Raman spectra of Ag- and Cu- photodoped chalcogenide films

Raman spectra of the chalcogenide vitreous layers (As₄₀S₆₀, As₄₀S₄₀Se₂₀, As₄₀Se₆₀ ) non-doped and photodoped by Ag, Cu were measured. The spectra were analyzed in terms of a molecular model. It was ascertained, that for the spectra of photodoped As₄₀S₆₀, As₄₀S₄₀Se₂₀ layers, the shift of the main bands to the high frequency side and the appearance of the additional scattering bands in the low frequency spectral range are characteristic features. For the spectra of photodoped As₄₀S₆₀ layers, such shift and significant increase in scattering were not observed. Variations in the Raman spectra with photodoping by Ag or Cu are consistent with the supposition concerning normal covalent and coordinative bond formation between metal additives and chalcogen atoms

Nano-sized phase inclusions in As₂S₃ glass, films and fibers based on this glass

In this report, the comparative analysis using Raman spectroscopy of the short-range order in amorphous As₂S₃ films deposited with different evaporation rates, volume glass and fiber based on this glass is presented. With increasing the film deposition rate, their structure becomes more non-uniform as compared to that of glass. Raman spectra excited by laser radiation with energy bigger than the width of the optical gap indicate photomodification of the structure of As₂S₃ glass and fiber based on it

Direct magnetic and surface relief patterning using carbazole-based azopolymer

The results on using of carbazole-based azopolymer layers (Polyepoxypropylcarbazole:Methyl Red with magnetic particles of Fe2SO4) for the recording of 1-D and 2-D surface relief gratings are presented in this report. Morphology study using AFM and MFM of obtained structures has shown their good quality. Surface relief gratings with profile height up to 1.2 µm were obtained during the holographic recording using blue laser. Along with surface relief grating it was shown the direct formation of magnetic relief. Possibility of simultaneous direct fabrication of surface and magnetic relief by optical holographic recording using azopolymer thin films as recording media was shown

Photoinduced structural changes in As₁₀₀₋xSx layers

The present paper is concerned with investigations of photoinduced structural changes in As100-xSx layers. Optical constants of variously treated (virgin, exposed, annealed) samples were determined from optical transmission measurements in the spectral region 400-2500 nm. The energy dependence of refractive index n for variously treated samples was fitted by the Wemple-DiDomenico dispersion relationship and used to estimate the single-oscillator model parameters. It was found, that exposure, as well as annealing leads to the increase in n values over the all investigated spectral region. Compositional dependencies of single-oscillator model parameter Ed (dispersion energy), optical dielectric constant ε(0) show maximum at stoichiometric composition As₄₀S₆₀ and, possibly, weak maximum at As₂₈.₆S₇₁.₄ composition. Changes of the parameters of the single-oscillator model induced by treatment are discussed on the base of photo- and thermally-induced structural changes, which were directly confirmed by Raman scattering measurements. Such photoinduced structural changes provide good etching selectivity of As-S layers in amine based solvents. Intensity dependence of the Raman bands corresponding to the As rich and S rich molecular fragments on exposure time is well described by the exponential decay, which correlates with exponential decay dependence of the etching rate of As₁₀₀₋xSx layers on exposure

Towards a national child and adolescent health strategy in Switzerland: strengthening surveillance to improve prevention and care.

Erworben im Rahmen der Schweizer Nationallizenzen (http://www.nationallizenzen.ch

The development and pilot-testing of a training curriculum in adolescent medicine and health.

PURPOSE: To select and propose a set of knowledge, attitudes, and skills essential for the care of adolescents; to encourage the development of adolescent health multidisciplinary networks; and to set up training programs in as many European countries as possible. METHODS: The curriculum was developed by 16 physicians from 11 European countries with various professional specializations. In line with modern guidelines in medical education, it is a modular, flexible instrument which covers the main teaching areas in the field, such as basic skills (i.e. setting, rights and confidentiality, gender and cultural issues) as well as specific themes (i.e. sexual and reproductive health, eating disorders, chronic conditions). It consists of 17 thematic modules, each containing detailed objectives, learning approaches, examples, and evaluation methods. RESULT: Two international one-week summer schools were used to assess the feasibility and appropriateness of the curriculum. The overall evaluation was good, with most of the items surpassing three on a four-point Likert scale. However, it pointed to several aspects (process and content) which will need to be refined in the future, such as an increase in interactive sessions (role playing), and a better mix of clinical and public health issues