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DLVO theory

The DLVO theory explains the aggregation of aqueous dispersions quantitatively and describes the force between charged surfaces interacting through a liquid medium. It combines the effects of the van der Waals attraction and the electrostatic rep ...

Donnan potential

Donnan potential appears as a result of Donnan equilibrium, named after Frederick G. Donnan, which refers to the distribution of ion species between two ionic solutions separated by a semipermeable membrane or boundary. The boundary layer maintai ...

Double layer (biology)

In biological systems, a double layer is the surface where two different phases of matter are in contact. Biological double layers are much like their interfacial counterparts, but with several notable distinctions. The surface of biological cell ...

Double layer forces

Double layer forces occur between charged objects across liquids, typically water. This force acts over distances that are comparable to the Debye length, which is on the order of one to a few tenths of nanometers. The strength of these forces in ...

Dynamic light scattering

Dynamic light scattering is a technique in physics that can be used to determine the size distribution profile of small particles in suspension or polymers in solution. In the scope of DLS, temporal fluctuations are usually analyzed by means of t ...

Electric sonic amplitude

Electric sonic amplitude is an electroacoustic phenomenon that is the reverse to colloid vibration current. It occurs in colloids, emulsions and other heterogeneous fluids under the influence of an oscillating electric field. This field moves par ...

Electrodiffusiophoresis

Electrodiffusiophoresis is a motion of particles dispersed in liquid induced by external homogeneous electric field, which makes it similar to electrophoresis.

Electrophoresis (disambiguation)

Electrophoresis is the motion of dispersed particles relative to a fluid under the influence of a spatially uniform electric field. "Electrophoresis" can also refer to:

Electrophoretic light scattering

Electrophoretic light scattering is based on dynamic light scattering. The frequency shift or phase shift of an incident laser beam depends on the dispersed particles mobility. In the case of dynamic light scattering, Brownian motion causes parti ...

Emulsion dispersion

Emulsions are thermodynamically unstable liquid/liquid dispersions that are stabilized. Emulsion dispersion is not about reactor blends for which one polymer is polymerized from its monomer in the presence of the other polymers; emulsion dispersi ...

Gibbs–Donnan effect

The Gibbs–Donnan effect is a name for the behaviour of charged particles near a semi-permeable membrane that sometimes fail to distribute evenly across the two sides of the membrane. The usual cause is the presence of a different charged substanc ...

Gold number

Gold Number is a term used in colloidal chemistry. It is defined as the minimum amount of protective colloid in milligrams which change the colour from red to violet of 10ml gold solution by the addition of 1ml 10% NaCl solution. Coagulation of g ...

Imbibition

Imbibition is a special type of diffusion that takes place when water is adsorbed by solids-colloids causing an increase in volume. Examples include the absorption of water by seeds and dry wood. If it were not for the pressure due to imbibition, ...

Krafft temperature

Krafft temperature is defined as the temperature at which the solubility of a surfactant is equal to the surfactants critical micelle concentration at the same temperature. It is named after German chemist Friedrich Krafft. Below the Krafft tempe ...

Micellar solubilization

Micellar solubilization is the process of incorporating the solubilizate into or onto micelles. Solublization may occur in a system consisting of a solvent, an association colloid, and at least one other solubilizate.

Micellar solutions

A micellar solution consists of a dispersion of micelles in a solvent. Micelles consist of aggregated amphiphiles, and in a micellar solution these are in equilibrium with free, unaggregated amphiphiles. Micellar solutions form when the concentra ...

Micelle

A micelle or micella is an aggregate of surfactant molecules dispersed in a liquid colloid. A typical micelle in aqueous solution forms an aggregate with the hydrophilic "head" regions in contact with surrounding solvent, sequestering the hydroph ...

Microelectrophoresis

Microelectrophoresis is a method of studying electrophoresis of various dispersed particles using optical microscopy. This method provides image of moving particles, which is its unique advantage. e.g. observation of RBCs, neutrophiles and bacter ...

Miniemulsion

A miniemulsion is a special case of emulsion. A miniemulsion is obtained by shearing a mixture comprising two immiscible liquid phases, one or more surfactants and, possibly, one or more co-surfactants. There are two general types of methods for ...

Multiangle light scattering

Multiangle light scattering describes a technique for measuring the light scattered by a sample into a plurality of angles. It is used for determining both the absolute molar mass and the average size of molecules in solution, by detecting how th ...

Mycosubtilin

Mycosubtilin is a natural lipopeptide with antifungal and hemolytic activities and isolated from Bacillus species. It belongs to the iturin lipopeptide family.

Nephelometer

A nephelometer is an instrument for measuring the concentration of suspended particulates in a liquid or gas colloid. A nephelometer measures suspended particulates by employing a light beam and a light detector set to one side of the source beam ...

Ostwald ripening

Ostwald ripening is a phenomenon observed in solid solutions or liquid sols that describes the change of an inhomogeneous structure over time, i.e., small crystals or sol particles dissolve, and redeposit onto larger crystals or sol particles. Di ...

Particle aggregation

Particle agglomeration refers to formation of assemblages in a suspension and represents a mechanism leading to the functional destabilization of colloidal systems. During this process, particles dispersed in the liquid phase stick to each other, ...

Particle deposition

Particle deposition is the spontaneous attachment of particles to surfaces. The particles in question are normally colloidal particles, while the surfaces involved may be planar, curved, or may represent particles much larger in size than the dep ...

Random sequential adsorption

Random sequential adsorption refers to a process where particles are randomly introduced in a system, and if they do not overlap any previously adsorbed particle, they adsorb and remain fixed for the rest of the process. RSA can be carried out in ...

