Photoacoustic imaging,an acoustic imaging modality with potentially optical resolution in an optical turbid medium,has attracted great ***,the convergence of wavefront optimization and raster scanning in computational...
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Photoacoustic imaging,an acoustic imaging modality with potentially optical resolution in an optical turbid medium,has attracted great ***,the convergence of wavefront optimization and raster scanning in computational photoacoustic imaging leads to the challenge of fast mapping,especially for a spatial resolution approaching the acoustic deep-subwavelength *** a sparse sampling paradigm,compressive sensing has been applied in numerous fields to accelerate data acquisition without significant quality *** this work,we propose a dual-compressed approach for photoacoustic surface tomography that enables high-efficiency imaging with 3D spatial resolution unlimited by the acoustics in a turbid *** dual-compressed photoacoustic imaging with single-pixel detection,enabled by spatially optical modulation with synchronized temporally photoacoustic coding,allows decoding of the fine optical information from the modulated acoustic signal even when the variance of original photoacoustic signals is *** perform a proof-of-principle numerical demonstration of dual-compressed photoacoustic imaging, that resolves acoustic sub-acoustic-wavelength details with a significantly reduced number of measurements,revealing the potential for dynamic *** dual-compressed concept,which transforms unobtrusive spatial difference into spatio-temporal detectable information,can be generalized to other imaging modalities to re alize efficient,high-spatial-resolution imaging.
The memory effect in a single-crystal spin glass (Cu0.92Mn0.08) has been measured using 1 Hz ac susceptibility techniques over a temperature range of 0.4–0.7Tg, and a model of the memory effect has been developed. A ...
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The memory effect in a single-crystal spin glass (Cu0.92Mn0.08) has been measured using 1 Hz ac susceptibility techniques over a temperature range of 0.4–0.7Tg, and a model of the memory effect has been developed. A double-waiting-time protocol is carried out where the spin glass is first allowed to age at a temperature below Tg, followed by a second aging at a lower temperature, Tw2, after it has fully rejuvenated. The model is based on calculating typical coincident growth of correlated regions at the two temperatures. It accounts for the absolute magnitude of the memory effect as a function of both waiting times and temperatures. The data can be explained by the memory loss being a function of the relative change in the correlated volume at the first waiting temperature because of the growth in the correlations at the second waiting temperature.
Ceramic materials with intricate structures can be efficiently fabricated using stereolithography(SLA)based 3D printing technology,offering advantages over traditional *** temperature has primary effect on properties ...
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Ceramic materials with intricate structures can be efficiently fabricated using stereolithography(SLA)based 3D printing technology,offering advantages over traditional *** temperature has primary effect on properties of *** study investigated the crucial sintering temperature for 3D printed ceramics to ensure the desired *** results indicate that all samples exhibit a consistent layered structure across the experimental sintering *** the sintering temperature is increased from 1,250℃ to 1,350℃,the grain's morphology changes from spherical to *** morphology analysis reveals a decrease in surface roughness at sintering temperatures above 1,350℃.Mechanical tests show improved flexural strength and stiffness as the sintering temperature *** and wear experiments demonstrate that as the sintering temperature increases from 1,450℃ to 1,550℃,the wear pattern on ceramic surfaces transitions from deep pits to shallow *** increase in sintering temperature effectively enhances the wear resistance of 3D printed alumina *** improvement plays a significant role in expanding the application field of these ceramics,prolonging the lifespan of parts,reducing production costs,enhancing performance,and promoting environmental *** this study,ceramics achieve the highest strength and best wear resistance when sintered at 1,600℃,resulting in the best overall performance.
The search for heavy elements has yielded many surprises and enhanced our knowledge of nuclear synthesis and associated dynamical *** new elements and their associated isotopes have been synthesized,information concer...
