Relevant bibliographies by topics / Silica monolith

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Academic literature on the topic 'Silica monolith'

Author: Grafiati
Published: 23 June 2022
Last updated: 14 March 2023

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Journal articles on the topic "Silica monolith"

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Alzahrani, Eman. "Green Silver Nanoparticles Confined in Monolithic Silica Disk-packed Spin Column for Human Serum Albumin Preconcentration." Current Analytical Chemistry 15, no. 6 (October 3, 2019): 616–27. http://dx.doi.org/10.2174/2210676609666181204151244.

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Background: In recent times many new uses have been found for nanomaterials that have undergone homogenous immobilization within porous supports. For this paper, immobilization of SNPs on a thiol-functionalized silica monolith using a fast, easy, environmentally friendly and costeffective process was performed. This was achieved by modifying the surface of a silica-based monolith using thiol groups, and then we fabricated green SNPs in situ, reducing an inorganic precursor silver nitrate solution (AgNO3) by employing tangerine peel extract as a reducing reagent, with Ag-thiol bonds forming along the monument. Doing this allows monoliths to be prepared in such a way that, as TEM analysis demonstrated, SNPs are evenly distributed along the rod's length. Once the materials had been fabricated, they were employed as a sorbent by being placed in a centrifuge. The SNP-thiol functionalized silica monolith was then tested using a standard protein (HSA). Methods: The process involves creating monolithic materials by employing a two-part sol-gel technique before modifying the surface of the silica-based monolith using thiol groups for hosting purposes. Homogenous surface coverage was achieved through the use of a non-toxic "green" reducing reagent (tangerine peel extract) to reduce a silver nitrate solution in place to create SNPs joined to the pore surface of a thiol-functionalized silica monolith, employing bonds of Ag-thiol. Once these materials were synthesized, they were classified by utilizing a number of methods based on SEM coupled with EDAX, TEM, AFM and BET analysis. The silica-based monolith, embedded with constructed SNPs, was employed as a sorbent in the preconcentration of human serum albumin (HSA). Results: The performance of the fabricated materials was measured against a silica-based monolith with no SNPs. Also, a silica monolith with constructed SNPs embedded was employed to capture HSA within a sample of human urine mixed with a double detergent concentrate (SDS). Such a monolith containing functionalized SNPs can be a highly effective sorbent for preconcentration of proteins in complex samples. Conclusion: It was shown to have superior performance compared to a bare silica-based monolith. Additionally, it was shown that a monolithic column modified by SNPs could preconcentrate spiked HSA in urine samples.
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Prabhakaran, D., C. Subashini, and M. Akhila Maheswari. "Synthesis of Mesoporous Silica Monoliths — A Novel Approach Towards Fabrication of Solid-State Optical Sensors for Environmental Applications." International Journal of Nanoscience 15, no. 05n06 (October 2016): 1660014. http://dx.doi.org/10.1142/s0219581x16600140.

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Mesoporous silica monoliths are an attractive area of research owing to their high specific surface area, uniform channels and mesoporous size (2–30[Formula: see text]nm). This paper deals with the direct templating synthesis of a mesoporous worm-like silica monolithic material using F127 — a triblock copolymer, by micro-emulsion technique using trimethyl benzene (TMB), as the solvent. The synthesized silica monolith is characterized using SEM-EDAX, XRD, BET, NMR and FT-IR. The monolith shows an ordered worm-like mesoporous structure with tuneable through pores, an excellent host for the anchoring of chromo-ionophores for the naked-eye metal ion-sensing. The mesoporous monoliths were loaded with 4-dodecyl-6-(2-pyridylazo)-phenol (DPAP) ligand through direct immobilization, thereby acting as solid-state naked-eye colorimetric ion-sensors for the sensing toxic Pb[Formula: see text] ions at parts-per-billion (ppb) level in various industrial and environmental systems. The influence of various experimental parameters such as solution pH, limiting ligand loading concentration, amount of monolith material, matrix tolerance level, limit of detection and quantification has been studied and optimized.
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He, Ping, Stephen J. Haswell, Paul D. I. Fletcher, Stephen M. Kelly, and Andrew Mansfield. "Scaling up of continuous-flow, microwave-assisted, organic reactions by varying the size of Pd-functionalized catalytic monoliths." Beilstein Journal of Organic Chemistry 7 (August 23, 2011): 1150–57. http://dx.doi.org/10.3762/bjoc.7.133.

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A product-scalable, catalytically mediated flow system has been developed to perform Suzuki–Miyaura reactions under a microwave heating regime, in which the volumetric throughput of a Pd-supported silica monolith can be used to increase the quantity of the product without changing the optimal operating conditions. Two silica monoliths (both 3 cm long), with comparable pore diameters and surface areas, were fabricated with diameters of 3.2 and 6.4 mm to give volumetric capacities of 0.205 and 0.790 mL, respectively. The two monoliths were functionalized with a loading of 4.5 wt % Pd and then sealed in heat-shrinkable Teflon® tubing to form a monolithic flow reactor. The Pd-supported silica monolith flow reactor was then placed into the microwave cavity and connected to an HPLC pump and a backpressure regulator to minimize the formation of gas bubbles. The flow rate and microwave power were varied to optimize the reactant contact time and temperature, respectively. Under optimal reaction conditions the quantity of product could be increased from 31 mg per hour to 340 mg per hour simply by changing the volumetric capacity of the monolith.
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Chen, Ai Bing, Wen Wei Zang, Chao Liu, Yan Yan Wang, Man Ling Jia, Bo Li, and Yi Feng Yu. "Preparation of Monolithic Transparent Mesoporous Silica and Mesoporous Onion-Like Carbon." Advanced Materials Research 557-559 (July 2012): 1518–21. http://dx.doi.org/10.4028/www.scientific.net/amr.557-559.1518.

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Large-sized, crack-free silica monoliths have been fabricated by a fast and convenient way via EISA method using P123 as soft template and 1-hexadecyl-3-methylimidazolium bromide (［C16mim］Br) as additive. The hydrogen bonds formed between ILs and the silano groups of silica gel play crucial roles in the form of the bulk, transparent silica monolith. The mesoporous structure onion-like carbon monoliths were prepared with the transparent silica monolith as template via the nanocasting technique. The mesoporous silica and carbon monoliths have been characterized by the XRD, HRTEM, N2sorption and elemental analysis. The results reveal that pore diameter of the mesoporous carbon about 3.47nm, and the specific surface area of carbon with a nitrogen content of 4.2%, can be tuned from 408.2-629.0m2/g. HRTEM shows that this carbon material with nanoonions structure.
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Thejaswini, Thurlapathi VL, and Deivasigamani Prabhakaran. "Synthesis of Mesoporous Titania–Silica Monolith Composites — A Comprehensive Study on their Photocatalytic Degradation of Acid Blue 113 Dye Under UV Light." International Journal of Nanoscience 15, no. 05n06 (October 2016): 1660012. http://dx.doi.org/10.1142/s0219581x16600127.

