In this paper, a novel aluminum nitride (AlN) resonant pressure sensor with piezoelectric-excitation and piezoelectric-detection is presented. The key structure of resonator an AlN flexible beam. Parallel electrodes are designed on the beam to excite resonance in-plane. All layers grown silicon-on-insulator (SOI) wafer by deposition process. Anchor islands fabricated in top silicon layer SOI. o...

Some new 3-(alkylsulfanyl)- 7-chloro-1-phenyl-1H-pyridazino [4,3-e][1,3,4]thiadiazine were synthesized  by treatment of the alkyl-2-phenylhydrazinecarbodithioates with 4-bromo-3,6-dichloropyridazine in alkaline acetonitril. Orientation of the reaction has been determined by X-Ray crystallography technique. The chlorine atom on the number 7 position of these products was replaced by secondary am...

abstract: the main aim of the vibration energy harvesters is to locally power autonomous devices such as wireless sensors. generally, power levels are low and the environmental benefit of the technology is to replace batteries rather than saving energy per se. piezoelectric vibrational energy harvesters are usually inertial mass based devices, where a cantilever beam with a piezoelectric outer ...

X-ray crystallography unequivocally confirmed the stereochemistry of the 2-C-methyl group in the title mol-ecule, C(10)H(16)O(6), in which the 1,5-lactone ring exists in a boat conformation. The use of d-galactose in the synthesis determined the absolute stereochemistry. The crystal exists as O-H⋯O hydrogen-bonded layers in the ab plane, with each mol-ecule acting as a donor and acceptor for tw...

The present work considers the active vibration control of beam like structures with laminated piezoelectric sensor and actuator layers bonded on top and bottom surfaces of the beam. A finite element model based on Euler-Bernoulli beam theory has been developed. The contribution of the piezoelectric sensor and actuator layers on the mass and stiffness of the beam has been considered with modeli...

The application of various layers on a piezoelectric substrate is a way of improving the parameters of propagating electroacoustic waves. For example, a metal film of certain thickness may provide the thermal stability of the wave for substrate cuts, corresponding to a high electromechanical coupling coefficient. The overlayer can vary the wave propagation velocity and, hence, the operating fre...

Modal control and spatial filtering technologies for vibration and/or structural acoustics radiation mitigation may be implemented through the use of distributed modal piezoelectric transducers with properly shaped electrodes which, in order to increase the robustness and stability of the controlled structural system, turn undesirable mode’s contributions unobservable and uncontrollable over th...

Although lead-free piezoelectric ceramics have been extensively studied, many problems must still be overcome before they are suitable for practical use. One of the main problems is fabricating a multilayer structure, and one solution attracting growing interest is the use of lead-free multilayer piezoelectric ceramics. The paper reviews work that has been done by the authors on lead-free alkal...

Energy harvesting from surrounding environment has been attractive for many researchers in recent years. Therefore, developing appropriate test apparatus to study energy harvesting mechanisms and their performance is of paramount importance. Due to their electromechanical characteristics, piezoelectric materials are used for harvesting energy from environmental vibrations. For optimum utili...