DETERMINATION OF BASIC CHARACTERISTICS OF PROTECTIVE LAYERS BASED ON POLYMERIC NANOFIBERS
This work focuses on a basic research in developing new class of protective layers for building materials based on polymeric nanofibers. Nonwoven nanotextiles are fibers with diameter spanned from tens to hundreds of nanometers. Thin films consisting of suitable polymer-based nanofibers were prepared using NANOSPIDER equipment. Applied technology is unable to fully guarantee quality (homogeneity, thickness, etc.) of the protective coating. Traditionally used technologies –such as painting or spraying – are not too effective and the separation of protective coating or loosing of protective properties is frequently observed.
Electrospun SiO2 Nanotextiles for Preservation of a Tangible Cultural Heritage
The developing nanotechnology is getting infiltrated into a wide area of industries. A variety of nanotextiles can be produced from different materials (e.g. polymers, SiO2). Their applications are possible in many industrial branches as well as civil engineering. Silica-based nanotextiles can play a fundamental role in civil engineering. The potential utilization of nanotextiles in civil engineering is promising as surface protective layers. Wettability of SiO2 nanotextiles was studied on different thicknesses of samples and were tested under static conditions by determination of the water contact angle. Their water contact angle, which indicates the degree of wetting, was measured using an optical tensiometer.
A Critical Assessment on Functional Attributes and Degradation Mechanism of Membrane Electrode Assembly Components in Direct Methanol Fuel Cells
Direct methanol fuel cells (DMFC) are typically a subset of polymer electrolyte membrane fuel cells (PEMFC) that possess benefits such as fuel flexibility, reduction in plant balance, and benign operation. Due to their benefits, DMFCs could play a substantial role in the future, specifically in replacing Li-ion batteries for portable and military applications. However, the critical concern with DMFCs is the degradation and inadequate reliability that affect the overall value chain and can potentially impede the commercialization of DMFCs. As a consequence, a reliability assessment can provide more insight into a DMFC component’s attributes. The membrane electrode assembly (MEA) is the integral component of the DMFC stack. A comprehensive understanding of its functional attributes and degradation mechanism plays a significant role in its commercialization. The methanol crossover through the membrane, carbon monoxide poisoning, high anode polarization by methanol oxidation, and operating parameters such as temperature, humidity, and others are significant contributions to MEA degradation. In addition, inadequate reliability of the MEA impacts the failure mechanism of DMFC, resulting in poor efficiency. Consequently, this paper provides a comprehensive assessment of several factors leading to the MEA degradation mechanism in order to develop a holistic understanding.