Добірка наукової літератури з теми "Colloids"

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Статті в журналах з теми "Colloids"

1

Natarajan, N., and G. Suresh Kumar. "Numerical modelling of colloidal transport in fractured porous media with double layered fracture-skin." Journal of Geo-Engineering Sciences 1, no. 2 (2014): 83–94. http://dx.doi.org/10.3233/jgs-130016.

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A numerical model is developed for studying the transport of colloids in a coupled fracture-matrix system with double layer fracture-skin. The governing equations describing colloid transport along the fracture and diffusion into fracture-skin layers as well as rock-matrix, normal to the fracture axis are coupled with each other. The coupled non linear equations are solved numerically with fully implicit finite difference method. Sensitivity analysis is performed to investigate the effect of various colloid properties on the colloid concentration in the multiple porosity fractured system. Colloid remobilisation and filtration has been accounted in the model. Results suggest that the inclusion of a second fracture-skin layer has a marginal effect on the transport mechanism of colloids. As colloid velocity increases, the diffusion of colloids into the fracture-skin decreases due to the low residence time available for the colloids. High first layer fracture-skin thickness and porosity enhances the diffusion of colloids from the aqueous phase of the fracture into the skin considerably resulting in low colloidal concentration within the fracture. Variation in the porosity as well as thickness of the second layer of the fracture-skin has negligible effect on the colloidal concentration in the fracture. The colloid transport mechanism in fractured porous media is marginally affected by the multiple porosity system, or in other words additional layers of fracture skin. High filtration coefficient and low remobilisation coefficient result in low colloidal concentration within the fracture.
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2

Bagalkot, Nikhil, and G. Kumar. "Colloid Transport in a Single Fracture–Matrix System: Gravity Effects, Influence of Colloid Size and Density." Water 10, no. 11 (October 27, 2018): 1531. http://dx.doi.org/10.3390/w10111531.

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A numerical model was developed to investigate the influence of gravitational force on the transport of colloids in a single horizontal fracture–matrix system. Along with major transport phenomena, prominence was given to study the mass flux at the fracture–matrix interface, and colloid penetration within the rock matrix. Results suggest that the gravitational force significantly alters and controls the velocity of colloids in the fracture. Further, it was shown that the colloid density and size play a vital part in determining the extent that gravity may influence the transport of colloids in both fracture and rock matrix. The mass flux transfer across the fracture–matrix interface is predominantly dependent on the colloidal size. As large as 80% reduction in penetration of colloids in the rock matrix was observed when the size of the colloid was increased from 50–600 nm. Similarly, the farther the density of colloid from that of the fluid in the fracture (water), then the higher the mitigation of colloids in the fracture and the rock matrix. Finally, a non-dimensional parameter “Rock Saturation Factor” has been presented in the present study, which can offer a straightforward approach for evaluating the extent of penetration of colloids within the rock matrix.
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3

Klitzke, Sondra, Friederike Lang, Jason Kirby, Enzo Lombi, and Rebecca Hamon. "Lead, antimony and arsenic in dissolved and colloidal fractions from an amended shooting-range soil as characterised by multi-stage tangential ultrafiltration and centrifugation." Environmental Chemistry 9, no. 5 (2012): 462. http://dx.doi.org/10.1071/en12010.

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Environmental context The size of soil colloids is – among other characteristics – crucial for the mobility of associated contaminants. We analysed the effect of liming on the size of colloids mobilised from strongly contaminated shooting-range soils using multi-stage tangential ultrafiltration (MTUF) for the size fractionation of dispersed soil colloids. Our results indicate the high analytical potential of MTUF and show that liming induces the aggregation of colloids, thereby decreasing the mobilisation of colloid-bound Sb and As, but increasing colloidal Pb. Abstract The size and composition of colloids are important factors controlling their relevance as carriers of metal(loid)s in soils. Liming, which is often used to reduce the effect of heavy metal contamination in soil, can alter concentrations and characteristics of colloids in soil suspension. In batch studies, we compared the influence of changing pH and cation valency on the size distribution and composition of dispersed colloids and on the concentrations of Pb, As and Sb associated with colloids and in solution following the addition of Ca(OH)2 and KOH to soil samples from a contaminated-shooting range site. Multi-stage tangential ultrafiltration (MTUF) and centrifugation were used for the size fractionation of colloids in aqueous suspension. An increase in soil pH resulted in an increase in colloid-associated Pb, with much higher concentrations in the KOH than in the Ca(OH)2 treated samples. In contrast colloid-associated Sb and As increased only in the KOH treated samples. Addition of the monovalent K-ion induced the dispersion of small (~9–220 nm) organo(-mineral) colloids, whereas the divalent Ca-ion suppressed their dispersion and led to the formation of larger colloids (220–1200 nm). Whereas centrifugation underestimated contaminants (i.e. Pb) associated with organic colloids (density <2.6 g cm–3) MTUF gave a distorted distribution of inorganic colloids (i.e. needle-shaped sesquioxides).
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4

Ibrahim, Yahaya, and Saratu Abddulfatah. "PAIR INTERACTION OF ACTIVE COLLOIDS IN AN EXTERNAL CHEMICAL GRADIENT." FUDMA JOURNAL OF SCIENCES 6, no. 3 (July 6, 2022): 271–77. http://dx.doi.org/10.33003/fjs-2022-0603-999.

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We study the pair interaction of chemically isotropic active colloidal particles in an externally imposed chemical gradient. Colloid particles migrate in response to a gradient of chemical solutes (i.e., via the diffusiophoresis mechanism). The particles motion induces fluid flow and distort locally the background chemical concentration field. Using the methods of images, we calculate the phoretic inter-particle interaction between two symmetric active colloids in the presence of an externally applied gradient. We highlight an interesting colloidal dipole that would arise from tuning the surface and chemical activity of the colloids. The colloidal phoretic dipoles share similar properties to the electrostatic dipoles. The inter-particle interaction we obtained is an important component for a large-scale simulation of the active colloid suspension. It may also help towards better understanding of the active systems’ emergent phenomena
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5

Schmid, Günter, Andreas Lehnert, Ulrich Kreibig, Zbignew Adamczyk, and Peter Belouschek. "Synthese und elektronenmikroskopische Untersuchung kontrolliert gewachsener, ligandstabilisierter Goldkolloide sowie theoretische Überlegungen zur Oberflächenbelegung durch Kolloide / Synthesis and Electron Microscopic Investigation of Controlled Grown, Ligand Stabilized Gold Colloids and Theoretical Considerations on the Covering of Surfaces by Colloids." Zeitschrift für Naturforschung B 45, no. 7 (July 1, 1990): 989–94. http://dx.doi.org/10.1515/znb-1990-0713.

