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Comet Encke
Comet Encke , or Encke's Comet (official designation: 2P/Encke), is a periodic comet that completes an orbit of the Sun once every 3.3 years. (This is the shortest period of a reasonably bright comet; the faint main-belt comet 311P/PanSTARRS has a period of 3.2 years.) Encke was first recorded by Pierre Méchain on 17 January 1786, but it was not recognized as a periodic comet until 1819 when its orbit was computed by Johann Franz Encke. Like Halley's Comet, it is unusual in its being named after the calculator of its orbit rather than its discoverer. Like most comets, it has a very low albedo, reflecting only 4.6% of the light its comet nucleus, nucleus receives, although comets generate a large coma (cometary), coma and tail that can make them much more visible during their perihelion (closest approach to the Sun). The diameter of the nucleus of Encke's Comet is 4.8 km. Discovery As its official designation implies, Encke's Comet was the first periodic comet discovered af ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Two-photon Excitation Microscopy
Two-photon excitation microscopy (TPEF or 2PEF) is a fluorescence imaging technique that is particularly well-suited to image scattering living tissue of up to about one millimeter in thickness. Unlike traditional fluorescence microscopy, where the excitation wavelength is shorter than the emission wavelength, two-photon excitation requires simultaneous excitation by two photons with longer wavelength than the emitted light. The laser is focused onto a specific location in the tissue and scanned across the sample to sequentially produce the image. Due to the non-linearity of two-photon excitation, mainly fluorophores in the micrometer-sized focus of the laser beam are excited, which results in the spatial resolution of the image. This contrasts with confocal microscopy, where the spatial resolution is produced by the interaction of excitation focus and the confined detection with a pinhole. Two-photon excitation microscopy typically uses near-infrared (NIR) excitation light ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LMS Class 2P 4-4-0
The London, Midland and Scottish Railway Class 2P 4-4-0 was a class of steam locomotive designed for light passenger work. Overview The class was introduced in 1928 and was a Railways Act 1921, post-grouping development of the Midland Railway 483 Class with modified dimensions and reduced boiler mountings. The numbering continued from where the Midland engines left off at 563 and eventually reached 700. 138 were built, though numbering is slightly complicated by renumberings and transfers. Details Numbers 633 and 653 were fitted with Dabeg feedwater heater in 1933. Numbers 591 and 639 were withdrawn in 1934 after being heavily damaged in an accident at Port Eglinton Junction near Cumberland Street Station, Glasgow on 6 September of the same year. After nationalisation in 1948, British Railways added 40000 to the numbers of the remaining 136 engines. Further withdrawals came between 1954 and 1962. All were scrapped. Models Hornby Railways, Hornby produce a 00 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2P Reserves
Proven reserves (also called measured reserves, 1P, and reserves) is a measure of fossil fuel energy reserves, such as oil and gas reserves and coal reserves. It is defined as the "quantity of energy sources estimated with reasonable certainty, from the analysis of geologic and engineering data, to be recoverable from well established or known reservoirs with the existing equipment and under the existing operating conditions." A reserve is considered proven if it is probable that at least 90% of the resource is recoverable by economically profitable means. Operating conditions are taken into account when determining if a reserve is classified as proven. Operating conditions include operational break-even price, regulatory and contractual approvals, without which the reserve cannot be classified as proven. Price changes therefore can have a large impact on the classification of proven reserves. Regulatory and contractual conditions may change, and also affect the amount of proven ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2 Pistols
Jeremy Lemont Saunders (born June 11, 1983), better known by his stage name 2 Pistols (censored as 2P), is an American rapper. After the local success of his independent single "Dirty Foot", he signed a record deal with Universal Republic Records in 2007. In January 2008, he released his debut single, " She Got It" (featuring T-Pain and Tay Dizm), which peaked at number 24 on the ''Billboard'' Hot 100. The song preceded his debut studio album, '' Death Before Dishonor'' (2008), which saw moderate critical and commercial reception and no further mainstream recognition with its follow–ups. Biography Saunders grew up in a broken home, with his extended family looking after him. In his teens, Saunders became involved in local crime, and in 2005, he was incarcerated for eight months. After this, he became involved in music promotion and formed a group called Blood Money Union, which consisted of other DJs, producers, and rappers. Saunders' first success in rapping came with a sel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Two-photon Absorption
In atomic physics, two-photon absorption (TPA or 2PA), also called two-photon excitation or non-linear absorption, is the (almost) simultaneous Absorption (electromagnetic radiation), absorption of two photons of identical or different frequencies in order to Electron excitation, excite an atom or a molecule from one state (usually the ground state), via a virtual energy level, to a higher energy, most commonly an excited electronic state. Absorption of two photons with the same frequency is called degenerate two-photon absorption, while absorption of two photons with different frequencies is called non-degenerate two-photon absorption. The energy difference between the involved lower and upper states is equal or smaller than the sum of the photon energy, photon energies of the two photons absorbed. Since TPA depends on the simultaneous absorption of two photons, the probability of two-photon absorption is proportional to the photon dose (), which is proportional to the square of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Airphil Express
