Instability
Emulsion stability refers to the ability of an emulsion to resist change in its properties over time. There are three types of instability in emulsions: flocculation, creaming, and coalescence. Flocculation describes the process by which the dispersed phase comes out of suspension in the form of flakes. Coalescence is another form of instability - small droplets bump into each other within the media volume and continuously combine to form progressively larger droplets. Emulsions can also undergo creaming, where one of the substances migrates to the top (or the bottom, depending on the relative densities of the two phases) of the emulsion under the influence of buoyancy, or under the influence of the centripetal force induced when a centrifuge is used.
"Surface active substances" (or "surfactants") can increase the kinetic stability of emulsions so that the emulsion does not change significantly with time. A "non-ionic" surfactant solution can become self-contained under the force of its own surface tension, remaining in the shape of its previous container for some time after the container is removed.
Read more about this topic: Emulsion, Appearance and Properties
Other articles related to "instability":
... Instability Field Person(s) Named After Bénard instability Natural convection, Rayleigh–Bénard convection Henri Bénard Benjamin–Feir instability Surface gravity waves T ... Feir Buneman instability Plasma physics Oscar Buneman Cherenkov instability Plasma physics Pavel Alekseevič Čerenkov Chromo-Weibel instability Plasma physics E ... Weibel Crow instability Aerodynamics S ...
... After the instability has run its course, the system is typically "hotter" (the motions are more random) or rounder than before ... Instabilities in stellar systems include Bar instability of rapidly-rotating disks Jeans instability Firehose instability Gravothermal instability Radial-orbit instability Various instabilities in ...
... of gravity in higher dimensions are found to exhibit an instability to small perturbations ... It is very interesting to know the end point of this instability, particularly whether it leads to a phase transition forming a black hole ... higher dimensions and a critical dimension has been found to exist below which the end state of instability is a black hole phase, i.e ...
... The Omani invasion began a period of political instability and a quick succession of outside rulers took power with consequent destruction ... The years of almost constant warfare and instability in the period led to a demographic collapse – German geographer Carsten Niebuhr found in 1763 that Bahrain's 360 towns and ...
... In order for a boundary layer to be absolutely unstable (have an inviscid instability), it must satisfy Rayleigh's criterion namely Where represents the y-derivative and is the free stream velocity ... then, that viscosity must be an important factor in the instability ... however, is the Reynolds stress term and is the primary production method for instability growth ...
Famous quotes containing the word instability:
“Not only does the wind of accidents stir me according to its blowing, but I am also stirred and troubled by the instability of my attitude.”
—Michel de Montaigne (1533–1592)
“The difference between tragedy and comedy is the difference between experience and intuition. In the experience we strive against every condition of our animal life: against death, against the frustration of ambition, against the instability of human love. In the intuition we trust the arduous eccentricities we’re born to, and see the oddness of a creature who has never got acclimatized to being created.”
—Christopher Fry (b. 1907)
“What exacerbates the strain in the working class is the absence of money to pay for services they need, economic insecurity, poor daycare, and lack of dignity and boredom in each partner’s job. What exacerbates it in upper-middle class is the instability of paid help and the enormous demands of the career system in which both partners become willing believers. But the tug between traditional and egalitarian models of marriage runs from top to bottom of the class ladder.”
—Arlie Hochschild (20th century)