One of the primary hurdles in microdevice fabrication lies in ascertaining the most impactful tactics for adapting metal surfaces. Through a one-pot tackle and distinct mechanochemical reactions evoked by 15 min aqueous wet sand-milling (SM-15), we successfully grafted Mo-based metal-organic frameworks (Mo-MOFs) onto graphene oxides (GOs). Following this, a convenient and readily scalable methodology of electrophoretic deposition was implemented to create controllable thickness of SM-15 GOs@Mo-MOFs lubricating films, achieving considerable enhancements of 143% and 91% in hardness and Young's modulus, respectively, when compared to those of SM-15 Mo-MOFs.
View Article and Find Full Text PDFSubstituting the sluggish oxygen evolution reaction with the sulfur oxidation reaction can significantly reduce energy consumption and eliminate environmental pollutants during hydrogen generation. However, the progress of this technology has been hindered due to the lack of cost-effective, efficient, and durable electrocatalysts. In this study, we present the design and construction of a hierarchical metal sulfide catalyst with a gradient structure comprising nanoparticles, nanosheets, and microparticles.
View Article and Find Full Text PDFWavefront phase retrieval is one of the most critical problems in adaptive optics. Here, phase retrieval by solving the transport of intensity equation using membrane vibration modes is proposed. Our study shows that the wavefront curvature sensing signal on the pupil can be expanded as a set of corresponding membrane vibration modes.
View Article and Find Full Text PDFThe elastic modes of a general circular thin plate (EMCTP), reflecting the natural deformation of the resonance, are applied to the diffraction theory of the optical aberrations in this paper. Our work has shown that the mode shapes of the EMCTP resemble those of the Zernike polynomials. As an application example, the compensations of some low order aberrations of the 2.
View Article and Find Full Text PDFIt is a common problem in precise submillimeter-wave telescopes that thermal deformation coupling between major subsystems results from materials with different coefficients of thermal expansion or at different temperatures. Here, the method of combining thermal homology theory with a genetic algorithm (CTHTGA) is proposed for the design and optimization of large precise submillimeter-wave antennas. The CTHTGA method has two key steps: (1) design of the structure of the antenna according to thermal homology theory; and (2) structural optimization based on the genetic algorithm.
View Article and Find Full Text PDFIn this work, our theoretical results first demonstrate that varying the metal valence in MOFs plays a significant role in tuning their stable intrinsic electronic structure. Different valence Fe(ii) and Fe(iii) based pristine MOF-74 nanoarrays on nickel foam are further synthesized as electrodes for highly efficient electrocatalytic water oxidation.
View Article and Find Full Text PDFIn this paper, an elastic mode method of deformable mirror is proposed to decompose arbitrary wave-front errors of adaptive optics system. The elastic modes are derived with an analytical method of linear piezoelectricity based on a bimorph piezoelectric deformable mirror (BPDM), and the three-dimensional formulas of elastic modes are presented. Here a BPDM with an aperture of 165 mm as an example is numerically studied.
View Article and Find Full Text PDFPerovskites, which have excellent electrocatalytic properties, are promising for use in heterogeneous catalysis. However, the design and development of green and effective electrocatalysts for environmental water treatment remains an arduous challenge. To overcome such difficulties, we present a facile sol-gel method for the design and preparation of a series of perovskite-activated carbon (AC) composites (La Nd FeO@AC) for the degradation of methyl orange (MO) by heterogeneous electro-Fenton reactions.
View Article and Find Full Text PDFWe have proposed a discrete-layout bimorph piezoelectric deformable mirror (DBPDM) and developed its realistic electromechanical model. Compared with the conventional piezoelectric deformable mirror (CPDM) and the bimorph piezoelectric deformable mirror (BPDM), the DBPDM has both a larger stroke and a higher resonance frequency by integrating the strengths of the CPDM and the BPDM. To verify the advancement, a 21-elements DBPDM is studied in this paper.
View Article and Find Full Text PDFWe have proposed a multi-variable H-β optimization approach (MHOA). Compared with the conventional push-pull-shear lateral support optimization (CPLSO), which has only one design variable, β, MHOA adds another design variable, H, which is the support position height. By contrast, the support position height of CPLSO is usually fixed at mid-thickness, H (or at H, the height of the center of gravity for the mirror), on the outer rim of the mirror blank.
View Article and Find Full Text PDFA theoretical analysis of the thermal effects of a circular bimorph piezoelectric actuator (CBPA) was performed. The circular bimorph structure consists of two flexible piezoelectric ceramic layers and one metallic layer in the middle, and is powered to produce flexural deformation. The CBPA, which may be a good match for large adaptive optics telescopes, has a large stroke and a high resonance frequency.
View Article and Find Full Text PDFA thin film of polyaniline (PANI) nanofibers on the stainless steels with fluoro-thiol modification was prepared through an optimal polymerization time of aniline using HClO4 as a dopant, showing robust superhydrophobic, transparent and anti-fingerprint properties.
View Article and Find Full Text PDFIEEE Trans Ultrason Ferroelectr Freq Control
April 2013
We propose a new structure consisting of a piezoelectric spring-mass system as a low-frequency piezoelectric energy harvester. A theoretical model is developed for the system from the theory of piezoelectricity. An analysis is performed to demonstrate the low-frequency nature of the system.
View Article and Find Full Text PDFIEEE Trans Ultrason Ferroelectr Freq Control
April 2013
We studied the weakly nonlinear behaviors of a simply-supported multilayer circular piezoelectric plate-like transformer (MCPPT) operating near resonance, where the MCPPT consists of a multilayer circular piezoelectric compound plate with four piezoelectric layers polarized in different directions. Nonlinear effects of large deformations near resonance are considered; it is shown that on one side of the resonant frequency, the output-input relation becomes nonlinear, and the other side, the output voltage becomes multivalued.
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