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18 nm Gold colloids are used as seeds for a controlled growth of 36 nm colloids which are then stabilized by P(m-C6H4SO3Na)3. These colloids can be isolated as golden leaflets and are readily soluble in water in virtually any concentration. Electron microscopic investigations prove a very small particle size distribution. X-ray powder diffraction and molecular weight determinations support the results of the electron microscopic investigations. The distance between the colloidal particles in two-dimensional layers corresponds to double-layers of phosphane ligands around each colloid, twice 1.2 nm. Isolated colloids seem to possess thicker ligand shells. A single 44 nm colloid shows a corona of about 7.2 nm thickness, corresponding to 12 phosphane layers. A quantitative description of two-dimensional packing densities is suggested using a novel theoretical model. By means of Monte Carlo simulations the two-dimensional structures are formed during the covering of supports of different geometry can be calculated.
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6

Niu, Lihua, Rui Chen, Yi Li, Yamei Chen, Wenlong Zhang, Huanjun Zhang, and Longfei Wang. "Colloidal Filterable Bacteria Enhance Ammonia Nitrogen Enrichment in River Colloids under Different Turbidity Conditions: Bacterial Diversity, Assembly Mechanism, and Nitrogen Transformation." Water 16, no. 7 (April 1, 2024): 1024. http://dx.doi.org/10.3390/w16071024.

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Turbidity has been one of the most typical problems in urban rivers, accompanied by eutrophication. Though the colloid is a nonnegligible factor associated with turbidity and nutrient enrichment in urban rivers, the characteristics of nitrogen enrichment and bacterial communities of colloids under different turbidity conditions of urban rivers have not been well understood. In this study, colloids of low and high molecular weights (LMW, 30 kDa–0.2 μm, and HMW, 0.2–1 μm) were separately collected from the bulk water (<1 μm) of several typical urban rivers in China. Since the colloidal concentration presented the significantly highest correlation with turbidity, colloidal characteristics were further explored under three turbidity gradients with two cutoffs of 10 and 30 NTU. Results showed that colloidal organic matter in medium and high turbidity rivers was mainly sourced from the release of endogenous plankton and the proportion of colloidal organic carbon in dissolved organic carbon increased from 33% to 38% with increased turbidity. Colloidal ammonia nitrogen in medium turbidity accounted for the highest proportion (an average of 60%) in bulk water, which could be explained by the significantly positive correlation of colloidal ester groups and ammonia nitrogen (R2 = 0.47). Bulk water, HMW, and LMW colloids presented different dominant bacterial genera and LMW colloids also contained three unique dominant filterable genera: Flavobacterium, Acinetobacter, and Limnohabitans. LMW colloidal filterable bacteria under medium and high turbidities presented the greatest potential for dissimilatory nitrate reduction to ammonium, which might further enhance the enrichment of ammonia nitrogen in colloids. This study provides a primary understanding of the characteristics of colloids and colloidal bacterial communities in urban rivers from the perspective of turbidity and puts a new insight on the remediation of rivers under medium turbidity.
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7

Nikishina, Maria B., Evgenia V. Ivanova, Yury M. Atroschenko, Irina V. Shahkeldyan, Igor V. Blohin, Loik G. Mukhtorov, Konstantin I. Kobrakov, and Georgy V. Pestsov. "Biological activity of colloidal solutions of silver, obtained by means of sálix cáprea extract." Butlerov Communications 60, no. 10 (October 31, 2019): 54–59. http://dx.doi.org/10.37952/roi-jbc-01/19-60-10-54.

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The presented publication is devoted to the study of the biological activity of silver colloids synthesized based on extracts obtained from various parts of the goat willow plant (Sálix cáprea). The ability of colloidal silver solutions of various concentrations to stimulate growth processes in wheat seeds at the germination stage is analyzed. The effect of colloidal solutions on the catalytic effect of amylase was studied. The fungicidal activity of synthesized silver particles was studied. For the study, colloidal silver particles were obtained by the "green synthesis" method. Extracts of goat willow bark, leaves and buds of varying degrees of dilution were used as a reducing agent. The analysis of sugar content and pH of solutions of plant extracts before and after colloid formation was carried out in order to establish the participation of sugars and acids in the process of silver recovery. The biological activity of colloids was analyzed on the seeds of winter wheat cultivar "Moskovskaya-39". The germination energy of wheat seeds was determined on the 3rd day after sowing by counting the germinated seeds. Amylase activity was measured in the roots and shoots of wheat plants by the amount of undecomposed starch by spectrophotometry. Fungicidal activity was studied with respect to fungi: F. moniliforme, F. oxysporum, S. sclerotiorum, V. inaequalis, R. solani, B. sorokiniana, P. ostreatus. The data obtained show that the sugars that make up the initial extracts of various parts of goat willow are completely consumed in the process of silver recovery and the formation of colloidal particles. A change in the acid content at the stage of colloid formation does not allow us to draw an unambiguous conclusion about the mechanism of participation of these compounds in the process of colloid formation. A study of the biological activity of synthesized silver colloids showed their high ability to stimulate growth processes in wheat seeds. A study of enzymatic catalysis also shows, in general, the positive effect of silver colloids on amylase activity within 1 minute of the starch hydrolysis reaction. An analysis of the data obtained in the study of fungistaticity suggests that silver colloids obtained in extracts from leaves, bark and willow inflorescences exhibit high fungicidal activity against F. moniliforme, S. sclerotiorum, P. ostreatus and B. sorokiniana.
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8

Joshi, Darshana, Dylan Bargteil, Alessio Caciagli, Jerome Burelbach, Zhongyang Xing, André S. Nunes, Diogo E. P. Pinto, Nuno A. M. Araújo, Jasna Brujic, and Erika Eiser. "Kinetic control of the coverage of oil droplets by DNA-functionalized colloids." Science Advances 2, no. 8 (August 2016): e1600881. http://dx.doi.org/10.1126/sciadv.1600881.

