subject:(Colloid)

University of Alberta

1. Molla, Shahnawaz Hossain. AC Electrokinetic Manipulation of Colloids during Filtration.

Degree: PhD, Department of Mechanical Engineering, 2009, University of Alberta

URL: https://era.library.ualberta.ca/files/mp48sd82f

► The work presented in this dissertation provides a novel technique of manipulation of colloidal entities during membrane filtration based on an AC electrokinetic phenomenon called… (more)

▼ The work presented in this dissertation provides a novel technique of manipulation of colloidal entities during membrane filtration based on an AC electrokinetic phenomenon called dielectrophoresis. First, the influence of dielectrophoretic (DEP) forces created on a membrane surface to levitate colloidal particles is studied both theoretically and experimentally. A numerical model based on the convection-diffusion-migration equation is presented to calculate the concentration distribution of colloidal particles in shear flow under the influence of a repulsive DEP force field. The simulation results indicate that particle accumulation on the membrane (or membrane fouling) during filtration can be averted by creating a repulsive DEP force field on the membrane surface. Corresponding experimental study employs a microelectrode array on a glass surface in a tangential flow cell, to apply repulsive DEP forces on polystyrene particles suspended in an aqueous medium. Applying a non-uniform AC electric field on the microelectrodes generates the DEP force field that levitates the polystyrene particles above the surface. This study indicates that the repulsive dielectrophoretic forces imparted on the particles suspended in the feed can be employed to effectively mitigate membrane fouling in a crossflow membrane filtration process. The second phase of the study is aimed at controlling colloid transport through a microporous membrane using DEP forces acting across the pores. A theoretical analysis of colloid transport through straight cylindrical capillaries in the presence of a non-uniform AC electric field is developed. Numerical simulations demonstrate that the interaction of the particles with the electric field generates strong repulsive DEP forces, acting selectively on the colloidal particles to control particle transport through the pore. A combination of DEP forces and size exclusion in porous material is proposed to develop an energy efficient technique for colloid filtration. Experimental results on this steric-dielectrophoretic filtration are also obtained using novel ``sandwich membranes" and colloidal suspensions in a dead-end filtration system. The primary advantage of this steric-dielectrophoretic mechanism is that the filtration can be achieved by filter media (such as membranes) that have considerably larger pore sizes than the retained colloids. The technique can also result in tunable filtration mechanisms, where particles with same size but different electrical properties can be separated using suitably designed membranes.

Subjects/Keywords: Electrokinetic; Membrane; Colloid; Filtration; AC

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APA (6^th Edition):

Molla, S. H. (2009). AC Electrokinetic Manipulation of Colloids during Filtration. (Doctoral Dissertation). University of Alberta. Retrieved from https://era.library.ualberta.ca/files/mp48sd82f

Chicago Manual of Style (16^th Edition):

Molla, Shahnawaz Hossain. “AC Electrokinetic Manipulation of Colloids during Filtration.” 2009. Doctoral Dissertation, University of Alberta. Accessed March 01, 2021. https://era.library.ualberta.ca/files/mp48sd82f.

MLA Handbook (7^th Edition):

Molla, Shahnawaz Hossain. “AC Electrokinetic Manipulation of Colloids during Filtration.” 2009. Web. 01 Mar 2021.

Vancouver:

Molla SH. AC Electrokinetic Manipulation of Colloids during Filtration. [Internet] [Doctoral dissertation]. University of Alberta; 2009. [cited 2021 Mar 01]. Available from: https://era.library.ualberta.ca/files/mp48sd82f.

Council of Science Editors:

Molla SH. AC Electrokinetic Manipulation of Colloids during Filtration. [Doctoral Dissertation]. University of Alberta; 2009. Available from: https://era.library.ualberta.ca/files/mp48sd82f

Penn State University

2. Fleming, David Andrew. Functional Nanoparticles: Synthesis and Application .

Degree: 2008, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/7444

► Nanoparticles have attracted much attention due to their potential applications in, for example, magnetic recording, optical detection and medical diagnostics. The control of nanoparticle size,… (more)

▼ Nanoparticles have attracted much attention due to their potential applications in, for example, magnetic recording, optical detection and medical diagnostics. The control of nanoparticle size, shape and composition is essential because each affects physical properties, while control over surface functionality is necessary to realize potential uses. As a result, the synthesis and chemical surface modification of noble metal and magnetic nanoparticles is therefore presented. Au nanoparticles with diameters ranging from 4 - 15 nm and with low polydispersity were synthesized in molten trioctylphosphine oxide/hexadecylamine solutions through the amine mediated reduction of Au(acac)PPh3. The rate of particle growth and subsequent aggregation was strongly dependent on the relative concentrations of protecting ligands and was monitored by both transmission electron microscopy and UV-visible absorption spectroscopy. This scheme was subsequently amended to the growth of thiol, amine, or phosphine protected Au seeds. An aqueous route for the production of gold-coated ã-Fe2O3 and partially oxidized Fe3O4 through hydroxylamine iterative seeding was also explored. Au shell growth was confirmed by transmission electron microscopy and tracked via UV-Vis spectroscopy. Core/shell particle magnetic properties were investigated using SQUID magnetometry and where shown to remain constant during Au deposition. Place exchange reactions were used to functionalize FePt with electroactive groups. Here, ferrocene thiol was incorporated into the FePt supporting ligand monolayer. Cyclic voltammetry revealed that particle motion was mass transport limited, and a diffusion coefficient was calculated. Microelectrode voltammetry revealed that applied magnetic fields did not effect particle diffusion. Au particles were also subject to place exchange with ù-bromo-functionalized thiol and the Br termini were subsequently converted to azides. These were then reacted with a series of alkynyl-derivatized small molecules in nonpolar solutions which led to their attachment through the formation of a 1,2,3-triazole ring. These click reactions were used to impart chemical functionality to the Au particles, which was assessed using fluorescence spectroscopy and cyclic voltammetry. The ability of electrostatically stabilized Au nanoparticles to selectively deposit onto amine-patterned glass substrates is lastly investigated. In addition, the syntheses of several classes of noble metal particles again functionalized via place exchange were implicated for additional attachment chemistries. Strategies aimed at directing the assembly of these particles to specific areas of patterned substrates were likewise investigated. Advisors/Committee Members: Mary Elizabeth Williams, Committee Chair/Co-Chair, Thomas E Mallouk, Committee Member, Christine Dolan Keating, Committee Member, William O Hancock, Committee Member.

Subjects/Keywords: nanoparticles; colloid

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APA (6^th Edition):

Fleming, D. A. (2008). Functional Nanoparticles: Synthesis and Application . (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/7444

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Fleming, David Andrew. “Functional Nanoparticles: Synthesis and Application .” 2008. Thesis, Penn State University. Accessed March 01, 2021. https://submit-etda.libraries.psu.edu/catalog/7444.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Fleming, David Andrew. “Functional Nanoparticles: Synthesis and Application .” 2008. Web. 01 Mar 2021.

Vancouver:

Fleming DA. Functional Nanoparticles: Synthesis and Application . [Internet] [Thesis]. Penn State University; 2008. [cited 2021 Mar 01]. Available from: https://submit-etda.libraries.psu.edu/catalog/7444.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Fleming DA. Functional Nanoparticles: Synthesis and Application . [Thesis]. Penn State University; 2008. Available from: https://submit-etda.libraries.psu.edu/catalog/7444

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North Carolina State University

3. Stamm, Lindsey Brooks Jerrim. Meniscus-Directed Assembly of Biologically Active Coatings of Cells, Microparticles, and Nanoparticles.

Degree: PhD, Chemical Engineering, 2009, North Carolina State University

URL: http://www.lib.ncsu.edu/resolver/1840.16/3552

► Convective assembly principles and techniques were used in two complementary studies for depositing close packed yeast-coated surfaces and gold nanoparticle wires. Convective assembly at high… (more)

▼ Convective assembly principles and techniques were used in two complementary studies for depositing close packed yeast-coated surfaces and gold nanoparticle wires. Convective assembly at high volume fraction was used for the rapid deposition of uniform, close-packed coatings of Saccharomyces cerevisiae onto glass slides. A computational model was developed to calculate the thickness profiles of such coatings for various experimental conditions. Both experimentation and numerical simulations demonstrated that the deposition process is strongly affected by the presence of sedimentation. The deposition device was inclined to increase the uniformity of the coatings by causing the cells to sediment toward the three-phase contact line. In accordance with the simulation, the experiments showed that both increasing the angle of the device and decreasing the angle between the slides increased the uniformity of the deposited coatings. Finally, the Ã¢â‚¬Å“convective-sedimentationÃ¢â‚¬Â assembly method was used to deposit composite coatings of live cells and large latex particles as an example of biologically active composite coatings. These coatings were allowed to proliferate and demonstrate a proof-of-concept of a self-cleaning surface. Two methods were developed for the deposition of micro- and nanoparticles into linear assemblies that could be used in biosensors and biomaterials. In capillary-guided deposition, a capillary is withdrawn across a wettable substrate, resulting in the assembly of a particle line. We characterized the effects of particle concentration and withdrawal speed and correlated them to structure of the deposited assemblies. The particles are assembled into one of three different structures, depending on the particle volume fraction and deposition speed. We demonstrate that the metallic nanoparticle lines are Ohmically conductive. Using wedge-templated deposition, linear assemblies were deposited from sessile droplets on moderately hydrophobic surfaces. The particles convectively assemble at the freely-receding three-phase contact line and are pulled into a line against the wedge. The deposited lines can be long and narrow with a few breaks or significantly wider and shorter but unbroken. These methods could be used for engineered patterning of nanoparticle structures on surfaces. Advisors/Committee Members: Orlin Velev, Committee Chair (advisor), Anne Lazarides, Committee Member (advisor), Jan Genzer, Committee Member (advisor), Christine Grant, Committee Member (advisor), Carol Hall, Committee Member (advisor).

Subjects/Keywords: nanoparticle; cell coating; colloid

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APA (6^th Edition):

Stamm, L. B. J. (2009). Meniscus-Directed Assembly of Biologically Active Coatings of Cells, Microparticles, and Nanoparticles. (Doctoral Dissertation). North Carolina State University. Retrieved from http://www.lib.ncsu.edu/resolver/1840.16/3552

Chicago Manual of Style (16^th Edition):

Stamm, Lindsey Brooks Jerrim. “Meniscus-Directed Assembly of Biologically Active Coatings of Cells, Microparticles, and Nanoparticles.” 2009. Doctoral Dissertation, North Carolina State University. Accessed March 01, 2021. http://www.lib.ncsu.edu/resolver/1840.16/3552.

MLA Handbook (7^th Edition):

Stamm, Lindsey Brooks Jerrim. “Meniscus-Directed Assembly of Biologically Active Coatings of Cells, Microparticles, and Nanoparticles.” 2009. Web. 01 Mar 2021.

Vancouver:

Stamm LBJ. Meniscus-Directed Assembly of Biologically Active Coatings of Cells, Microparticles, and Nanoparticles. [Internet] [Doctoral dissertation]. North Carolina State University; 2009. [cited 2021 Mar 01]. Available from: http://www.lib.ncsu.edu/resolver/1840.16/3552.

Council of Science Editors:

Stamm LBJ. Meniscus-Directed Assembly of Biologically Active Coatings of Cells, Microparticles, and Nanoparticles. [Doctoral Dissertation]. North Carolina State University; 2009. Available from: http://www.lib.ncsu.edu/resolver/1840.16/3552

University of Waikato

4. Jaine, Jacob Evan. A study on rhodium and palladium mixed-media sols .

Degree: 2011, University of Waikato

URL: http://hdl.handle.net/10289/5295

► Historically the majority of precious metal sols have been prepared in an aqueous medium, while a much smaller proportion have been prepared in various non‐aqueous… (more)

▼ Historically the majority of precious metal sols have been prepared in an aqueous medium, while a much smaller proportion have been prepared in various non‐aqueous solvents. Few however have been prepared in mixtures of the two, this paucity being the raison d’être of this study. The goal therefore was to perform a systematic investigation of the changes in the properties of rhodium and palladium sols generated in mixtures of water and another organic cosolvent across a range of volumetric compositions. Six cosolvents were investigated: methanol, dimethylsulfoxide, acetonitrile, N,N‐dimethylformamide, acetone, and tetrahydrofuran. To stabilise the resulting sols against aggregation four protecting agents were used: poly(vinyl pyrrolidone), poly(vinyl alcohol), poly(acrylic acid), and arabinogalactan, which was a newly‐available polysaccharide extracted from the Western Larch tree. To reduce the metals from their precursor salts, sodium borohydride and hydrazine hydrate were used. The resulting colloids were analysed by Transmission Electron Microscopy (TEM), Photon Correlation Spectroscopy (PCS) and Ultraviolet/Visible Spectrophotometry. The size of the primary particles in the resulting sols was shown by TEM to be inversely proportional to the proportion of cosolvent in which they were generated. A theory was postulated to account for these changes based on temporary stabilisation of the metal nuclei by adsorption of cosolvent molecules. The characteristics of the aggregates observed in the TEM micrographs were shown to be independent of the cosolvent proportion, changing progressively but unpredictably across the composition ranges studied for most systems. This behaviour was believed to be caused by changes in the conformations of the protecting agents, which depended nonlinearly on the composition of the dispersion medium in which they were used. The measurements collected in‐situ by both PCS and UV/Vis were considered to be good indicators of the levels of aggregation observed in the sols ex‐situ by TEM, with any disparities between the two sets of measurements rationalised with relative ease. PCS measurements gave average hydrodynamic diameters of approximately 20 nm – 80 nm for sols generated in purely aqueous dispersion media, depending on the metal and protecting agent used. Infrared spectra were collected of carbon monoxide adsorbed to the surface of the particles of the sols in mixed‐media to determine the effect of the cosolvent proportion on ν(CO)ads. Sols generated for the aforementioned work were found to be of insufficient density for this purpose, so a series of high‐density sols were synthesised especially. Adsorbed CO was successfully detected on rhodium sols in mixtures of water and either MeOH, DMF, DMSO or MeCN. In these cases υ(CO)ads and its intensity decreased as the cosolvent proportion was increased. This behaviour was rationalised by competitive adsorption of the cosolvent molecules onto the surface of the colloidal particles, precluding the adsorption of CO molecules. The consequent… Advisors/Committee Members: Mucalo, Michael R (advisor).

