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Two-step gamma cascades (TSCs) following the radiative capture of thermal neutrons in 77Se were measured at the research reactor at Řež near Prague. Results on photon strength functions (PSFs) of 78Se, obtained from comparison of experimental TSC spectra with outcomes of simulations under different assumptions about level density and PSFs using the DICEBOX algorithm, are presented. The main attention is paid to possible manifestation of the pygmy resonance observed recently in this nucleus in the nuclear resonance fluorescence measurement and low-energy PSF enhancement observed in Oslo-type experiments for all A ≲ 100 nuclei.

In this work, two thin hybrid composites based on organic-like fullerenes (bucky balls C 60 ) and inorganic compounds of lithium cobalt oxide (LiCoO 2 ) were prepared. The composites were synthesized by a combined method of ion sputtering and evaporation. The prepared samples were sandwiched between 2 gold electrodes and subjected to charging at an applied small voltage. After each charging process, the samples were analyzed using two appropriate methods—the surface morphology was monitored using AFM (Atomic Force Microscopy), and lithium depth concentration profiles were measured using NDP (Neutron Depth Profiling). The results of the measurements showed that both types of composite experienced significant changes both in the surface morphology and especially in the depth distribution of lithium. The test confirmed the expectation that the unusual hybrid combination of organic and inorganic phases is electrochemically active and exhibits characteristics of Li battery behavior.

Activation detectors are very often used for determination of the neutron fluence in reactor dosimetry. However, there are few disadvantages concerning these detectors; it is the demand of the knowledge of the irradiation history and a loss of information due to a radioactive decay in time. Transmutation detectors TMD could be a solution in this case. The transmutation detectors are materials in which stable or long-lived nuclides are produced by nuclear reactions with neutrons. From a measurement of concentration of these nuclides, neutron fluence can be evaluated regardless of the cooling time.

In this work, two thin hybrid composites based on organic-like fullerenes (bucky balls C.sub.60) and inorganic compounds of lithium cobalt oxide (LiCoO.sub.2) were prepared. The composites were synthesized by a combined method of ion sputtering and evaporation. The prepared samples were sandwiched between 2 gold electrodes and subjected to charging at an applied small voltage. After each charging process, the samples were analyzed using two appropriate methods-the surface morphology was monitored using AFM (Atomic Force Microscopy), and lithium depth concentration profiles were measured using NDP (Neutron Depth Profiling). The results of the measurements showed that both types of composite experienced significant changes both in the surface morphology and especially in the depth distribution of lithium. The test confirmed the expectation that the unusual hybrid combination of organic and inorganic phases is electrochemically active and exhibits characteristics of Li battery behavior.

The reduction of graphite oxide is one of the most important reactions in the production of graphene in gram quantities. The mechanisms of these widely used reactions are poorly understood. The mechanism of the chemical reduction of two different graphite oxides prepared by the chlorate (Hofmann method) and permanganate methods (Hummers method) has been investigated. Three different reduction agents, lithium tetrahydridoaluminate, sodium tetrahydridoborate, and lithium tetrahydridoborate, as well as their deuterated counterparts, were used for the reduction of graphite oxide. Reduced graphite oxides were analyzed by scanning electron microscopy, energy‐dispersive spectroscopy, elemental combustion analysis, Raman spectroscopy, high‐resolution X‐ray photoelectron spectroscopy, and simultaneous thermal analysis. The concentration of boron incorporated into graphene was measured by prompt gamma activation analysis. Rutherford back‐scattering spectroscopy and elastic recoil detection analysis were used for the determination of the elemental composition, including deuterium concentration, as evidence of CH bond formation. Unraveling reduction: The mechanism of graphite oxide reduction is resolved by analyzing complex deuterides and hydrides. Reduction leads to the formation of hydroxy groups with simultaneous hydrogenation of reduced carbon atoms (see figure).