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The present work deals with the synthesis of bi-continuous macro and mesoporous crack-free titania–silica monoliths, with well-defined structural dimensions and high surface area. The work also highlights their potential photocatalytic environmental applications. The highly ordered titania–silica monoliths are synthesized through direct surface template method using organic precursors of silica and titania in the presence of surface directing agents such as pluronic P123 and PEG, under acetic acid medium. The monoliths are synthesized with different Ti/Si ratios to obtain monolithic designs that exhibit better photocatalytic activity for dye degradation. The titania–silica monoliths are characterized using XRD, SEM, EDAX, FT-IR, TG–DTA and BET analysis. The photocatalytic activity of the synthesized monoliths is tested on the photodegradation of a textile dye (acid blue 113). It is observed that the monolith with 7:3 ratio of Ti/Si showed significant photocatalysis behavior in the presence of UV light. The influence of various physico-chemical properties such as, solution pH, photocatalyst dosage, light intensity, dye concentration, effect of oxidants, etc. are analyzed and optimized using a customized photoreactor set-up. Under optimized conditions, the monoliths exhibited superior degradation kinetics, with the dye dissipation complete within 10[Formula: see text]min of photolysis. The mesoporous catalysts are recoverable and reusable up to four cycles of repeated usage.
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Buntem, Radchada, and Kewarin Pramual. "Amine-Functionalized Silica Monolith as a Copper Ion Adsorbent." Advanced Materials Research 1131 (December 2015): 198–202. http://dx.doi.org/10.4028/www.scientific.net/amr.1131.198.

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Amine-functionalized silica monoliths were prepared by co-condensation between tetraethyl orthosilicate and N-[3-(trimethoxysilyl) propyl] ethylenediamine.The mixture between ethanol, H2O, tetraethyl orthosilicate, N-[3-(trimethoxysilyl) propyl] ethylenediamine and 1M HCl was stirred for 1 hour at room temperature to obtain a clear silica sol. 1.2 g of the sol was poured into plastic vial with the paraffin cover and left for 2 days for the polymerization process to obtain the gel. The disc-shape gel was dried in the oven at 50 °C for 10 hours. The silica monolith obtained was weighed and analyzed by IR spectroscopy and BET method. The disc-shape silica monoliths were further used for copper ion adsorption studies. The factors affecting the copper ion adsorption like pH, copper ion concentration and metal ion interference were studied. The pHs of CuCl2 aqueous solutions were varied from pH 2 to pH 6. While the Cu2+ concentrations under this study were 10-1, 10-2, 10-3, 10-4, 10-5 and 10-6 M. The cationic interferences used were Cd2+ and Ni2+. For the copper ion concentration, the higher the concentration results in the higher adsorption capacity. At the lower concentrations like 10-4, 10-5 and 10-6 M, a complete adsorption was obtained. The color of the Cu2+ - loaded monolith was changed to blue due to the complex between amino groups on the silica and the Cu2+ as evidenced by IR analysis. The monolith after adsorption was also analyzed by SEM/EDS. The inferences like Cd2+ and Ni2+ affect the Cu2+ adsorption at different degree. The desorption could be successfully performed by using 0.1 M HCl solution.
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Im, Hee-Jung, Byunghwan Lee, Suree S. Brown, and Sheng Dai. "Neutron Scintillators of Transparent Silica Xerogel Monolith via a Sealed Container System and π–π Interactions." Journal of Nanoscience and Nanotechnology 7, no. 11 (November 1, 2007): 3784–87. http://dx.doi.org/10.1166/jnn.2007.016.

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Transparent crack-free lithiated sol–gel scintillating monoliths were developed by taking advantage of a sealed container system for a syneresis and the π–π interactions between sol–gel components and organic fluors to yield a better homogeneity and scintillating efficiency. The transparency of the resulting materials indicates that the new scintillating material composites are mesoscopically dispersed. The silica monolith can be prepared without cladding the monolith with an engineering plastic such as a poly(ether ether ketone) (PEEK) or a liquid mounting medium. A successful detection of neutron particles by using these lithiated scintillating monoliths was demonstrated.
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Im, Hee-Jung, Byunghwan Lee, Suree S. Brown, and Sheng Dai. "Neutron Scintillators of Transparent Silica Xerogel Monolith via a Sealed Container System and π–π Interactions." Journal of Nanoscience and Nanotechnology 7, no. 11 (November 1, 2007): 3784–87. http://dx.doi.org/10.1166/jnn.2007.18072.

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Transparent crack-free lithiated sol–gel scintillating monoliths were developed by taking advantage of a sealed container system for a syneresis and the π–π interactions between sol–gel components and organic fluors to yield a better homogeneity and scintillating efficiency. The transparency of the resulting materials indicates that the new scintillating material composites are mesoscopically dispersed. The silica monolith can be prepared without cladding the monolith with an engineering plastic such as a poly(ether ether ketone) (PEEK) or a liquid mounting medium. A successful detection of neutron particles by using these lithiated scintillating monoliths was demonstrated.
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Spilstead, Kara B., Stephen J. Haswell, Neil W. Barnett, Xavier A. Conlan, Paul G. Stevenson, and Paul S. Francis. "Development of a resin based silica monolithic column encapsulation." Analytical Methods 7, no. 12 (2015): 4908–11. http://dx.doi.org/10.1039/c5ay00722d.

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A robust technique for the encapsulation of silica-monolithic columns into microfluidic devices. This new approach overcomes the deleterious wall-effects of previous approaches and enables direct fluidic connection to the monolith using standard fittings.
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Lu, Lu, Yu Lei Wei, Jie Lin, and Lei Qian. "Fabrication of Silica Monoliths with Hierarchically Porous Structure from Freeze-Drying." Materials Science Forum 814 (March 2015): 76–80. http://dx.doi.org/10.4028/www.scientific.net/msf.814.76.

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This paper provides a novel route to prepare silica monoliths with hierarchical porous structure via freeze drying. In this method, macroporous silica monoliths were first produced by freeze-drying and calcination. By adjusting the concentration of cetyltrimethylammonium bromide in ethylsilicate, a layer of mesoporous thin film was attached on the macroporous silica monolith. The structural characterization of the hierarchical porous monoliths were studied by field emission scanning electron microscopy, mercury porosimeter and nitrogen adsorption-desorption techniques (BET). It turned out that the pore distribution of the obtained monoliths was ranged from 3.72 nm to 23.21nm and the maximum specific surface area calculated from BET was about 288 m2/g, which indicated the existence of hierarchical structure in the obtained material.
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Dissertations / Theses on the topic "Silica monolith"

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Smith, Jennifer Houston. "Chromatographic Properties of Silica-Based Monolithic HPLC Columns." Diss., Virginia Tech, 2002. http://hdl.handle.net/10919/29953.

