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Utilisation de produits non traditionnels pour le traitement des matériaux de terrassement : impact sur les propriétés géotechniques et bilan environnemental / Soil treatment with non-traditional additives : impact on geotechnical properties and environmental assessmentBlanck, Gaëtan 12 February 2013 (has links)
Répondre aux défis du développement durable exige la prise en considération des aspects économiques, sociétaux et environnementaux des projets. Dans le domaine des terrassements, les actions portent notamment sur l'optimisation de la valorisation des matériaux extraits grâce aux techniques de traitement des sols. Le projet s'est principalement porté sur les produits de traitement dérivant de la transformation de matières premières renouvelables : solutions « enzymatiques », lignosulfonates et solutions acides. Des données factuelles concernant les effets des traitements sur les caractéristiques hydromécaniques de quatre sols (un limon, un sol argileux et deux sables) ont été acquises mettant en évidence une augmentation de l'efficacité du compactage après traitement du limon au produit enzymatique et au lignosulfonate. La recherche des mécanismes d'action s'est fondée sur une étude de la microstructure par microscopie électronique à balayage et porosimétrie au mercure complétée par l'évaluation des effets d'un ajout de produits tensioactifs sur les propriétés des sols. L'objectif de l'étude dépasse cependant l'évaluation des modalités d'action des produits et vise également à prendre en compte les préoccupations environnementales. Ainsi, une étude d'analyse du cycle de vie a été menée pour chaque application ce qui a permis d'identifier les conditions optimales pour lesquelles les traitements combinent intérêts techniques et environnementaux. Ces conditions sont réunies lors du compactage des sols secs sous réserve que l'étape de production et de transport des produits ne soit pas excessivement pénalisante comme mis en évidence lors de l'étude de sensibilité / Sustainable development principles lead earthworks companies to use all natural materials and to reduce the environmental impact of their activities. In this context, the use of industrial organic products derived from the processing of renewable matter has been proposed. In this study, three non traditional products have been selected: an enzymatic solution, a lignosulfonate and an acid solution. In a first approach, hydromechanical properties of four treated soils (a silt, a clayey soil and two sands) were investigated. The experimental results showed interesting applications for the silt when its natural water content is low. Indeed, the compaction ability of the soil was increased after enzymatic and lignosulfonate treatments. Thus, savings of water and energy could be expected during the construction stage. To gain a better understanding of the mechanisms of the treatment products, the microstructure of treated soil were investigated with scanning electron microscopy, mercury injection porosity and was completed by the study of a surfactant addition in soils. The global aim of the study was beyond the characterization of mechanical behavior of treated soils, therefore, environmental balance was also estimated for the different applications defined in accordance to the experimental results. For enzymatic and lignosulfonate treatments, a comparison of the global environmental impact was done thanks to a life cycle assessment methodology. This approach showed that technical and environmental interest are associated for the compaction of dry soils when the production and transport steps have limited environmental impact as demonstrated in the sensitivity analysis
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Synthesis of silica-polymer hybrid particles via controlled radical polymerization in aqueous dispersed media / Synthèse de particules hybrides silice-polymère par polyméristaion radicalaire contrôlée en milieu aqueux disperséQiao, Xiaoguang 20 December 2013 (has links)
Des polymères à base de méthacrylate de poly(oxyde d'éthylène) (PEOMA) avec des chaînes pendantes PEO (Mn = 300 ou 950 g mol-1) ou des copolymères de PEOMA300 et d'acide méthacrylique (AMA) ont été synthétisés par polymérisation radicalaire contrôlée par les nitroxydes en utilisant une alkoxyamine (BlocBuilder®) comme amorceur en présence de SG1 et d'une faible quantité de styrène. Les copolymères à base de PEOMA300 et d'AMA sont thermo- et pH-sensibles. Les deux types de macroalkoxyamines ont été utilisés pour amorcer la copolymérisation en émulsion du méthacrylate de n-butyle et du styrène et former, par auto-assemblage induit par la polymérisation, des particules composées de copolymères à blocs amphiphiles, en absence ou présence de particules de silice. En absence de silice, des particules stabilisées de façon stérique ou électrostérique ont été formées. La polymérisation présente les caractéristiques d'une polymérisation contrôlée avec néanmoins la formation d'une faible proportion de chaînes mortes. L'effet du pH, de la force ionique et de la nature ou de la concentration des macroalkoxyamines sur la cinétique de polymérisation et la morphologie des particules a été étudié, et des sphères, des vésicules ou des nanofibres ont été obtenues. Les macroalkoxyamines à base de PEO s'adsorbent sur la silice via la formation de liaisons hydrogène entre les chaînes PEO et les groupes silanol. La synthèse de copolymères à blocs en surface de la silice a conduit à la formation de particules hybrides de différentes morphologies (bonhomme de neige, multipodes, framboise, coeur-écorce, têtard, mille pattes) liées à la taille de la silice, au pH et à la nature du macroamorceur / Water-soluble brush-type polymers composed of poly(ethylene)oxide methacrylate (PEOMA) units with PEO side groups of various chain lengths (Mn = 300 and 950 g mol-1) or of PEOMA300 with methacrylic acid (MAA) were synthesized by nitroxide-mediated polymerization using an alkoxyamine initiator (BlocBuilder®) and SG1 nitroxide in the presence of a low amount of styrene. The PEOMA300-MAA based copolymers showed a dual temperature/pH response. The two series of macroalkoxyamines were used in aqueous emulsion copolymerization of nbutyl methacrylate and styrene leading to the formation of particles composed of amphiphilic block copolymers through polymerization-induced self-assembly, in both the absence and presence of silica. The experiments performed in the absence of silica particles resulted in the formation of sterically or electrosterically stabilized latexes. The polymerization exhibited all the features of a controlled system with however the presence of a small proportion of dead chains. The effect of pH value, ionic strength and type and concentration of the macroalkoxyamine initiator on polymerization kinetics and latex morphologies was investigated. Depending on the reaction conditions, spherical particles, vesicles or nanofibers were successfully prepared. The PEO-based macroalkoxyamines were shown to adsorb on the silica surface via hydrogen bond interaction between PEO and the silanol groups. This enabled block copolymers to be generated in situ on the silica surface leading to hybrid particles with snowman, raspberry, daisy, core-shell, “tadpole-” and “centipede-” like morphologies depending on the silica particle size, pH value and type of macroinitiator
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New micro and mesoporous materials for the reaction of methanol to olefinsLi, Zhibin 17 November 2014 (has links)
(1) We will show that nano sized samples of SAPO-34 synthesized by microwave heating presents much higher lifetime than standard-SAPO-34 synthesized by conventional hydrothermal method for the reaction of methanol to olefins.
(2) We will stabilize the Nano SAPO-34 in the ways such as steaming with water or calcinated in H2 condition.
(3) The treatment of mix alkali treatment with proper TPAOH/NaOH could make composites with mesopore and microporous structure in the zeolite ZSM-5 to reduce strong acid quantity and the change the selectivity of the main product.
(4) Different 8MR zeolite show different selectivity and lifetime in the same condition in the reaction of methanol to olefins. / Li, Z. (2014). New micro and mesoporous materials for the reaction of methanol to olefins [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/44229 / TESIS
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La Estampa Líquida. El Tensioactivo como Medio de Expresión Artístico / La Stampa Liquida. Il Tensioattivo come Mezzo di Espressione ArtisticaSimarro Escobar, Antonio 16 October 2020 (has links)
[ES] La presente tesis doctoral lleva por título La estampa líquida. El tensioactivo como medio de expresión artístico. Reúne la investigación de diversos artistas, cuyas obras surgen a partir de las posibilidades creativas de un químico tensor. Son el reflejo de nuevas estrategias y de la incorporación de nuevos materiales como medio creativo contemporáneo, y que tomamos como referentes para la invención de un nuevo método de entintado calcográfico.
