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Optimized design of polymeric composites that are comprised of polymers and commonly used fillers forms one of the key focuses in this community since it may enhance the feasibility of real applications in industries. In this work, we produced three different epoxy composite coatings through filling the diamond, SiC, MoS2 and graphite. Then, the influence of these fillers on friction and wear performance of the composite coating is investigated. Comparison of the net epoxy (EP), the fracture toughness and young's modulus of the epoxy composite coatings (GME) can be 37.4 GPa and 4.3GPa, respectively, much higher than those of unfilled EP, i.e. 25.45 GPa and 3.75 GPa. More importantly, inclusion of multiple fillers can significantly reduce the wear rate and frictional coefficient of the GME. They are mainly because the graft treatment of the diamond and SiC dispersed uniformly in EP leads to a strong interface between the particles and matrix, making GME showing higher mechanical properties. Furthermore, due to the lubricant fillers-MoS2 and graphite, a continuous and thick lubricant film were observed on the worn surface of the GME, which can effectively decrease the friction heating and further damage to the matrix. Therefore, the strategy presented here is a valid method to create positive synergetic effect of different fillers, which can serve as an important guidance for rational design of the epoxy composite coatings towards in further industrial applications.

Doping is an effective way to optimize the performance of thermoelectric materials. In order to investigate the effect of Bi doping on microstructures and thermoelectric properties of Ge0.90Pb0.10Te, a series of Ge0.90−xPb0.10BixTe compounds were prepared by a melting-quenching-annealing process followed by spark plasma sintering. The Bi doping on Ge site acts as an electron donor, which effectively optimized the carrier concentration from 1.1 × 1021 cm−3 to 3.5 × 1020 cm−3. Besides, the lattice distortions originated from Bi doping further promoted the solubility of Pb in the GeTe matrix, which have great advantage for obtaining lower thermal conductivity compared with pristine Ge0.90Pb0.10Te sample. Low lattice thermal conductivity of about 0.77 W/mK was obtained in Ge0.86Pb0.10Bi0.04Te owing to the additional lattice defects introduced by Bi doping. Consequently, the highest ZT of 1.1 was obtained in Ge0.86Pb0.10Bi0.04Te at 600 K with an average ZT of 0.6. These results have confirmed that Bi doing is an efficient way to boost the thermoelectric performance of GeTe-based alloys.

Fenton-like processes have emerged as most promising techniques for generating reactive oxygen-containing radicals to deal with increasing levels of environmental pollution. Developing novel catalysts with simple manufacturing requirements, excellent activity levels, and stability remains a long-term goal in terms of practical application. So herein, a new polyethylene terephthalate (PET) non-woven fabric based composite catalyst has been fabricated, using radiation-induced graft polymerization of a functionalized group to chelate Co2+ ions as heterogeneous catalysts in peroxymonosulfate (Oxone) activation. Several impact factors, including catalyst dosage, Oxone concentration, reaction temperature, pH value, Co2+ precipitation ratio (of Co@PET at different pH values), and highly concentrated NaCl have been investigated here. Notably, Co@PET has shown the lowest activation energy of any reported catalyst, for degrading RhB by activating Oxone. Interestingly, as experimental RhB and Oxone solutions were passed through single Co@PET sheets, the RhB was decomposed into a colorless solution in the penetration process. Based on radical trapping and quenching experiments, a channel was determined to dominate RhB degradation, and furthermore, Co@PET could be re-used for RhB degradation by activating Oxone. These results showed that Co@PET effectively provided improved Fenton-like catalytic performance and stability, and was suitable for practical applications.

Porous Mn 2 O 3 nanocubics, which were synthesized by a facile hydrothermal route followed by a calcination process, exhibited a specific capacitance of 191.1 F g −1 and a high rate capability with 58.6% specific capacitance retention even when the current density is increased by 50 times, and an excellent long-term cycle stability, and the fabricated simple symmetric supercapacitor was also fabricated and showed a good electrochemical performance, thus could be considered as a potential material for high-rate supercapacitors in some special applications that do not require a high capacitance.

