enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Impervious surface - Wikipedia

    en.wikipedia.org/wiki/Impervious_surface

    Impervious surface percentage in various cities. The percentage imperviousness, commonly referred to as PIMP in calculations, is an important factor when considering drainage of water. It is calculated by measuring the percentage of a catchment area which is made up of impervious surfaces such as roads, roofs and other paved surfaces.

  3. Surface area - Wikipedia

    en.wikipedia.org/wiki/Surface_area

    A sphere of radius r has surface area 4πr 2.. The surface area (symbol A) of a solid object is a measure of the total area that the surface of the object occupies. [1] The mathematical definition of surface area in the presence of curved surfaces is considerably more involved than the definition of arc length of one-dimensional curves, or of the surface area for polyhedra (i.e., objects with ...

  4. Specific surface area - Wikipedia

    en.wikipedia.org/wiki/Specific_surface_area

    Scratches, represented by triangular-shaped grooves, make the surface area greater. Specific surface area (SSA) is a property of solids defined as the total surface area (SA) of a material per unit mass, [1] (with units of m 2 /kg or m 2 /g). Alternatively, it may be defined as SA per solid or bulk volume [2] [3] (units of m 2 /m 3 or m −1).

  5. Glossary of chemistry terms - Wikipedia

    en.wikipedia.org/wiki/Glossary_of_chemistry_terms

    This glossary of chemistry terms is a list of terms and definitions relevant to chemistry, including chemical laws, diagrams and formulae, laboratory tools, glassware, and equipment. Chemistry is a physical science concerned with the composition, structure, and properties of matter , as well as the changes it undergoes during chemical reactions ...

  6. Polar surface area - Wikipedia

    en.wikipedia.org/wiki/Polar_surface_area

    The polar surface area (PSA) or topological polar surface area (TPSA) of a molecule is defined as the surface sum over all polar atoms or molecules, primarily oxygen and nitrogen, also including their attached hydrogen atoms. PSA is a commonly used medicinal chemistry metric for the

  7. Surface-area-to-volume ratio - Wikipedia

    en.wikipedia.org/wiki/Surface-area-to-volume_ratio

    Graphs of surface area, A against volume, V of the Platonic solids and a sphere, showing that the surface area decreases for rounder shapes, and the surface-area-to-volume ratio decreases with increasing volume. Their intercepts with the dashed lines show that when the volume increases 8 (2³) times, the surface area increases 4 (2²) times.

  8. Pore structure - Wikipedia

    en.wikipedia.org/wiki/Pore_structure

    This definition has been applied in several research to alter flow equations or measure the fluid-fluid interfacial area. [24] [25] The fundamental idea of fractal geometry is where the third definition of surface roughness comes from, [26] in which either modifies the pore surfaces (two-dimensional) or the whole porous medium (three ...

  9. Urban runoff - Wikipedia

    en.wikipedia.org/wiki/Urban_runoff

    Flooded streets in New Orleans Relationship between impervious surfaces and surface runoff Urban runoff is a major cause of urban flooding , the inundation of land or property in a built-up environment caused by rainfall overwhelming the capacity of drainage systems , such as storm sewers . [ 12 ]