Esta indagación toma como punto de partida los conceptos de tiempo y espacio, dos términos inherentes y complementarios, consecuencia directa del rastro y la huella derivada de una realidad social. La Modernidad líquida, categoría que define este estado actual y figura de cambio constante y de interinidad, acuñada por el sociólogo Zygmunt Bauman, nos sirve como metáfora para la interpretación de estos nuevos recursos. Del mismo modo, este ensayo recoge un análisis del diálogo permanente entre aquellos detalles cotidianos y desapercibidos, receptáculos contenedores de un devenir en forma de esfera, representación que adoptamos del filósofo Peter Sloterdijk.
Realizamos también, una aproximación a lo que fue una revolución en las vanguardias en el mundo de la gráfica: La técnica de la simultaneidad del color, inventada por el artista británico Stanley William Hayter y proceso primigenio del que surge esta tesis. Asimismo, se examinan aquellas técnicas de creación pictóricas, afines a nuestro estudio experimental, de las cuales nos imbuimos directamente.
Como resultado del estudio del efecto de transitoriedad tensioactiva, esta tesis propicia nuestra producción artística personal: Recuerdo del trayecto, que ilustra dicha evolución química a través del tiempo inmortalizado en forma de estampa. / [CA] La present tesi doctoral porta per títol L'estampa líquida. El tensioactiu com a mitjà d'expressió artístic. Reunix la investigació de diversos artistes, les obres dels quals sorgixen a partir de les possibilitats creatives d'un químic tensor. Són el reflex de noves estratègies i de la incorporació de nous materials com a mitjà d'expressió artístic contemporani, i que prenem com a referents per a la invenció d'un nou mitjà d'entintat calcogràfic. Aquesta indagació pren com a punt d'eixida els conceptes de temps i espai, dos termes inherents i complementaris, conseqüència directa del rastre i la petjada derivada d'una realitat social. La Modernitat líquida, categoria que defineix aquest estat actual i figura de canvi constant i de interinitat, encunyada pel sociòleg Zygmunt Bauman, ens servix com a metàfora per a la interpretació d'aquests nous recursos. De la mateixa manera, aquest assaig recull una anàlisi del diàleg permanent entre aquells detalls quotidians i desapercebuts, receptacles contenidors d'un esdevenir en forma d'esfera, representació que adoptem del filòsof Peter Sloterdijk. Realitzem també una aproximació al que va ser una revolució a les Avantguardes en el món de la gràfica: La tècnica de la simultaneitat del color, inventada per l'artista britànic Stanley William Hayter i procés primigeni del que sorgeix aquesta tesi. Així mateix, s'examinen aquelles tècniques de creació pictòriques, afins al nostre estudi experimental, de les quals ens inbuïm directament. Com a resultat de l'estudi de l'efecte de transitorietat tensioactiva, aquesta tesi propicia la nostra producció artística personal: Recuerdo del trayecto, que il·lustra l'esmentada evolució química a través del temps immortalitzat en forma d'estampa. / [IT] La presente tesi di dottorato si intitola La stampa liquida. Il tensioattivo come mezzo di espressione artistica. Nel nostro lavoro intendiamo riunire le ricerche di vari artisti, le cui opere nascono dalle possibilità creative di un tensore chimico. Esse riflettono le nuove strategie e l'incorporazione di nuovi materiali come mezzo creativo contemporaneo, che prendiamo come riferimento per l'invenzione di un nuovo metodo per inchiostrare la matrice calcografica.
Questa indagine prende come punto di partenza i concetti di tempo e spazio, due termini intrinseci e complementari, conseguenze dirette e prodotti derivanti da una determinata realtà sociale. La Modernità Liquida, categoria riferita allo status quo della società contemporanea, che rappresenta in costante cambiamento e una condizione ad interim, coniata dal sociologo Zygmunt Bauman, serve come metafora per l'interpretazione di queste nuove risorse. Allo stesso modo, questo saggio cattura un'analisi del dialogo permanente tra quei dettagli quotidiani e inosservati, i contenitori di un divenire in forma di sfera, così come apprendiamo dal filosofo Peter Sloterdijk.
Abbiamo anche operato un'approssimazione a quella che è stata una rivoluzione nel mondo della grafica: la tecnica della concorrenza del colore, la cui partenità si ascrive all'artista britannico Stanley William Hayter, primo processo da cui nasce questa tesi. Inoltre, il nostro alvoro esamina anche quelle tecniche di creazione pittorica, simili al nostro studio sperimentale e di cui il nostro lavoro è fortemente impregnato.
