Effects of decontamination, sterilization, and thermal vacuum on polymeric products

Adhesives, coatings, coated fabrics, elastomers, encapsulants, films, hardware and structural materials, and tapes are tested in a series of physical, mechanical, and electrical tests. Material properties are measured before and after exposure to the three environments

Benchmarking Regional Innovation: A Comparison of Bavaria, Northern Ireland and the Republic of Ireland

Regional regeneration strategies based on developing innovation capability have received much support in recent years. Evaluation of the effectiveness of such initiatives has, however, been limited largely to an assessment of the impact of such strategies on policy frameworks and attitudes. Based on innovation survey data covering nearly a decade, this paper outlines a number of external innovation benchmarks for core and peripheral regions within the EU. The benchmarks considered cover the innovation objectives, constraints resources, linkages and outputs of manufacturing firms. Despite considerable efforts in recent years to develop the innovation capability and institutional support framework for innovation in Northern Ireland and the Republic of Ireland, the benchmarks still point to a substantial performance gap between the Irish and German study regions and provide little evidence of convergence over the 1991-99 period. The benchmarks also suggest other more general points emphasising, for example, a general shortening of product lifecycles and a related shift towards more radical innovation. More disappointing is in that in each of the study regions the development of environmentally friendly products is given a low and diminishing priority by manufacturing firms.

Job Creation and Destruction in Northern Ireland - 1973-1993

Job creation and destruction estimates are made for Northern Ireland manufacturing using the ARD database. International comparisons suggest job creation and destruction rates in Northern Ireland were below those elsewhere. Job turnover rates exhibit the standard properties, however, with counter-cyclical job destruction and pro-cyclical job creation. A number of other key results emerge. First, small firms are the only size band for which the net change in employment was positive. Second, job turnover in small firms is less cyclical than that in larger companies. Third, firm contraction and expansion were more important sources of job creation and destruction in Northern Ireland than in the UK as a whole.

The thinning of lamellae in surfactant-free foams with non-Newtonian liquid phase

Thinning rates of liquid lamellae in surfactant-free non-Newtonian gas–liquid foams, appropriate for ceramic or polymer melts and also in metals near the melting point, are derived in two dimensions by matched asymptotic analysis valid at small capillary number. The liquid viscosity is modelled (i) as a power-law function of the shear rate and (ii) by the Ellis law. Equations governing gas–liquid interface dynamics and variations in liquid viscosity are derived within the lamellar, transition and plateau border regions of a corner of the liquid surrounding a gas bubble. The results show that the viscosity varies primarily in the very short transition region lying between the lamellar and the Plateau border regions where the shear rates can become very large. In contrast to a foam with Newtonian liquid, the matching condition which determines the rate of lamellar thinning is non-local. In all cases considered, calculated lamellar thinning rates exhibit an initial transient thinning regime, followed by a t−2 power-law thinning regime, similar to the behaviour seen in foams with Newtonian liquid phase. In semi-arid foam, in which the liquid fraction is O(1) in the small capillary number, results explicitly show that for both the power-law and Ellis-law model of viscosity, the thinning of lamella in non-Newtonian and Newtonian foams is governed by the same equation, from which scaling laws can be deduced. This result is consistent with recently published experimental results on forced foam drainage. However, in an arid foam, which has much smaller volume fraction of liquid resulting in an increase in the Plateau border radius of curvature as lamellar thinning progresses, the scaling law depends on the material and the thinning rate is not independent of the liquid viscosity model parameters. Calculations of thinning rates, viscosities, pressures, interface shapes and shear rates in the transition region are presented using data for real liquids from the literature. Although for shear-thinning fluids the power-law viscosity becomes infinite at the boundaries of the internal transition region where the shear rate is zero, the interface shape, the pressure and the internal shear rates calculated by both rheological models are indistinguishable

Pairwise interactions in inertially-driven one-dimensional microfluidic crystals

In microfluidic devices, inertia drives particles to focus on a finite number of inertial focusing streamlines. Particles on the same streamline interact to form one-dimensional microfluidic crystals (or "particle trains"). Here we develop an asymptotic theory to describe the pairwise interactions underlying the formation of a 1D crystal. Surprisingly, we show that particles assemble into stable equilibria, analogous to the motion of a damped spring. Although previously it has been assumed that particle spacings scale with particle diameters, we show that the equilibrium spacing of particles depends on the distance between the inertial focusing streamline and the nearest channel wall, and therefore can be controlled by tuning the particle radius.Comment: 15 pages, 9 figure

NOSTALGIA AS AN EMOTIONAL EXPERIENCE IN THE GREAT WAR

ABSTRACTThis article is concerned with the longing for home of British soldiers during the First World War. What, it asks, can such longings reveal about the psychological impact of trench warfare? Historians have differed in the significance that they ascribe to domestic attachments. Some argue that a ‘cultural chasm’ developed between the fronts, producing anger and disillusionment among soldiers which would surface fully fledged after the war, while others assert the continuing vitality of the links with home. Evidence for both these perceptions can be found in the letters written by British soldiers to their families. The functions of nostalgia could range from reassurance or momentary relief from boredom and impersonal army routines, through flight from intolerable anxiety, to survival through the power of love. Although animated by solitude, nostalgia provided a means of communication with loved ones. Its emotional tones varied according to the soldier's age and the nature of his attachments to home. The young soldier's reminiscences of home conveyed, not just the comforting past, but the hateful present. Nostalgia, being rooted in early memories of care, could be a potent vehicle for arousing the anxieties of loved ones, especially mothers. Among married men, the desire to return to wives and children could provide a powerful motivation for survival. This analysis suggests a different and more varied account of the genesis of the ‘disillusionment story’ of the war than is put forward in some recent studies. Among men of the ‘war generation’ particularly, disillusionment was not only a post-war construction, an artefact of cultural memory, but a powerful legacy of the emotional experience of the war itself.</jats:p

Buoyancy-driven crack propagation: the limit of large fracture toughness

We study steady vertical propagation of a crack filled with buoyant viscous fluid through an elastic solid with large effective fracture toughness. For a crack fed by a constant flux Q, a non-dimensional fracture toughness K=Kc/(3μQm3/2)1/4 describes the relative magnitudes of resistance to fracture and resistance to viscous flow, where Kc is the dimensional fracture toughness, μ the fluid viscosity and m the elastic modulus. Even in the limit K xs226B 1, the rate of propagation is determined by viscous effects. In this limit the large fracture toughness requires the fluid behind the crack tip to form a large teardrop-shaped head of length O(K2/3) and width O(K4/3), which is fed by a much narrower tail. In the head, buoyancy is balanced by a hydrostatic pressure gradient with the viscous pressure gradient negligible except at the tip; in the tail, buoyancy is balanced by viscosity with elasticity also playing a role in a region within O(K2/3) of the head. A narrow matching region of length O(K-2/5) and width O(K−4/15), termed the neck, connects the head and the tail. Scalings and asymptotic solutions for the three regions are derived and compared with full numerical solutions for K ≤ 3600 by analysing the integro-differential equation that couples lubrication flow in the crack to the elastic pressure gradient. Time-dependent numerical solutions for buoyancy-driven propagation of a constant-volume crack show a quasi-steady head and neck structure with a propagation rate that decreases like t−2/3 due to the dynamics of viscous flow in the draining tail