Subjects/Keywords: colloid; nanoparticle; sol; rhodium; palladium

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Jaine, J. E. (2011). A study on rhodium and palladium mixed-media sols . (Masters Thesis). University of Waikato. Retrieved from http://hdl.handle.net/10289/5295

Chicago Manual of Style (16^th Edition):

Jaine, Jacob Evan. “A study on rhodium and palladium mixed-media sols .” 2011. Masters Thesis, University of Waikato. Accessed March 01, 2021. http://hdl.handle.net/10289/5295.

MLA Handbook (7^th Edition):

Jaine, Jacob Evan. “A study on rhodium and palladium mixed-media sols .” 2011. Web. 01 Mar 2021.

Vancouver:

Jaine JE. A study on rhodium and palladium mixed-media sols . [Internet] [Masters thesis]. University of Waikato; 2011. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/10289/5295.

Council of Science Editors:

Jaine JE. A study on rhodium and palladium mixed-media sols . [Masters Thesis]. University of Waikato; 2011. Available from: http://hdl.handle.net/10289/5295

University of Toronto

5. Spanik, Sean Patrick. Comparing Favorable and Unfavorable Attachment of Colloids in a Discrete Sandstone Fracture.

Degree: 2017, University of Toronto

URL: http://hdl.handle.net/1807/79153

►

This study compares the results of cationic amine-modified latex (favorable attachment) and anionic carboxylate modified latex (unfavorable attachment) microsphere transport through a discrete sandstone fracture.… (more)

Subjects/Keywords: Colloid; Fractured Rock; 0775

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Spanik, S. P. (2017). Comparing Favorable and Unfavorable Attachment of Colloids in a Discrete Sandstone Fracture. (Masters Thesis). University of Toronto. Retrieved from http://hdl.handle.net/1807/79153

Chicago Manual of Style (16^th Edition):

Spanik, Sean Patrick. “Comparing Favorable and Unfavorable Attachment of Colloids in a Discrete Sandstone Fracture.” 2017. Masters Thesis, University of Toronto. Accessed March 01, 2021. http://hdl.handle.net/1807/79153.

MLA Handbook (7^th Edition):

Spanik, Sean Patrick. “Comparing Favorable and Unfavorable Attachment of Colloids in a Discrete Sandstone Fracture.” 2017. Web. 01 Mar 2021.

Vancouver:

Spanik SP. Comparing Favorable and Unfavorable Attachment of Colloids in a Discrete Sandstone Fracture. [Internet] [Masters thesis]. University of Toronto; 2017. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/1807/79153.

Council of Science Editors:

Spanik SP. Comparing Favorable and Unfavorable Attachment of Colloids in a Discrete Sandstone Fracture. [Masters Thesis]. University of Toronto; 2017. Available from: http://hdl.handle.net/1807/79153

University of Waikato

6. Jaine, Jacob Evan. A Study on Supported Metal Catalysts Prepared from Colloidal Precursors .

Degree: 2016, University of Waikato

URL: http://hdl.handle.net/10289/9981

► When metal nanoparticles are supported on the surface of an inert carrier, the resulting materials can become powerful heterogeneous catalysts capable of accelerating a diverse… (more)

▼ When metal nanoparticles are supported on the surface of an inert carrier, the resulting materials can become powerful heterogeneous catalysts capable of accelerating a diverse range of chemical reactions. Though there are a wide variety of synthetic routes by which these materials can be prepared, many offer little control over the textural properties of the resulting catalyst. Conversely, methods using pre-formed colloidal nanoparticles as a metal source offer the potential for precise control of properties like particle size and shape. This is both a topical class of syntheses, and the subject of the current body of work. Three different types of colloids were therefore prepared using different stabilising agents, and subsequently used to produce an array of different catalysts. As support materials for the catalysts, a series of four commercially available materials were obtained, including silica, alumina, hydroxyapatite, and microcrystalline cellulose. Four novel analogues were also obtained, including halloysite, perlite, bioapatite, and macrofibrillar cellulose. In order to understand their physicochemical properties, they were characterised by a combination of Fourier transform infrared microspectroscopy, solid-state ¹H, ¹³C, ²⁷Al, ²⁹Si, and ³¹P nuclear magnetic resonance spectroscopy, x-ray diffraction, x-ray fluorescence spectroscopy, scanning and transmission electron microscopy, laser diffraction analysis, and zeta potential measurements. Additional experiments were performed to investigate the wetting properties of the materials using the Washburn capillary rise method, which was shown to be a valuable method for rationalising solvent choice for reactions involving these materials. An initial batch of catalysts was produced by immobilising electrostatically-stabilised rhodium, palladium, and platinum colloids onto these support materials. Instrumental characterisation of the catalysts showed no major perturbation to the chemistry of the materials following the immobilisation, though some subtle surface effects were observed. These catalysts were tested in the hydrogenation of several olefins, and were found to have excellent catalytic activity, up to 64,400 hr⁻¹, under standard conditions. A second batch of catalysts was produced by immobilising polymer-stabilised metal colloids onto the supports. Characterisation of the materials showed the polymers and the nanoparticles they contained were associated strongly with the support materials, though the spatial distribution varied significantly between systems. Activation of the catalysts by calcination was shown to initiate their thermal decomposition and oxidation, which in turn affected their catalytic activity. The catalysts containing supported rhodium or platinum were inactive, while those containing supported palladium showed good activity, up to 41,900 hr⁻¹. A third batch of catalysts was produced by immobilising solvent-stabilised metal colloids onto the supports. Amide-type solvents were shown to be the most effective for this purpose,… Advisors/Committee Members: Mucalo, Michael R (advisor), Saunders, Graham C (advisor).

Subjects/Keywords: catalyst; colloid; hydrogenation; nanoparticle

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APA (6^th Edition):

Jaine, J. E. (2016). A Study on Supported Metal Catalysts Prepared from Colloidal Precursors . (Doctoral Dissertation). University of Waikato. Retrieved from http://hdl.handle.net/10289/9981

Chicago Manual of Style (16^th Edition):

Jaine, Jacob Evan. “A Study on Supported Metal Catalysts Prepared from Colloidal Precursors .” 2016. Doctoral Dissertation, University of Waikato. Accessed March 01, 2021. http://hdl.handle.net/10289/9981.

MLA Handbook (7^th Edition):

Jaine, Jacob Evan. “A Study on Supported Metal Catalysts Prepared from Colloidal Precursors .” 2016. Web. 01 Mar 2021.

Vancouver:

Jaine JE. A Study on Supported Metal Catalysts Prepared from Colloidal Precursors . [Internet] [Doctoral dissertation]. University of Waikato; 2016. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/10289/9981.

Council of Science Editors:

Jaine JE. A Study on Supported Metal Catalysts Prepared from Colloidal Precursors . [Doctoral Dissertation]. University of Waikato; 2016. Available from: http://hdl.handle.net/10289/9981

Princeton University

7. Reinhart, Wesley F. Strategies for predicting, understanding, and controlling colloidal crystallization .

Degree: PhD, 2019, Princeton University

URL: http://arks.princeton.edu/ark:/88435/dsp019c67wq63v

► Colloidal crystals continue to draw attention for their applications in photonics, energy conversion, and biosensing, as well as for their usefulness in elucidating questions in… (more)

▼ Colloidal crystals continue to draw attention for their applications in photonics, energy conversion, and biosensing, as well as for their usefulness in elucidating questions in fundamental physics and materials science. However, the wide range of applications for these particles is made possible by the equally wide range of possible self-assembled structures, which may be amorphous or crystalline, close-packed or open, and may include defects with varying morphology and concentration. Experiments, simulations, and theoretical treatments have all shown that this rich phase behavior is enabled by relatively weak interactions between the particles, which leads to small differences in free energy between competing equilibrium and non-equilibrium structures, presenting unique challenges in the fabrication and analysis of the resulting materials. This dissertation explores two complementary topics which both support the goal of engineering advanced materials through directed assembly of colloidal crystals. In the first half of this work, I explore the crystallization of triblock Janus colloids through a variety of simulation methods. I begin by calculating the equilibrium thermodynamic phase diagrams for these particles under a wide variety of conditions, quantifying the driving forces which stabilize each of the competing crystal polymorphs. I next evaluate the crystallization kinetics of several of these solid phases, finding that the different assembly mechanisms of each crystal lattice lead to surprising behaviors. Finally, I demonstrate how a patterned substrate biases the morphology of a crystal film toward large single crystals of a particularly useful polymorph. In the second half, I develop a novel framework for crystal characterization which infers relationships between observed structures automatically rather than relying on pre-programmed templates. I begin by establishing the mathematical basis for this method, showing how my Neighborhood Graph Analysis (NGA) can be used to identify crystal lattices from particle tracking data. Next I extend the framework to binary systems, demonstrating the first-ever automatic characterization of binary superlattices. Finally, I describe a streamlined version of the algorithm which reduces the computational cost by several orders of magnitude, allowing it to be implemented into a fully automated characterization and visualization workflow which is used to investigate a wide variety of crystal lattices. Advisors/Committee Members: Panagiotopoulos, Athanassios Z (advisor).

Subjects/Keywords: colloid; crystal; machine learning

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APA (6^th Edition):

Reinhart, W. F. (2019). Strategies for predicting, understanding, and controlling colloidal crystallization . (Doctoral Dissertation). Princeton University. Retrieved from http://arks.princeton.edu/ark:/88435/dsp019c67wq63v

Chicago Manual of Style (16^th Edition):

Reinhart, Wesley F. “Strategies for predicting, understanding, and controlling colloidal crystallization .” 2019. Doctoral Dissertation, Princeton University. Accessed March 01, 2021. http://arks.princeton.edu/ark:/88435/dsp019c67wq63v.

MLA Handbook (7^th Edition):

Reinhart, Wesley F. “Strategies for predicting, understanding, and controlling colloidal crystallization .” 2019. Web. 01 Mar 2021.

Vancouver:

Reinhart WF. Strategies for predicting, understanding, and controlling colloidal crystallization . [Internet] [Doctoral dissertation]. Princeton University; 2019. [cited 2021 Mar 01]. Available from: http://arks.princeton.edu/ark:/88435/dsp019c67wq63v.

Council of Science Editors:

Reinhart WF. Strategies for predicting, understanding, and controlling colloidal crystallization . [Doctoral Dissertation]. Princeton University; 2019. Available from: http://arks.princeton.edu/ark:/88435/dsp019c67wq63v

Princeton University

8. Landrum, Benjamin Joseph. Structural evolution and rheology of colloidal gels by dynamic simulation .

Degree: PhD, 2015, Princeton University

URL: http://arks.princeton.edu/ark:/88435/dsp01g158bk610

► In this dissertation, we utilize currently large-scale dynamic simulations to examine how colloidal gels evolve over long periods of time, with a goal of increasing… (more)

▼ In this dissertation, we utilize currently large-scale dynamic simulations to examine how colloidal gels evolve over long periods of time, with a goal of increasing our understanding of the stability of gelled products, our main motivation. A major theme in this work is the connection between time-dependent hierarchies of gel structure and time-dependent rheology. First, we demonstrate that structural evolution continues long after gelation in quiescent gels. This evolution is characterized by a growing structural length scale, a feature ubiquitous in phase separating systems. A combination of measurements of particle microstructure, mean-squared displacements, and intermediate scattering functions suggests that domain growth occurs primarily via diffusion of particles along the surface of the particulate network. Second, we examine the consequences of structural evolution on the linear viscoelasticity. In the limit of large frequencies, viscoelastic moduli increase asymptotically with the square root of the frequency, similar to the moduli of dispersions without hydrodynamic interactions. The gels stiffen with age over all frequencies. We observe that the age-dependent moduli are proportional to the growing structural length scale and provide a scaling argument to account for this. Finally, we perturb the gels with step shear stresses to investigate the phenomenon of delayed yield observed in experiments. The computational model recreates experimentally observed phenomena: failure times that decrease rapidly with increasing stress, fluidization under large stresses, and strain stagnation under weak stresses. We observe that all yielding gels yield at a critical strain, approximately 2-3%, but only above a critical stress. However, at intermediate stresses gels not only yield but also re-solidify. Less than 0.1% of the bonds in a colloidal gel need break by the critical strain for macroscopic failure to progress. The re-solidification transition is accompanied by formation of new bonds between broken clusters from the original gel driven together by convection, and the resultant structure is distinct from those of quiescently aged gels. Advisors/Committee Members: Russel, William B (advisor).