Come risultato dello studio dell'effetto della transitorietà surfattante, questa tesi promuove la nostra personale produzione artistica, Recuerdo del trayecto, che illustra questa evoluzione chimica attraverso il tempo immortalato sotto forma di stampa. / [EN] This doctoral thesis is named La estampa líquida. El tensioactivo como medio de expresión artístico (The Liquid Print. Surfactant as a resource of artistic expression). It gathers the investigation of different artists whose works arise from the creative possibilities of a tensor chemical. They are the reflection of new strategies and of the incorporation of new materials as a contemporary creative resource, and they are considered an example for the invention of a new chalcographic inking method.
This investigation takes the concepts of time and space as a starting point. These concepts are inherent and complementary, a direct consequence of the trace and the print that stem from a social reality. The Liquid Modernity, a category which defines this current state and a symbol of constant change and temporariness, coined by sociologist Zygmunt Bauman, acts as a metaphor for the interpretation of these new resources. Likewise, this essay gathers an analysis of the permanent dialogue between those daily and unnoticed details, containing receptacles of a spherical future, a representation adopted from philosopher Peter Sloterdijk.
We also carry out an approximation to what was a revolution in Avant-garde in the world of graphic arts: the technique of viscosity printing, invented by British artist Stanley William Hayter, an original process from which this thesis stems. Additionally, we examine those pictorial techniques of creation, related to our experimental study and from which we are directly influenced.
As a result of the study of the effect of surfactant transience, this thesis fosters our personal artistic production: Recuerdo del trayecto, which illustrates this chemical evolution through the time immortalized in the shape of a print. / Simarro Escobar, A. (2020). La Estampa Líquida. El Tensioactivo como Medio de Expresión Artístico [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/152187 / TESIS
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Studium interakcí tenzidové složky přípravku Septonex s vybranými proteiny / Study of interactions of the surfactant component of Septonex with selected proteinsBohunská, Miroslava January 2021 (has links)
The study of protein and surfactant interactions is of great significance in a number of applications, such as the cosmetic, food or pharmaceutical industries and many others. However, they require further study due to their compositional complexity and the limitations of current analytical approaches. In this thesis, the cationic surfactant septonex in combination with two differently charged proteins lysozyme and bovine serum albumin under different physiological conditions (temperature, surfactant concentration, environment and others) was selected to study the interactions. Characterization of protein-surfactant interactions is a very important but challenging task, therefore it is essential to use appropriate approaches to explore the nature of these interactions. In order to unify the information to provide rational models, calorimetric methods (DSC, ITC) and dynamic light scattering were used. Isothermal titration calorimetry monitors the evidence for the formation of the system of the mentioned substances and information on aggregation behavior, differential scanning calorimetry characterizes the thermal stability of proteins and dynamic light scattering made it possible to monitor changes in particle size. Both proteins have been proven to interact with positive septonex, even if the lysozyme molecule is also positively charged. However, significant differences were found between the two proteins. From the obtained results it is evident that the identical charge of the protein with the surfactant has an effect on the intensity of the measurement, although all measured interactions showed an endothermic character.
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Vliv iontů manganu ve struktuře hydroxidu nikelnatého na vlastnosti elektrod / Influence of Mn ionts in nickel hydroxide on behavour electrodesCirkovský, Jaroslav January 2010 (has links)
The aim of my diploma thesis was to explore the influence of manganese ions put into nickel nitrate structure. The attention was focused mainly on the stabilization of nickel nitrate a modification, which could not change into b modification. The theoretical part of my thesis focused on applied materials, kinds of acumulators, basic parameters of acumulators and the description of chosen methods of measurement employed. It contained the electrodeposition, the impedance spectroscopy and the cyclic voltammetry. The task of the experimental part was to measure the effect of manganese ions put into potassium hydroxide structure. Proportions of Ni (nickel nitrate) : Mn (manganese nitrate) 10:0, 7:3, 5:5, 6:1 and 6:4 were blended for the measurement. By means of the electrodeposition, there was a thin layer of nickel hydroxide with an admixture of manganese ions from nickel nitrate and manganese nitrate dilution put on the nickel plate. After the spread of the thin layer on the nickel plate, the measurement by the method of cyclic voltammetry followed. The next task consisted in trying to add KOH (potassium hydroxide) anionic and cationic surfactant into the dilution.