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The search for heavy elements has yielded many surprises and enhanced our knowledge of nuclear synthesis and associated dynamical *** new elements and their associated isotopes have been synthesized,information concerning elements with Z≥102,remains ***,concerning the transfermium elements,the nuclear shell structure is key to ensuring nuclear ***,the shell effects have key implications on such *** experimental and theoretical investigations have been conducted to examine the reactions induced by heavy ions and the subsequent decay mechanisms in the superheavy mass *** addition,the region of transfermium elements is of great interest because of the neutron/proton shell ***,our objective is to analyze the decay mechanisms of nuclides having Z=102 nuclei,i.e.,^(248)No*and^(250)No*.An extensive study was conducted using the dynamical cluster-decay model(DCM)based on Quantum Mechanical Fragmentation Theory(QMFT).The focus was to investigate compound nucleus(CN)and non-compound nucleus(nCN)mechanisms,including fusion-fission(ff),quasi-fission(QF),and fast fission(FF).The specific isotopes of interest are^(248)No*and^(250)No*,with attention given to the role of the center-of-mass energy(E_(c.m))and angular momentum(l).The nuclear interaction potential was derived using the Skyrme energy density formalism(SEDF)with the GSkI force *** capture cross-sections were calculated using the-summed Wong *** determination of the probability of compound nucleus formation(PCN)involved a function that is dependent upon the center-of-mass *** lifetimes of the ff and QF channels were also ***,CN and nCN decay mechanisms for two isotopes of Z=102 nobelium were analyzed over the range of center-of-mass values(E_(c.m))considering the quadrupole deformationβ_(2)and optimum orientations(θ_(opt))of the decaying *** fragmentation potential,preformation probability,neck length parameter,and
This paper presents a systematic investigation of the microstructure and magnetocaloric properties of melt-extracted Sm_(20)Gd_(20)Dy_(20)Co_(20)Al_(20)high-entropy *** fabricated wires exhibited an amorphous structur...
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This paper presents a systematic investigation of the microstructure and magnetocaloric properties of melt-extracted Sm_(20)Gd_(20)Dy_(20)Co_(20)Al_(20)high-entropy *** fabricated wires exhibited an amorphous structure,and the temperature interval of the undercooled liquid AT was 45 *** microwires underwent a second-order magnetic transition from a ferromagnetic to a paramagnetic state near the Curie temperature(T_(C)=52 K),The maximum magnetic entropy change(-ΔS_M^(max)),the relative cooling power and the refrigeration capacity reached 6.34 J·kg^(-1)·K^(-1).422.09 J·kg^(-1)and 332.94 J·kg^(-1),respectively,under a magnetic field change of 5 *** addition,the temperature-averaged entropy changes with two temperature lifts(3 and 10 K)were 6.32 and 6.27 J·kg^(-1)·K^(-1),*** good magnetocalorie performance highlights the significant potential for the Sm_(20)Gd_(20)Dy_(20)Co_(20)Al_(20)microwires to be used as magnetic refrigerant materials in low-temperature region *** work will serve as a valuable reference for future investigations on low-temperature high-entropy magnetocaloric materials.
The magnetic correlations at the superconductor/ferromagnet(S/F) interfaces play a crucial role in realizing dissipation-less spin-based logic and memory technologies,such as triplet-sup ercurrent spin-valves and ...
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The magnetic correlations at the superconductor/ferromagnet(S/F) interfaces play a crucial role in realizing dissipation-less spin-based logic and memory technologies,such as triplet-sup ercurrent spin-valves and 'π'Josephson *** we report the observation of an induced large magnetic moment at high-quality nitride S/F *** polarized neutron reflectometry and DC S QUID measurements,we quantitatively determined the magnetization profile of the S/F bilayer and confirmed that the induced magnetic moment in the adjacent superconductor only exists below ***,the direction of the induced moment in the superconductors was unexpectedly parallel to that in the ferromagnet,which contrasts with earlier findings in S/F heterostructures based on metals or ***-principles calculations verified that the unusual interfacial spin texture observed in our study was caused by the Heisenberg direct exchange coupling with constant J~4.28 meV through d-orbital overlapping and severe charge transfer across the *** work establishes an incisive experimental probe for understanding the magnetic proximity behavior at S/F interfaces and provides a prototype epitaxial 'building block' for superconducting spintronics.
