Positron Annihilation
Gas permeation and positron annihilation lifetime spectroscopy of poly(ether imides) containing main chain ethylene oxide segments
... Numerous studies have shown the correlation between positron annihilation and gas transport (42-44). In poly(ether imides)s, the PALS gives rise to a long-lived component, which is a consequence of ...
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Monte Carlo Simulation and a Review of the Physics of the Positron Annihilation Process in PET
... the positron annihilation process was carried ...the positron annihilation process degrades the spa- tial resolution of the PET imaging system, because each point source or voxel of the imaged ...
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Positron Annihilation Spectroscopy and Electrochemical Impedance Spectroscopy Studies of Polyurethane-Urea Hybrid Coatings
... by positron annihilation spectroscopy and electrochemical impedance spectroscopy ...by positron annihilation spectroscopy and EIS were in good agreement, suggesting that there is a direct ...
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Positron Annihilation in the Milky Way: Searching for the source of Galactic antimatter
... the positron spends in the collisional and collisionless regime, is evaluated to be „ 40 ´ 160 ...of positron annihilation gamma-rays: Positrons born into the hot, „ 10 7 K plasma at the base of the ...
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Positron Annihilation Spectroscopy to Characterize Irradiation Induced Vacancy Type Defects in Materials for Nuclear Fission and Fusion
... Positron annihilation spectroscopy (PAS) is a well-established technique to characterize materials ...charge, positron is sensitive to the local variations of the Coulomb potential in ...electron ...
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Explanation of the Hidden Variables in the Electron Positron Annihilation Process in Terms of the Quantum Entanglement and the Conservation of Flux Quantum
... electron-positron annihilation process by using the conservation of the spin angular momentum and the con- servation of quantum flux which can be replaced by the conservation of the magnetic ...
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Non Destructive Evaluation of Fatigue Damage in Type 316 Stainless Steel Using Positron Annihilation Lineshape Analysis
... of positron annihilation lineshape analysis Figure 9 shows the relationship between the fatigue life ra- tio and the S-parameter for all stress-controlled fatigue speci- mens subjected to stress amplitude ...
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Role of the Reference Frame in Angular Photon Distribution at Electron Positron Annihilation
... The reasons of angular photon distribution occurrence at electron-positron annihilation are con- sidered. It is shown that angular photon distribution is consequence of Doppler’s effect in the re- ference ...
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Positron annihilation study of structural relaxation and crystallization of glassified milk fat
... the positron annihilation technique (PAT). Positron spectro- scopy is an effective tool for the studies of free volume variations in polymers and molecular ...substances. Annihilation of ...
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Direct, Resonant Production of States with Positive Charge Conjugation in Electron-Positron Annihilation
... for experiments at electron-positron colliders from the beginning. Great emphasis has been put on charmonium and bottomonium ground- and excited states. Their production rates are proportional to the widths of ...
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Microstructural Investigation of PM 355 Nuclear Track Detector Subjected to Low Dose Gamma Irradiation: A Positron Annihilation Lifetime Study
... in Positron Annihilation Lifetime Spectroscopy,” Journal of Physics: Condensed Matter, ...Crystallinities: Positron Lifetime, Density, and X-Ray Studies,” Journal of Polymer Science Part B: Polymer ...
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Theoretical Studies of Positron Annihilation in Aluminum Bismuth Alloy
... annihilating positron-electron pairs ...the positron annihilation rate in the low-momentum regime, thus giving rise to shorter positron lifetimes than the experimental ...
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Effect of Annealing Temperature on Prepared Nanoparticles Li Ferrite Using Positron Annihilation Lifetime Technique
... A positron implanted in this type of materials can have different lifetimes depending on the electron density at the annihilation ...Thus, positron lifetime spectroscopy can give information about ...
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Metal Semiconductor Interfaces Investigated by Positron Annihilation Spectroscopy
... of positron annihilation data of different metal-semiconductor structures reveals the presence of positron absorbing interfaces, and they do not allow thermal positrons diffusing randomly or under ...
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Investigation of Positron Annihilation Diffusion Length in Gallium Nitride
... for positron diffusion length in Gallium nitride less than 60 nm where the expected values in semiconductors are in the range of 200 nm to 300 ...study, positron annihilation experimental results for ...
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Structural analysis of IPC zeolites and related materials using positron annihilation spectroscopy and high resolution argon adsorption
... Another technique that has been applied for the analysis of pore networks in zeolites is that of positron annihilation spectroscopy (PALS). This technique operates on the basis that metastable ...
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Development of Positron Annihilation Spectroscopy Techniques Applied to Damaged Polyimide Film
... A new suggestion is put forward by Dirac in 1931 in the paper Quantised Singularities in the Electromagnetic Field. Negative energy states must not be protons, thus this is a new particle, yet to be observed: “A hole, if ...
201
Design and Implementation of a Digital Positron Annihilation Lifetime Spectrometer for Measurements in Graphite
... each positron absorbed in the test material and its supporting ...the positron from each nucleus‟s decay. The end of the positron‟s lifetime is marked by the detection of its ...MeV ...
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Positron Annihilation lifetime studies of inorganic materials using a new positron beamline
... Within the bulk, trapping sites are created by defects in the material due to impurities or structural anomalies. Here, the examples given will use a simple cubic lattice to clearly illustrate the defects. The first type ...
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Studies on General Kinematic Effects of Hadrons in Electron Positron Annihilation at High Energy
... The initial particles of e e annihilation reactions (i.e. positive and negative electrons) are all leptons without internal structure, and the corresponding background is relatively clean. In present, China is ...
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