This paper presents a micro-electro-mechanical system (MEMS) piezoelectric power generator array for vibration energy harvesting. A complete design flow of the vibration-based harvester using finite element method (FEM) is proposed. The modal analysis selected to calculate resonant frequency harvester, and harmonic performed investigate influence geometric parameters on output voltage. Based simulation results, MEMS Pb(Zr,Ti)O3 (PZT) cantilever with an integrated large Si proof mass designed...

We report an effective strategy to enhance the localized surface plasmon resonances (LSPRs) of metallic nanoparticles by introducing a Fabry-Pérot (FP) cavity for high-quality sensing. The concept is based on combined excitation LSPRs in and optical modes supported FP cavities, whose strong interactions result two ultra-narrowband hybridized with huge electric field enhancement. A double-band plasmonic nanosensor, refractive index sensitivity approaching 600 nm/RIU figure merit exceeding 28...

Abstract In the process of drilling with water‐based fluid, polymer plugging agent is very important to solve problem wellbore instability in formation micropores and microfractures. this study, N ‐isopropyl acrylamide 2‐acrylamide‐2‐methylpropanesulfonic acid were grafted onto surface SiO 2 modified by vinyl trimethoxysilane reverse suspension polymerization reaction, a heat‐sensitive was synthesized. The structure analysis showed that synthetic material target product, particle size 49.665...

The voltage output of PZT thin film microelectromechanical system (MEMS) vibration energy harvester in d <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">31</sub> mode is usually <;1 V at present. In practical applications, rectifier circuit often utilized after harvester. So the low will cause most power loss circuit. To solve this problem while ensuring high output, a MEMS with designed and fabricated. proposed consists five cantilevers one...

Piezoelectric vibration energy harvesting has attracted increasing attention in the last decade, and one of major challenges is concerning design these harvesters. Most researchers optimize piezoelectric harvester at constant excitation acceleration. However, practical applications, allowable stress cantilevered limits maximum displacement cantilever. Thus, both cantilever acceleration should be considered when optimized. In this article, damping ratio electromechanical coefficient are...

An enhanced quarter-spherical acoustic energy harvester (AEH) with dual Helmholtz resonators was designed in this work. Compared the previous research, AEH can harvest multi-directional energy, has a widened resonance frequency band, and an improved conversion efficiency. When length of resonator’s neck is changed, resonant two different. The theoretical models output voltage power were studied, relationship performance obtained. results showed that operate efficiently band about 470 Hz. Its...

Abstract Lost circulation will cause huge economic losses every year. In order to effectively reduce the harm of lost drilling, it is particularly important use reasonable and efficient materials (LCM). As a kind water‐absorbing, expandable deformable LCM, water‐absorbing resin can adapt holes cracks different sizes. this study, encapsulated LCM (PMMA/PNAD) was proposed. The synthesized by acrylamide (AM), 2‐acrylamide‐2‐methyl‐propane sulfonic acid (APMS) diallyl dimethyl ammonium chloride...

In this work, a novel 3-D equivalent circuit model of thermoelectric microelectro-mechanical system (MEMS) microwave power sensor is proposed. According to the model, temperature distribution and response time MEMS are obtained. The designed fabricated based on GaAs monolithic integrated (MMIC) technology. measured results show that sensitivity 0.06 mV/mW at 10 GHz constant 85 μs. theoretical 0.076 56.24 relatively consistent with results. Furthermore, heat dissipation in substrate can be...

Non-heme mononuclear iron complexes, especially when supported by tripodal tetradentate ligands, show promising C-H bond activation efficiency in catalytic reactions. Nevertheless, they intrinsically decay readily to their dinuclear form, and the dimerization process is inevitable homogenous solution, which dramatically hinders further application. Hence, we demonstrate that complex [(TPA)FeII-2L]2+ (L = labile mainly solvent molecules) was successfully encapsulated a highly robust...

An H-shaped piezoelectric vibration energy harvester (VEH) with two dimensional receiving direction is designed to provide power for engine fault monitoring in this work. The VEH consist of one main-beam which receives the vibrational excitation horizontal direction, and sub-beams receive vertical direction. sub-beam are almost independent. So could be modelled as a lumped-mass model. models output voltage given. fabricated using computer numerical control technology. measured results show...

Tire pressure monitoring system (TPMS) is used to detect the tire pressure, temperature and many other parameters in real time. At present, most of these systems are powered by button batteries, which cannot last entire lifetime device periodic replacement or recharging tedious. As a promising alternative method for harvesting energy from vibration has attracted widespread attention recent years. In this paper, research progress collection TPMS application reviewed. Three transduction...

Adding nanoparticles in a drilling fluid can aid the sealing of nanopores borehole wall rock and mud cake; this way, filtrate loss be reduced is stabilized.In work, spectrophotometric method was used to study effect dispersants on calcium carbonate nanoparticles.The best dispersion achieved at cetyltrimethyl ammonium bromide (CTAB) concentration 4 wt.%,dispersing time 45 min, pH value 8 stirring speed 900 rpm.The structure analysis showed that adsorption layer formed surface after CTAB...

A nonlinear thermodynamic formalism is developed to calculate the pyroelectric property of epitaxial single domain [Formula: see text] heterojunctions by taking into account thermal expansion misfit strain at different temperatures. It has been demonstrated that crucial role was played contribution associated with structure order parameter arising from rotations oxygen octahedral on pyroelectricity. dramatic decrease in coefficient due strong coupling between polarization and found...