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Arsenic in drinking underground water is highly toxic for human health. The FeOOH/γ-Al 2 O 3 was developed to remove arsenic from drinking underground water and characterized by transmission electron microscopy, surface area analyzer, X-ray diffraction and X-ray photoelectron spectrometer. Here, the effect of pH of solution, concentration of initial arsenate, temperature, and contact time on dearsenic efficiency was investigated, and the experiment data were fitted with different models which were assessed by regression coefficient (R 2 ). The results showed that the composite exhibited more excellent adherence to arsenic with the max uptake amount (4.264 mg g −1 ), compared to spherical and mesoporous alumina granules, and that the pseudo-second-order model was able to explain the adsorption kinetic process. The adsorption mechanism could be explained by a proton shifting mechanism. [ABSTRACT FROM AUTHOR]

In order to investigate the fatigue performance improvement of SiC w /Al composite under different shot peening (SP) treatments, conventional SP, warm peening (WP), stress peening (STP) and compound peening (CP) were carried out on SiC w /Al composite specimens. The fatigue test, residual stress measurement and full width at half maximum (FWHM) from X-ray diffraction measurement were conducted on different SP specimens. The fatigue strength of SiC w /Al composite specimen increases by 16%, 37%, 21% and 42% via SP, WP, STP and CP respectively. The surface mechanical properties such as quasi-static surface compressive yield strength ( R e(c),s ) and cyclic surface yield strength ( R cycl e,s ) were calculated via analyzing residual stress relaxation during cyclic loading. The results show that the decrement of R e(c),s and R cycl e,s caused by Bauschinger effect during shots' impact is compensated by dynamic strain aging effects in WP and CP. The degree of fatigue strength improvement is more obviously in WP and CP specimens, which is due to the improvement of stability of residual stresses caused by the dynamic strain aging effects in elevated temperature condition. [ABSTRACT FROM AUTHOR]

We report for the first time using pure cobaltous tungstate (CoWO 4) as an efficient ethanol sensor by controlling the Co3+-Co2+ redox couple in CoWO 4. The prepared Co x WO 4 has a flower-like structure self-assembled by a mesoporous microbelt. Moreover, the Co x WO 4 sensor with a Co3+/Co2+ ratio of 38.9% exhibits a high response (42.9–100 ppm ethanol), fast response/recovery time (11/13 s), low detection limit (0.42 ppm), as well as remarkable short-term and long-term repeatability. Notably, the Co x WO 4 sample maintains a constant response value over a wide range of humidity (30–90 RH%), manifesting its good anti-humidity properties. The outstanding sensing performance is owing to the Co3+-Co2+ redox couple, high surface area and moderate porosity of the obtained samples. The self-transforming of the Co3+-Co2+ redox couple contributes to the formation of absorbed oxygen (O 2 -), oxygen vacancies and the reduction of the band gap, which is a crucial factor in improving the sensing properties of Co x WO 4. • Pure cobalt tungstate was used for the first time as an efficient ethanol sensor. • The sensor shows a fast response/recovery time and low detection limit. • The self-transforming of Co3+-Co2+ redox on the surface is also a crucial factor. [ABSTRACT FROM AUTHOR]

In this work, nanocomposites with NiMoO 4 nanorod as core and NiMoS 4 nanosheet as shell with controlled sulfidation manner was obtained by one-step hydrothermal method. Characterization methods like scanning electron microscope and X-ray photoelectron spectrometer confirmed the well-designed core-shell structure and precisely-tuned composition. It exhibited superior electrochemical properties of high specific capacitance (832.3 F g−1 at current density of 5 A g−1), outstanding rate capability and stable cycling performance. With resultant as anode and reduced graphene oxide (rGO) as cathode, an asymmetric supercapacitor (ASC) was assembled and presented high energy density of 22.84 W h kg−1. Besides, cycling performance of the device is so outstanding that the capacity retention was up to 117.4% after 5000 cycles. Benefited from the synergistic effect between NiMoS 4 and NiMoO 4 components, large specific surface area and effective electron transportation from nanorod @ nanosheet structure, the excellent electrochemical performance indicates a good prospect of the material in the energy storage field. Image 1 • Complementary composition and well-designed structure was obtained simultaneously. • The resultant shows outstanding capacitive properties. • Assembled asymmetric supercapacitor exhibits excellent cycling performance. [ABSTRACT FROM AUTHOR]

