Cheap

Cheap may refer to:

Generic top-level domain

Generic top-level domains (gTLDs) are one of the categories of top-level domains (TLDs) maintained by the Internet Assigned Numbers Authority (IANA) for use in the Domain Name System of the Internet. A top-level domain is the last label of every fully qualified domain name. They are called generic for historic reasons; initially, they were contrasted with country-specific TLDs in RFC 920.

The core group of generic top-level domains consists of the com, info, net, and org domains. In addition, the domains biz, name, and pro are also considered generic; however, these are designated as restricted, because registrations within them require proof of eligibility within the guidelines set for each.

Historically, the group of generic top-level domains included domains, created in the early development of the domain name system, that are now sponsored by designated agencies or organizations and are restricted to specific types of registrants. Thus, domains edu, gov, int, and mil are now considered sponsored top-level domains, much like the themed top-level domains (e.g., jobs). The entire group of domains that do not have a geographic or country designation (see country-code top-level domain) is still often referred to by the term generic TLDs.

Cheap (ward)

Coordinates: 51°30′53″N 0°05′38″W / 51.5148°N 0.094°W / 51.5148; -0.094

Cheap is a small ward in the City of London. It stretches west to east from King Edward Street, the border with Farringdon Within ward, to Old Jewry, which adjoins Walbrook; and north to south from Gresham Street, the border with Aldersgate and Bassishaw wards, to Cheapside, the boundary with Cordwainer and Bread Street wards. The name Cheap derives from the Old English word "chep" for "market".

The following roads run north to south across the ward: St. Martin's Le Grand,Foster Lane, Gutter Lane, Wood Street, Milk Street, King Street, and Ironmonger Lane. Within its boundaries are two Anglican churches: St Vedast Foster Lane and St Lawrence Jewry; a third church, St Mildred, Poultry, was demolished in 1872. Several Livery Halls are located in Cheap, including those of the Mercers', Goldsmiths', Wax Chanders' and Saddlers' Companies.

A small part of the Guildhall lies within the ward's boundaries: the main entrance and main hall itself; the remainder is in Bassishaw. Also within Cheap are the Lord Mayor's and City of London Court and the southern end of Basinghall Street.

Kayser

Kayser may refer to:

See also

Kayser (surname)

Kayser is a surname derived from the German imperial title Kaiser (English: emperor). The title Kaiser is in turn derived from the Latin title Caesar, which again is a derivation from the personal name of a branch of the gens (clan) Julia, to which belonged Gaius Julius Caesar, the forebear of the first Roman imperial family. The further etymology is unclear. Other names with the same origin are Kaiser and Keiser; Keyser is more common as a Dutch spelling, and Qaisar is an Arabic version.

Wavenumber

In the physical sciences, the wavenumber (also wave number) is the spatial frequency of a wave, either in cycles per unit distance or radians per unit distance. It can be envisaged as the number of waves that exist over a specified distance (analogous to frequency being the number of cycles or radians per unit time).

In multidimensional systems, the wavenumber is the magnitude of the wave vector. The space of wave vectors is called reciprocal space. Wave numbers and wave vectors play an essential role in optics and the physics of wave scattering, such as X-ray diffraction, neutron diffraction, and elementary particle physics.

For quantum mechanical waves, wavenumber multiplied by Planck's constant is the canonical momentum.

Wavenumber can be used to specify quantities other than spatial frequency. In optical spectroscopy, it is often used as a unit of temporal frequency assuming a certain speed of light. In this context, it is the number of cycles—not radians—per unit length, and the reference distance should be assumed to be cm. In the same domain, wavenumber can also be used as a unit of energy; 1 cm⁻¹ of energy is the amount of energy in a single photon with a wavelength of 1 cm, the conversion being done using Planck's relation. For example, 1 cm⁻¹ implies 1.23984×10⁻⁴ eV and 8065.54 cm⁻¹ implies 1 eV.

Adhesive

Adhesive may be used interchangeably with glue, cement, mucilage, or paste, and is any substance applied to one surface, or both surfaces, of two separate items that binds them together and resists their separation. Adjectives may be used in conjunction with the word “adhesive” to describe properties based on the substance's physical or chemical form, the type of materials joined, or conditions under which it is applied.

The use of adhesives offers many advantages over binding techniques such as sewing, mechanical fastening, thermal bonding, etc. These include the ability to bind different materials together, to distribute stress more efficiently across the joint, the cost effectiveness of an easily mechanized process, an improvement in aesthetic design, and increased design flexibility. Disadvantages of adhesive use include decreased stability at high temperatures, relative weakness in bonding large objects with a small bonding surface area, and greater difficulty in separating objects during testing. Adhesives are typically organized by the method of adhesion. These are then organized into reactive and non-reactive adhesives, which refers to whether the adhesive chemically reacts in order to harden. Alternatively they can be organized by whether the raw stock is of natural or synthetic origin, or by their starting physical phase.