Publications by authors named "Chaofang Dong"

This paper investigates the local work function distribution of a multi-phase metal material at the nanoscale and examines how it is influenced by its surrounding components. A formula is derived to express the relationship between the local work function and neighboring phases, taking into account the solid angle they form. The study's findings indicate a positive correlation between the local work function and the neighboring phases.

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Water is generally considered to be an undesirable substance in fuel system, which may lead to microbial contamination. The antibacterial strategies that can turn water into things of value with high disinfection efficacy have been urgently needed for fuel system. Here, we reveal a water-fueled autocatalytic bactericidal pathway comprised by bi-metal micro-electrode system, which can spontaneously produce reactive oxygen species (mainly HO and O) by the electron Fenton-like reaction in water medium without external energy.

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In the electrochemical migration behavior (ECM) of printed circuit boards containing mold under a static magnetic field (SMF), the role of the field perpendicular to the electrodes is discussed; the field inhibits the growth and metabolism of mold, while controlling electrochemical diffusion and nucleation. The field indirectly affects the function of mold as a transmission bridge between two electrodes. In this work, the water drop test was used to simulate the adhesion and growth of mold on the circuit board in a humid and hot environment; confocal laser scanning microscopy, scanning electron microscopy, energy dispersive spectroscopy, Raman spectra, and a scanning Kelvin probe were used to analyze the mechanism of static magnetic field and mold on the electrochemical migration.

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Hydrogen (H) is viewed as an alternative source of renewable energy in response to the worldwide energy crisis and climate change. In industry, hydrogen production is mainly achieved through steam reforming of fossil fuels. In this research, hydrothermally-synthesized delafossite CuCrO nanopowder were applied in methanol steam reforming.

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Different microstructures were obtained under various thermal conditions by adjusting the heat treatment parameters of the Cr-Co-Ni-Mo series of ultra-high strength stainless steel. The effect of organizational evolution on the stress corrosion cracking (SCC) of the Cr-Co-Ni-Mo series of ultra-high strength stainless steel was investigated using potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and other test methods in combination with slow strain rate tensile tests (SSRTs). The results show that the Mo- and Cr-rich clusters and precipitation of the Laves phase reduce the corrosion resistance, while increasing the austenite content can improve the corrosion resistance.

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Recovery of platinum group metals (PGMs) from secondary resources has attracted worldwide attention from environmental and economic points of view. Pyrometallurgical routes exhibit the superiority in terms of efficiency and contamination control compared to hydrometallurgical process. However, traditional pyrometallurgical processes face the challenges of excessive flux and energy consumption.

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In this study, the phase transition of secondary phase particles in a composite coating is used to estimate the temperature field of the molten pool on a Ti6Al4V alloy in the micro-arc oxidation (MAO) process. The behavior of the sparks and the molten pool during the MAO process was observed in real-time by a long-distance microscope. The microstructures and compositions of the composite coatings were studied by scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD).

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Mold has a strong impact on the corrosion behavior of metals, especially under environmental conditions conducive to mold growth. However, the magnetic fields generated by electronic devices have effects on the metal corrosion and mold growth. In this study, a 10 mT static magnetic field (SMF) perpendicular to the surface of samples was applied to study the corrosion of a copper-clad printed circuit board (PCB-Cu) by mold under the SMF.

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In this research, the corrosion behavior of printed circuit boards with an immersion silver layer (PCB-ImAg) exposed to bacteria in Luria-Bertani broth was investigated. The growth test demonstrated that had a high copper tolerance. Analysis of surface and cross-sectional view of the samples after immersion test indicated that metabolites produced by accelerated the microporous corrosion of PCB-ImAg, and the biofilm that adhered to the surface led to oxygen concentration corrosion.

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The destructive role of chloride ions on the defect structure of barrier layers (bl) is vitally important for understanding the initial breakdown of passive films on metals. Here photo-electrochemical and density functional theory (DFT) were applied to investigate the influence of chloride on the defect structure of the bl in passive films. The results show a bl with a narrow band gap, in which the valence band maximum (VBM) increased upon introducing chloride into the electrolyte.

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Corrosion product formed on zinc sample during 2 weeks immersion in saline solution has been investigated. The corrosion layer morphology as well as its chemical composition, was analyzed using scanning electron microscopy (SEM), x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). Electrochemical measurement was used to analyze the corrosion behavior.

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MicroRNAs (miRNAs/miRs) have key roles in various physiological and pathological processes by regulating the expression of specific genes. The identification of miRNAs involved in bone metabolism may provide insight into the expression of genes associated with the development of alveolar ridge atrophy. In the present study, the miRNA expression profiles in alveolar ridge atrophy and normal tissue samples were investigated by miRNA microarray analysis.

