Indoor radon concentrations were determined with the use of track-etched detectors and two monitors, both for radon and one for the decay products, in various regions of Greece. Until now, 1137 dwellings have been measured. Some factors, that influence the radon concentration in dwellings, are discussed in this paper. The factors, used in this analysis, were derived from the householders’ answe...

Résumé — Polyacrylamides sulfonés modifiés hydrophobes pour la RAH (IOR) : corrélations entre le caractère associatif et l’injectivité en régime dilué — Nous présentons de nouvelles corrélations expérimentales entre l’injectivité dans des membranes de polycarbonate et le caractère associatif de Polymères Hydrosolubles Modifiés Hydrophobes (PHMH) ayant des squelettes de polyacrylamide sulfoné (P...

The stable one-time tuning of silicon-photonic directional couplers, over a broad range of coupling ratios, is achieved through the selective photo-removal of an upper cladding layer of chalcogenide glass. Analysis shows that the coupling coefficient per unit length between two parallel fully-etched silicon waveguides may be changed by 45%. The power coupling ratio of a 50 µm-long directional c...

It is well established that the bulk etch rates for solid state nuclear track detectors are a ected by the concentration and the temperature of the etchant. Recently, we found that the bulk etch rate for the LR 115 detector to be a ected by stirring during etching. In the present work, the e ects of stirring on the bulk etch rate of the CR-39 detector is investigated. One set of sample was etch...

The aim of the study was to investigate the contribution of secondary particles (mainly neutrons) in producing radiation damage to electronic devices and to astronaut-dose onboard of the International Space Station (ISS). Especially: • To optimize solid state nuclear track detector (SSNTD) assemblies, have been used earlier for neutron dosimetry around nuclear facilities [1,2], for space dosime...

The latest advances in the development of a fluorescent nuclear track detector (FNTD) for neutron and heavy charged particle dosimetry are described and compared with CR-39 plastic nuclear etched track detectors (PNTDs). The technique combines a new luminescent aluminium oxide single crystal detector (Al(2)O(3):C,Mg) with an imaging technique based on laser scanning and confocal fluorescence de...

The radial distribution of track density on a solid-state nuclear track detector inside a diffusion chamber is a function of the fraction f of Po decay before deposition. In the present work, procedures are proposed to determine f experimentally by determining the track density distribution on an LR115 detector in a diffusion chamber. First, a relatively tall diffusion chamber, with a height of...

The effect of pre-gamma irradiation on track density, bulk etch rate and light absorbance in CR-39 was investigated. CR-39 detectors were irradiated with gamma doses over a range of 0 to 280 kGy (0 to 28 Mrad). The detectors were overlaid with 0.77 mm of polyethylene and exposed to a known fluence of 252Cf spontaneous fission neutrons. All detectors were then etched in 6.25N sodium hydroxide so...

A fully three-dimensional finite-difference time domain numerical model is presented for calculating the out-of-plane radiation loss in photonic-crystal slab waveguides. The propagation loss of a single-line defect waveguide in triangular-lattice photonic crystals is calculated for suspended-membrane, oxidized-lower-cladding, and deeply etched structures. The results show that low-loss waveguid...