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Showing 1 to 20 of 63 for “"TEOS"”.
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The preparation and characterization of PEK/TEOS glasses by the sol-gel method
… precursors such as tetraethylorthosilcate (TEOS) to build an inorganic glass matrix out of solution by a two step poly(hydrolysis-condensation) reaction mechanism. The benefits of making ceramics by this method include considerable energy savings due to the lower sintering temperatures …
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An Investigation of Electrostatic Interactions Between Organically Functionalized Silica Particles, Surfaces, and Metal Ions
… the mol% of APTES in a tetraethoxyorthosilicate (TEOS) particle formulation. Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) were used to analyze the particles for size, shape, and composition. Silica particles with all three functionalizations were used for …
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Investigation of an alternative sulfonated silane in ceramic carbon electrodes for fuel cell applications
… method the use of tetraethylorthosilicate (TEOS) and a small amount of 3-(trihydroxysilyl) propane-1- sulfonic acid (TPS) as the ionomer demonstrated increased porosity, better durability, and better fuel cell performance at low RH when compared to the traditional Nafion ionomer material. In …
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Use of a quartz crystal microbalance to investigate the mechanical stability of silica xerogel membranes for volatile iodine capture
… sol-gel processing using only tetraethoxysilane (TEOS), TEOS with oil as porogen, TEOS with bismuth nanoparticles, and TEOS with both. The technique subjected the adsorbents to a gas stream and used adhesive-coated quartz crystal, connected to a quartz crystal microbalance (QCM), to collect the …
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BISMUTH-FUNCTIONALIZED SORBENTS FOR RADIOIODINE CAPTURE
… of gels made with tetraethoxysilane (TEOS) and TEOS + methyltrimethoxysilane (MTMS) silica precursor. Oil concentrations of 9.09 v/v% and 33.33 v/v% were studied. The miscibility of the oil and precursor decreased as the silica gel network formed, leading to oil-rich regions within the …
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Gas-phase synthesis of gold- and silica-coated nanoparticles.
… silica coatings from tetraethyl orthosilicate (TEOS) on the surface of nanoparticles (diameter ~5-70 nm). Tandem differential mobility analysis (TDMA) of the process demonstrates that particle coatings can be produced with controllable thicknesses (~1-10 nm) by varying system parameters such as …
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The design, synthesis and characterization of chitosan-based interpenetrating polymer networks and thin film systems
… chitosan with a tetra ethyl orthosilicate (TEOS) cross-linker to form an interpenetrating polymer network (IPN). In combination with a variety of ordered and disordered polymer and metal nanoparticles, the composites formed were studied with respect to their optical, mechanical and …
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Physical and Gas Permeation Properties of a Series of Novel Hybrid Inorganic-Organic Composites Based on a Synthesized Fluorinated Polyimide
… fluorinated polyimide and tetraethoxysilane (TEOS), tetramethoxysilane, methyltrimethoxysilane (MTMOS), and phenyltrimethoxy-silane (PTMOS) employing the sol-gel process. Polyimides were synthesized from 4,4'-hexafluoroisopropylidene dianiline (6FpDA) and …
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''Auta minua saamaan lapsia, tai muuten minä kuolen!'' – Intertekstuaalinen analyysi Margaret Atwoodin Orjattaresi-dystopian Raamatun käytöstä naisten kontrolloimisen oikeuttamiseksi.
… on ymmärtää lainauksen merkitys teoksessa. Teos kertoo Offred nimisestä orjattaresta, joka elää teokraattisessa Gileadin yhteiskunnassa, joka on alhaisen syntyvyyden vuoksi palautettu Raamatun aikaiseen, patriarkaaliseen järjestykseen. Offred on orjattarena pakotettu synnyttämään lapsia …
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Structure/property behavior of inorganic/organic sol-gel derived hybrid materials
… to form a network from tetraethylorthosilicate (TEOS) and triethoxysilane end capped oligomers of poly( tetramethylene oxide) (PTMO). The structure-property relationships were determined for these hybrid networks from their dynamic mechanical behavior, mechanical properties, and SAXS behavior. …
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Characterizaton of Triethoxyfluorosilane and Tetraethoxysilane Based Aerogels
… (TEFS) and tetraethoxysilane (TEOS) were used to prepare bulk aerogels. Samples were prepared by sol-gel methods, and then carbon dioxide supercritically-dried. Effects of varying the water to precursor ratio were studied with respect to aerogel properties and microstructure. …
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Studies of the Preparations and Use of Sol-Gel for Enzyme Immobilization and Analytical Applications.
… electrochemically with tetraethyl orthosilicate (TEOS) as precursor. The sol-gel made with TEOS as precursor and HCl as catalyst showed stability in enzyme activity for 11 uses but the activity decreases on the same sol-gel when modified with silica nanoparticles. Factors such as optimal …
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Inorganic-organic hybrid materials and abrasion resistant coatings based on a sol-gel approach
… silyl groups and, tetraethylorthosilicate (TEOS) under basic conditions met with only partial success. The films obtained had low mechanical stability. This was attributed to the low reactivity of the triethoxy species under neutral and basic conditions. In contrast, films with good …
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Síntese de novas matrizes de sílica contendo grupos éteres coroa
… de sílica o precursor tetraetilortosilicato (TEOS). Os materiais foram sintetizados pelo método tradicional e por rotas alternativas como forno mufla e microndas. Os materiais foram caracterizados por um conjunto de técnicas como análise elementar, ressonância magnética nuclear de 13C e 29Si, …
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MATERIALS CHARACTERIZATION FOR SUB-MICRON SUPERCONDUCTING INTERCONNECTS IN RECIPROCAL QUANTUM LOGIC CIRCUITS
… Nb wires embedded in Tetraethyl orthosilicate (TEOS) dielectric. The Nb and TEOS losses as a function of microstrip width down to 0.25 $\mu m$ are modeled and measured. The electrical and physical material properties for 3 RQL processes over 5 wafers are evaluated.The electrical properties were …
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The chemical vapour deposition of Tetraethoxysilane on Zeolite ZSM-5
… and the same sample employing tetraethoxysilane (TEOS) as silica precursor at deposition temperatures ranging from 50 to 400°C. After each CVD treatment the catalyst is tested with appropriate test reactions in order to quantify the extent of modification. The gradual inertisation of the external …
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The inertisation of the zeolites ZSM-5, mordenite and beta by chemical vapour deposition using tetraethoxysilane
… Chemical vapour deposition - Tetraethoxysilane (TEOS) was contacted with the catalyst using a vapour phase flow system and static vacuum system. The effects of deposition temperature and time were varied in order to vary the amount of TEOS deposited on the samples. The effect of the decomposition …
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Process-Induced Degradation during the Integration of Pb(Zr/x Ti/1-x)O3 Ferroelectric Capacitors
… (ILD) materials, ECR CVD Oxide and PECVD TEOS Oxide (PE-TEOS). Since the stress of PZT capacitor strongly depends on the ILD deposition temperature, the PZT capacitor with PE-TEOS showed more compressive stress than that with ECR oxide, which results in severe remnant polarization (Pr) …
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Siloxane modified hybrid materials by the sol-gel process
… inorganic component tetra-ethyl orthosilicate (TEOS), instead of TIP was also studied. The TEOS/pDMS materials showed more phase mixing than the TIPIPDMS materials, although, the dielectric tan δ peak maxima appeared at a lower temperature. The TEOS/PDMS materials were also less stiff than the …
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