We report on the discovery of a boundary-induced body-centered tetragonal iron phase in thin films deposited on MgAl2O4 (001) substrates. We present evidence for this phase using detailed x-ray analysis and ab initio ...
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We report on the discovery of a boundary-induced body-centered tetragonal iron phase in thin films deposited on MgAl2O4 (001) substrates. We present evidence for this phase using detailed x-ray analysis and ab initio density functional theory calculations. A lower magnetic moment and a rotation of the easy magnetization direction are observed, as compared with body-centered cubic iron. Our findings expand the range of known crystal and magnetic phases of iron, providing valuable insights for the development of heterostructure devices using ultrathin iron layers.
Defects in materials significantly alter their electronic and structural properties,which affect the per-formance of electronic devices,structural alloys,and functional ***,calculating all the possible defects in comp...
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Defects in materials significantly alter their electronic and structural properties,which affect the per-formance of electronic devices,structural alloys,and functional ***,calculating all the possible defects in complex materials with conventional Density Functional Theory(DFT)can be compu-tationally *** enhance the efficiency of these calculations,we interfaced Density Functional Tight Binding(DFTB)with the Clusters Approach to Statistical Mechanics(CASM)software package for the first *** SiC and ZnO as representative examples,we show that DFTB gives accurate results and can be used as an efficient computational approach for calculating and pre-screening formation ener-gies/convex *** DFTB+CASM implementation allows for an efficient exploration(up to an order of magnitude faster than DFT)of formation energies and convex hulls,which researchers can use to probe other complex systems.
The large spin-orbit coupling in iridium oxides plays a significant role in driving novel physical behaviors, including emergent phenomena in the films and heterostructures of perovskite and Ruddlesden-Popper iridates...
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The large spin-orbit coupling in iridium oxides plays a significant role in driving novel physical behaviors, including emergent phenomena in the films and heterostructures of perovskite and Ruddlesden-Popper iridates. In this Letter, we study the role of epitaxial strain on the electronic behavior of thin SrIrO3 films. We find that compressive epitaxial strain leads to metallic transport behavior, but a slight tensile strain shows gapped behavior. Temperature-dependent resistivity measurements are used to examine different behaviors in films as a function of strain. We find Kondo contributions to the resistivity, with stronger effects in films that are thinner and under less compressive epitaxial strain. These results show the potential to tune SrIrO3 into Kondo insulating states and open possibilities for a quantum critical point that can be controlled with strain in epitaxial films.
It is generally considered that heat treatments have a negative impact on the mechanical properties of nacre due to thermal decomposition of the organic ***,the present work investigated the microindentation behavior ...
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It is generally considered that heat treatments have a negative impact on the mechanical properties of nacre due to thermal decomposition of the organic ***,the present work investigated the microindentation behavior on fresh and heat-treated nacres from two orthogonal directions,and the results demonstrate that both hardness value and damage tolerance can remain almost unchanged on the cross-section with the organic matrix degeneration,despite a significant deterioration on the platelet *** analyses suggest that the anisotropic response of indentation behavior to heat treatment in nacre is primarily caused by its structural ***,compared with a single layer of irregular interplatelet interfaces in cross-sectional specimens,the multiple layers of parallel interlamellar interfaces in in-plane specimens exhibit a much greater ability to impede indenter-triggered destruction,and heat treatments would reduce the in-plane hardness but nearly have no effect on the cross-sectional ***,the deeper embedding of platelets in cross-sectional specimens enhances their resistance to interface cracking caused by organic matrix degradation at high temperatures,leading to a reduced sensitivity to ***,the indentation behavior of nacre shows different tendencies in response to variations in the organic matrix state along normal and parallel directions.
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