We investigate the effects of polytetrafluoroethylene PTFE on poly 3-hexylthiophene :phenylC61-butyric acid methyl ester P3HT:PCBM based organic photovoltaic OPV devices by inserting thermally evaporated PTFE films between indium-tin-oxide ITO and P3HT:PCBM layers. Significant improvement in terms of open-circuit voltage, short-circuit current, and thereby in its commensurate power conversion e...

This paper presents a simple method to fabricate micro-ball lens and its array. The key technology is to use the hydrophobic characteristics of polyterafluoroethylene (PTFE) substrate. High contact angle between melted photoresist pattern and PTFE can generate micro-ball lens and its array. PTFE thin film was spun onto a silicon wafer and dried in oven. Photoresist AZ4620 was used to pattern mi...

The primary removal of product water in proton exchange membrane (PEM) fuel cells is through the cathode gas diffusion layer (GDL) which necessitates the understanding of vapor and liquid transport of water through porous media. In this investigation, the effect of microporous layer (MPL) coatings, GDL thickness, and polytetrafluorethylene (PTFE) loading on the effective water vapor diffusion c...

The rheological characteristics of one mineral oil and two ionic liquid (IL) based lubricating greases were explored as a function of thickener concentration. The ILs used are 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([BMIM][TFSI]) and trihexyltetradecylphosphonium bis(trifluoromethylsulfonyl)imide ([P6,6,6,14][TFSI]), with polytetrafluoroethylene (PTFE) particles used as t...

The aim of the present study was to investigate the serum levels of 6-keto-prostaglandin (PG)F1α and thromboxane (TX)B2, as well as the endothelialization and hyperplasia of polytetrafluoroethylene (PTFE) and Dacron prostheses seeded with CD34+ cells in medium-term observation. A total of 24 crossbred dogs were randomly distributed into PTFE or Dacron groups. CD34+ cells were isolated from bone...

A review is given of the development of the concept of an artificial tympanic membrane. Starting with homologous tympanic membranes we compared biodegradable collagen materials (homologous and heterologous) and biodegradable synthetic materials, poly-glycolic acid, poly-lactic acid and poly-alpha-amino acids. As a non-degradable material microporous PTFE and bisphenol-A poly (carbonate) were in...

A new internet-based synchrotron experiment for students is presented. A polarimeter and computer software have been developed for measuring via the internet the X-ray magnetic circular dichroism of PtFe around its Pt L(II) and L(III) absorption edges. From the experiment, students can examine the X-ray magnetic circular dichroism of a thin PtFe foil utilizing circular-polarized synchrotron rad...

An analytic robust model is developed for estimating GDL thermal conductivity. The model considers PTFE addition to the GDL. Thermal conductivity of MPL is accurately measured in a compression range of 2e14 bar. Effect of thermal conductivity on PTFE, MPL, and compression is considered. Thermal contact resistances between GDL and MPL/iron surface are measured. a r t i c l e i n f o

In this work, a new framework and model for the digital generation and characterization of the microstructure of gas diffusion layer (GDL) materials with localized binder and polytetrafluoroethylene (PTFE) distributions were developed using 3D morphological imaging processing. This new generation technique closely mimics manufacturing processes and produces complete phase-differentiated (void, ...

The electrostatic charge on nylon, polypropylene (PP), and polytetrafluoroethylene (PTFE) after rubbing against stainless steel and against each other was examined using a newly developed rubbing device with automated features. It is observed that the charge generated on PTFE and PP increases as the contact force increases, while the charge generated on nylon is not affected by the contact forc...