Particle size

Particle size is a notion introduced for comparing dimensions of solid particles, liquid particles, or gaseous particles. The notion of particle size applies to colloidal particles, particles in ecology, particles present in granular material, an ...

Point of zero charge

The point of zero charge is generally described as the pH at which the net charge of total particle surface is equal to zero, which concept has been introduced in the studies dealt with colloidal flocculation to explain pH affecting the phenomeno ...

Poisson–Boltzmann equation

The Poisson–Boltzmann equation is a useful equation in many settings, whether it be to understand physiological interfaces, polymer science, electron interactions in a semiconductor, or more. It aims to describe the distribution of the electric p ...

Potential determining ion

When placed into solution, salts begin to dissolve and form ions. This is not always in equal proportion, due to the preference of an ion to be dissolved in a given solution. The ability of an ion to preferentially dissolve over its counterion is ...

Relative permittivity

The relative permittivity of a material is its permittivity expressed as a ratio relative to the vacuum permittivity. Permittivity is a material property that affects the Coulomb force between two point charges in the material. Relative permittiv ...

Settling

Settling is the process by which particulates settle to the bottom of a liquid and form a sediment. Particles that experience a force, either due to gravity or due to centrifugal motion will tend to move in a uniform manner in the direction exert ...

Sodicity

The Sodium adsorption ratio is an irrigation water quality parameter used in the management of sodium-affected soils. It is an indicator of the suitability of water for use in agricultural irrigation, as determined from the concentrations of the ...

Sol (colloid)

A sol is a colloid made out of very small solid particles in a continuous liquid medium. Sols are quite stable and show the Tyndall effect. Examples include blood, pigmented ink, cell fluids, paint, antacids and mud. Artificial sols may be prepar ...

Stokes's law of sound attenuation

Stokess law of sound attenuation is a formula for the attenuation of sound in a Newtonian fluid, such as water or air, due to the fluids viscosity. It states that the amplitude of a plane wave decreases exponentially with distance traveled, at a ...

Streaming potential/current

A streaming current and streaming potential are two interrelated electrokinetic phenomena studied in the areas of surface chemistry and electrochemistry. They are an electric current or potential which originates when an electrolyte is driven by ...

Supermicelle

Supermicelle is a hierarchical micelle structure where individual components are also micelles. Supermicelles are formed via bottom-up chemical approaches, such as self-assembly of long cylindrical micelles into radial cross-, star- or dandelion- ...

Surfactin

Surfactin is a very powerful surfactant commonly used as an antibiotic. It is a bacterial cyclic lipopeptide, largely prominent for its exceptional surfactant power. Its amphiphilic properties help this substance to survive in both hydrophilic an ...

Thermodynamics of micellization

The surfactant’s critical micelle concentration plays a factor in Gibbs free energy of micellization. The exact concentration of the surfactants that yield the aggregates being thermodynamically soluble is the CMC. The Krafft temperature determin ...

Third phase

Third phase is the term for a stable emulsion which forms in a liquid–liquid extraction when the original two phases are mixed. The third phase can be caused by a detergent surfactant or a fine solid. While third phase is a term for an unwanted e ...

Ultrasound attenuation spectroscopy

Ultrasound attenuation spectroscopy is a method for characterizing properties of fluids and dispersed particles. It is also known as acoustic spectroscopy There is an international standard for this method. Measurement of attenuation coefficient ...

Unilamellar liposome

An unilamellar liposome is a spherical chamber/vesicle, bounded by a single bilayer of an amphiphilic lipid or a mixture of such lipids, containing aqueous solution inside the chamber. Unilamellar liposomes are used to study biological systems an ...

Volume viscosity

Volume viscosity is a material property relevant for characterizing fluid flow. Common symbols are ζ, μ ′, μ b, κ {\displaystyle \zeta,\mu,\mu _{\mathrm {b} },\kappa } or ξ {\displaystyle \xi }. It has dimensions), and the corresponding SI unit i ...

Zeta potential

Zeta potential is a scientific term for electrokinetic potential in colloidal dispersions. In the colloidal chemistry literature, it is usually denoted using the Greek letter zeta, hence ζ-potential. The usual units are volts or millivolts. From ...

Zubbles

Zubbles is a commercial name for colored soap bubbles. Zubbles claim to fame is that they are the first colored soap bubbles that do not leave stains. Instead they fade away with exposure to air, pressure, and water. Popular Science named Zubbles ...

Chamaelirium

Chamaelirium is a genus of flowering plants containing the single species Chamaelirium luteum, commonly known as blazing-star, devils bit, false unicorn, fairy wand, and helonias. It is a perennial herb native to the eastern United States. It can ...

Flemingia macrophylla

Flemingia macrophylla a is woody leguminous shrub belonging to the genus Flemingia. It is a multipurpose plant widely used in agriculture, crop improvement, fodder, dyes and for various therapeutic purposes. Perhaps, it is the most versatile spec ...

Flemingia vestita

Flemingia vestita ex Baker Kuntze; Moghania procumbens Mukerjee) famously known as Sohphlang is a nitrogen fixing herb with characteristic tuberous root, belonging to the genus Flemingia. The root is edible and is a common vegetable in some Asian ...

Glycerite

A traditional glycerite is a fluid extract of an herb or other medicinal substance made using glycerin as the majority of the fluid extraction medium.

Latin American and Caribbean Bulletin of Medicinal and Aromatic Plants

The Boletin latinoamericano y del caribe de plantas medicinales y aromaticas is a bimonthly peer-reviewed scientific journal covering research on all aspects of medicinal and aromatic plants. Articles are published in Spanish or English.