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Silica-based monolithic HPLC columns contain a novel chromatographic support in which the traditional particulate packing has been replaced with a single, continuous network (monolith) of porous silica. The main advantage of such a network is decreased backpressure due to macropores (2 μM) throughout the network. This allows high flow rates, and hence fast analyses that are unattainable with traditional particulate columns. The Chromolith SpeedROD™ (EM Science, Gibbstown NJ) is a commercially available silica-based monolithic column. This work investigated the chromatographic properties of the 50x4.60 mm (ODS) SpeedROD™. Data fit to the van Deemter equation (mean square error=0.834) indicated that the van Deemter model was valid for monolithic columns. An effective particle size of 4 μM for the SpeedROD™ column was assigned by comparing the minimum of van Deemter curves with a series of particulate columns having various particle diameters. Separation Impedance (E), an empirically derived measure of column performance, was calculated as an alternate method of evaluating column efficiency. Data collected using this model confirmed monolithic columns behaves as a (more efficient) 3 μM column. A series of experiments were designed to compare the effects of mobile phase strength and mobile phase viscosity between the SpeedROD™ column and a particulate column. The results indicated both solvent strength and viscosity have effects on the monolithic column at the optimum linear velocity. A fast (90 s) HPLC method was developed using the SpeedROD™ column and a seven-component test mixture with a large range of hydrophobicities. The precision for both retention time and peak area was measured at high linear velocities (8 mL/min) and the percent relative standard deviation (RSD) calculated. Column to column reproducibility (n=6) was measured. The overall percent RSD ranged from 0.25% to 4.56% for retention time and from 1.08% to 6.77% for peak area. Run to run reproducibility (n=15) was measured for all six columns. Averages ranged for retention time from 0.89% to 5.09% RSD and for peak area from 4.65% to 6.18% RSD. Applications for the SpeedROD™ column with various sample types were developed and discussed. These methods demonstrated the effectiveness of the SpeedROD™ at fast flow rates.
Ph. D.
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El-Debs, Racha. "Synthèse de colonnes capillaires de monolithes de silice et développement d’un procédé photochimique simple, localisable et polyvalent de fonctionnalisation de leur chimie de surface." Thesis, Lyon 1, 2013. http://www.theses.fr/2013LYO10254.

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Ce manuscrit est consacré à l’élaboration et à la photofonctionnalisation des monolithes de silice pour les techniques séparatives miniaturisées. La partie bibliographique situe d’abord l’intérêt des monolithes dans les techniques séparatives miniaturisées. L’état d’art sur l’utilisation des monolithes de silice dans ces techniques séparatives est ensuite établi en portant une attention particulière sur leur utilisation dans l’analyse d’échantillons biologiques et/ou environnementaux (préparation d’échantillons couplée aux méthodes séparatives ou utilisation de colonne de grande longueur). Un descriptif de la synthèse des monolithes de silice par le procédé sol gel est ensuite détaillé. Enfin, une étude des différentes méthodes de fonctionnalisation des monolithes de silice est présentée. L’optimisation des paramètres expérimentaux de la synthèse sol-gel a conduit à un procédé de synthèse robuste et répétable de capillaires monolithiques de silice de grandes longueurs et d’efficacités élevées (efficacités de l’ordre de 160 000-200 000 plateaux/m). Le travail expérimental s’est ensuite orienté sur l’optimisation de procédés de fonctionnalisation par voie thermique et sur le développement de nouveaux procédés de photopolymérisation ou de photografting par « photo click chemistry ». Les résultats obtenus dans des modes chromatographiques variés après photofonctionnalisation avec différents monomères montrent que ces procédés sont polyvalents et qu’un contrôle des paramètres permet de conserver les performances chromatographiques du matériau de départ. Outre sa simplicité et sa rapidité, cette approche permet de définir et de localiser différentes chimies de surface au sein d’une même colonne. Cette spécificité a été mise à profit pour le couplage en ligne dans une colonne de nanochromatographie, d’une étape de préconcentration avec une étape de séparation de neuropeptides modèles
This manuscript is dedicated to the development and functionalization of monolithic silica stationary phases for miniaturized separation techniques. The bibliographic section first summarizes the interest of monolithic phases for the development of miniaturized separation techniques and their advantages over their particulate counterparts (small particles or core shell ones). The state of the art on the use of silica monolithic columns in separation techniques is then established, with a focus on their use in the analysis of biological and/or environmental samples (coupling sample preparation with an analysis method or using long columns). Then a detailed description of the sol gel synthesis of monolithic silica is presented. Finally, a study of different established methods of functionalization of silica monoliths is presented and the potential of photofunctionalization is highlighted for the rapid and homogeneous in-situ functionalization of monolithic capillaries. The experimental part focuses first on the development and optimization of a robust process of synthesis of monolithic silica capillary columns (efficiencies around 160 000-200 000 plates/m). The work is then focused on the improvement of classical functionnalization processes and on the development of new photofunctionalization ways (photopolymerization and photo click chemistry) of silica monolithic columns. The results obtained after photofonctionnalisation in various chromatographic modes (from ion exchange to reversed phase and HILIC) mode with different monomers show that these methods are versatile and that the control of the parameters allows keeping the chromatographic performances of the starting material. Besides its simplicity and speed, this approach allows to define and to locate different surface chemistries in the same column. This specificity has been exploited to the in-line coupling a preconcentration step with a separation step in a single column, for the separation of model neuropeptides
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Khattab, Amin Khalid. "Fabrication, functionalization and characterization of silica monolith for forensic chemistry applications." Thesis, University of Hull, 2014. http://hydra.hull.ac.uk/resources/hull:10112.

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The physiochemical properties of silica monolith make it an ideal base material for drugs extracting, pre-concentrating and separation from biological samples which can interact not only with molecules but also with ions and atoms. However, the fabrication of silica monoliths still has some problems, such as cost, limited capacity and fabrication and modification methodology, which can be time consuming and labour intensive. Structure evolution of silica monolith was studied in microwave and conventionally processed samples over the temperature range from 25 to 70 oC. The samples were produced using sol-gel processing. The microwave process was performed using a single mode cavity at 2.45GHz. Characterization of produced silica monoliths were carried out using a variety of techniques, including Scanning Electron Microscopy (SEM) analysis, EDX analysis, BET and BJH analysis. The data obtained showed that structural differences do exist between conventional and microwave processed samples. It was found however, that microwave based fabrication offered a significantly quicker (11 min) gelation process, compared to those obtained using the thermal heated oven methodology (4,320 min). The silica monolithic surfaces were modified with three different phases C₁₈, gold nanoparticles and graphene which received a thermal treatment at different programmed powers in two different ovens, conventional and microwave. Three substantial variance were also identified from the structural characterization of modified silica surfaces processed using microwave heating and conventional heating methods: 1- The use of microwave heating during C₁₈ surface modification improved not only the attachment of C₁₈ groups to the silica surface but also increased the extraction efficiency of caffeine and eserine from standard solutions (102 % and 97 %, respectively). 2- The fabrication of gold nanoparticles-NH2-silica monolith using microwave heating was found to improve the sensitivity and selectivity of modified silica surface and make possible to extract, detect and quantify more than one type of drugs of abuse at the same time within few minutes. 3- Using graphene-silica monolith makes the extraction of non-polar, polar, very polar and water-soluble analytes, based on both hydrophobic and electronic interactions, easy and simple. Fabrication and modification of silica monoliths using microwave heating make the sol-gel procedure much faster and easier and allow for non-polar, polar, very polar and water-soluble analytes to be extracted more efficiently to produce accurate and precise results compared to the conventional method for fabrication and modification of silica monoliths using three phases (C₁₈, gold nanoparticles and graphene). Finally, this technique make the modified silica monolithic column capable to extract selected drugs of abuse from biological samples and produce qualitative and quantitative results at the same time using chemiluminescence based immunoassays or HPLC-UV.
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CALDAROLA, DARIO. "Silica beds and silica monoliths for pollutants removal and HPLC." Doctoral thesis, Politecnico di Torino, 2013. http://hdl.handle.net/11583/2506223.

