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目前，膠體粒子在眾多領域扮演著越來重要的角色，例如工業中油漆流變特性的修飾以及在醫藥靶向藥物釋放等。通過改變膠體粒子間的相互作用 ，可以設計得到適合不同需要的穩定的流體、凝膠和晶體 。而開拓膠體粒子廣泛用途的 前提是對於膠體粒子穩定性的充分理解， 因此，對溶液中粒子間的相互作用的研究很有必要 。 / 本文主要討論了兩個問題 ，均圍繞如何利用小體積膠粒子改變大體積粒子間相互作用 。第一部分 ，我們研究二元粒子懸浮液中膠體粒間的相互作用。結果顯示，帶電納米粒子的加入可以改變帶電納米粒子與平面間的相互作用。當以上三者均輕微帶電，即使在很低的濃度下， 納米粒子也會發生沉積，並導致表面間靜電排斥作用的增強 。而對於高度帶電的納米粒子， 微米粒子和平面 ，納米粒子的吸附將受到阻礙，但實驗結果顯示，此時納米粒子仍能夠引導微與平引導微與平面間的額外斥力。此現象違反傳統高電系統中小體積粒子通常引導排空引力的認知。我們認為此現象可能來源於納米粒子被困於平面附近的區域時引導的排斥力 。 在相互排斥的微米粒子及納體系中 ，這個結果是對納米光暈增強的第一個研究 ，並對利用帶電納米粒子調節二元體系穩定性的傳統方法提出挑戰。 / 在本文的第二部分，我們將對二元帶電粒子相互作用的研究擴展到流體介面。 我們系統研究了二元膠體粒子分別在油水介面和空氣上的相互作用。我們利用高分辨亮場顯微鏡和粒子追蹤方法對受限膠體粒子間的相互作用進行研究。結果顯示 ，偶極 -偶極排斥作用在油水介面和空氣上的行為一致。介面膠體粒子間的相互作用主要包括兩個方面，一是對水相電解質敏感的偶極-偶極排斥作用，二是油相中殘餘電荷的靜電排斥作用 。另外，我們的結果顯示在介面上小體積粒子的加入可以導致二維排空引力，使得大體積粒子相互靠近。與溶液中不同的是，這個二維排空引力能夠在很低濃度時發生。 相信這個結果可以鼓勵更多理論方面的研究，從而對解決有關結晶，擠阻及相轉變等基礎問題提供幫助 。 / Colloidal particies are playing an increasingly important role in a wide range of applications, from rheological modifiers in the paint industry to nanoparticies for targeted drug delivery. By altering interactions between colloidal particies, one can design stable fluids, gels or crystals needed for different purposes. Prior to exploit of a widespread application for colloidal particies, a good understanding of the stability of particies suspension and thus of the interaction between particies in aqueous suspension, are required. / In this thesis two major topics are addressed, and both of them are connected with the use of smaller particies to manipulate the interaction force between larger particies. In the first part of this thesis, I have performed an experimental investigation on the interparticie interaction in a binary particie suspension. The results show that the initial addition of charged nanoparticies can alter the interaction force between charged microparticie and plate surface. When the nanoparticie, microparticie and plate were slightly charged, sufficient nanoparticie deposition on plate occurred, leading to an increased electrostatic repulsion between the surfaces even at low nanoparticie concentration. When the nanoparticies, microparticie and plate were highly charged, the adsorption of nanoparticies onto plate/particie surfaces was hindered. Surprisingly, the addition of nanoparticies also produced a repulsive force. This observed trend is substantially different from the conventional highly charged systems where the addition of nanoparticies creates an attractive depletion force between the microparticie and plate. Our results suggest that these nanoparticies might reside to the region near the plate surface, which eventually give rise to the effective repulsive force. This is the first study to demonstrate that nanoparticie halos can also arise in binary systems of mutually but highly repulsive microparticie/nanoparticie dispersions. We believe that this finding will stimulate theoretians to investigate the nature of such induced interparticie interactions. Our study thus highlights the challenges associated with using charged nanoparticles as a tool to regulate stability in the binary particle systems. / In the second part of this thesis, we extend our study of using smaller charged colloidal particles to alter the interaction force between larger colloidal particles at the fluid-fluid interfaces. We systemically study the binary mixture of colloidal particles at both oil/water and air/water interface. We focus on resolving the interaction forces between confined colloidal particles by using a combination of high tempo-spatial resolution optical microscopy and particle tracking algorithm. Our results show that dipolar-dipolar repulsive force is consistently presented at the both air/water and oil/water systems. The interaction force between charged particles trapped at the fluid interfaces may contain two parts: the dipole-dipole repulsion which is sensitive to the electrolyte content of the water phase, and the electrostatic repulsion arised from the presence of a very small amount of residual electric charge at the particle-oil interface that is insensitive to the electrolyte content of the water phase. Moreover, our results show that the addition of small particle can lead to a 2D depletion attraction, pushing the large particles closer at the interface. Unlike in bulk solution, this depletion force occurs even at very low depletant concentration because there is no need of depletants to reside above and below the larger particles when they are confined at the interfaces. We believe this kind of 2D depletion interaction will stimulate more theoretical simulations in order to provide an insight for answering fundamental questions concerning with crystallization, jamming and other phase transitions. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Xing, Xiaochen. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references. / Abstract also in Chinese. / Chapter 1. --- Interaction of Colloidal Particles in Bulk Solution --- p.1 / Chapter 1.1. --- Interparticle Forces --- p.1 / Chapter 1.1.1. --- Steric Stabilization and Bridging Interaction --- p.1 / Chapter 1.1.2. --- Electrostatic Stabilization --- p.2 / Chapter 1.1.3. --- Depletion Interaction --- p.4 / Chapter 1.1.4. --- Haloing Stabilization --- p.7 / Chapter 1.2. --- Surface Force Measurement Techniques --- p.10 / Chapter 1.3. --- Total Internal Reflection Microscope (TIRM) --- p.12 / Chapter 1.3.1. --- The Technique and Principle --- p.12 / Chapter 1.3.2. --- Measuring the Potentials --- p.18 / Chapter 1.4. --- References and Notes --- p.22 / Chapter 2. --- Direct Measurement of Interaction Forces in Bidispersed Particle Suspension Systems --- p.25 / Chapter 2.1. --- Introduction --- p.25 / Chapter 2.2. --- Interaction Forces in the Bidispersed Systems --- p.28 / Chapter 2.2.1. --- Direct Measurement of the Interaction Forces between Colloidal Particles in a Solution of PS Nanoparticles. --- p.28 / Chapter 2.2.1.1. --- Materials and Methods Materials and Methods Materials and Methods Materials and MethodsMaterials and Methods Materials and Methods --- p.29 / Chapter 2.2.1.2. --- Results Results --- p.32 / Chapter 2.2.1.3. --- Discussion Discussion --- p.41 / Chapter 2.2.2. --- Direct Measurement of the Interaction Forces between Colloidal Particles in a Solution of PS-co-NIPAm Nanoparticles --- p.45 / Chapter 2.3. --- Conclusion --- p.52 / Chapter 2.4. --- References and Notes --- p.54 / Chapter 3. --- Colloidal Particles at Liquid/Liquid Interface --- p.56 / Chapter 3.1. --- Introduction --- p.56 / Chapter 3.2. --- Interactions Forces between Colloidal Particles at Interface --- p.59 / Chapter 3.2.1. --- Repulsive Interactions --- p.63 / Chapter 3.2.2. --- Attractive Interactions --- p.74 / Chapter 3.2.3. --- Force Measurements of Interfacial Particles --- p.79 / Chapter 3.3. --- References and Notes --- p.82 / Chapter 4. --- Direct Measurement of Interaction Force between Colloidal Particles at Fluid Interfaces --- p.88 / Chapter 4.1. --- Materials and Method --- p.90 / Chapter 4.1.1. --- Apparatus and Sample Preparation --- p.90 / Chapter 4.1.2. --- Image processing --- p.92 / Chapter 4.1.3. --- Pair Distribution Function (PDF) and Radial Distribution Function (RDF) --- p.92 / Chapter 4.1.4. --- Pair-Potential of Particle Ensembles --- p.96 / Chapter 4.2. --- Interactions of Particles at Oil (Air)/Water Interface --- p.97 / Chapter 4.2.1. --- Interactions of Monodispersed Colloidal Particles at Oil (Air)/Water Interface --- p.97 / Chapter 4.2.2. --- Effect of Adding Salt on the Interparticle Interaction at Oil(Air)/Water Interface --- p.104 / Chapter 4.2.3. --- Interaction of Binary Particles at Oil/Water Interface --- p.108 / Chapter 4.2.4. --- Effect of Adding Salt on the Binary Particles at the Oil/Water Interface --- p.114 / Chapter 4.2.5. --- Mesostructures at the Interface --- p.118 / Chapter 4.3. --- References and Notes --- p.122

Thesis (Ph. D.)--Lehigh University, 2004. / Includes bibliographical references and vita.

+ and the rate constant is quantified for the first time. The aforementioned spectroelectrochemical channel cell was then adopted to scrutinise the reactive dyeing kinetics on a cotton fabric. Kinetic results showed that the dye adsorption to the fabric is controlled by a solid-liquid interfacial reaction which is first order with respect to the surface concentration of the dye. However, the rate of this process is governed by the availability of the reaction sites for adsorption of dye molecules onto the fabric surface. It was demonstrated that the presence of supporting electrolyte in high pH media, and mercerisation pretreatment of the fabric, are essential to increase the dye uptake rate. Ex situ AFM studies suggested that mercerisation leads to a disordered fibre surface which may be responsible for the enhanced dye absorption rate.

No description available.

Thesis (PhD)--University of South Australia, 2003.

Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Document formatted into pages; contains xxi, 225 p.; also includes graphics (some col.). Includes bibliographical references (p. 218-225). Available online via OhioLINK's ETD Center

膠體顆粒吸附在油水介面的現象最近幾年引起極大的關注。一方面，受限在油水介面的膠體顆粒可以用作一個很好的模型體系來研究一些基本物理問題，例如二維結晶，擠壓以及其它相轉變問題。另一方面，在許多工業產品和處理過程中，例如食品，抗沫劑製備，以及原油乳液處理中膠體顆粒在油水介面的行為扮演著極為重要的角色。 / 微凝膠，一種軟膠體顆粒，也可以作為乳化劑用來穩定製備乳液。微凝膠在許多方面和普通膠體顆粒有著相同的行為。但是，微凝膠顆粒，作為一種三維交聯的高分子網狀鏈，在良性溶劑裡會膨脹。之前已經有報導明確指出這種微凝膠顆粒可以用來穩定的乳液。並且這些乳液的穩定性可控，此性質在小分子乳化劑和普通膠體顆粒體系是無法實現的。但是，這些微凝膠顆粒製備的乳液的穩定以及不穩定的作用機制至今尚有許多爭論。具體來說，這些微凝膠是如何吸附到油水面，什麼因素控制著這些吸附行為，微凝膠在油水介面如何行為，吸附在油水介面的微凝膠如何動態的回應外界條件的改變，統統不清楚。 / 本論文首先旨在深入瞭解微凝膠在油水介面的動態行為，然後用這些微凝膠穩定的乳液作為範本製備出多功能材料。本論文一共包括八部分，這八部分全部圍繞著微凝膠在油水介面的行為而展開。第一部分將介紹微凝膠應用在油水介面的研究已經取得的進展。第二部分將介紹彎曲的油水介面以及本論文主要用到的儀器。在第三部分，我們將會介紹微凝膠的製備與表徵。第四部分，我們集中於微凝膠是如何吸附到油水介面。我們發現微凝膠的柔軟，稀鬆，以及可變形決定了微凝膠的吸附過程。第五部分，我們探討為什麼油水介面動態張力在微凝膠的相轉變溫度附近有個最低值。通過對介面張力，溫度還有時間進行三維作圖，我們發現介面張力在微凝膠相轉變溫度附近(308.1K) 存在一個峰穀。這個峰谷的形成是由微凝膠的變形性以及它們之間相互作用所導致的。這些微凝膠吸附在油水介面之後形成一個新的微凝膠膜隔離開水與油，這層微凝膠險主導著油水介面的性質。第六部分，基於以上理解，我們在相轉變溫度附近創建了一個微凝膠未鋪滿的油水介面來研究微凝膠顆粒在一個受限的環境下的溫敏性行為。降低溫度，微凝膠在油水介面經歷一個極慢的舒張過程。但是升高溫度，微凝膠並沒有塌縮。第仁部分，我們首先應用微凝膠作為唯一穩定劑製備了一種高內相乳液，然後以此乳液為範本製備了多功能材料。最後一部分，縱觀全文，我們的結論是微凝膠的變形性以及它們之間的相互作用對於微凝膠在油水介面的行為起著非常重要的角色:包括微凝膠在油水介面的吸附行為，微凝膠在油水介面的溫敏性行為，油水介面的流變性能以及多功能材料的性能。 / The adsorption phenomena of colloidal particles at the liquid-liquids interfaces have received tremendous interests in recent years. On the fundamental side, interest stems from the fact that colloidal particles confined to the interfaces can serve as an elegant system for fundamental studies of physical processes, such as two-dimensional crystallization, jamming and other phase transitions. On the practical side, interest arises as a result of demonstrated importance of the behavior of colloidal particles at the interfaces for applications in many industrial products and processes such as the production of food, anti-foam formulations, and crude oil. / In recent years, soft particles, like microgels are also employed as emulsifiers for making emulsions. These microgel particles resemble colloidal particles in many aspects. However, structurally, microgel particles constitute a three-dimensional covalently crosslinked network and can swell up in good solvents. It has been reported that emulsions stabilized by these soft microgel particles can offer an unprecedented degree of control of emulsion stability, well beyond what can be achieved by using small molecular surfactants or conventional particles. However, the stabilization and destabilization mechanism involving such soft and deformable microgels is still a matter of debate. Specifically, how microgels adsorb onto the oil-water interfaces; what parameters control the microgel adsorption; how these microgels behave at the interfaces; and how these microgels respond to environmental triggers after adsorption, are unclear. / This thesis aims at first gaining a fundamental understanding of the microgels dynamic behaviors at the oil-water interfaces, and then using this system to fabricate functional materials. This thesis contains eight parts; all of them are connected with soft microgels at the oil-water interfaces. The first part of this thesis introduces the soft microgels’ performance at the oil-water interfaces. The second part focuses on the curved oil-water interfaces and the instrument we will use in this thesis. In the third part, we will present the preparations and characterizations of microgels. The fourth part addresses the microgels adsorption behaviors at the oil-water interfaces. Our results clearly show that deformability of microgel particles plays a vital role in their adsorption behaviors at the oil-water interfaces. In the fifth part, we discuss why interfacial tension (γ) exhibits a minimum in the vicinity of PNIPAM-related microgel volume phase transition temperature (VPTT). Our results suggest that, this observed minimum can be attributed to highest deformability of microgels around VPTT as well as the interactions among the adsorbed microgels. Moreover, our results reveal that unlike conventional solid particles, the adsorbed microgels are not wetted by both oil and water. On the contrary, they will form an intruding microgel layer separating the oil and water phases, which ultimately dominates the oil-water interfacial properties. Based on the above understanding, in the sixth part, we create microgels partially covered oil-water interfaces, and investigate the microgels thermal behaviors under a confined condition. Our results show that microgels undergo an extremely slow swelling process at the oil-water interfaces. In addition, microgels would not collapse upon heating. In the seventh part of this thesis, we present the preparation of high internal phase emulsions (HIPEs) by solely using soft microgels as emulsifiers. Furthermore, we demonstrate that these microgels-stabilized HIPEs can be good templates for the preparation of hierarchical porous functional materials. Based on our investigations, in the final part, we summary the importance of microgel deformability and their interactions on microgels behaviors at the oil-water interfaces: including their adsorption dynamics, thermal-responsive behaviors, oil-water interfacial rheology properties and functional materials properties. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Li, Zifu. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / 摘要 --- p.I / ABSTRACT --- p.III / ACKNOWLEDGEMENT --- p.V / TABLE OF CONTENTS --- p.VII / Chapter CHAPTER 1 --- INTRODUCTION AND BACKGROUND --- p.1 / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.1.1 --- Surfactant-stabilized emulsions --- p.1 / Chapter 1.1.2 --- Particle-stabilized emulsions --- p.3 / Chapter 1.2 --- Microgels as particulate emulsifiers in Pickering Emulsions --- p.6 / Chapter 1.2.1 --- Literature survey of microgels at interfaces --- p.7 / Chapter 1.2.2 --- Discussions and conclusions --- p.16 / Chapter 1.3 --- Theme of this thesis --- p.18 / Chapter 1.4 --- References and Notes --- p.19 / Chapter CHAPTER 2 --- THE FUNDAMENTALS OF CURVED OIL-WATER INTERFACE --- p.21 / Chapter 2.1 --- Introduction --- p.21 / Chapter 2.2 --- Pendant drop tensiometer --- p.22 / Chapter 2.3 --- The dynamic interfacial tension --- p.26 / Chapter 2.3.1 --- Two surfactant adsorption mechanisms --- p.27 / Chapter 2.4 --- Investigation of one single interface --- p.29 / Chapter 2.4.1 --- Pure heptane-water interface --- p.30 / Chapter 2.4.2 --- Heptane-BSA protein solution interface --- p.35 / Chapter 2.5 --- Dilatation rheology --- p.41 / Chapter 2.6 --- Conclusions --- p.42 / Chapter 2.7 --- References and Notes --- p.43 / Chapter CHAPTER 3 --- SYNTHESIS AND CHARACTERIZATION OF PNIPAM-RELATED MICROGELS --- p.45 / Chapter 3.1 --- Introduction --- p.45 / Chapter 3.2 --- Microgels preparation and characterization --- p.56 / Chapter 3.2.1 --- Preparation of microgel samples used in this thesis --- p.57 / Chapter 3.2.2 --- Microgels characterization --- p.59 / Chapter 3.3 --- Conclusions --- p.63 / Chapter 3.4 --- References and Notes --- p.63 / Chapter CHAPTER 4 --- MICROGEL ADSORPTION BEHAVIORS AT THE OIL-WATER INTERFACES: THE KINETIC STUDY --- p.65 / Chapter 4.1 --- Introduction --- p.65 / Chapter 4.2 --- Results and discussions --- p.67 / Chapter 4.2.1 --- The effect of microgel concentration: below VPTT --- p.68 / Chapter 4.2.2 --- Microgel concentration effect on dynamic interfacial tension: above VPTT of microgels --- p.73 / Chapter 4.2.3 --- Temperature effect on dynamic interfacial tension well above VPTT --- p.78 / Chapter 4.2.4 --- Diffusion controlled process --- p.81 / Chapter 4.2.5 --- Kinetic controlled process --- p.85 / Chapter 4.3 --- Conclusions --- p.93 / Chapter 4.4 --- References and Note --- p.95 / Chapter CHAPTER 5 --- ANOMALOUS INTERFACIAL TENSION VALLEYS DURING THE VOLUME PHASE TRANSITION OF PNIPAM MICROGELS AT THE OIL-WATER INTERFACE --- p.96 / Chapter 5.1 --- Introduction --- p.96 / Chapter 5.2 --- The interfacial tension valleys --- p.97 / Chapter 5.3 --- Discussions --- p.106 / Chapter 5.4 --- Conclusions --- p.115 / Chapter 5.5 --- References and Notes --- p.115 / Chapter CHAPTER 6 --- THE THERMAL BEHAVIOR OF MICROGELS CONFINED AT THE OIL-WATER INTERFACES: REVERSIBLE OR IRREVERSIBLE? --- p.117 / Chapter 6.1 --- Introduction --- p.117 / Chapter 6.2 --- Microgels thermal behaviors confined at interfaces --- p.118 / Chapter 6.3 --- Conclusions --- p.137 / Chapter 6.4 --- References and Notes --- p.138 / Chapter CHAPTER 7 --- FUNCTIONAL MATERIALS FROM MICROGELS AT INTERFACES --- p.139 / Chapter 7.1 --- High internal phase emulsions (HIPEs) --- p.139 / Chapter 7.2 --- Microgels stabilized HIPEs --- p.140 / Chapter 7.2.1 --- Preparations --- p.140 / Chapter 7.2.2 --- Characterizations --- p.141 / Chapter 7.3 --- Materials from microgels stabilized emulsions --- p.144 / Chapter 7.3.1 --- Porous membranes --- p.144 / Chapter 7.3.2 --- Hierarchical porous materials --- p.145 / Chapter 7.4 --- Conclusions --- p.146 / Chapter 7.5 --- References and Notes --- p.147 / Chapter CHAPTER 8 --- OVERVIEW OF MICROGELS AT INTERFACES --- p.148 / Chapter 8.1 --- Summary of microgels at interfaces --- p.148 / Chapter 8.2 --- Outlook and further experiments --- p.150 / CURRICULUM VITAE --- p.152

No description available.

We observed the evolution of unstable fluid interfaces in experiments on viscous fingering, pinch-off, and bouncing jets. If we can first identify classes of universal behavior, then we can begin building a unified framework to understand nonlinear processes. We performed the first experimental test of the harmonic moments of viscous fingering patterns, grown by injecting air into a thin layer of silicone oil, which was confined between two closely spaced plates, called a Hele-Shaw cell. We observed that the predicted decay of the moments was accurate within our measurement uncertainty, which confirmed the predicted conservation of the moments for zero surface tension. With greater forcing, the air bubble will undergo a secondary tip-splitting instability, where the fingers of air fork into two or more fingers. We discovered two selection rules for the changing base width and the nearly invariant opening angle of fjords, which are the regions of oil between the fingers of air. We then compared our experiments on viscous fingering with diffusion-limited aggregation (DLA), a model of un-stable growth. We calculated that DLA and viscous fingering have the same spectrum of singularities [called f([alpha])] within measurement uncertainty. Since the spectrum is a global encapsulation of the growth dynamics and scaling properties, we say that the two processes are in the same scaling universality class. All of these results for viscous fingering are expected to apply to other physical systems which approximate Laplacian growth, a model of an interface where its growth rate is determined by the local gradient of a field [phi] obeying Laplace's equation [gradient² phi] = 0. Next we present preliminary work on the experimental test of two predictions for flows in Hele-Shaw cells: 1) soliton-like behavior of two viscous domains and 2) self-similar, universal pinch-off of an inviscid bubble in a viscous liquid. Finally, we report our observations and analysis of a liquid stream with constant viscosity (i.e. Newtonian) which rebounds from the free surface of a moving bath. The stream bounces on a thin layer of lubricating air which is replenished by the relative motion of the jet and the bath.