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We report a study of reversible adsorption of DNA-coated colloids on complementary functionalized oil droplets. We show that it is possible to control the surface coverage of oil droplets using colloidal particles by exploiting the fact that, during slow adsorption, compositional arrest takes place well before structural arrest occurs. As a consequence, we can prepare colloid-coated oil droplets with a “frozen” degree of loading but with fully ergodic colloidal dynamics on the droplets. We illustrate the equilibrium nature of the adsorbed colloidal phase by exploring the quasi–two-dimensional phase behavior of the adsorbed colloids under the influence of depletion interactions and present simulations of a simple model that illustrates the nature of the compositional arrest and the structural ergodicity.
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9

Lattuada, Marco, and Kata Dorbic. "Polymer Colloids: Moving beyond Spherical Particles." CHIMIA 76, no. 10 (October 26, 2022): 841. http://dx.doi.org/10.2533/chimia.2022.841.

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When thinking about colloidal particles, the fist image that comes into mind is that of tiny little polystyrene spheres with a narrow size distribution. While spherical polymer colloids are one of the workhorses of colloid science, scientists have been working on the development of progressively advanced strategies to move beyond particles with spherical shapes, and prepared polymer colloids with more complex morphologies. This short review aims at providing a summary of these developments, focusing primarily on methods applicable to submicron particles, with an eye towards their applications and some discussion about advantages and drawbacks of the various approaches.
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10

Laabs, C., G. Amy, and M. Jekel. "Organic colloids and their influence on low-pressure membrane filtration." Water Science and Technology 50, no. 12 (December 1, 2004): 311–16. http://dx.doi.org/10.2166/wst.2004.0728.

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Wastewater treatment by low-pressure membrane filtration (MF and UF) is affected to a large extent by macromolecules and colloids. In order to investigate the influence of organic colloids on the membrane filtration process, colloids were isolated from a wastewater treatment plant effluent using a rotaryevaporation pre-concentration step followed by dialysis. Stirred cell tests were carried out using redissolved colloids, with and without additional glass fiber filtration. After constant pressure membrane filtration of 190 L/m2, the initial flux had declined by 50% for colloids &gt; 6-8 kD (glass fiber filtered) with a hydrophilic MF membrane and for colloids &gt;12-14 kD (glass fiber filtered) with a hydrophobic MF membrane. For the non-filtered colloidal solutions, the flux decline was even steeper with the flux being below 10% of the initial flux after 190 L/m2 were passed through the membranes. As with larger particles, colloids form a filtration cake layer on top of the membrane surface when used as isolates without prior filtration. This filtration cake is easily removed during backwashing. However, polysaccharides as a macromolecular component of the colloid isolate cause severe fouling by the formation of a gel layer on the membrane surface that is difficult to remove completely.
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Дисертації з теми "Colloids"

1

Keal, Louis. "Dynamics of hard and soft colloids at aqueous interfaces." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066361/document.

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Анотація:
Dans cette these nous avons étudié la dynamique de colloides aux interfaces fluides. Dans une première partie nous avons étudié la dynamique de drainage de films minces liquides contenant des particules de microgels de PNiPAM. Ces systèmes sont de plus en plus utilisés pour stabiliser et déstabiliser des émulsions sur demande en jouant sur la température. Nous avons montré que la dynamique de drainage et l'épaisseur des films dépend de la concentration et du degré de réticulation des particules. Nous avons pu à partir des épaisseurs des films remonter à la conformation des particules. Les microgels moins réticulés s'étalent davantage aux interfaces à basse concentration que les particules ayant un taux de réticulation plus élevé. En revanche à haute concentration, les particules moins réticulées forment des couches plus compactes, ce qui induit des films moins stables. Dans la deuxième partie nous avons étudié la dynamique d'adsorption de particules colloidales dans des systèmes eau dans eau, obtenus par la séparation de phase de deux solutions de polymères. A temps courts, la position de la particule varie exponentiellement avec le temps alors qu'aux temps plus longs l'évolution est logarithmique. De façon surprenante, nous trouvons que dans le régime exponentiel, le temps caractéristique, qui résulte théoriquement d'un équilibre entre les forces de tension interfaciale et la friction visqueuse est trop lent par rapport à la théorie. De plus l'existence d'un régime logarithmique (habituellement attribué à un piégeage/dépiégeage de la ligne de contact) est également surprenante puisque notre système présente des tensions interfaciales très faibles, de l'ordre de 100 µN/m
This thesis examines interfacial colloidal dynamics in two separate aqueous systems. The first part aims to improve understanding of thermoresponsive microgel-stabilised emulsions. Many emulsion properties are determined by the behaviour and drainage dynamics of the thin films that form between droplets. This study reveals these drainage dynamics, achieved through observing a model thin film of PNiPAM microgel solution in air. We explore why, as other studies have shown, less cross-linked microgels stabilise emulsions more effectively than more cross-linked microgels, concluding that both adsorption dynamics and particle rearrangement under pressure play a role. Through a simple calculation, we are able to estimate the conformation of microgels at the interface, showing that microgel concentration in bulk determines the concentration at interface due to differences in adsorption kinetics, and microgel excess does not play a role. The second part of the thesis investigates behaviour of spherical colloidal particles within an Aqueous Two-Phase System (ATPS) composed of non-mixing polymer solutions of fish gelatin and dextran, with applications in low-fat foods. Additionally, the very low surface tension of these systems allows studing fast interfacial processes at experimentally accessible timescales. In this work, we examine adsorption dynamics of spherical particles, observing for the first time the theoretically-predicted exponential ‘snap-in’ stage of particle adsorption. Surprisingly, even at this low surface tension, a slower logarithmic relaxation is subsequently observed which at the oil/water interface is ascribed to pinning of the contact line on surface defects
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2

Russell, Emily Ruth. "Structure and Properties of Charged Colloidal Systems." Thesis, Harvard University, 2014. http://dissertations.umi.com/gsas.harvard:11413.