Subjects/Keywords: aging; colloid; gel; rheology; simulation

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APA (6^th Edition):

Landrum, B. J. (2015). Structural evolution and rheology of colloidal gels by dynamic simulation . (Doctoral Dissertation). Princeton University. Retrieved from http://arks.princeton.edu/ark:/88435/dsp01g158bk610

Chicago Manual of Style (16^th Edition):

Landrum, Benjamin Joseph. “Structural evolution and rheology of colloidal gels by dynamic simulation .” 2015. Doctoral Dissertation, Princeton University. Accessed March 01, 2021. http://arks.princeton.edu/ark:/88435/dsp01g158bk610.

MLA Handbook (7^th Edition):

Landrum, Benjamin Joseph. “Structural evolution and rheology of colloidal gels by dynamic simulation .” 2015. Web. 01 Mar 2021.

Vancouver:

Landrum BJ. Structural evolution and rheology of colloidal gels by dynamic simulation . [Internet] [Doctoral dissertation]. Princeton University; 2015. [cited 2021 Mar 01]. Available from: http://arks.princeton.edu/ark:/88435/dsp01g158bk610.

Council of Science Editors:

Landrum BJ. Structural evolution and rheology of colloidal gels by dynamic simulation . [Doctoral Dissertation]. Princeton University; 2015. Available from: http://arks.princeton.edu/ark:/88435/dsp01g158bk610

University of Melbourne

9. Balasuriya, Thakshila Sachini. Physical interaction forces in biological soft matter.

Degree: 2012, University of Melbourne

URL: http://hdl.handle.net/11343/37906

► Biological soft matter such as simple proteins to more complex systems such as membranes and cells are composed of a variety of self-assembling units that… (more)

▼ Biological soft matter such as simple proteins to more complex systems such as membranes and cells are composed of a variety of self-assembling units that involve a myriad of dynamic interactions. Understanding the physical interaction forces that occur between simpler biological molecules can give valuable insights to the interactions in whole biological systems in an attempt to manipulate them efficiently. This thesis has examined the direct interaction forces in a series of systems with increasing complexity from well-defined colloidal systems with adsorbed biomolecular coatings, to the interactions in immensely complex living cancer cells. Highly sophisticated sensitive force measurement techniques of Total Internal Reflection Microscopy (TIRM) and Atomic Force Microscopy (AFM) were used to probe these interactions. TIRM was used to measure protein interactions in various electrolyte solutions to determine favorable interactions conducive to protein crystallization at very low concentrations previously unexplored in detail in literature. A fundamental understanding of weak protein interactions is useful for purification of protein mixtures, understanding protein diffusion in concentrated mixtures, and for stabilization of proteins in therapeutic formulations. Trends in protein interactions versus the type of electrolyte comparable to the Hofmeister series were apparent for certain proteins at much lower electrolyte concentrations than observations in literature. Variations in the trends were also seen for other proteins, providing evidence that pure protein interactions are complicated and affected by various factors such as the protein concentration and the surface density, in addition to the salt type and concentration. TIRM proved to be a very promising tool for quantifying pure protein interactions at very low salt concentrations. AFM was used to investigate interaction forces between smart new reversibly switchable biosurfactants to control foam stability. Previous work using AFM on drops and bubbles has demonstrated the importance of surface active molecules in these systems. The principles of such studies were applied to explore biomolecules, such as peptides at deformable interfaces. Direct force measurements showed that the adsorption of proteins was a complex process and the investigation of protein foam stability via air-water interfaces adds complexity to bubble-bubble interactions. The surface forces for very similar proteins were found to be vastly different. This study also highlighted that in general, bubble stability is governed by three key factors: the hydrodynamic drainage behavior of the thin film in between the bubbles, the bubble deformation, and the equilibrium surface forces in the thin film, regardless of the presence of various surfactants at the interface. Direct forces were also investigated in highly complex and poorly characterized biological…

Subjects/Keywords: colloid and surface science

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APA (6^th Edition):

Balasuriya, T. S. (2012). Physical interaction forces in biological soft matter. (Doctoral Dissertation). University of Melbourne. Retrieved from http://hdl.handle.net/11343/37906

Chicago Manual of Style (16^th Edition):

Balasuriya, Thakshila Sachini. “Physical interaction forces in biological soft matter.” 2012. Doctoral Dissertation, University of Melbourne. Accessed March 01, 2021. http://hdl.handle.net/11343/37906.

MLA Handbook (7^th Edition):

Balasuriya, Thakshila Sachini. “Physical interaction forces in biological soft matter.” 2012. Web. 01 Mar 2021.

Vancouver:

Balasuriya TS. Physical interaction forces in biological soft matter. [Internet] [Doctoral dissertation]. University of Melbourne; 2012. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/11343/37906.

Council of Science Editors:

Balasuriya TS. Physical interaction forces in biological soft matter. [Doctoral Dissertation]. University of Melbourne; 2012. Available from: http://hdl.handle.net/11343/37906

Georgia Tech

10. Dunaway, Adam Blake. Characterization of the binding activity of immobilized DNA aptamers for nucleotide and non-nucleotide targets.

Degree: MS, Materials Science and Engineering, 2014, Georgia Tech

URL: http://hdl.handle.net/1853/54310

► Deoxyribonucleic acid (DNA) aptamers are oligonucleotides with high specificity and affinity for non-nucleotide targets ranging from molecular species to cellular proteins. Their high affinity, rapid… (more)

Subjects/Keywords: DNA; Aptamer; Colloid; VEGF; Ampicillin

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APA (6^th Edition):

Dunaway, A. B. (2014). Characterization of the binding activity of immobilized DNA aptamers for nucleotide and non-nucleotide targets. (Masters Thesis). Georgia Tech. Retrieved from http://hdl.handle.net/1853/54310

Chicago Manual of Style (16^th Edition):

Dunaway, Adam Blake. “Characterization of the binding activity of immobilized DNA aptamers for nucleotide and non-nucleotide targets.” 2014. Masters Thesis, Georgia Tech. Accessed March 01, 2021. http://hdl.handle.net/1853/54310.

MLA Handbook (7^th Edition):

Dunaway, Adam Blake. “Characterization of the binding activity of immobilized DNA aptamers for nucleotide and non-nucleotide targets.” 2014. Web. 01 Mar 2021.

Vancouver:

Dunaway AB. Characterization of the binding activity of immobilized DNA aptamers for nucleotide and non-nucleotide targets. [Internet] [Masters thesis]. Georgia Tech; 2014. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/1853/54310.

Council of Science Editors:

Dunaway AB. Characterization of the binding activity of immobilized DNA aptamers for nucleotide and non-nucleotide targets. [Masters Thesis]. Georgia Tech; 2014. Available from: http://hdl.handle.net/1853/54310

University of Canterbury

11. Kokhanenko, Pavlo. Hydrodynamics and chemistry of silica scale formation in hydrogeothermal systems.

Degree: PhD, Mechanical Engineering, 2015, University of Canterbury

URL: http://dx.doi.org/10.26021/3185

► The extraction of geothermal heat can cause precipitation of the minerals dissolved in geothermal fluid. Their deposition on the walls of wells and above-ground plant… (more)

▼ The extraction of geothermal heat can cause precipitation of the minerals dissolved in geothermal fluid. Their deposition on the walls of wells and above-ground plant and in pores near reinjection wells, also known as mineral scaling, is one of the main obstacles to increasing the effectiveness of utilization of the limited geothermal resources. If not controlled properly it can result in accumulation of a significant amount of scale which obstructs pipes and reinjection wells and reduces the efficacy of heat exchangers. The most abundant mineral in geothermal fluid is silica and thus its precipitation can cause the highest scaling rate. While this dissertation is devoted to the study of silica scaling the results obtained may be applicable to other minerals with similar deposition mechanism. Oversaturated silica is known to precipitate from aqueous solution either by the direct chemisorption of single silicic acid molecules (monomers) or by forming colloidal particles suspended in the solution. These particles can subsequently be transported to, and attach onto, a wall. This process of colloidal silica deposition was previously recognised to cause much faster scaling than the direct deposition of silica monomers under typical geothermal plant conditions. While the chemical kinetics of silica polymerization and colloid formation are relatively well understood, transport of these colloids and their stability, which control their aggregation and attachment rates, on the other hand are not. Previous studies of the silica scaling process have identified prominent effects of geothermal brine hydrodynamics on the scaling rate. It was found to increase with the flow rate and particle size, thus suggesting the dominance of the advective (inertial) deposition of colloidal silica. However, this conclusion contradicted the present theory of particle transport in turbulent flows which argues the dominance of the diffusive transport for the relevant range of particle sizes (<1 μm). The development and continuing improvement of the anti-scaling measures required deeper understanding of the complex combination of the phenomena involved in the process of silica scaling. This was pursued in the present study using theoretical and experimental methods. First, the rate of colloidal silica transport from a turbulent flow onto the internal surface of a circular pipe, a cylinder and a flat plate were calculated using available analytical and numerical methods. The obtained theoretical transport rate was found to be about four orders of magnitude higher than the corresponding experimental scaling rate. The latter was determined in the previous studies to be 4.2·10-8 kg/s/m2 for silica colloids of 125 nm in diameter which corresponded to the dimensionless deposition velocity (the dimensionless deposition velocity is the scaling rate normalised by the particle mass concentration and friction velocity) of 1.2·10-6 for the dimensionless particle relaxation time of 2·10-4. Next, based on the standard DLVO…

Subjects/Keywords: geothermal; silica; colloid; transport; deposition

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APA (6^th Edition):

Kokhanenko, P. (2015). Hydrodynamics and chemistry of silica scale formation in hydrogeothermal systems. (Doctoral Dissertation). University of Canterbury. Retrieved from http://dx.doi.org/10.26021/3185

Chicago Manual of Style (16^th Edition):

Kokhanenko, Pavlo. “Hydrodynamics and chemistry of silica scale formation in hydrogeothermal systems.” 2015. Doctoral Dissertation, University of Canterbury. Accessed March 01, 2021. http://dx.doi.org/10.26021/3185.

MLA Handbook (7^th Edition):

Kokhanenko, Pavlo. “Hydrodynamics and chemistry of silica scale formation in hydrogeothermal systems.” 2015. Web. 01 Mar 2021.

Vancouver:

Kokhanenko P. Hydrodynamics and chemistry of silica scale formation in hydrogeothermal systems. [Internet] [Doctoral dissertation]. University of Canterbury; 2015. [cited 2021 Mar 01]. Available from: http://dx.doi.org/10.26021/3185.

