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A novel hierarchical Au/Ni/boron-doped diamond (BDD) heterostructure electrode was fabricated by two-step heat-treatment. The heterostructure that hierarchical Au/Ni nanoparticles are embedded on the surface of BDDwas demonstrated by transmission electron microscope (TEM). Cyclic voltammetry (CV) and amperometric detectionwere used to test electrochemical properties of the prepared electrodes. The Au/Ni/BDD electrode exhibited enhanced catalytic activity and stability in glucose detection, as compared to that of the Au/BDD and Ni/BDD electrodes. On the optimal NaOH concentration and applied potential, the Au/Ni/BDD electrode exhibited an extremely wide detection range of 0.005-32 mM with high sensitivity of 1229.5 µAmM-1cm-2 and an excellent long-term stability (maintains 94.8% of initial current after one month). In addition, the prepared electrode also exhibited a low detection limit of 2 µM (S/N= 3), good selectivity and reproducibility. At last, the reasons for enhanced catalytic activity and excellent stability of Au/Ni/BDD electrode were discussed. [ABSTRACT FROM AUTHOR]

In this study, the microstructure of boron-doped diamond (BDD), such as grain size, grain boundaries, surface boron concentration, film thickness, ratio of sp(3)/sp(2) was manipulated by adjusting the deposition parameters of hot filament chemical vapor deposition. Furthermore, Reactive orange 1 simulated dye wastewater was treated to discuss the degradation relationship between themicrostructure of BDD electrodes and oxidation parameters. BDD electrode showed the worst electrocatalytic performance toward simulated dye wastewater, but exhibited the highest sensitivity to degradation parameters. In addition, the degradation processes of 8 kinds of synthetic dyes with different molecular structures were compared and the degradation relationship between the microstructure of BDD and the molecular structure of dyes was investigated. The degradation of refractory dyes were much more dependent on the microstructure of BDD electrodes compared to easily degradable ones, indicating that the optimization of oxidation parameters and the electrode microstructure are more effective to the degradation of refractory organic pollutants. [ABSTRACT FROM AUTHOR]

A hybrid non-enzymatic glucose sensor made by incorporating boron doped diamond (BDD) film electrode with nickel (Ni)- encapsulated carbon nanotubes (CNTs) were facilely fabricated. The CNTs were grown directly on BDD films in the presence of pre-sputtered Ni layer as a catalyst by hot-filament chemical vapor deposition. The morphology and composition of the hybrid structure were assessed by scanning electron microscopy and Raman spectroscopy. As Ni layer thickness increased, the CNTs were less covered on the surface and the length of CNTs increased. The Ni particles were encapsulated into a large number of CNTs. Electrochemical results indicated that this hybrid structure significantly improved the electrochemical performance of BDD due to the increased specific surface area and synergistic effect of Ni and CNTs. The optimized glucose sensor revealed two broad linear range of 1.25 µM- 0.49 mM and 0.49 mM- 6.79 mM, with a high sensitivity of 1642.20 µAmM -1 cm-2 (R2 = 0.9988) and 1374.4 µAmM-1 cm-2 (R2 = 0.9969) respectively. In addition, the hybrid electrode exhibited a low limit of detection which was 1.0 µM (S/N = 3), and good selectivity and stability. [ABSTRACT FROM AUTHOR]

Niobium (Nb) and nitrogen (N) co-doped diamond-like carbon (DLC) film ((Nb:N)-DLC) was fabricated by reactive magnetron sputtering. Atomic force microscopy, Raman spectra and X-ray photoelectron spectroscopy were used to characterize the morphology, microstructure, and composition of the (Nb:N)-DLC film. The (Nb:N)-DLC film has typical DLC characteristics with enlarged and uniform specific surface area. Electrochemical tests show that the proposed co-doped DLC electrode not only presents fast apparent rate constant (1.92 x 10-2 cm s-1), low charge transfer resistance (13.86 Ω cm²), but also possesses excellent electrochemical reversibility and stability in K3Fe(CN)6 electrolyte. Furthermore, the (Nb:N)-DLC electrode was applied to the determination of dopamine (DA) and an apparent current response to a low concentration of 0.5 μM was obtained by differential pulse voltammetry. [ABSTRACT FROM AUTHOR]

Ultrananocrystalline diamond film was deposited by microwave chemical vapor deposition (CVD) system using Ar-CO 2 -CH 4 as gas source. The effects of process conditions on the morphology of diamond film were investigated. Results show that the compact ultrananocrystalline films with thickness of 5 μm, crystal size of 20 nm and surface roughness below 16 nm can be deposited. The deposition rate is significantly improved by adding CO 2 into the Ar-CH 4 system. However, the parameter window of gas source for the deposition of compact nanodiamond films is quite narrow when this gas source is employed. Further research is needed to investigate the reasons and optimal process condition. [ABSTRACT FROM AUTHOR]

Abstract: Mine production is along with water, fire, gas and coal dust, roof and other complex natural disasters and with the characteristics of poor, dangerous working conditions. Internet of Things (IOT) as an emerging technology provides a new technique for safety and security to underground production. According to the needs of mine safety production, key technologies of Internet of Things are introduced. That the technologies are RFID technology used to label things, sensor technology used to percept things, intelligent technology used to think about things, and intrinsic safety technology. Mine IOT key technologies and the research content are analyzed in-depth which have provided a direction for the research and application of mine IOT. Emphasis on IOT fundamental theories research, breakthrough in core technologies and strengthen research on key technologies that all these will effectively promote technology innovation in mine safety production. [Copyright &y& Elsevier]