thesIt » density http://lakm.us/thesit computer science research log in semi microbloging style Tue, 24 Aug 2010 21:34:55 +0000 http://wordpress.org/?v=2.9 en hourly 1 Density of a material is defined as its … http://lakm.us/thesit/305/density-of-a-material-is-defined-as-its/ http://lakm.us/thesit/305/density-of-a-material-is-defined-as-its/#comments Sun, 22 Aug 2010 06:32:12 +0000 Arif http://xp-racy.lan/s2/?p=305 Density of a material is defined as its mass per unit volume.
ρ (in some countries i.e. USA) is also defined as weight per unit volume
Units: (kg/m³), g/cm³

]]> http://lakm.us/thesit/305/density-of-a-material-is-defined-as-its/feed/ 0 Interfacial tension and centrifugal forc … http://lakm.us/thesit/231/interfacial-tension-and-centrifugal-forc/ http://lakm.us/thesit/231/interfacial-tension-and-centrifugal-forc/#comments Fri, 19 Feb 2010 12:06:03 +0000 Arif http://xp-racy.lan/s2/?p=231 Interfacial tension and centrifugal forces balanced at mechanical equilibrium.

centrifugal-IFT equilibrium

centrifugal-IFT equilibrium

Interfacial tension of any liquid that gives a shape very close to a cylinder at the equilibrium point, can be estimated using Vonnegut’s expression:

\sigma=\frac{\Delta\rho\omega^2}{4}R^3

ω : angular velocity; (radians per second, degrees per second, revolutions per second)

Δρ : difference between two fluid: the less-dense and the dense

]]> http://lakm.us/thesit/231/interfacial-tension-and-centrifugal-forc/feed/ 0 Statistical Mechanics Basis of Macleod http://lakm.us/thesit/214/statistical-mechanics-basis-of-macleodae/ http://lakm.us/thesit/214/statistical-mechanics-basis-of-macleodae/#comments Thu, 18 Feb 2010 21:23:39 +0000 Arif http://xp-racy.lan/s2/?p=214 Statistical Mechanics Basis of Macleod’s Formula. M.-E. BOUDH-HIR and G.A. MANSOORI. Journal of Physical Chemistry, Volume 94, pp.8362-8364, 1990.

The famous formula of Macleod, relating the surface tension of a liquid in equilibrium with its own vapor to the one-particle densities in the two phases of the system, is derived. Proved using the statistical- mechanical definition of the surface tension.

(Later on Mansoori worked with Escobedo)

StatMechBasisOfMcLeodEquation.pdf

]]> http://lakm.us/thesit/214/statistical-mechanics-basis-of-macleodae/feed/ 0 The proposed 1996: relating the surface … http://lakm.us/thesit/154/the-proposed-1996-relating-the-surface/ http://lakm.us/thesit/154/the-proposed-1996-relating-the-surface/#comments Fri, 01 Jan 2010 18:19:05 +0000 Arif http://xp-racy.lan/s2/?p=154 Escobedo and Mansoori (AIChE J. 42(5): 1425, 1996) Found original paper: check Escobedo 1996

The proposed 1996 paper relates the surface tension of mixtures to bulk-phase concentrations and properties (i.e. densities). Surface tension of pure organic fluids σ:

\sigma=[P(\rho_l-\rho_v)^4]

The two ρ are densities: liquid and vapour.

They introduced parachor (P), a new expression, derived from statistical mechanics (from Macleod equation) which represents the experimental surface tension of 94 different organic compounds within 1.05 AAD% (average absolute deviations).

(Kumar 2005) It expresses the surface tension of a liquid in equilibrium with its own vapour. Historical reference for parachor cited here: Macleod, Sugden, Quayle, Escobedo.

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