Council of Science Editors:

Kokhanenko P. Hydrodynamics and chemistry of silica scale formation in hydrogeothermal systems. [Doctoral Dissertation]. University of Canterbury; 2015. Available from: http://dx.doi.org/10.26021/3185

University of Manchester

12. Sherriff, Nicholas Kevin. Radionuclide dissociation from bentonite colloid systems.

Degree: 2015, University of Manchester

URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:271427

► Deep geological disposal is a method of managing high level, long-‐lived nuclear waste. It is a concept that many countries are exploring for the possibility… (more)

▼ Deep geological disposal is a method of managing high level, long-‐lived nuclear waste. It is a concept that many countries are exploring for the possibility of managing nuclear waste generated from power production. For deep geological disposal to be viable then areas where problems may surface have to be explored. Bentonite clay has been proposed as the material to be used for the backfill of the repositories. Its swelling properties ensure that it will expand to plug the bore holes that will be made for the waste, its impermeable nature restricts contact between groundwater and the waste package and its stability on a geological timescale all make it desirable as a backfill material. This project looks at the role that colloids formed from the bentonite clay could have in facilitating radionuclide transport away from a nuclear waste repository. Several radionuclides (Eu(III), U(VI), Th(IV) and Am(III)) have been considered in this research, and information from these studies will be used in the BELBaR project’s outputs, which will eventually support a disposal safety case.Ternary systems of 152Eu(III), bulk bentonite and EDTA ([Eu] = 7.9 x 10-‐10 M; pH = 6.0 – 7.0) have been studied. Without EDTA, there was slow uptake in a two-‐stage process, with initial rapid sorption of Eu(III) (96%), followed by slower uptake of a smaller fraction (3.0 % over a period of 1 month). The reversibility of Eu(III) binding was tested by allowing Eu(III) to sorb to bentonite for 1 – 322 days. EDTA was added to the pre-‐equilibrated Eu bentonite systems at 0.01 M. A dissociation rate constant of approximately 4.3 x 10-‐8 s-‐1 (values in the range 2.2 x 10-‐8 – 1.0 x 10-‐7 s-‐1) for pre-‐equilibration times ≥ 7 days was measured. Eventually, the amount of Eu(III) remaining bound to the bentonite was within error of that when EDTA was also present prior to contact (4.5 % ± 0.6). Eu interactions with colloidal bentonite were studied, and the dissociation rate constant measured by a resin competition method. A dissociation rate of 8.8 x 10-‐7 s-‐1 and a range of 7.7 x 10-‐7 – 9.5 x 10-‐7 s-‐1 were measured. For both bulk and colloidal bentonite slow dissociation was observed for Eu(III), but there was no evidence for ‘irreversible’ binding.The interactions of 232U(VI) with bentonite colloids ([U] = 5.43 x 10-‐10 M; pH = 8.8 ± 0.2) have been studied using a resin ion exchange competition technique. The reversibility of the interaction was studied by allowing U(VI) to sorb to bentonite colloids for periods from 1 – 35 days. A fraction of the U(VI) was removed from the solution instantaneously (28-‐50 %), and after 3 days, the amount of U(VI) remaining on the bentonite colloids was 17-‐ 25%. With time, the amount of U(VI) retained by the bentonite colloid is reduced further, with a first order dissociation rate constant of 5.6 x 10-‐7 s-‐1. Whilst the dissociating fraction was small (24% (+34; -‐12 %)), complete dissociation was not observed. Although slow dissociation was observed for U(VI), there was no convincing… Advisors/Committee Members: MORRIS, KATHERINE K, Livens, Francis, Morris, Katherine.

Subjects/Keywords: bentonite; colloid; dissociation; radionuclide; kinetics

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APA (6^th Edition):

Sherriff, N. K. (2015). Radionuclide dissociation from bentonite colloid systems. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:271427

Chicago Manual of Style (16^th Edition):

Sherriff, Nicholas Kevin. “Radionuclide dissociation from bentonite colloid systems.” 2015. Doctoral Dissertation, University of Manchester. Accessed March 01, 2021. http://www.manchester.ac.uk/escholar/uk-ac-man-scw:271427.

MLA Handbook (7^th Edition):

Sherriff, Nicholas Kevin. “Radionuclide dissociation from bentonite colloid systems.” 2015. Web. 01 Mar 2021.

Vancouver:

Sherriff NK. Radionuclide dissociation from bentonite colloid systems. [Internet] [Doctoral dissertation]. University of Manchester; 2015. [cited 2021 Mar 01]. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:271427.

Council of Science Editors:

Sherriff NK. Radionuclide dissociation from bentonite colloid systems. [Doctoral Dissertation]. University of Manchester; 2015. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:271427

Harvard University

13. Yoon, Kisun. Synthesis and Applications of Non-spherical Dimer Colloids.

Degree: PhD, Applied Physics, 2012, Harvard University

URL: http://nrs.harvard.edu/urn-3:HUL.InstRepos:9767979

►

Colloids are promising building blocks in material synthesis because of their controllability of size and surface properties. The synthesis of chemically and/or geometrically anisotropic colloidal… (more)

▼

Colloids are promising building blocks in material synthesis because of their controllability of size and surface properties. The synthesis of chemically and/or geometrically anisotropic colloidal particles has received attentions with the expectation of building blocks for complex structures. However, the synthesis of anisotropic colloidal particles is by far more difficult than the synthesis of spherical colloidal particles. Lack of monodispersity and productivity of many anisotropic particles often limits their applications as a building block for complex structures. Thus, it is highly desirable to develop methods which can produce a large amount of monodisperse non-spherical particles with controllable asymmetric surface properties. This dissertation details the work for developing such a method. The major result of this dissertation is a synthetic method to produce monodisperse non-spherical colloids with anisotropic surface property in a large quantity. The anisotropic colloid, which we call it as Dimer particle, has two fused lobes like a dumbbell and each lobe’s size can be independently controlled. We present a novel method to synthesize sub-micron size Dimer particles. This method can produce a large amount of submicron-sized Dimer particles with good monodispersity and well-controlled shape. Submicron-sized Dimer particles have been highly desired since they can be used as a building block for self assembly using Brownian motion, colloidal surfactant for Pickering emulsion, and photonic materials. To fully take advantage of the anisotropy of the particles, we develop a facile method to tailor the surface property of each lobe independently by asymmetrically coating the particles with gold nanoparticles. This method doesn’t need the arrangement of particles onto any type of interfaces. Asymmetric coating of gold nanoparticles can be carried out simply by mixing Dimer particles with gold nanoparticles. The formation mechanism of the submicron-sized Dimer particles is explained with evidences. Finally, we illustrate that Dimer particles show rich phase behavior under electric fields and explain the behavior by considering various interactions involved in the system. Our investigation shows that electric field can effectively control the orientation and assembled structure of Dimer particles. In conclusion, these asymmetrically functionalized Dimer particles are promising building blocks to generate suprastructures that will be useful in photonic, electronic and diagnostic applications.

Engineering and Applied Sciences

Advisors/Committee Members: Weitz, David A. (advisor), Spaepen, Frans (committee member), Auguste, Debra (committee member).

Subjects/Keywords: materials science; anisotropic colloid; colloid; polymerization; self assembly

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APA (6^th Edition):

Yoon, K. (2012). Synthesis and Applications of Non-spherical Dimer Colloids. (Doctoral Dissertation). Harvard University. Retrieved from http://nrs.harvard.edu/urn-3:HUL.InstRepos:9767979

Chicago Manual of Style (16^th Edition):

Yoon, Kisun. “Synthesis and Applications of Non-spherical Dimer Colloids.” 2012. Doctoral Dissertation, Harvard University. Accessed March 01, 2021. http://nrs.harvard.edu/urn-3:HUL.InstRepos:9767979.

MLA Handbook (7^th Edition):

Yoon, Kisun. “Synthesis and Applications of Non-spherical Dimer Colloids.” 2012. Web. 01 Mar 2021.

Vancouver:

Yoon K. Synthesis and Applications of Non-spherical Dimer Colloids. [Internet] [Doctoral dissertation]. Harvard University; 2012. [cited 2021 Mar 01]. Available from: http://nrs.harvard.edu/urn-3:HUL.InstRepos:9767979.

Council of Science Editors:

Yoon K. Synthesis and Applications of Non-spherical Dimer Colloids. [Doctoral Dissertation]. Harvard University; 2012. Available from: http://nrs.harvard.edu/urn-3:HUL.InstRepos:9767979

University of Louisville

14. Work, Andrew Hardesty. Electrokinetic colloid patterning characterization with a scanning laser.

Degree: M. Eng., 2012, University of Louisville

URL: 10.18297/etd/1593 ; https://ir.library.louisville.edu/etd/1593

► Rapid Electrokinetic Patterning (REP) is a relatively new method for collecting and manipulating micrometer-scale particles at an electrode surface. REP is an AC electrokinetic technique… (more)

▼ Rapid Electrokinetic Patterning (REP) is a relatively new method for collecting and manipulating micrometer-scale particles at an electrode surface. REP is an AC electrokinetic technique that uses induced fluid motion to capture and manipulate particles. A laser (975 nm) is focused on the surface of the parallel-plate electrode, generating a thermal gradient in the medium. This thermal gradient is acted upon by the AC electric field in such manner as to produce a vortex. Particles are trapped on the electrode surface at the center of the vortex. It is hypothesized that AC electroosmotic flows act to hold the particles to the electrode surface more strongly than other holding forces, such as dielectrophoresis (DEP). The accumulation of single-size particles occurs in one layer, and is two-dimensional in REP, and crystalline in nature under the correct conditions. Electrostatic forces separate the particles while fluid drag forces tend to corral the particles together. The particle aggregations tend to exhibit several exclusive, characteristic behaviors: the particles will group together very closely and uniformly, the particles will form arbitrary aggregations of tightly packed particles, or the particles will exhibit a nearly-random spacing. Parameters are varied such that the average spacing is changed between the particles to transition the particles from nearly-random spacing to a uniform, tightly packed crystalline grid. The relationship between the drag forces and the electrostatic forces parallel to the electrode surface are explored for different AC frequencies, AC voltages, laser powers, laser scan rates, and laser scan lengths. The effect these parameters have on the spacing of the particles is characterized, and aggregation crystallinity is discussed. A more detailed force analysis is discussed for non-varying parameters with a dot-shaped aggregation. The ability to use this force analysis for particle spectroscopy is briefly discussed. Particle motion was analyzed with Particle Tracking Velocimetry (PTV) using Matlab scripts. Advisors/Committee Members: Williams, Stuart J., 1981-.

Subjects/Keywords: Colloid; Colloid characterization; Patterning; Laser; Rapid electrokinetic patterning

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APA (6^th Edition):

Work, A. H. (2012). Electrokinetic colloid patterning characterization with a scanning laser. (Masters Thesis). University of Louisville. Retrieved from 10.18297/etd/1593 ; https://ir.library.louisville.edu/etd/1593

Chicago Manual of Style (16^th Edition):

Work, Andrew Hardesty. “Electrokinetic colloid patterning characterization with a scanning laser.” 2012. Masters Thesis, University of Louisville. Accessed March 01, 2021. 10.18297/etd/1593 ; https://ir.library.louisville.edu/etd/1593.

MLA Handbook (7^th Edition):

Work, Andrew Hardesty. “Electrokinetic colloid patterning characterization with a scanning laser.” 2012. Web. 01 Mar 2021.

Vancouver:

Work AH. Electrokinetic colloid patterning characterization with a scanning laser. [Internet] [Masters thesis]. University of Louisville; 2012. [cited 2021 Mar 01]. Available from: 10.18297/etd/1593 ; https://ir.library.louisville.edu/etd/1593.

Council of Science Editors:

Work AH. Electrokinetic colloid patterning characterization with a scanning laser. [Masters Thesis]. University of Louisville; 2012. Available from: 10.18297/etd/1593 ; https://ir.library.louisville.edu/etd/1593

Rochester Institute of Technology

15. Dunning, Peter David. Controlling the Transient Interface Shape and Deposition Profile Left by Desiccation of Colloidal Droplets on Multiple Polymer Surfaces.

Degree: MS, Mechanical Engineering, 2015, Rochester Institute of Technology

URL: https://scholarworks.rit.edu/theses/8788

► A colloidal suspension is a small constituent of insoluble solid particles suspended in a liquid medium. Control over the wetting, evaporation, and deposition patterns… (more)

▼ A colloidal suspension is a small constituent of insoluble solid particles suspended in a liquid medium. Control over the wetting, evaporation, and deposition patterns left by colloidal suspensions is valuable in many biological, medical, industrial, and agricultural applications. Understanding the governing principles of wetting and evaporative phenomena of these colloidal suspensions may lead to greater control over resultant deposition patterns. Perhaps the most familiar pattern forms when an initially heterogeneous colloidal suspension leaves a dark ring pattern at the edge of a drop. This pattern is referred to as a coffee-stain and it can be seen from dried droplets of spilled coffee. This coffee-stain effect was first investigated by Deegan et. al. who discovered that these patterns occur when outward radial flows driven by evaporation at the triple contact line dominate over other effects. While the presence of coffee-stain patterns is undesirable in many printing and medical diagnostic processes, it can also be advantageous in the production of low cost transparent conductive films, the deposition of metal vapor, and the manipulation of biological structures. Controlling the interactions between the substrate, liquid, vapor, and particles can lead to control over the size and morphology of evaporative deposition patterns left by aqueous colloidal suspensions. Several methods have been developed to control the evaporation of colloidal suspensions to either suppress or enhance the coffee stain effect. Electrowetting on Dielectric (EWOD) is one promising method that has been used to control colloidal depositions by applying either an AC or DC electric field. EWOD actuation has the potential to dynamically control colloidal deposition left by desiccated droplets to either suppress or enhance the coffee stain effect. It may also allow for independent control of the fluidic interface and deposition of particles via electrowetting and electrokinetic forces. Implementation of this technique requires that the colloidal droplet be separated from the active electrode by a dielectric layer to prevent electrolysis. A variety of polymer layers have been used in EWOD devices for a variety of applications. In applications that involve desiccation of colloidal suspensions, the material for this layer should be chosen carefully as it can play an important role in the resulting deposition pattern. An experimental method to monitor the transient evolution of the shape of an evaporating colloidal droplet and optically quantify the resultant deposition pattern is presented. Unactuated colloidal suspensions will be desiccated on a variety of substrates commonly used in EWOD applications. Transient image profiles and particle deposition patterns are examined for droplets containing fluorescent micro-particles. Qualitative and quantitative comparisons of these results will be used to compare multiple different cases in an effort to provide insight into the effects of polymer selection on the drying dynamics and… Advisors/Committee Members: Michael Schertzer.

