Cosy

Cosy can refer to:

See also

CoSy

CoSy can refer to:

See also:

Two-dimensional nuclear magnetic resonance spectroscopy

Two-dimensional nuclear magnetic resonance spectroscopy (2D NMR) is a set of nuclear magnetic resonance spectroscopy (NMR) methods which give data plotted in a space defined by two frequency axes rather than one. Types of 2D NMR include correlation spectroscopy (COSY), J-spectroscopy, exchange spectroscopy (EXSY), and nuclear Overhauser effect spectroscopy (NOESY). Two-dimensional NMR spectra provide more information about a molecule than one-dimensional NMR spectra and are especially useful in determining the structure of a molecule, particularly for molecules that are too complicated to work with using one-dimensional NMR.

The first two-dimensional experiment, COSY, was proposed by Jean Jeener, a professor at the Université Libre de Bruxelles, in 1971. This experiment was later implemented by Walter P. Aue, Enrico Bartholdi and Richard R. Ernst, who published their work in 1976.

Fundamental concepts

Each experiment consists of a sequence of radio frequency (RF) pulses with delay periods in between them. It is the timing, frequencies, and intensities of these pulses that distinguish different NMR experiments from one another. Almost all two-dimensional experiments have four stages: the preparation period, where a magnetization coherence is created through a set of RF pulses; the evolution period, a determined length of time during which no pulses are delivered and the nuclear spins are allowed to freely precess (rotate); the mixing period, where the coherence is manipulated by another series of pulses into a state which will give an observable signal; and the detection period, in which the free induction decay signal from the sample is observed as a function of time, in a manner identical to one-dimensional FT-NMR.

Playa

Playa (plural playas) may refer to:

Landforms

Named playas

Populated places

Playa (band)

Playa is an American R&B-hip-hop group. The original lineup consisted of Jawaan "Smoke" Peacock, Benjamin "Black" Bush and Stephen "Static Major" Garrett. Playa is best known for their 1998 hit album, Cheers 2 U, produced by longtime collaborator Timbaland. Static was notable for being a successful songwriter of hit singles and album tracks for artists such as Ginuwine, Aaliyah, Truth Hurts, Lil Wayne and Brandy.

History

Early years

Jawaan Peacock, Benjamin Bush and Stephen Garrett met in the late 1980s and formed while the guys were still in high school. Smokey and Digital Black met through a mutual friend who thought the guys would sound good together, while Smokey and Static met in church while performing in a gospel group. Alongside other guys, the three men that would eventually form Playa created a group called A Touch of Class.

Joining Swing Mob

As A Touch of Class, the group met DeVante from Jodeci backstage at a concert. They began singing Boyz II Men songs when DeVante asked them if they knew any Jodeci songs. Essentially they impressed DeVante by performing a cappella versions of Jodeci songs backstage after a concert in 1991/1992. The guys were then signed onto DeVante's Swing Mob label with Elektra Records in 1993/94. Magazines such as Vibe and The Source attribute the signing to Static's close friendship with the boss and producers of the DeVante recording label. The group finally became known as Playa after DeVante heard the guys sing and called them "lil playas".

Playa (Ponce)

Barrio Playa, also known as Playa de Ponce, Ponce Playa, or La Playa, is one of the thirty-one barrios that comprise the municipality of Ponce, Puerto Rico. Along with Bucaná, Canas, Vayas, and Capitanejo, Playa is one of the municipality's five coastal barrios. Barrio Playa also incorporates several islands, the largest of which is Caja de Muertos. It was founded in 1831.

Location

Playa is an urban barrio located in the southern region of the municipality, within the limits of the city of Ponce, south of the traditional center of the city at Plaza Las Delicias, and on the shores of the Caribbean Sea. It is located at 17.9839°N 66.6128°W, and it has an elevation of 10 feet. The toponomy, or origin of the name, describes the geographic area the barrio occupies in southern Ponce and facing the Caribbean Sea.

Boundaries

It is bounded on the North by PR-2, on the South by the Caribbean Sea, on the West by Río Matilde, and on the East by Río Bucaná.

In terms of barrio-to-barrio boundaries, Playa is bounded in the North by Canas Urbano and San Anton, in the South by the Caribbean Sea, in the West by Canas, and in the East by Bucaná.