Chemical Sensing Using a Polymer Coated Long-Period Fiber Grating Interrogated by Ring-Down Spectroscopy

An etched long-period grating was used as a refractive index sensor for vapours of four volatile organic compounds, i.e. m-xylene, cyclohexane, trichloroethylene and commercial gasoline. The sensitivity to the vapours was further increased by solid-phase microextraction into a coating made of polydimethylsiloxane (PDMS)/polymethyl-octylsiloxane (PMOS) co-polymer. By further amplification of the optical loss in an optical cavity made of two identical fiber-Bragg gratings and interrogation by phase-shift cavity ring-down spectroscopy we could detect and distinguish xylene (detection limit: 134ppm) from trichloroethylene (3300ppm), cyclohexane (1850ppm) and gasoline (10,500ppm).

Optical Fiber Sensing Based on Reflection Laser Spectroscopy

An overview on high-resolution and fast interrogation of optical-fiber sensors relying on laser reflection spectroscopy is given. Fiber Bragg-gratings (FBGs) and FBG resonators built in fibers of different types are used for strain, temperature and acceleration measurements using heterodyne-detection and optical frequency-locking techniques. Silica fiber-ring cavities are used for chemical sensing based on evanescent-wave spectroscopy. Various arrangements for signal recovery and noise reduction, as an extension of most typical spectroscopic techniques, are illustrated and results on detection performances are presented.

TENDENCIA THATCHERITIS OR ENGLISHNESS REMADE: The Fictions of Julian Barnes, Hanif Kureishi and Pat Barker

Julian Barnes, Pat Barker, and Hanif Kureishi are all canonical authors whose fictions are widely believed to reflect the cultural and political state of a nation that is post-war, post-imperial and post-modern. While much has been written on how Barker’s and Kureishi’s early works in particular respond to and intervene in the presiding political narrative of the 1980s – Thatcherism – treatment of how revenants of Thatcherism have shaped these writers’ works from 1990 on has remained cursory. Thatcherism is more than an obvious historical reference point for Barker, Barnes, and Kureishi; their works demonstrate a sophisticated understanding of how Thatcher’s reworkings of the repertoires of Englishness – a representational as well as political and cultural endeavour – persist beyond her time in office. Barnes, Barker, and Kureishi seem to have reached the same conclusion as political and cultural critics: Thatcher and Thatcherism have remade not only the contemporary political and cultural landscapes but also the electorate and consequently the English themselves. Tony Blair’s conception of the New Britain proved less than satisfactory because contemporary repertoires of Englishness repeat and rework historical and not incidentally imperial formulations of England and Englishness rather than envision civic and populist formulations of renewal. Barnes’s England, England and Arthur & George confront the discourse of inevitability that has come to be attached to contemporary formulations of both political and cultural Englishness – both in terms of its predictable demise and its belated celebration. Kureishi’s The Buddha of Suburbia and “The Body” speak to an alteration that has taken place in which historical Englishness and Thatcherism have become complementary rather than contrasting discourses. What Barker’s Border Crossing and Double Vision offer against this backdrop is a subtle interrogation of how renewal itself comes to be a presiding mode of cultural reflection that absorbs revolutionary possibility.