Silicon material task. Part 3: Low-cost silicon solar array project

The feasibility of a process for carbon reduction of low impurity silica in a plasma heat source was investigated to produce low-cost solar-grade silicon. Theoretical aspects of the reaction chemistry were studied with the aid of a computer program using iterative free energy minimization. These calculations indicate a threshold temperature exists at 2400 K below which no silicon is formed. The computer simulation technique of molecular dynamics was used to study the quenching of product species

Evaluating teachers' and trainers' development in a large scale curriculum development project in South Yorkshire

The evaluative research upon which the paper is based focuses on the first three years of a six-year project “Pathways to Success” (PW) currently taking place in South Yorkshire and funded by the European Social Fund (ESF) as part of the Objective 1 programme from 2001-2007. Matched funding has been provided by schools, colleges and LEAs. The PW project is concerned with developing innovative curricula to raise achievement and improve youngsters' employability skills. The project is set in the context of regional regeneration in an area where unemployment is higher than the European (and national) average, due to the decline of traditional steel and coal industries and where the gross domestic product is less than 75% of the European average. South Yorkshire is also an area where overall achievement in schools at all stages is lower than the national average and participation in post-16 education and higher education is persistently below national figures. Although employment is slowly rising due to reorientation from manufacturing towards a service and knowledge-based economy, pockets of severe unemployment and deprivation remain and are among the ten worst in the country.</p

New Pathways: evaluating the implementation of a major work- related programme in Northern England

The evaluative research upon which this paper is based is focussed on the implementation of a three-year programme “Pathways to Success” (usually shortened to “Pathways”) in South Yorkshire, England. It is part of a much larger regional regeneration project funded by the European Social Fund (ESF) from 2001-2004. The Pathways programme is concerned with developing innovative curricula for the 14-19 age range in four Local Education Authorities (LEAs)1 and is taking place in 76 secondary (high) schools. A team from Sheffield Hallam University was responsible for evaluating the success of the Pathways programme and our findings reported here refer to the first year of implementation.</p

Optimisation of quantum Monte Carlo wave function: steepest descent method

We have employed the steepest descent method to optimise the variational ground state quantum Monte Carlo wave function for He, Li, Be, B and C atoms. We have used both the direct energy minimisation and the variance minimisation approaches. Our calculations show that in spite of receiving insufficient attention, the steepest descent method can successfully minimise the wave function. All the derivatives of the trial wave function respect to spatial coordinates and variational parameters have been computed analytically. Our ground state energies are in a very good agreement with those obtained with diffusion quantum Monte Carlo method (DMC) and the exact results.Comment: 13 pages, 3 eps figure

Pathways to "opportunity and excellence": collaborative curriculum innovation in South Yorkshire

This paper reports on two aspects of a large-scale curriculum project currently taking place in four LEAs in South Yorkshire. The first of these is concerned with the positive and negative influences on effective curriculum innovation and is addressed from the perspective of the LEA project managers who are managing the delivery of the project in the region's schools. The second aspect considers what the pupils (Year 10, age 14-15) think about the new learning opportunities. The project is set in the context of regional regeneration. The paper concludes that the extremely positive responses from the sample of pupils in all three strands of the programme indicate that the greater emphasis on vocational work and work experience in schools is having a strong motivational effect on pupils who are responding with improved attendance, behaviour and achievement.</p

Developing enterprise culture in a northern educational authority in the UK: involving trainee teachers in learning-orientated evaluation

In this paper we discuss our use of innovative methods - at least in the context of regeneration evaluation - to help evaluate an enterprise project in northern England, paying particular attention to the involvement of trainee teachers. We discuss the methods used and critically appraise the methods and methodology, present some emerging findings from the trainee teachers strand and conclude by discussing the place of what might be termed 'learning-orientated evaluation' in relation to the currently dominant output-focussed evaluation paradigm.</p

Performance of nano-structured multilayer PVD coating TiAlN/VN in dry high speed milling of aerospace aluminium 7010-T7651

A low-friction and wear resistant TiAlN/VN multilayer coating with TiAlN/VN bilayer thickness 3 nm has been grown by using the combined cathodic arc etching and unbalanced magnetron sputtering deposition on high speed steel tools for dry cutting of aluminium alloys. In this paper, in-lab and industrial high speed milling tests have been performed on an aerospace aluminium alloy 7010-T7651. The results show that the TiAlN/VN coated tools achieved lower cutting forces, lower metal surface roughness, and significantly longer tool lifetime by three times over the uncoated tools as a result of the low friction and eliminated tool-metal adhesion. Under the same conditions, a TiAlN based multicomponent coating TiAlCrYN also increased the tool lifetime by up to 100% despite the high cutting forces measured

Triplets of Quasars at high redshift I: Photometric data

We have conducted an optical and infrared imaging in the neighbourhoods of 4 triplets of quasars. R, z', J and Ks images were obtained with MOSAIC II and ISPI at Cerro Tololo Interamerican Observatory. Accurate relative photometry and astrometry were obtained from these images for subsequent use in deriving photometric redshifts. We analyzed the homogeneity and depth of the photometric catalog by comparing with results coming from the literature. The good agreement shows that our magnitudes are reliable to study large scale structure reaching limiting magnitudes of R = 24.5, z' = 22.5, J = 20.5 and Ks = 19.0. With this catalog we can study the neighbourhoods of the triplets of quasars searching for galaxy overdensities such as groups and galaxy clusters.Comment: The paper contains 12 figures and 3 table

SMART precision interferometry at 794 nm

Single-mode fibers have been used in the near-infrared to dramatically reduce calibration error for long-baseline interferometry. We have begun an effort to apply the advantages of spatial filtering at visible wavelengths for precision measurements of pulsating Cepheids using the IOTA interferometer. Rather than employing photometric taps to calibrate fluctuating coupling efficiency, we are using an "asymmetric" coupler which allows this calibration to be done without losing photons. The Single-Mode Asymmetric Recombination Technique (SMART) experiment has finished lab-testing, and has been installed at IOTA for full commissioning in Summer 2002. We report the results of lab characterization and first sky tests, as well as first fringes on a star using a visible-wavelength single-mode coupler. With both lab and sky experience using unpolarized light, we have found that circular silica fibers are quite practical for precision interferometric measurements. We conclude that circular fibers (as opposed to polarization maintaining fibers) have an undeserved poor reputation and that birefringence effects pose no significant difficulty