The magnetic hexaferrite SrFe 12 O 19 (SFO, magnetic hard phase)/α-Fe (F, magnetic soft phase) composite nanowires (SFCNWs) with diameters about 100 nm and high aspect ratios have been synthesized by the organic gel-thermal selective reduction process. The SFO and F nanocomposites are formed after the selective reduction of the oxide precursor at 375 °C for 1 h. The magnetic property difference of these SFCNWs measured at 297 K and 77 K largely arises from the competition of magnetic exchange-coupling interaction and thermal fluctuation on dipolar interactions. With the mass ratios (SFO/F) increase, the minimum reflection loss ( RL ) with 3.0 mm thickness reaches the optimized value of −51.1 dB at 10.4 GHz for the mass ratio (SFO:F) of 7:3. While the microwave absorption bandwidth exceeding −20 dB with a thickness of 4.0 mm covers the whole G -band, X -band and 20% Ku -band. The comparison of microwave absorption for the nano- and micro-wires of SFO and F nanocomposites is also investigated. [ABSTRACT FROM AUTHOR]

• The Pt deposited porous SnO 2 nanospheres were synthesized by hydrothermal and chemical reduction method. • The Pt-SnO 2 sensors exhibited an overall enhanced formaldehyde sensing performance compared with the pure SnO 2. • The 1 wt% Pt-SnO 2 exhibited higher response (16.03), high-speed response time (9 s) and outstanding selectivity. This work constructs a Pt-SnO 2 sensor materials with the porous structures and catalytic effect, which great enhanced the sensing performance towards formaldehyde. [Display omitted] Formaldehyde is one of the most serious threats to human health in modern interior decoration. Thereby, online detection of indoor formaldehyde concentration has become an urgent problem. In this work, the Pt deposited porous SnO 2 nanospheres were synthesized as the formaldehyde sensing materials, which were prepared by hydrothermal and chemical reduction methods. The diameter of as-synthesized Pt-SnO 2 were centered in the range of 30–50 nm, with the dominant pore size of ~10 nm and the specific surface area of 89.79 m2 g−1, which provided a raft of passages and active sites for gas molecules to diffuse and interact mutually. Moreover, the experimental results demonstrated that the 1 wt.% Pt-SnO 2 exhibited higher response (16.03), high-speed response time (9 s) and outstanding selectivity with exposure to low-concentration formaldehyde compared with original SnO 2. The porous structures and catalytic effect of Pt nanoparticles were jointly responsible for the enhancement of SnO 2 on sensing performance towards formaldehyde. [ABSTRACT FROM AUTHOR]

• A specific and feasible method to fabricate specially designed one-dimensional structure. • A complicated nanostructure of the flakes-assembled porous ZnO/Ni hybrid nanotubes. • Revealing the inner attenuation mechanism of enhanced electromagnetic absorption performances. Flakes-assembled ZnO/Ni hybrid nanotubes were synthesized by electrospinning with hydrothermal treatment, calcination and reduction reaction for the electromagnetic wave absorption. The synergy effects between ZnO and Ni and absorbing mechanisms were investigated. [Display omitted] Electromagnetic (EM) wave absorption materials with excellent absorption performances are highly desirable because of military applications and EM radiation pollution protection. In this work, we have synthesized and demonstrated the flakes-assembled porous ZnO/Ni hybrid nanotubes by combining electrospinning and hydrothermal reaction, coupled with following calcination and reduction process. The rational-designed ZnO/Ni nanocomposites exhibited extremely superb EM wave absorption property with a minimum reflection loss (RL) of −71.2 dB at 15.3 GHz, corresponding to a thickness of 3.4 mm and the maximum effective absorption bandwidth (RL≤–10 dB) is up to 9.4 GHz (8.6–18.0 GHz) with the thickness of 4.2 mm. The significant performance improvement originated from that the unique three-dimensional architecture optimized impedance matching characteristics and magnetic-dielectric synergetic effect contributed to a strong attenuation capacity. This work provided a feasible strategy to synthesize flakes-assembled nanotube microstructure and the ZnO/Ni composites promised great potential in the EM wave absorption fields. [ABSTRACT FROM AUTHOR]

Abstract: Magnetic ions such as Fe3+ are usually doped into ferroelectric oxides in order to obtain multiferroic properties. Fe3+ as an acceptor dopant (substituted for Ti4+) in BaTiO3 ceramics usually promotes the formation of the hexagonal phase of BaTiO3. Based on the consideration of charge compensation for the acceptor dopant Fe3+ in Fe-doped BaTiO3 ceramics, we introduced donor dopants into the ceramics, and investigated the effects of donor doping on the phase structures and magnetic properties of the ceramics. We demonstrated that the phase structures of the Fe-doped BaTiO3 can be readily controlled by donor doping. In this work, we prepared Fe-doped BaTiO3 ceramics at a doping concentration of 10at% (or Ba(Ti0.9Fe0.1)O3) as a model system, and employed Nb5+ as the donor dopant for a charge compensation for the acceptor dopant Fe3+. It was found that the formation of the hexagonal phase in Ba(Ti0.9Fe0.1)O3 was consistently suppressed by Nb5+ donor doping. The magnetic properties of the Ba(Ti0.9Fe0.1)O3 ceramics were strongly influenced by Nb5+ doping. [Copyright &y& Elsevier]