Air Philippines Corporation, operating as PAL Express and formerly branded as Air Philippines and Airphil Express, is a wholly-owned subsidiary of Philippine Airlines. It is PAL's regional brand, with services from its hubs in Manila, Clark, Cebu, and Davao. The airline was rebranded a number of times - first as Air Philippines, then Airphil Express, and finally as PAL Express. After a series of financial losses, Air Philippines ceased operations until it was acquired by investors from Philippine Airlines. After the acquisition, the airline was re-launched as PAL Express, operating some routes and slot assignments of its sister company Philippine Airlines until its management decided to rebrand the carrier as a budget airline known as Airphil Express. However, in March 2013, the airline name reverted to PAL Express. As a codeshare partner of Philippine Airlines, PAL Express operates as a full-service carrier within a low-cost business model. PAL Express is Philippine Airlines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atomic Orbital
In quantum mechanics, an atomic orbital () is a Function (mathematics), function describing the location and Matter wave, wave-like behavior of an electron in an atom. This function describes an electron's Charge density, charge distribution around the Atomic nucleus, atom's nucleus, and can be used to calculate the probability of finding an electron in a specific region around the nucleus. Each orbital in an atom is characterized by a set of values of three quantum numbers , , and , which respectively correspond to electron's energy, its angular momentum, orbital angular momentum, and its orbital angular momentum projected along a chosen axis (magnetic quantum number). The orbitals with a well-defined magnetic quantum number are generally complex-valued. Real-valued orbitals can be formed as linear combinations of and orbitals, and are often labeled using associated Spherical harmonics#Harmonic polynomial representation, harmonic polynomials (e.g., ''xy'', ) which describe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Artillery By Country
This list contains all artillery systems organized primarily by their country of origin. In cases where multiple countries collaborated on a project, a system could be listed under each of the major participants. Also, in outstanding cases where a system was adopted fully by another country, the system may be listed there also. This list is not an attempt to list every artillery system ever used by each country. : ''Jump to a specific country in the table below.'' __NOTOC__ Albania ; Mortars * Hirtenberger M6 * Hirtenberger M8 * PM43 * Type 67 Argentina ; Field artillery * Model 1968 105 mm model 1968 recoilless gun * CITEFA Model 77 Cold War/modern 155 mm gun/howitzer, based on the French 155 mm gun mounted on AMX Mk F3 SP gun * CALA 30 155 mm L45 long range gun ; Self-propelled field artillery * VCA 155 self-propelled 155 mm howitzer, based on a TAM chassis with a Palmaria turret ; Rocket artillery * SLAM Pampero 105 mm multiple ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fandoms
A fandom is a subculture composed of fans characterized by a feeling of camaraderie with others who share a common interest. Fans typically are interested in even minor details of the objects of their fandom and spend a significant portion of their time and energy involved with their interest, often as a part of a social network with particular practices, differentiating fandom-affiliated people from those with only a casual interest. A fandom can grow around any area of human interest or activity. The subject of fan interest can be narrowly defined, focused on something like a franchise or an individual celebrity, or encompassing entire hobbies, genres or fashions. While it is now used to apply to groups of people fascinated with any subject, the term has its roots in those with an enthusiastic appreciation for sports. Merriam-Webster's dictionary traces the usage of the term back as far as 1903. Many fandoms are overlapped. There are a number of large conventions that cate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromosome 2 (human)
Chromosome 2 is one of the twenty-three pairs of chromosomes in humans. People normally have two copies of this chromosome. Chromosome 2 is the second-largest human chromosome, spanning more than 242 million base pairs and representing almost eight percent of the total DNA in human cells. Chromosome 2 contains the HOXD homeobox gene cluster. Fusion Humans have only twenty-three pairs of chromosomes, while all other extant members of Hominidae have twenty-four pairs. It is believed that Neanderthals and Denisovans had twenty-three pairs. Human chromosome 2 is a result of an end-to-end fusion of two ancestral chromosomes.It has been hypothesized that Human Chromosome 2 is a fusion of two ancestral chromosomes by Alec MacAndrew; accessed 18 May 2006. The ev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Two Pence (British Decimal Coin)
The British decimal two pence coin (often shortened to 2p in writing and speech) is a denomination of sterling coinage equalling of a pound. Since the coin's introduction on 15 February 1971, the year British currency was decimalised, its obverse has featured four profiles of Queen Elizabeth II. In 2008 the design on its reverse changed from the original depiction of a plume of ostrich feathers with a coronet to a segment of the Royal Shield. The two pence coin was originally minted from bronze, but changed in 1992 to copper-plated steel. As of March 2014 there were an estimated 6.55 billion 2p coins in circulation, corresponding to a value of £131 million. Two pence coins are legal tender for amounts only up to the sum of 20p when offered in repayment of a debt; however, the coin's legal tender status is not normally relevant for everyday transactions. Composition From its first minting in 1971 until 1992, two pence coins were made from bronze. In 1992, this was changed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
