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Voltaic pile

The voltaic pile was the first electrical battery that could continuously provide an electric current to a circuit. It was invented by Italian physicist Alessandro Volta, who published his experiments in 1799; the voltaic pile enabled a rapid series of other discoveries including the electrical decomposition of water into oxygen and hydrogen by William Nicholson and Anthony Carlisle and the discovery or isolation of the chemical elements sodium, calcium, barium and magnesium by Humphry Davy. The entire 19th-century electrical industry was powered by batteries related to Volta's until the advent of the dynamo in the 1870s. Volta's invention was built on Luigi Galvani's 1780s discovery of how a circuit of two metals and a frog's leg can cause the frog's leg to respond. Volta demonstrated in 1794 that when two metals and brine-soaked cloth or cardboard are arranged in a circuit they produce an electric current. In 1800, Volta stacked several pairs of alternating copper and zinc discs separated by cloth or cardboard soaked in brine to increase the electrolyte conductivity.

When the top and bottom contacts were connected by a wire, an electric current flowed through the voltaic pile and the connecting wire. On 20 March 1800, Alessandro Volta wrote to the London Royal Society to describe the technique for producing electric current using his device. On learning of the voltaic pile, William Nicholson and Anthony Carlisle used it to discover the electrolysis of water. Humphry Davy showed that the electromotive force, which drives the electric current through a circuit containing a single voltaic cell, was caused by a chemical reaction, not by the voltage difference between the two metals, he used the voltaic pile to decompose chemicals and to produce new chemicals. William Hyde Wollaston showed that electricity from voltaic piles had identical effects to those of electricity produced by friction. In 1802 Vasily Petrov used voltaic piles in the research of electric arc effects. Humphry Davy and Andrew Crosse were among the first to develop large voltaic piles. Davy used a 2000-pair pile made for the Royal Institution in 1808 to demonstrate carbon arc discharge and isolate five new elements: barium, boron and magnesium.

Because Volta believed that the electromotive force occurred at the contact between the two metals, Volta's piles had a different design than the modern design illustrated on this page. His piles had one extra disc of copper at the top, in contact with the zinc, one extra disc of zinc at the bottom, in contact with the copper. Expanding on Volta's work and the electro-magnetism work of his mentor Humphry Davy, Michael Faraday utilized both magnets and the voltaic pile in his experiments with electricity. Faraday believed that all "electricities" being studied at the time were the same, his work to prove this theory led him to propose two laws of electrochemistry which stood in direct conflict with the current scientific beliefs of the day as laid down by Volta thirty years earlier. Because of their contributions to the understanding of this field of study and Volta are both considered to be among the fathers of electrochemistry; the words "electrode" and "electrolyte", used above to describe Volta's work, are due to Faraday.

A number of high-voltage dry piles were invented between the early 19th century and the 1830s in an attempt to determine the source of electricity of the wet voltaic pile, to support Volta's hypothesis of contact tension. Indeed, Volta himself experimented with a pile whose cardboard discs had dried out, most accidentally; the first to publish was Johann Wilhelm Ritter in 1802, albeit in an obscure journal, but over the next decade, it was announced as a new discovery. One form of dry pile is the Zamboni pile. Francis Ronalds in 1814 was one of the first to realise that dry piles worked through chemical reaction rather than metal to metal contact though corrosion was not visible due to the small currents generated; the dry pile could be referred to as the ancestor of the modern dry cell. The strength of the pile is expressed in terms of emf, given in volts. Alessandro Volta's theory of contact tension considered that the emf, which drives the electric current through a circuit containing a voltaic cell, occurs at the contact between the two metals.

Volta did not consider the electrolyte, brine in his experiments, to be significant. However, chemists soon realized that water in the electrolyte was involved in the pile's chemical reactions, led to the evolution of hydrogen gas from the copper or silver electrode; the modern, atomic understanding of a cell with zinc and copper electrodes separated by an electrolyte is the following. When the cell is providing an electrical current through an external circuit, the metallic zinc at the surface of the zinc anode is oxidised and dissolves into the electrolyte as electrically charged ions, leaving 2 negatively charged electrons behind in the metal: anode: Zn → Zn2+ + 2 e−This reaction is called oxidation. While zinc is entering the electrolyte, two positively charged hydrogen ions from the electrolyte accept two electrons at the copper cathode surface, become reduced and form an uncharged hydrogen molecule: cathode: 2 H+ + 2 e− → H2This reaction is called reduction; the electrons used from the copper to form the molecules of hydrogen are made up by an external wire or circuit that connects it to the zinc.