Subjects/Keywords: Colloid; Desiccation; Electrowetting; Evaporation; EWOD; Polymer

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APA (6^th Edition):

Dunning, P. D. (2015). Controlling the Transient Interface Shape and Deposition Profile Left by Desiccation of Colloidal Droplets on Multiple Polymer Surfaces. (Masters Thesis). Rochester Institute of Technology. Retrieved from https://scholarworks.rit.edu/theses/8788

Chicago Manual of Style (16^th Edition):

Dunning, Peter David. “Controlling the Transient Interface Shape and Deposition Profile Left by Desiccation of Colloidal Droplets on Multiple Polymer Surfaces.” 2015. Masters Thesis, Rochester Institute of Technology. Accessed March 01, 2021. https://scholarworks.rit.edu/theses/8788.

MLA Handbook (7^th Edition):

Dunning, Peter David. “Controlling the Transient Interface Shape and Deposition Profile Left by Desiccation of Colloidal Droplets on Multiple Polymer Surfaces.” 2015. Web. 01 Mar 2021.

Vancouver:

Dunning PD. Controlling the Transient Interface Shape and Deposition Profile Left by Desiccation of Colloidal Droplets on Multiple Polymer Surfaces. [Internet] [Masters thesis]. Rochester Institute of Technology; 2015. [cited 2021 Mar 01]. Available from: https://scholarworks.rit.edu/theses/8788.

Council of Science Editors:

Dunning PD. Controlling the Transient Interface Shape and Deposition Profile Left by Desiccation of Colloidal Droplets on Multiple Polymer Surfaces. [Masters Thesis]. Rochester Institute of Technology; 2015. Available from: https://scholarworks.rit.edu/theses/8788

University of Utah

16. Pazmino, Eddy Fernando. Development of a new colloid filtration theory in the presence of energy barriers via discrete nanoscale heterogeneity.

Degree: PhD, Geology & Geophysics, 2015, University of Utah

URL: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3874/rec/701

► Traditional colloidal filtration theory (CFT) predicts zero attachment when repulsion exists between colloid and filtering media (collector). Notably, repulsion is prevalent in environmental systems, e.g.,… (more)

▼ Traditional colloidal filtration theory (CFT) predicts zero attachment when repulsion exists between colloid and filtering media (collector). Notably, repulsion is prevalent in environmental systems, e.g., riverbank filtration, and is manifested as energy barriers to attachment due to electro osmotic interactions between surfaces of the same charge. A mechanistic particle trajectory model that incorporates discrete nanoscale attractive zones (heterodomains) to account for attachment under bulk repulsive colloid-collector interactions was developed and tested against an array of direct observation experiments conducted in an impinging jet system. Retention of 0.25 to 1.95 �m colloids on soda-lime glass slides was examined for 6 and 20 mM ionic strengths (IS) and average jet velocities of 1.7x10-3 to 5.94x10-3 ms-1 (equivalent pore water velocity of 1.9 and 8.2 mday-1, respectively) in order to characterize the heterodomain size distribution and surface coverage. Simulations indicate that a power law distribution of 60 and 120 nm radii heterodomains (4:1 number ratio) and 0.04% surface coverage is able to quantitatively capture observed retention across all conditions examined. Furthermore, the same heterogeneity characteristics were able to capture qualitative trends of release of colloids deposited in contact with heterodomains in response to perturbations in flow and IS relative to the loading condition, i.e., factor 25 increase in jet velocity or factor 20 decrease in IS. Finally, a correlation equation was developed to incorporate the mechanistic basis provided from the discrete heterogeneity model and calibrated from the array of experiments. The equation is a function of the colloidal number, which captures the main characteristics of the energy barrier, and the fraction of colloids that persist in the near surface fluid domain (secondary minimum) obtained from a Maxwell distribution of kinetic energies. Notably, the proposed correlation equation captures scores of experiments reported in the literature for a broad range of conditions for colloid sizes ranging from 0.06 to 3.1 �m, IS from 0.1 to 300 mM, and average pore water velocities from 4 to 588 mday-1on soda-lime glass beads. The main coefficient of the correlation equation is a linear function heterodomain surface coverage, indicating that different coefficients may capture filtration across different aquifer-relevant minerals.

Subjects/Keywords: Colloid Transport; Environmental Conditions; Filtration Theory; Heterogeneity

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APA (6^th Edition):

Pazmino, E. F. (2015). Development of a new colloid filtration theory in the presence of energy barriers via discrete nanoscale heterogeneity. (Doctoral Dissertation). University of Utah. Retrieved from http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3874/rec/701

Chicago Manual of Style (16^th Edition):

Pazmino, Eddy Fernando. “Development of a new colloid filtration theory in the presence of energy barriers via discrete nanoscale heterogeneity.” 2015. Doctoral Dissertation, University of Utah. Accessed March 01, 2021. http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3874/rec/701.

MLA Handbook (7^th Edition):

Pazmino, Eddy Fernando. “Development of a new colloid filtration theory in the presence of energy barriers via discrete nanoscale heterogeneity.” 2015. Web. 01 Mar 2021.

Vancouver:

Pazmino EF. Development of a new colloid filtration theory in the presence of energy barriers via discrete nanoscale heterogeneity. [Internet] [Doctoral dissertation]. University of Utah; 2015. [cited 2021 Mar 01]. Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3874/rec/701.

Council of Science Editors:

Pazmino EF. Development of a new colloid filtration theory in the presence of energy barriers via discrete nanoscale heterogeneity. [Doctoral Dissertation]. University of Utah; 2015. Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3874/rec/701

University of Tasmania

17. Lee, RA. The stability of wood resin colloids in paper manufacture.

Degree: 2012, University of Tasmania

URL: https://eprints.utas.edu.au/14702/10/Lee_whole_thesis_ex_pub_mat.pdf ; https://eprints.utas.edu.au/14702/3/whole-lee-thesis-inc-pub-mat.pdf

► Within the pulp and paper industry, the recycling of water to reduce water consumption leads to accumulation of colloidal material in the process water and… (more)

▼ Within the pulp and paper industry, the recycling of water to reduce water consumption leads to accumulation of colloidal material in the process water and greater risk of deposition. Resinous materials, arising from the wood extractives released during papermaking, form colloidal particles in solution that agglomerate and deposit onto the different surfaces within the mill. The formation of the resinous deposits, known as pitch, can be detrimental to the paper quality, process control and efficiency. A major factor in the colloidal stability of these substances is the presence of natural polymers originating from the wood and salts that accumulate in the process water as a result of increased system closure. To date, most work has looked at the stability of northern hemisphere woods. The work of this thesis explores the stability and formation of southern hemisphere Pinus radiata wood resins through the application of novel techniques. It investigates the factors that affect the stability of wood extractive colloids under varying conditions of ionic strength, ionic valency, shear, temperatures, pH, and mixtures of cations and wood polymers released from Pinus radiata thermomechanical pulp. Electron paramagnetic resonance (EPR) was used to study model wood extractive colloids. Nitroxides were chosen as EPR probes to gain a greater understanding of the different interior vs. surrounding parts of the colloidal droplet in order to assess current proposed models of the structure of the wood extractive colloid. Additionally, salt was added to solution in order to understand the macroscopic environmental interactions that the colloid experiences. A revised model for the colloid structure has been proposed to better explain the behaviour of the wood extractive colloids. Through the use of the photometric dispersion analyser (PDA), the coagulation kinetics for wood resins were determined. The coagulation kinetics allowed the stability factor (W) for the addition of various concentrations of salt to be determined with variation in a number of supernatant physiochemical factors (salt type, valency, temperature, pH, shear and simultaneous addition of multiple salts). Coagulation of a colloidal wood extractive solution by a single salt was found to follow the Schultz-Hardy rule, with the critical coagulation concentration (CCC) for a salt strongly influenced by salt valency (z). Addition of trivalent salts indicates that the affinity of aluminium and iron salts for the colloidal wood resin surface is greater than their affinity for hydrating water molecules. Changes in temperature and pH of an aqueous colloid suspension were observed to affect the concentration of salt required to destabilise the colloid, as expected from DLVO theory. An increase of the supernatant’s pH resulted in an increase in the CCC for calcium. An increase in temperature resulted in an increased CCC for all salts tested. The degree of variation in CCC with temperature was found to be valency dependant. The stability of the colloidal wood resins was…

Subjects/Keywords: colloid; coagulation; stability; salt; hemicellulose deposition

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APA (6^th Edition):

Lee, R. (2012). The stability of wood resin colloids in paper manufacture. (Thesis). University of Tasmania. Retrieved from https://eprints.utas.edu.au/14702/10/Lee_whole_thesis_ex_pub_mat.pdf ; https://eprints.utas.edu.au/14702/3/whole-lee-thesis-inc-pub-mat.pdf

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Lee, RA. “The stability of wood resin colloids in paper manufacture.” 2012. Thesis, University of Tasmania. Accessed March 01, 2021. https://eprints.utas.edu.au/14702/10/Lee_whole_thesis_ex_pub_mat.pdf ; https://eprints.utas.edu.au/14702/3/whole-lee-thesis-inc-pub-mat.pdf.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Lee, RA. “The stability of wood resin colloids in paper manufacture.” 2012. Web. 01 Mar 2021.

Vancouver:

Lee R. The stability of wood resin colloids in paper manufacture. [Internet] [Thesis]. University of Tasmania; 2012. [cited 2021 Mar 01]. Available from: https://eprints.utas.edu.au/14702/10/Lee_whole_thesis_ex_pub_mat.pdf ; https://eprints.utas.edu.au/14702/3/whole-lee-thesis-inc-pub-mat.pdf.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Lee R. The stability of wood resin colloids in paper manufacture. [Thesis]. University of Tasmania; 2012. Available from: https://eprints.utas.edu.au/14702/10/Lee_whole_thesis_ex_pub_mat.pdf ; https://eprints.utas.edu.au/14702/3/whole-lee-thesis-inc-pub-mat.pdf

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Cornell University

18. Cakmak, Mehmet. Computational Fluid Flow And Transport Of Colloidal Particles In Soil Pores.

Degree: PhD, Agricultural and Biological Engineering, 2011, Cornell University

URL: http://hdl.handle.net/1813/33577

► Transport of colloidal size particulate matter is of special interest of environmental studies because colloids and adsorbed chemicals can be transported over long distances. Colloid… (more)

▼ Transport of colloidal size particulate matter is of special interest of environmental studies because colloids and adsorbed chemicals can be transported over long distances. Colloid facilitated transport can pose potentially high risk for pollution of ground water. Visualizations of colloid transport using bright field and confocal microscopes have discovered interesting phenomena such colloids moving in circles that cannot be described by the traditional Darcy scale models. That is why computational pore scale models are needed to better understand colloid transport and fate in porous media. Transport and fate of colloids depend largely on flow field in the pores and it is, therefore, important to simulate the flow field while taking grain surface properties into account. The aim of this dissertation is hence to determine the flow fields in realistic pores by solving the incompressible Navier-Stokes equation with a powerful commercial available finite element program COMSOL Multiphysics. The dissertation has five chapters. In the first chapter a short introduction is given. In the second chapter the COMSOL Multiphysics program is tested by revisiting the classical colloid filtration theory on colloid retention on a spherical sand grain. Retention of colloids on grains simulated with COMSOL is found to be similar to semi-analytical solutions previously published. Subsequently colloid retention on an air bubble is simulated and greater colloid retention is calculated than on a soil grain due to the slip boundary condition at the Air-Water interface which creates higher velocities and more fluid flow around air bubble resulting in greater amounts of colloids that can diffuse to the interface. In the third chapter the effect of surface roughness on hydrodynamics of colloid transport in a saturated porous media is investigated by simulating the flow fields around perfectly smooth, smoothed, and naturally rough sand grains. The results show that micron scale surface asperities of rough grains create greater vorticity and more stagnant flow regions compared to smooth grains likely resulting in greater colloid retention for the rough grains. In the fourth chapter the dependence of dynamic contact angle between the interface of two immiscible fluids and solid surface on the interface velocity is simulated in an empty capillary channel to provide a new understanding on the formation of unstable wetting fronts in coarse or water repellent soils. The results show an increase in contact angle when the velocity of the front increases, which is consistent with experimental studies in the literature. In the fifth chapter the problems encountered during the research and future directions are briefly explained. Advisors/Committee Members: Steenhuis, Tammo S (chair), Hay, Anthony G. (committee member), Parlange, Jean-Yves (committee member).

