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Showing 1 to 20 of 36 for “"Polyvinylidene fluoride (PVDF)"”.
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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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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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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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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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PVDF-graphene conductive composite membrane and PVA-graphene conductive composite membrane preparation and application
… of conductive membrane. In this research, polyvinylidene fluoride (PVDF) and polyvinyl alcohol (PVA) were used together with graphene to create graphene based polymer composite conductive membrane. First, Boehm titration was used to determine the linkage of carboxyl groups on the surface of …
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Mechanisms of MS2 bacteriophage removal by ultrafiltration membrane with different foulants
An ultrafiltration unit with a polyvinylidene fluoride (PVDF) membrane of 40 nm nominal pore size was used to study bacteriophage MS2 removal under different membrane conditions. The membrane conditions were subject to fouling of soluble microbial products (SMP), which was extracted from membrane …
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Active control of broadband acoustic radiation from structures
… actuators (PZT). Both far-field microphones and polyvinylidene fluoride (PVDF) structural sensors designed to optimally control the efficient acoustic radiating modes were used as error sensors. The disturbance was band-limited zero mean white noise and was input with a point force shaker. In the …
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Study on Structure and Vacuum Membrane Distillation Performance of PVDF Composite Membranes: Influence of Molecular Weight and Blending
In this study, membranes were made from three polyvinylidene fluoride (PVDF) polymers individually and the blend systems of high (H) and low (L) molecular weight PVDF by phase inversion process. After investigating membrane casting solutions’ viscous and thermodynamic properties, the membranes so …
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Flexible Strain Detection Using Surface Acoustic Waves: Fabrication and Tests
… substrate fabrication using hot-press made of polyvinylidene fluoride (PVDF) as a polymer matrix, with lead zirconate titanate (PZT), calcium copper titanate (CCTO), and carbon nanotubes (CNTs) as micro and nanofillers’ structural, thermal and electrical properties are investigated. …
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Reverse-Selective Behavior Of The Room Temperature Ionic Liquid Based Membranes
… of the above-mentioned gases was obtained using polyvinylidene fluoride (PVDF) as the support and [emim][Tf2N], [emim][BF4], [emim][TfO], [emim][DCA], [emim][SCN], and [bmim][NO3] as immobilized room temperature ionic liquid (RTIL). The results shothat permeance of carbon dioxide was the highest …
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