The electric conductivity of the quartz-like glass containing cesium cations

The results of the measurement of the electric conductivity of the quartz-like glass obtained on the basis of the porous high-silica alkali borosilicate (ABS) glass are presented. Porous glass has been impregnated with aqueous solutions containing cesium ions and then subjected to thermal treatment to the pore collapse. The values of the activation energy for the electric conductivity of the obtained quartz-like glass have been calculated.     

Uptake of cesium and strontium cations by potassium-depleted phlogopite

Phlogopite mica was equilibrated with 1.0 N sodium chloride (NaCl)–0.2 N sodium tetraphenylborate (NaTPB)–0.01 M disodium ethylenediaminetetraacetic acid (EDTA) solution at room temperature resulting in an almost complete removal (92%) of the mica's interlayer K. X-ray powder diffraction analysis provides additional evidence that hydrated Na⁺ ions had almost completely replaced the interlayer K⁺. Following equilibration, the c-axis spacing of the mica increased from 10.0 Å to approximately 12.2 Å. Cesium and Sr ion exchange isotherms indicate that K-depleted phlogopite is highly selective for both elements, the Cs⁺ exchange capacity is 1.26 meq/g or 65% of the theoretical cation exchange capacity and the Sr²⁺ exchange capacity is 1.94 meq/g or 100% of the theoretical exchange capacity of the mica. Kielland plots indicated that the mica was selective for Cs⁺ when the equivalent exchange capacity of Cs⁺ in the exchanger phase (X¯_Cs) was < 0.66 and selective for Sr²⁺ when X¯_Sr < 0.41. At equivalent fractions greater than these levels, layer collapse and/or steric effects limit the diffusion of these ions into the interlayers of the mica. Analysis of the Cs⁺ equilibrated mica utilizing XRD indicated that a collapse of the c-axis spacing had occurred. Based on the high selectivity of < 45-μm K-depleted phlogopite for Sr²⁺ and Cs⁺, this material may prove useful as an inorganic ion exchanger for these radioactive isotopes.     

Viscosity of polystyrene near the glass transition

A quantitative explanation is given for the apparent viscosity increase with increasing capillary shear rate for polystyrene at temperatures approaching the glass transition, T_g. Possible shifts in T_g as a function of the parameters shear rate, frequency, and pressure are interrelated to viscosity changes. Experimentally, the Instron capillary rheometer and the Weissenberg rheogoniometer provided a means for uncoupling the variables for individual consideration. Calculated and experimental data for the apparent viscosity as a function of the given parameters are presented and discussed. The explanation of the apparent viscosity increase in capillary flow can be quantitatively explained through the pressure dependence of T_g. Brief mention is made of the pressure effects on the Bagley and Rabinowitsch corrections normally made in capillary measurements.     

Viscosity of copolymers containing carbon black

The flow behavior of random copolymers of styrene and butyl methacrylate containing specific carbon blacks varying in surface area were studied at various temperatures and shear rates. Master curves of reduced viscosity as a function of shear rate were prepared for the pure copolymers at 150°C. The superposition required vertical and horizontal shifts, proportional to (a_T)^?1 and (a_T)^.53, respectively, where a_T is the shift factor. With the incorporation of carbon black, the viscous response is non-Newtonian exhibiting a yield stress at increasing filler concentration and surface area. Master curves of viscosity against shear rate were generated at fixed filler loadings and surface areas by using a single horizontal shift factor.     

Determination of the cesium content in ShChVT electrode glass

Translated from Steklo i Keramika, No. 4, p. 30, April, 1991.     

Viscosity and die swell of acrylonitrile-butadiene-styrene filled with glass beads and glass fibers

Shear viscosity and die swell ratio of acrylonitrile-butadiene-styrene filled with glass beads and glass fibers were measured. The relative viscosity of the composites increased with filler content, but decreased with shear rate. At low shear rates, fiber filled systems had higher relative viscosities than bead filled systems. At high shear rates, the opposite was observed. The die swell ratio of the unfilled material increased linearly with the logarithm of the shear rate. Systems highly filled with glass beads or fibers showed a maximum in the die swell ratio at medium shear rates. The magnitude of the maximum in the die swell ratio increased with the filler content and the die length, up to a certain length, in a series of dies that had the same radius. The presence of a maximum in the die swell ratio of the filled melts is explained by an order-disorder phenomenon observed earlier by Wu.     

Chalcogenide glass containing lead halides

The glass of the As₂S₃-Sb₂S₃-PbΓ₂ system, where Γ = Cl, Br, and I, has been synthesized by welding in vacuum-treated quartz ampoules. The glass has been obtained by slow cooling in furnace. The effect of the type of halogen on vitrification has been shown; and the glass-transition temperatures have been determined.     

Properties of concrete containing waste glass

In our study, in which waste glass (WG) is considered as coarse aggregates in the concrete, WG was used reduced to 4-16 mm in proportions of 0-60% in the production of PKÇ/B 32.5/R type cement. The effects of WG on workability and strength of the concrete with fresh and hardened concrete tests were analyzed. As a result of the study conducted, WG was determined not to have a significant effect upon the workability of the concrete and only slightly in the reduction of its strength. Waste glass cannot be used as aggregate without taking into account its ASR properties. As for cost analysis, it was determined to lower the cost of concrete productions. Our study was an environmental one in consideration to the fact that WG could be used in the concrete as coarse aggregates without the need for a high cost or rigorous energy.     

Sheet glass containing added phosphorus pentoxide

Translated from Steklo i Keramika, No. 5, pp. 7–9, May, 1990.     

Development of glass ceramic coatings containing hydroxyapatite

Glass ceramic composites — to be used for coatings on titanium implants — based on leucite glass with elevated flux content and added hydroxyapatite or a mixture of hydroxyapatite and fluorite are examined. It is established that pastes containing no more than 30% hydroxyapatite in leucite glass are the best materials for denture coatings. Pastes with a higher content of hydroxyapatite Ca₁₀(PO₄)₆(OH)₂(> 30%) are recommended for coatings on intramaxillary titanium implants. __________ Translated from Steklo i Keramika, No. 4, pp. 34–36, April, 2007.     

Viscosity properties of cellulose solutions in dimethylacetamide containing lithium chloride

Conclusions The effect of solvent composition and temperature on the properties of dilute and concentrated solutions of cellulose in dimethylacetamide containing lithium chloride has been examined.Increasing the lithium chloride content of the solution leads to the appearance of an inflection on the reduced viscosity-concentration dependence in the region of low cellulose concentrations (0.3 g/dl), which disappears on the addition of 1% water (by wt.) to the solution.Translated from Khimicheskie Volokna, No. 4, pp. 26–28, July–August, 1986.