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[en] Highlights: • OLi3O− is designed by interaction of OLi3 superalkali with O atom. • OLi3O− is more basic than LiO−, the strongest base known to date. • OLi3O− is kinetically and thermodynamically stable. • OLi3O− can be synthesized by the gas phase reaction of Li2O and LiO−. LiO− (proton affinity = 1785 kJ/mol) is the strongest base reported in the literature, followed by CH3− (proton affinity = 1743 kJ/mol). Using ab initio and DFT calculations, we propose the design of a novel base OLi3O−, by interacting OLi3 superalkali with O atom, which is even more basic than LiO−. The proton affinity of OLi3O− isomers lies in the range 1803–1928 kJ/mol. This strongest base is kinetically and thermodynamically stable, which can be synthesized by reacting Li2O with LiO− at least in gas phase. This study may provide suitable path to the experimentalists to further explore this novel species.
[en] Thermochemical quantities for the formation of Li2SnO3(s) have been determined by the third-law treatment on the basis of the reported partial vapor pressures of Li(g), O2(g), LiO(g), Li2O(g), and SnO(g) in equilibrium with Li2SnO3(s). The enthalpy, Gibbs energy and entropy of formation from the elements are ΔfH298 (Li2SnO3,s)=-(1322±13) kJ mol-1, ΔfG298 (Li2SnO3,s)=-(1225±13) kJ mol-1 and ΔfS298 (Li2SnO3,s)=-(326±62) J K-1mol-1, respectively. A value for the enthalpy of formation from the constituent oxides Li2O(s) and SnO2(s) has also been obtained: ΔfoxH298 (Li2SnO3,s)=-(143±13) kJ mol-1. In the Li2O-SnO2 system, the thermochemical stability of Li2SnO3(s) is probably better than that of Li8SnO6(s). Comparison of these results was also made with those of other lithium-containing complex oxides. (orig.)
[en] An analysis of the different surface reactions taking place in Li2O was performed in order to determine whether adsorption and desorption of tritium are first or second order reactions. Data from BEATRIX-II Phase I and CRITIC-I were used as basis for calculations. It was found that only second order adsorption/desorption on the surface of Li2O can predict the tritium behavior observed experimentally
[en] Tritium release from the candidate ceramic materials, Li2O, LiA102, Li2SiO3, Li4SiO4 and Li2ZrO3, is being investigated in many blanket programs. Factors that affect tritium release from the ceramic into the helium sweep gas stream include operating temperature, ceramic microstructure, tritium transport and solubility in the solid. A review is presented of the material properties studied and of the irradiation programs and the results are summarized. The ceramic breeder blanket concept is briefly reviewed
[en] Lithium oxide as a fusion blanket material has neutronic advantages but various design limitations. The study was undertaken to investigate the design implications, to demonstrate how the limitations can be overcome and to provide guidance for future development. The study included lithium oxide properties, tritium control, coolant chemistry, blanket engineering and blanket neutronics. (author)
[en] The energy of preference of ion Li+ to octahedral position in the rock salt structure, E = -10 kcal/g-ion, was estimated from heats of formation of LiFeO2, LiAlO2 and Li2TiO3. The heats of formation of the LiVO2, LiCrOL2, LiCoO2, and LiMnO2 compounds were calculated from the corresponding oxides (-13--m14 kcal/mole)
[en] The release of tritium from neutron irradiated spherical samples of single crystal Li2O was measured by isothermal annealing experiments. The release is shown to be controlled by diffusion of tritium in the solid under appropriate experimental conditions. Deviations from solely diffusion controlled release were observed when traces of water were present in the He-purge gas used in the experiments. (orig./RW)
[en] We present an analytical theory for the large-phase-shift, thick Z-scan transmittance, which could be applied to a wide range of medium thickness from the thin sample limit to a thick medium and to small and large nonlinear phase shifts. The theoretical results were experimentally verified for in photorefractive LiNbO3:Fe crystals by using two kinds of closed-aperture Z-scan measurements with a Ti-sapphire laser source (λ = 810 nm): (1) sample-thickness-dependent Z-scans with thin and thick samples and (2) normalized-thickness-factor-dependent Z-scans with different external lenses having different focal lengths in the same thick LiNbO3:Fe crystal.
[en] The MCMB-Li4Ti5O12 with core-shell structure was prepared by sol-gel process to improve low cycle capability of MCMB in this study. The electrochemical characteristics were investigated for hybrid capacitor using MCMB-Li4Ti5O12 as the negative electrode and LiMn2O4, Active carbon fiber as the positive electrode. The electrochemical behaviors of hybrid capacitor using organic electrolytes (LiPF6, EC/DMC/EMC) were characterized by charge/discharge, cyclic voltammetry, cycle and impedance tests. The hybrid capacitor using MCMB-Li4Ti5O12/LiMn2O4 electrodes had better capacitance than MCMB hybrid systems and was able to deliver a specific energy with 67 Wh/kg at a specific power of 781 W/kg