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The corrosion behavior of metal materials in soil environments has been intensively studied recently. Even so, the detailed corrosion mechanisms remain elusive, especially regarding the role of metal ions. In this study, we investigated the effect of ion diffusion on the corrosion processes of carbon steel scanning electron microscopy (SEM), laser Raman spectroscopy and scanning Kelvin probe (SKP).

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In this study, we present a novel strategy for hierarchical antibacterial implant coating by controlling structural and componential features as regulators of surface bactericidal property. Anodized titanium dioxide nanotubes and self-polymerized polydopamine were both used as preliminary antibacterial agents with a significant positive effect on surface bioactivity. At the same time, the storage capacity of nanotubes and the in situ reduction activity of polydopamine can introduce large amounts of strong attached silver nanoparticles for enhanced stable antibacterial performance.

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The influence of Bacillus subtilis (BS) on tin-coated copper in an aqueous environment was investigated by exposing the sample to a culture medium inoculated with BS. Scanning electron microscopy, electrochemical measurements and chemical analyses were performed to study the corrosion mechanism. The experimental results show that BS can adhere and gather on the surface of the sample, resulting in oxygen consumption at the place where the bacteria are densely attached.

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Thin-layer indium selenide (InSe) compounds, as two-dimensional (2D) semiconductors, have been widely and intensively studied due to their high electron mobility and environmental stability. Here, we report a study demonstrating the oxygen-induced degradation of monolayer and bilayer InSe nanosheets using first-principles calculations and deformation potential theory. It is evident that O atoms prefer to substitute Se atoms instead of undergoing adsorption onto surfaces, while interstitial sites are the most stable adsorption sites of O atoms in the interior for both monolayer and bilayer InSe.

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Objective: In this work, we aim to determine the optimum pH value for the preparation of 3% yttria-stabilized tetragonal zirconia polycrystalline (3Y-TZP)/3%Al₂O₃ and optimum calcination temperature of Al₂O₃ precursor and amorphous boron nitride (BN) for Al₂O₃-BN coating 3Y-TZP powders.

Methods: The 3Y-TZP/3%Al₂O₃ composite powders were prepared through the heterogeneous precipitation method under different pH values (6.5, 7.

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The role played by mould in the electrochemical migration (ECM) behaviour of an immersion silver finished printed circuit board (PCB-ImAg) under a direct current (DC) bias was investigated. An interesting phenomenon is found whereby mould, especially Aspergillus niger, can preferentially grow well on PCB-ImAg under electrical bias and then bridge integrated circuits and form a migration path. The cooperation of the mould and DC bias aggravates the ECM process occurring on PCB-ImAg.

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This study investigated the mechanical properties and single crown accuracy of the tailor-made Fourth University Stomatology investment (FUS-invest) for casting titanium. . Current investment for casting titanium is not optimal for obtaining high-quality castings, and the commercially available titanium investment is costly.

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Purpose: To evaluate the physical and mechanical properties of pure titanium castings cast by self- made FUS-invest dental investment, and evaluate casting accuracy.

Methods: Seven pure titanium castings were cast by self-made FUS-invest zirconium investment and analyzed using servo hydraulic dynamic experiment system (JJG139-83 standard), scanning electron microscope and energy spectrum analysis. Thirty-eight crowns of pure titanium were cast by two different methods.

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The electrochemical corrosion behavior of a silver-plated circuit board (PCB-ImAg) in a polluted marine atmosphere environment (Qingdao in China) is studied through a simulated experiment. The morphologies of PCB-ImAg show some micropores on the surface that act as the corrosion-active points in the tests. Cl mainly induces microporous corrosion, whereas SO₂ causes general corrosion.

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The electrochemical migration (ECM) behavior of copper-clad laminate (PCB-Cu) and electroless nickel/immersion gold printed circuit boards (PCB-ENIG) under thin electrolyte layers of different thicknesses containing 0.1 M Na₂SO₄ was studied. Results showed that, under the bias voltage of 12 V, the reverse migration of ions occurred.

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The interfacial pH value has a marked effect on cell viability because the pro-mineralization activity of osteoblasts increases at alkaline extracellular pH, whereas the pro-resorptive activity of osteoclasts increases under more acidic conditions. To obtain the more favorable alkaline interface, we developed a novel nanotube layer that was incorporated with magnesium oxide on a titanium implant substrate (MgO/NT/Ti) via ethylenediamine tetraacetic acid (EDTA) chelation. This facile immersion-annealing process successfully created a homogeneous magnesium oxide layer with sustained release kinetics and superior hydrophilicity according to the surface characterization and microenvironment measurement.

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The applications of stainless steel are one of the most reliable solutions in concrete structures to reduce chloride-induced corrosion problems and increase the structures service life, however, due to high prices of nickel, especially in many civil engineering projects, the austenitic stainless steel is replaced by the ferritic stainless steels. Compared with austenite stainless steel, the ferritic stainless steel is known to be extremely resistant of stress corrosion cracking and other properties. The good corrosion resistance of the stainless steel is due to the formation of passive film.

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