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Dry chemical powder is used on all classes of fires. Dry chemical powder puts out the fire by coating the burning material with a thin layer of dust, thereby separating the fuel from the oxygen in the air. The powder also works to interrupt the chemical reaction of fire, so these extinguishers are extremely effective at putting out the fire.
Vertex distance is the distance between the back surface of a corrective lens, i.e. glasses (spectacles) or contact lenses, and the front of the cornea. Increasing or decreasing the vertex distance changes the optical properties of the system, by moving the focal point forward or backward, effectively changing the power of the lens relative to ...
Granulometry. In granulometry, the particle-size distribution ( PSD) of a powder, or granular material, or particles dispersed in fluid, is a list of values or a mathematical function that defines the relative amount, typically by mass, of particles present according to size. [ 1] Significant energy is usually required to disintegrate soil, etc ...
The caesium chloride structure adopts a primitive cubic lattice with a two-atom basis, where both atoms have eightfold coordination. The chloride atoms lie upon the lattice points at the corners of the cube, while the caesium atoms lie in the holes in the center of the cubes; an alternative and exactly equivalent 'setting' has the caesium ions at the corners and the chloride ion in the center.
The carbon equivalent is a measure of the tendency of the weld to form martensite on cooling and to suffer brittle fracture. When the carbon equivalent is between 0.40 and 0.60 weld preheat may be necessary. When the carbon equivalent is above 0.60, preheat is necessary, postheat may be necessary. The following carbon equivalent formula is used ...
For the dry bulk density, the sample is oven dried and weighed, giving the mass of soil solids, M s. The relationship between these two masses is M t = M s + M l, where M l is the mass of substances lost on oven drying (often, mostly water). The dry and wet bulk densities are calculated as Dry bulk density = mass of soil/ volume as a whole
A vertex of an angle is the endpoint where two lines or rays come together. In geometry, a vertex (pl.: vertices or vertexes) is a point where two or more curves, lines, or edges meet or intersect. As a consequence of this definition, the point where two lines meet to form an angle and the corners of polygons and polyhedra are vertices. [1] [2] [3]
Armstrong's mixture. Armstrong's mixture is a highly shock and friction sensitive [ 1] primary explosive. Formulations vary, but one consists of 67% potassium chlorate, 27% red phosphorus, 3% sulfur, and 3% calcium carbonate. [ 2][ 3] It is named for Sir William Armstrong, who invented it sometime prior to 1872 for use in explosive shells. [ 4]