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Showing 1 to 20 of 54 for “"polyvinylidene fluoride"”.
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Design and Fabrication of Polyvinylidene Fluoride for Triboelectric Nanogenerators
… is needed. Herein, effects of polyvinylidene fluoride (PVDF) friction layers thickness, contact area and porosity on TENGs performance were investigated. Results showed that increasing surface area or decreasing thickness of friction layer positively affected the performance of …
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Characterization of Nanoporous Polyvinylidene Fluoride (PVDF) Sensors under Tensile Loading
… To improve the material’s piezoelectricity, a Polyvinylidene Fluoride (PVDF) sensor with integrating nanoporous structures was developed and fabricated. Several sets of samples with different porosities from 0% to 42.0% were made. The porosity effect on the sensor samples was studied under …
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Detection of in-plane stress waves with Polyvinylidene Fluoride (PVDF) sensors
<p>Polyvinylidene Fluoride (PVDF), a piezoelectric polymer, is an excellent stress sensor. The objective of this research is to investigate the application of the PVDF sensors for detection of in-plane stress waves in 31 and 32 modes. This was achieved by focusing on aspects of PVDF sensing related …
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Characterization of Surfactant Effects on the Visible Spectroscopy of Lanthanide Metal Ion-Triphenylmethane Dye Complexes (Microscopy, Polyvinylidene Fluoride, Electron, Polymethylmethacrylate, Blends)
Although both micellar and submicellar concentrations were considered, adding the nonionic surfactant Triton X-100 to the Gd('+3)-CAS complex had little effect.
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Structure and Property of Polybutylene, Polypropylene and Polyvinylidene Fluoride Crystallized From the Glassy State and Structure-Property - Processing Relationships of Polypropylene - Polybutylene Blends
… glassy polybutylene (PB), polypropylene (PP) and polyvinylidene fluoride (PVF(,2)). The structure and properties of the as-quenched and subsequently crystallized samples were characterized by various techniques. The glass has no structure larger than 30 (ANGSTROM). PB crystallizes from the glass …
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Aircraft interior acoustic noise control
… reduction properties, weight, and thickness. Polyvinylidene Fluoride was tested for use in active noise control for a large space.
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Preparation of Polymer Composites As Dielectric Materials For Capacitors
… properties compared to the neat polymers. Polyvinylidene fluoride (PVDF) based ferroelectric polymers are mainly used for energy storage. And CaCu3Ti4O12 (CCTO) is still a novel dielectric ceramic oxide with giant dielectric permittivity. This research project combines P(VDF-HFP) and nano …
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An electromechanical system for characterization of piezoelectric materials
… Two well-known piezoelectric materials, Polyvinylidene Fluoride (PVDF) and Lead Zirconate Titanate (PZT), are used as samples in this project to demonstrate the device operation. In addition, a non-piezoelectric material is included as a control group.
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The use of thin polymeric coatings to prevent fretting corrosion and metallic contact in steel-on-steel systems
… polytetrafluoroethylene (PTFE), polyimide (PI), polyvinylidene fluoride (PVDF), polyvinylidene chloride (PVDC), polyvinyl chloride (PVC), low-density polyethylene (LOPE), high-density polyethylene (HDPE), polysulfone (PSO) and polystyrene (PS). These polymers were applied as thin films to a steel …
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LOW-DIMENSIONAL CHALCOGENIDE BASED THERMOELECTRIC COMPOSITES
… we further combine them with polymers such as polyvinylidene fluoride to guarantee their flexibility in thermoelectric devices. Here, the non-conductive polymer can not only guarantee the robustness and flexibility but also create a high trap-state by introducing the energy barrier at the …
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Hollow fiber membrane-based air gap membrane distillation
… fiber sets separately: porous hydrophobic polyvinylidene fluoride hollow fibers of the E type (PVDF E) and solid polypropylene (PP) hollow fibers. Vapor from the hot brine crosses the membrane pores of the PVDF fibers and the air gap, and finally condenses over the surface of solid hollow …
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Effects of Multi-walled Carbon Nanotubes (MWCNTs) and Integrated MWCNTs/SiO2 Additives on Polymeric PVDF Membrane for Membrane Distillation
… were loaded as additives into nanocomposite polyvinylidene fluoride (PVDF) membranes fabricated via phase inversion methods, and the effects of these additives on the structure and vacuum membrane distillation (VMD) performance of the membranes have been studied. With an appropriate amount of …
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STRUCTURE AND PROPERTIES OF PIEZOELECTRIC NANOFIBERS FOR ELECTROMECHANICAL COUPLING APPLICATIONS
… for electromechanical coupling applications. Polyvinylidene fluoride (PVDF) nanofibers were fabricated by electrospinning process using a precursor solution modified with hydrated salt. Introducing hydrated salts in PVDF precursor solution proves very effective in improving the polar β-phase …
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Advanced sensing techniques for active structural acoustic control
… distributed structural sensors constructed from polyvinylidene fluoride (PVDF), distributed acoustic near-field sensors constructed from PVDF, and accelerometers were explored as alternatives to microphones which are typically implemented as error sensors in the cost function of the control …
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A New Adaptive Array of Vibration Sensors
… is done with an array of piezoelectric polyvinylidene fluoride (PVDF) film segments on a beam to obtain the segment outputs. The results from the experiment are used to verify a computer simulation routine. Then a series of simulations are done to test the adaptive modal sensing …
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Modeling a piezoelectric flag as a membrane for energy harvesting
… this case, due to its inherent flexibility, is polyvinylidene fluoride (PVDF). This is a rapidly expanding area of study. Most notably, energy harvested from vortex-induced vibrations, along with bluff bodies, is of particular interest. After the literature review concerning piezoelectric …
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Caracterização do efeito whitening em polifluoreto de vinilideno (PVDF) por ensaio ultrassônico
… and quantitatively the whitening effect of polyvinylidene fluoride (PVDF) samples using the ultrasound test. Therefore, the techniques which used were the measurements of sonic velocity, spectral Fourier analysis, second order moment, Hurst analysis (R / S) and dentreded fluctutation …
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A Distributed Active Vibration Absorber (DAVA) for Active-Passive Vibration and Sound Radiation Control
… is constructed from the piezoelectric material polyvinylidene fluoride (PVDF) and thin layers of lead. The tested device is designed to weight less than 10% of the main structure and has a resonance frequency around 1000 Hz. Experiments have been conducted on a simply supported steal beam …
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