An investigation was made as to the effect of trace impurities, particularly bismuth and boron, on etching morphology and capacitance of aluminum electrolytic capacitor foil. It was found that as little as 2 wt‐ppm bismuth in foil strongly accelerated surface etching, inhibited tunneling, and consequently lowered capacitance. 3 wt‐ppm boron also enhanced surface etching, but lowered capacitance less than bismuth. The reason for these results was considered

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Barium zinc phosphate glasses formulated in the xBaO–(60 − x)ZnO–40P2O5 composition line are investigated for their optical, thermal, and chemical characteristics. These as well as small stress‐induced birefringence were found to be governed by the BaO/ZnO substitution. In addition to the characterization of the properties, the phosphate network was qualitatively and quantitatively described in terms of Q2 and Q1 ratios by 1D 31P magic angle spinning nuclear magnetic resonance spectroscopy experiments that also showed the presence of Q0 sites. It turns out that the small perturbations of their photoelastic, magnetic, and chemical characteristics made these glasses very good candidates for use in polarization‐controlling optical devices.

Mesoporous silica features open and accessible pores that can intake substances from the outside. The combination of mesoporous silica with plasmonic nanostructures represents an interesting platform for an optical sensor based on the dependence of plasmonic modes on the refractive index of the medium in which metallic nanoparticles are embedded. However, so far only a limited number of plasmonic nanostructures are combined with mesoporous silica, including random dispersion of metallic nanoparticles and flat metallic thin films. In this study, we make a mesoporous silica layer on an aluminum nanocylinder array. Such plasmonic arrangements support both localized surface plasmon resonances (LSPRs) and extended modes which are the result of the hybridization of LSPRs and photonic modes extending into the mesoporous layer. We investigate in situ optical reflectance of this system under controlled pressure of isopropanol vapor. Upon exposure, the capillary condensation in the mesopores results in a gradual spectral shift of the reflectance. Our analysis demonstrates that such shifts depend largely on the nature of the modes; that is, the extended modes show larger shifts compared to localized ones. Our materials represent a useful platform for the field of environmental sensing.

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