Blackened death metalBlackened death metal (also known as black death metal) is an extreme subgenre of heavy metal that fuses elements of black metal and death metal. The genre emerged in early 1990s when black metal bands began incorporating elements of death metal and vice versa. The genre typically employs death growls, tremolo picking, blast beats, and Satanic lyrics and imagery. Bands of the genre typically employ corpse paint, which was adapted from black metal.
MetalA metal (from Ancient Greek μέταλλον métallon 'mine, quarry, metal') is a material that, when freshly prepared, polished, or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well. Metals are typically ductile (can be drawn into wires) and malleable (they can be hammered into thin sheets). These properties are the result of the metallic bond between the atoms or molecules of the metal. A metal may be a chemical element such as iron; an alloy such as stainless steel; or a molecular compound such as polymeric sulfur nitride.
Thrash metalThrash metal (or simply thrash) is an extreme subgenre of heavy metal music characterized by its overall aggression and often fast tempo. The songs usually use fast percussive beats and low-register guitar riffs, overlaid with shredding-style lead guitar work. The lyrical subject matter often includes criticism of The Establishment, opposition to armed conflicts, and at times shares a disdain for the Christian religion with that of black metal. The language is typically direct and denunciatory, an approach borrowed from hardcore punk.
Single-layer materialsIn materials science, the term single-layer materials or 2D materials refers to crystalline solids consisting of a single layer of atoms. These materials are promising for some applications but remain the focus of research. Single-layer materials derived from single elements generally carry the -ene suffix in their names, e.g. graphene. Single-layer materials that are compounds of two or more elements have -ane or -ide suffixes. 2D materials can generally be categorized as either 2D allotropes of various elements or as compounds (consisting of two or more covalently bonding elements).
Christian metalChristian metal, also known as white metal, Jesus metal or heavenly metal, is heavy metal music distinguished by its Christian themed song lyrics and the dedication of the band members to Christianity. Christian metal is typically performed by professed Christians, principally for Christians and is often produced and distributed through various Christian networks. Christian metal bands exist in most of the subgenres of heavy metal music, and the only common link among most Christian metal bands are the lyrics.
Extreme metalExtreme metal is a loosely defined umbrella term for a number of related heavy metal music subgenres that have developed since the early 1980s. It has been defined as a "cluster of metal subgenres characterized by sonic, verbal, and visual transgression". The term usually refers to a more abrasive, harsher, underground, non-commercialized style associated with the speed metal, thrash metal, black metal, death metal, and doom metal genres.
History of the transistorA transistor is a semiconductor device with at least three terminals for connection to an electric circuit. In the common case, the third terminal controls the flow of current between the other two terminals. This can be used for amplification, as in the case of a radio receiver, or for rapid switching, as in the case of digital circuits. The transistor replaced the vacuum-tube triode, also called a (thermionic) valve, which was much larger in size and used significantly more power to operate.
Heavy metal musicHeavy metal (or simply metal) is a genre of rock music that developed in the late 1960s and early 1970s, largely in the United Kingdom and United States. With roots in blues rock, psychedelic rock and acid rock, heavy metal bands developed a thick, monumental sound characterized by distorted guitars, extended guitar solos, emphatic beats and loudness. In 1968, three of the genre's most famous pioneers – Led Zeppelin, Black Sabbath and Deep Purple – were founded. Though they came to attract wide audiences, they were often derided by critics.
Vacuum depositionVacuum deposition , also known as vacuum coating or thin-film deposition, is a group of processes used to deposit layers of material atom-by-atom or molecule-by-molecule on a solid surface. These processes operate at pressures well below atmospheric pressure (i.e., vacuum). The deposited layers can range from a thickness of one atom up to millimeters, forming freestanding structures. Multiple layers of different materials can be used, for example to form optical coatings.
Evaporation (deposition)Evaporation is a common method of thin-film deposition. The source material is evaporated in a vacuum. The vacuum allows vapor particles to travel directly to the target object (substrate), where they condense back to a solid state. Evaporation is used in microfabrication, and to make macro-scale products such as metallized plastic film. Evaporation involves two basic processes: a hot source material evaporates and condenses on the substrate. It resembles the familiar process by which liquid water appears on the lid of a boiling pot.