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Charakterizace hyaluronanu a jeho interakcí s tenzidy ultrazvukovou spektroskopií a densitometrií / Ultrasonic and Densitometric Characterization of Hyaluronan and its Interaction with SurfactantHurčíková, Andrea January 2014 (has links)
This disertation thesis is focused on the study of physico-chemical interactions of hyaluronan (with molecular weights from 10 to 1750 kDa) with cationic surfactants measured using uncommon technique named high resolution ultrasonic spectroscopy. Densitometer was also used for the study of these interactions, in measuring of density and ultrasonic velocity of hyaluronan with different molecular weight in dependence on elevated temperature (25 50 °C). The aim is the determination of critical micelle concentration (CMC) and critical aggregation concentration (CAC) of the suractants in the absence and in the presence of hyaluronan with various molecular weights. Interactions in this system are important for the design of the systems for the targeted delivery, especially for the drugs. The experiments were made in water and sodium chloride solution. The significant breakpoint in the ultrasonic velocity showed changes in the system hyaluronan-surfactant.
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Interfacial Tension and Phase Behavior of Oil/Aqueous Systems with Applications to Enhanced Oil RecoveryJaeyub Chung (9511022) 16 December 2020 (has links)
Chemical enhanced oil recovery (cEOR) aims to increase the oil recovery of mature oil fields, using aqueous solutions of surfactants and polymers, to mobilize trapped oil and maintain production. The interfacial tensions (IFTs) between the injected aqueous solution, the oil droplets in reservoirs, and other possible phases formed (e.g., a “middle phase” microemulsion) are important for designing and assessing a chemical formulation. Ultralow IFTs, less than 10<sup>-2</sup> mN·m<sup>-1</sup>, are needed to increase the capillary number and help mobilize trapped oil droplets. Despite this fact, phase behavior tests have received more attention than IFTs for designing and evaluating surfactant formulations that result in high oil recovery efficiencies, because incorporating reliable IFTs into such evaluation process is avoided due to difficulties in obtaining reliable values. Hence, the main thrusts of this dissertation are to: (a) develop robust IFT measurement protocols for obtaining reliable IFTs regardless of the complexity of water and oil phase constituents and (b) improve the existing surfactant polymer formulation evaluation and screening processes by successfully incorporating the IFT as one of the critical parameters.<br>First, two robust tensiometry protocols using the known emerging bubble method (EBM) and the spinning bubble method (SBM) were demonstrated, for determining accurately equilibrium surface tensions (ESTs) and equilibrium IFTs (EIFTs). The protocols are used for measuring the dynamic surface tensions (DSTs), determining the steady state values, and establishing the stability of the steady state values by applying small surface area perturbations by monitoring the ST or IFT relaxation behavior. The perturbations were applied by abruptly expanding or compressing surface areas by changing the bubble sizes with an automated dispenser for the EBM, and by altering the rotation frequency of the spinning tube for the SBM. Such robust tension measurement protocols were applied for Triton X-100 aqueous solutions at a fixed concentration above its critical micelle concentration (CMC). The EST value of the model solution was 31.5 ± 0.1 mN·m<sup>-1</sup> with the EBM and 30.8 ± 0.2 mN·m<sup>-1</sup> with the SBM. These protocols provide robust criteria for establishing the EST values.