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This PhD thesis investigates mesostructured porous silica as a system for removal of pollutants and high performance liquid chromatography (HPLC). In these fields typically the materials used consist of a silica substrate modified with a compound, which has a high selectivity towards the analyte of interest. In this thesis two silica modifiers are proposed: cetyltrimetylammonium bromide (CTABr) and glyphosate. The CTABr was actually the cationic surfactant used as template for the mesostructure, which was not removed from the silica framework as it usually is by calcination. This surfactant was used for the retention of haloacetic acids (HAACs) and nitrate ion. The glyphosate is an aminoacid present in many commercial herbicides and it has a high complexation capability towards metals. It was linked onto the silica surface using an appropriate reagent, the 3-glycidoxypropyltrimethoxysilane. The behavior of HAACs, NO3- and metals has been investigated because they are some of the most dangerous and monitored pollutants in water. The chosen surface modifiers have been combined with two different systems: silica particles and silica monoliths. The silica particles have been used until the late 1990s for HPLC columns packing, and they are nowadays mainly used as adsorbents of compounds due to their elevated capacity and strong retention capability. The silica monoliths have become the state of the art in HPLC, because of their better mass transfer, higher efficiency and lower analysis time compared to particle packed columns. Four materials have been prepared combining the two morphologies with each modifier. Physical-chemical characterization has been performed using several techniques (FTIR, N2 isotherms at 77 K, SEM-EDS, XPS and TGA) then the materials capabilities have been investigated in their respective fields of application. The interesting results obtained with these brand new adsorbents may have a high impact over the fields of waters purification and analysis, which is one of the recent most important topics due to the huge raise of contaminants during the last 150 years.
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Roux, Richard. "Synthèse de phase stationnaires monolithiques de silice hybrides pour les techniques séparatives miniaturisées." Thesis, Lyon 1, 2009. http://www.theses.fr/2009LYO10208.

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Ce manuscrit est consacré à la synthèse par procédé sol-gel et à la caractérisation de matériaux monolithiques de silice hybrides pour les techniques séparatives miniaturisées : nano-chromatographie en phase liquide (nano-CPL), électrochromatographie capillaire (ECC) et microsystèmes séparatifs. La partie bibliographique situe les axes de développement récents des techniques séparatives : l’augmentation de l’efficacité par unité de temps, l’augmentation de la capacité de pics et la miniaturisation de ces techniques. Après un descriptif détaillé de l’évolution des techniques séparatives lors de ces dernières années, une attention particulière est portée sur les phases stationnaires monolithiques à base de silice. Enfin, une étude approfondie des différentes fonctionnalisations de ces monolithes de silice met en évidence l’intérêt porté aux monolithes de silice hybrides en termes de simplification du protocole de synthèse. La partie expérimentale est ainsi axée sur le développement et la caractérisation de ces monolithes de silice hybrides dédiés à la chromatographie à polarités de phases inversée. Dans un premier temps, la synthèse de monolithes de silice hybrides C3 illustre la possibilité de synthétiser par voie sol-gel (100% aqueux) un monolithe de silice fonctionnalisé et performant en une seule étape (« one pot »). Dans un second temps, ce type de procédé est employé et optimisé afin de synthétiser des capillaires monolithiques de silice hybrides C8 présentant des performances équivalentes à leurs homologues C8 préparés en deux étapes (synthèse puis greffage) et comparables à des colonnes particulaires (d particules 5 μm)
This manuscript is dedicated to the synthesis (via sol-gel process) and caracterization of hybrid monolithic silica for miniaturized separation techniques : nano-liquid chromatography (nano-LC), capillary electrochromatography (CEC) and microchips. The bibliography part deals with the recent axis of development of these separatives techniques : increase of efficiency per time unit, increase of peak capacity and miniaturisation of these techniques. After an overview of this evolution, the manuscript is focused on the silica monolithic stationnary phases. Finally, a detailed study on the different kinds of protocol fonctionnalization of these silica monoliths highlights the advantage of simplifying the synthesis using a single step protocol (« one pot »). The experimental part is also focused on this kind of single step protocol so as to synthesize hybrid silica monoliths dedicated to the reversed phase mode in chromatography. First, the synthesis of hybrid C3 silica monoliths shows the ability to synthesize a functionnalized silica monolith via a single step sol gel process (« one pot »). Then, this kind of process is used and optimized in order to synthesize a hybrid C8 silica monolithic into capillaries. These stationary phases allowed reaching performances similar to those synthesized in two steps (sol-gel process and grafting) and to the particulate columns (5 μm)
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Zhang, Tong. "Preparation, characterization, modification and application of hybrid silica-based monolith in capillary electrochromatography." Thesis, University of Strathclyde, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.487859.

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Hybrid silica-based monoliths (prepared with tetramethoxysilane and methyltrimethoxysilane 3:1 v/v) were prepared in 100μm I.D. capillaries using a sol-gel technique. Although good electrochromatographic repeatability was shown on a single hybrid silica-based monolithic capillary poor reproducibility of the preparation was evidenced by the small number of good quality columns obtained in this study.
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Marechal, Audrey. "Colonnes monolithiques multimodales photofonctionnalisées dédiées aux techniques séparatives miniaturisées." Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10308/document.

