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This paper reports on a survey of UK members of the Institute of Physics selected on the basis of an expected research association to the Engineering and Physical Sciences Research Council (EPSRC) during the years 1995 and 1996. The survey assesses the EPSRC's ‘college’ system for research evaluation from the perspective of members of the EPSRC's colleges and from those researchers who have only seen the system from the outside. Insights into the workings of a college-based peer-review system are gained, particularly in regard to referee expertise and the most effective provision of information to prioritisation committees who must award or decline applications formally based on referee opinion of an applicant's submission. Copyright , Beech Tree Publishing.

A neutron small-angle scattering study of the flux-line lattice in heavily twinned YBa2Cu3O72x is presented. It is found that the diffraction signal disappears at temperatures well below Tc , associated with a melting of the flux lattice. The shape of the melting line is consistent with both a Lindemann criterion and the scaling expected for a vortex-glass transition with the superconducting parameters from the three-dimensional XY model. The influence of twin planes on the structure of the vortex lattice and its melting is studied by applying the field at different angles to the c axis. The results are compared with recent specific heat measurements on similar crystals. @S0163-1829~98!03022-7#

We present a high-resolution synchrotron X-ray diffraction study of xenon adsorbed on single-crystal graphite for coverages of two, three and six monolayers. We observe the evolution of the lattice mismatch between the xenon overlayer and a square root 3* square root 3R30 degrees structure commensurate with the underlying substrate. In the case of the bilayer we see a first-order incommensurate-commensurate (IC-C) phase transition at 62.0 K+or-1.2 K, which we demonstrate is consistent with the layer closest to the substrate having locked into the commensurate sites. The role of substrate quality is discussed and we conclude that previous studies on relatively poorer substrates may have favoured equilibrium structures strongly influenced by the surface imperfections. The risk of an insufficiently equilibrated adsorbate is discussed in the context of the very slow kinetics we observe for multilayer xenon on high-quality substrates. For the three- and six-layer adsorbates we observe a systematic increase in lattice mismatch with film thickness and no indication of an incommensurate-commensurate transition. We conclude that the trilayer system consists of many distinct domains approximately 500 AA across, each of which has a random close packed structure.

In common with some other recent critical scattering studies we have observed the presence of a second component in the critical fluctuations close to the continuous magnetic phase transition in USb. It is found that the magnetic anisotropy of this second component does not exhibit the same directional dependence as the {open_quote}{open_quote}normal{close_quote}{close_quote} critical scattering and that the critical behavior of this feature is not consistent with an Ornstein-Zernike treatment of the scaling. {copyright} {ital 1996 The American Physical Society.}