High Quality Content by WIKIPEDIA articles! The pioneers of photography in the Philippines were Western photographers, mostly from Europe. The practice of taking photographs and the opening of the first photo studios in Spanish Philippines, from the 1840s to the 1890s, were driven by the following reasons: photographs were used as a medium of news and information about the colony, as a tool for tourism, as an instrument for anthropology, as a means for asserting social status, as an implement for historical documentation, as a device for communication, as materials for propaganda, and as a source of ideas for illustrations and engravings. The practice of photography in the Philippines was not without the influence and influx of...

ISBN: 978-5-5080-9260-3

High Quality Content by WIKIPEDIA articles! Photoemission Electron microscopy (PEEM, also called photoelectron microscopy, PEM) is a widely used type of emission microscopy. PEEM utilizes local variations in electron emission to generate image contrast. The excitation is usually produced by UV light, synchrotron radiation or X-ray sources. PEEM measures the coefficient indirectly by collecting the emitted secondary electrons generated in the electron cascade that follows the creation of the primary core hole in the absorption process. PEEM is a surface sensitive technique because the emitted electrons originate from a very shallow layer. In physics, this technique is referred to as PEEM, which goes together naturally with low-energy...

ISBN: 978-5-5144-5774-8

High Quality Content by WIKIPEDIA articles! The science of photonics includes the generation, emission, transmission, modulation, signal processing, switching, amplification, and detection/sensing of light. The term photonics thereby emphasizes that photons are neither particles nor waves — they are different in that they have both particle and wave nature. It covers all technical applications of light over the whole spectrum from ultraviolet over the visible to the near-, mid- and far-infrared. Most applications, however, are in the range of the visible and near infrared light. The term photonics developed as an outgrowth of the first practical semiconductor light emitters invented in the early 1960s and optical fibers developed in...

ISBN: 978-5-5144-9055-4

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ISBN: 978-5-5117-5823-7

High Quality Content by WIKIPEDIA articles! Photosystem I (PS I) (or plastocyanin: ferredoxin oxidoreductase) is the second photosystem in the photosynthetic light reactions of algae, plants, and some bacteria. Photosystem I is so named because it was discovered before photosystem II. Aspects of PS I were discovered in the 1950s, but the significances of these discoveries was not yet known. Louis Duysens first proposed the concepts of photosystems I and II in 1960, and, in the same year, a proposal by Fay Bendall and Robert Hill assembled earlier discoveries into a cohesive theory of serial photosynthetic reactions. Hill and Bendall’s hypothesis was later justified in experiments conducted in 1961 by Duysens and Witt groups.

ISBN: 978-5-5082-4690-7

High Quality Content by WIKIPEDIA articles! Photomontage is the process and result of making a composite photograph by cutting and joining a number of other photographs. The composite picture was sometimes photographed so that the final image is converted back into a seamless photographic print. A similar method, although one that does not use film, is realized today through image-editing software. This latter technique is referred to by professionals as "compositing", and in casual usage is often called "photoshopping".

ISBN: 978-5-5111-8003-8

High Quality Content by WIKIPEDIA articles! Photophobia is a symptom of abnormal intolerance to visual perception of light. As a medical symptom photophobia is not a morbid fear or phobia, but an experience of discomfort or pain to the eyes due to light exposure or by presence of actual physical photosensitivity of the eyes, though the term is sometimes additionally applied to abnormal or irrational fear of light such as heliophobia.

ISBN: 978-5-5113-3105-8

High Quality Content by WIKIPEDIA articles! The Photographic Alliance of Great Britain (known as the PAGB) is the umbrella organisation that provides benefits and co-ordinates specific events for the majority of photographic clubs and societies in England, Scotland, Wales & Northern Ireland. (Hence its scope is "the United Kingdom", not just "Great Britain").

ISBN: 978-5-5083-1740-9

High Quality Content by WIKIPEDIA articles! Photochromism is the reversible transformation of a chemical species between two forms by the absorption of electromagnetic radiation, where the two forms have different absorption spectra. Trivially, this can be described as a reversible change of colour upon exposure to light. The phenomenon was discovered in the late 1880s, including work by Markwald, who studied the reversible change of color of 2,3,4,4-tetrachloronaphthalen-1(4H)-one in the solid state. He labeled this phenomenon "phototropy", and this name was used until the 1950s when Yehuda Hirshberg, of the Weizmann Institute of Science in Israel proposed the term "photochromism". Photochromism can take place in both organic and...

ISBN: 978-5-5145-7560-2

High Quality Content by WIKIPEDIA articles! Photojournalism is a particular form of journalism (the collecting, editing, and presenting of news material for publication or broadcast) that creates images in order to tell a news story. It is now usually understood to refer only to still images, but in some cases the term also refers to video used in broadcast journalism. Photojournalism is distinguished from other close branches of photography (i.e., documentary photography, social documentary photography, street photography or celebrity photography) by complying with a rigid ethical framework which demands that the work is both honest and impartial whilst telling the story in strictly journalistic terms. Photojournalists create pictures...

ISBN: 978-5-5110-2466-0

High Quality Content by WIKIPEDIA articles! A photodiode is a type of photodetector capable of converting light into either current or voltage, depending upon the mode of operation. The common, traditional solar cell used to generate electric solar power is a large area photodiode.

ISBN: 978-5-5146-2105-7

High Quality Content by WIKIPEDIA articles! Photobiology is the scientific study of the interactions of light (technically, non-ionizing radiation) and living organisms. The field includes the study of photosynthesis, photomorphogenesis, visual processing, circadian rhythms, bioluminescence, and ultraviolet radiation effects. The division between ionizing radiation and nonionizing radiation is typically considered to be 10 eV, the energy required to ionize an oxygen atom.

