20 Y.O.

20 Y.O. is the ninth studio album by American singer-songwriter Janet Jackson. It was released on September 20, 2006 by Virgin Records. Its title references her third studio album, Control (1986), which commemorated its twentieth release anniversary in 2006. The release would represent Control's "celebration of the joyful liberation and history-making musical style". For the project, Jackson enlisted a variation of producers to work with her, including LRoc, Manuel Seal, The Avila Brothers and No I.D., in addition to her longtime partners Jimmy Jam and Terry Lewis and then-boyfriend Jermaine Dupri. Its musical style globalizes R&B and dance music.

20 Y.O. received mixed reviews from music critics, with many of them chastising the production and involvement of Dupri. The album debuted at number two on the Billboard 200, making it Jackson's eighth consecutive top three debut and second consecutive number two album debut. The Recording Industry Association of America (RIAA) certified it platinum, becoming Jackson's eighth consecutive platinum album. Internationally, the album failed to make an impact on charts, reaching the top sixty in Australia and number 43 on European charts. Worldwide the album has sold 1.2 million copies. 20 Y.O. earned a Grammy Award nomination for Best Contemporary R&B Album in 2007.

Yo (disambiguation)

Yo is an interjection meaning "hello" or "hey".

Yo may also refer to:

Language

Music

Other uses

See also

Yo

Yo is an English slang interjection, commonly associated with American English. It was popularized after being used commonly in Philadelphia, Pennsylvania since the 1940s.

Although often used as a greeting, yo may come at the end of a sentence, often to direct focus onto a particular individual or group or to gain the attention of another individual or group. It may specify that a certain statement that had been uttered is more important, or may just be an "attention grabber".

Etymology and history

The interjection yo was first used in Middle English. The Middle English term originated from Old English ġēa ("yes") In addition to yo, it was also sometimes written io.

Though the term may have been in use in the 16th century, its current popularity stems from its use in Philadelphia's Italian American population in the twentieth century, which spread to other ethnic groups in the city, notably among the African Americans.

From the late twentieth century it frequently appeared in hip hop music and became associated with African American Vernacular English, as seen in the title Yo! MTV Raps, a popular American television hip-hop music program in the 1990s.

Yttrium(III) oxide

Yttrium oxide, also known as yttria, is Y₂O₃. It is an air-stable, white solid substance. Yttrium oxide is used as a common starting material for both materials science as well as inorganic compounds.

Uses

Materials science

It is the most important yttrium compound and is widely used to make Eu:YVO₄ and Eu:Y₂O₃phosphors that give the red color in color TV picture tubes. Yttrium oxide is also used to make yttrium iron garnets, which are very effective microwave filters.

Y₂O₃ is used to make the high temperature superconductor YBa₂Cu₃O₇, known as "1-2-3" to indicate the ratio of the metal constituents:

This synthesis is typically conducted at 800 °C.

The thermal conductivity of yttrium oxide is 27 W/(m·K).

Inorganic synthesis

Yttrium oxide is an important starting point for inorganic compounds. For organometallic chemistry it is converted to YCl₃ in a reaction with concentrated hydrochloric acid and ammonium chloride.

Lasers

Y₂O₃ is a prospective solid-state laser material. In particular, lasers with ytterbium as dopant allow the efficient operation both in continuous operation and in pulsed regimes. At high concentration of excitations (of order of 1%) and poor cooling, the quenching of emission at laser frequency and avalanche broadband emission takes place.