A lead-free ceramic with the composition (K0.55Na0.45)0.965Li0.035Nb0.80Ta0.20O3 was found having an outstanding piezoelectric performance. It possesses high properties of d33=262 pC/N, kp=0.53, k33=0.63, and k31=0.31 ε′=1290 tan δ=0.019 at room temperature. In spite orthorhombic-tetragonal polymorphic phase transition around 30 °C, temperature stability electromechanical coupling coefficients is very good over common usage interval between −40 85 °C. Furthermore, remain almost unchanged in...

Due to the orthorhombic-tetragonal polymorphic phase transition near room temperature, undesirable large temperature dependence of piezoelectric properties is observed over common usage range in BaTiO3 ceramics with high d33 values. Whereas shifting upward by partially substituting Ti Zr effective reducing dependence, serious long-term degradation occurs. However, it found that this could be overcome incorporating a small amount CuO additive. CuO-modified Ba(Ti0.9625Zr0.0375)O3 possess...

A good understanding of the strong piezoelectric mechanism BaTiO3 ceramics is very important from both scientific and technological viewpoints. This Letter reports an unusual phenomenon observed in a group large-grained dense with average grain sizes ranging 5.1 to 16.3 μm, which are prepared hydrothermally synthesized fine powder by hot-press sintering. Among these ceramics, one possessing size 5.6 μm exhibits particularly prominent piezoelectricity constants d33 = 485 pC/N d33* 725 pm/V at...

Abstract The prediction of the remaining useful life (RUL) widely used lithium-ion batteries (LIBs) is great importance. Existing techniques struggle to balance accuracy with execution time. To achieve accurate RUL quickly, a hybrid method for LIBs has been developed. This first employs channel-wise deep residual shrinkage network adaptively extract features from input data enhancing important information and suppressing ineffective ones based on significance feature information....

In order to reduce the sintering temperature and enhance piezoelectricity, a small amount of CuO was added into BaTiO3 during sintering. The aging behaviours these modified ceramics were studied systematically. For unpoled ceramic, P–E loop changes gradually from normal single-loop curve double-loop one with aging. Meanwhile, S–E develops strain almost zero under electric field below 10 kV mm–1. poled it builds much stronger more stable internal bias after loops shift significantly along...

The ab initio calculation and bond valence model (BVM) are employed to investigate dopant occupancy in the Ti-doped high-temperature phase Ta2O5. In this structure, there two types of Ta atoms, which authors denote as Ta1 locating inside oxygen octahedral Ta2 decahedral. 5d state electron configuration is different, hybridization between O 2p stronger than that O. chemical bonding ions mainly covalent. However, an increase covalent character going from Ta1–O Ta2–O bond. Both total energy...

CaCu 3 Ti 4 O 12 (CCTO) ceramics are prepared by the conventional solid-state reaction method under various sintering time conditions. Dielectric properties and complex impedance spectra investigated from room temperature up to 350°C. The high dielectric permittivity is found closely relate microstructure. High-temperature dispersion exhibits a large low-frequency response two Debye-like relaxations. There exist three semicircles in plane. observed electrical ascribed polycrystalline...

Abstract Gaze following aims to interpret human-scene interactions by predicting the person’s focal point of gaze. Prevailing approaches often adopt a two-stage framework, whereby multi-modality information is extracted in initial stage for gaze target prediction. Consequently, efficacy these methods highly depends on precision previous modality extraction. Others use single-modality approach with complex decoders, increasing network computational load. Inspired remarkable success...

The crystal structure and electronic properties of PbFe0.5Nb0.5O3 (PFN) are studied by full potential linearized augmented plane wave (FLAPW) method. optimized structure, density states band have been obtained to understand the ferroelectric behavior PFN. From analysis, it is shown that there hybridization Fe d − O p Nb in This consistent with calculation structure. responsible for tendency ferroelectricity.

In order to obtain both high piezoelectric property and good temperature stability in BaTiO 3 -based ceramics the common usage range, Sn 4+ Zr are co-doped into according formula of Ba ( Ti 0.96 x 0.04-x ) O (BTSZ) (x = 0.01–0.4) with 1 mol% CuO being added as sintering-aid this study. The -modified BTSZ show properties stability. Particularly, 0.01 0.03 ceramic displays d 33 350 pC/N, k p 49.5% at room-temperature a weak dependence range -15°C 60°C. Moreover, shows stable thermal aging...

ABSTRACT The pseudopotential methods have been employed to investigate the electronic structures of α and β-PHASE poly (vinylidene fluoride). In energy band structure PVDF, a large dispersion valence is found only along chain direction, which agrees well with angle-resolved photoemission experiments implies quasi-one-dimensional nature PVDF. LUOM caused by H s, C2 s p state mainly. exhibits anisotropy, while isotropy in -phase

The shape of hysteresis loop as well domain pattern ferroelectric during polarization reversal process has been simulated using Monte Carlo method on Ising model. Apart from the nearest-neighboring exchange interaction in model, we take into contributions third-neighboring interactions and four-body couplings. simulation is carried out a two-dimension square 200 × lattice with Metropolis sampling. A sinusoidal electric field applied to reverse get patterns. At low temperature, shows typical...

ABSTRACT A modified diffused limited aggregation model (mDLA) and Ising has been proposed on a two dimension 200 × 100 lattice for investigating the physical property in fatigued ferroelctric thin film. Firstly mDLA is used to generate dendritic pattern. Then spin-1/2 implemented represent dipole array films. Monte Carlo method employed simulations. Domain patterns as well hysteresis loop have obtained. It was found that polarization could be easily reversed around dendrite sites, which...

Achieving a high relativity density value in the (K,Na)NbO3 based ceramics is usually quite difficult due to volatility of alkali elements. A modified two-step sintering technique has been attempted conveniently fabricate dense through solid state reaction route this work. The chemical composition (K0·50Na0·50)NbO3 was chosen as test example. As result, obtained ceramic shows much improved microstructure with relative 97·1% and comparatively uniform grain size distribution, thus differs...

Abstract Review: 16 refs.

Abstract Monte Carlo investigations of the D∗ value for Ising strips D × L (D ≪ L) with periodic boundary conditions have been performed. The apparent critical temperature was determined by means Binder Cumulant Method crossing data 2L. results show that is 4.25 ± 0.05, i.e., T C (D) = 0 < 0.05 and TC (d 2) 2.269185 ≥ 0.05. ACKNOWLEDGMENTS work financially supported Natural Science Fund China under grant No.50702030 No.10474057. Communicated Dr. George W. Taylor