Articles

Yvonne Fors, Håkan Grudd, Anders Rindby and Lennart Bornmalm tell us about “X-ray fluorescence for cultural heritage: scanning biochemical fingerprints in archaeological shipwrecks”. Two outstanding examples of the preservation of wood are the warships Vasa, in Stockholm and the Mary Rose in Portsmouth and this article looks at the role XRF has played in the preservation of the wood of both ships.

Knowledge about the particles in the air is important because of their effect on our health and their impact on our climate through cloud formation and transport of nutrients into the oceans. Ursula Fittschen describes “Strategies for ambient aerosols characterisation using synchrotron X-ray fluorescence: a review”. This technique can provide elemental determination and speciation of aerosol particulates with limits of detection in the pg m–3 range for many elements.

How a cat manages to turn and land on its feet may not be the most obvious start to an article in Spectroscopy Europe. However, C.J. Milne and M. Chergui use the example in their article on “Time-resolved X-ray absorption spectroscopy” to show how the time dimension is important in many analyses and applications. There has been a real surge in time-resolved X-ray absorption studies in chemistry, biology and materials science. Picosecond time resolution is routinely achieved and femtosecond resolution has been demonstrated at synchrotrons, albeit at the cost of a significantly reduced photon flux. However, the advent of hard X-ray-free electron lasers offer the promise of making such studies routine.

Whilst fireworks are a great entertainment, they can also be used for illegal activities as well as potentially containing dangerous chemicals. The combination of Raman spectroscopy and SEM-EDS turns out to be a very efficient analytical method. In fact, these complementary techniques may also be used to analyse other kinds of pyrotechnic artefacts, low explosive formulations, high explosives, explosion residues etc.

The authors describe the use of a range of complementary methods to explore cellular, physiological and behavioural mechanisms underlying Al accumulation and toxicity, and its eventual fate, using the pond snail as a model organism.

Non-destructive, high resolution, sediment core scanners incorporating X-ray fluorescence (XRF) spectrometry are now widely used by sub-disciplines in the earth and environmental sciences and have revolutionised the analysis of sediment cores. These powerful instruments allow the cores to be analysed rapidly with virtually no sample preparation. They can record along-core variations for many elements in the Periodic Table from Al to U and detection limits down to a few ppm can be achieved in favourable conditions depending on the acquisition dwell time.

In urban environments, where the majority of the human population lives, air pollution is a major threat to human health. In many countries and regions of the world, this has led to the implementation of regulations to control the emissions of air pollutants and limits for the allowed concentrations of different types of air pollutants. The limits are set at levels at which harm to the health may occur if the limits are exceeded. One of these pollutants is aerosol particles. In most cases, the environmental quality standards limit is set to a certain mass concentration of particles of a certain size.

Scientific studies of artworks are an important practice in many institutions dedicated to the study and protection of cultural heritage. Applied physics and chemistry provide the scientific data necessary to characterise and understand the origin, the degradation processes and the environment in which the artwork was created or has existed.

One of the dangerous kinds of pollution in aquatic systems is due to the dumping of materials containing heavy metals. Hence, the monitoring of heavy metals in aqueous samples is becoming increasingly important. Normally, metal concentrations in water are in the ng L^–1 range, and the analytical procedures used for their determination are usually based on Anodic Stripping Voltametry (ASV) and Atomic Spectrometry, including Electrothermal Atomic Absorption Spectrometry (ETAAS), Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS). However, the direct analysis of some complex environmental samples like seawater presents some difficulties, mainly due to the high salinity of the matrix. Therefore, in such cases, a dilution of the sample may be necessary before the analysis, or a preliminary separation and/or preconcentration step may be required to eliminate interferences and/or to improve detection limits for metals in the low µg L^–1 range. Moreover, when the analysis is performed by using solid sorbents followed by spectrophotometric techniques, an additional elution step after the preconcentration procedure is necessary to recover the species in an appropriate medium.