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The piezoelectric properties of SrBi4Ti4O15 and Bi4Ti2.95Nb0.04O12 have been compared as a function of applied ac stress. Evidence of domain-wall motion was observed in Bi4Ti2.95Nb0.04O12 but not in SrBi4Ti4O15. Examination of SrBi4Ti4O15 using transmissio ...
The piezoelectric properties of the bismuth titanate niobate Bi7Ti4NbO21 have been studied. The two phase transitions at 677 degrees and 856 degrees C are analyzed based on the measured piezoelectric properties. It is shown that the Bi7Ti4NbO21 compound is ...
Piezoelectric properties of Pb(Zr,Ti)O-3 thin films are investigated as a function of the number of bipolar (switching) and unipolar (nonswitching) voltage pulses. The longitudinal piezoelectric coefficient d(33) decreases with bipolar fatigue reflecting t ...
The behavior of alpha-quartz under hydrostatic and nonhydrostatic high-pressure conditions has been investigated in molecular dynamics simulations of silica in order to clarify the role of nonhydrostatic stresses in the amorphization process. It is shown t ...
The large piezoelectric effect of ferroelectric ceramics is utilized in many devices for sensing and actuating purposes. In this paper, the longitudinal direct piezoelectric effect in ceramics based on lead zirconate titanate, lead titanate, barium titanat ...
The influence of ultraviolet (UV) illumination on piezoelectric properties is investigated in lead zirconate titanate (PZT) thin films. It is found that the poling procedure is more effective when the film is exposed to a broadband UV light in the presence ...
Piezoelectric and dielectric aging was studied in Pb(Zr,Ti)O-3 (PZT) thin films and bulk ceramics. It was found that piezoelectric aging in thin films obeys the logarithmic time dependence with the relative aging rate much higher than that of the dielectri ...
Low-field piezoelectric coefficient and strain were investigated in Ca-modified PbTiO3 thin films by means of optical interferometry. A remanent piezoelectric coefficient of 70 pm/V was observed that agrees well with the values previously reported for the ...
Degradation of piezoelectric properties has been studied in ferroelectric PZT films by means of optical interferometry. The degradation under de bias and aging of poled films have been observed. The decay of piezoelectric coefficient with time is described ...
A reusable piezoelectric immunosensor has been developed for the detection of viruses and bacteria, playing an important role in acute diarrhea in early childhood. Three different methods for antibody immobilization to the gold electrode were tested. Coati ...