A review on tribological behaviour of polymeric composites and future reinforcements

Many different families of polymers are used in industries and engineering applications. The demands for studying the tribological behaviour of polymers and their composites are recently increased. This article briefs the most recent studies on the tribological behaviour of polymeric materials based on synthetic fibres. It reviews several factors which control the wear and frictional characteristics of such materials, that is, additives, fibres, interfacial adhesion, tribology environment, operating parameters, and composite geometry. In addition to that, new bioreinforcement (fibre) is introduced associated with preliminary results. The results showed that there is high potential of replacing the conventional reinforcement with the bioones

Evolution of stars with suppressed core convection

Stellar evolution on the upper main sequence was computed for models of stars with cores assumed to be in radiative equilibrium, up to the point of central helium ignition. The role of the Schonberg-Chandrasekhar limit for an isothermal core is found to be critical for the evolutionary tracks. Observational data are used to rule out the hypothesis of evolution with radiative cores (in upper main-sequence stars) and, by implication, of magnetic fields that are sufficiently strong to have suppressed the core convention

Speech intelligibility and prosody production in children with cochlear implants

Objectives—The purpose of the current study was to examine the relation between speech intelligibility and prosody production in children who use cochlear implants. Methods—The Beginner\u27s Intelligibility Test (BIT) and Prosodic Utterance Production (PUP) task were administered to 15 children who use cochlear implants and 10 children with normal hearing. Adult listeners with normal hearing judged the intelligibility of the words in the BIT sentences, identified the PUP sentences as one of four grammatical or emotional moods (i.e., declarative, interrogative, happy, or sad), and rated the PUP sentences according to how well they thought the child conveyed the designated mood. Results—Percent correct scores were higher for intelligibility than for prosody and higher for children with normal hearing than for children with cochlear implants. Declarative sentences were most readily identified and received the highest ratings by adult listeners; interrogative sentences were least readily identified and received the lowest ratings. Correlations between intelligibility and all mood identification and rating scores except declarative were not significant. Discussion—The findings suggest that the development of speech intelligibility progresses ahead of prosody in both children with cochlear implants and children with normal hearing; however, children with normal hearing still perform better than children with cochlear implants on measures of intelligibility and prosody even after accounting for hearing age. Problems with interrogative intonation may be related to more general restrictions on rising intonation, and th

Introduction: Analytic, Continental and the question of a bridge

This is the peer reviewed version of the following article: Introduction: Analytic, Continental and the question of a bridge, which has been published in final form at 10.1177/1474885115582078. This article may be used for non-commercial purposes in accordance with SAGE’s Terms and Conditions for Self-Archiving.In philosophy and political theory, divisions come and go, but some persist despite beingobviously problematic. The analytic and Continental divide is one such division. Inpolitical philosophy and political theory, the division has been particularly pronounced.Analytic and Continental thinkers are divided not only over substantial issues but also over the very nature of political theorising. In spite of this fundamental nature, theorists often seem to assume that, as a division, the analytic/Continental divide requires no explanation. We suggest that, as a central division within political theory, and despite being acknowledged as problematic for quite some time, it has persisted because it has not been adequately examined. Once examined, the division turns out to be operationally weaker than it once was. In recent years, there has been a growing interest in engaging thinkers from the other side. This has been accompanied by a corresponding tendency, among both analytic and Continental philosophers and political thinkers, to reflect on the nature of their own tradition and ‘philosophy’. Both traditions have entered a self-conscious period of meta-reflection. Such questioning indicates the possibility of transformation within both groups, in the absence of settled frameworks and divisions. However, it is also clear that such signs are the beginning of the possibility of a new relation rather than a sign of the eclipse of the division. The continued institutional separation and the space between their respective philosophical vocabularies suggest that, while the time is ripe for work here, there is still much to be done

Exact phase diagrams for an Ising model on a two-layer Bethe lattice

Using an iteration technique, we obtain exact expressions for the free energy and the magnetization of an Ising model on a two - layer Bethe lattice with intralayer coupling constants J1 and J2 for the first and the second layer, respectively, and interlayer coupling constant J3 between the two layers; the Ising spins also couple with external magnetic fields, which are different in the two layers. We obtain exact phase diagrams for the system.Comment: 24 pages, 2 figures. To be published in Phys. Rev. E 59, Issue 6, 199

Coherence and Decoherence in Biological Systems: Principles of Noise Assisted Transport and the Origin of Long-lived Coherences

The quantum dynamics of transport networks in the presence of noisy environments have recently received renewed attention with the discovery of long-lived coherences in different photosynthetic complexes. This experimental evidence has raised two fundamental questions: Firstly, what are the mechanisms supporting long-lived coherences and secondly, how can we assess the possible functional role that the interplay of noise and quantum coherence might play in the seemingly optimal operation of biological systems under natural conditions? Here we review recent results, illuminate them at the hand of two paradigmatic systems, the Fenna-Matthew-Olson (FMO) complex and the light harvesting complex LHII, and present new progress on both questions. In particular we introduce the concept of the phonon antennae and discuss the possible microscopic origin or long-lived electronic coherences.Comment: Paper delivered at the Royal Society Discussion Meeting "Quantum-coherent energy transfer: implications for biology and new energy technologies", 27 - 28 April 2011 at The Kavli Royal Society International Centre, Buckinghamshire, UK. Accepted for publication in Philosophical Transactions of the Royal Society