Subjects/Keywords: Colloid Transport; Hydrodynamics; Dynamic Contact Angle

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APA (6^th Edition):

Cakmak, M. (2011). Computational Fluid Flow And Transport Of Colloidal Particles In Soil Pores. (Doctoral Dissertation). Cornell University. Retrieved from http://hdl.handle.net/1813/33577

Chicago Manual of Style (16^th Edition):

Cakmak, Mehmet. “Computational Fluid Flow And Transport Of Colloidal Particles In Soil Pores.” 2011. Doctoral Dissertation, Cornell University. Accessed March 01, 2021. http://hdl.handle.net/1813/33577.

MLA Handbook (7^th Edition):

Cakmak, Mehmet. “Computational Fluid Flow And Transport Of Colloidal Particles In Soil Pores.” 2011. Web. 01 Mar 2021.

Vancouver:

Cakmak M. Computational Fluid Flow And Transport Of Colloidal Particles In Soil Pores. [Internet] [Doctoral dissertation]. Cornell University; 2011. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/1813/33577.

Council of Science Editors:

Cakmak M. Computational Fluid Flow And Transport Of Colloidal Particles In Soil Pores. [Doctoral Dissertation]. Cornell University; 2011. Available from: http://hdl.handle.net/1813/33577

Vanderbilt University

19. McNew, Coy Phillip. The Attachment of Colloidal Particles to Environmentally Relevant Surfaces: Effect of Ionic Strength, Particle Shape, and Physicochemical Properties.

Degree: PhD, Environmental Engineering, 2015, Vanderbilt University

URL: http://hdl.handle.net/1803/15082

► The sharp increase in production of engineered nanomaterials (ENMs) combined with their high potential for aquatic toxicity, mean that understanding the transport of these materials… (more)

▼ The sharp increase in production of engineered nanomaterials (ENMs) combined with their high potential for aquatic toxicity, mean that understanding the transport of these materials throughout the environment is of utmost importance. In the presence of environmentally relevant surfaces, the relationship between particle attachment and relevant variables was quantitatively investigated and reported. Increasing temperature greatly altered the attachment onto two different humic substances by altering the hydration, and therefore confirmation, of the natural organic matter (NOM) matrix. By increasing the hydration of the NOM layer, the matrix swelled, allowing for more surface area for particle attachment and an increase in possible sorption sites. Similarly, high ionic strengths caused the NOM layer to condense, reducing surface area and sorption sites for particle attachment and effectively lowering particle attachment efficiency. The shape of the particle itself also played a role in attachment. A humic acid layer showed preference to smaller, more spherical particles due to the size of the voids within the layer, raising attachment efficiency for the smaller, spherical particles only, while a smoother, more condensed layer did not. As ionic strength increased, however, the layer condensed and the preference vanished. Finally, a predictive model for attachment efficiency was developed using a machine learning approach and trained on a database containing all the data gathered in this work combined with all currently available, relevant attachment efficiency literature. The model employed 13 training features, each of which was a physicochemical characteristic of the particle, surface, or solution system, to predict attachment efficiency with relatively high performance. The most important features for predicting attachment efficiency were also identified. The results presented in this work improve the understanding of particle attachment efficiency by identifying important variables, explaining why these variables have an effect on attachment efficiency, and also providing an empirical predictive model for attachment efficiency. By applying this approach to other areas of particle transport, we can close the gap between experimental and modeling efforts, advancing transport knowledge as quickly and efficiently as possible. Only by closing this gap can we expect to understand particle transport in a system as complex as the natural environment. Advisors/Committee Members: Yusong Li (committee member), Alan Bowers (committee member), M. Douglas LeVan (committee member), George Hornberger (committee member), Eugene J. LeBoeuf (Committee Chair).

Subjects/Keywords: transport; nanoparticle; nanomaterial; colloid; QCM; machine learning

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APA (6^th Edition):

McNew, C. P. (2015). The Attachment of Colloidal Particles to Environmentally Relevant Surfaces: Effect of Ionic Strength, Particle Shape, and Physicochemical Properties. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/15082

Chicago Manual of Style (16^th Edition):

McNew, Coy Phillip. “The Attachment of Colloidal Particles to Environmentally Relevant Surfaces: Effect of Ionic Strength, Particle Shape, and Physicochemical Properties.” 2015. Doctoral Dissertation, Vanderbilt University. Accessed March 01, 2021. http://hdl.handle.net/1803/15082.

MLA Handbook (7^th Edition):

McNew, Coy Phillip. “The Attachment of Colloidal Particles to Environmentally Relevant Surfaces: Effect of Ionic Strength, Particle Shape, and Physicochemical Properties.” 2015. Web. 01 Mar 2021.

Vancouver:

McNew CP. The Attachment of Colloidal Particles to Environmentally Relevant Surfaces: Effect of Ionic Strength, Particle Shape, and Physicochemical Properties. [Internet] [Doctoral dissertation]. Vanderbilt University; 2015. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/1803/15082.

Council of Science Editors:

McNew CP. The Attachment of Colloidal Particles to Environmentally Relevant Surfaces: Effect of Ionic Strength, Particle Shape, and Physicochemical Properties. [Doctoral Dissertation]. Vanderbilt University; 2015. Available from: http://hdl.handle.net/1803/15082

Texas A&M University

20. Hammons, Jessica Lynn. Role of Acidity in Mobilizing Colloidal Particulate Matter From Natural Sand Grain Surface.

Degree: MS, Biological and Agricultural Engineering, 2012, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10627

► Mobilization of colloidal particulate matter (most important, clay particles) from a soil matrix in the subsurface environment is an important environmental process. As many contaminants… (more)

Subjects/Keywords: Colloid Mobilization; Acidity; HCl; Contaminant transport

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APA (6^th Edition):

Hammons, J. L. (2012). Role of Acidity in Mobilizing Colloidal Particulate Matter From Natural Sand Grain Surface. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10627

Chicago Manual of Style (16^th Edition):

Hammons, Jessica Lynn. “Role of Acidity in Mobilizing Colloidal Particulate Matter From Natural Sand Grain Surface.” 2012. Masters Thesis, Texas A&M University. Accessed March 01, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10627.

MLA Handbook (7^th Edition):

Hammons, Jessica Lynn. “Role of Acidity in Mobilizing Colloidal Particulate Matter From Natural Sand Grain Surface.” 2012. Web. 01 Mar 2021.

Vancouver:

Hammons JL. Role of Acidity in Mobilizing Colloidal Particulate Matter From Natural Sand Grain Surface. [Internet] [Masters thesis]. Texas A&M University; 2012. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10627.

Council of Science Editors:

Hammons JL. Role of Acidity in Mobilizing Colloidal Particulate Matter From Natural Sand Grain Surface. [Masters Thesis]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10627

Penn State University

21. das, sambeeta. Designs for Directing Motion at Nano and Microscale.

Degree: 2016, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/8w32r560x

► Motion is one of the defining characteristics of life. Inspired by the biological motors at the micron and nanoscale, scientists have developed artificial machines that… (more)

▼ Motion is one of the defining characteristics of life. Inspired by the biological motors at the micron and nanoscale, scientists have developed artificial machines that self propel in solutions and are on the same length scale as biological motors. However, motion at such low length scales is fraught with many challenges. The focus of this thesis is on devising some field free and autonomous strategies for addressing those challenges. This dissertation starts with a literature review of the field with a discussion about the various self-propelled prevalent in the scientific community. Then the different challenges of motion at low Reynolds number and their applicability to the motors are discussed. One of the more popular categories of catalytic micromotors is Janus motors which move in a solution of hydrogen peroxide due to the catalytic activity of Platinum. However it is very hard to introduce directionality in these motors due to the Brownian randomizations prevalent in low Reynolds number regime. The first chapter of this thesis introduces a method of overcoming this challenge by exploiting the interaction of Janus micromotors with physical features. It was observed that Janus micromotors could move linearly in geometric "tracks" as long as they have fuel available for their motion, thus overcoming Brownian diffusion rotations. The second system discussed here takes its inspiration from biological motors and is based on cilia and flagella seen in microorganisms. A design for synthesizing artificial cilia is outlined. This system consists of polymeric rods with a catalytic disk on top which undergo oscillations due to reversible chemical reactions. These synthetic ciliary systems represent an efficient way of mixing fluid at the microscale and overcome the challenges associated with laminar flow at such regimes. The discussion then moves to the nanoscale with the introduction of enzyme nanomotors in Chapter 4. Enzyme molecules not only show enhanced diffusion in the presence of their substrate such as urea for Urease or hydrogen peroxide for catalase; but they also show chemotactic behavior towards their substrate gradient. This is directly parallel to the chemotactic behavior shown by bacteria. This property is exploited to design a system of separating two enzymes with the same mass and isoelectric point. The separation is observed within a two-inlet, five-outlet microfluidic network, designed to allow mixtures of active (ones that catalyze substrate turnover) and inactive (ones that do not catalyze substrate turnover) enzymes, labeled with different fluorophores, to flow through one of the inlets. Substrate solution prepared in phosphate buffer was introduced through the other inlet of the device at the same flow rate. In the presence of a substrate concentration gradient, active enzyme molecules migrated preferentially toward the substrate channel leading to separation of the enzymes. As discussed above enzyme molecules undergo enhanced diffusion in the presence of their substrate. Additionally immobilizing… Advisors/Committee Members: Ayusman Sen, Dissertation Advisor/Co-Advisor, Ayusman Sen, Committee Chair/Co-Chair, Thomas E Mallouk, Committee Member, John V Badding, Committee Member, Darrell Velegol, Outside Member.

Subjects/Keywords: Micromotor; nanomotor; Active Matter; colloid; Enzymes

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APA (6^th Edition):

das, s. (2016). Designs for Directing Motion at Nano and Microscale. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/8w32r560x

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

das, sambeeta. “Designs for Directing Motion at Nano and Microscale.” 2016. Thesis, Penn State University. Accessed March 01, 2021. https://submit-etda.libraries.psu.edu/catalog/8w32r560x.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

das, sambeeta. “Designs for Directing Motion at Nano and Microscale.” 2016. Web. 01 Mar 2021.

Vancouver:

das s. Designs for Directing Motion at Nano and Microscale. [Internet] [Thesis]. Penn State University; 2016. [cited 2021 Mar 01]. Available from: https://submit-etda.libraries.psu.edu/catalog/8w32r560x.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

das s. Designs for Directing Motion at Nano and Microscale. [Thesis]. Penn State University; 2016. Available from: https://submit-etda.libraries.psu.edu/catalog/8w32r560x

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Wollongong

22. Müller, Marc Benjamin. Chemically Converted Graphene Dispersions and Graphene Films.

Degree: PhD, Department of Chemistry, 2011, University of Wollongong

URL: ; https://ro.uow.edu.au/theses/3364

► The formation of graphene dispersions and its subsequent characterisation form the basis of this thesis. A range of experimental techniques were employed for this… (more)

▼ The formation of graphene dispersions and its subsequent characterisation form the basis of this thesis. A range of experimental techniques were employed for this characterisation, namely atomic force microscopy (AFM), contact angle and conductivity measurements, UV-visible spectroscopy, Fourier transform infrared spectroscopy (FT-IR), elemental analysis, pH-zetapotential, acid-base titration, and capillary zone electrophoresis (CZE). Various fabrication techniques such as layer-by-layer self-assembly and vacuum filtration were used to create thin transparent, conducting films as well as micron thick conducting paper. Graphene dispersions were created by oxidising graphite, exfoliating graphite oxide to graphene oxide (GO) via sonication, and reducing it to chemically converted graphene (CCG) with hydrazine. CCG has been shown to be a negatively charged colloid. To avoid aggregation on reduction of GO to CCG, the hydrazine to GO mass ratio was optimised to 7:10. CZE was performed to investigate the electrokinetic behaviour of colloidal CCG in comparison to GO. The different amount of charge carrying functional groups were reflected in the slower electrophoretic mobility obtained for the CCG in comparison to the GO. CCG and GO paper were produced via vacuum-filtration of CCG and GO dispersions. The conductivity of CCG paper increased almost linearly with increasing thermal annealing temperature to a maximum 351 S/cm. A Youngs modulus and tensile strength of 41.8 GPa and 293.3 MPa respectively could be obtained. Thin films of anionic CCG were produced by self-assembly with the cationic polymers polyethylenimine (PEI), poly(diallyldimethylammonium chloride) (PDDA), poly-L-lysine hydrobromide (PLL) or chitosan (CHIT). Up to 20 bilayers of PEI-CCG could be self-assembled with full CCG coverage per layer. The sheet resistance for a single PEI-CCG bilayer was (29.6 +/- 8.4) MOhm/square and the absorbance at 270 nm between 0.2 and 0.5. Raman spectroscopy of self-assembled CCG, GO and thermally annealed (500°C, 1 h in argon) CCG and GO films showed a lowering in G to D peak ratio for CCG films. Annealed films showed a higher G to D peak ratio than non-annealed films. The electrochemical electron transfer properties at self-assembled PEI-CCG films were tested using potassium ferri /ferrocyanide. Reversible electron transfer chararcteristics were observed. Lastly the cytocompatiblity of PEI-CCG films was investigated. Cytocompatibility on neural, muscle, and fibroblastic cells was observed using live cell phase contrast imaging and lactate dehydrogenase (LDH) assays.