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This dissertation explores the changes in structure of colloidal systems on the introduction of repulsive interactions. Colloidal gels are well understood when all particle interactions are attractive, but their structure is fundamentally changed when repulsive interactions compete with those attractive interactions, as in the case of a binary gel of oppositely charged particles. Similarly, colloidal crystals are well understood when interactions are approximately hard-sphere, but again, the structure and material properties change when a long-range repulsion is introduced, giving a colloidal `Wigner' crystal. My research quantitatively investigates these effects in experimental model systems. I use confocal microscopy to directly image in three dimensions suspensions of micron-scale colloidal particles which are monodisperse, index- and density-matched, fluorescent, and electrostatically charged. I use standard image-processing techniques to obtain the precise location of each particle in the imaging volume in order to analyze both global and local structure. In the case of the binary gel, I observe gelation of oppositely charged particles, controlled by varying the total particle volume fraction, the interaction strength, and the mixing ratio of the two particle species. I find that contrary to commonly studied purely attractive gels, in which weakly quenched gels are more compact and less tenuous, particles in these binary gels form fewer contacts and the gels become more tenuous as we approach the gel line, and the average attractive bond number emerges as a critical parameter for gelation. This suggests that a different mechanism governs gel formation and structure in binary gels, in which attractive and repulsive interactions compete. In the case of the long-range-repulsive colloidal `Wigner' crystals, I find a body-centered-cubic crystalline phase at particle volume fractions near 15%, in contrast to the face-centered-cubic crystalline phase found at volume fractions above 50% for hard spheres. The soft interactions in these repulsive crystals permit large fluctuations, with typical particle displacements up to 20% of the nearest-neighbor spacing. I determine the three independent crystalline elastic constants, and find that the crystals are very compliant (c ~ 5-40mPa), and strongly anisotropic at all volume fractions studied. I also observe a sharp interface between the fluid and crystalline phases.
Physics
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3

Keal, Louis. "Dynamics of hard and soft colloids at aqueous interfaces." Electronic Thesis or Diss., Paris 6, 2016. http://www.theses.fr/2016PA066361.

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Анотація:
Dans cette these nous avons étudié la dynamique de colloides aux interfaces fluides. Dans une première partie nous avons étudié la dynamique de drainage de films minces liquides contenant des particules de microgels de PNiPAM. Ces systèmes sont de plus en plus utilisés pour stabiliser et déstabiliser des émulsions sur demande en jouant sur la température. Nous avons montré que la dynamique de drainage et l'épaisseur des films dépend de la concentration et du degré de réticulation des particules. Nous avons pu à partir des épaisseurs des films remonter à la conformation des particules. Les microgels moins réticulés s'étalent davantage aux interfaces à basse concentration que les particules ayant un taux de réticulation plus élevé. En revanche à haute concentration, les particules moins réticulées forment des couches plus compactes, ce qui induit des films moins stables. Dans la deuxième partie nous avons étudié la dynamique d'adsorption de particules colloidales dans des systèmes eau dans eau, obtenus par la séparation de phase de deux solutions de polymères. A temps courts, la position de la particule varie exponentiellement avec le temps alors qu'aux temps plus longs l'évolution est logarithmique. De façon surprenante, nous trouvons que dans le régime exponentiel, le temps caractéristique, qui résulte théoriquement d'un équilibre entre les forces de tension interfaciale et la friction visqueuse est trop lent par rapport à la théorie. De plus l'existence d'un régime logarithmique (habituellement attribué à un piégeage/dépiégeage de la ligne de contact) est également surprenante puisque notre système présente des tensions interfaciales très faibles, de l'ordre de 100 µN/m
This thesis examines interfacial colloidal dynamics in two separate aqueous systems. The first part aims to improve understanding of thermoresponsive microgel-stabilised emulsions. Many emulsion properties are determined by the behaviour and drainage dynamics of the thin films that form between droplets. This study reveals these drainage dynamics, achieved through observing a model thin film of PNiPAM microgel solution in air. We explore why, as other studies have shown, less cross-linked microgels stabilise emulsions more effectively than more cross-linked microgels, concluding that both adsorption dynamics and particle rearrangement under pressure play a role. Through a simple calculation, we are able to estimate the conformation of microgels at the interface, showing that microgel concentration in bulk determines the concentration at interface due to differences in adsorption kinetics, and microgel excess does not play a role. The second part of the thesis investigates behaviour of spherical colloidal particles within an Aqueous Two-Phase System (ATPS) composed of non-mixing polymer solutions of fish gelatin and dextran, with applications in low-fat foods. Additionally, the very low surface tension of these systems allows studing fast interfacial processes at experimentally accessible timescales. In this work, we examine adsorption dynamics of spherical particles, observing for the first time the theoretically-predicted exponential ‘snap-in’ stage of particle adsorption. Surprisingly, even at this low surface tension, a slower logarithmic relaxation is subsequently observed which at the oil/water interface is ascribed to pinning of the contact line on surface defects
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4

Ryan, Joseph Nolte. "Groundwater colloids in two Atlantic coastal plain aquifers : colloid formation and stability." Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/14560.

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5

Drube, Fabian. "Selfdiffusiophoretic Janus colloids." Diss., Ludwig-Maximilians-Universität München, 2013. http://nbn-resolving.de/urn:nbn:de:bvb:19-173348.

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6

Reynolds, Matthew Drake. "Colloids in groundwater." Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/15311.

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Анотація:
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1985.
MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING.
Bibliography: leaves 94-97.
by Matthew Drake Reynolds.
M.S.
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7

Batista, Vera Mónica de Oliveira. "Deformable spherical colloids." Thesis, University of Cambridge, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.610066.

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8

Chu, Fangfang. "Dumbbell-shaped colloids." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät, 2014. http://dx.doi.org/10.18452/17062.

