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Conventional Fibers (conventional + fiber)

Distribution by Scientific Domains
Polymers and Materials Science60%

Selected Abstracts

Influence of carbon nanotube dispersion on the mechanical properties of phenolic resin composites

POLYMER COMPOSITES, Issue 2 2010
R.B. Mathur
Despite the much touted mechanical properties of carbon nanotubes, composites reinforced with nanotubes have failed to achieve mechanical properties which rival those present in conventional fiber reinforced polymer composites. This article describes an attempt to bridge this gap. Multi-walled carbon nanotubes (MWCNT) were synthesized using a chemical vapor deposition method and were dispersed in phenolic resin by both the wet and dry dispersion techniques before molding into composite bars (50 × 5 × 3 mm3). Although no improvement in the mechanical properties of the MWCNT/phenolic composites was observed over the neat resin value when wet mixing dispersion was employed, an improvement of nearly 158% (160 MPa as compared with 62 MPa for neat resin) was achieved in 5 vol% MWCNT containing phenolic resin prepared by the dry mixing. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers [source]

Photonic Crystal Fibers and Their Applications

IEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING, Issue 6 2009
Osamu Tohyama Member
Abstract Dramatic advances in research and development on photonic crystal fibers (PCF) have created new properties that had not been achievable using conventional fibers. PCFs have many fascinating features. The very high relative refractive index between the fiber core and air-hole cladding enables several prominent properties, notably endlessly single-mode (ESM) operation, high nonlinearity, wide-ranging dispersion management, and the ability to maintain high polarization. The processes involved in manufacturing PCFs are quite different from those used to manufacture conventional fibers, and this is largely because of the profusion of air holes in the silica glass that comprises PCFs. The authors have optimized the technology to manufacture photonic crystals with the required optical characteristics. This paper describes the properties and application of large-mode and ESM guidance, nonlinearity, and double cladding. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [source]

Ultra-large effective-area, higher-order mode fibers: a new strategy for high-power lasers

LASER & PHOTONICS REVIEWS, Issue 6 2008
S. Ramachandran
Abstract This paper describes the physics and properties of a novel optical fiber that would be attractive for building high-power fiber lasers and amplifiers. Instead of propagating light in the fundamental, Gaussian-shaped mode, we describe a fiber in which the signal is forced to travel in a single, desired higher order mode (HOM). This provides for several advantages over the conventional approach, ranging from significantly higher ability to scale mode areas (and hence laser powers) to managing dispersion for ultra-short pulses , a capability that is practically nonexistent in conventional fibers. Particularly interesting is the fact that this approach challenges conventional wisdom, and demonstrates that for applications requiring meter-length fibers (as in high-power lasers), signal stability actually increases with mode order. Using this approach, we demonstrate mode areas exceeding 3200 ,m2, and propagate signals with negligible mode distortions over up to 50-meter lengths. We describe several pulse propagation experiments in which we test the nonlinear response of this fiber platform, ranging from managing dispersive effects in femtosecond pulse systems, to reducing Brillouin scattering impairments in systems operating with the nanosecond pulses. [source]

Enhanced Mechanical Performance of Self-Bundled Electrospun Fiber Yarns via Post-Treatments

MACROMOLECULAR RAPID COMMUNICATIONS, Issue 10 2008
Xuefen Wang
Abstract A new route to high-performance electrospun polymer fibers was developed using a self-bundling electrospinning technique combined with post-treatments such as stretching and annealing under conditions similar to those used for conventional fibers. Self-bundled electrospun PAN fiber yarns were characterized by SEM, mechanical tests, polarized FT-IR spectroscopy and WAXD. The obtained results revealed that the PAN nanofiber yarns possessed enhanced alignment, a higher degree of crystallinity and higher molecular orientation after treatments, resulting in a remarkable improvement in mechanical performance, approaching the strength value of the corresponding conventional fibers. [source]