The hydrogen molecules formed on the surface of the copper by t

Pablo Helman

Pablo Helman is an Argentine visual effects supervisor. He has received three Academy Award nominations for his work on the films Star Wars: Episode II – Attack of the Clones, War of the Worlds and The Irishman; the Irishman, 2019 The Mummy, 2017 Silence, 2016 Teenage Mutant Ninja Turtles: Out of the Shadows, 2016 Teenage Mutant Ninja Turtles, 2014 Pain & Gain, 2013 Battleship, 2012 Indiana Jones and the Kingdom of the Crystal Skull, 2008 The Spiderwick Chronicles, 2008 Munich, 2005 War of the Worlds, 2005 The Bourne Supremacy, 2004 The Chronicles of Riddick, 2004 Master and Commander: The Far Side of the World, 2003 Terminator 3: Rise of the Machines, 2003 Star Wars: Episode II – Attack of the Clones, 2002 The Pledge, 2001 2003: Nominated, 75th Academy Awards for Best Visual Effects, Star Wars: Episode II – Attack of the Clones with Rob Coleman, John Knoll and Ben Snow 2003: Won, 29th Saturn Awards for Special Special Effects, Star Wars: Episode II – Attack of the Clones with Rob Coleman, John Knoll and Ben Snow 2006: Nominated, 78th Academy Awards for Best Visual Effects, War of the Worlds with Randal M. Dutra, Dennis Muren and Daniel Sudick 2020: Nominated, 92nd Academy Awards for Best Visual Effects, The Irishman with Leandro Estebecorena, Nelson Sepulveda-Fauser, Stephane Grabil Pablo Helman on IMDb

Unfinished (film)

Unfinished is a 2018 South Korean drama thriller film directed by Noh Kyu-yeob. The film stars Yeon Woo-jin, Park Joo-mi and Lee Jong-hyuk; the film was released on November 14, 2018. It is based on the true story of Oh Kil-nam. Set in Berlin in 1986, the story revolves around Oh Young-Min, who has become a wanted man due to a run-in with a North Korean spy; the spy convinces him to move to North Korea under the pretext of safety for his family. As the story unfolds, he realizes that this was a bad decision and flees to West Germany where he is separated from his family. To make things worse, he is under surveillance by various countries, all wanting to exploit him for different purposes. Lee Beom-soo as Oh Young-min Yeon Woo-jin as Choi Moo-hyuk Park Joo-mi Lee Jong-hyuk as Choi Gi-chul Park Hyuk-kwon The film is based on the memoirs of Oh Kil-nam. Oh, a South Korean economist in Germany, moved to North Korea with his wife Shin Suk-ja and his two daughters, he returned to Europe but was accused of being a North Korean operative.

Following his surrender at the South Korean embassy in Germany in 1992, his wife and daughters were imprisoned in North Korea's Yodok concentration camp. The issue became a cause célèbre among South Korean conservatives. Choi Hong-jae, an official at the presidential Blue House during the early Park Geun-hye administration, was involved in the campaign to raise public awareness of Shin's imprisonment. Choi convinced SH Film, whose CEO was an alumnus of Choi's alma mater Korea University, to purchase the film rights to Oh's memoirs. Principal photography began in September 2016 and was completed in December 2016; the film was set to be released in April 2017, but was pushed to 14 November 2018 due to the whitelist scandal involving former South Korean President Park Geun-hye. In March 2017, it was revealed that the film's production team was suspected of being one of the pro-government organizations that received illegal funds. On 31 May 2017, two months after Park Geun-hye's whitelist was revealed, the film was accused of being funded by the government.

Kim Uh-jun from Kim Uh-jun's Newsroom reported that, of the total production cost of the film of ₩ 4.5 billion, about ₩ 4.3 billion was financed by the government. He mentioned that the film was intended to promote patriotism, to induce public support for the government. Unfinished at HanCinema Unfinished at Naver Unfinished at Eontalk