Mesoporous silica metal oxide (ZnO and CdO) thin films have been used as metal ion precursors to produce the first examples of mesoporous silica metal sulfide (meso-SiO(2) @ZnS, meso-SiO(2) @CdS) or silica metal selenide (meso-SiO(2) @ZnSe, meso-SiO(2) @CdSe) thin films, in which the pore walls are made up of silica and metal sulfide or metal selenide nanoflakes, respectively. A gentle chemical...

We describe an observing campaign using the Very Long Baseline Array (VLBA) to monitor the time-evolution of the v = 1, J = 1−0 SiO maser emission towards the Mira variable TX Cam. The data reported here cover the period 1997 May 24 to 1999 February 19, during which the SiO maser emission was im-aged at approximately biweekly intervals. The result is an animated movie at an angular resolution o...

Femtomolar concentrations of hydrogen fluoride, a decomposition component of nerve agents, were detected using a SiO(2) microcantilever. The microcantilever underwent bending due to the reaction of HF with SiO(2). The microcantilever deflection increased as the concentration of HF increased. Other acids, such as HCl, had no effect on the deflection of the cantilever. The mechanism of reaction-i...

BiOCl-SiO₂ KIT-6 composite materials with raspberry-like structures are facilely prepared under hydrothermal conditions. The mesoporous siliceous support of SiO₂ KIT-6-incorporated BiOCl with enlarged yet refined surface morphology characterized by physiochemical methods exhibits an improved electrochemical performance. A sensitive electrochemical detection method of cadmium concentration using...

Although version spaces provide a useful conceptual tool for inductive concept learning, they often face severe computational difficulties when impls mented. For example, the G set of traditional boundary-set implementations of version spaces can have size exponential in the amount of data for even the most simple conjunctive description languages [Haussler, 19881. This paper presents a new rep...

We demonstrate a surface enhanced Raman scattering (SERS) substrate by integrating plasmonic-active SiO(2) nanotubes into Si(3)N(4) gratings. First, the dielectric grating that is working under guided mode resonance (GMR) provides enhanced electric field for localized surface plasmon polaritons on the surface of metallic nanoparticles. Second, we use SiO(2) nanotubes with densely assembled silv...

Oxidation of SiC produces SiO(2) while CO is released. A "reoxidation" step at lower temperatures is, however, necessary to produce high-quality SiO(2). This step is believed to cleanse the oxide of residual C without further oxidation of the SiC substrate. We report first-principles calculations that describe the nucleation and growth of O-deficient C clusters in SiO(2) under oxidation conditi...

This chapter focuses on one of the most studied aerogel materials, silica aerogels. It aims at presenting a brief overview of the elaboration steps (sol–gel synthesis, aging, and drying), the textural and chemical characteristics (aggregation features, porosity, and surface chemistry), the main physical properties (from thermal, mechanical, acoustical, and optical, to biological, medical, etc.)...

We report a new nanomaterial in which ciprofloxacin molecules are incorporated inside silica nanobubbles, denoted as ciprofloxacin@SiO2. The material has been characterised using UV/Vis absorption spectroscopy, transmission electron microscopy, cyclic voltammetry, and emission spectroscopy. The material is stable and the freestanding particles can be precipitated and redispersed in several solv...