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Current and future water demand pressures arising from inadequate supplies and forecasts of increased population in the UK have prompted the government and other stakeholders to set up strategies that will ensure sustainable water supplies. Demand-side management strategies are one of the key priorities being pursued and the water regulator, Ofwat, has set a target of 13% reduction from 2010 levels of per capita household water consumption in England and Wales by 2030. This paper reports on estimated water wastage in UK households resulting from users waiting for water to reach a sufficiently warm temperature when using a hot water outlet (including kitchen sinks, showers and hand wash basins). It is estimated that, on average, 10% of the daily average per capita water consumption in UK households is wasted in this way. Possible means of reducing this waste are identified and a recommendation is made that boilers should carry a water efficiency rating in addition to the standard energy efficiency rating.

An outline is given of a method for high resolution BSE analysis of chemical composition across interfaces in bulk semiconductor specimens. In this method the effects of electron beam diameter and beam spreading, which normally limit spatial resolution, are largely removed by a deconvolution technique in which these effects are measured experimentally. Line profiles giving 10-90% interface widths as low as 19nm have been obtained at 30kV from an abrupt interface.

InAs/GaSb strained layer superlattices (SLSs) have been grown by metalorganic vapour phase epitaxy (MOVPE) at atmospheric pressure. Initially the interfaces of the SLS have been biased towards pairs of GaAs or InSb using three different gas switching sequences. Room temperature Raman optical modes show that growing the interfaces using an ALE (atomic layer epitaxy) like switching sequence gives interfaces of very high quality probably near the optimum, which is a monolayer. Growing with other switching sequences leads to one of the interfaces being non-uniform. By growing samples with alternating (InSb,GaAs or GaAs,InSb) pairs of interfaces it is possible to unambiguously assign this non-uniformity to one of the two possible interfaces for the first time. Furthermore, the influence of the band overlap on interface type has been studied using optimised SLSs in the semimetallic regime.

The EBIC contrast from extended defects in semiconductors can, in principle, be related to the defect capture cross-section for minority carriers and hence to the details of the recombination behaviour of individual defects. The monitoring of EBIC contrast as a function of temperature and dopant concentration is proposed as a possible method for deducing the positions of energy levels associated with well-characterised, individual dislocations. Some results of such an investigation are presented to show that current theoretical interpretations of the EBIC contrast are unable to describe correctly the observed temperature-dependent properties of the contrast. Possible modifications, which may enable theoretical treatments to describe better the experimental results, are suggested.