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Functional nanocomposites have been widely studied in recent years. Because of its non-toxic and inexpensive properties, titanium dioxide has pervasive application value in the chemical industry. Nano-sized antimony-doped tin oxide (ATO) metallic oxide was developed and combined with a pure titanium dioxide substrate by the effective co-precipitation method. The obtained powder had good conductibility, and its carriers were supplied by the infiltrated Sb atoms in tin oxide crystal. In the present work, the calcination temperatures and molar ratio of tin (IV) chloride pentahydrate (SnCl4·5H2O) and antimony (III) chloride (SbCl3) were optimized for achieving excellent electrical performances. As a result, the sheet resistivity of Sb-SnO2/TiO2 was in the range from 9 kΩ·cm to 15 kΩ·cm. By mixing method, the resistance of Sb-SnO2/TiO2/PDMS could be as low as 2 MΩ.

Yb2SiO5/mullite bi-layered coatings are promising environmental barrier coatings, but its molten salt corrosion mechanism is unclear. In this work, Yb2SiO5/mullite bi-layered coatings are fabricated by combining plasma spraying and dip-coating techniques. Residual stresses in the coatings caused by thermo-mechanical interaction are investigated by a nondestructive Raman spectrum method under high-temperature molten salt corrosion. In the as-deposited coatings, the stress in the mullite layer is compressive and the value near Si3N4 substrate is minimum. During high-temperature corrosion test, the residual stress near mullite-substrate interface changes sharply while the stress near mullite-Yb2SiO5 interface is concentrated without large fluctuation. An interfacial phase, YbAlO3, which is formed because of the inter diffusion of Al in the mullite layer and Yb in the Yb2SiO5 layer, causes the stress concentration. The change of SiO2 component in the mullite layer leads to the sharp change of residual stress near the mullite-substrate interface.

The transient traveling waves generated by linghting can be used to linghting location, in order to improve fault identifiaction ability of current traveling wave location device, an identification method of lightning strike and short circuit fault based wavelet energy spctrum and transient waveform characteristics was presented in this paper. Through researched the current signals generated by non-fault lightning strike, fault lightning strike and short-circuit fault on 220kV transmission line, compared of the energy distribution of different transient signals in each prequence band, realized the identification of lightning strike and short-circuit fault; for lightning identification, by waveform characteristics calculated obtaining eigenvalue to identify the non-fault and fault linghtning. PSCAD/EMTDC simulation results identicate that the proposed method is correct and effective.

By using part of speech information to similarity calculation of paraphrase sentences, the similarity calculation method is improved. The improved method includes multi information of paraphrase text, such as, matching words information and part of speech information. A small-scale comparing experiment of double negation sentence paraphrase for two method of similarity calculation has been done, and the experimental results indicated effect of improvement method.

In order to improve the fault location accuracy, and eliminate the influence of spectral leakage in power transmission line fault location, we proposed a novel fault location scheme for transmission lines based on multi-measurements and phase comparison with Kaiser self-convolution windows FFT, which can locate the fault between two adjacent towers in the fault-prone segment. It is based Kaiser self-convolution window's excellent performance of leakage suppression, which can effectively solve the phase current fault component is relatively large errors due to spectral leakage problem. Firstly, this paper analyzes the causes of the phase spectrum leakage, then elaborates the sidelobe characteristics of Kaiser self-convolution window, and lists phase comparative fault location using steps, finally, verifies the correctness of the proposed method by simulation. The results show that the proposed method can effectively suppress spectral leakage, has a high location accuracy, a wide applicability and its solving of phase difference is precise.

The present paper describes the compulsively short circuiting transfer phenomenon of welding current in rotational arc MAG welding. Based on a previously reported model of spray transfer welding, a mathematical model of the short circuiting transfer of rotational arc welding is proposed. A series of welding experiments had been conducted and it’s results show that short circuiting transfer would take place when the welding gun electrode rotating to the sides of V groove. The relationship between the short circuiting transfer frequency and the arc rotational frequency also had been studied.

With high pressure spraying refinement technology of explosive, we obtain ultrafine powder of TATB and HMX. The middle diameter of them is 746 and 242 , that is to say those two kinds explosives belong to ultrafine explosive. Impact test indicate that the impact sensitivity of ultrafine TATB and HMX is decreasing in some degree. However the shock sensitivity is increased and the increased range is big. The end, we analyze this phenomenon and explain the reason that the ultrafine explosives` sensitivity is different form usual explosive in theory.

The characteristics of welding current in rotational arc GMAW were analyzed in this paper. It was found that the compulsively short circuiting transfer would take place when the electrode rotating to the sides of V groove. During the period of short circuiting transfer, the welding currents would sharply increase, so as to affect the average value of welding current in one rotational cycle. A novel method was proposed to detect the height of welding gun in this paper. The method use of least-square fitting method to fit the welding currents into a plane in three dimensions, and then through compute the distance between origin of coordinates and the plane to detect the height of welding gun. In the last, the validity of the method was proved through experiments.