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Showing 1 to 20 of 95 for “"aluminosilicate"”.
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Novel, inorganic composites using porous, alkali-activated, aluminosilicate binders
Geopolymers are an inorganic polymeric material composed of alumina, silica, and alkali metal oxides. Geopolymers are chemical and fire resistant, can be used as refractory adhesives, and are processed at or near ambient temperature. These properties make geopolymer an attractive choice as a matrix …
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(Na,K) Aluminosilicate Hollandites: Structures, Crystal Chemistry, and High-pressure Behaviour
Aluminosilicates with the composition (Na,K)AlSi3O8 and the dense hollandite-type structure, in which all Si and Al are in six-fold coordination, are considered as a possible repository of potassium and sodium in the Earth´s mantle. The aim of this research is to explore the phase relation of the …
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Anti wetting additives for aluminosilicate refractories in molten aluminum contact applications
<p>"Aluminosilicate based refractories are widely used in furnace installations for melting aluminum because they are inexpensive, readily available and generally exhibit the properties desired from a refractory material. However, they face severe corrosion and degradation issues due to the …
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Intensive parameters of a sulfide and aluminosilicate-bearing granite, Hancock County, Maine
In Hancock County, Maine, a small mineralized fine-grained granite lies at the southeast portion of the felsic Lucerne pluton, near the contact with the Blue Hill pluton. The Cambro-Ordovician, chlorite-rich Ellsworth schist occurs to the north and south of the younger fine-grained granite and is …
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Adsorption and conformation change of short helical peptides on silica and aluminosilicate surfaces
Motivated by the challenges in understanding important features of protein adsorption, the interactions between (-helical peptides and a carefully selected set of model surfaces were studied. The peptide sequences contained three blocks of two to five residues each, with the side chains of the …
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Sodium sulfate corrosion of silicon carbide fiber-reinforced lithium aluminosilicate glass-ceramic matrix composites
… hot corrosion of a SiC fiber-reinforced lithium aluminosilicate (LAS) glass-ceramic matrix composite was studied using Scanning Electron Microscope (SEM) and X-ray Diffraction (XRD). Changes in the microstructural chemical composition of the specimens were investigated. The samples provided by …
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Hydrolysis and aqueous corrosion of silicate and aluminosilicate glasses via ab initio molecular dynamics simulation
… single and mixed alkali ions doped silicate and aluminosilicate bulk glasses are simulated using ab initio molecular dynamics (AIMD). The atomic origin of the hydrolysis reaction is analyzed, and its effects on the structural, electronic, mechanical, and optical properties of the studied glasses …
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Fabrication of metal-oxide modified porous ceramic granules from aluminosilicate clay soils for defluoridation of groundwater
… of 1.5 mg/L. This study aimed at activating aluminosilicate clay soil mechanochemically, modifying aluminosilicate clay soil with Al-oxide and fabricating porous ceramic granules using Al-oxide modified mechanochemically activated aluminosilicate clay soil/ mechanochemically activated clay …
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Magmatism, Deformation And Mesothermal Metasomatism: Interpretation Of Aluminosilicate Mineral Assemblages In The Cargo Muchacho Mountains, Southeastern California
Aluminosilicate mineral assemblages, with more than 30% Al{dollar}sb2{dollar}O{dollar}sb3{dollar} and less than 2% CaO+Na{dollar}sb2{dollar}O+K{dollar}sb2{dollar}O, occur on the western flank of the Cargo Muchacho Mountains, southeastern California. The aluminosilicate mineral assemblages are …
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Hydrothermal Reaction of Crystalline Albite, Sodium Aluminosilicate Glass, and a Rhyolitic-Composition Glass With Aqueous Solutions: A Solid State Study
… that both cation exchange and disruption of the aluminosilicate framework occur only near the mineral/solution interface and the hydrated surface layer, if it exists, is not more than about 30 angstroms thick. The rate of this reaction decreases with increasing solution pH, supporting the idea …
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Inferences on the Structure of Aluminosilicate Glasses: A High Resolution Solid-State Silicon-29 and Aluminum-27 Nuclear Magnetic Resonance Study (magic-Angle)
Framework-stoichiometry glasses and glasses in the system anorthite-diopside-forsterite were examined by high resolution solid-state silicon-29 and aluminum-27 nuclear magnetic resonance (NMR) spectroscopy. High resolution spectra were obtained at high magnetic field strengths (11.7 and 8.45 Tesla) …
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Development of Low Expansion Glaze Coatings on As Fired Si₃N₄ to Enhance Room Temperature Flexural Strength
… Si₃N₄, low expansion glaze coatings of lithium aluminosilicate (LAS) and magnesium aluminosilicate (MAS) compositions were developed. Homogeneous and crack-free glaze coatings were successfully formed on as processed Si₃N₄. This ensured formation of compressive surface stresses on the as fired …
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Alkali attack on ceramic filters
… included exposure of 42% and 60% alumina, aluminosilicates to potassium and sodium containing environments for the purpose of determining the phases that would form and to determine concentration profiles. In addition, thermodynamic calculations were performed to predict the phases that …
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High pressure diffraction studies of gallosilicate natrolite: applications to pressure-induced cation trapping
… natrolite, a synthetic analogue of the aluminosilicate mineral, was investigated in this thesis. Two forms exist, orthorhombic (as per the mineral) and tetragonal. These two forms have been synthesised and structurally characterised by powder neutron diffraction and synchrotron X-ray …
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Long-term thermal/chemical degradation of ceramic candle filter materials
… filters studied include a clay-bonded, granular aluminosilicate candle and three types of clay-bonded, granular SiC candles. The alkali, steam, and steam-alkali corrosion of these commercial ceramic candle filters was examined at temperatures ranging from 450 to 1225°C and pressures up to 1000 …
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Understanding the role of calcium on the reaction mechanism of geopolymer cements through addition of nucleation seeds
… predicted that calcium silicate hydrate/calcium aluminosilicate hydrate gel (C-S-H/C-A-S-H, a main binding phase of fly ash modified Portland cements binder) and aluminosilicate gel ((Na,K)-A-S-H, a main binding phase in geopolymer binders) co-exist in these systems. The precipitation of …
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Effects of Lignite Fly Ash on the Degradative Pathways of Aqueous Amine Solvents
… alkanolamine present. The fly ash is composed of aluminosilicate with metals interspersed throughout. The influence of the presence of fly ash in model solutions was investigated. It was found increase the degradation rate significantly, and products unique to this study were identified. The fly …
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A study of the mean-square displacement amplitudes of T and O atoms in framework silicates and aluminosilicates: evidence for rigid TO bonds, order, disorder, twinning and stacking faults in crystals
… O atoms in framework silica polymorphs and aluminosilicate structures. Criteria are established which indicate order, structural disorder or substitutional disorder in a framework crystal.
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An investigation into the active sites in co-reactants for carbonless copying paper
… ion exchanged clays and the effectiveness of aluminosilicate materials in catalysing inorganic ligand substitution reactions. Activated aluminas are shown to outperform acid activated clays as developers for CVL, with the effectiveness increasing with activation temperature up to 500°C. In …
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The catalytic reduction of nitric oxide over copper doped aluminosilicates
… to the study of catalytic NOx reduction over aluminosilicates. A copper ion-exchanged zeolite (Cu-ZSM-5) and copper oxide were studied as catalysts for the Selective Catalytic Reduction (SCR) of nitric oxide in the temperature range 250-530⁰ C. Ammonia was employed as the reducing agent. The …
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