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In this study, we examine texturing features on soda-lime (SDL) silicate glass bottles achieved using a Carbon Dioxide (CO2) laser with continuous wave power (25 W at 10.6 µm). SDL glass samples were subjected to irradiation in both static and dynamic modes. In the static mode, exposure time (τON) varied from 10 µs to 2 ms, while the dynamic mode involved scan velocities (line) ranging from 20 mm/s to 3 m/s. Our evaluation focused on engraving rate, fracture morphologies, and damaged zone characteristics. Using optical microscopy and stylus profilometry, we identified three distinct process regimes: partial texturing, full texturing, and material removal. To gain insights into the underlying mechanisms of the process, we developed a 2D axisymmetric thermo-mechanical model using COMSOL Multiphysics®. This model allowed us to compute the transient laser-induced thermal stress and the relaxation occurring in the viscoelastic state of SDL. Remarkably, our simulation demonstrated a correlation between the tensile cracking threshold of SDL (0.1 GPa) and experimental data. By comapring the experimental and simulation results, we were able to estimate the damaged zone diameter with an accuracy of ±3% in the partial texturing regime and an overall accuracy of ±8% across all regimes in the static mode. [ABSTRACT FROM AUTHOR]

Crystal glass alteration in an aqueous medium has been extensively studied following the implementation of strict regulations regarding lead leaching. However, despite the widespread use of lead glasses and crystal glass by artists and artisans ever since antiquity, few works focus on crystal glass corrosion in atmospheric conditions. In this preliminary study, the altered layers formed on crystal glass in aqueous and atmospheric conditions at 90°C are compared. On the timescale studied (20 days), ToF‐SIMS profiles of both altered layers show water ingress. This hydration step is correlated with K leaching in aqueous media, and 29Si and 27Al NMR analysis of the altered structure highlights the formation of new Q4 and AlO6 units. Low alkali leaching is observed in atmospheric conditions, but the altered glass structure is highly hydrolyzed, as attested by its high water and silanol content. As a result, the altered layer formed in aqueous conditions is more polymerized than the one formed in atmospheric conditions, and potentially more passivating through a mechanism involving water availability. On the bases of 29Si/1H and 27Al/1H CP‐MAS NMR experiments, the oxygen repartition is described in the altered glasses, differentiating the oxygen atoms involved in structural NBO from that of hydroxyl groups. [ABSTRACT FROM AUTHOR]

[super 27]Al solid-state NMR study is conducted to explain the cation sublattice disorder induced in [MgAl.sub.2][O.sub.4] and [ZnAl.sub.2][O.sub.4] spinels by the swift heavy ions.

The Zerodur® glass-ceramic chemical durability has been studied by leaching. The nuclear magnetic resonance spectroscopy analysis has allowed highlighting the network changes. A macroscopic evaluation of the surface alteration has been performed by contact angle measurements, this analysis being sensible to the roughness and the hydrophilic character. In basic solutions, depolymerization phenomena concern all former cations, as result of hydrolysis phenomena. A preferential attack of the interface matrix-nanocrystals, implicating phosphorus involves some nanocrystals removing. The Zerodur® glass-ceramic keeps an excellent chemical durability during exposition to acidic aqueous solutions. But in basic medium, the biphasic nature involves a strong alteration. [ABSTRACT FROM AUTHOR]

Chemical disorder can be characterized in silicate glasses using spectral editing in 29Si solid-state NMR. Resonances of the Qn(mX) (i.e.Si(OX)m(OSi)n−m) molecular motifs, which strongly overlap in the 29Si solid-state NMR spectra of silicate glasses, can be separated and quantified using 2 to n-quantum filters in INADEQUATE-like experiments, without prior knowledge of assigned chemical shifts, offering a new probe for the microscopic origins of residual entropy in glassy materials. [ABSTRACT FROM AUTHOR]

The structural study of lanthanum sodium aluminoborosilicate (55SiO 2 -(25-x) Al 2 O 3 -xB 2 O 3 –15Na 2 O–5La 2 O 3) glasses were investigated. The structural characterization by solid state Nuclear Magnetic Resonance have outlined the role of aluminum/boron substitution. This study has a particular interest for applications like the nuclear waste glass storage. Various types of matrices have been considered for containment: borosilicate, aluminosilicate and aluminoborosilicate, the latter with a high rare earth content ability is of particular interest. This system will be considered in our study from the point of view of a simple five-oxide glass, rich in TR 2 O 3 (TR = La), in order to provide additional elements of understanding to the model glasses of containment for nuclear waste, lanthanum simulating, among other things, all lanthanides as well as minor actinides contained in the waste. In this paper, ourwork focused on the study of the influence of boron on the structure by solid state Nuclear Magnetic Resonance (NMR). In particular, we examine the impact of aluminum/boron substitution in a series of glasses in term of structural changes. • We have investigated a composition of glasses with a high content of rare earth elements. • 29Si,27Al, 23Na and 11B MAS NMR was used to describe the vitreous aluminoborosilicate network. • Glasses homogeneity is discussed according to the influence of boron/aluminum substitution. • NMR spectroscopy gave a better discerption to discuss the structure in term of Qn(mAl) and Qn species. [ABSTRACT FROM AUTHOR]

Abstract: From a presentation of the various nuclear magnetic resonance (NMR) experiments that allows to characterize the local structure and dynamics of oxide glasses and melts, we show that it becomes possible to evidence not only the details of the coordination state of the constituting atoms but also the nature of polyatomic molecular motifs extending over several chemical bonds. [Copyright &y& Elsevier]

Scalar couplings, recoupled or full dipolar interactions can be used to characterize multinuclear structural molecular motifs in solids, by counting the neighbouring spins in solid-state NMR, opening new ways for the differentiation of overlapping spectral responses which is a limiting factor in many high resolution experiments carried out on disordered systems.

MgAl2O4 and ZnAl2O4 spinels have been irradiated by swift heavy ions (86Kr and 36S) simulating the irradiation by fission products for applications in the transmutation targets. The structures of unirradiated and irradiated spinel samples have been studied by NMR spectroscopy, with 27Al magic angle spinning and multiple-quantum magic angle spinning experiments. The parameters of fluence and electronic stopping power have been compared. For 86Kr ions, the obtained spectra are modified by irradiation: we observe a rise of the amount of aluminum in tetrahedral sites and a widening of the lines associated with the different aluminum environments compared with those of the pristine samples. Site exchange in the cationic sublattice is then observed and can be quantified from NMR spectra, determining the inversion parameter. An inversion parameter of 0.77 is estimated for the MgAl2O4 spinel irradiated with 1013 Kr ions/cm2, for a value of 0.275 in the pristine samples. Moreover, a line attributed to aluminum in 5-fold coordination with oxygen is observed in irradiated spinel samples at the maximum fluence for krypton. These new aluminum environments can characterize a transition layer which could change toward an amorphous layer, increasing the electronic stopping power and/or the fluence.