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Metal oxide semiconductor (MOSC) sensors based on nanocrystalline MoO3, In2O3, and their composites are considered to be very sensitive to detect low concentrations of ethanol, ozone, hydrogen, formaldehyde, and nitrogen dioxide. Here, we firstly introduced In2(MoO4)3 phase, which has excellent negative thermal expansion and high electric conductivity properties, into In2(MoO4)3@In2O3 crystalline nanocomposites. The gas-sensing performance of the In2(MoO4)3@In2O3 nanocomposites was studied upon exposure to the ethanol gas with different concentration from 5 to 300 ppm at the optimum temperature (300 °C). What's more, the device possesses ultra-high response of 110 and selectivity to ethanol. Particularly, it can effectively work in high humidity (RH = 80%) with super long-term stability of as long as 90 days, compared with the pristine In2O3 sensor and previous reports. The presented novel In2(MoO4)3@In2O3 sensor offers great opportunities for future ethanol detection under harsh conditions.

Spinel nickel ferrite (NiFe 2 O 4 ) nanoparticles with high specific area and excellent magnetic properties were synthesized via a template-assisted sol – gel method. The effects of template type on the structural properties, magnetic properties, and heating rate are investigated. Results of XRD and TEM indicate that the NiFe 2 O 4 particles synthesized using templates exhibit a typical single phase spinel structure in nano size. The sample using sponge or cotton as template presents the best saturation magnetization (66.6 emu/g) and the lowest coercivity (137.7 Oe), respectively, and their specific surface area is enhanced greatly from 20.1 m 2 /g to 55.7 m 2 /g. It is found that the calculated hysteresis loss agrees well with the measured radio frequency heating rate.

By using the extended hyperbolic function approach, we explore the discrete (2 + 1)-dimensional Toda lattice and the discrete Hybrid lattice, and successfully obtain some new exact soliton solutions, including the discrete kink-type soliton solution, bell-type soliton solution and some other types of soliton solutions.

In order to investigate the influence of the arrangement of the carbon nanotubes (CNTs) array on the field emission, the more practical model in hexagon was proposed. From the calculation with the image floated sphere model, the results showed that the arrangement has little influence on the field emission and the intertube distance R of CNTs array critically affects the field emission from the CNTs array, which accords with the results from the numerical simulations and experiments. When R is less than the height of tube h , the enhancement factor decreases rapidly with R . Considering the field emission current density, the field emission can be optimized when R is comparable with h , which accorded with the results from experiments. Furthermore, the influence of the anode–cathode distance d on the field emission from CNTs array was also discussed, which proved that d has little effect on the field emission from CNTs array. For the fixed field strength E for the certain materials in filed emission, we can reduce the threshold voltage to some extent by decreasing d in the case of R > 2 h .

We present a magnetic force microscopy and atomic force microscopy study of magnetic and crystalline microstructures of melt-spun binary Fe 50+ x Pt 50− x ( x= 0−20) and ternary (Fe 0.5+ y Pt 0.5− y ) 82 B 18 ( y= 0−0.2) nanocomposite ribbons. It was confirmed that an ordered magnetically hard γ 1 -FePt phase could be fully formed at x⩽ 10 in Fe 50+ x Pt 50− x ribbons. From the topographic images of the Fe 50+ x Pt 50− x and (Fe 0.5+ y Pt 0.5− y ) 82 B 18 ribbons, it was found that the average crystal size D ¯ is large (∼1.1–3.9 μm) for the Fe 50+ x Pt 50− y ribbons without B, but that of the (Fe 0.5+ y Pt 0.5− y ) 82 B 18 ribbons with invariable B content is much small ( ∼ 57–65 nm). Moreover, the magnetic force images with distinct contrast could be detected by MFM only in the ribbons with strong exchange-coupling interaction. Finally, it was found that for exchange-coupling nanocomposite ribbons, the strength of the exchange-coupling interaction can be reflected roughly by the root-mean-square roughness of phase shift, ( Δ φ ) rms , of magnetic force images and the ratio of the average domain width w ¯ to the average crystal size D ¯ .

The growth behavior and surface morphology of a rough film system, deposited on silicone oil drop surfaces by a r.f. magnetron sputtering method, have been studied. An anomalous film growth relaxation is observed during the deposition process. The relaxation rate is extremely sensitive to the substrate temperature. The surface morphology at the micrometer length scale is very susceptible to the substrate temperature, the incident r.f. capacity, and the nature of the solid substrate on which the oil drop is dripped. A discussion on the physical origins of these phenomena is also presented.

A wedge-shaped Pt-film percolation system was prepared by the magnetron sputtering method. A new nonlinear I-Vbehavior was found and can be well explained by the location-dependent hopping effect. Power-law behavior, σ(ω) α ωx and ϵ(ω) α ω−y, is observed near the percolation threshold. The exponents x and y are found to be 0.87±0.04 and 0.08±0.03, respectively, in agreement with the general scaling relation x + y = 1.