Ad
related to: how does foam form
Search results
Results From The WOW.Com Content Network
All types of foam are widely used as core material in sandwich-structured composite materials. The earliest known engineering use of cellular solids is with wood, which in its dry form is a closed-cell foam composed of lignin, cellulose, and air. From the early 20th century, various types of specially manufactured solid foams came into use.
Foam fractionation proceeds via two mechanisms: The target molecule adsorbs to a bubble surface, and; The bubbles form a foam which travels up a column and is discharged to the foamate stream of foam fractionation. The rate at which certain non-ionic molecules can adsorb to bubble surface can be estimated by solving the Ward-Tordai equation. [4]
Wet foam tends to form at the lower portion of the foam column, while dry foam tends to form at the upper portion. The wet foam is more spherical and viscous, and the dry foam tends to be larger in diameter and less viscous. [1] Wet foam forms closer to the originating liquid, while dry foam develops at the outer boundaries. As such, what most ...
Firefighting foam is a foam used for fire suppression. Its role is to cool the fire and to coat the fuel, preventing its contact with oxygen, thus achieving suppression of the combustion. Firefighting foam was invented by the Moldovan engineer and chemist Aleksandr Loran in 1902. [1] The surfactants used must produce foam in concentrations of ...
Sea foam washed up or blown onto a beach. Sea foam, ocean foam, beach foam, or spume is a type of foam created by the agitation of seawater, particularly when it contains higher concentrations of dissolved organic matter (including proteins, lignins, and lipids) derived from sources such as the offshore breakdown of algal blooms. [1]
An assortment of polyurethane foam products for cushioning and insulation. Polyurethane foam is a solid polymeric foam based on polyurethane chemistry. As a specialist synthetic material with highly diverse applications, polyurethane foams are primarily used for thermal insulation and as a cushioning material in mattresses, upholstered furniture or as seating in vehicles.
Although it is a closed-cell foam, both expanded and extruded polystyrene are not entirely waterproof or vapor proof. [58] In expanded polystyrene there are interstitial gaps between the expanded closed-cell pellets that form an open network of channels between the bonded pellets, and this network of gaps can become filled with liquid water.
The generalised chemical structure of polyisocyanurate showing the isocyanurate group. The polyols are abbreviated as R-groups.. Polyisocyanurate (/ ˌ p ɒ l ɪ ˌ aɪ s oʊ s aɪ ˈ æ nj ʊər eɪ t /), also referred to as PIR, polyol, or ISO, is a thermoset plastic [1] typically produced as a foam and used as rigid thermal insulation.