Abstracts for the 2015 Meeting will appear here when they become available.
Neil Eatherington, PANalytical Ltd, Environmental Science Centre.
Geochemical mapping projects require large amounts of high quality data. In this talk we will show how a combination of WD and ED(P)-XRFs can provide a good solution for the analysis of soils and sediments (and other geological material) for 50 + analytes and accredited to ISO/IEC 17025:2005.
Peter C. Webb, Philip J. Potts, Michael Thompson, The Open University.
The GeoPT proficiency testing programme provides a large body of data for geological materials derived from a variety of analytical techniques. Examination of elemental concentration distributions shows that XRF results for many trace elements (for example As, Bi, Cd, Mo, Sn, Ta and W) are frequently highly variable at concentrations approaching detection limits and often demonstrate significant positive bias. Some of the factors thought to contribute to these observations will be reviewed. We advise XRF analysts to be cautious when reporting values close to detection limits: they should give careful consideration to the extent of uncertainties, the potential for bias and whether the results satisfy their fitness for purpose criteria.
David Maclachlan, Johnson Matthey Plc
XRF analysis is often the workhorse of a QC lab that produces masses of numbers every day of the year. However it is capable of much more. XRF analysis starts from the very small scale research sample to the very large scale production sample and can be instrumental in every aspect of your product development and production process optimisation. It isn’t just a number cruncher but a process tool as well.
David Beveridge
It seems that pigment analysis is too far removed from most people's general work for this sample to have attracted many responses! So far, we've received 3. These use very different ways of tackling the problem, some more satisfactory than others. It's still not too late to send in any results that you may have!
Heather Harrison
Samples of DOT-3, a naturally occurring geological material, are being offered to delegates, free of charge, to assist in their X-ray method development. Used in the construction industry and colloquially known as ‘cement rock’, DOT-3 is gypsum based and contains minerals common to the UK. It has not been blended or spiked, it is not intended to become a reference material and does not form part of a proficiency test.
We are inviting you to determine as many major oxides and trace elements as you wish by your standard XRF applications, complementary elemental techniques (e.g. ICP) and determine phase analysis by XRD if your laboratory has the instrumentation available.
For us to compile data and provide feedback to participants, please include details of any additional sample preparation and the analytical technique(s) you adopt (e.g. fusion (including flux blend), loose powder, pressed powder pellet etc.)
Full results will be published at the next BCA meeting but details of the participating laboratories will remain confidential. We hope as many delegates as possible will take part to make the statistical evaluation meaningful and would like to thank you in advance for your contributions.
Didier Bonvin, Kurt Juchli and Raphaël Yerly , Thermo Fisher Scientific, CH 1024 Ecublens, Switzerland
Glass, Geochemical and R&D applications in metals and materials science offer interesting analytical challenges because these materials require large elemental coverage and represent wide concentration ranges and varied sample matrices and sizes. Analytical performance of wavelength dispersive X-ray fluorescence (WDXRF) instruments is being constantly advanced in order to cope with such challenges.
While traditionally WDXRF technique has always demanded homogeneous samples latest developments permit analysis of small spots down to 0.5mm as well as mapping of a selected area of a sample. These new possibilities open up the WDXRF technique to heterogeneous samples where segregations, defects or inclusions can now be determined. Coupling these capabilities with standardless analysis permits quantification of up to 79 elements of the periodic table on selected points of a specimen sample.
In this presentation, several applications will be presented in which the power and flexibility of new WDXRF instruments are fully exploited.
Rainer Schramm, FLUXANA GmbH & Co. KG, Borschelstr.3, 47551 Bedburg-Hau, Germany
In x-ray fluorescence analysis (XRF), sample preparation is an important step in the analytical procedure. A borate fusion is frequently used for the determination of main components. At the present, there are several gas and electrical fusion systems on the market. We have now developed a new automatic electrical furnace which overcomes the well-known problems and disadvantages of systems based on muffle furnaces. The design consists of a lift bottom oven where the door is the bottom and it can be opened using a lift to load the sample. The crucible containing the sample and the mold are held by a rack, which is placed onto the lift by an autosampler. The homogenization of the sample inside the furnace is solved by external spinning at the bottom with a bidirectional motor. The casting function is overtaken by the autosampler while the rack with the crucible is unloaded from the furnace.
The new system shows excellent precision and accuracy for all elements typically analyzed in oxidic materials like cements, gypsum, sands, iron ores, clays, geological samples, etc. The closed design also helps to avoid the loss of volatile elements like sulfur, fluorine and chlorine.
Frédéric DAVIDTS, SOCACHIM, Brussels / Belgium
The condition of Pt-Au crucibles and moulds is very important, to ensure reproducible sample preparation and analytical results. The difference obtained with lab ware in pristine condition, compared with deformed shape or scratched surfaces, particularly on moulds, could be very significant, and sometimes resulting figures could show variations up to a 1% difference.
Going through a series of case studies, we present techniques which will assist you in taking care of your platinum lab ware, and extend the lifetime of these expensive items.
Adrian Band, University of Leicester
Analysis of oceanic basalts has shown that the composition of the upper mantle can be divided into discrete chemical domains through changes in its Nd-Sr-Pb-Hf isotope compositions. At present these chemical domains broadly underlie the Atlantic, Pacific and Indian Ocean basins. The prolonged existence of chemical reservoirs in the mantle, despite the homogenising actions of mantle convection and plate tectonics, has major implications towards the evolution of the depleted mantle. Temporally tracing these mantle domains can be achieved through isotope analysis of ancient oceanic basalts preserved in ophiolites. Prior to isotope analysis, vigorous screening of samples is required to select lavas sourced directly from the upper mantle without chemical modification during subduction, obduction or post-tectonic weathering. XRF is a quick, reliable and cost efficient screening technique producing a range of major and trace elements useful in discriminating volcanic material. Scrutiny of preliminary XRF results allows complete classification of the geotectonic environment a lava formed within, and is a sound basis for selecting samples for further geochemical and isotopic study. Through geochemical and isotopic scrutiny of a series of 400 Ma ophiolites from Europe and Central America, we have succeeded in tracing the Indian Ocean-type mantle back into the Palaeozoic.
Led by David BeveridgeYour chance to ask a question there wasn't time for earlier in the day or come prepared to ask a specific question to help you in your day to day work. There will be a wealth of expertise in the audience just waiting to be tapped!