The inverse Faraday effect is an optomagnetic phenomenon that describes the ability of circularly polarized light to induce magnetism in solids. The capability of light to control magnetic order in solid state materia...
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The inverse Faraday effect is an optomagnetic phenomenon that describes the ability of circularly polarized light to induce magnetism in solids. The capability of light to control magnetic order in solid state materials and devices is of interest for a variety of applications, such as magnetic recording, quantum computation, and spintronic technologies. However, significant gaps in understanding about the effect persist, such as what material properties govern the magnitude of the effect in metals. In this work, we report time-resolved measurements of the specular inverse Faraday effect in nonmagnetic metals, i.e., the magneto-optic Kerr effect induced by circularly polarized light. We measure this specular inverse Faraday effect in Cu, Pd, Pt, W, Ta, and Au at a laser wavelength of 783 nm. For Ta and W, we investigate both α and β phases. We observe that excitation of these metals with circularly polarized light induces significant circular dichroism. This nonlinear magneto-optical response to circularly polarized light is an order of magnitude larger in α-W than other metals, e.g., Pt or Au, and is greater than nearly all other reported values for the inverse Faraday effect in other materials. Our results benchmark the range of the inverse Faraday effect that can be observed in nonmagnetic metals and provide insight into what material properties govern the inverse Faraday effect in metals.
Molecular self-assembly is a natured-inspired strategy to integrate individual functional molecules into supramolecular nanostructured materials through noncovalent bond interactions for solar to fuel ***,the design a...
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Molecular self-assembly is a natured-inspired strategy to integrate individual functional molecules into supramolecular nanostructured materials through noncovalent bond interactions for solar to fuel ***,the design and engineering of the morphology,size,and orderly stacking of supramolecular nanostructures remain a great *** this study,regular porphyrin nanocrystals with different orderly stacked structures are synthesized through noncovalent self-assembly of Pt(II)meso-tetra(4-carboxyphenyl)porphine(PtTCPP),using surfactants with different *** synergy of noncovalent bond interactions between porphyrin molecules,and between porphyrin molecules and surfactants resulted in different molecular packing *** to the spatial ordering of PtTCPP molecules,the different nanocrystals exhibit both collective optical properties and morphology-dependent activities in photocatalytic hydrogen *** measurements of the photodeposition of dual cocatalysts showed that the photogenerated electrons and holes selectively aggregated at different active sites,revealing separation pathways and directional transfer of photogenerated electrons and holes in the *** study provides a new strategy to exert rational control over porphyrin self-assembly nanocrystals for highly efficient water splitting.
Many wearable soft robotic devices have been developed to assist with spasticity – the increased muscle tone seen in individuals with neurological conditions such as stroke or cerebral palsy. However, these devices t...
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ISBN:
(数字)9798331520205
ISBN:
(纸本)9798331520212
Many wearable soft robotic devices have been developed to assist with spasticity – the increased muscle tone seen in individuals with neurological conditions such as stroke or cerebral palsy. However, these devices typically lack the ability to individually assist multiple degrees of freedom (DOF), which is essential to performing a broad range of daily tasks. To address this need, we developed a soft robotic thumb orthosis to achieve movement in three DOF. We focused on the thumb as it performs the most complex movement. Our orthosis used three unfolding textile pneumatic actuators to assist with the extension of the interphalangeal joint, combined extension of the metacarpal and carpometacarpal joints, and abduction of the carpometacarpal joint. The orthosis was tested on both a 3D-printed biomimetic test bed that emulated spasticity and a healthy individual. The orthosis met the full range of motion targets for each joint, except for the abduction of the carpometacarpal joint with medium spasticity, and surpassed the range of motion threshold required for activities of daily living. The orthosis was able to: (1) assist each DOF independently, (2) move the tip of a biomimetic thumb to a pre-determined target with total error of less than 1.5 cm when actuated with open-loop control, and, (3) provide individual joint assistance to a user with no motor impairment. This research showcases the ability of a soft robotic orthosis to assist movement in simulated spasticity of individual thumb joints and provides an important step towards a platform to study whether independent joint assistance during rehabilitation improves patient outcomes.
Radiation effect in carbon fiber-filled polyethylene composites are of importance in space and aircraft applications. A two-fold approach is employed to study radiation effects in carbon nanotube polyethylene as the e...
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Polyvinyl alcohol(PVA)/laponite(LP)nanocomposite coatings were fabricated via a facile one-step coassembly *** formed nanocoatings contain a high concentration of LP nanosheets,which can be well aligned along the subs...
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Polyvinyl alcohol(PVA)/laponite(LP)nanocomposite coatings were fabricated via a facile one-step coassembly *** formed nanocoatings contain a high concentration of LP nanosheets,which can be well aligned along the substrate surface during the coassembly *** to the highly orientated structure,the flexible nanocoatings exhibit ultra-high transparency and superior mechanical properties,and can also act as excellent gas *** nanocoatings can be exceptional candidates for a variety of applications,such as food packaging.
It has been recognized that a small amount of propane mixed with methane can change greatly in not only the thermodynamics but also the structural properties of gas ***,its mechanism is still not well understood *** t...
