Publications by authors named "B Vekemans"
Article Synopsis
- Researchers studied tiny rock fragments from asteroid Ryugu using high-energy X-ray fluorescence to analyze their elemental distribution and composition at a microscopic level.
- Samples were collected by the JAXA Hayabusa2 mission, ensuring they remained uncontaminated by Earth's atmosphere during storage and transport.
- The study found significant enrichments of rare earth elements (REE) in certain minerals, particularly apatite, with varying levels of enrichment in other minerals like dolomite and the overall rock matrices.
Article Synopsis
- Samples from the carbonaceous asteroid Ryugu, collected by the Hayabusa2 spacecraft, show evidence of carbon dioxide-bearing water inclusions in a pyrrhotite crystal, suggesting its parent asteroid formed in the outer Solar System.
- The analyzed samples contain few high-temperature materials like chondrules, yet are abundant in low-temperature formation products like phyllosilicates and carbonates, indicating aqueous alteration in a low temperature, high pH environment.
- Numerical simulations reveal that Ryugu's parent body likely formed about 2 million years after the Solar System began to develop, based on the mineralogical and physical properties of the samples.
Article Synopsis
- The study presents a nondestructive method using wavelength-dispersive X-ray fluorescence spectroscopy (WD-XRF) to measure rare earth elements (REE) in unique geological samples without damaging them.
- This technique can detect REE at sensitivity levels down to 0.50 ppm and resolves closely spaced X-ray lines better than energy dispersive methods, particularly in the presence of transition metals.
- The optimized method is particularly useful for analyzing inclusions in deep Earth diamonds, providing valuable insights into elemental composition and the Earth's role in global carbon and fluid cycles.
At the French synchrotron facility SOLEIL, a new X-ray imaging facility PUMA (Photons Utilisés pour les Matériaux Anciens) has been made available to scientific communities studying materials from cultural heritage. This new instrument aims to achieve 2D and 3D imaging with microscopic resolution, applying different analytical techniques including X-ray fluorescence spectroscopy (XRF), X-ray absorption spectroscopy (XAS), X-ray diffraction and phase-contrast imaging. In order to discover its capabilities a detailed analytical characterization of this beamline as an analytical and imaging tool is deemed necessary.
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- A study used advanced X-ray spectroscopy techniques to analyze how earthworms accumulate arsenic (As) when exposed to polluted soils with varying arsenic levels.
- After a 14-day exposure, researchers examined As distribution in the earthworms, confirming high accumulation in their body and coelomic fluid using techniques like micro-X-ray fluorescence spectroscopy and XRF-computed tomography.
- The findings revealed a strong correlation between arsenic levels in the earthworm's body and coelomic fluid, suggesting that measuring As in the coelomic fluid can effectively indicate arsenic availability in contaminated soils, which aids in assessing environmental risks.