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The up-conversion emission of Nd 3+ , Sm 3+ and Er 3+ has been studied in a new halogenoantimonite glass with the chemical composition 80 Sb 2 O 3 -10 ZnBr 2 -10 KCl. Doping concentration was 0.2 mol% of lanthanide (Ln) ions. Rare earths were introduced as fluorides LnF 3 that were further converted into oxides. Main physical properties of base glass were measured, including density, thermal expansion, characteristic temperatures, refractive index and optical transmission. The amount of residual hydroxyls was calculated from the OH absorption band around 3000 nm. The recorded up-conversion emission lines are λ em = 536 nm for Nd 3+ pumped at 805 nm; λ em = 563 nm, 600 nm, 631 nm and 645 nm for Sm 3+ pumped at 945 nm; λ em = 531 nm for Er 3+ pumped at 798 nm. Co-doped glass (0.1 Yb 3+ + 0.1 Er 3+ ) pumped at 980 nm has three emission lines at 524 nm, 545 nm and 650 nm. Corresponding transitions have been identified and the mechanisms ruling the up-conversion process is discussed. They include excited state absorption (ESA), energy transfer (ET) cooperative energy transfer (CET), emission assisted by phonon (EAP), multiphonon relaxation (MR) and cross-relaxation (CR).

International audienceThe unconventional Heavy Metal Oxide Glasses (HMOG) are characterized by a low phonon energy, large infrared range transmission, high refractive index and nonlinear optical properties. Ternary glasses have been synthesized and studied in the Sb2O3– MoO3-ZnCl2 system. Further, the glass formation compositional limits are reported and some glass samples with the formula: (90-x)Sb2O3 -xMoO3–10 ZnCl2 (10 ≤ x ≤ 50, mole%) were elaborated. Thermal properties have been measured and indicating that the glass transition temperature decreases with increasing proportions of molybdenum oxide. The evolution of density, microhardness and elastic modulus has been studied as functions of parameter x and Raman spectra measurements have been shown the partial conversion of MoO6 octahedral units into MoO4 tetrahedral

In this study, we are interested in a preliminary characterization of the NV10 steel for the thermochemical treatment. A spectral analysis was done to determine the chemical composition of two NV10 nuances rich and poor in micro-alloying elements. Metallographic characterization allows us to examine the structures and the evaluation of the mean grain diameter. XRD is introduced a supplementary basis for the study of the structure the hardness measurements have been developed in addition to the impact tests at low temperature and traction in both directions of the transverse and longitudinal rolling.