The effects of secondary magnetic field originating from a permanent magnet on deposition rate, crystalline structure and photoelectric properties of Al-doped ZnO (AZO) films prepared by RF magnetron sputtering were systematically investigated. X-ray diffraction demonstrated that the films prepared using a secondary magnetic field were well aligned and textured along (0 0 2) orientation. SEM micrographs revealed that the grains became more compact and homogeneous with fewer defects in comparison to those grown by conventional magnetron sputtering (CMS). The deposition rate and lowest resistance of films prepared in the presence of a secondary magnetic field were 19.9 nm/min and 12.88 Ω/□, respectively. The average transmittance of all films in visible range was over 85% when the sputtering time was less than 60 min. The secondary magnetic field had a small influence on the transmittance of the films, but it caused a larger blue shift of the absorbance edge. Numerical simulations showed that the secondary magnetic field significantly changed the intensity and distribution of the transverse magnetic field in discharge space and caused a higher target current density.

Ferritic steels containing copper have been studied as model systems for clusters/precipitate formation in reactor pressure vessel steels. The samples were aged at 400 °C for 4000 h and subsequently cold rolled to 30% reduction at room temperature. The microstructural characteristics of the samples were analyzed using high-resolution transmission electron microscopy. Direct evidence was found that the fivefold twinning occurs via simultaneous emission of two Shockley partial dislocations from two particular α-Fe/Cu interfaces, and then the pileup tips of the twofold twin.

4 mol.% Y 2 O 3 stabilized ZrO 2 (YSZ) doped with various quantities of Gd 2 O 3 (G-YSZ) ceramic coatings were synthesized by electrophoretic deposition method, and followed by vacuum sintering and isothermally annealing at 1000 °C for different durations. X-ray diffraction (XRD) was used to investigate their phase composition. Scanning electron microscopy (SEM) was employed to examine their microstructure, while energy dispersive X-ray spectrometer (EDS) was used to assess composition of the composite coatings. The results indicated that YSZ coating was composed of tetragonal and monoclinic phase after vacuum sintering at 1000 °C for 2 h under vacuum ( −3 Pa). G-YSZ composite coatings were composed of tetragonal, monoclinic phase and a small amount of Gd 2 Zr 2 O 7 phase after vacuum sintering at 1000 °C for 2 h, whereas the content of monoclinic phase in G-YSZ composite coatings increased with increasing Gd 2 O 3 concentration. It was found that G-YSZ composite coatings were composed of tetragonal ZrO 2 phase, monoclinic ZrO 2 phase and cubic phase, whereas Gd 2 Zr 2 O 7 phase disappeared, after G-YSZ composite coatings were isothermally annealed at 1000 °C in air for 100 h. A detailed description of the results and their discussion was presented in the paper.

The TiN/Ni composite coatings were deposited on 7005 aluminium alloy by high speed jet electroplating and then processed with plasma transferred arc(PTA) scanning process. The microstructure, microhardness and friction coefficient of PTA scanning treated specimens were investigated. It is shown that the PTA scanning treated specimens have a rapidly solidified microstructure consisting of the uniformly distributed TiN phase and fine Al3Ni2 intermetallic phases. The composite coating has an average microhardness of approximately HV 800. The friction coefficient of PTA scanning treated specimens (oscillated at around 0.25) is considerably lower than that of TiN/Ni composite coating (oscillated at around 0.35). The corrosion behavior of the composite coating in 3.5% NaCl solution at room temperature was also determined using a potentiostat system. In comparison with the corrosion potential ϕcorr of −0.753 V for 7005 aluminium alloy, the corrosion potentials for TiN/Ti composite coating and PTA scanning treated specimen are increased by 0.148 V and 0.305 V, respectively. The PTA scanning treated specimen has the lowest corrosion current densityJcorr as well as the highest corrosion potential ϕcorr, showing an improved corrosion resistance compared with 7005 aluminium alloy.

Exchange coupling multilayer thin films, which combined giant magnetostriction and soft magnetic properties, were of growing interest for applications. The TbFe/FeAl multilayer thin films were prepared by dc magnetron sputtering onto glass substrates. The microstructure, magnetic, and magnetostrictive properties of TbFe/FeAl multilayer thin film was investigated at different annealing temperatures. The results indicated that the soft magnetic and magnetostrictive properties for TbFe/FeAl multilayer thin film compared with TbFe single layer film were obviously improved. In comparison with the intrinsic coercivity J H c of 59.2 kA/m for TbFe single layer film, the intrinsic coercivity J H c for TbFe/FeAl multilayer thin films rapidly dropped to 29.6 kA/m. After optimal annealing (350 °C×60 min), magnetic properties of H s =96 kA/m and J H c =16 kA/m were obtained, and magnetostrictive coefficient could reach to 574×10 −6 under an external magnetic field of 400 kAm −1 for the TbFe/FeAl multilayer thin film.