Search results
Results from the WOW.Com Content Network
Calculation of surface energy from first principles (for example, density functional theory) is an alternative approach to measurement. Surface energy is estimated from the following variables: width of the d-band, the number of valence d-electrons, and the coordination number of atoms at the surface and in the bulk of the solid. [5] [page needed]
As an example, wine may exhibit a visible effect called "tears of wine". The effect is a consequence of the fact that alcohol has a lower surface tension and higher volatility than water. The water/alcohol solution rises up the surface of the glass lowering the surface energy of the glass. Alcohol evaporates from the film leaving behind liquid ...
Comparison of surface energy, creating new surface on the left, and surface stress due to elastic deformation. Surface stress was first defined by Josiah Willard Gibbs [1] (1839–1903) as the amount of the reversible work per unit area needed to elastically stretch a pre-existing surface. Depending upon the convention used, the area is either ...
Surface modification is the act of modifying the surface of a material by bringing physical, chemical or biological characteristics different from the ones originally found on the surface of a material. [1] This modification is usually made to solid materials, but it is possible to find examples of the modification to the surface of specific ...
When a soap bubble is in contact with a solid or a liquid surface wetting is observed. On a solid surface, the contact angle of the bubble depends on the surface energy of the solid., [7] [8] A soap bubble has a larger contact angle on a solid surface displaying ultrahydrophobicity than on a hydrophilic surface – see Wetting. On a liquid ...
When a tube of a narrow bore, often called a capillary tube, is dipped into a liquid and the liquid wets the tube (with zero contact angle), the liquid surface inside the tube forms a concave meniscus, which is a virtually spherical surface having the same radius, r, as the inside of the tube. The tube experiences a downward force of magnitude ...
Radiant energy – (≥0), energy of electromagnetic radiation including light and of gravitational radiation; Renewable energy – energy from renewable natural resources that are replenished on a human timescale; Rest energy – (≥0) given by E = mc 2, where m is an object's rest mass; Solar energy; Surface energy; Sustainable energy
Gibbs emphasized that for solids, the surface free energy may be completely different from surface stress (what he called surface tension): [14]: 315 the surface free energy is the work required to form the surface, while surface stress is the work required to stretch the surface. In the case of a two-fluid interface, there is no distinction ...