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Анотація:
In der vorliegenden Arbeit wurde das Phasenverhalten von harten Hantelteilchen (Dumbbells) als Funktion des Aspektverhältnisses (L*, der Quotient aus dem Abstand der Massenzentren zum Durchmesser der Kugel) und der Volumendichte untersucht. Bragg-Reflexe weisen darauf hin, das harte Dumbbells mit L* < 0.4 einen Phasenübergang von einer Fluid-artigen Phase zu einem plastischen Kristall zeigen. Die experimentellen Phasendiagramme bei L* ~ 0.24 und L*~ 0.30 sind vergleichbar mit Vorhersagen aus Monte Carlo-Simulationen. Rheologie Messungen zeigen, dass harte Dumbbells verschiedene Gleichgewichts- und Nichtgleichgewichtsphasen annehmen. Suspensionen von harten Dumbbells im Zweiphasenbereich zeigen ein einziges Fließgrenzen-Ereignis, wohingegen in der plastischen Kristallphase zwei Fließgrenzen-Ereignisse beobachtet werden. Diese, im Folgenden als „double yielding“ bezeichneten Ereignisse, hängen mit der Kristallisation der Suspensionen von harten Dumbbells zusammen. Die entsprechende Strukturentwicklung wurde mit rheo-SANS-Experimenten untersucht und mithilfe von BD Simulationen interpretiert. Es konnte gezeigt werden, dass die plastische Kristallphase polykristallin im Ruhezustand ist. Unter schwacher Scherung wird eine fcc-Schwerzwilling Struktur ausgebildet. Bei hoher Scherung formt sich eine teilweise orientierte Struktur aus gleitenden Schichten. Zwischen diesen beiden Strukturen existiert eine ungeordnete Übergangsphase. Die Scher-induzierte Strukturausbildung eintspricht dem „double yielding“ Ereignis der kristallinen harten Dumbells. Es wurde gezeigt, dass ein größeres L* (L* < 0.4) die Strukturentwicklung unter Scherung qualitativ nicht beeinflusst. Aufgrund verlangsamter Dynamik in der Nähe des Glasübergangs sind lediglich stärkere oder längere Oszillationen von Nöten, um Scher-induzierte Kristallisation zu erzeugen. Im zweiten Teil dieser Arbeit werden Systeme aus hohlen Kugeln und „Janus“-Dumbbells vorgestellt, die als kolloidale Modellsysteme dienen können.
In the present work the phase behaviour of hard dumbbells has been explored as a function of aspect ratio (L*, the center to center distance to the diameter of one composed sphere) and volume fractions using thermosensitive dumbbell-shaped microgels as the hard dumbbell model system. A fluid-to-plastic crystal phase transition indicated by Bragg reflections has been observed for L* < 0.4. The experimental phase diagrams at L* ~ 0.24 and L* ~ 0.30 are comparable to the theoretical prediction of the Monte Carlo simulations. Rheological measurements reveal that the hard dumbbells in the biphasic gap show the yielding behaviour with a single yielding event, while two yielding events have been observed for the plastic crystalline phase. The two yielding events, referred to as the double yielding behaviour, are proved to be related to the crystallization of hard dumbbells. The underlying structural evolution has been investigated by rheo-SANS experiments and the scattering data has been interpreted by BD simulations. It is demonstrated that the plastic crystal structure of the hard dumbbells is polycrystalline at rest, which has been induced into the twinned fcc structure at low strain, the partially oriented sliding layers at high strain and the intermediate state at the strain in-between. The shear-induced structural evolution corresponds to the double yielding events of the fully crystallized hard dumbbells. Additionally, we prove that the increase of L* (L* < 0.4) does not change the structural evolution of the sheared hard dumbbells. Only more extensive or longer oscillations are required to form the shear-induced crystal structures due to the slowdown of the dynamics in the vicinity of the glass transition. In a second part, the work of this thesis is extended to hollow systems composed of hollow spheres and hollow Janus dumbbells that can be used as model systems to probe phase behaviour of hollow capsules.
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9

Shvets, Alexey. "Theory of colloidal stabilization by unattached polymers." Thesis, Strasbourg, 2014. http://www.theses.fr/2014STRAE025/document.

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Les dispersions colloïdales ont beaucoup d’applications technologiques importantes. A cause du mouvement brownien, les particules ont des collisions fréquentes entre elles. Les forces d’attraction de van der Waals,dérivant de potentiels à longue portés, conduisent à l’agrégation et à la précipitation des particules. Plusieurs méthodes ont été proposées pour diminuer ou contrebalancer l’effet d’attraction de van der Waals et augmenter la stabilité colloïdale. Par exemple, le choix du solvant possédant l’indice de réfraction le plus proche possible de celui des particules peut diminuer les forces de van der Waals. D'autres facteurs influencent la stabilité comme les interactions électrostatiques et les interactions spécifiques liées aux chaînes de polymères. Dans le cas des polymères, les chaînes peuvent être greffées à la surface des particules ou être dissoutes dans le solvant (chaînes libres). Dans ce travail de thèse, nous avons étudié l’effet de la stabilisation par déplétion dans le cas des chaînes de polymères libres (FPI, "free polymer induced interaction"). Des modèles théoriques précédents portent un caractère trop simplifié et utilisent des approximations sans vérification. De plus, l’influence des paramètres de la solution, c’est-à-dire, de la structure de polymères et de son interaction avec la surface de particule, n’a pas été étudiée.Les chaînes polymères libres ont été modélisées comme des marches aléatoires dans un champ moléculaire auto-cohérent qui satisfait à l'équation intégro-différentielle de diffusion. Pour le domaine moléculaire, nous avons utilisé un potentiel chimique qui, pour la solution de polymère semi-dilué, peut être représenté comme une expansion du viriel où nous n’avons pris en considération que les deuxième et troisième coefficients du viriel de la solution de polymère. En variant des paramètres tels que la rigidité du polymère, la longueur du polymère, la concentration en polymère et le régime du solvant (comme le solvant thêta), que ce soit pour une surface colloïdale purement répulsive, pour une surface adsorbée ou pour la surface d'une couche de polymère greffé, nous avons été en mesure d'améliorer la barrière répulsive due aux polymères libres entre les particules et donc nous avons trouvé des conditions de la stabilisation cinétique du système
Stable colloidal dispersions with evenly distributed particles are important for many technological applications. Due to Brownian motion colloidal particles have constant collisions with each other which often lead to their aggregation driven by the long range van der Waals attraction. As a result the colloidal systems often tend to precipitate. A number of methods have been devised to minimize the effect of long-range van der Waals attraction between colloidal particles or to override the influence of the attraction in order to provide the colloidal stability.In the PhD thesis we investigated the colloidal stabilization in solutions of free polymers which is commonly referred to as depletion stabilization. Previous theoretical studies of free-polymer induced (FPI) stabilization were based on oversimplified models involving uncontrolled approximations. Even the most basic features of the depletion stabilization phenomenon were unknown. It was unclear how the PI repulsion depends on the solution parameters, polymer structure and monomer/surface interactions.The free polymer chains were modeled as random walks in a self-consistent molecular field that satisfied to diffusion-like integro-differential equation. As the molecular field we used the chemical potential that for semi-dilute polymer solution can be represented as a virial expansion where we took into account only second and third virial coefficients of the polymer solution. Varying the parameters like polymer stiffness, polymer length, polymer concentration and solvent regime (like theta solvent) whether it is for purely repulsive colloidal surface, adsorbed surface or surface with grafted polymer layer we were able to enhance the repulsive barrier due to the free polymers between the particles and therefore found conditions for kinetic stabilization of the system
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10

Kemp, Roger. "Colloids in external fields." Thesis, University of Bristol, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.508084.

