[en] Aromatic molecular fluorescence in condensed media is today much more than a phenomenon. As well as providing a tool to research underlying molecular photophysics, it provides unique properties in terms of sensitivity and timescales for studying and using reactions and kinetics across a whole range of disciplines. In this short perspective, I will chart some of the milestones and highlights in the evolution of modern day fluorescence from the viewpoint of instrumentation and techniques applied to biomolecular science. Along the way I will note some present obstacles to progress, challenges and future opportunities. (perspective)

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[en] The fluorimetric instrumentation and analysis method for uranium determination in geological, biological and water samples are explained. Methods and techniques used for uranium analysis are briefly summarized. Factors influencing the analysis, such as, (interference, quenching effect, impurities, acids, fusion agents) and how-to-overcome them are reported. The digestion procedures and the utilizing of the following methods (extraction, internal standard, extrapolation) for the determination of uranium in different kinds of samples by fluorimetry are investigated. In addition to that, the way of operating instrument, preparing the calibration graphs and finally the evaluation of the results are explained. (author). 12 refs., 12 figs., 7 tabs

[en] The use of the elemental composition, determined by energy dispersive X-ray fluorescence (EDXRF), to characterize ancient and modern papyrus and parchment, and newspaper from three different years is reported. The concentrations of S, Cl, K, Ca, Ti, Mn, Fe, Cu, Zn, Ga, As, Br, Rb, Sr, Ba and Pb were determined in these samples in order to proceed to its characterization. From this work, we can conclude that the obtained results allow distinguishing modern and ancient documents by its elemental amount. It was observed, with few exceptions, that the modern samples present lower elemental concentration than the older ones. Furthermore, in the newspaper samples the number of detected elements depends on the newspaper's age, and decreases from the oldest (1919) to the most recent (2005). X-ray fluorescence spectrometry is a good elemental technique with the main advantage of being non-destructive, which makes it the perfect tool for the elemental analysis of cultural heritage

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[en] The photophysical properties of pyronin B (PyB) and pyronin Y (PyY) in reverse micelles formed with water/sodium bis (2-ethyl-1-hexyl) sulfosuccinate (AOT)/n-heptane were investigated by UV–vis absorption, steady-state and time-resolved fluorescence spectroscopy techniques. This study was carried out a wide range of reverse micelle sizes, with hydrodynamic radii ranging from 1.85 to 9.38 nm. Significant photophysical parameters as band shifts, fluorescence quantum yields and fluorescence lifetimes were determined to understand how photophysical and spectroscopic features of the dye compounds were affected by the variation of reverse micelle sizes. In this regard, control of reverse micelle size by changing W₀, the molar ratio of water to surfactant, allowed tuning the photophysical properties of the dyes in organic solvent via reverse micelle. Non-fluorescent H-aggregates of pyronin dyes were observed for the smaller reverse micelles whereas an increase in the reverse micelle size induced an increment in the amount of dye monomers instead of dye aggregates. Thus, the fluorescence intensities of the dyes were improved by increasing W₀ due to the predomination of the fluorescent dye monomers. As a result, the fluorescence quantum yields also increased. The fluorescence lifetimes of the dyes in the reverse micelles were determined by the time-resolved fluorescence decay studies. Evaluation of the fluorescence lifetimes calculated for pyronin dyes in the reverse micelles showed that the size of reverse micelle affected the fluorescence lifetimes of pyronin dyes. -- Highlights: • The photophysical properties of pyronin dyes were examined by spectroscopic techniques. • Optical properties of the dyes were tuned by changing of W₀ values. • The fluorescence lifetime and quantum yield values of the dyes in reverse micelles were discussed

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[en] We describe the test system built to perform the acceptance tests of more than 11 000 photomultiplier (PMT) tubes employed in the fluorescence detector of the Pierre Auger Observatory. The results obtained on the properties of the PMT are presented and discussed

[en] Short communication