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Une des évolutions dans le domaine de l'analyse chimique concerne la miniaturisation des systèmes d'analyse. Cette tendance s'accompagne du développement de nouvelles approches expérimentales basées, par exemple, sur l'intégration de plusieurs étapes analytiques, couplées en ligne en système miniaturisé. Cette intégration, en ligne, d'étapes mettant en jeu des mécanismes de séparation différents et généralement orthogonaux, implique cependant d'être capable de définir des zones (segments de colonne vides et/ou remplis de phase stationnaire) présentant des chimies de surface adaptées. L'approche choisie pour la préparation de ces colonnes " multimodales ", repose sur (1) la synthèse d'un monolithe de silice poreux "générique " dans des tubes capillaires de quelques dizaines de microns de diamètre interne et (2) la modification de surface localisée dans le capillaire permettant d'apporter des propriétés de surface complémentaires. Dans le cadre de cette thèse, deux procédés de fonctionnalisation innovants, initiés par photochimie, ont été développés pour la préparation des colonnes multimodales miniaturisées : la photopolymérisation, basée sur des réactions de polymérisation radicalaire, et la " photoclick chemistry ", basée sur un greffage radicalaire contrôlé (et non plus une polymérisation). Un état de l'art de leur utilisation en sciences séparatives a été dressé pour chacun des procédés, afin de guider le choix des stratégies de greffage. Après une optimisation des conditions de greffage, les résultats présentés dans ce manuscrit montrent que ces procédés de fonctionnalisation sont rapides (fonctionnalisation en quelques minutes), efficaces, polyvalents (transposables à de multiples greffons) et localisables. Leurs potentiels respectifs dans la préparation des colonnes multimodales ont ensuite été démontrés pour la préconcentration/séparation en ligne de plusieurs composés. L'approche par " click chemistry " qui permet un meilleur contrôle du greffage, a été étendue au greffage de biomolécules pour la préparation de supports d'immunoaffinité. Ainsi, une colonne multimodale composée d'une première zone remplie de monolithe photogreffée avec des aptamères et une deuxième zone vide a été préparée pour la préconcentration/séparation électrocinétique en ligne de l'Ochratoxine A
Miniaturization of analytical processes is a general trend in analytical chemistry. Such trend is driven by the development of new experimental approaches based, for example, on hyphenated analytical steps or techniques. The in-line coupling of different and generally orthogonal/complementary separation mechanisms at the microscale, is dependent on the capability to define functional segments (open column segments and/or filled with stationary phase). Preparation of such "multimodal" capillary columns is based on (1) the in-capillary synthesis of a "generic" porous silica monolith and (2) on its localized chemical surface modification to define specific functional segments. Herein, two innovative photo-functionalization processes have been investigated for the preparation of multimodal miniaturized columns. The former, called photopolymerization is based on acrylate free radical polymerization reactions while the latter, called photografting, implements the thiol-ene "photoclick chemistry" reaction. These photo-initiated processes, after optimization, prove to be rapid (within few minutes), versatile (adapted to the grafting of various monomers) and localizable. Photopolymerization of acrylate monomers on activated silica monolith (using ?-methacryloxypropyltrimethoxysilane) gives rise to highly retentive columns due to the polymeric nature of the layer obtained. Photografting of octadecanethiol on vinylized silica columns leads to monolayer-like coating. The preparation of dedicated multimodal columns using such approaches was then successfully applied to the in-line preconcentration / separation of neuropeptides and preconcentration / fractionation of various neutral and charged compounds. The "click chemistry" approach which allows a better control of the reaction, has been extended to the grafting of biomolecules for the preparation of immunoaffinity supports. Thus, a multimodal column composed a 1-cm length aptamer-functionalized monolith at the entrance of a CZE open capillary has been prepared and successfully applied to the in-line preconcentration/electrokinetic separation of Ochratoxin A in white wine and beer
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Izaak, T. I., D. О. Martynova, V. V. Maas, E. М. Slavinskaya, А. I. Boronin, and Y. W. Chen. "Synthesis and Properties of Ag / CuO / SiO2 Nanocomposites." Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35611.

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In this paper the composites Ag / SiO2 with regularly distributed in bulk matrix silver and copper oxide nanoparticles were synthesized. Herewith, copper ions was introduced into porous support at the stage of sol-gel synthesis. Sample Ag / CuO / SiO2 was tested by the catalytic reaction of CO oxidation and com-pared with Ag / SiO2. It was revealed that sample with introduced copper show lower activity .This fact can be explained by formation of silver cuprate during preparation of composite Ag / CuO / SiO2. Treatment by reaction mixture (CO and O2) led to release of silver in ionic, clusters and metal states that increased cata-lytic activity of the composite. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35611
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Souza, Israel Donizéti de. "Desenvolvimento de fases monolíticas de sílica híbrida para microextração em sorvente empacotado (MEPS) de fármacos em amostras de plasma e análise por cromatografia líquida acoplada a espectrometria de massas em tandem (LC-MS/MS)." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/59/59138/tde-02092015-093155/.