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Книги з теми "Colloids"

1

Dickinson, Eric, and Martin E. Leser, eds. Food Colloids. Cambridge: Royal Society of Chemistry, 2007. http://dx.doi.org/10.1039/9781847557698.

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Dickinson, Eric, ed. Food Colloids. Cambridge: Royal Society of Chemistry, 2007. http://dx.doi.org/10.1039/9781847552389.

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Dickinson, Eric, and Reinhard Miller, eds. Food Colloids. Cambridge: Royal Society of Chemistry, 2001. http://dx.doi.org/10.1039/9781847550842.

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4

Daniels, Eric S., E. David Sudol, and Mohamed S. El-Aasser, eds. Polymer Colloids. Washington, DC: American Chemical Society, 2001. http://dx.doi.org/10.1021/bk-2002-0801.

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5

Priestley, Rodney, and Robert Prud'homme, eds. Polymer Colloids. Cambridge: Royal Society of Chemistry, 2019. http://dx.doi.org/10.1039/9781788016476.

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6

R, Buscall, Corner T, and Stageman J. F, eds. Polymer colloids. London: Elsevier Applied Science Publishers, 1985.

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7

Prof, Caruso Frank, ed. Colloids and colloid assemblies: Synthesis, modification, organization, and utilization of colloid particles. Weinheim: Wiley-VCH, 2004.

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8

Peter, Griffiths, and SpringerLink (Online service), eds. UK Colloids 2011: An International Colloid and Surface Science Symposium. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012.

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9

Tadros, Tharwat F. Colloids in Agrochemicals. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2009. http://dx.doi.org/10.1002/9783527631155.

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10

Tadros, Tharwat F. Colloids in Paints. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2010. http://dx.doi.org/10.1002/9783527631179.

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Частини книг з теми "Colloids"

1

Lekkerkerker, Henk N. W., Remco Tuinier, and Mark Vis. "Phase Behaviour of Colloidal Cubes Mixed with Depletants." In Colloids and the Depletion Interaction, 319–42. Cham: Springer International Publishing, 2024. http://dx.doi.org/10.1007/978-3-031-52131-7_10.

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AbstractIn Chaps. 8 and 9 it was shown that the phase behaviour of anisotropic hard particles is considerably richer than that of hard spheres (see Sect. 3.2). Recent breakthroughs in colloidal synthesis allow the control of particle shapes and properties with high precision. This provides us with a constantly expanding library of new anisotropic building blocks, thus opening new avenues to explore colloidal self-assembly at a higher level of complexity [1, 2]. One of these intriguing novel systems is cube-like colloids. In this chapter, a selective overview is given on the current knowledge of the phase behaviour of cube-like colloids with and without added depletants.
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2

Abbasi, Adeel, Francis DeRoos, José Artur Paiva, J. M. Pereira, Brian G. Harbrecht, Donald P. Levine, Patricia D. Brown, et al. "Colloids." In Encyclopedia of Intensive Care Medicine, 587–90. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-00418-6_264.

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3

Boily, Jean-François. "Colloids." In Encyclopedia of Earth Sciences Series, 1–4. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-39193-9_91-1.

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4

Boily, Jean-François. "Colloids." In Encyclopedia of Earth Sciences Series, 294–97. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-39312-4_91.

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Coussot, Philippe. "Colloids." In Rheophysics, 157–99. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-06148-1_5.

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6

Vincent, Brian, J. Th G. Overbeek, and M. J. Sparnaay. "Colloids." In 100 Years of Physical Chemistry, 207–24. Cambridge: Royal Society of Chemistry, 2007. http://dx.doi.org/10.1039/9781847550002-00207.

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7

Pantaleon, Lucas. "Colloids." In Equine Fluid Therapy, 312–22. Hoboken, NJ: John Wiley & Sons, Inc, 2014. http://dx.doi.org/10.1002/9781118928189.ch24.

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Satya Prakash, M. V. S., and Kirthiha Govindaraj. "Colloids." In Transfusion Practice in Clinical Neurosciences, 35–47. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-0954-2_4.

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9

Murtaugh, Robert J. "Colloids." In Critical Care, 26–27. New York: Routledge, 2021. http://dx.doi.org/10.1201/9781315140629-14.

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10

Salhotra, Ripenmeet, Adrian Wong, and Manu L. N. G. Malbrain. "The Place for Starches and Other Colloids." In Rational Use of Intravenous Fluids in Critically Ill Patients, 243–57. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-42205-8_11.

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AbstractThis chapter provides a comprehensive review of synthetic colloids, specifically hydroxyethyl starch (HES) solutions, and their role in resuscitation of critically ill, perioperative, and trauma patients. This chapter addresses various questions, including the crystalloid versus colloid debate, the strengths and weaknesses of different fluid trials and meta-analyses, and the specific situations or patient groups where colloids may have an advantage. This chapter focuses on the results of five major trials that compare the use of crystalloids versus colloids in critically ill patients. The 6S study and the CHEST trial confirmed the suspicion of renal damage associated with HES solutions, and the European Medicines Agency’s (EMA) safety committee prohibited the use of HES solutions in critically ill, septic, and burn patients, or those with kidney injury in 2013. However, many questions and controversies remained thereafter and more recently the European Commission has suspended the marketing authorizations of HES solutions for infusion. The use of HES and other synthetic colloids should be restricted to resuscitation in the perioperative setting or in limited volumes with extreme caution in trauma settings outside of the EU. The take-home messages include the availability of natural and synthetic colloids, the lack of outcome benefit in clinical trials, the association of HES with renal failure and increased use of renal replacement therapy, and the unsafe use of synthetic colloids in perioperative patients. This chapter recommends limiting the dose of synthetic colloids to 30ml/kg when given in the peri- and postoperative phase.
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Тези доповідей конференцій з теми "Colloids"

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Hannun, Jamal, and Riyadh Al-Raoush. "Retention of Hydrophobic Colloids in Unsaturated Porous Media using Microfluidics." In The 2nd International Conference on Civil Infrastructure and Construction. Qatar University Press, 2023. http://dx.doi.org/10.29117/cic.2023.0177.

