Objectives • Elucidate rates and mechanisms of the degradation of polymer electrolyte fuel cell (PEFC) platinum electrode performance – Effect of electrolyte, potential (holding and cycling), time, and temperature • Develop non-platinum cathode electrocatalysts for PEFCs – Transition metal carbides and nitrides – Bi-metallic systems – Metal centers attached to electron-conducting polymer backbones

A UV-responsive polymer was prepared via condensation polymerization of 2-nitrobenzyl(4-(1,2-dihydroxyethyl)phenyl)carbamate and azalaic acid dichloride. When the polymer was irradiated with UV light, the nitrobenzyl urethane protecting group was removed and the deprotected aniline underwent spontaneous 1,6-elimination reactions, resulting in degradation of the polymer. Nanoparticles with encap...

Magnesium and its alloys may potentially be applied as degradable metallic materials in orthopaedic implantations due to their degradability and resemblance to human cortical bone. However, the high corrosion rate and accumulation of hydrogen gas upon degradation hinders its clinical application. In this study, we adopt a new approach to control the corrosion rate by coating a controllable poly...

Polymeric film coatings were applied by dip coating on two magnesium alloy systems, AZ31 and Mg4Y, in an attempt to slow the degradation of these alloys under in vitro conditions. Poly(lactic-co-glycolic acid) polymer in solution was explored at various concentrations, yielding coatings of varying thicknesses on the alloy substrates. Electrochemical corrosion studies indicate that the coatings ...

There is an acknowledged need for improved conservation of plastic and rubber objects within collections, including improved methods of condition assessment, material identification, and better understanding of material degradation. This reflects the inherent instability and wide-ranging formulations of many such objects and also the relative lack of knowledge in this field. Analysis of volatil...

INTRODUCTION 6.3 million cases of bone trauma happen each year in the US alone [1]. In a majority of these cases, permanent fixation implants using titanium plates and screws are used as a remedy, but they do have their drawbacks. Some of these disadvantages include bone wear and degradation, resulting in the implant to become loose. They also present a prime site for possible infection [2]. An...

the principal effects of mass degradation on polymer matrix composites (pmcs) are the decay of mechanical properties such as strength, elongation, and resilience. this degradation is a common problem of the pmcs under thermal cycling conditions. in this article, composite degradation was investigated by measurement of total mass loss (tml) using the taguchi approach. thermal cycling tests were ...

Silver nanostructures as an effective antibacterial materials were synthesized via three various hydrothermal, sono-chemical and microwave methods using water as a green solvent. Then Chitosan-Ag polymer based nanocomposites were made by a fast chemical procedure. The influence of power, temperature and time on the morphology and particle size of the products was investigated. Scanning electron...

Electron microscopy has been used to study the degradation of organic solar cells when exposed to humid air. Devices with various different combinations of commonly used organic solar cell hole transport layers and cathode materials have been investigated. In this way the ingress of water and the effect it has on devices could be studied. It was found that calcium and aluminum in the cathode bo...

A multifunctional Cu(I) coordination polymer constructed from helical chains showed unusual mechanochromic, sensing of nitrobenzene and photocatalytic properties on degradation of organic dyes.