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Segundo a Organização Mundial da Saúde (OMS), a esquizofrenia é reconhecida como um transtorno neuropsiquiátrico grave que afeta mais de 21 milhões de pessoas em todo o mundo. Para diminuir os sintomas associados a esta doença, a maioria dos pacientes esquizofrênicos fazem uso concomitantemente de antipsicóticos, antidepressivos, ansiolíticos e anticonvulsivantes. O desenvolvimento de métodos analíticos para a determinação desses fármacos em fluidos biológicos é importante para ajustar as doses administradas, minimizar os efeitos adversos e verificar a anuência do paciente à terapia. A química analítica moderna tem se direcionado para a simplificação, através da miniaturização dos sistemas analíticos. Neste contexto, pode-se destacar a técnica de microextração em sorvente empacotado (MEPS). O desenvolvimento de novas fases extratoras para MEPS, como, os monolitos de sílica híbrida permitem pré-concentração seletiva dos analitos. Neste projeto monolitos de sílica híbrida funcionalizados com grupos aminopropil ou cianopropil foram sintetizados pelo processo sol-gel. Estes monolitos apresentaram estrutura contínua, uniforme e porosa, como evidenciado pelas imagens de microscopia eletrônica de varredura (MEV). As análises de espectroscopia vibracional na região do infravermelho por transformada de Fourier (FTIR) dos monolitos de sílica híbrida exibiram picos facilmente identificáveis, característicos dos grupos cianopropil e aminopropil. Estes monolitos foram avaliados como fase estacionária para a MEPS para a determinação de fármacos em amostras de plasma por cromatografia líquida acoplada a espectrometria de massa em Tandem (LC-MS/MS). As variáveis MEPS (influência do pH na sorção dos analitos, número de ciclos aspirar/dispensar, etapa de limpeza do sorvente e solvente de eluição) foram otimizadas para aumentar a eficiência da extração. Em comparação com a fase de sílica híbrida aminopropil, a fase de sílica híbrida cianopropil apresentou maior capacidade de sorção para os fármacos em estudo. O método desenvolvido, MEPS/LC-MS/MS, empregando a fase extratora de sílica híbrida cianopropil, apresentou linearidade adequada com concentrações que variaram desde o limite inferior de quantificação (0,05-1,00 ng.mL-1) até o limite superior de quantificação (40-10.500 ng.mL-1) com coeficientes de determinação (R2) maiores do que 0,9955. Este método apresentou precisão com coeficientes de variação (CV) inferiores a 14% e exatidão com erro padrão relativo (EPR) de -12 a 14%. O método MEPS/LC-MS/MS foi aplicado com êxito para análise simultânea de cinco antipsicóticos (olanzapina, quetiapina, clozapina, haloperidol e clorpromazina), em combinação com sete antidepressivos (mirtazapina, paroxetina, citalopram, sertralina, imipramina, clomipramina e fluoxetina), dois anticonvulsivantes (carbamazepina e lamotrigina) e dois ansiolíticos (diazepam e clonazepam) em amostras de plasma de pacientes esquizofrênicos para fins de monitorização terapêutica.
According to World Health Organization (WHO), schizophrenia is recognizably a devastating neuropsychiatric disorder that affects more than 21 million people worldwide. To lessen the symptoms associated with the disease, most schizophrenic patients use other classes of drugs such as antidepressants, anxiolytics, and anticonvulsants concomitantly with antipsychotics. Developing analytical methods to quantify these drugs in biological fluids is important in therapeutic drug monitoring (TDM) to adjust doses, minimize adverse effects, and check patient adherence to the therapy. Regarding miniaturization and automation, microextraction by packed sorbent (MEPS) is a promising sample preparation technique. Sample preparation of biological matrixes is an important step in analytical processes: it removes endogenous components from the sample and pre-concentrates trace-level analytes. The development of new phases for MEPS such as the hybrid silica monoliths allows selective pre-concentration of the analytes. The present study reports on the synthesis of two hybrid silica monoliths functionalized with aminopropyl or cyanopropyl groups by the solgel process; evaluates these monoliths as selective stationary phase for MEPS to determine drugs in plasma samples by liquid chromatography-tandem mass spectrometry (LC-MS/MS); and discusses important factors (influence of pH on the sorption of analytes, number of draw/eject cycles, washing step, and elution solvent) related to the optimization of MEPS efficiency. The prepared hybrid silica monoliths consisted of a uniform, porous, and continuous silica monolithic network, as shown by scanning electron microscopy (MEV) images. The Fourier-transform infrared spectroscopy (FTIR) spectra of the hybrid silica monoliths displayed readily identifiable peaks, characteristic of the cyanopropyl and aminopropyl groups. Compared with the aminopropyl hybrid silica phase, the cyanopropyl hybrid silica phase exhibited higher binding capacity for most of the target drugs. The developed method, MEPS/LC-MS/MS, afforded adequate linearity at concentrations ranging from the lower limit of quantification (0.05 to 1.00 ng.mL-1) to the upper limit of quantification (40 to 10500 ng.mL-1); the coefficients of determination (R2) were higher than 0.9955. The precision of the method presented coefficients of variation (CV) lower than 14%; the relative standard error (RSE) of the accuracy ranged from -12 to 14%. The developed MEPS/LC-MS/MS method allowed for simultaneous analysis of five antipsychotics (olanzapine, quetiapine, clozapine, haloperidol, and chlorpromazine) in combination with seven antidepressants (mirtazapine, paroxetine, citalopram, sertraline, imipramine, clomipramine, fluoxetine), two anticonvulsants (carbamazepine and lamotrigine), and two anxiolytics (diazepam and clonazepam) in plasma samples from schizophrenic patients, which should be valuable for TDM purposes.
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Fleury, Joachim. "Développement de phases stationnaires monolithiques pour la chromatographie en phase gazeuse miniaturisée ultra-rapide." Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066652.

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La miniaturisation des systèmes conventionnels de chromatographie en phase gazeuse (CPG) est d’un intérêt majeur pour de nombreuses applications. L'objectif est d'aboutir à des améliorations des systèmes existants, en termes de portabilité et d’autonomie, mais aussi en termes de durée d’analyse et de coût. In fine, ces systèmes miniaturisés de CPG pourraient être utilisés directement sur le terrain pour de l’analyse en continu presque en temps réel. Dans ce contexte, ce projet de thèse a consisté à développer des phases stationnaires monolithiques à base de silice afin de séparer, de manière ultra-rapide, des composés très volatils tels que des alcanes légers C1-nC5. Dans une première partie, la synthèse d’un monolithe de silice in situ dans des capillaires de 75 µm d.i. a été optimisée via une approche sol-gel de manière à adapter la perméabilité, et donc la structure macroporeuse des matériaux aux écoulements gazeux. Nous avons pu ainsi obtenir, pour la première fois, des séparations rapides C1-nC5 en CPG à des pressions conventionnelles en tête de colonne (Pin < 4 bar). Le second volet de cette thèse a consisté à optimiser et contrôler l’état de surface des monolithes par l’élaboration de deux traitements post-synthèse différents ayant pour objectif l’élimination du porogène organique résiduel. Des séparations C1-nC5 ultra-rapides (à l’échelle de quelques secondes) à haute température et en régime isotherme ont pu être obtenues en raison de la rétention et de l’efficacité élevées des matériaux. Enfin, le rendement, la répétabilité et la reproductibilité de la synthèse des monolithes de silice ont été étudiés afin d’évaluer leur potentielle fabrication à grande échelle
The miniaturization of conventional gas chromatography (GC) systems is of major interest for many applications. The aim is to achieve improvements in existing systems, in terms of portability and autonomy, but also in terms of analysis time and cost. Ultimately, these miniaturized GC systems could be field-portable for near real-time continuous monitoring. In this context, this PhD project consisted in developing silica-based monolithic stationary phases in order to obtain ultra-fast separation of very volatile compounds such as C1-nC5 light alkanes. First of all, in situ synthesis of a silica monolith in capillaries of 75 μm i.d. has been optimized via a sol-gel approach in order to adapt the permeability, and therefore the macroporous structure of the materials, for gas flows. For the first time, fast C1-nC5 separations were obtained at conventional column inlet pressures (Pin < 4 bar). The second part of this PhD project consisted in optimizing and controlling the surface state of the monoliths by the development of two different post-synthesis treatments with the objective of eliminating the residual organic porogen. Ultra-fast C1-nC5 separations (at a few seconds) at high temperature and isothermal conditions were achieved due to the high retention and efficiency of the materials. Finally, the yield, repeatability and reproducibility of silica monoliths synthesis were studied in order to evaluate their potential large-scale production
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Books on the topic "Silica monolith"

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Unger, Klaus K., Nobuo Tanaka, and Egidijus Machtejevas, eds. Monolithic Silicas in Separation Science. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527633241.

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Smått, Jan-Henrik. Hierarchically porous silica, carbon, and metal oxide monoliths: Synthesis and characterization. Turku: Åbo Akademi University, 2005.

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Unger, K. K., Nobuo Tanaka, and Egidijus Machtejevas. Monolithic silicas in separation science: Concepts, syntheses, characterization, modeling and applications. Weinheim: Wiley-VCH Verlag GmbH, 2011.

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A, Salem Jonathan. Strength and toughness of monolithic and composite silicon nitrides. [Washington, DC]: National Aeronautics and Space Administration, 1990.

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1960-, Salem J. A., and United States. National Aeronautics and Space Administration., eds. Comparison of dynamic fatigue behavior between SiC whisker-reinforced composite and monolithic silicon nitrides. [Washington, DC]: National Aeronautics and Space Administration, 1991.

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Vasconcelos, Wander Luiz. Topological evolution and properties of sol-gel silica monoliths. 1989.

