagation, enabling advancements in sensor technology, augmented energy harvesting methodologies, and pioneering seismic monitoring approaches. For certain materials, numerical simulations are provided and graphically displayed. The results of this study reveal several unique cases that significantly contribute to the understanding of Rayleigh and Stoneley waves propagation within this intricate material system, particularly in the presence of voids. [ABSTRACT FROM AUTHOR]

Highlights: A novel anisotropic sensor with oriented piezoelectric filaments was prepared, capable of detecting both the magnitude and direction of micro-deformations. Due to the efficient load transfer of continuous fibers and the formation of porous ferroelectrets, an ultra-low strain detection limit of 0.06% was achieved in the sensor. Given the sensor's ultra-low detection limit and deformation direction sensing capability, we developed the sensor for detecting micron-scale deformations in thin-film structures and for robotic tactile sensing applications. Monitoring minuscule mechanical signals, both in magnitude and direction, is imperative in many application scenarios, e.g., structural health monitoring and robotic sensing systems. However, the piezoelectric sensor struggles to satisfy the requirements for directional recognition due to the limited piezoelectric coefficient matrix, and achieving sensitivity for detecting micrometer-scale deformations is also challenging. Herein, we develop a vector sensor composed of lead zirconate titanate-electronic grade glass fiber composite filaments with oriented arrangement, capable of detecting minute anisotropic deformations. The as-prepared vector sensor can identify the deformation directions even when subjected to an unprecedented nominal strain of 0.06%, thereby enabling its utility in accurately discerning the 5 μm-height wrinkles in thin films and in monitoring human pulse waves. The ultra-high sensitivity is attributed to the formation of porous ferroelectret and the efficient load transfer efficiency of continuous lead zirconate titanate phase. Additionally, when integrated with machine learning techniques, the sensor's capability to recognize multi-signals enables it to differentiate between 10 types of fine textures with 100% accuracy. The structural design in piezoelectric devices enables a more comprehensive perception of mechanical stimuli, offering a novel perspective for enhancing recognition accuracy. [ABSTRACT FROM AUTHOR]

This paper investigates the stability problem and large time behavior of solutions to the three‐dimensional magnetohydrodynamic equations with horizontal velocity dissipation and magnetic diffusion only in the x2$x_2$ direction. By applying the structure of the system, time‐weighted methods, and the method of bootstrapping argument, we prove that any perturbation near the background magnetic field (1, 0, 0) is globally stable in the Sobolev space H3(R3)$H^3(\mathbb {R}^3)$. Furthermore, explicit decay rates in H2(R3)$H^2(\mathbb {R}^3)$ are obtained. Motivated by the stability of the three‐dimensional Navier–Stokes equations with horizontal dissipation, this paper aims to understand the stability of perturbations near a magnetic background field and reveal the mechanism of how the magnetic field generates enhanced dissipation and helps stabilize the fluid. [ABSTRACT FROM AUTHOR]

Screen-space ambient occlusion (AO) is a popular global illumination technique which can be used to achieve a better understanding of complex 3D streamtubes scenes. This paper proposed an anisotropic screen-space AO method to visualize complex 3D streamtubes. The basic idea is to utilize the characteristics of 3D streamtubes to design two anisotropic filters to guide screen-space sampling as well as spatial reusing. More specifically, this paper proposed to anisotropically generate samples perpendicular to the direction of streamtube to calculate AO. This mechanism can reduce the number of samples required to generate satisfactory results. In order to further improve the performance of the algorithm, this paper proposed to anisotropically reuse AO results from nearby pixels along the streamtube direction. The experimental results indicate that the proposed algorithm outperforms the existing solutions both in rendering quality and performance. [ABSTRACT FROM AUTHOR]