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It has been recognized that a small amount of propane mixed with methane can change greatly in not only the thermodynamics but also the structural properties of gas ***,its mechanism is still not well understood *** this research,structure-Ⅱ(sⅡ)hydrate is synthesized using a methanepropane gas mixture with an initial mole ratio of 99:1,and it is found that large(5~(12)6~4)cages are cooccupied by multiple gases based on the rigid structure analysis of neutron diffraction *** first principles calculation and molecular dynamics simulation are conducted to uncover the molecular mechanism for sⅡmethane-propane hydrate formation,revealing that the presence of propane inhibits the formation of structure-Ⅰ(sⅠ)hydrate but promotes sⅡhydrate *** results help to understand the accumulation mechanism of natural gas hydrate and benefit to optimize the condition for gas storage and transportation in hydrate form.
The height of total entropy(S)for a magnetic refrigerant material is essentially concerned with the magnetic and structural ***,the participation of such transitions in layered materials is not well ***,the purpose of...
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The height of total entropy(S)for a magnetic refrigerant material is essentially concerned with the magnetic and structural ***,the participation of such transitions in layered materials is not well ***,the purpose of this work is to investigate the interplay between double layer lattice with their single perovskite counterpart,to achieve optimal magnetocaloric performance.A series of self-doped Pr_(1.4+x)Sr_(1.6-x)Mn_(2)O_(7)(0.0≤x≤0.5)Ruddlesden-Popper(R-P)perovskite have been prepared through the solid-state sintering *** increasing the Pr-stoichiometry,the lattice faults have increased and the double layer lattice dramatically disintegrates into single perovskite *** to the reduction of bilayer R-P phase into single perovskite the spin crossover occurs from weak bilayer(T=304 K)interactions towards the strong three-dimensional(T=308 K)interactions *** series consistently develops thermomagnetic irreversibility in zero-field cooled(ZFC)-field cooled(FC)magnetization,which is indicative of a spin-glass *** glassy nature has been ascribed collectively to the lattice strain produced because of dislocations and to an antiferromagnetic phase segregated at the *** maximum value of temperature average entropy change(TEC)and adiabatic temperature(ΔT)has enhanced nearly by 4 folds from 0.53 J kg^(-1)K^(-1),0.59 K(for x=0.0)up to 1.85 J kg^(-1)K^(-1),10 K(for x=0.5)at 2.5 T,***,the room temperature relative cooling power has improved from 26.94 J/kg up to 77.84 J/kg with an applied field of 2.5 *** findings in this work suggest that the controlled reduction of double layer lattice into single perovskite and/or existence of both phases simultaneously in bilayer R-P manganites may be very effective in obtaining the desirable characteristics of magnetocaloric effects.
Northeastern(NE) Thailand is well recognized as the land for rice cropping and consequently, it is potentially contaminated with chemicals from soil fertilization, pest/weed control, and urban *** Mun River basin in N...
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Northeastern(NE) Thailand is well recognized as the land for rice cropping and consequently, it is potentially contaminated with chemicals from soil fertilization, pest/weed control, and urban *** Mun River basin in NE Thailand principally is comprised of rice paddies and sedimentation in the river has been pronounced, but the studies on sediment source identification are limited. The current study aims to identify sediment sources in the Mun River basin and discuss possible impacts on ecosystems attributed to exposure to polluted sediment. The assessment relies upon physicochemical properties and heavy metal contents(iron(Fe), manganese(Mn), copper(Cu), chromium(Cr), nickel(Ni),and Zinc(Zn)) in the fine-grained sediment(<63 μm) taken from the Mun River basin and the Chi River in the dry season of 2020-2021. The findings revealed that the heavy metals in the sediment had not accumulated to levels of concern. Most sediment was from natural sources, including Fe-and Mn-rich sediment, Cr-dominant sediment, and Ni-and Cu-rich sediment. Fe-and Zn-rich sediment was, however, found in the urban watershed of Lam Ta Klong, and it could originate from mixed urban sources. Ferich sediment was predominant in the Mun River basin, which and could be a significant sink and source of toxic elements from agricultural and urban discharges. It is suggested that the toxic compounds in the sediment should be consistently monitored, whereas ecological and health risk assessment should be focused on the mobile forms.
Resistive Random-Access Memory(RRAM) devices are recognized as potential candidates for next-generation memory devices, due to their smallest cell size, high write/erase speed, and endurance. Particularly, the resis...
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Resistive Random-Access Memory(RRAM) devices are recognized as potential candidates for next-generation memory devices, due to their smallest cell size, high write/erase speed, and endurance. Particularly, the resistive switching(RS) characteristics in oxide materials have offered new opportunities for developing CMOScompatible high-density RRAM devices. In this study, the RS behavior of HfAlOx/ZrO2thin films sandwiched structure between TiN bottom electrode and Au top electrodes were investigated. It was found that Au/HfAlOx/ZrO2/TiN stacks were superior in terms of RS performance when compare to Au/HfAlOx/TiN memory stacks. The devices demonstrated a good resistance ratio of high resistance state and low resistance state ~103 for Au/HfAlOx/TiN and ~105 for Au/HfAlOx/ZrO2/TiN stacks, respectively. Both stacks showed good retention characteristics(>104s) and endurance(>103cycles). The experimental current-voltage characteristics fitted with different conducting mechanisms, the linear lower bias region is dominated by ohmic conductivity, whereas the non-linear higher bias region was dominated by space-charge limited current conduction mechanism.
studies have been widely carried out on drying techniques and equipment. The behavior of clays subjected to drying stages requires further research. This study aims to evaluate the behavior of the clay ceramic body du...
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