Results 41 to 50 of about 58,492 (234)

Monte Carlo simulation of positronium thermalization in gases [PDF]

Hemijska Industrija, 2010
In this paper we present the results of Monte Carlo simulations of positronium (Ps) swarm thermalization in helium (He) and water vapour. We have investigated the temporal evolution of energy and spatial parameters of the swarm and their sensitivity to ...
Marjanović Srđan D., Šuvakov Milovan
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Surfaces of colloidal PbSe nanocrystals probed by thin-film positron annihilation spectroscopy

APL Materials, 2013
Positron annihilation lifetime spectroscopy and positron-electron momentum density (PEMD) studies on multilayers of PbSe nanocrystals (NCs), supported by transmission electron microscopy, show that positrons are strongly trapped at NC surfaces, where ...
L. Chai, W. Al-Sawai, Y. Gao, A. J. Houtepen, P. E. Mijnarends, B. Barbiellini, H. Schut, L. C. van Schaarenburg, M. A. van Huis, L. Ravelli, W. Egger, S. Kaprzyk, A. Bansil, S. W. H. Eijt   +13 more
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Au/GaAs interface annealing study by positron-lifetime spectroscopy [PDF]

, 1995
Structural changes of annealed Au contacts on semi-insulating GaAs have been observed by conventional positron lifetime-spectroscopy in which a significant fraction of positrons are drifted from a Na22 source to the contact by an electric field.
Beling, CD, Fung, S, Panda, BK, Shan, YY, Wang, YY   +4 more
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Kinetics of natural aging in Al-Mg-Si alloys studied by positron annihilation lifetime spectroscopy

, 2011
The process of natural aging in pure ternary Al-Mg-Si alloys was studied by positron annihilation lifetime spectroscopy in real time in order to clarify the sequence and kinetics of clustering and precipitation.
Banhart, J., Chang, C. S. T., Hill, A. J., Lay, M. D. H.   +3 more
core   +1 more source

PALS investigations of free volumes thermal expansion of J-PET plastic scintillator synthesized in polystyrene matrix [PDF]

, 2015
The polystyrene dopped with 2,5-diphenyloxazole as a primary fluor and 2-(4-styrylphenyl)benzoxazole as a wavelength shifter, prepared as a plastic scintillator was investigated using positronium probe in wide range of temperatures from 123 to 423 K ...
Bednarski, T., Białas, P., Czerwiński, E., Gajos, A., Gorgol, M., Jasińska, B., Kamińska, D., Kapłon, Ł., Kochanowski, A., Korcyl, G., Kowalski, P., Kozik, T., Krzemień, W., Kubicz, E., Moskal, P., Niedźwiecki, S., Pałka, M., Raczyński, L., Rudy, Z., Rundel, O., Sharma, N. G., Silarski, M., Strzelecki, A., Słomski, A., Wieczorek, A., Wiślicki, W., Zgardzińska, B., Zieliński, M.   +27 more
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Positron lifetime study of ion-irradiated tungsten: Ion type and dose effects

Nuclear Materials and Energy
Polycrystalline recrystallized tungsten samples were irradiated with 7.5 MeV Si ions and 9 MeV Cu ions to three different damage levels (0.01, 0.1, 0.5 dpa at 200 nm depth) at 295 K.
B. Wieluńska-Kuś, M. Dickmann, W. Egger, M. Zibrov, Ł. Ciupiński   +4 more
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Principles of positron porosimetry

Nukleonika, 2015
The paper deals with positron porosimetry (PP), which is based on positron annihilation lifetime spectroscopy (PALS). The numerical analysis of positron lifetime spectra for PP is more demanding than in most of other applications of PALS.
Zaleski Radosław
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Inverse change in positron lifetimes of vacancies in tungsten by binding of interstitial impurity atoms to a vacancy: A first-principles study

Nuclear Materials and Energy, 2023
First-principles calculations related to defect complexes formed from a monovacancy and multiple interstitial impurity atoms (hydrogen, carbon, nitrogen, and oxygen atoms) in tungsten were performed.
Atsushi Yabuuchi
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Mathematical modeling of elementary trapping-reduction processes in positron annihilation lifetime spectroscopy: methodology of Ps-to-positron trapping conversion [PDF]

, 2017
Methodological possibilities of positron annihilation lifetime (PAL) spectroscopy in application to nanostructurized substances treated within three-term fitting procedure are reconsidered to parameterize their atomic-deficient structural arrangement. In
Yaroslav Shpotyuk, J. Cebulski, A. Ingram, O. Shpotyuk   +3 more
openalex   +2 more sources

Positron Annihilation Spectroscopy in Materials and Technical Details of Measurement Systems [PDF]

فصلنامه علوم و فناوری فضایی, 2013
Being a very powerful method, Positron Annihilation Spectroscopy (PAS) has been widely used for investigation of defects type and concentration in materials in recent years.
A. A. Mehmandoost-Khajeh-Dad, M. Khaghani, M. Jafarzadeh-Khatibani   +2 more
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