The porosity and wettability properties of hydrogen ion treated polytetrafluoroethylene (PTFE) materials are related using contact angle, scanning electron microscopy (SEM), and ellipsometry tests. PTFE are irradiated using a low energy hydrogen ion shower (LEHIS) produced by a Gas Discharge Ion Source (GDIS). The plasma discharge current (Id) is varied at intervals of 1 mA. Results show that t...

This paper investigates the self-loosening of threaded fasteners subjected to dynamic shear load. Three kinds of typical coatings, PTFE, MoS2, and TiN applied to bolts and nuts, are tested in this investigation. The study experimentally examines the loosening mechanisms of fasteners and assesses the anti-loosening performance of the three tested coatings based on their tightening characteristic...

Through-plane thermal conductivity of 14 SIGRACET gas diffusion layers (GDLs), including series 24 & 34, as well as 25 & 35, are measured under different compressive pressures, ranging from 2 to 14 bar, at the temperature of around 60 ͦC. The effect of compression, PTFE loadings, and micro porous layer (MPL) on thermal conductivity of the GDLs and their contact resistance with an iron clamping s...

This study compared the effectiveness of 2 barrier membranes, expanded polytetrafluoroethylene (e-PTFE) and collagen, in treating Class II furcation defects of mandibular molars in humans. Seventeen nonsmoking subjects with no history of systemic disease each presenting with Class II furcation defects in 2 mandibular molars were selected and underwent initial therapy. At the time of the surgery...

Intimal hyperplasia is one of the prominent failure mechanisms for arteriovenous fistulas and arteriovenous access grafts. Human tissue-engineered vascular grafts (TEVGs) were implanted as arteriovenous grafts in a novel baboon model. Ultrasound was used to monitor flow rates and vascular diameters throughout the study. Intimal hyperplasia in the outflow vein of TEVGs was assessed at the anasto...

PTFE/GF(glass fiber) composites are widely applied in high-frequency printed circuit board (PCB) substrate materials due to the excellent dielectric properties of PTFE and low thermal expansion coefficient GF. However, poor interface compatibility between GF affects performance composite substrates. In this study, tetraethyl orthosilicate (TEOS) was used as silicon source, polydimethylsiloxane ...

Optical waveguide lightmode spectroscopic (OWLS) techniques were probed for monitoring ion permeation through channels incorporated into artificial lipid environment. A novel sensor set-up was developed by depositing liposomes or cell-derived membrane fragments onto hydrophilic polytetrafluoroethylene (PTFE) membrane. The fibrous material of PTFE membrane could entrap lipoid vesicles and the wa...

The chemical inertness, high melting point, and intrinsic lubricity of polytetrafluoroethylene PTFE have been used to develop solid lubricating parts for operation in extreme environments, from frying pans to satellites. The atomic-level mechanisms associated with friction and wear at PTFE surfaces are elucidated here by systematic investigations of the frictional anisotropy measured with respe...

We report the successful treatment of a patient with hemifacial spasm due to a tortuous vertebral artery that appeared to have developed to compensate for agenesis of the ipsilateral carotid artery. The 51-year-old man presented with a 1-year history of progressive left hemifacial spasm. His medical history was otherwise unremarkable except for untreated mild hypertension. Magnetic resonance an...