6,041 research outputs found
Nationhood and muslims in Britain
These are difficult times to be British,” Andrew Gamble and Tony Wright maintain. Their assessment centers on how “the state which underpinned British identity is no longer the confident structure of earlier times.” They are not alone in coming to this view, and at least two implications follow from their observation. One is that
the political unity of the administrative and bureaucratic components of the state is related to cultural features of British nationhood, including the ways in which people express feeling and being British. This is perhaps
a familiar assessment of the configuration of all nation-states, though it could also imply that the state has been one—though not necessarily the most important—touchstone in the historical cultivation of British as a
national identity
Spatial imaging of modifications to fluorescence lifetime and intensity by individual Ag nanoparticles
Highly ordered periodic arrays of silver nanoparticles have been fabricated
which exhibit surface plasmon resonances in the visible spectrum. We
demonstrate the ability of these structures to alter the fluorescence
properties of vicinal dye molecules by providing an additional radiative decay
channel. Using fluorescence lifetime imaging microscopy (FLIM), we have created
high resolution spatial maps of the molecular lifetime components; these show
an order of magnitude increase in decay rate from a localized volume around the
nanoparticles, resulting in a commensurate enhancement in the fluorescence
emission intensity.Comment: 3 pages, 2 figures, submitted Applied Physics Letter
Plasmonic engineering of metal nanoparticles for enhanced fluorescence and Raman scattering
We have investigated the effects of tuning the localized surface plasmon
resonances (LSPRs) of silver nanoparticles on the fluorescence intensity,
lifetime, and Raman signal from nearby fluorophores. The presence of a metallic
structure can alter the optical properties of a molecule by increasing the
excitation field, and by modifying radiative and non-radiative decay
mechanisms. By careful choice of experimental parameters we have been able to
decouple these effects. We observe a four-fold increase in fluorescence
enhancement and an almost 30-fold increase in decay rate from arrays of Ag
nanoparticles, when the LSPR is tuned to the emission wavelength of a locally
situated fluorophore. This is consistent with a greatly increased efficiency
for energy transfer from fluorescence to surface plasmons. Additionally,
surface enhanced Raman scattering (SERS) measurements show a maximum
enhancement occurs when both the incident laser light and the Raman signal are
near resonance with the plasmon energy. Spatial mapping of the SERS signal from
a nanoparticle array reveals highly localized differences in the excitation
field resulting from small differences in the LSPR energy.Comment: Submitted to Plasmonics (Springer
Investigation of the surface structure and activity of molybdenum oxide-containing catalysts : I. An infrared study of the surface structure of molybdena-alumina catalysts
A comparison has been made of the infrared spectra of alumina with molybdenum oxide-alumina in both the oxidized and reduced forms. In the case of molybdena-alumina prepared via adsorption of gaseous MoO2(OH)2, the spectra show that a practically complete monolayer of Mo6+ oxide covers the alumina. After reduction with hydrogen the hydroxyls of the carrier appear. From the reversibility of reduction and oxidation under mild conditions it has been established that the reduced oxide is present as an interrupted monolayer
Welfare Chauvinism in the Face of Ethnic Diversity: A Vignette Experiment across Diverse and Homogenous Neighbourhoods on the Perceived Deservingness of Native and Foreign-Born Welfare Claimants
The Inevitable Deservingness Gap: A Study into the Insurmountable Immigrant Penalty in Perceived Welfare Deservingness
Spatially encoded light for Large-alphabet Quantum Key Distribution
Most Quantum Key Distribution protocols use a two-dimensional basis such as
HV polarization as first proposed by Bennett and Brassard in 1984. These
protocols are consequently limited to a key generation density of 1 bit per
photon. We increase this key density by encoding information in the transverse
spatial displacement of the used photons. Employing this higher-dimensional
Hilbert space together with modern single-photon-detecting cameras, we
demonstrate a proof-of-principle large-alphabet Quantum Key Distribution
experiment with 1024 symbols and a shared information between sender and
receiver of 7 bit per photon.Comment: 9 pages, 6 figures, Added references, Updated Fig. 1 in the main
text, Updated Fig.1 in supplementary material, Added section Trojan-horse
attacks in supplementary material, title changed, Added paragraphs about
final key rate and overfilling the detector to result sectio
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