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This study presents a simple method for retrieving the effective thermal conductivity of semitransparent glassmelts from measured temperature profiles. Effective thermal conductivity of molten glass at high temperature is an important thermophysical property that affects the glassmelting and forming processes and thus the quality of the final glass products. In semitransparent glassmelts, heat is transferred by both conduction and radiation. In the limiting case of optically thick glassmelts, typically featuring high iron content, thermal radiation can be treated as a diffusion process. The total heat flux can be expressed as the sum of a phononic and a radiative heat fluxes based on Fourier's law. For weakly absorbing glassmelts, the temperature profile may be strongly nonlinear particularly neat container walls due to the contribution from emission and absorption. Steady-state measurement techniques, such as the linear heat flux method, have been developed to measure glassmelt effective thermal conductivity at high temperatures. However, they typically use only three temperatures measurements and assume linear temperature profile in the glassmelt. The new retrieval method addresses these drawbacks particularly for weakly absorbing glassmelts featuring nonlinear temperature profiles. It is demonstrated with experimental data collected for sodalime silicate glasses with iron content ranging from 0.008 to 1.1 wt% and temperatures between 1100°C and 1550°C.

This paper explores the physical mechanisms responsible for experimental observations that led to the definition of "photo-induced hydrogen outgassing of glass". Doped borosilicate glass samples were placed inside an evacuated silica tube and heated in a furnace or by an incandescent lamp. It was observed that hydrogen release from the glass sample was faster and stronger when heated by an incandescent lamp than within furnace. Here, sample and silica tube were modeled as planeparallel slabs exposed to furnace or to lamp thermal radiation. Combined conduction, radiation, and mass transfer were accounted for by solving the one-dimensional transient mass and energy conservation equations along with the steady-state radiative transfer equation. All properties were found in the literature. The experimental observations can be qualitatively explained based on conventional thermally activated gas diffusion and by carefully accounting for the participation of the silica tube to radiation transfer along with the spectral properties of the silica tube and the glass samples. In brief, the radiation emitted by the incandescent lamp is concentrated between 0.5 and 3.0 µm and reaches directly the sample since the silica tube is nearly transparent up to 3.5 µm. On the contrary, for furnace heating at 400 o C, the silica tube absorbs a large fraction of the incident radiation which reduces the heating rate and the H 2 release rate. However, between 0.8 and 3.2 µm undoped borosilicate does not absorb significantly. Coincidentally, Fe 3 O 4 doping increases the absorption coefficient and also reacts with H 2 to form ferrous ions which increase the absorption coefficient of the sample by two orders of magnitude. Thus, doped and reacted 1 samples heat up much faster when exposed to the heating lamp resulting in the observed faster response time and larger H 2 release rate.Keywords: hydrogen storage, photo-induced gas diffusion, hollow glass microspheres, outgassing NOMENCLATURE c p Specific heat at constant pressure (J/kg.K)

Clinical and radiological diagnosis of infantile fibrosarcoma (IFS) is challenging because of its similarity to vascular origin tumors. Treatment involves complete resection. Although chemotherapy may allow more conservative resection, treatment guidelines are not strictly defined. One IFS patient with an unresectable tumor had disease progression during chemotherapy. A primary tumor sample showed high VEGFR-1/2/3 and PDGFR-α/β expression. After pazopanib therapy, most tumor showed necrosis within 29 days and could be removed completely, with no relapse in 8 months post-resection. When IFS features hypervascularity, VEGFR and PDGFR expression may be high, thus allowing consideration of VEGFR inhibitors such as pazopanib.