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How to improve the high resolution and remove the noise of composite infrared thermal wave detection image have become important research topics in machine vision. Therefore, this paper proposes a composite image enhancement algorithm based on edge adaptive total variation of direction. Using the improved adaptive directional total variation model to construct the guidance image of the guidance filter can provide better structural information for the guidance filter and conduct the guidance filter. This process is iterated to eliminate noise and ladder effect. Experimental results show that this algorithm is superior to other advanced methods in objective evaluation index and subjective vision. The algorithm proposed in this paper can not only effectively eliminate noise and ladder effect, but also highlight image details and structure information, which proves the effectiveness of this algorithm. Discover the cutting-edge algorithm for high-resolution improvement and noise elimination in infrared thermal wave detection images. Our innovative composite image enhancement technique, based on edge adaptive total variation, outperforms traditional methods. The improved directional model provides better structural information, optimizing the guidance filter process. Experimental results reveal its superiority in objective evaluation and subjective vision. This algorithm effectively eliminates noise and ladder effect while highlighting image details, validating its remarkable effectiveness. [ABSTRACT FROM AUTHOR]

Quite a lot of engineering friction components serve at high temperatures, and are thus required to have excellent friction and wear resistance. The said study aims to fabricate high-wear-resistance coating on ordinary low-cost materials, achieving the low-cost manufacturing of some high-end friction components that are usually made with expensive solid alloys. The coating was prepared via laser cladding with a sort of widely used Fe-based self-fluxing alloy powder. The chosen substrate material was forged 42CrMo, which is popular in high-temperature friction engineering applications. In order to achieve the best possible high-temperature friction and wear properties, the prepared coating was turned and then ultrasonic burnished. Three samples, i.e., the substrate sample, the cladded sample without burnishing, and the cladded sample with burnishing, were prepared. For the three samples, the surface characteristics and friction properties at a 200 °C temperature were compared and investigated. According to the results, the cladded sample with burnishing exhibited the best surface finishing and friction behavior. Ultrasonic burnishing after cladding led to a further hardness improvement of 15.24% when compared with the cladded sample without burnishing. Therefore, ultrasonic burnishing is an effective low-cost post-treatment method for a wearable coating serving at a high temperature. [ABSTRACT FROM AUTHOR]

A kind of multiscale β-sialon grain-reinforced Al2O3 matrix composite ceramic tool material, named ASN, was prepared and studied. For the ASN, β-sialon (molecular formula: Si4Al2O2N6) was synthesized in situ by a hot-pressing and solid-solution reaction process. A total of six samples were prepared at varying sintering temperatures and holding times under vacuum conditions. The solid solution reaction mechanism of β-sialon, the phase composition, mechanical properties, microstructure, and strengthening and toughening mechanisms of the composite ASN were investigated. As a result, within the experimental parameters, an optimal ASN tool material was obtained under a pressure of 32 MPa and at a temperature of 1550 °C for 20 min. The tested mechanical properties of the optimal sample were as follows: flexural strength 997 ± 59 MPa, fracture toughness 6.4 ± 0.3 MPa·m1/2, Vickers hardness 18.2 ± 0.4 GPa, and relative density 98.1 ± 0.2%. According to crystal defect theory, the solid solution reaction mechanism of in-situ-synthesized β-sialon in an Al2O3 matrix involves a double mechanism of unequivalence (or hetero-valence) and interstitial filling. The multiscale β-sialon grains mainly consisted of four grains, which were elongated β-sialon grains with a diameter of 0.3–0.4 μm and an aspect ratio of 6–9, elongated β-sialon grains with a diameter of 70 nm and an aspect ratio of 10, β-sialon whiskers with a diameter of 0.2 μm and an aspect ratio of 12–15, and intragranular β-sialon whiskers with a diameter of 70 nm. The mechanical properties were improved due to strengthening and toughening mechanisms, such as mixed structure mode (intergranular and transgranular), elongated grain pullout, interface bonding, crack reflection, pinning, and bridging. [ABSTRACT FROM AUTHOR]

Mn–Ni bimetallic catalysts with different Mn/Ni molar ratios were synthesized by means of a facile hydrothermal reaction and applied for the removal of ozone. The physicochemical properties of prepared samples were systematically characterized, confirming that Ni was incorporated into MnO x lattice to form the amorphous Mn–Ni solid solution. Abundant grain boundaries in amorphous Mn–Ni solid solution facilitated the formation of a large number of oxygen vacancies. Synergistic effects of Mn and Ni improved low-temperature reducibility and lattice oxygen mobility on Mn1Ni1 (molar ratio of Mn2+: Ni2+ = 1:1). In situ diffuse reflectance infrared Fourier transform spectra (in-situ DRIFTS) analyses displayed that the introduction of Ni enhanced the hydrophobicity of Mn1Ni1 and avoided the enrichment of water molecules on the catalyst surface, but also promoted the conversion of adsorbed water into surface hydroxyl groups to participate in the ozone decomposition. The rapid desorption of intermediate peroxides (O 2 2−) on Mn1Ni1 accelerated the ozone decomposition cycle. Mn1Ni1 exhibited excellent activity and stability for ozone decomposition, keeping 100 % removal of 45 ppm ozone after running for 25 h under high relative humidity of 80 %. [Display omitted] • A novel amorphous Mn−Ni solid solution catalyst was prepared for ozone removal. • The formation of Mn−Ni solid solution generated abundant oxygen vacancies. • Ni enhanced preferential adsorption of ozone on oxygen vacancies. • The synergistic effect of Mn and Ni accelerated the desorption of H 2 O and O 2 2–. [ABSTRACT FROM AUTHOR]

The formation mechanism of surface texture for feed-direction ultrasonic vibration−assisted milling (UVAM) was investigated in this study by establishing a kinematic model and a pressing model of UVAM. The kinematic model showed that the cutter tip, which was supposed to be totally sharp, produced closed scratches by crossed trajectories. The variation trends of the interval for closed textures were of sine function. A comparative experiment was carried out by UVAM and conventional milling. A dividing line close to theXcoordinate divides the surface feature into two parts. The pressing model showed that the tool minor cutting edge left clear traces with certain width because of the tool minor cutting edge angle. Scratches by tool minor cutting edge were intermittent and regularly varied when feed-direction vibration was introduced. All the surface feature changes are in the radial direction and the trajectory intersections shall always be the scratch grooves or ridges. The ratio between ultrasonic vibration frequency and spindle speed, tool radius, and the located cutter rotation angle affected the changing rule of scratches by tool minor cutting edge. The analytical models and the experimental results proved to each other reasonable. [ABSTRACT FROM AUTHOR]