Subjects/Keywords: IPRI; colloid; graphene; materials science; self-assembly

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APA (6^th Edition):

Müller, M. B. (2011). Chemically Converted Graphene Dispersions and Graphene Films. (Doctoral Dissertation). University of Wollongong. Retrieved from ; https://ro.uow.edu.au/theses/3364

Chicago Manual of Style (16^th Edition):

Müller, Marc Benjamin. “Chemically Converted Graphene Dispersions and Graphene Films.” 2011. Doctoral Dissertation, University of Wollongong. Accessed March 01, 2021. ; https://ro.uow.edu.au/theses/3364.

MLA Handbook (7^th Edition):

Müller, Marc Benjamin. “Chemically Converted Graphene Dispersions and Graphene Films.” 2011. Web. 01 Mar 2021.

Vancouver:

Müller MB. Chemically Converted Graphene Dispersions and Graphene Films. [Internet] [Doctoral dissertation]. University of Wollongong; 2011. [cited 2021 Mar 01]. Available from: ; https://ro.uow.edu.au/theses/3364.

Council of Science Editors:

Müller MB. Chemically Converted Graphene Dispersions and Graphene Films. [Doctoral Dissertation]. University of Wollongong; 2011. Available from: ; https://ro.uow.edu.au/theses/3364

University College London (University of London)

23. Knott, Michael. Phases and phase transitions in charged colloidal suspensions.

Degree: PhD, 2001, University College London (University of London)

URL: https://discovery.ucl.ac.uk/id/eprint/10099736/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270941

► We study the stability and phase behaviour of charged colloidal suspensions theoretically, starting from fundamental thermodynamics and electrostatics. The linearised Poisson-Boltzmann equation is solved, subject… (more)

▼ We study the stability and phase behaviour of charged colloidal suspensions theoretically, starting from fundamental thermodynamics and electrostatics. The linearised Poisson-Boltzmann equation is solved, subject to justifiable approximations, for a suspension containing a large number of identical spherical macroions under conditions of constant surface charge. The electrostatic term in the Helmholtz free energy is cohesive, and this is opposed by a repulsive counterion ideal gas term. We argue that the stability and phase behaviour of a charged colloidal suspension result from competition between these two terms in the free energy, and that the DLVO theory is inappropriate for the description of these phenomena. In a system containing no added salt, a van der Waals loop can appear in the pV diagram, indicating phase coexistence between phases with different macroion densities. This occurs when the ratio of the macroion charge to the macroion radius is greater than a critical value. Theoretical phase diagrams for systems containing salt show phase separation when the macroion charge is high and the salt concentration is low, in agreement with experimental results. Calculation of the partition of salt between coexisting phases having different macroion densities reveals a 'reverse Donnan effect': at sufficiently high values of the macroion charge and mean salt concentration, the salt is densest in the macroion-rich region. We show that phase coexistence persists when the macroion charge is allowed to vary, using a simple model for the ion dissociation at the surfaces of the macroions. The square gradient approximation is used to calculate the surface tension between two colloidal phases of differing density, and the results are compared with evidence from various colloidal systems. The nucleation rate of a colloidal liquid cluster from a metastable colloidal gas is estimated using a version of classical nucleation theory. We explain the recently described 'Swiss Cheese effect' in terms of nucleation phenomena, and argue that it shows evidence both of homogeneous and of heterogeneous nucleation. Metastability is likely to be very important in colloidal systems, and therefore the consideration of nucleation rates is essential to the study of phase behaviour in such systems.

Subjects/Keywords: 541; Colloid chemistry

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APA (6^th Edition):

Knott, M. (2001). Phases and phase transitions in charged colloidal suspensions. (Doctoral Dissertation). University College London (University of London). Retrieved from https://discovery.ucl.ac.uk/id/eprint/10099736/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270941

Chicago Manual of Style (16^th Edition):

Knott, Michael. “Phases and phase transitions in charged colloidal suspensions.” 2001. Doctoral Dissertation, University College London (University of London). Accessed March 01, 2021. https://discovery.ucl.ac.uk/id/eprint/10099736/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270941.

MLA Handbook (7^th Edition):

Knott, Michael. “Phases and phase transitions in charged colloidal suspensions.” 2001. Web. 01 Mar 2021.

Vancouver:

Knott M. Phases and phase transitions in charged colloidal suspensions. [Internet] [Doctoral dissertation]. University College London (University of London); 2001. [cited 2021 Mar 01]. Available from: https://discovery.ucl.ac.uk/id/eprint/10099736/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270941.

Council of Science Editors:

Knott M. Phases and phase transitions in charged colloidal suspensions. [Doctoral Dissertation]. University College London (University of London); 2001. Available from: https://discovery.ucl.ac.uk/id/eprint/10099736/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270941

University of Surrey

24. Humby, Steven John. Modelling of flow and colloids in porous media.

Degree: PhD, 1999, University of Surrey

URL: http://epubs.surrey.ac.uk/844200/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298043

► Porous media and transport within them play technically important roles in many of our industries. However, classical mean field engineering descriptions used to model the… (more)

▼ Porous media and transport within them play technically important roles in many of our industries. However, classical mean field engineering descriptions used to model the complex interactions between the porous medium and the fluids and colloids within it are not completely satisfactory. The design capability of the engineering community would be greatly enhanced if these models could be more clearly linked to the mesoscopic details of the fluid/suspension/porous solid systems. This would allow cheaper, yet quicker, and more innovative design and optimization of systems involving fluid/suspension flow in porous media. Modern techniques for the explicit mesoscopic modelling of porous media, and fluid and colloid transport within them, have developed to a point where their combination in a single simulation tool can be contemplated. However, at present, no such tool exists. The aim of this study was to design and test a comprehensive simulation tool that could accurately model the transport phenomena of any given fluid and colloidal system within any given porous medium at a mesoscopic level. Lattice gas automata (LGA) modelling techniques for fluid and colloid transport, and the Joshi/Quiblier/Adler (JQA) statistical method for reconstructing porous media, were uniquely combined to achieve this. The results of simulations were compared to measurements obtained using an experimental apparatus. The objectives of the study were to: 1) determine a priori the permeability of porous media, and; 2) simulate deposition phenomena observed experimentally. The study showed that permeabilities predicted using the simulation tool were lower than those determined experimentally. Several causes for this were identified, all of which can be addressed in the short-term. Simulated changes in fluid velocity and particle concentration were found to alter the rate and pattern of deposition in a manner consistent with experimental results. Furthermore, the tool provided a rich description of fundamental physical phenomena at the pore scale level. These preliminary findings indicate that the combination of these models provide the basis for further development leading to a mesoscopic modelling tool capable of predicting fluid and colloid transport in porous media.

Subjects/Keywords: 660; Colloid transport

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APA (6^th Edition):

Humby, S. J. (1999). Modelling of flow and colloids in porous media. (Doctoral Dissertation). University of Surrey. Retrieved from http://epubs.surrey.ac.uk/844200/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298043

Chicago Manual of Style (16^th Edition):

Humby, Steven John. “Modelling of flow and colloids in porous media.” 1999. Doctoral Dissertation, University of Surrey. Accessed March 01, 2021. http://epubs.surrey.ac.uk/844200/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298043.

MLA Handbook (7^th Edition):

Humby, Steven John. “Modelling of flow and colloids in porous media.” 1999. Web. 01 Mar 2021.

Vancouver:

Humby SJ. Modelling of flow and colloids in porous media. [Internet] [Doctoral dissertation]. University of Surrey; 1999. [cited 2021 Mar 01]. Available from: http://epubs.surrey.ac.uk/844200/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298043.

Council of Science Editors:

Humby SJ. Modelling of flow and colloids in porous media. [Doctoral Dissertation]. University of Surrey; 1999. Available from: http://epubs.surrey.ac.uk/844200/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298043

University of Manchester

25. Sherriff, Nicholas Kevin. Radionuclide dissociation from bentonite colloid systems.

Degree: PhD, 2015, University of Manchester

URL: https://www.research.manchester.ac.uk/portal/en/theses/radionuclide-dissociation-from-bentonite-colloid-systems(43918efc-26e4-4e41-a450-3e209c20340d).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.666868

► Deep geological disposal is a method of managing high level, long-‐lived nuclear waste. It is a concept that many countries are exploring for the possibility… (more)

▼ Deep geological disposal is a method of managing high level, long-‐lived nuclear waste. It is a concept that many countries are exploring for the possibility of managing nuclear waste generated from power production. For deep geological disposal to be viable then areas where problems may surface have to be explored. Bentonite clay has been proposed as the material to be used for the backfill of the repositories. Its swelling properties ensure that it will expand to plug the bore holes that will be made for the waste, its impermeable nature restricts contact between groundwater and the waste package and its stability on a geological timescale all make it desirable as a backfill material. This project looks at the role that colloids formed from the bentonite clay could have in facilitating radionuclide transport away from a nuclear waste repository. Several radionuclides (Eu(III), U(VI), Th(IV) and Am(III)) have been considered in this research, and information from these studies will be used in the BELBaR project’s outputs, which will eventually support a disposal safety case. Ternary systems of 152Eu(III), bulk bentonite and EDTA ([Eu] = 7.9 x 10-‐10 M; pH = 6.0 – 7.0) have been studied. Without EDTA, there was slow uptake in a two-‐stage process, with initial rapid sorption of Eu(III) (96%), followed by slower uptake of a smaller fraction (3.0 % over a period of 1 month). The reversibility of Eu(III) binding was tested by allowing Eu(III) to sorb to bentonite for 1 – 322 days. EDTA was added to the pre-‐equilibrated Eu bentonite systems at 0.01 M. A dissociation rate constant of approximately 4.3 x 10-‐8 s-‐1 (values in the range 2.2 x 10-‐8 – 1.0 x 10-‐7 s-‐1) for pre-‐equilibration times ≥ 7 days was measured. Eventually, the amount of Eu(III) remaining bound to the bentonite was within error of that when EDTA was also present prior to contact (4.5 % ± 0.6). Eu interactions with colloidal bentonite were studied, and the dissociation rate constant measured by a resin competition method. A dissociation rate of 8.8 x 10-‐7 s-‐1 and a range of 7.7 x 10-‐7 – 9.5 x 10-‐7 s-‐1 were measured. For both bulk and colloidal bentonite slow dissociation was observed for Eu(III), but there was no evidence for ‘irreversible’ binding. The interactions of 232U(VI) with bentonite colloids ([U] = 5.43 x 10-‐10 M; pH = 8.8 ± 0.2) have been studied using a resin ion exchange competition technique. The reversibility of the interaction was studied by allowing U(VI) to sorb to bentonite colloids for periods from 1 – 35 days. A fraction of the U(VI) was removed from the solution instantaneously (28-‐50 %), and after 3 days, the amount of U(VI) remaining on the bentonite colloids was 17-‐ 25%. With time, the amount of U(VI) retained by the bentonite colloid is reduced further, with a first order dissociation rate constant of 5.6 x 10-‐7 s-‐1. Whilst the dissociating fraction was small (24% (+34; -‐12 %)), complete dissociation was not observed. Although slow dissociation was observed for U(VI), there was no convincing…

Subjects/Keywords: 541; bentonite; colloid; dissociation; radionuclide; kinetics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Sherriff, N. K. (2015). Radionuclide dissociation from bentonite colloid systems. (Doctoral Dissertation). University of Manchester. Retrieved from https://www.research.manchester.ac.uk/portal/en/theses/radionuclide-dissociation-from-bentonite-colloid-systems(43918efc-26e4-4e41-a450-3e209c20340d).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.666868

Chicago Manual of Style (16^th Edition):

Sherriff, Nicholas Kevin. “Radionuclide dissociation from bentonite colloid systems.” 2015. Doctoral Dissertation, University of Manchester. Accessed March 01, 2021. https://www.research.manchester.ac.uk/portal/en/theses/radionuclide-dissociation-from-bentonite-colloid-systems(43918efc-26e4-4e41-a450-3e209c20340d).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.666868.

MLA Handbook (7^th Edition):

Sherriff, Nicholas Kevin. “Radionuclide dissociation from bentonite colloid systems.” 2015. Web. 01 Mar 2021.

Vancouver:

Sherriff NK. Radionuclide dissociation from bentonite colloid systems. [Internet] [Doctoral dissertation]. University of Manchester; 2015. [cited 2021 Mar 01]. Available from: https://www.research.manchester.ac.uk/portal/en/theses/radionuclide-dissociation-from-bentonite-colloid-systems(43918efc-26e4-4e41-a450-3e209c20340d).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.666868.

