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Article
Cygnus X-3 revealed as a Galactic ultraluminous X-ray source by IXPE
The accretion of matter by compact objects can be inhibited by radiation pressure if the luminosity exceeds a critical value known as the Eddington limit. The discovery of ultraluminous X-ray sources has shown...
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Reference Work Entry In depth
X-ray Polarimetry-Timing
X-ray polarimetry-timing is the characterization of rapid variability in the X-ray polarization degree and angle. As for the case of spectral-timing, it provides causal information valuable for reconstructing ...
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Article
Polyvinylpyrrolidone-nanosized glassy arsenoselenides characterized by complementary Positronics and XRD analysis
Nanostructurization effects, in glassy arsenoselenides g-AsxSe100-x (5 ≤ x ≤ 65) subjected to wet nanomilling in polyvinylpyrrolidone (PVP) water solution, are studied employing the Positronics, an advanced chara...
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Article
X-ray polarization evidence for a 200-year-old flare of Sgr A*
The centre of the Milky Way Galaxy hosts a black hole with a solar mass of about 4 million (Sagittarius A* (Sgr A)) that is very quiescent at present with a luminosity many orders of magnitude below those of acti...
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Living Reference Work Entry In depth
X-ray Polarimetry-Timing
X-ray polarimetry-timing is the characterization of rapid variability in the X-ray polarization degree and angle. As for the case of spectral-timing, it provides causal information valuable for reconstructing ...
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Article
Comparative study of free-volume changes in light-cured (dimeth)acrylate-type dental resin composites affected to artificial aging in dry-air and water-immersed mode
This research is intended to compare degradation processes in light-cured (dimeth)acrylate-type polymer/filler dental composites affected to aging in dry-air and water-immersed mode. The positron annihilation ...
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Article
Towards Precision Measurements of Accreting Black Holes Using X-Ray Reflection Spectroscopy
Relativistic reflection features are commonly observed in the X-ray spectra of accreting black holes. In the presence of high quality data and with the correct astrophysical model, X-ray reflection spectroscop...
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Article
Open AccessThe high energy Universe at ultra-high resolution: the power and promise of X-ray interferometry
We propose the development of X-ray interferometry (XRI), to reveal the Universe at high energies with ultra-high spatial resolution. With baselines which can be accommodated on a single spacecraft, XRI can re...
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Article
Open AccessA polarized view of the hot and violent universe
X-ray polarimetry has long been considered the ‘holy grail’ of X-ray astronomy. Fortunately, after a silence of more than 40 years, the field is now rejuvenating. In fact, an X-ray polarimeter onboard a Cube-s...
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Chapter and Conference Paper
Epoxy Molecular Structure Alteration in Graphene-Epoxy Nanocomposites: Loading Effects
Molecular structure alteration in a polyethylene-polyamine-cured DGEBA-epoxy resin induced by multi-layered graphene nanoplatelets (MLGNPs) have been experimentally studied by broadband dielectric spectroscopy...
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Article
Light-curing effects in acrylic-type dental nanocomposites probed by annihilating positrons: the case of densely monolith ЭCTA-3® restoratives
Photopolymerization volumetric shrinkage in densely monolith dental restorative composites is characterized at the example of ЭCTA-3® composites, employing positron annihilation lifetime (PAL) spectroscopy within...
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Article
Open AccessLight-curing effects in acrylic-type dental nanocomposites probed by annihilating positrons: the case of loosely monolith Dipol® restoratives
The possibility of application of positron annihilation lifetime (PAL) spectroscopy to commercially available dimethacrylate-based dental restorative composites Dipol® (Oksomat-AN Ltd, Ukraine) subjected to ph...
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Article
Multicomponent positron–electron annihilation kinetics in the MgO–Al2O3 ceramics in the frequency domain
Multicomponent positron–electron annihilation kinetics in initially dried (after natural water adsorption and before water treated process) and with following immersion into water MgO–Al2O3 ceramics sintered at d...
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Article
Effect of water adsorption on positron–electron annihilation kinetics in the MgO–Al2O3 ceramics in the frequency domain
Positron–electron annihilation kinetics in the MgO–Al2O3 ceramics sintered at different temperatures (1100, 1200 and 1400 °C) with the following water adsorbtion procedure has been calculated and analyzed in a fr...
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Article
Frequency domain kinetic of positron–electron annihilation in the MgO–Al2O3 spinel-type ceramics
In this work, the kinetic of positron–electron annihilation in the MgO–Al2O3 spinel-type ceramics sintered at different temperatures (1100, 1200 and 1400 °C) has been calculated and analyzed in a frequency domain...
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Article
Accretion in strong field gravity with eXTP
In this paper we describe the potential of the enhanced X-ray Timing and Polarimetry (eXTP) mission for studies related to accretion flows in the strong field gravity regime around both stellar-mass and superm...
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Article
Open AccessMechanochemically driven amorphization of nanostructurized arsenicals, the case of β-As4S4
The amorphization is studied in mechanically activated β-As4S4 using high-energy ball milling in a dry mode with 100–600 min−1 rotational speeds, employing complementary methods of X-ray powder diffraction (XRPD)...
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Article
Open AccessMicrostructure Hierarchical Model of Competitive e+-Ps Trap** in Nanostructurized Substances: from Nanoparticle-Uniform to Nanoparticle-Biased Systems
Microstructure hierarchical model considering the free-volume elements at the level of interacting crystallites (non-spherical approximation) and the agglomerates of these crystallites (spherical approximation...
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Article
Open AccessFree Volume Structure of Acrylic-Type Dental Nanocomposites Tested with Annihilating Positrons
Positron annihilation spectroscopy in lifetime measuring mode exploring conventional fast-fast coincidence ORTEC system is employed to characterize free volume structure of commercially available acrylic-type ...
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Article
Open AccessWater-Vapor Sorption Processes in Nanoporous MgO-Al2O3 Ceramics: the PAL Spectroscopy Study
The water-vapor sorption processes in nanoporous MgO-Al2O3 ceramics are studied with positron annihilation lifetime (PAL) spectroscopy employing positron trap** and positronium (Ps)-decaying modes. It is demons...