<br>Second, the EIFTs of a commercial single chain anionic surfactant solution in a synthetic brine against a crude oil from an active reservoir were determined with the new protocol described earlier. The commercial surfactant used here has an oligopropoxy group between a hydrophobic chain and a sulfate head group. The synthetic brine has 9,700 ppm of total dissolved salts, which are a mixture of sodium chloride (NaCl), potassium chloride (KCl), manganese (II) chloride tetrahydrate (MnCl<sub>2</sub>·4H<sub>2</sub>O), magnesium (II) chloride hexahydrate (MgCl<sub>2</sub>·6H<sub>2</sub>O), barium chloride dihydrate (BaCl<sub>2</sub>·2H<sub>2</sub>O), sodium sulfate decahydrate (Na<sub>2</sub>SO<sub>4</sub>·10H<sub>2</sub>O), sodium bicarbonate (NaHCO<sub>3</sub>), and calcium chloride dihydrate (CaCl<sub>2</sub>·2H<sub>2</sub>O). The DSTs curves of the surfactant concentrations from 0.1 ppm to 10,000 ppm by weight had a simple adsorption/desorption equilibrium at air/water surface with surfactant diffusion from bulk aqueous phase. Such a mechanism was also observed from the tension relaxation behavior after area perturbations for the oil/water interfaces while DIFT measurements. The CMC of the commercial surfactant was determined to be 12 ppm in water and 1 ppm in the synthetic brine used. From the initial tension reduction curves from DST and DIFT measurements, the equilibrium timescales were shorter with brine than with water, because the adsorbed surfactant on the oil/water interfaces were partitioned into oil phases. For both DST and DIFT results suggest that the adsorbed surfactant layer at interfaces were typical adsorbed soluble monolayers.<br>Third, the phase and rheological behavior of a commercial anionic surfactant in water and in brine are important for large scale applications. A phase map of the surfactant at 25 °C at full range of surfactant concentration was obtained. The supramolecular structures of the various phases were characterized by dynamic light scattering (DLS), cryogenic transmission electron microscopy (cryo-TEM), conductimetry, densitometry, and x-ray scattering. The identified phases evolved as the surfactant concentration was increased; they were a micellar solution phase, a hexagonal liquid crystalline phase, and a lamellar liquid crystalline phase. In addition, the characterization results provided detailed information about supramolecular structure parameters such as micellar sizes and their aggregation numbers, and liquid crystal spacings. The phase and rheological behavior trends identified here were of great importance because the trend was similar to that of single chain monoisomeric surfactant. Thus, this study provides a potential universality of phase behavior trends of surfactant-water systems despite of the multicomponent nature of surfactants.<br>Fourth, the EIFTs of the pre-equilibrated mixtures of surfactant, brine, and oil were determined and compared to the EIFTs prior to pre-equilibration, in order to systematically identify the most relevant IFT for oil recovery. The EIFT between surfactant solutions and oil without any pre-equilibration prior to tension measurements is defined as the un-pre-equilibrated EIFT (EIFT<sub>up</sub>). The EIFT between oil and water phases after the pre-equilibration of surfactant, brine, and oil is defined as pre-equilibrated EIFT (EIFT<sub>p</sub>). The EIFT<sub>p</sub>’s were generally higher than EIFT<sub>up</sub>’s. In addition, the effects of three mixing methods and the water-to-oil volume ratio (WOR) on the EIFT<sub>p</sub> were evaluated. Out of three mixing methods, (A) mild mixing, (B) magnetic stirring, and (C) shaking vigorously by hand, method C produced mixtures which are the closest to the equilibrium state. The mixtures produced by method C had the largest decrease of the surfactant concentration during pre-equilibration due to the surfactant partitioning into oil phases. Moreover, the WOR affects the EIFT<sub>p</sub> significantly due to the preferential partitioning of surfactant components into oil phases. More specifically, the WOR and the EIFT<sub>p</sub> were found to be inversely correlated, because the amount of partitioned surfactant increased as the oil volume fraction increased. The EIFT<sub>p</sub>’s were different from the EIFT<sub>up</sub>’s at the same total surfactant concentrations in the aqueous layer evidently because of preferential partitioning of the various surfactant components.