Council of Science Editors:

Sherriff NK. Radionuclide dissociation from bentonite colloid systems. [Doctoral Dissertation]. University of Manchester; 2015. Available from: https://www.research.manchester.ac.uk/portal/en/theses/radionuclide-dissociation-from-bentonite-colloid-systems(43918efc-26e4-4e41-a450-3e209c20340d).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.666868

University of Bristol

26. Shafiq, M. Electrostatic interactions of non-polar colloidal system and implications for industrial applications.

Degree: PhD, 2019, University of Bristol

URL: http://hdl.handle.net/1983/865ecb40-6459-469c-ba1e-3c194be32de0

► Colloidal science is vital in many industrial processes due to its outstanding properties, viability and versatility to tailor numerous industrial applications such as formulations in… (more)

▼ Colloidal science is vital in many industrial processes due to its outstanding properties, viability and versatility to tailor numerous industrial applications such as formulations in food and beauty products, decorative layering and painting as well as ink and electronic printing. Hence, the stability of a colloidal system is an important key to determine the final properties of the colloidal-based products. The stability of colloids by electrostatic means in a fluid is outlined by the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory and the behaviour of colloids in the non-aqueous system is still uncertain despite its' importance in industrial applications. The main objective of this thesis is primarily to investigate the electrostatic interactions, mainly between colloidal particles in non-aqueous systems which can be applied to industrial needs such as printing and coating. We generate controllable micrometer-range electrostatic interactions in a suspension by using a charge control additive (the surfactant, dioctyl sodium sulfosuccinate [AOT]), and an organic salt, tetradodecylammonium tetrakis (3,5-bis (trifluoromethyl)phenyl)borate (TDAT) in non-aqueous solvents. Both systems adapted different mechanisms of altering the electrostatic interaction between PMMA colloids. For AOT system, the particle surface charge is modified by adsorption of charged and neutral AOT micelles on the surface, hence affecting the interactions between particles. For the electrolytic TDAT non-aqueous system, the screening length of the solution was altered due to the presence of free ions in the solution. This is confirmed by the conductivity and theoretical Debye length values. However, from force measurement using the blinking optical tweezers (BOT), we found out that the measured screening length shows a non-monotonic dependence on the TDAT concentration. The deviation between these values revealed that at high TDAT concentrations, the classical DLVO theory is no longer valid for the system. We postulate that the formation of Janus-like particles due to charge instability resulted from the non-uniform charge distribution on the colloidal surfaces. This is preliminarily confirmed by the rotation of a PMMA colloids chain when an electric field is applied. In a later series, the electrostatic interactions between charged PMMA colloids were investigated in an ionic liquid solution. The correlation between the number of ions in solution and the screening length was reported and the usual trend observed. The particle attraction was observed in all systems, which leads to the formation of colloidal clusters and aggregates. At high ionic liquid concentrations, we discovered that the colloidal stabilization is achieved and this may be due to the decaying particle aggregation rate, driven by the enhanced viscosity of the solution. We relate the formation of clusters and aggregates formed in the bulk system with the deposition patterns of a colloidal droplet on a hydrophobically-coated glass substrate. The drying of droplets containing…

Subjects/Keywords: 540; Evaporation; Colloid; Electrostatic; Charge; Polymer

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Shafiq, M. (2019). Electrostatic interactions of non-polar colloidal system and implications for industrial applications. (Doctoral Dissertation). University of Bristol. Retrieved from http://hdl.handle.net/1983/865ecb40-6459-469c-ba1e-3c194be32de0

Chicago Manual of Style (16^th Edition):

Shafiq, M. “Electrostatic interactions of non-polar colloidal system and implications for industrial applications.” 2019. Doctoral Dissertation, University of Bristol. Accessed March 01, 2021. http://hdl.handle.net/1983/865ecb40-6459-469c-ba1e-3c194be32de0.

MLA Handbook (7^th Edition):

Shafiq, M. “Electrostatic interactions of non-polar colloidal system and implications for industrial applications.” 2019. Web. 01 Mar 2021.

Vancouver:

Shafiq M. Electrostatic interactions of non-polar colloidal system and implications for industrial applications. [Internet] [Doctoral dissertation]. University of Bristol; 2019. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/1983/865ecb40-6459-469c-ba1e-3c194be32de0.

Council of Science Editors:

Shafiq M. Electrostatic interactions of non-polar colloidal system and implications for industrial applications. [Doctoral Dissertation]. University of Bristol; 2019. Available from: http://hdl.handle.net/1983/865ecb40-6459-469c-ba1e-3c194be32de0

Boston University

27. Yu, Jin. Developing superparamagnetic nanoparticle (SPION) systems with tunable colloidal stability and magnetic properties.

Degree: PhD, Materials Science & Engineering, 2020, Boston University

URL: http://hdl.handle.net/2144/41041

► SPIONs have unique material properties: ultra-small size and high magnetic susceptibility. These properties give SPIONs advantages to be used in a wide range of applications… (more)

Subjects/Keywords: Materials science; Cell separation; Colloid; Lipid

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Yu, J. (2020). Developing superparamagnetic nanoparticle (SPION) systems with tunable colloidal stability and magnetic properties. (Doctoral Dissertation). Boston University. Retrieved from http://hdl.handle.net/2144/41041

Chicago Manual of Style (16^th Edition):

Yu, Jin. “Developing superparamagnetic nanoparticle (SPION) systems with tunable colloidal stability and magnetic properties.” 2020. Doctoral Dissertation, Boston University. Accessed March 01, 2021. http://hdl.handle.net/2144/41041.

MLA Handbook (7^th Edition):

Yu, Jin. “Developing superparamagnetic nanoparticle (SPION) systems with tunable colloidal stability and magnetic properties.” 2020. Web. 01 Mar 2021.

Vancouver:

Yu J. Developing superparamagnetic nanoparticle (SPION) systems with tunable colloidal stability and magnetic properties. [Internet] [Doctoral dissertation]. Boston University; 2020. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/2144/41041.

Council of Science Editors:

Yu J. Developing superparamagnetic nanoparticle (SPION) systems with tunable colloidal stability and magnetic properties. [Doctoral Dissertation]. Boston University; 2020. Available from: http://hdl.handle.net/2144/41041

University of Pennsylvania

28. Yao, Lu. Capillary Assembly of Anisotropic Particles.

Degree: 2014, University of Pennsylvania

URL: https://repository.upenn.edu/edissertations/1509

► My research is in the field of interfacial phenomena. Since all materials are bounded by surfaces or interfaces, the ability to manipulate or tune interfacial… (more)

Subjects/Keywords: Anisotropic; Assembly; Capillary; Colloid; Particle; Chemical Engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Yao, L. (2014). Capillary Assembly of Anisotropic Particles. (Thesis). University of Pennsylvania. Retrieved from https://repository.upenn.edu/edissertations/1509

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Yao, Lu. “Capillary Assembly of Anisotropic Particles.” 2014. Thesis, University of Pennsylvania. Accessed March 01, 2021. https://repository.upenn.edu/edissertations/1509.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Yao, Lu. “Capillary Assembly of Anisotropic Particles.” 2014. Web. 01 Mar 2021.

Vancouver:

Yao L. Capillary Assembly of Anisotropic Particles. [Internet] [Thesis]. University of Pennsylvania; 2014. [cited 2021 Mar 01]. Available from: https://repository.upenn.edu/edissertations/1509.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Yao L. Capillary Assembly of Anisotropic Particles. [Thesis]. University of Pennsylvania; 2014. Available from: https://repository.upenn.edu/edissertations/1509

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Georgia Tech

29. Yarlagadda, Sri Charan. Dynamics of hard and soft colloids in confined geometries and on structured surfaces.

Degree: PhD, Chemical and Biomolecular Engineering, 2015, Georgia Tech

URL: http://hdl.handle.net/1853/53888

► We investigated the depletion interactions of colloids and hindrance behavior of hard and soft colloidal particles near neighboring walls. We first used numerical modeling to… (more)

Subjects/Keywords: Colloid; Diffusion; Hindrance; Soft matter; Emulsions; Microgels

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Yarlagadda, S. C. (2015). Dynamics of hard and soft colloids in confined geometries and on structured surfaces. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/53888

Chicago Manual of Style (16^th Edition):

Yarlagadda, Sri Charan. “Dynamics of hard and soft colloids in confined geometries and on structured surfaces.” 2015. Doctoral Dissertation, Georgia Tech. Accessed March 01, 2021. http://hdl.handle.net/1853/53888.

MLA Handbook (7^th Edition):

Yarlagadda, Sri Charan. “Dynamics of hard and soft colloids in confined geometries and on structured surfaces.” 2015. Web. 01 Mar 2021.

Vancouver:

Yarlagadda SC. Dynamics of hard and soft colloids in confined geometries and on structured surfaces. [Internet] [Doctoral dissertation]. Georgia Tech; 2015. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/1853/53888.

Council of Science Editors:

Yarlagadda SC. Dynamics of hard and soft colloids in confined geometries and on structured surfaces. [Doctoral Dissertation]. Georgia Tech; 2015. Available from: http://hdl.handle.net/1853/53888

University of Edinburgh

30. Reeves, Matthew. Structure, dynamics and the role of particle size in bicontinuous Pickering emulsions.

Degree: PhD, 2016, University of Edinburgh

URL: http://hdl.handle.net/1842/23641

► Bicontinuous Pickering emulsions (or bijels) are a relatively new class of novel soft material with many potential industrial applications, including microfluidics, tissue engineering and catalysis.… (more)

▼ Bicontinuous Pickering emulsions (or bijels) are a relatively new class of novel soft material with many potential industrial applications, including microfluidics, tissue engineering and catalysis. They are typically formed by initiating the spinodal decomposition of a binary liquid mixture in the presence of neutrally-wetting colloidal particles. The particles attach at the liquid-liquid interface and arrest the phase separation by jamming when the concentration of particles approaches the 2D close-packing limit. Predicted by simulations in 2005 and realized in the laboratory in 2007, many aspects of the bijels complex behaviour and properties have remained unexplored. This thesis expands the knowledge of the bijels structural and dynamical properties, while focusing specifically on the role of particle size. The bijels porosity (average interfacial separation L) according to simulations can be controlled by varying the size r and volume fraction ϕ of particles in the system (L ∝ r/ϕ). The inverse scaling of L with ϕ has been verified for one size of particle, but to access smaller values of L (to allow the structure to be used for a wider range of industrial applications) the scaling with r must be tested. Chapter 3 presents the first systematic study of reducing particle size in bijels made with the liquid pair water/lutidine (W/L).We find that a five-fold reduction in r only requires moderate modification to preparation methods (concentrations of reactants during particle synthesis and increased particle sonication time) and in principle allows L values of between 1 & 10 μm to be accessed in the W/L system, where previously 10 μm was the limit. We demonstrate that this reduced lower bound of L can be translated into a lower bound for polymerized bijels also. Unfortunately, reducing particle size even further (in the same way) reveals a law of diminishing returns, as the uptake fraction of particles to the interface also reduces as we reduce particle size. Hence, to reduce lengthscale even further, a new bijel fabrication paradigm is required. Unexpectedly, we find that the temperature quench rate becomes less important for smaller particles (which constitutes a direct material synthesis advantage) and develop a new theoretical framework to take account of this observation. Large particles promote domain pinch-off during the coarsening (due to a larger driving force towards spontaneous curvature) resulting in bijel failure when slow rates are used because the time required to jam is greater than the time required for depercolation. To further probe the bijels structure as a function of particle size and quench rate, and to account for the success/failure scenarios which seem not to depend on L, in Chapter 4 we quantitatively characterize the morphology by measuring distributions of interfacial curvatures. By computing area-averaged quantities to make valid comparisons, we find that smaller particles and faster quench rates produce bijels with greater hyperbolic `open' character, aligning with our understanding of…

Subjects/Keywords: 620.1; bijels; Pickering emulsions; colloid; wetting; jamming

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Reeves, M. (2016). Structure, dynamics and the role of particle size in bicontinuous Pickering emulsions. (Doctoral Dissertation). University of Edinburgh. Retrieved from http://hdl.handle.net/1842/23641

Chicago Manual of Style (16^th Edition):

Reeves, Matthew. “Structure, dynamics and the role of particle size in bicontinuous Pickering emulsions.” 2016. Doctoral Dissertation, University of Edinburgh. Accessed March 01, 2021. http://hdl.handle.net/1842/23641.

MLA Handbook (7^th Edition):

Reeves, Matthew. “Structure, dynamics and the role of particle size in bicontinuous Pickering emulsions.” 2016. Web. 01 Mar 2021.

Vancouver:

Reeves M. Structure, dynamics and the role of particle size in bicontinuous Pickering emulsions. [Internet] [Doctoral dissertation]. University of Edinburgh; 2016. [cited 2021 Mar 01]. Available from: http://hdl.handle.net/1842/23641.

Council of Science Editors:

Reeves M. Structure, dynamics and the role of particle size in bicontinuous Pickering emulsions. [Doctoral Dissertation]. University of Edinburgh; 2016. Available from: http://hdl.handle.net/1842/23641

Open Access Theses and Dissertations