ISBN: 978-5-5110-8138-0

High Quality Content by WIKIPEDIA articles! Photosystem II (or water-plastoquinone oxidoreductase) is the first protein complex in the Light-dependent reactions. It is located in the thylakoid membrane of plants, algae, and cyanobacteria. The enzyme uses photons of light to energize electrons that are then transferred through a variety of coenzymes and cofactors to reduce plastoquinone to plastoquinol. The energized electrons are replaced by oxidizing water to form hydrogen ions and molecular oxygen. By obtaining these electrons from water, photosystem II provides the electrons for all of photosynthesis to occur. The hydrogen ions (protons) generated by the oxidation of water help to create a proton gradient that is used by ATP synthase...

ISBN: 978-5-5121-6898-1

High Quality Content by WIKIPEDIA articles! There were a good number of battles and other scenes of the American Civil War, and collectively they have provided the world with a visual first hand account of this otherwise fleeting period in American history. The American Civil War (1861–65) was the fourth war in history to be caught on camera. The first Mexican-American War (1846–48), the Crimean War (1854–56), and the Indian Rebellion of 1857.

ISBN: 978-5-5149-7311-8

High Quality Content by WIKIPEDIA articles! Phrenology is the fifth studio album by American hip hop band The Roots, released November 26, 2002, on Geffen Records and MCA Records. Recording sessions for the album took place during June 2000 to September 2002. It was primarily produced by members of the band and features contributions from hip hop and neo soul artists such as Cody ChesnuTT, Musiq Soulchild, Talib Kweli, and Jill Scott.

ISBN: 978-5-5088-0097-0

High Quality Content by WIKIPEDIA articles! Phylloquinone is a polycyclic aromatic ketone, based on 2-methyl-1,4-naphthoquinone, with a 3-phytyl substituent.

ISBN: 978-5-5113-3296-3

High Quality Content by WIKIPEDIA articles! PhyreEngine (also known as Phyre Engine) is a free to use, cross platform (PC, PSP, PS Vita and PS3) game engine from Sony Computer Entertainment. By 2011 PhyreEngine had been adopted by dozens of game studios "to power almost fifty" games for the PlayStationStore or on Blu-ray Discs.

ISBN: 978-5-5141-3135-8

High Quality Content by WIKIPEDIA articles! The body is largely composed of water molecules which each contain two hydrogen nuclei or protons. When a person goes inside the powerful magnetic field of the scanner, the magnetic moments of these protons align with the direction of the field.

ISBN: 978-5-5091-8833-6

High Quality Content by WIKIPEDIA articles! A physics processing unit (PPU) is a dedicated microprocessor designed to handle the calculations of physics, especially in the physics engine of video games. Examples of calculations involving a PPU might include rigid body dynamics, soft body dynamics, collision detection, fluid dynamics, hair and clothing simulation, finite element analysis, and fracturing of objects. The idea is that specialized processors offload time consuming tasks from a computer`s CPU, much like how a GPU performs graphics operations in the main CPU`s place.

ISBN: 978-5-5110-8343-8

High Quality Content by WIKIPEDIA articles! Phytelephas is a genus containing six species of palms (family Arecaceae), occurring from southern Panama along the Andes to Ecuador, Bolivia and Peru. They are commonly known as ivory palms, ivory-nut palms or tagua palms; their scientific name means "plant elephant". This and the first two of the common names refer to the very hard white endosperm of their seeds (tagua nuts), which resembles elephant ivory.

ISBN: 978-5-5111-3788-9

High Quality Content by WIKIPEDIA articles! The Piaggio P180 Avanti is an Italian twin-engine turboprop aircraft produced by Piaggio Aero. It seats up to nine passengers in a pressurized cabin, and may be flown by one or two pilots.

ISBN: 978-5-5139-3362-5

High Quality Content by WIKIPEDIA articles! The Piasecki VZ-8 Airgeep (company designation PA-59) was a prototype vertical takeoff and landing (VTOL) aircraft developed by Piasecki Helicopter. The Airgeep was developed to fulfill a US Army Transportation Research Command contract for a flying jeep in 1957. The flying jeep was envisioned to be smaller and easier to fly than a helicopter.

ISBN: 978-5-5118-8948-1

High Quality Content by WIKIPEDIA articles! Given a simple polygon constructed on a grid of equal-distanced points (i.e., points with integer coordinates) such that all the polygon`s vertices are grid points, Pick`s theorem provides a simple formula for calculating the area A of this polygon in terms of the number i of lattice points in the interior located in the polygon and the number b of lattice points on the boundary placed on the polygon`s perimeter:

ISBN: 978-5-5116-1220-1

High Quality Content by WIKIPEDIA articles! Picogen is a rendering system for the creation and rendering of artificial terrain, based on ray tracing. It is free software.

ISBN: 978-5-5120-2312-9

High Quality Content by WIKIPEDIA articles! Picosecond ultrasonics is a type of ultrasonics that uses ultra-high frequency ultrasound generated by ultrashort light pulses. It is a non-destructive technique in which picosecond acoustic pulses penetrate into thin films or nanostructures to reveal internal features such as film thickness as well as cracks, delaminations and voids. It can also be used to probe liquids. The technique is also referred to as picosecond laser ultrasonics or laser picosecond acoustics.

ISBN: 978-5-5110-8458-9