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Showing 1 to 20 of 20 for “"Chemical Durability"”.
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The Chemical Durability of Elastomeric Bituminous Geomembranes (BGMS) in Different Geoenvironmental Applications at Elevated Temperatures
The chemical durability of elastomeric bituminous geomembranes (BGMs) is investigated using laboratory accelerated immersion tests for different geoenvironmental applications. The effects of elevated temperatures, thickness, and incubation media on the mechanical, rheological, and chemical …
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Modeling of Radiation Effects on the Chemical Durability of Nuclear Waste Forms (Leaching, Radioactive Glass Damage)
… waste, the long-term effects of radiation on chemical durability are attributed to the accumulation of atomic displacements; the latter are caused mainly by the recoiling nuclei, or (alpha)-recoils, accompanying the emission of (alpha)-particles resulting from the presence of actinides in the …
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Immobilization of radioactive materials in iron phosphate glass
… iron phosphate glass at ≤ 1200°C in 1 hour. The chemical durability of iron phosphate glassy wasteforms was as good as, or better than a reference borosilicate glass (10<sup>-9</sup> g/cm<sup>2</sup>/min) in distilled water at 90°C. Adding 7 wt% CaF₂ to the batch decreased the melt temperature by …
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Immobilization of actinide wastes in ceramics for long-term disposal
… due to its high solubility of actinides, high chemical durability and exceptionally high stability under irradiation over a vast temperature range. Cubic materials swell isotropically when damaged by radiation under different strains. This leads to less microcracking in a repository. They are …
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High thermal expansion phosphorus oxide and oxynitride glasses
<p>"The chemical durability of phosphate glasses in general can be improved by the incorporation of chemically dissolved nitrogen and/or addition of oxides such AI<sub>2</sub>O<sub>3</sub>.</p> <p>Over 100 oxide and oxynitride glass compositions were evaluated. The general compositions investigated …
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Structure and properties of iron phosphate glasses: A novel host matrix for the vitrification of high-level nuclear wastes
… and crystallization characteristics, and the chemical durability of vitreous binary iron phosphates of approximate batch composition 40Fe<sub>2</sub>O<sub>3</sub>-60P<sub>2</sub>O<sub>5</sub> (mol%) and those containing up to 40 wt% of one or more common nuclear waste components such as …
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Phosphate-doped borosilicate enamel coating used to protect reinforcing steel from corrosion
… like T<sub>g</sub>, T<sub>s</sub> and CTE, and chemical durability in alkaline environments can be improved, particularly for glasses co-doped with alumina. When the solubility limit is reached, a phase-separated microstructure forms, degrading the chemical durability of the glass because of the …
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Dynamic Light Scattering in Alkali Borate Glass Melts Near the Glass Transition
… due to their low melting temperature, high chemical durability, and potential for optical and electronic applications. However, the properties of borate glasses are strongly influenced by their dynamics, which are difficult to study using conventional techniques. Photon correlation …
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Synthesis and characterization of purely sulphonated and composite membranes for high temperature fuel cells
… used today is Nafion. Nafion is ideal due to its chemical durability and high proton conductivity however it is highly expensive and limited to 80˚C during operation. To target these issues two methods have been developed. One was to synthesize a new membrane material to replace Nafion based upon …
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Chemical corrosion of Ag films on glass
<p>"The chemical corrosion of chemically, vacuum and sputter deposited Ag films on an aluminoborosilicate and a soda lime glass was investigated in wet HCl and saturated water vapor as a function of concentration, temperature and time. The higher corrosion resistance of chemically deposited Ag …
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Chemical performance of cement stabilised contaminated clay
… concerns over long-term effectiveness and durability of S/S needs to addressed, because contamination is contained but not removed. This requires effective chemical assessments to inform design. This study aims to design a suitable method for assessing S/S effectiveness, using a holistic …
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Developing an understanding of the relationship between the durability of simplified and complex UK radioactive waste glasses
… has meant the effects of Li on the aqueous durability of UK waste glasses needed to be investigated. Additionally, dissolution experiments commonly take place at a higher temperature than the expected temperature of groundwater within a geological disposal facility. As such, the effects of …
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Bragg Coherent Diffraction Imaging of Metal Microcrystals Using a Multipurpose In Situ Cell Design
… processes. Combined with an experimental electrochemical cell, BCDI is a promising tool for providing insight into the problems facing advanced materials in next-generation reactor designs. In this work, a custom designed electrochemical cell, successfully adapted for use at four beamlines, was …
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Development and characterisation of calcium phosphate glasses and glass-ceramics containing fluorine and titanium
… known to be one of the ways in order to improve chemical durability of calcium phosphate glass-ceramics. [41-42] In the present study, type A glass and glass-ceramics demonstrated the effect of TiO2 addition with reduction of calcium to phosphorus ratio and type B glass and glass-ceramics …
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Processing parameters and kinetics of phosphate-based dechlorination for electrorefiner salt waste
… materials due to the high waste loading, good chemical durability, and lower processing temperatures. Phosphate-based dechlorination has been used to produce intermediate phosphate products before the addition of iron to create the chemically durable final waste form. Using this method, mixing …
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Thulium-doped fibre laser in the 2 μm wavelength region for gas sensing
… to other non-oxide glass hosts in terms of their chemical durability, stability and crucial structural compatibility with readily available telecommunication optical fibres. Ideal host composition for Thulium and efficient pumping scheme posses major challenges restricting the production of …
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Innovative composite enamel coatings with improved abrasion resistance and mechanical properties
… with superior technical properties, including durability, thermal resistance, and chemical resistance. Nowadays, vitreous enamels, which are silica- based inorganic coatings deposited by high temperature (580-890 °C) vitrification, are usually employed for the protection of metallic components …