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To develop new environmentally friendly and recyclable high-voltage cable insulation materials, the effects of the particle size of zinc oxide (ZnO) on the mechanical and electrical properties of nanocomposites were investigated based on a feasibility study of polypropylene (PP) as a high-performance cable insulation material. The small particle size of ZnO can synergistically toughen PP with a polyolefin elastomer (POE), but the large particle size of ZnO leads to lower elongation at break. Adding ZnO nanoparticles can improve the bulk resistivity of the composites and suppress space charge injection. 0.5ZnO200 has the highest direct current and alternating current breakdown field strengths, 36.6% and 14.7% higher than PP/POE, respectively. This improvement may be due to the ability of 200 nm ZnO to introduce more deep traps. However, as the nanoparticle content rises and the particle size decreases, the agglomeration becomes more frequent, leading to the overlap of inter-nano interfaces and reducing the modification effect of the nanoparticles. This study on the effect law of nano-ZnO with different particle sizes on the microstructure, mechanical properties, and electrical properties of PP can provide a reference for developing new recyclable high-voltage insulated cable materials. KEYWORDS dielectric properties, mechanical properties, nanocomposites, nanoparticles, polypropylene (PP), 1 | INTRODUCTION Cross-linked polyethylene high-voltage cables have been widely used in recent decades. Yet, cross-linked polyethylene is a thermosetting material that is unrecyclable at its end of life. [1] [...]

The sensitivity of semiconductor sensors based on tin (Sn[O.sub.2]), tungsten (W[O.sub.3]), and zinc (ZnO) oxides and Sn[O.sub.2] with catalytic admixtures of [La.sub.2][O.sub.3] and CuO to hydrogen sulfide is studied at [H.sub.2]S concentration 50 ppm in dry air in the temperature range 100-600°C. Concentration dependences for oxides are studied in the temperature range 350-450°C and [H.sub.2]S concentration range 0.5-100 ppm at the humidity of gas media 0-80 rel. %. It is shown that, under the specified conditions, the resistance and of sensors to [H.sub.2]S in air weakly depends on humidity. It was found that sensors based on Sn[O.sub.2] with an admixture of 3% [La.sub.2][O.sub.3] working at 350°C are the best for the registration of [H.sub.2]S by the set of performance and operation characteristics. A presumable mechanism of [H.sub.2]S interaction with oxide surfaces is considered, according to which each [H.sub.2]S molecule releases seven electrons to the conductivity zone of the oxide and molecules of metal oxides in the surface layer are, possibly, partially replaced by sulfide molecules. Keywords: gas sensitivity (response) to [H.sub.2]S, metal oxide, sensor, humidity DOI: 10.1134/S1061934814020105, Among toxic and explosive gases hydrogen sulfide occupies a leading position. It accompanies processes of methane recovery from gas wells on nonassociated gas fields (for example, Astrakhan and Orenburg) and [...]

The article studies the current-voltage mechanism of low-ideality factor ZnO Schottky diodes over temperature range of 40-423 K. Findings revealed that TE was a major current transport mechanism at RT and above.

A study was conducted to examine the above-threshold characteristics of amorphous silicon Zn-based oxide (ZnO) thin-film transistors (TFTs) using exponential tail-state distribution model. Findings suggested that an exponential tail-state distribution model could be used to explain the above-threshold behavior of ZnO TFTs.

A study was conducted to compare the mutual interactions amongst the top-and bottom-gate fields in a dual-gate structure for amorphous InGaZn[O.sub.4] (a-IGZO) and hydrogenated amorphous silicon thin-film transistors (TFTs). Findings conclude the limited penetration of band bending into the a-Si:H layer.

Zinc-oxide-based thin-film bulk acoustic wave (BAW) resonators are examined with respect to variation of dimensions of a boundary frame spurious mode suppression structure. The simple semi-2-D plate model has predicted the device behavior, the 2-D finite element method results have coincided with them with some additional effects and breaking the resonator behavior down to eigenmodes have provided insights into the physics of the device operation.

Constant-voltage-bias stress measurements are conducted on thin-film transistors (TFTs) with amorphous indium-gallium-zinc-oxide (IGZO) channel layers prepared by using radio frequency (RF) sputtering using a postdeposition annealing temperature. The instability and hysteresis observations are found to be consistent with a Si[O.sub.2]/IGZO TFT instability mechanism involving electron trapping within the IGZO channel layer.