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Water recharge wells can provide a solution for 3.5 billion people, living in regions suffering from water scarcity. Due to fines migration, freshwater wells that are used to recharge aquifers, often experience expedited deterioration. Colloidal clay fine particles can be mobilized from within aquifers due to hydrodynamic forces or the sweeping of gas-water interface (GWI). The released colloids concentration increases then starts to retain and clog at the pores within the aquifer formation. Although fines migration is responsible for decommissioning many recharge wells, yet there is a lack of pore scale observations that uncover clogging mechanisms within porous media. Thus, this study utilizes wide-field optical macroscopy and microfluidic models with pore morphology of sandstone, to investigate the clogging mechanisms of hydrophobic colloids. The aim is to discover how interfacial surfaces within porous media retain colloids. Hence imbibition and drainage of colloidal suspension were carried to vary water saturation. Flow experiments were imaged at a resolution of 1µm/pixel, while colloids diameter was 5 µm. Images were segmented into solid, water, gas and colloids. Then the amount of colloids retained on each interface was quantified. Findings revealed that hydrophobic colloids retained mainly on the GWI. For colloids suspension in deionized water, affinity of colloids to GWI was high enough to cause bubble stabilization. In both hydrophobic and hydrophilic porous media, colloids disconnected the gas phase to create larger GWI surface. More than 90% of hydrophobic colloids were cleaned from the media after drainage, uncovering an efficient remediation technique for water aquifer.
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2

Jen, Chun-Ping, and Neng-Chuan Tien. "Investigation of Colloid-Facilitated Effects on the Radionuclides Migration in the Fractured Rock With a Kinetic Solubility-Limited Dissolution Model." In ASME 2010 13th International Conference on Environmental Remediation and Radioactive Waste Management. ASMEDC, 2010. http://dx.doi.org/10.1115/icem2010-40001.

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Nuclides can move with the groundwater either as solutes or colloids, where the latter mechanism generally results in much shorter traveling time as they interact strongly with solid phases, such as actinides. It is therefore essential to assess the relative importance of these two transport mechanisms for different nuclides. The relative importance of colloids depends on the nature and concentration of colloids in groundwater. Plutonium (Pu), neptunium (Np), uranium (U) and americium (Am) are four nuclides of concern for long-term emplacement of nuclear wastes at potential repository sites. If attached to iron oxide, clay or silica colloids in groundwater. Strong sorption of the actinides by colloids in groundwater may facilitate transport of these nuclides along potential flow paths. Solubility-limited dissolution model models can be used to determine the release of the safety assessment for nuclear waste in geological disposal sites. The present study investigates the effect of colloid on the transport of solubility limited nuclide under the kinetic solubility limited dissolution (KSLD) boundary condition in fractured media. The release rate of nuclide would proportional to the difference between the saturation concentration and the inlet aqueous concentration of nuclide. The presence of colloids could decrease the aqueous concentration of nuclide and thus could increase the release flux of nuclide from the waste form.
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3

Amme, M., H. Lang, and M. Sto¨ckl. "Different Pathways of Secondary Phase Formation Induced by Colloidal and Dissolved Silica During the Dissolution of UO2 Nuclear Fuel in Leaching Tests." In ASME 2003 9th International Conference on Radioactive Waste Management and Environmental Remediation. ASMEDC, 2003. http://dx.doi.org/10.1115/icem2003-4504.

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We investigated the different dissolution behaviour of UO2 nuclear fuel material in waters containing silica in two different physical and chemical forms (dissolved ions and as SiO2 colloids, respectively) at elevated temperatures (95 °C in autoclaves). It was investigated if SiO2 colloids can act as carrier material for U ions during a interface geochemical dissolution process, a process that might possibly enhance the mobilization of uranium. Herefore, leaching / dissolution tests were conducted in batch reactors, using both dissolved Si (sodium metasilicate solution), as well as synthetic SiO2 colloids (100 nm diameter). Solid materials were examined with scanning electron microscopy (SEM-EDX) after the tests and ICP-OES was used for analysis of concentrations of U and Si in solutions. Thermodynamic calculations were applied for modelling the surface charges of the solid materials. Results show that a treatment with colloidal SiO2 has different effects on the surfaces than a leaching in dissolved silicate solutions. In the presence of colloids, well-crystallized secondary phases containing U and Si (most obviously uranyl silicates) were found on the surfaces, which were attacked by the treatment. This was not the case when dissolved Si was used. SiO2 colloids were partly found to remain on the surfaces after 1000 h at 95 °C. Dissolved U concentrations decreased with increasing Si content in the systems, especially so when colloidal Si was used. Ultrafiltration showed that the greatest part of the dissolved U was associated with Si colloids. A surface charge model suggests that the different effects are due to the development of electrostatic interactions between the UO2 and SiO2 surfaces.
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4

Lawandy, N. M., and R. MacDonald. "Optical Debye effect." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1990. http://dx.doi.org/10.1364/oam.1990.wv6.

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The interaction of acoustic waves with charged colloids results in electrical signals. This phenomena, known as the Debye effect, results due to the instantaneous separation between the charged colloidal particle and its surrounding double layer. The separation results in a macroscopic polarization within the medium, which creates a voltage difference. This work demonstrates that radiation pressure forces can be used to impulsively move the colloid, resulting in a dipolar electric field. Experiments were performed using 100 ps, 1.06-µm pulses and 80 ps, 532-nm pulses incident on aqueous colloidal suspensions of charged latex spheres. Experiments were performed on random colloidal suspensions as well as high density crystals ordered in an fcc lattice. The dependence of the effect on sphere size and pulse intensity are presented. The effect exhibits the expected polarity when opposite sides of the sample are illuminated. Using electro-optic sampling, the dynamics of the double layer response can be directly probed on a picosecond time scale.
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5

Yamamoto, T., Y. Tabe, and H. Yokoyama. "Photochemical manipulation of colloidal structures in liquid-crystal colloids." In International Congress on Optics and Optoelectronics, edited by Milada Glogarova, Peter Palffy-Muhoray, and Martin Copic. SPIE, 2007. http://dx.doi.org/10.1117/12.722656.

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6

Albaba, Mhd Taisir, Jamal Hannun, and Riyadh Al-Raoush. "Impact of Pore Morphology on Colloid Migration at Variable Saturation Levels of Natural Porous Media." In The 2nd International Conference on Civil Infrastructure and Construction. Qatar University Press, 2023. http://dx.doi.org/10.29117/cic.2023.0167.