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Tanaka, Nobuo, Egidijus Machtejevas, and Klaus K. Unger. Monolithic Silicas in Separation Science: Concepts, Syntheses, Characterization, Modeling and Applications. Wiley & Sons, Incorporated, John, 2011.

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Tanaka, Nobuo, Egidijus Machtejevas, and Klaus K. Unger. Monolithic Silicas in Separation Science: Concepts, Syntheses, Characterization, Modeling and Applications. Wiley & Sons, Incorporated, John, 2010.

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Tanaka, Nobuo, Egidijus Machtejevas, and Klaus K. Unger. Monolithic Silicas in Separation Science: Concepts, Syntheses, Characterization, Modeling and Applications. Wiley & Sons, Incorporated, John, 2010.

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Tanaka, Nobuo, Egidijus Machtejevas, and Klaus K. Unger. Monolithic Silicas in Separation Science: Concepts, Syntheses, Characterization, Modeling and Applications. Wiley & Sons, Limited, John, 2011.

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Book chapters on the topic "Silica monolith"

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Yuan, Ruijuan, and Guosheng Ding. "Enantioseparations in Capillary Electrochromatography Using Sulfated Poly β-Cyclodextrin-Modified Silica-Based Monolith as Stationary Phase." In Methods in Molecular Biology, 489–503. Totowa, NJ: Humana Press, 2012. http://dx.doi.org/10.1007/978-1-62703-263-6_31.

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Chaudhuri, S. Ray, and Arnab Sarkar. "Large Silica Monoliths." In Sol-Gel Optics, 83–107. Boston, MA: Springer US, 1994. http://dx.doi.org/10.1007/978-1-4615-2750-3_4.

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Ashman, Keith. "Silica Monolithic Columns and Mass Spectrometry." In Monolithic Silicas in Separation Science, 273–83. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527633241.ch14.

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Nakanishi, Kazuki. "Synthesis Concepts and Preparation of Silica Monoliths." In Monolithic Silicas in Separation Science, 9–33. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527633241.ch2.

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Kimerling, L. C., L. Dal Negro, S. Saini, Y. Yi, D. Ahn, S. Akiyama, D. Cannon, et al. "Monolithic Silicon Microphotonics." In Topics in Applied Physics, 89–120. Berlin, Heidelberg: Springer Berlin Heidelberg, 2004. http://dx.doi.org/10.1007/978-3-540-39913-1_3.

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Tanaka, Nobuo, and Klaus K. Unger. "The Basic Idea and the Drivers." In Monolithic Silicas in Separation Science, 1–7. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527633241.ch1.

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Taha, Mohammed, Abdelkarem Abed, and Sami El Deeb. "Quality Control of Drugs." In Monolithic Silicas in Separation Science, 189–205. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527633241.ch10.

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Nesterenko, Pavel N., and Paul R. Haddad. "Monolithic Stationary Phases for Fast Ion Chromatography." In Monolithic Silicas in Separation Science, 207–30. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527633241.ch11.

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Chankvetadze, Bezhan. "Monolithic Chiral Stationary Phases for Liquid-Phase Enantioseparation Techniques." In Monolithic Silicas in Separation Science, 231–48. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527633241.ch12.

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Hara, Takeshi, Kosuke Miyamoto, Satoshi Makino, Shohei Miwa, Tohru Ikegami, Masayoshi Ohira, and Nobuo Tanaka. "High-Speed and High-Efficiency Separations by Utilizing Monolithic Silica Capillary Columns." In Monolithic Silicas in Separation Science, 249–72. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527633241.ch13.

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Conference papers on the topic "Silica monolith"

1

Bhattacharyya, Arpita, and Catherine Klapperich. "Fabrication of Polymeric Microfluidic Device for On-Chip Isolation of Nucleic Acids." In ASME 3rd International Conference on Microchannels and Minichannels. ASMEDC, 2005. http://dx.doi.org/10.1115/icmm2005-75200.

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A microfluidic chip-based solid phase extraction method for isolation of nucleic acids is demonstrated. The chip was fabricated in a cyclic polyolefin by hot embossing with a master. The solid phase was made by in-situ UV polymerization of a monolithic column impregnated with silica particles, and separation was achieved due to irreversible binding of the nucleic acids to the silica particles in the monolith. The porous monolithic column was formed within the channels of the device by photoinitiated polymerization of a mixture of methacrylate and dimethacrylate monomers, UV sensitive free radical initiator and porogenic solvent. The channel surface was photografted with a thin interlayer polymer prior to preparation of the monolith in the channel. The grafted layer covalently attached the monolith and prevented the formation of voids between the monolith and the channel surface. The solid-phase prepared by this method allowed for successful extraction and elution of nucleic acids.
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Wang, Ping, Zilin Chen, and Hsueh-Chia Chang. "A New Monolithic Electrokinetic Pump With Bubble-Less Design." In ASME 3rd International Conference on Microchannels and Minichannels. ASMEDC, 2005. http://dx.doi.org/10.1115/icmm2005-75145.

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An electrokinetic micro-pump fabricated by a sol-gel process has been designed which can be used as a robust fluid-driving unit on a chip-scale analytical system. An overall monolithic silica matrix with morphology of micron-scaled through pores was formed within 100-μm inner diameter fused silica capillary. This pump utilizes electroosmotic flow to propel liquid solution with no moving parts. The Nafion® house design in the cathode chamber separates the electrolytic bubble interference from flow channels. The maximum flow rate and maximum pressure generated by the pump are 3.0 μL/min and 3.5 atm, respectively, at 6 kV. The flow rate can be controlled in the range 200 nL-3.0 μL/min by adjusting applied electric filed. As the monolith is silica-based, this pump can be used for a variety of fluids, especially for organic solvents such as acetonitrile and methanol, without swelling and shrinking problems. These results indicate that the pump can provide sufficient pressure and flow for micro-total-analysis systems (μTAS).
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Cheng, X., X. He, and Y. Zhang. "An Atomic Force Microscopic Investigation on Single Secondary Particle of Silica Aerogel Monolith." In MS&T19. TMS, 2019. http://dx.doi.org/10.7449/2019mst/2019/mst_2019_1343_1350.

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Cheng, X., X. He, and Y. Zhang. "An Atomic Force Microscopic Investigation on Single Secondary Particle of Silica Aerogel Monolith." In MS&T19. TMS, 2019. http://dx.doi.org/10.7449/2019/mst_2019_1343_1350.

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Karlina, Olga K., Galina A. Varlakova, Sergei A. Dmitriev, Michael I. Ojovan, Valery V. Poluektov, and Vladislav A. Petrov. "Thermochemical Conditioning of Radioactive Waste: Structure and Properties of Final Processed Product." In ASME 2003 9th International Conference on Radioactive Waste Management and Environmental Remediation. ASMEDC, 2003. http://dx.doi.org/10.1115/icem2003-4560.

