University of Bath

About: University of Bath is a education organization based out in Bath, Bath and North East Somerset, United Kingdom. It is known for research contribution in the topics: Population & Context (language use). The organization has 15830 authors who have published 39608 publications receiving 1358769 citations. The organization is also known as: Bath University.

Morphological study of poly(vinylidene fluoride) asymmetric membranes: Effects of the solvent, additive, and dope temperature

Abstract: Asymmetric poly(vinylidene fluoride) (PVDF) membranes were cast with commercial-grade Kynar K760 polymer pellets and four different solvent systems: N,N-dimethylacetamide (DMAc), N,N-dimethylformamide, 1-methyl-2-pyrrolidone, and triethyl phosphate. With a focus on the PVDF/DMAc system, the effects of various additives (i.e., ethanol, glycerol, lithium chloride, lithium perchlorate, and water) on the resulting membrane morphology were investigated. The membrane morphology was examined with scanning electron microscopy. The effect of the dope solution temperature on the membrane morphology was also studied for the various additives used. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1782–1789, 2004

Light trapping in gravity-like potentials and expansion of supercontinuum spectra in photonic-crystal fibres

Abstract: Femtosecond pulses of light propagating along photonic-crystal fibres can generate a broad optical supercontinuum1,2. This striking discovery has applications ranging from spectroscopy and metrology3 to telecommunication4 and medicine5,6. Among the physical principles underlying supercontinuum generation are soliton emission7, a variety of four-wave mixing processes8,9,10,11, Raman-induced soliton self-frequency shift12,13, and dispersive wave generation mediated by solitons7,13,14. Although all of the above effects contribute to supercontinuum generation, none of them can explain the generation of blue and violet light from infrared femtosecond pump pulses. In this work we argue that the most profound role in the shaping of the short-wavelength edge of the continuum is played by the effect of radiation trapping in a gravity-like potential created by accelerating solitons. The underlying physics of this effect has a straightforward analogy with the inertial forces acting on an observer moving with a constant acceleration.

Jute-reinforced polyester composites

Abstract: Raw jute fibre has been incorporated in a polyester resin matrix to form uniaxially reinforced composites containing up to 60 vol% fibre. The tensile strength and Young's modulus, work of fracture determined by Charpy impact and inter-laminar shear strength have been measured as a function of fibre volume fraction. These properties all follow a Rule of Mixtures relationship with the volume fraction of jute. Derived fibre strength and Young's modulus were calculated as 442 MN m−2 and 55.5 GN m−2 respectively. Polyester resin forms an intimate bond with jute fibres up to a volume fraction of 0.6, above which the quantity of resin is insufficient to wet fibres completely. At this volume fraction the Young's modulus of the composite is approximately 35 GN m−2, the tensile strength is 250 MN m−2, the work of fracture is 22 kJ m−2 and the inter-laminar shear strength is 24 MN m−2. The properties of jute and glass fibres are compared, and on a weight and cost basis jute fibres are seen in many respects to be superior to glass fibres as a composite reinforcement.

Security of Energy Supply: Comparing Scenarios from a European Perspective

Abstract: This paper compares different results from a set of energy scenarios produced by international energy experts, in order to analyze projections on increasing European external energy dependence and vulnerability. Comparison among different scenarios constitutes the basis of a critical review of existing energy security policies, suggesting alternative or complementary future actions. According to the analysis, the main risks and negative impacts in the long term could be the increasing risk of collusion among exporters due to growing dependence of industrialized countries and insufficient diversification; and a risk of demand/supply imbalance, with consequent instability for exporting regions due to insufficient demand, and lack of infrastructures due to insufficient supply. Cooperation with exporting countries enhancing investments in production capacity, and with developing countries in order to reinforce negotiation capacity of energy importing countries seem to be the most effective policies at international level.