<br>Finally, the effect of surfactant losses due to adsorption into the rock surface on the pre-equilibrated EIFT (EIFT<sub>p</sub>) were evaluated to improve surfactant formulation protocols. Here, five types of EIFTs were identified, along with robust protocols for determining them. These are: (I) the un-pre-equilibrated equilibrium IFT (EIFT<sub>up</sub>); (II) the un-pre-equilibrated EIFTs in the presence of rock (EIFT<sub>up,rock</sub>); (III) the pre-equilibrated EIFTs (EIFT<sub>p</sub>) in the presence of oil; (IV) the pre-equilibrated EIFT in the presence of rock and oil (EIFT<sub>p,rock</sub>); and (V) the effluent EIFT (EIFT<sub>eff</sub>). The EIFT<sub>up</sub> is the EIFT of the aqueous surfactant/brine solution against an oil drop without any pre-equilibration. The EIFT<sub>up,rock</sub> is the EIFT between an oil drop and the surfactant solution after pre-equilibration with a rock sample to account for adsorption losses. The EIFT<sub>p</sub> is the EIFT between the pre-equilibrated water and the oil phases from surfactant/brine/oil mixtures. The EIFT<sub>p,rock</sub> is the EIFT between the pre-equilibrated water and the oil phases from surfactant/brine/oil/rock mixtures. The EIFT<sub>eff</sub> is the EIFT from an effluent sample mixture of a laboratory-scale core flood test. Among the five types of EIFTs, the EIFT<sub>p,rock</sub> was found to be the most important for the highest oil recovery performance in core flood tests, because it captures the most important surfactant partition processes, the partitioning to the oil phase and the partitioning by adsorption on the rock surface. Among three surfactant formulations tested with core flood experiments, the one with the lowest EIFT<sub>p,rock</sub> (~0.01 mN·m<sup>-1</sup>) had the highest oil recovery ratio (78%), and the one with the highest EIFT<sub>p,rock</sub> (~0.2 mN·m<sup>-1</sup>) had the lowest oil recovery ratio (55%). The other EIFTs correlated less with the oil recovery performance. Identifying surfactant formulations that have low or ultralow EIFTs, especially ultralow EIFT<sub>p,rock</sub>’s, are critical for screening formulations appropriate for core flood tests and target field applications, and for predicting oil recovery performance. These works are a significant contribution for improving (a) the surfactant formulation evaluation protocols, and (b) the utilization of reliable IFTs and phase behavior test protocols for oil recovery and many other surfactant and colloid sciences applications.<br>
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Ionene and ionene alkyl sulfate stoichiometric complexes: Temperature and humidity sensitive materialsYu, Quanwei 28 October 2004 (has links)
Stoichiometric polyelectrolyte-surfactant complexes represent a type of comb-shaped polymers, in which every polymer chain unit has an electrostatically bound &quot;side chain&quot;. These complexes are water-insoluble. In the solid state they assemble spontaneously into mesogenic structures. The [X,Y]-ionenes ([(CH2)XN+(CH3)2(CH2)YN+(CH3)2]nBr-2n) investigated formed stoichiometric complexes with alkyl sulfates. The ionene alkyl sulfate complexes display mesogenicity, i.e. optically isotropic dry complexes underwent lyotropic and thermotropic phase transitions to the optically anisotropic phase (and vice versa) under controlled relative humidity. The optically anisotropic phases exhibited hexagonal textures as revealed by polarizing microscopy. A new feature is the lyotropic transition brought about by the uptake of water through the gas phase. The complexes were all sensitive to both humidity and temperature. In principle, the effects can be applied to measure humidity.
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Nichtionische polyethoxylierte Tenside in methansulfonsauren Zinn- und Zinn-Silber-ElektrolytenWehner, Susanne 28 November 2005 (has links)
The investigations are related to the influence of nonionic polyethoxylated surfactant on Tin- and Tin-Silver depositions. Cyclovoltammetry, electrochemical depositions in Hull cell, with quartz crystal microbalance, impedance spectroscopy, X-ray diffraction, REM and others were used as methods of characterization. / Die Untersuchungen befasssen sich mit dem Einfluss von nichtionischen polyethoxylierten Tenside auf die Zinn- und Zinn-Silber-Abscheidung, die durch Zyklovoltammetrie, Abscheidungen in der Hullzelle, mit der elektrochemischen Quarzmikrowaage, der Impedanzspektroskopie, Röntgendiffraktometrie, Rasterelektronenmikroskopie und Tensiometrie charakterisiert wurden.
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