A5002679125- X-ray Spectroscopy and Fluorescence Analysis
- Electron and X-Ray Spectroscopy Techniques
- Nuclear Physics and Applications
- Radiation Therapy and Dosimetry
- Ion-surface interactions and analysis
- Advanced Radiotherapy Techniques
- Air Quality and Health Impacts
- X-ray Diffraction in Crystallography
- NMR spectroscopy and applications
- Radiopharmaceutical Chemistry and Applications
- Characterization and Applications of Magnetic Nanoparticles
- Radiation Shielding Materials Analysis
- Advanced NMR Techniques and Applications
- Radioactivity and Radon Measurements
- Particle Detector Development and Performance
- Renal and related cancers
- Water Quality and Pollution Assessment
- Nanoparticle-Based Drug Delivery
- Thermochemical Biomass Conversion Processes
- Physics of Superconductivity and Magnetism
- Climate Change and Health Impacts
- Coal Properties and Utilization
- Phosphorus compounds and reactions
- Superconducting and THz Device Technology
- Granular flow and fluidized beds
University of Lisbon
2007-2019
Instituto Politécnico de Lisboa
2008-2019
Institut de Radioprotection et de Sûreté Nucléaire
2015-2016
Instituto Superior Técnico
2008-2016
TARH (Portugal)
2011
University of Coimbra
1999
Geant4 is a software toolkit for the simulation of passage particles through matter. It used by large number experiments and projects in variety application domains, including high energy physics, astrophysics space science, medical physics radiation protection. Over past several years, major changes have been made to order accommodate needs these user communities, efficiently exploit growth computing power available advances technology. The adaptation multithreading, detector modeling...
Abstract In 1970s, Basbas et al. (Phys. Rev. A 1973, 7, 983; Phys. 1978, 17, 1655) rose the possibility that PWBA ionisation cross‐sections could be expressed in terms of a universal cross‐section. Starting from ECPSSR and reproducing approach, curve can displayed against reduced ion velocity, but data are too widespread to allow for proper polynomial fit. present work, approach was revised plotted rescaled, eliminating most spread generating practice cross‐section curve. this screening...
Abstract Particle‐induced X‐ray emission is a well‐known technique able to provide information on absolute amounts of chemical elements present in samples, even if very small amounts. Solid state as well effects are known exist, and affect results, but assumed be second‐order until recently only experimentally accessible high‐resolution Wavelegth Dispersive Spectrometer (WDS) systems. Microcalorimeter‐based energy‐dispersive detector systems, which became commercially available recently, may...
The most recent upgrades of the electromagnetic (EM) physics “standard” and “low energy” sub-libraries general purpose Geant4 Monte Carlo simulation toolkit are described. These relevant to different application domains including high energy physics, medical space science. Validation results presented discussed.
The calculation of ionisation cross‐sections induced by H + and He 2+ ions in efficient ways for inclusion simulation programmes to determine the X‐ray intensities is still extremely useful, spite significant computer power available nowadays. Particle‐induced emission studies have been mostly carried out using K‐shell L‐shell emission. However, new microcalorimeter detection systems will make M‐shell higher shell data increasingly important. Quantification require one be able compute...
Until 2008, high-resolution particle-induced x-ray emission (HR-PIXE) work used mostly wavelength dispersive spectrometers and aimed at fundamental problems application demonstrations. The method was hardly for applications in general, due to the small energy window solid angle of most equipment. In last 14 years, a few facts pushed HR-PIXE out beyond this framework. Here, we focus on developments following observation relative yield ion dependence (RYIED) effects transitions same sub-shell,...
The self-consistent Ion Beam Analysis (IBA) of cultural heritage samples using the external beam is technically demanding. We report on calibration an analysis glass from Rosslyn Chapel where interest will ultimately be in full characterisation weathered glass. Such requires a comprehensive Total-IBA approach p-PIGE and He-PIXE to obtain "bulk" surface Na, with H-PIXE/EBS for multielemental depth profiling 10 μm He-PIXE/EBS higher resolution near surface; also two PIXE detectors as usual...
Abstract Particle induced X‐ray emission (PIXE) analysis is generally accepted to be a depth insensitive technique and most of the work up until recently has been oriented in‐depth homogeneous samples. Up recently, multilayer targets were normally looked upon as source problems, implying limitation qualitative or semi‐quantitative approaches. The growing need analyse layered having complex structures close Z elements, which provide unsolvable Rutherford backscattering spectrometry (RBS)...
Recently, the authors have presented experimental evidences that for some energy windows, proton‐induced W L shell X‐rays intensity ratios of transitions to 1 subshell depend on ion beam and chemical species even after known matrix effects are subtracted. These results, which put in question assumption invariance relative X‐ray same atomic subshells, further exploited this work, where more data three different compounds (W, Li 2 WO 4 P O 5 .24WO 3 . x H O) followed by a detailed study using...
Superparamagnetic nanoparticles are widely used as contrast agents for magnetic resonance imaging. We present the Proton Nuclear Magnetic Resonance Dispersion curves colloidal suspension of iron oxide agents. The systems studied composed two different sizes, 80–150 nm dextran coated and 300–400 silicon coated. Previous studies show that longitudinal relaxation time dispersion a function proton Larmor frequency is not easily obtained aqueous diameter nanoparticles. this system over broad...