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The measurement of pH in small objects (cells, drops of liquid etc.) using optical fluorescence-based sensors on optical fiber tapers is one of the most widely used optical techniques. In these sensors the diameter of the taper can play important role for collecting fluorescence from tested samples. This paper presents results of experimental measurements of fluorescence intensity of dye sensitive to pH in a solution that is excited by a blue laser. The fluorescence of the dye is collected by a taper tip. The fiber tips were prepared from a graded-index fiber with a core diameter of 50 m. Measurements with taper tips of different diameters have allowed us to estimated a limited tip diameter necessary for collecting any fluorescence form the dye solution on a level of about 5m.

An experimental spectroscopic investigation of 35Al has been performed. The delayed neutron and γ spectra, following the β decay of 35Al, have been measured using the delayed neutron detector array TONNERRE coupled with high efficiency γ detectors. A detailed analysis of such spectra allows one to extract the level schemes of its daughters. These levels are compared with the few previously existing data and shell-model calculations. Based on triple β–γ–n coincidences eight new levels above the neutron separation energy in 34Si were for the first time observed.

The structure of neutron-rich light nuclei around N= 20 and 28 has been investigated at GANIL by means of in-beam gamma-spectroscopy using fragmentation reactions of 36S and 48Ca beams on a Be target. Gamma-decay of relatively high-lying excited states have been measured for the first time in nuclei around 32Mg and 44S. Level schemes are proposed and discussed for a large number of these neutron-rich nuclei around N= 20 and N= 28.

Following mass measurements in the region N= 20 and N= 28, we have studied inelastic nuclear scattering for the nuclei 34Si, 33Al and 32Mg. No evidence for a low-lying shape isomeric 0+state was found in 34Si, and an upper limit for the population cross-section could be established, rendering its existence very unlikely. A new transition was found in 33Al, that is a good candidate for a 2p-2h state and therefore a determination of the 2p-2h gap at N= 20. Inelastic nuclear scattering strongly excites 3-states, as seen in 34Si. A strong transition was found in 32Mg that should correspond to the first 3-in this nucleus, lying very low as compared to theory and systematics in this region.

241Am, 237Np and 129I radioactive targets were irradiated by proton beams with energy 0.66 GeV. The cross- sections of formation of 80, 53 and 86 residual nuclei from 241Am, 237Np and 129I are determined. The experimental results are compared with the theoretical cross-sections calculated by the cascade-evaporation model (CEM).

A software package is proposed for determining cross sections of spallation, fission, or fragmentation by activation methods. Various additions have been made to the method, including correction for single and double escape peaks on the areas of the γ lines for the residual nuclei, and for the dead time of the measurement system, with a proposal for the complete identification of all lines of each nuclide observed on the basis of the internal intensity ratios derived from a nuclear database.

Following mass-measurements in the region N = 20 and N = 28, we have studied inelastic nuclear scattering for the nuclei 34Si, 33Al and 32Mg. No evidence for a low lying shape isomeric 0+ state was found in 34Si, and an upper limit for the population cross section could be established, rendering it's existence very unlikely. A new transition was found in 33Al, that is a good candidate for a 2p-2h state and therefore a determination of the 2p-2h gap at N = 20. Inelastic nuclear scattering strongly excites 3- states, as seen in 34Si. A strong transition was found in 32Mg that should correspond to the first 3- in this nucleus, lying very low as compared to theory and systematics in this region.

Local chemical sensing in living cells by fluorescence methods with submicron spatial resolution is in the scope of biologist because of bringing new information about biochemical processes in living matter [1]. One of the most important monitored variables is pH. Despite of progress of novel submicron probes suitable for in-situ measurement in living cells [1] and biological micro samples [2] still there is a lack off suitable opto-chemical transducers sensitive around pH 5-7 limiting development of novel fluorescence sensors. Moreover, the interaction of the immobilized transducer with the matrix can strongly affect its fluorescence properties. In our contributition the 2',7'-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein (BCECF) fluorescence pH transducer was incorporated into organosols based on tetraethylorthosilicate (TEOS), 3-glycidoxypropyltrimethoxysilane (GPTMS) and 3-aminopropyltriethoxysilane (APTES). Formed organosols were spin-coated onto Pyrex glass substrates and thermally treated at 140°C for 4 hours. Prepared thin layers were exposed to Britton-Robinson buffers with different pH ranging from 4 to 8 pH units. Optical properties of immobilized BCECF were investigated by the mean of absorption and fluorescence spectroscopy Acquired results were compared with the properties of BCECF solutions. It was found that all matrices reduce the sensitivity of the BCECF transducer comparing to the free solution. GPTMS and APTES contained layers exhibited better mechanical properties and increase the solubility of BCECF inside prepared layers comparing to layers prepared from pure TEOS.