- published: 25 Jun 2015
- views: 517665665
Combustion /kəmˈbʌs.tʃən/ or burning is a high-temperature exothermic redox chemical reaction between a fuel and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke. Combustion in a fire produces a flame, and the heat produced can make combustion self-sustaining. Combustion is often a complicated sequence of elementary radical reactions. Solid fuels, such as wood, first undergo endothermic pyrolysis to produce gaseous fuels whose combustion then supplies the heat required to produce more of them. Combustion is often hot enough that light in the form of either glowing or a flame is produced. A simple example can be seen in the combustion of hydrogen and oxygen into water vapor, a reaction commonly used to fuel rocket engines. This reaction releases 242 kJ/mol of heat and reduces the enthalpy accordingly (at constant temperature and pressure):
Combustion of an organic fuel in air is always exothermic because the double bond in O2 is much weaker than other double bonds or pairs of single bonds, and therefore the formation of the stronger bonds in the combustion products CO2 and H2O results in the release of energy. The bond energies in the fuel play only a minor role, since they are similar to those in the combustion products; e.g., the sum of the bond energies of CH4 is nearly the same as that of CO2. The heat of combustion is approximately -418 kJ per mole of O2 used up in the combustion reaction, and can be estimated from the elemental composition of the fuel.
Dance is a performance art form consisting of purposefully selected sequences of human movement. This movement has aesthetic and symbolic value, and is acknowledged as dance by performers and observers within a particular culture. Dance can be categorized and described by its choreography, by its repertoire of movements, or by its historical period or place of origin.
An important distinction is to be drawn between the contexts of theatrical and participatory dance, although these two categories are not always completely separate; both may have special functions, whether social, ceremonial, competitive, erotic, martial, or sacred/liturgical. Others disciplines of human movement are sometimes said to have a dance-like quality, including martial arts, gymnastics, figure skating, synchronized swimming and many other forms of athletics.
Theatrical dance, also called performance or concert dance, is intended primarily as a spectacle, usually a performance upon a stage by virtuoso dancers. It often tells a story, perhaps using mime, costume and scenery, or else it may simply interpret the musical accompaniment, which is often specially composed. Examples are western ballet and modern dance, Classical Indian dance and Chinese and Japanese song and dance dramas. Most classical forms are centred upon dance alone, but performance dance may also appear in opera and other forms of musical theatre.
A glitch is a short-lived fault in a system. It is often used to describe a transient fault that corrects itself, and is therefore difficult to troubleshoot. The term is particularly common in the computing and electronics industries, and in circuit bending, as well as among players of video games, although it is applied to all types of systems including human organizations and nature.
Some reference books, including Random House's American Slang, claim that the term comes from the German word glitschen ("to slip") and the Yiddish word gletshn ("to slide or skid"). Either way it is a relatively new term, as on July 23, 1965, Time Magazine felt it necessary to define it in an article: "Glitches—a spaceman's word for irritating disturbances." In relation to the reference by Time Magazine, the term has been believed to enter common usage during the American Space Race of the 1950s, where it was used to describe minor faults in the rocket hardware that were difficult to pinpoint.
A remix is a piece of media which has been altered from its original state by adding, removing, and/or changing pieces of the item. A song, piece of artwork, book, video, or photograph can all be remixes. The only characteristic of a remix is that it appropriates and changes other materials to create something new.
Most commonly, remixes are associated with music and songs. Songs are remixed for a variety of reasons:
Mo or MO may refer to: