Multimodal Dispersion of Nanoparticles: a Comprehensive Evaluation of Size Distribution with 9 Size Measurement Methods
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Mechanical Dispersion of Clay from Soil Into Water: Readily-Dispersed and Spontaneously-Dispersed Clay Ewa A
Int. Agrophys., 2015, 29, 31-37 doi: 10.1515/intag-2015-0007 Mechanical dispersion of clay from soil into water: readily-dispersed and spontaneously-dispersed clay Ewa A. Czyż1,2* and Anthony R. Dexter2 1Department of Soil Science, Environmental Chemistry and Hydrology, University of Rzeszów, Zelwerowicza 8b, 35-601 Rzeszów, Poland 2Institute of Soil Science and Plant Cultivation (IUNG-PIB), Czartoryskich 8, 24-100 Puławy, Poland Received July 1, 2014; accepted October 10, 2014 A b s t r a c t. A method for the experimental determination of Clay particles can either flocculate or disperse in aque- the amount of clay dispersed from soil into water is described. The ous solution. When flocculation occurs, the particles com- method was evaluated using soil samples from agricultural fields bine to form larger, compound particles such as soil in 18 locations in Poland. Soil particle size distributions, contents microaggregates. When dispersion occurs, the particles of organic matter and exchangeable cations were measured by separate in suspension due to their electrical charge. Clay standard methods. Sub-samples were placed in distilled water flocculation leads to soils that are considered to be stable in wa- and were subjected to four different energy inputs obtained by ter whereas dispersion is associated with soils that are consi- different numbers of inversions (end-over-end movements). The dered to be unstable in water. We may note that this termi- amounts of clay that dispersed into suspension were measured by light scattering (turbidimetry). An empirical equation was devel- nology is the opposite of that used in colloid science where oped that provided an approximate fit to the experimental data for the terms ‘stable’ and ‘unstable’ are used in relation to the turbidity as a function of number of inversions. -
Dispersity in Polymer Science
Pure Appl. Chem., Vol. 81, No. 2, pp. 351–353, 2009. doi:10.1351/PAC-REC-08-05-02 © 2009 IUPAC INTERNATIONAL UNION OF PURE AND APPLIED CHEMISTRY POLYMER DIVISION SUBCOMMITTEE ON POLYMER TERMINOLOGY* DISPERSITY IN POLYMER SCIENCE (IUPAC Recommendations 2009) Prepared by a Working Group consisting of R. G. GILBERT (AUSTRALIA), M. HESS (GERMANY), A. D. JENKINS (UK), R. G. JONES (UK), P. KRATOCHVÍL (CZECH REPUBLIC), AND R. F. T. STEPTO (UK) Prepared for publication by R. F. T. STEPTO‡ Polymer Science and Technology Group, Manchester Materials Science Centre, School of Materials, The University of Manchester, Grosvenor Street, Manchester, M1 7HS, UK *Membership of the Subcommittee on Polymer Terminology† during the preparation of this report (2003–2008) was as follows: M. Barón (Argentina, Secretary until 2003); M. Hess (Germany, Chairman to 2005, Secretary, 2006–2007); R. G. Jones (UK, Secretary 2003–2005, Chairman, from 2006); T. Kitayama (Japan, Secretary, from 2008); G. Allegra (Italy); T. Chang (Korea); C. dos Santos (Brazil); A. Fradet (France); K. Hatada (Japan); J. He (China); K.-H. Hellwich (Germany); R. C. Hiorns (France); P. Hodge (UK); K. Horie (Japan); A. D. Jenkins (UK); J.-I. Jin (Korea); J. Kahovec (Czech Republic); P. Kratochvíl (Czech Republic); P. Kubisa (Poland); I. Meisel (Germany); W. V. Metanomski (USA); V. Meille (Italy); I. Mita (Japan); G. Moad (Australia); W. Mormann (Germany); C. Ober (USA); S. Penczek (Poland); L. P. Rebelo (Portugal); M. Rinaudo (France); I. Schopov (Bulgaria); M. Schubert (USA); F. Schué (France); V. P. Shibaev (Russia); S. Słomkowski (Poland); R. F. T. Stepto (UK); D. Tabak (Brazil); J.-P. -
Colloidal Suspensions
Chapter 9 Colloidal suspensions 9.1 Introduction So far we have discussed the motion of one single Brownian particle in a surrounding fluid and eventually in an extaernal potential. There are many practical applications of colloidal suspensions where several interacting Brownian particles are dissolved in a fluid. Colloid science has a long history startying with the observations by Robert Brown in 1828. The colloidal state was identified by Thomas Graham in 1861. In the first decade of last century studies of colloids played a central role in the development of statistical physics. The experiments of Perrin 1910, combined with Einstein's theory of Brownian motion from 1905, not only provided a determination of Avogadro's number but also laid to rest remaining doubts about the molecular composition of matter. An important event in the development of a quantitative description of colloidal systems was the derivation of effective pair potentials of charged colloidal particles. Much subsequent work, largely in the domain of chemistry, dealt with the stability of charged colloids and their aggregation under the influence of van der Waals attractions when the Coulombic repulsion is screened strongly by the addition of electrolyte. Synthetic colloidal spheres were first made in the 1940's. In the last twenty years the availability of several such reasonably well characterised "model" colloidal systems has attracted physicists to the field once more. The study, both theoretical and experimental, of the structure and dynamics of colloidal suspensions is now a vigorous and growing subject which spans chemistry, chemical engineering and physics. A colloidal dispersion is a heterogeneous system in which particles of solid or droplets of liquid are dispersed in a liquid medium. -
Known As the Dispersed Phase), Distributed Throughout a Continuous Phase (Known As Dispersion Medium)
COLLOIDAL DISPERSIONS Dispersed systems consist of particulate matter (known as the dispersed phase), distributed throughout a continuous phase (known as dispersion medium). CLASSIFICATION OF DISPERSED SYSTEMS On the basis of mean particle diameter of the dispersed material, three types of dispersed systems are generally considered: a) Molecular dispersions b) Colloidal dispersions, and c) Coarse dispersions Molecular dispersions are the true solutions of a solute phase in a solvent. The solute is in the form of separate molecules homogeneously distributed throughout the solvent. Example: aqueous solution of salts, glucose Colloidal dispersions are micro-heterogeneous dispersed systems. The dispersed phases cannot be separated under gravity or centrifugal or other forces. The particles do not mix or settle down. Example: aqueous dispersion of natural polymer, colloidal silver sols, jelly Coarse dispersions are heterogeneous dispersed systems in which the dispersed phase particles are larger than 0.5µm. The concentration of dispersed phase may exceed 20%. Example: pharmaceutical emulsions and suspensions COMPARISON OF CHARACTERISTICS THREE DISPERSED SYSTEMS Molecular dispersions Colloidal dispersions Coarse dispersions 1. Particle size <1 nm 1 nm to 0.5 µm >0.5 µm 2. Appearance Clear, transparent Opalescent Frequently opaque 3. Visibility Invisible in electron Visible in electron Visible under optical microscope microscope microscope or naked eye 4. Separation Pass through semipermeable Pass through filter paper but Do not pass through -
CHAPTER 3 Transport and Dispersion of Air Pollution
CHAPTER 3 Transport and Dispersion of Air Pollution Lesson Goal Demonstrate an understanding of the meteorological factors that influence wind and turbulence, the relationship of air current stability, and the effect of each of these factors on air pollution transport and dispersion; understand the role of topography and its influence on air pollution, by successfully completing the review questions at the end of the chapter. Lesson Objectives 1. Describe the various methods of air pollution transport and dispersion. 2. Explain how dispersion modeling is used in Air Quality Management (AQM). 3. Identify the four major meteorological factors that affect pollution dispersion. 4. Identify three types of atmospheric stability. 5. Distinguish between two types of turbulence and indicate the cause of each. 6. Identify the four types of topographical features that commonly affect pollutant dispersion. Recommended Reading: Godish, Thad, “The Atmosphere,” “Atmospheric Pollutants,” “Dispersion,” and “Atmospheric Effects,” Air Quality, 3rd Edition, New York: Lewis, 1997, pp. 1-22, 23-70, 71-92, and 93-136. Transport and Dispersion of Air Pollution References Bowne, N.E., “Atmospheric Dispersion,” S. Calvert and H. Englund (Eds.), Handbook of Air Pollution Technology, New York: John Wiley & Sons, Inc., 1984, pp. 859-893. Briggs, G.A. Plume Rise, Washington, D.C.: AEC Critical Review Series, 1969. Byers, H.R., General Meteorology, New York: McGraw-Hill Publishers, 1956. Dobbins, R.A., Atmospheric Motion and Air Pollution, New York: John Wiley & Sons, 1979. Donn, W.L., Meteorology, New York: McGraw-Hill Publishers, 1975. Godish, Thad, Air Quality, New York: Academic Press, 1997, p. 72. Hewson, E. Wendell, “Meteorological Measurements,” A.C. -
GPC - Gel Permeation Chromatography Aka Size Exclusion Chromatography- SEC
GPC - Gel Permeation Chromatography aka Size Exclusion Chromatography- SEC Wendy Gavin Biomolecular Characterization Laboratory Version 1 May 2016 1 Table of Contents 1. GPC Introduction………………………………………………………. Page 3 2. How GPC works………………………………………………………... Page 5 3. GPC Systems…………………………………………………………… Page 7 4. GPC/SEC Separations – Theory and System Considerations… Page 9 5. GPC Reports……………………………………………………………. Page 10 6. Calibrations of GPC systems………………………………………... Page 14 7. GPC preparation……………………………………………………….. Page 16 8. Alliance System………………………………………………………… Page 17 9. GPC columns…………………………………………………………… Page 18 2 1. GPC Introduction Gel permeation chromatography (GPC) is one of the most powerful and versatile analytical techniques available for understanding and predicting polymer performance. It is the most convenient technique for characterizing the complete molecular weight distribution of a polymer. Why is GPC important? GPC can determine several important parameters. These include number average molecular weight (Mn), weight average molecular weight(Mw) Z weight average molecular weight(Mz), and the most fundamental characteristic of a polymer its molecular weight distribution(PDI) These values are important, since they affect many of the characteristic physical properties of a polymer. Subtle batch-to-batch differences in these measurable values can cause significant differences in the end-use properties of a polymer. Some of these properties include: Tensile strength Adhesive strength Hardness Elastomer relaxation Adhesive tack Stress-crack resistance Brittleness Elastic modules Cure time Flex life Melt viscosity Impact strength Tear Strength Toughness Softening temperature 3 Telling good from bad Two samples of the same polymer resin can have identical tensile strengths and melt viscosities, and yet differ markedly in their ability to be fabricated into usable, durable products. -
Lecture Notes on Structure and Properties of Engineering Polymers
Structure and Properties of Engineering Polymers Lecture: Microstructures in Polymers Nikolai V. Priezjev Textbook: Plastics: Materials and Processing (Third Edition), by A. Brent Young (Pearson, NJ, 2006). Microstructures in Polymers • Gas, liquid, and solid phases, crystalline vs. amorphous structure, viscosity • Thermal expansion and heat distortion temperature • Glass transition temperature, melting temperature, crystallization • Polymer degradation, aging phenomena • Molecular weight distribution, polydispersity index, degree of polymerization • Effects of molecular weight, dispersity, branching on mechanical properties • Melt index, shape (steric) effects Reading: Chapter 3 of Plastics: Materials and Processing by A. Brent Strong https://www.slideshare.net/NikolaiPriezjev Gas, Liquid and Solid Phases At room temperature Increasing density Solid or liquid? Pitch Drop Experiment Pitch (derivative of tar) at room T feels like solid and can be shattered by a hammer. But, the longest experiment shows that it flows! In 1927, Professor Parnell at UQ heated a sample of pitch and poured it into a glass funnel with a sealed stem. Three years were allowed for the pitch to settle, and in 1930 the sealed stem was cut. From that date on the pitch has slowly dripped out of the funnel, with seven drops falling between 1930 and 1988, at an average of one drop every eight years. However, the eight drop in 2000 and the ninth drop in 2014 both took about 13 years to fall. It turns out to be about 100 billion times more viscous than water! Pitch, before and after being hit with a hammer. http://smp.uq.edu.au/content/pitch-drop-experiment Liquid phases: polymer melt vs. -
Food Dispersion Systems Process Stabilization. a Review
───Food Technology ─── Food dispersion systems process stabilization. A review. Andrii Goralchuk, Olga Grinchenko, Olga Riabets, Оleg Kotlyar Kharkiv State University of Food Technology and Trade, Kharkiv, Ukraine Abstract Keywords: Introduction. The overview is given to systematize Emulsion information on the indicators, affecting the production and Foam stabilization of foams and emulsions, for applying the Stabilization existing regularities for more complex dispersed Rheology (polyphase) systems. Layers Materials and methods. Analytical studies of the production and stabilization of foams and polyphase dispersed systems published over the past 20 years. The research focuses on the foams, emulsions, foam emulsion systems and the systems, being simultaneously foam, Article history: emulsion and suspension. Results and discussion. Though foams and Received 28.11.2018 emulsions have similarities and their production differs in Received in revised form 15.08.2019 the dispersion rate, determined by the rate of surfactants Accepted 28.11.2019 adsorption. Emulsifying is faster than foaming, therefore, the production of foam emulsions can be sequential only. Coalescence, as a destruction indicator, is typical of foams and emulsions alike, and it is determined by the properties Corresponding author: of surfactants. Other indicators are determined by the features of the dispersion medium. The study systematized Andrii Goralchuk the factors, ensuring the stability of dispersion systems. The E-mail: structural mechanical factor is effective in -
Dilute Species Transport in Non-Newtonian, Single-Fluid, Porous Medium Systems
DILUTE SPECIES TRANSPORT IN NON-NEWTONIAN, SINGLE-FLUID, POROUS MEDIUM SYSTEMS Minge Jiang A technical report submitted to the faculty at the University of North Carolina at Chapel Hill in partial fulfillment of the requirements for the degree of Master of Science in Environmental Engineering in the Department of Environmental Sciences and Engineering in the Gillings School of Global Public Health. Chapel Hill 2019 Approved by: Cass T. Miller Orlando Coronell Jason D. Surratt i © 2019 Minge Jiang ALL RIGHTS RESERVED ii ABSTRACT Minge Jiang (Under the direction of Cass T. Miller) Vast reserves of natural gas held in tight shale formations have become accessible over the last two decades as a result of horizontal drilling and hydraulic fracturing. Hydraulic fracturing creates patterns of fractures that increase the permeability of the shale. The production of natural gas from such formations has led to the U.S. becoming a net exporter of natural gas, lowered energy costs, and led to a reduction in coal-fired power generation, thereby reducing greenhouse gas emissions. The hydraulic fracturing process is complex and poses environmental risks, which are not clearly understood. Many fundamental questions remain to be answered before these risks can be clearly understood and analyzed. The difficulties result from the injection and attempted recovery of non-Newtonian fluids, which often include many species considered pollutants if encountered in drinking water, under gravitationally and viscously unstable conditions. This work investigates how species disperse in non-Newtonian fluids, which is a topic that has received scant attention in the literature. Dispersion is a deviation from the mean rate of movement, and it is caused by a combination of factors including molecular diffusion, and pore-scale velocity distributions, which are in turn affected by viscosity variations. -
Ch 1 Questions-01162013
Colloidal Suspension Rheology Chapter 1 Study Questions 1. What forces act on a single colloidal particle suspended in a flowing fluid? Discuss the dependence of these forces on particle radius . 2. What are the interaction forces between particles in a solvent? What parameters affect their strength? 3. Discuss the range of the interparticle surface forces? 4. Explain what is meant by kinetic stability with regard to colloidal dispersions. 5. You are trying to flocculate a colloidal dispersion in a plant-size operation at 500 K using calcium oxide (CaO). In your laboratory, all you have available at the moment is sodium chloride (NaCl). At room temperature, you find that 2 mol/L NaCl is necessary to flocculate the colloidal dispersion. Estimate the concentration of CaO necessary to flocculate the dispersion in your plant operation. 6. What is the difference between the behavior of power law fluids and Bingham bodies at low stress levels? 7. What is the signature of the relaxation time for Maxwellian fluids in stress relaxation and in oscillatory experiments? 8. With regard to oscillatory shear experiments, explain the relative evolution of stress and strain curves as a function of time for (a) perfectly elastic materials, (b) perfectly inelastic (viscous) materials and (c) viscoelastic materials. 9. What is the role of a polymer in colloidal dispersion stability for a) Grafted or adsorbed polymer b) Dissolved, non-adsorbed polymer? 10. Discuss the characteristics of hard sphere suspension and difficulties in realizing this experimentally. 11. Define the dimensionless groups: De (Deborah number); Wi (Weissenberg number); Pe (Péclet number) 12. Why are colloidal particles defined by size limitations from nanometers to micrometers? 13. -
Impact of Particle Size and Polydispersity Index on the Clinical Applications of Lipidic Nanocarrier Systems
pharmaceutics Review Impact of Particle Size and Polydispersity Index on the Clinical Applications of Lipidic Nanocarrier Systems M. Danaei, M. Dehghankhold, S. Ataei, F. Hasanzadeh Davarani, R. Javanmard, A. Dokhani, S. Khorasani and M. R. Mozafari * ID Australasian Nanoscience and Nanotechnology Initiative, 8054 Monash University LPO, Clayton, Victoria 3168, Australia; [email protected] (M.Da.); [email protected] (M.De.); [email protected] (S.A.); [email protected] (F.H.D.); [email protected] (R.J.); [email protected] (A.D.); [email protected] (S.K.) * Correspondence: [email protected]; Tel.: +61-42433-9961 Received: 14 April 2018; Accepted: 17 May 2018; Published: 18 May 2018 Abstract: Lipid-based drug delivery systems, or lipidic carriers, are being extensively employed to enhance the bioavailability of poorly-soluble drugs. They have the ability to incorporate both lipophilic and hydrophilic molecules and protecting them against degradation in vitro and in vivo. There is a number of physical attributes of lipid-based nanocarriers that determine their safety, stability, efficacy, as well as their in vitro and in vivo behaviour. These include average particle size/diameter and the polydispersity index (PDI), which is an indication of their quality with respect to the size distribution. The suitability of nanocarrier formulations for a particular route of drug administration depends on their average diameter, PDI and size stability, among other parameters. Controlling and validating these parameters are of key importance for the effective clinical applications of nanocarrier formulations. This review highlights the significance of size and PDI in the successful design, formulation and development of nanosystems for pharmaceutical, nutraceutical and other applications. -
Dispersion Kernels for Water Wave Simulation
Dispersion Kernels for Water Wave Simulation Jose´ A. Canabal1 David Miraut1 Nils Thuerey2 Theodore Kim3;4 Javier Portilla5 Miguel A. Otaduy1 1URJC Madrid 2Technical University of Munich 3Pixar Animation Studios 4Universiy of California, Santa Barbara 5Instituto de Optica, CSIC Figure 1: Rain on the pond. Our wave simulation method captures the gravity waves present in the wakes produced by the paper birds, as well as the capillary waves produced by rain drops, all with correct scale-dependent velocities. The waves reflect on all the objects in the scene, both static and dynamic. The domain is 4 meters wide, and is simulated on a 1024 × 1024 grid, at just 1:6 sec. per frame. Abstract thesizing height field waves with correct dispersion [Tessendorf 2004b]. However, handling obstacle boundaries in the frequency We propose a method to simulate the rich, scale-dependent dynam- domain is computationally expensive, and quickly renders any ap- ics of water waves. Our method preserves the dispersion proper- proach in this direction impractical. Thus, users have to resort to lo- ties of real waves, yet it supports interactions with obstacles and is calized three-dimensional simulations [Nielsen and Bridson 2011], computationally efficient. Fundamentally, it computes wave accel- precomputations [Jeschke and Wojtan 2015], or height field ap- erations by way of applying a dispersion kernel as a spatially variant proaches with spatial filtering techniques [Kass and Miller 1990; filter, which we are able to compute efficiently using two core tech- Tessendorf 2008]. While the latter methods are typically fast, they nical contributions. First, we design novel, accurate, and compact only roughly approximate or even neglect dispersion effects.