Lightning arresters provide protection for transmission lines and power equipments. During the occurrence of lightning or switching surges, a voltage level above the equipment insulation level can be reached. An arrester, properly working, is able to limit this voltage level avoiding damages to the protected equipment. A defective arrester may not be able to provide the proper protection level in substations, exposing the equipment and personnel to damage. Monitoring of surge arresters is usually conducted by means of current measurement or thermal images acquisition. But, among power companies, there is no model procedure for the monitoring conduction and analysis of the obtained results. Besides that, when some abnormality is detected, the arrester is replaced by a new one and no further study is conducted to evaluate what kind of problem happened to it. This work proposes a method for analysis of ZnO arresters by the study of failures and usage of artificial neural networks-ANN. The ANN is able to analyze the thermal profile, detect and classify patterns that could be undetected by a visual analysis. Index Terms--Arresters, artificial neural networks, power system monitoring, thermograph, zinc oxide.

The performance of resistance random access memory (RRAM) devices based on spin-coated sol-gel-derived zinc oxide (ZnO) thin films is examined. The devices are fabricated on a flexible plastic substrate and have displayed excellent durability upon repeated bending tests, thus showing their potential for flexible low-cost memory devices.

A combinatorial RF sputtering technique is used to fabricate thin-film transistors by using a semiconductor of the form [(ZnO).sub.x] [([In.sub.2][O.sub.3]).sub.1-x]. The devices fabricated with a zinc oxide fraction of 0.67 (plusminus) 0.02 have displayed the highest mobilities of 35 [cm.sup.2]/V * s for 300 degree Celsius annealing conditions.

The propagation characteristics of the shear horizontal surface acoustic wave (SH-SAW) in ZnO textured ZnO films are described. The SH-SAW device consisting of ZnO film could find potential use as candidate for a liquid sensor that detects changes in the electrical conductivity and relative permittivity.

Silicon nitride films of different refractive indices are used to study the effect of hydrogenation of ZnO TFTs by plasma-deposited silicon nitride gate dielectric. Secondary ion mass spectroscopy study show that in ZnO TFT using high refractive index silicon nitride, gate dielectric is higher that TFTs with low-refractive index silicon nitride, which is indicative of the hydrogenation of ZnO TFTs by high refractive index silicon nitride gate dielectric.

The performance of zinc-oxide (ZnO) elements is strongly dependent on the properties of the boundaries between ZnO grains, which are greatly affected by the formation of spinel particles between ZnO grains during the sintering process. The authors studied the effects of reducing spinel particles on the performance of elements and found that the characteristics of the spinel-reduced elements were improved compared with that of normal elements (e.g., superior voltage-current characteristics, smaller micropores, and larger capacitance). It was also found that the sintering temperature of the spinel-reduced elements could be decreased by more than 100[degrees]C than that of normal elements. Index Terms--Arresters, energy absorption capability, protective characteristic, zinc-oxide (ZnO) elements.

Superconducting Fault Current Limiters (SCFCLs) have improved the reliability and stability of power systems, which consists of a transformer type inductive SCFCL with a ZnO device and a resistor in parallel. The contribution share of the voltage drop suppression and the acceleration energy consumption to the improvement of the power system stability are clarified with conditions like generator output and fault clearing time.

A comparative study of the performance and stability of the zinc oxide (ZnO) thin-film transistors (TFTs) and silicon dioxide and nitride as the gate insulators is presented. The devices with SiN dielectric are shown to perform better than the devices containing silicon dioxide.

A standard ion-exchange technique was used for the fabrication of channel optical waveguides in novel Er-doped and Er-Yb co-doped ZnO-containing silicate glasses. Findings reveal the simulation of very large net optical gain for an ideal overlap of the pump and signal optical field in a glass containing at 3% of Er and no Yb.

dc conductivity and ac impedance measurements were made in air and in vacuum on samples of low density polyethylene to which nano-sized and micro-sized ZnO particles and a dispersant had been added. The samples were 150-200 [micro]m thick. The temperature range was 30-70 [degrees]C. The temperature dependence of the vacuum dc conductivity in samples containing the dispersant and 10% w/w nanosized ZnO followed an Arrhenius relationship closely, the conductivity being 1-2 orders of magnitude lower than that of a sample containing dispersant only. The addition of 10% w/w microsized ZnO had very little effect on the dc conductivity. The ac measurements were made in the frequency range 10 mHz--1 MHz. Addition of nanoparticles increased the ac conductivity at higher frequencies but decreased it at lower frequencies, the cross-over frequency increasing with increasing temperature. The real part of the relative permittivity of samples with nanoparticles was increased relative to that of samples containing dispersant only, at all temperatures, but the corresponding values in samples with microparticles were unchanged, within experimental error. Space charge profiles were obtained using the laser-intensity-modulation-method (LIMM). Space charge densities of order 300 [Cm.sup.-3] were measured in the bulk near the electrodes, several hours after poling at field strengths around 30 kV/mm. Index Terms--dc conductivity, ac impedance, space charge profiles, nanosized ZnO, microsized ZnO.

