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At present, coal mine tunneling technology is developing in the direction of intelligence and unmanned. The piezoelectric vibration energy harvester can convert the vibration energy generated by the cutting part of roadheader into electrical energy and realize the energy self-sufficiency of the low-power wireless sensor. In practical applications, the vibration frequency of the cutting part of roadheader is different, and the working condition is complex, resulting in the energy recovery efficiency of the vibration energy harvester is not ideal. In order to improve its adaptability and reliability, a separated excitation broadband piezoelectric vibration energy harvester is proposed in this paper. [ABSTRACT FROM AUTHOR]

To find out the effect of the rare earth doping element Holmium (Ho) on CuInS2 thin films, various studies have been carried out and the results have been reported in this paper. The PL study shows that intensity of doped film is more than undoped film. The PL emission peak appears at 570–580 nm. SEM images of CIS:Ho (4 ml) film shows agglomeration on the surface. Both synthesized film of CuInS2 appears to be amorphous in nature with chalcopyrite structure as clear from XRD. Hall measurement and optical studies were also performed. [ABSTRACT FROM AUTHOR]

In this paper, a composite excitation method is used to optimize the design of an existing cantilevered cylindrical ultrasonic motor to avoid vibration interference. Modal and transient simulation analysis of the stator structure was carried out by the finite element method. Optimized stator structure is simpler than the original motor. Simulation analysis results show that the circumferential amplitude is increased by more than 35% with 55.7% reduction in ceramic usage. [ABSTRACT FROM AUTHOR]

At present, coal mine tunneling technology is developing in the direction of intelligence and unmanned. The piezoelectric vibration energy harvester can convert the vibration energy generated by the cutting part of roadheader into electrical energy and realize the energy self-sufficiency of the low-power wireless sensor. In practical applications, the vibration frequency of the cutting part of roadheader is different, and the working condition is complex, resulting in the energy recovery efficiency of the vibration energy harvester is not ideal. In order to improve its adaptability and reliability, a separated excitation broadband piezoelectric vibration energy harvester is proposed in this paper. [ABSTRACT FROM AUTHOR]

To find out the effect of the rare earth doping element Holmium (Ho) on CuInS2 thin films, various studies have been carried out and the results have been reported in this paper. The PL study shows that intensity of doped film is more than undoped film. The PL emission peak appears at 570–580 nm. SEM images of CIS:Ho (4 ml) film shows agglomeration on the surface. Both synthesized film of CuInS2 appears to be amorphous in nature with chalcopyrite structure as clear from XRD. Hall measurement and optical studies were also performed. [ABSTRACT FROM AUTHOR]

Rare earth yttrium substituted lithium ferrites Li0.5Zn0.1Ti0.1YxFe2.3–xO4 with nominal composition x = 0.00 to 0.10 in steps of 0.02 was prepared by the conventional ceramic method. The samples were sintered at 1050 °C for 6 h using resistive conventional heating. X-ray diffraction (XRD) patterns confirmed the formation of a single phase with a spinel structure. FTIR studies also confirmed the tetrahedral and octahedral metal-oxygen bonding of the spinel structure. Structural parameters like density, lattice constant, and crystallite size, site distances, bond length distances were measured from XRD data. The crystallite size reduces while the density increased with the progressive substitution of Y3+ ions. The Fe3+ ions at the A and the B sites mainly contributes to the electromagnetic properties of ferrites. Y3+ ions preferably entering the B sites can significantly interfere with the conduction mechanism of lithium ferrites. The objective of the present work is to find out the effect of Y3+ substitution on the structural and electrical conduction response Li-Zn-Ti ferrites. The DC resistivity initially is found to increase for concentration x = 0.04 and then decrease with further substitution. The study of the temperature dependence of DC resistivity depicts two types of conduction mechanisms in the range studied. The results obtained are analyzed and presented in the paper. [ABSTRACT FROM AUTHOR]

Potassium sodium niobate (KNN) is an environmentally compatible piezoelectric material for substituting harmful lead-based ceramics. KNN-based ceramics have excellent piezoelectric properties with high Curie temperature. But, KNN faces difficulties during the processing like volatilization of alkali elements, chemical inhomogeneity, low densification, etc. The objective of this research is to investigate the impact of certain metal oxides additions like ZnO and MnO2 as sintering aids to solve the problems of the preparation and hence study the structural and electric properties of K0.5N0.5NbO3 (KNN) ceramics. ZnO and MnO2 added potassium sodium niobate, K0.5N0.5NbO3 was prepared by using the ceramic method. The prepared samples were sintered at 1000 °C for 2h conventionally. The structural properties of the ceramics have been analyzed by using X-Ray Diffractometer. The study demonstrates the formation of the orthorhombic-symmetric perovskite phase in all the prepared samples. The microstructural behavior of the ceramics has been characterized by techniques such as scanning electron microscopy (SEM) and compositional properties were studied by energy dispersive x-ray (EDAX). The effects of metal oxide additions on the electronic properties such as dielectric constant, dielectric loss, impedance properties, Nyquist plot, etc., were studied. The results have been analyzed and discussed in the paper. [ABSTRACT FROM AUTHOR]

Through a typical solid-state reaction followed by planetary ball milling, ABO3 structured perovskite Bi0.5Na0.5ZrO3 (BNZ) was employed as an additive to create the lead-free piezoceramic composite having compositional formula K0.47Na0.47Li0.06NbO3+(x)Bi0.5Na0.5ZrO3 where x = 0.0 wt% to 0.5 wt%. The prepared composites were characterized with the help of XRD, SEM, and FTIR. The XRD results indicated manifestation of morphotropic phase boundary (MPB), i.e. orthorhombic-tetragonal (O-T) phase boundary, for 0.4 wt% and 0.5 wt%. The SEM pictures revealed the microstructural properties of grain-grain size distribution and the average grain size of the composites. The elemental composition examination using EDAX revealed no foreign element contamination. The FTIR examination verified the development of perovskite, indicating that the BNZ has correctly fused into the KNLN matrix. The DC resistivity (ρdc) behavior was determined from IV and IR curves measured at room temperature together with varied temperature line up from 30 °C to 150 °C and a high dc resistivity ρdc of order ≈ 109 Ω cm was obtained for all the ceramics. The results have been analyzed and the mechanism pertaining to the results has been discussed in the paper. Thus the main idea was to develop a lead-free piezoceramic composite by incorporating Bi0.5Na0.5ZrO3 as an additive and investigating its effect on the above mentioned properties of the composite material. [ABSTRACT FROM AUTHOR]

In this paper, detailed studies of effect of small amount of manganese substitution (at the zirconium site) on the structural, micro-structural, and electrical characteristics of lead zirconate titanate of Pb(Zr0.35–xMnxTi0.65)O3;x = 0, 0.02, 0.06, 0.10 (PZMT)) have been reported. The materials were prepared by using standard ceramic technology. The formation of the compounds and their basic crystal data have been studied through X-ray diffraction (XRD) method. The crystallite size and lattice strain of the compounds, evaluated from Scherrer's and Hall Williamson (H-W) equations, is found to be in the range of 40–50 nm and 11 × 10−4 to 50 × 10−4, respectively. Microstructures of different magnifications, revealing the surface nature of the compounds, have been recorded by field emission scanning electron microscope (FESEM). Effect of Mn+4 ions on electrical behavior (electrical impedance (Z*), electrical modulus (M*), conduction and relaxation phenomenon) of PZMT systems, over wide range of temperature and frequency, has been studied. [ABSTRACT FROM AUTHOR]