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I. L. Davies K. E. Markides M. L. Lee M. W. Raynor K. D. Bartle 《Journal of separation science》1989,12(4):193-207
Although coupled liquid chromatographygas chromatography (LC-GC) was first demonstrated ten years ago, only in the last few years has there been a sudden surge of interest in the technique. Approximately 70% of the total number of LC-GC applications have been published in the last two years (1987–88) alone. This review categorizes LC-GC publications into four main application areas: fossil fuels, foods, environmental samples, biologiical/pharmaceutical samples, and miscellaneous samples. Multidimensional separations carried out using other coupled-column chromatographic techniques (such as supercritical fluid chromatography (SFC) with GC, and on-line trace enrichment-GC) have also been included in this review. 相似文献
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M. N. Davies 《The Journal of the Operational Research Society》1994,45(12):1363-1373
For the last ten years or so, developments in simulation software and methodology have been focused in two areas: (1) automating the model-building process; and (2) interfacing with other techniques and systems. That both academic and commercial research continues to be carried out in these areas is evidence of the continued popularity of the simulation technique. The most popular application areas where simulation modelling is used include manufacturing (engineering and process), warehousing and communications; not surprisingly, research and developments have therefore been concentrated in these areas. This paper describes the development of a simulation model generator for a different application area, that of clerical office processing of paper and documents for financial service companies. It outlines the reasons why there is a need for such a model generator and discusses the initial design requirements. The paper goes on to detail the developments and re-defined criteria required as the model generator brief changes as a result of practical applications. 相似文献
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P. Davies 《Accreditation and quality assurance》1996,1(6):240-246
Laboratory accreditation is becoming increasingly accepted around the world as a means of identifying technically competent
laboratories. It is also being used as a mechanism for the acceptance of test data both nationally and internationally. The
concept and mechanisms of accreditation have been developed over the past 50 years. The first national laboratory accreditation
system appeared in Australia in 1947. This organisation, known as the National Association of Testing Authorities (NATA),
has since taken a leading role in developing accreditation practices that are now used world-wide in evaluating testing, measurement
and calibration laboratories. This paper examines the development of the world's first and largest laboratory accreditation
system, and looks at the difficulties and triumphs in gaining acceptance and recognition by government and industry of the
benefits of laboratory accreditation.
Received: 24 June 1996 Accepted: 25 June 1996 相似文献
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We derive and analyse four algorithms for computing the current induced on a thin straight wire by a transient electric field.
They all involve solving the thin wire electric field integral equations (EFIEs) and consist of a very accurate differential
equations solver together with various schemes to approximate the vector potential integral equation. We carry out a rigorous
numerical stability analysis of each of these methods. This has not previously been done for solution schemes for the thin
wire EFIEs. Each scheme is shown to be stable and convergent provided the radius of the wire is small enough for the thin
wire equations to be a valid model. 相似文献
10.
P. J. Skevington M. A. G. Halliwell M. H. Lyons S. J. Amin M. A. Z. Rejman-Greene G. J. Davies 《Journal of Crystal Growth》1992,120(1-4):328-332
InP/InGaAs multiple quantum well structures with up to 200 periods have been grown by CBE. These structures exhibit exceptional lateral uniformity, measured as ±1 Å in period, ±13 ppm in lattice mismatch and ±0.5 nm in wavelength across a 2 inch wafer. Good surface morphology, sharp interfaces and excellent growth control have all been demonstrated. 相似文献