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Liu Yunan Zhang Shanshan Li Guangyu Wang Houjun Yang Jian 《Pattern Analysis & Applications》2020,23(4):1551-1567
Pattern Analysis and Applications - Orthogonal moments have become a powerful tool for object representation and image analysis. Radial harmonic Fourier moments (RHFMs) are one of such image... 相似文献
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Black phosphorus is a potential candidate material for next-generation energy storage devices and has attracted tremendous interest because of its advantageous structural and electrochemical properties, including its large theoretical capacity, high carrier mobility, and low redox potential. However, its practical applicability has remained low owing to its difficult of preparation, large volume expansion during cycling, and poor electronic conductivity. To this end, there have been significant efforts to improve its synthesis methods and electrochemical performance. A number of black-phosphorus-based composite materials have been developed and investigated. Herein, we provide an up-to-date account of the recent progress made in research on black-phosphorus-based materials for use in rechargeable batteries and supercapacitors. We review the available synthesis methods and basic properties of black phosphorus and discuss its applicability in Li-, Na-, K-, Mg-, Al-ion and Li-S batteries as well as supercapacitors. We also summarize the existing challenges and future opportunities and offer our perspective on the possible directions for future research in this area. 相似文献
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A model is proposed for prediction of natural carbonation in reinforced concrete (RC) structures, and is potentially applicable to existing and new RC structures. The major components of the model comprise mathematical functions applied to predict the influence of concrete composition, and environmental factors on natural carbonation.This paper introduces the model concept and explains its structure including derivation, optimization and calibration. Over 163 data sets taken from a 10-year carbonation study were used in the model development and calibration. Only the experimental data that were based on outdoor natural exposure environment were employed in this research. Also in this study, the proposed model is compared with fib-Model Code 2010 using carbonation predictions generated from 346 data sets involving real world, highway structures. It is shown that the proposed model is comparably accurate and involves mainly basic tests with no major anticipated costs. 相似文献
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《Journal of the European Ceramic Society》2020,40(4):1532-1538
Dense Al2O3/Ti(C,N) composite ceramics reinforced with GNPs/nano-ZrO2 were fabricated by hot-press sintering. The effects of nano-ZrO2 content on the microstructure and mechanical properties of the prepared Al2O3/Ti(C,N)/GNPs/ZrO2 composites were investigated. Results showed that nano-ZrO2 inclusions refined the matrix grains significantly and resulted in the formation of intra-granular structure. Excellent comprehensive mechanical properties were achieved via addition of combined GNPs and nano-ZrO2. In particular, the fracture toughness of composites incorporating GNPs (0.4 wt%)/ZrO2 (1 wt%) exceeded 11 MPa m1/2, which was increased by more than 86 % compared with that of Al2O3/Ti(C,N) ceramic composites without GNPs/ZrO2. The main toughening mechanisms have been identified as stress-induced phase transformation, crack bridging, deflection and pull-out of GNPs. The toughening effects originated from GNPs were enhanced with the introduction of nano-ZrO2 because of not only the residual stress resulted from phase transformation but also the formation of intra-granular structure with uneven surface around GNPs. 相似文献
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《Ceramics International》2020,46(7):8601-8614
This paper investigates the physicochemical and thermo-physical properties of CaO–CaF2–SiO2 and CaO–TiO2–SiO2 based electrode coating for welding offshore structures. Twenty-one electrode coating compositions have been formulated using extreme vertices design method. The coating was crushed to powder form. The powder was characterized for weight loss, density, specific heat, enthalpy, thermal conductivity, diffusivity, and specific heat. Coating's structural analysis was done using X-Ray Diffraction and Fourier transformation. X-Ray Fluorescence, Thermogravimetric Analyzer, and Hot disc have been used to characterize the coating mixture. The regression analysis has been used to study the effect of individual constituents and their binary, tertiary interactions on the properties. The obtained output of properties has been optimized using multi-response optimization. 相似文献
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《International Journal of Hydrogen Energy》2022,47(6):3781-3790
A novel heterostructure of g-C3N4/ZnO/Bi4O5Br2 (ZB-3) was designed, and used in the microbial coupled photocatalytic fuel cell (MPFC). It can effectively improve electron utilization efficiency and pollutant degradation using this double Z-scheme heterojunction structure. The current–time (I–t) curves demonstrated that the current density of ZB-3 was higher than that of ZnO, ZnO/Bi4O5Br2 (ZB-1), g-C3N4/ZnO (ZB-2). Electrochemical impedance spectroscopy (EIS) indicated ZB-3 possessed the minimum charge-transfer resistance. This MPFC for degrading rhodamine B (RhB) and tetracycline (TC) under different conditions were developed using these materials. Even in the dark condition, MPFC with g-C3N4/ZnO/Bi4O5Br2 demonstrated 93% and 82% degradation efficiency for RhB and TC, respectively. Furthermore, the electron transport mechanism of the MPFC and ZB-3 were proposed. It paves the approach for more efficient pollutant degradation via MFC photocatalysis. 相似文献
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《中国有色金属学会会刊》2020,30(7):1731-1742
The microstructural features and the consequent mechanical properties were characterized in aluminium borate whisker (ABOw) (5, 10 and 15 wt.%) reinforced commercially-pure aluminium composites fabricated by conventional powder metallurgy technique. The aluminium powder and the whisker were effectively blended by a semi-powder metallurgy method. The blended powder mixtures were cold compacted and sintered at 600 °C. The sintered composites were characterized for microstructural features by optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis. Porosity in the composites with variation in ABOw contents was determined. The effect of variation in content of ABOw on mechanical properties, viz. hardness, bending strength and compressive strength of the composites was evaluated. The dry sliding wear behaviour was evaluated at varying sliding distance at constant loads. Maximum flexural strength of 172 MPa and compressive strength of 324 MPa with improved hardness around HV 40.2 are obtained in composite with 10 wt.% ABOw. Further increase in ABOw content deteriorates the properties. A substantial increase in wear resistance is also observed with 10 wt.% ABOw. The excellent combination of mechanical properties of Al−10wt.%ABOw composites is attributed to good interfacial bonds, less porosity and uniformity in the microstructure. 相似文献
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