Low-emissivity Al-doped ZnO films were deposited on the surface of glass by direct current magnetron sputtering method. The infrared emissivity of sample was focused on. The structural ...characteristics were investigated by the X-ray diffractometry and scanning electron microscopy, while the properties were measured by a four-point probe, an infrared emissivity measurement instrument and an UV–Vis spectrophotometer. The results show that the infrared emissivity of the AZO film is affected by substrate temperature, working pressure and sputtering power. The film deposited at 200 °C, 1.0 Pa and 80 W possesses the lowest emissivity, 0.41. There is a very strong correlation between emissivity and resistivity. When the resistivity is low, the infrared emissivity increases with the increase of resistivity, following the Hagen-Rubens relationship. When the resistivity is high, the correlation between them decreases.
In the process of producing winding coils for power transformers, it is necessary to detect the tilt angle of the winding, which is one of the important parameters that affects the physical ...performance indicators of the transformer. The current detection method is manual measurement using a contact angle ruler, which is not only time-consuming but also has large errors. To solve this problem, this paper adopts a contactless measurement method based on machine vision technology. Firstly, this method uses a camera to take pictures of the winding image and performs a 0° correction and preprocessing on the image, using the OTSU method for binarization. An image self-segmentation and splicing method is proposed to obtain a single-wire image and perform skeleton extraction. Secondly, this paper compares three angle detection methods: the improved interval rotation projection method, quadratic iterative least squares method, and Hough transform method and through experimental analysis, compares their accuracy and operating speed. The experimental results show that the Hough transform method has the fastest operating speed and can complete detection in an average of only 0.1 s, while the interval rotation projection method has the highest accuracy, with a maximum error of less than 0.15°. Finally, this paper designs and implements visualization detection software, which can replace manual detection work and has a high accuracy and operating speed.
Graphene nanoribbons (GNRs) and nanographenes synthesized by on‐surface reactions using tailor‐made molecular precursors offer an ideal playground for a study of magnetism towards nano‐spintronics. ...Although the zigzag edge of GNRs has been known to host magnetism, the underlying metal substrates usually veil the edge‐induced Kondo effect. Here, we report the on‐surface synthesis of unprecedented, π‐extended 7‐armchair GNRs using 7‐bromo‐12‐(10‐bromoanthracen‐9‐yl)tetraphene as the precursor. Characterization by scanning tunneling microscopy/spectroscopy revealed unique rearrangement reactions leading to pentagon‐ or pentagon/heptagon‐incorporated, nonplanar zigzag termini, which demonstrated Kondo resonances even on bare Au(111). Density functional theory calculations indicate that the nonplanar structure significantly reduces the interaction between the zigzag terminus and the Au(111) surface, leading to a recovery of the spin localization of the zigzag edge. Such a distortion of planar GNR structures offers a degree of freedom to control the magnetism on metal substrates.
π‐Extended 7‐armchair graphene nanoribbon with unique termini structures was synthesized on Au(111) using 7‐bromo‐12‐(10‐bromoanthracen‐9‐yl)tetraphene as the precursor. A Kondo resonance was observed for termini with nonplanar zigzag edges even on a bare Au(111) surface. DFT calculations revealed that the recovery of the spin localization of the zigzag terminus resulted from its weak interaction with the Au(111) because of its nonplanar conformation.
Replacement of Dy and substitution of Nd in NdFeB‐based permanent magnets by Ce, the most abundant and lowest cost rare earth element, is important because Dy and Nd are costly and critical rare ...earth elements. The Ce, Co co‐doped alloys have excellent high‐temperature magnetic properties with an intrinsic coercivity being the highest known for T ≥ 453 K.
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