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The migration of colloids within porous media has a critical impact on many important industrial processes such as oil production and groundwater recharge. Colloids can clog the pore space and hence impair the permeability of fluids which adversely impacts the efficiency of fluids movement through such media. Therefore, understanding the mechanisms of pore clogging at the pore-scale is critical to develop efficient remediation methodologies for permeability reduction at different physio-chemical conditions. To study pore clogging at a pore-scale, microfluidic chips were fabricated to mimic geometries of natural porous media extracted from tomographic scans of sand packs. A colloidal suspension was injected in three phases into the system. The phases consisted of an initial imbibition of the suspension, followed by drainage of the suspension from the system, and finally, a second imbibition. During each phase, a series of images are taken of a section of the porous media. Findings reveal that pore-clogging considerably impairs saturation levels of the porous media through blocking the flow from reaching the gas phase within the system. Considerably increasing the time the gas is trapped in the pore-space, which in turn develops higher irreducible water saturation. This was also observed in the case of drainage of the colloidal suspension from the pore-space where colloids blocked pathways of the gas phase and prevented its migration through the pore space. In contrast, the migration of colloids was also impacted by the presence of the gas phase. Gas provided a clogging surface while forcing colloids to migrate through the pore space and accumulate at other pores. This implies that gas phase presence within a low porosity system can increase pore clogging at a significant rate. This is also supported by the short period between the clogging of two pores and the clogging of a dozen pores within the observed system.
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7

Callegari, Agnese, Alessandro Magazzù, Andrea Gambassi, and Giovanni Volpe. "Optical Trapping and Critical Casimir Forces." In Optical Manipulation and Its Applications. Washington, D.C.: Optica Publishing Group, 2023. http://dx.doi.org/10.1364/oma.2023.am4d.4.

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Critical Casimir forces between colloidal particles act at distances reaching often hundreds of nanometers. Keeping colloids at such distances is a major experimental challenge. Here, we review how optical tweezers help quantitatively in studying critical Casimir forces acting on particles in suspensions.
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8

Cheng, Xinguang, Satyajyoti Senapati, and Hsueh-Chia Chang. "Separation of Nanocolloids by Taylor Cone Harmonics." In ASME 2009 Second International Conference on Micro/Nanoscale Heat and Mass Transfer. ASMEDC, 2009. http://dx.doi.org/10.1115/mnhmt2009-18060.

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The conducting Taylor cone can activate specified harmonics of Laplace equation near the cone and can generate field maxima at multiple discrete polar angles. As the nanocolloids are ejected out from the cone tip, the difference of dominating forces in axial and transverse direction defines size-dependent initial angle before the colloids are trapped by the field maxima of the harmonics at the closest polar angle. This size-dependent selection of harmonics governs the different size colloids to travel along different trajectories and form separated deposition in the downstream of the electrospray. This electrospray-based separation of nanocolloids is successfully used to detect DNA hybridization. A family of cone shape is generated by changing voltage in a finite range. Variation of Taylor cone angle changes the harmonics and the trajectory of colloid is found to shift to a larger polar angle under higher voltage.
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9

Zitha, Pacelli L. J. "Water Control by Bridging Colloids." In SPE European Formation Damage Conference. Society of Petroleum Engineers, 1997. http://dx.doi.org/10.2118/38198-ms.

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10

Tartaglia, P., Michio Tokuyama, Irwin Oppenheim, and Hideya Nishiyama. "Models of Gel-Forming Colloids." In COMPLEX SYSTEMS: 5th International Workshop on Complex Systems. AIP, 2008. http://dx.doi.org/10.1063/1.2897803.

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Звіти організацій з теми "Colloids"

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Santschi, Peter, and Gary A. Gill. Estuarine Colloids: Sorption Capacity, Colloid Facilitated Transport and Bioavailibility. Fort Belvoir, VA: Defense Technical Information Center, July 1994. http://dx.doi.org/10.21236/ada283076.

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2

Keith P. Johnston. MOLECULAR DESIGN OF COLLOIDS IN SUPERCRITICAL FLUIDS. Office of Scientific and Technical Information (OSTI), April 2009. http://dx.doi.org/10.2172/950785.

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3

Abdel-Fattah, Amr I. Chancellor Water Colloids: Characterization and Radionuclide Association. Office of Scientific and Technical Information (OSTI), June 2012. http://dx.doi.org/10.2172/1044090.

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4

Reimus, Paul William, and Hakim Boukhalfa. Chancellor Water Colloids: Characterization and Radionuclide Associated Transport. Office of Scientific and Technical Information (OSTI), September 2014. http://dx.doi.org/10.2172/1158841.

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5

Beam, Jeremiah. Actinide (III/IV) - Silica Colloids in the WIPP. Office of Scientific and Technical Information (OSTI), November 2022. http://dx.doi.org/10.2172/1897411.

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Ashley N. Westbrook. CHARACTERIZATION OF POLYLACTIC ACID COLLOIDS FOR IN SITU BIOREMEDIATION. Office of Scientific and Technical Information (OSTI), July 2003. http://dx.doi.org/10.2172/910733.

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7

López de la Manzanara Pérez, Sofía, and Juan de Vicente Álvarez-Manzaneda. Magneto-rheological fluids; nonlinear dynamics in non-stationary triaxial magnetic fields. Fundación Avanza, May 2023. http://dx.doi.org/10.60096/fundacionavanza/2462022.

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Анотація:
This project aims to study the behavior of magnetorheological fluids under the influence of an external rotational magnetic field, with the main focus on analyzing the velocities of colloids present in the samples.
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Henderson, Don O. Metal colloids and quantum dots: linear and nonlinear optical properties. Office of Scientific and Technical Information (OSTI), May 1997. http://dx.doi.org/10.2172/799350.

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Gschwend, Philip M., Carol R. Johnson, Nikolaos P. Nikolaidis, and Luca A. Hellerich. Manipulating Subsurface Colloids to Enhance Cleanup of DOE Waste Sites. Office of Scientific and Technical Information (OSTI), June 1999. http://dx.doi.org/10.2172/827249.

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10

Nisoli, Cristiano. On the Equivalence of Trapped Colloids, Pinned Vortices, and Spin Ice. Office of Scientific and Technical Information (OSTI), April 2014. http://dx.doi.org/10.2172/1129812.

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