Search results
Results from the WOW.Com Content Network
The self-diffusion coefficient of neat water is: 2.299·10 −9 m 2 ·s −1 at 25 °C and 1.261·10 −9 m 2 ·s −1 at 4 °C. [2] Chemical diffusion occurs in a presence of concentration (or chemical potential) gradient and it results in net transport of mass. This is the process described by the diffusion equation.
The concept of diffusion is widely used in many fields, including physics (particle diffusion), chemistry, biology, sociology, economics, statistics, data science, and finance (diffusion of people, ideas, data and price values). The central idea of diffusion, however, is common to all of these: a substance or collection undergoing diffusion ...
Knudsen diffusion, named after Martin Knudsen, is a means of diffusion that occurs when the scale length of a system is comparable to or smaller than the mean free path of the particles involved. An example of this is in a long pore with a narrow diameter (2–50 nm) because molecules frequently collide with the pore wall. [ 1 ]
Reaction–diffusion systems are mathematical models that correspond to several physical phenomena. The most common is the change in space and time of the concentration of one or more chemical substances: local chemical reactions in which the substances are transformed into each other, and diffusion which causes the substances to spread out ...
Simple syrup (also known as sugar syrup, or bar syrup) is a basic sugar-and-water syrup. It is used by bartenders as a sweetener to make cocktails, and as a yeast feeding agent in ethanol fermentation. The ratio of sugar to water is 1:1 by volume for normal simple syrup, but can get up to 2:1 for rich simple syrup. [6]
Date/Time Thumbnail Dimensions User Comment; current: 21:17, 2 May 2008: 626 × 399 (158 KB): Bibi Saint-Pol {{Information |Description= {{en|Simple diffusion, the movement of particles from an area where their concentration is high to an area that has low concentration. one of the diferent ways in wich molecules move in cells.}} |Source=Own work.
Fick's first law relates the diffusive flux to the gradient of the concentration. It postulates that the flux goes from regions of high concentration to regions of low concentration, with a magnitude that is proportional to the concentration gradient (spatial derivative), or in simplistic terms the concept that a solute will move from a region of high concentration to a region of low ...
is the Diffusion coefficient [2] and is the Source term. [3] A portion of the two dimensional grid used for Discretization is shown below: Graph of 2 dimensional plot. In addition to the east (E) and west (W) neighbors, a general grid node P, now also has north (N) and south (S) neighbors.