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Thermochemical processing method is based on utilization of energy of chemical reactions between components of special exothermic mixtures (termed heat base) to melt radioactive waste and form a vitreous melt after cooling of which a durable monolith product is formed in which radionuclides are fixed. Compositions were studied, structure and properties of final products of thermochemical treatment of ash residue from incineration of solid radioactive waste, spent inorganic ion exchangers (e.g. clinoptililite and silica gel), contaminated clay and sand-based soils, Investigations showed that matrix material is dominantly amorphous and on compliesis to basic requirements to solidified radioactive wast of medium level of activity.
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Tonelli, M., S. Turrell, O. Cristini, H. El Hamzaoui, B. Capoen, M. Bouazaoui, C. Kinowski, M. Gazzano, and M. C. Cassani. "Direct laser-assisted synthesis of localized gold nanoparticles from both Au (III) and Au (I) precursors within a silica monolith." In SPIE Photonics Europe. SPIE, 2012. http://dx.doi.org/10.1117/12.922537.

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Bhatia, Tania, G. V. Srinivasan, Sonia V. Tulyani, Robert A. Barth, Venkat R. Vedula, and William K. Tredway. "Environmental Barrier Coatings for Monolithic Silicon Nitride: Bond Coat Development." In ASME Turbo Expo 2007: Power for Land, Sea, and Air. ASMEDC, 2007. http://dx.doi.org/10.1115/gt2007-27685.

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Environmental barrier coatings (EBCs) are being developed for silicon carbide (SiC) based composites and monolithic silicon nitride (Si3N4) to protect against the accelerated oxidation and subsequent silica volatilization in high temperature high-pressure steam environments encountered in gas turbine engines. It has been found that the application of EBCs developed for SiC-based composites (EBCSiC) to monolithic silicon nitride results in a loss of room temperature mechanical strength of the monolithic substrate. In this paper, we discuss the development of a bond coat system tailored for monolithic silicon nitride that helps retain the strength of the substrate. Some of the unique requirements and challenges associated with the processing of non-line-of-sight EBCs for Si3N4 will also be discussed. Preliminary results from coating of airfoils will be presented.
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Bhatia, Tania, Venkat Vedula, Harry Eaton, Ellen Sun, John Holowczak, and Gary Linsey. "Development and Evaluation of Environmental Barrier Coatings for Si-Based Ceramics." In ASME Turbo Expo 2004: Power for Land, Sea, and Air. ASMEDC, 2004. http://dx.doi.org/10.1115/gt2004-54092.

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Environmental barrier coatings (EBCs) are being developed for silicon carbide (SiC) based composites and monolithic silicon nitride (Si3N4) to protect against the accelerated oxidation and subsequent silica volatilization in high temperature, high-pressure steam environments encountered in gas turbine engines. While EBCs for silicon carbide (EBCSiC) have been demonstrated in combustor liner applications, efforts are ongoing in the development of EBC systems for silicon nitride (EBCSiN). The challenges of adapting EBCSiC to monolithic Si3N4 are discussed in this paper. Progress in the area of EBCSiN including development and performance during field tests and tests simulating engine conditions are reviewed.
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Tsuchizawa, Tai, Hidetaka Nishi, Rai Kou, Hiroshi Fukuda, Hiroyuki Shinojima, Yasuhiko Ishikawa, Kazumi Wada, and Koji Yamada. "Silicon-silica Monolithic Photonic Integration for Telecommunications Applications." In Integrated Photonics Research, Silicon and Nanophotonics. Washington, D.C.: OSA, 2012. http://dx.doi.org/10.1364/iprsn.2012.itu4b.2.

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Yamada, K., T. Tsuchizawa, H. Nishi, R. Kou, H. Shinojima, H. Fukuda, T. Hiraki, Y. Ishikawa, and K. Wada. "Silicon-silica monolithic photonic integration platform for telecommunications applications." In 2012 Opto-Electronics and Communications Conference (OECC). IEEE, 2012. http://dx.doi.org/10.1109/oecc.2012.6276384.

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Reports on the topic "Silica monolith"

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Grimmer, D. P. Monolithic amorphous silicon modules on continuous polymer substrate. Office of Scientific and Technical Information (OSTI), March 1992. http://dx.doi.org/10.2172/5784428.

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Carlson, D., R. Ayra, M. Bennett, J. Brewer, A. Catalano, R. D'Aiello, C. Dickson, et al. Research on high-efficiency, single-junction, monolithic, thin-film amorphous silicon solar cells. Office of Scientific and Technical Information (OSTI), September 1989. http://dx.doi.org/10.2172/5434340.

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Catalano, A., D. Carlson, R. Ayra, M. Bennett, R. D'Aiello, C. Dickson, C. Fortmann, et al. Research on high-efficiency, single-junction, monolithic, thin-film amorphous silicon solar cells. Office of Scientific and Technical Information (OSTI), October 1989. http://dx.doi.org/10.2172/5496057.

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Ayra, R., M. Bennett, C. Dickson, B. Fieselmann, C. Fortmann, B. Goldstein, J. Morris, et al. Research on high-efficiency, single-junction, monolithic, thin-film amorphous silicon solar cells. Office of Scientific and Technical Information (OSTI), October 1989. http://dx.doi.org/10.2172/5383673.

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Grimmer, D. P. Monolithic amorphous silicon modules on continuous polymer substrate. Final subcontract report, 9 January 1991--14 April 1991. Office of Scientific and Technical Information (OSTI), March 1992. http://dx.doi.org/10.2172/10131823.

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Jeffrey, F. Photovoltaic manufacturing technology monolithic amorphous silicon modules on continuous polymer substrates: Final technical report, July 5, 1995--December 31, 1999. Office of Scientific and Technical Information (OSTI), March 2000. http://dx.doi.org/10.2172/754636.

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Wiesmann, H., J. Dolan, G. Fricano, and V. Danginis. Research on high-efficiency, single-junction, monolithic, thin-film amorphous silicon solar cells: Annual subcontract report, May 1985 - Jul 1986. Office of Scientific and Technical Information (OSTI), February 1987. http://dx.doi.org/10.2172/6587080.

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Jeffrey, F. Photovoltaic manufacturing technology monolithic amorphous silicon modules on continuous polymer substrates. Annual technical progress report, 5 July 1995--4 June 1996. Office of Scientific and Technical Information (OSTI), February 1997. http://dx.doi.org/10.2172/453486.

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Delahoy, A. E., E. Eser, F. Kampas, and R. Lenskold. Research on high-efficiency, single-junction, monolithic, thin-film amorphous silicon solar cells: Final report, October 1, 1983--January 31, 1987. Office of Scientific and Technical Information (OSTI), March 1989. http://dx.doi.org/10.2172/6304136.

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Jeffrey, F. Photovoltaic manufacturing technology monolithic amorphous silicon modules on continuous polymer substrates. Annual technical progress report, July 5, 1996--December 31, 1997. Office of Scientific and Technical Information (OSTI), August 1998. http://dx.doi.org/10.2172/656874.

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