Boron-silicate glass

As a second example, results from a TOP ERDA measurement for a multi-element sample are shown in Fig. 3.65 [3.171]. The sample consists of different metal-metal oxide layers on a boron silicate glass. The projectiles are 120-MeV Kr ions. It can be seen that many different recoil ions can be separated from the most intense line, produced by the scattered projectiles. Figure 3.66 shows the energy spectra for O and Al recoils calculated from the measured TOF spectra, together with simulated spectra using the SIMNRA code. The concentration and thickness of the O and Al layers are obtained from the simulations. 

Note The remainder of the composit consisted of 80 wt% filler consisting of barium- aluminum-boron silicate glass powder, silicon dioxide-zirconium dioxide, and ytterbium fluoride. For dental composites lower viscosities are preferred because of their flowability. 

FORMATION OF THE PbS QUANTUM DOTS IN BORON-SILICATE GLASS MATRIX... 

PbS nanoparticles with features of quantum dots (QDs) have been fabricated in boron-silicate glass matrix. Their mean diameter was found to be in the range of 3.4-8.2 nm from the optical spectroscopy data due to their explicit quantum confinement effect. The particle size and position of the absorption bands can be controlled through the regimes of thermal treatment of the glasses. SAXS technique showed near to monodispetse size-distribution of QDs and possible ordering within the glass matrix. 

The fabrication of PbS QDs in the boron-silicate glass matrix has been elaborated. Particle size, and correspondingly, optical absorption was shown to be controlled through the different combinations of the heat treatment. The presence of the heterogeneity areas within the glass structure has been detected with SAXS. The features in size distribution and ordering of particles have been suggested on the basis of SAXS data. 

Formation of the PbS quantum dots in boron-silicate glass matrix. 136... 

E-glass, an alkali-poor calcium-aluminum-boron-silicate-glass, for polymer reinforcement and for applications in the electrical sector... 

C-glass, an alkali-calcium-boron-silicate-glass, with particularly high chemical resistance... 

Porous glasses were first prepared and described by Grebenshchikov and co-workers (State Optical Institute, Leningrad) (89, 90). This research was continued by Zhdanov and co-workers (85-87). Usually, porous glasses are prepared by treating sodium-boron silicate glasses with inorganic acids. 

Abbreviation denotes type of matrix (S - silicate glass, B - boron silicate glass, P - phosphate glass, C - colloid solution) and QDs size in angstroms. 

After their discovery, the d Elhuyar brothers wrote that no use has yet been found for the new metal but we must not conclude from this that it is entirely useless . This was an under-statement The physical properties of the metal have made it very useful in a modern society. The melting point is the highest of all elements, 3422°C. Above 1650°C it also has the highest tensile strength of all metals. Its electrical and thermal conductivity are good, 30% and 40% respectively of the values for copper. The metal can easily be melted into glass as it has the same low coefficient of thermal expansion as boron silicate glass. The metal has also a very low specific heat, which, in... 

Orthopedic devices, 3 721-735 joint replacement, 3 727-735 Orthopedic marrow needles, 3 743-744 Orthophosphate (PO4), in soil, 11 112 Orthophosphates, 18 830-841 20 637 magnesium, 18 839 manufacture of, 18 853-855 Orthophosphate salts, 18 836 Orthophosphoric acid, 18 815, 817-826 condensation of, 18 826 properties of, 18 817-819 solubility of boron halides in, 4 140t orf/zo-phthalic resins, 20 101, 113 formulation of, 20 102 Orthorhombic crystal system, 8 114t Orthorhombic phosphorus pentoxide, 19 49 Orthorhombic structure, of ferroelectric crystals, 11 95, 96 Orthorhombic symmetry, 8 114t Orthosilicate monomers, in silicate glasses, 22 453... 

Place 0.1000 g of sample into a 30-ml plastic jar having a screw cap. Add 5 ml of cold water and tiien 5 ml of cold 29 M HF. Cap tightly and set aside at room temperature until dissolution is complete (1—24 h). Nearly all silicate glass samples do not require heat for dissolution, but if heat is applied then a viable seal must be assured in order to prevent Ihe loss of boron as the fluoride. (Insoluble fluorides and unreactive oxides may remain... 

Figure 5.1-10 IR absorption spectrum of a boron-phosphorous-silicate glass coated wafer for the determination of the boron and phosphorous content of the Si02 coating (sample thickness less than 1 pm, resolution 4 cm ).

Several contending technologies are presently being used to achieve local and global planarizations that include spin on deposition (SOD), reflow of boron phosphorous silicate glass (BPSG), spin etch planarization (SEP), reactive ion etching and etch back (RIE EB), spin on deposition and etch back... 

In the present paper, we consider the glasses derived on the basis of boron-silicate matrix doped with PbS and demonstrate the pronounced absorption... 

Sand, preferably fine particulate, is used as the source of Si02 in the manufacture of silicate glasses. Raw materials for the standard network-modifiers are lime, dolomite (CaC03 MgC03) for the alkaline earth oxides, sodium carbonate for sodium oxide, feldspar (sodium potassium calcium aluminum silicate), or other naturally occurring aluminum silicates, for aluminum oxide. Boron is used in the form of boric acid, borax and other boron minerals, e.g. ulexite (NaCa[B505(0H)6] 5H2O) or colemanite... 

Dandk and LiCko (1981) verified their apparatus in a very broad temperature range, from room temperature up to 1600°C. They measured the density and viscosity of glycerine, boron oxide, sodium tetraborate, and sodium-calcium silicate glass with the composition 17 mass % Na20, 10% CaO, 73% Si02. The results of measurement are in agreement with the literature data regarding the precision of the apparatus used. 

The necessary incorporation of dopants (e.g., phosphorus and boron doped in silicate glasses) usually lowers deposition rates, due to competitive surface binding. 

Taking into account that the luminescence decay of PbS QDs placed in the boron silicate and the phosphate glasses is not monoexponential one can conclude that the dots in these matrices are trapped at various defect states. The origin of the variation of defect types may be due to short time of dots growth in these matrices (tens of minutes - to several hours) in comparison with the silicate glass (several tens of hours). In silicate glasses and in colloids variation of defect types in which excited charge carriers are trapped is presumably narrower. The luminescence decay of PbS QDs in them is close to the monoexponential law. 

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