8,117 research outputs found
Explaining the fuel protests
We describe and analyse the fuel protests in the UK in September and November 2000. We draw on theories of social movements to explain the success of the first of these protests and the failure of the second. We show how the loose, network forms of organisation contributed to the success in September, and the attempts to impose more formal organisations helped to cause the failure in November. We also show how the success of the protests depended on the articulation of the aims of the protestors with dominant social forces in British politics, in particular the oil companies, the police, and the mass media
Complex permeability of soft magnetic ferrite polyester resin composites at frequencies above 1 MHz
Composite soft magnetic materials consist of magnetic particles in a non-magnetic matrix. The properties of such materials can be modelled using effective medium theory. Measurements have been made of the complex permeability of composites produced using ferrite powder and polyester resin. The success of various effective medium expressions in predicting the variation of complex permeability with composition has been assessed
Workshop on the Polar Regions of Mars: Geology, Glaciology, and Climate History, part 1
Papers and abstract of papers presented at the workshop are presented. Some representative titles are as follows: Glaciation in Elysium; Orbital, rotational, and climatic interactions; Water on Mars; Rheology of water-silicate mixtures at low temperatures; Evolution of the Martian atmosphere (the role of polar caps); Is CO2 ice permanent; Dust transport into Martian polar latitudes; Mars observer radio science (MORS) observations in polar regions; and Wind transport near the poles of Mars (timescales of changes in deposition and erosion)
The Phase Diagram of the Sigma Model
We study the phase diagram of the scalar model in
dimensions. We find that the phase transition is of first order in most of the
parameter space. The theory can still be relevant to continuum physics (as an
effective theory) provided the transition is sufficiently weakly first order.
This places restrictions on the allowed coupling constants.Comment: 3 pages (Latex), 2 eps figures, uses espcrc2.sty, epsf, talk given at
LATTICE9
Electrically tunable selective reflection of light from ultraviolet to visible and infrared by heliconical cholesterics
Cholesteric liquid crystals with helicoidal molecular architecture are known
for their ability to selectively reflect light with the wavelength that is
determined by the periodicity of molecular orientations. Here we demonstrate
that by using a cholesteric with oblique helicoidal(heliconical) structure, as
opposed to the classic right-angle helicoid, one can vary the wavelength of
selectively reflected light in a broad spectral range, from ultraviolet to
visible and infrared (360-1520 nm for the same chemical composition) by simply
adjusting the electric field applied parallel to the helicoidal axis. The
effect exists in a wide temperature range (including the room temperatures) and
thus can enable many applications that require dynamically controlled
transmission and reflection of electromagnetic waves, from energy-saving smart
windows to tunable organic lasers, reflective color display, and transparent
see-through displays.Comment: 11 pages, 5figure
Suprathermal plasma observed on STS-3 Mission by plasma diagnostics package
Artificially produced electron beams were used extensively during the past decade as a means of probing the magnetosphere, and more recently as a means of actively controlling spacecraft potential. Experimentation in these areas has proven valuable, yet at times confusing, due to the interaction of the electron beam with the ambient plasma. The OSS-1/STS-3 Mission in March 1982 provided a unique opportunity to study beam-plasma interactions at an altitude of 240 km. On board for this mission was a Fast Pulse Electron Generator (FPEG). Measurements made by the Plasma Diagnostics Package (PDP) while extended on the Orbiter RMS show modifications of the ion and electron energy distributions during electron beam injection. Observations made by charged particle detectors are discussed and related to measurements of Orbiter potential. Several of the PDP instruments, the joint PDP/FPEG experiment, and observations made during electron beam injection are described
Infinite dimensional integrals beyond Monte Carlo methods: yet another approach to normalized infinite dimensional integrals
An approach to (normalized) infinite dimensional integrals, including
normalized oscillatory integrals, through a sequence of evaluations in the
spirit of the Monte Carlo method for probability measures is proposed. in this
approach the normalization through the partition function is included in the
definition. For suitable sequences of evaluations, the ("classical")
expectation values of cylinder functions are recoveredComment: Submitted as a communication in the ICMSQUARE conference, september
201
Molecular Flexibility and Bend in SemiāRigid Liquid Crystals: Implications for the Heliconical Nematic Ground State
The NTB phase phases possess a local helical structure with a pitch length of a few nanometers and is typically exhibited by materials consisting of two rigid mesogenic units linked by a flexibile oligomethylene spacer of odd parity, giving a bent shape. We report the synthesis and characterisation of two novel dimeric liquid crystals, and perform a computational study on ten cyanobiphenyl dimers with varying linking groups, generating a large library of conformers for each compound; this allows us to present molecular bend angles as probability weighted averages of many conformers, rather than use a single conformer. We validate conformer libraries by comparison of interproton distances with those obtained from solution based 1D 1H NOESY NMR, finding good agreement between experiment and computational work. Conversely, we find that using any single conformer fails to reproduce experimental interproton distances. We find the use of a single conformer significantly overestimates the molecular bend angle while also ignoring flexibility; we show that the average bend angle and flexibility are both linked to the relative stability of the NTB phase
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