The energy absorption capability is a key parameter for ZnO varistors. This paper discusses the nonuniformity of energy absorption capabilities of ZnO varistors. With experiment results, we show that energy absorption capabilities of ZnO varistors can be highly scattered, for different commercial varistors, and for the same varistors under diverse current waves. We explain this nonuniformity phenomenon through numerical simulations, based on the microscopic circuit and heat transfer models of ZnO varistors. How the applied current, the nonuniformity of microstructure, and the nonuniformity of microstructural electrical and thermophysical characteristics influence the energy absorption capabilities of ZnO varistors is also analyzed. Index Terms--Current concentration, energy absorption capability, impulse current, nonuniformity, ZnO varistor.

A chemical bath deposition process for zinc oxide (ZnO) deposition is used for demonstration of solution-processed transparent ZnO transistors. The process results in high mobility of 3.5 [cm.sub.2]/V.s with on-off ratios of approximately [10.sup.5].

The experimental results on transition metal doping of ZnO is reviewed and the material that can be made with a single phase at high levels of Co incorporation is shown. Solutions involve either cubic phase ZnO or the use of additional stressor layers to create a larger spin splitting in order to get a polarized light emission.

Textured ZnO films that were fabricated with a high electromechanical coupling coefficient k(sub 15) are discussed. Experiments have showed that the film has a lot of potential for use in shear-mode FBAR and SH-type SAW devices.

One-dimensional (1-D) ZnO nanostructure arrays, such as nanowires, nanonails and nanotrees, are synthesized by oxygen assisted thermal evaporation of metallic zinc on a quartz substrate over a large area. The optical and electrical properties of the ZnO nanowire and nanonail arrays and also the applicability of these ZnO 1-D nanoform arrays as gas sensors are investigated.

Electromagnetic emission at the very high frequency (VHF) range of 30 to 300 MHz is used to detect surface defects on outdoor polymer zinc oxide (ZnO) surge arrestors. The partial discharge related signals are recorded and studied. Since the surge arrestors are usually exposed to adverse weather conditions, the effect of moisture and pollution on the characteristics is also investigated. Samples subjected to surface pollution were created according to the IEC standard under both wet and dry conditions. The collected electromagnetic signals were sampled and analyzed using a joint time-frequency analysis tool called the Wigner-Ville distribution (WVD). The results of this work indicate that the WVD analysis can be used as a diagnostic tool for polymer ZnO surge arrestors. Index Terms--Surge arrestor, surface pollution, electromagnetic pulse, Wigner distributions.

An ab initio quantum mechanical/molecular mechanical (QA/MM) molecular dynamics (MD) simulations was performed at an elevated temperature to study the temperature effects on the structural and dynamical properties of a Zn(II)-water complex in aqueous solution. Within the simulation time, no first shell was observed in the QM/MM simulation even at 90 degrees centigrade.

The 500-kV polymeric ZnO surge arresters for compact transmission line against lightning overvoltage were developed and have been put into operation, which consists of arrester unit and series gap. The design of the arrester unit, including structure design, selection of ZnO varistor, parameter determination, polymeric housing design, and mechanical structure design was discussed. The design of the series gap and the determination of the series gap length were presented. The calculated results state the line surge arrester can highly improve the lightning withstand level of the compact transmission line, and the line surge arrester can withstand the effects of lightning. Index Terms--Compact transmission line, lightning protection, lightning withstand level, line surge arrester, series gap.

Nanocrystals of Zn(sub (1-x))Mn(sub x)O were produced using a novel colloidal chemistry technique. The manganese ions primarily substitute zinc ions in the hexagonal ZnO lattice, and part of them are ferromagnetically coupled up to room temperature even in isolated noninteracting nanocrystals and the rest of ions are magnetically disordered or uncoupled and the study highlights the advantages of working with noninteracting single domain particles of these intriguing materials.