| Zinc | (english) Chemical Symbol Zn. Element No. 30 of the periodic system; atomic weight 65.38. Blue-white metal; when pure, malleable and ductile even at ordinary temperatures; melting point 787 (degrees) F.; boiling point 1665 (degrees) F., specific gravity 7.14. Can be electrodeposited; it is extensively used as a coating for steel and sheet zinc finds many outlets, such as dry batteries, etc. Zinc-base alloys are of great importance in die casting. Its most important alloy is brass. |
| Zircon | (english) The mineral zircon silicate, ZrSiO4, a very high melting point acid refractory material used as a molding material in steel foundries. |
| Zirconia | (english) ZrO2 an acid refractory up to 2500 B0C (4532 B0F) having good thermal shock resistance and low electrical resistively. |
| Zirconium | (english) Silvery-white, metallic element, mp 1860 B0C (3380 B0F), a powerful deoxidizer when added to molten steel. |
| Brittle: | (english) A brittle structure or material exhibits low ductility, meaning that it exhibits very little inelastic deformation before complete failure. |
| Centroid: | (english) Similar to the concept of center of gravity, except that it applies to a two dimensional shape rather than an object. For a given shape, the centroid location corresponds to the center of gravity for a thin flat plate of that shape, made from a homogeneous material. |
| Component (of a vector): | (english) Any vector can be expressed as a collection of vectors whose sum is equal to the original vector. Each vector in this collection is a component of the original vector. It is common to express a vector in terms of components which are parallel to the x and y axes. |
| Concentrated force: | (english) A force considered to act along a single line in space. Concentrated forces are useful mathematical idealizations, but cannot be found in the real world, where all forces are either body forces acting over a volume or surface forces acting over an area. |
| Connection: | (english) Connection is similar to the concept of support, except that connection refers to a relationship between members in a structural model. A connection restrains degrees of freedom of one member with respect to another. For each restrained degree of freedom, there is a corresponding force transferred from one member to the other; forces associated with unrestrained degrees of freedom are zero. See fixed connection and pin connection. |
| Couple: | (english) A system of forces composed of two equal forces of opposite direction, offset by a distance. A couple is statically equivalent to a moment whose magnitude equals the magnitude of the force times the offset distance. |