An analysis of the propagation behavior of Rayleigh wave has been conducted in an anisotropic layer, such as reservoir rocks overlying a sandy medium. The layer and lower half-space interface have been considered imperfect, whereas a corrugated upper boundary has been assumed. A closed relation of phase velocity and wave number has been obtained as a determinant form. For the numerical interpretation of results, reservoir rocks of triclinic type have been modeled. Some special cases are taken into account. The study examines the simultaneous simulated results of several physical parameters and illustrates the effects of thickness, sandiness parameter, phase velocity, corrugation amplitude, corrugation wavelength, and imperfect Rayleigh wave interface distribution in the structure under consideration, which was created using Mathematica 7. For variations in wave number and phase velocity, diagrams are drawn. [ABSTRACT FROM AUTHOR]

AniMAIRE (Anisotropic Model for Atmospheric Ionising Radiation Effects) is a new model and Python toolkit for calculating radiation dose rates experienced by aircraft during anisotropic solar energetic particle events. AniMAIRE expands the physics of the MAIRE + model such that dose rate calculations can be performed for anisotropic solar energetic particle conditions by supplying a proton or alpha particle rigidity spectrum, a pitch angle distribution, and the conditions of Earth's magnetosphere. In this paper, we describe the algorithm and top‐level structure of AniMAIRE and showcase AniMAIRE's capabilities by analyzing the dose rate maps that AniMAIRE produces when the time‐dependent spectra and pitch angle distribution for Ground Level Enhancement (GLE) 71 are input. We find that the dose rates AniMAIRE produces for the event fall between the dose rates produced by the WASAVIES and CRAC:DOMO models. Dose rate maps that evolve throughout the event are also shown, and it is found that each peak in the input pitch angle distribution generates a dose rate hotspot in each of the polar regions. AniMAIRE has been made available openly online so that it can be downloaded and run freely on local machines and so that the space weather community can easily contribute to it using Github forking. Plain Language Summary: Solar particle events occur when particles are accelerated in eruptions on the Sun. If these particles hit Earth and have enough energy, they can penetrate Earth's magnetosphere and atmosphere, creating radiation showers that increase the radiation in Earth's atmosphere. When such increases are detected by neutron monitors at sea level, they are known as Ground‐Level Enhancements (GLEs), which occur once a year on average. GLEs can cause issues in aircraft electronics and cause passengers and crew on airplanes to experience heightened radiation doses. In this paper, we describe a new model to calculate radiation dose rates in the atmosphere during GLEs, called AniMAIRE. Most models that exist to date are only able to calculate radiation dose rates when all particles are hitting Earth equally from all directions, however this approximation is only reliable during the later stages of events, and isn't accurate for many GLEs. AniMAIRE has been designed so it doesn't need to rely on this approximation, and can calculate dose rates for situations where it is supplied a direction‐dependent particle flux, as well as those independent of direction. AniMAIRE has been tested across a GLE in May 2012, showing the direction dependent approach is necessary. Key Points: AniMAIRE can simulate atmospheric radiation and electronics effects from anyinput anisotropic distribution of particles hitting EarthAnisotropy is important in the event‐integrated dose calculation for GLE71 according to AniMAIREAniMAIRE has been made openly available online, such that anyone can run and experiment with it, or contribute to the model through forking [ABSTRACT FROM AUTHOR]

In order to enhance the reliability and accuracy of the results from the transient plane source (TPS) method for measuring the thermal conductivity of wood, this paper investigates setting parameters and measurement methods to improve measurement accuracy. Criteria are proposed to determine the optimal parameters such as the power output, heating time, and time window. The measurement results of the TPS method and the HFM method are compared. The results show that the total to characteristic time, temperature increase in the probe, mean deviation, and temperature drift graph are valid indicators for evaluating the detection reliability of the TPS method. The optimal parameters for measuring the thermal conductivity of wood using the TPS method are as follows: power output of 0.05 or 0.1 W, heating time of 120 s, and time window covering 60% to 80% of the heating time. The thermal conductivity measured with the TPS method was higher than that measured by the steady-state method in all grain angle directions. The standard uncertainties after optimization were 18.9% to 59.5% lower than before optimization. The optimized TPS measurement method can be applied to other tree species as well. [ABSTRACT FROM AUTHOR]