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Rurality, productivity and skills in the East Midlands: final report
This report sets out the findings of research into the relationship between rurality, skills and productivity in the East Midlands. The report has been prepared by the Enterprise Research and Development Unit (ERDU) at the University of Lincoln on behalf of the East Midlands Development Agency (emda)
The earth’s core: an approach from first principles
The Earth’s core is largely composed of iron (Fe), alloyed with less dense elements such as
sulphur, silicon and/or oxygen. The phase relations and physical properties of both solid and
liquid Fe-alloys are therefore of great geophysical importance. As a result, over the past fifty
years the properties of Fe and its alloys have been extensively studied experimentally.
However, achieving the extreme pressures (up to 360 GPa) and temperatures (~6000K) found
in the core provide a major experimental challenge, and it is not surprising that there are still
considerable discrepancies in the results obtained by using different experimental techniques.
In the past fifteen years quantum mechanical techniques have been applied to predict the
properties of Fe. Here we review the progress that has been made in the use of first principles
methods to study Fe and its alloys, and as a result of these studies we conclude: (i) that pure
Fe adopts an hexagonal close packed structure under core conditions and melts at ~6200 K at
360 GPa, (ii) that thermodynamic equilibrium and observed seismic data are satisfied by a
liquid Fe alloy outer core with a composition of ~10 mole% S (or Si) and 8 mole% O
crystallising at ~ 5500 K to give an Fe alloy inner core with ~8 mole% S (or Si) and 0.2 mole
% O, and (iii) that with such concentrations of S (or Si), an Fe alloy might adopt a body
centred cubic structure in all or part of the inner core. In the future the roles of Ni, C, H and
K in the core need to be studied, and techniques to predict the transport and rheological
properties of Fe alloys need to be developed
Marine tethysuchian crocodyliform from the ?Aptian-Albian (Lower Cretaceous) of the Isle of Wight, UK
A marine tethysuchian crocodyliform from the Isle of Wight, most likely from the Upper Greensand Formation (upper Albian, Lower Cretaceous), is described. However, we cannot preclude it being from the Ferruginous Sands Formation (upper Aptian), or more remotely, the Sandrock Formation (upper Aptian-upper Albian). The specimen consists of the anterior region of the right dentary, from the tip of the dentary to the incomplete fourth alveolus. This specimen increases the known geological range of marine tethysuchians back into the late Lower Cretaceous. Although we refer it to Tethysuchia incertae sedis, there are seven anterior dentary characteristics that suggest a possible relationship with the Maastrichtian-Eocene clade Dyrosauridae. We also review ‘middle’ Cretaceous marine tethysuchians, including putative Cenomanian dyrosaurids. We conclude that there is insufficient evidence to be certain that any known Cenomanian specimen can be safely referred to Dyrosauridae, as there are some cranial similarities between basal dyrosaurids and Cenomanian–Turonian marine ‘pholidosaurids’. Future study of middle Cretaceous tethysuchians could help unlock the origins of Dyrosauridae and improve our understanding of tethysuchian macroevolutionary trends
The cost of systemic corticosteroid-induced morbidity in severe asthma : a health economic analysis
The study data-set was supported by the Respiratory Effectiveness Group through their academic partnership with Optimum Patient Care. Ciaran O'Neill was funded under a HRB Research Leader Award (RL/13/16).Peer reviewedPublisher PD
Piezoelectric copolymer hydrophones for ultrasonic field characterization
Hydrophones to be used in the characterization of medical ultrasonic transducers have
been fabricated using a new polyvinylidene fluoride/trifluoroethylene (VF2/VF3)
copolymer. The copolymer has an advantage over VF2 in that it does not require
prestretching before poling. Thin copolymer films can be cast from solution and then
poled using the corona discharge method. As there is a need for small‐diameter
hydrophones to provide good spatial resolution in measuring highly focused ultrasonic
beams, hydrophones with diameter as small as 0.1 mm have been made. Both
needle‐type and line hydrophones have been tested and their performance reported. In
the case of line hydrophones, the output signal is proportional to the line integral of the
acoustic pressure and a computer tomographic technique has been used to reconstruct the
beam profiles
A New Concept for Controlled Lifting Entry Flight Experiments
Feasibility of trajectory guidance and control concept for lifting configuration with roll modulatio
Flow properties of a series of experimental thermoplastic polymides
The softening temperature to degradation temperature range of the polymers was about 440 to 650 K. All of the polymers retained small amounts of solvent as indicated by an increase in T(sub g) as the polymers were dried. The flow properties showed that all three polymers had very high apparent viscosities and would require high pressures and/or high temperatures and/or long times to obtain adequate flow in prepregging and molding. Although none was intended for such application, two of the polymers were combined with carbon fibers by solution prepregging. The prepregs were molded into laminates at temperatures and times, the selection of which was guided by the results from the flow measurements. These laminates had room temperature short beam shear strength similar to that of carbon fiber laminates with a thermosetting polyimide matrix. However, the strength had considerable scatter, and given the difficult processing, these polymides probably would not be suitable for continuous fiber composites
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