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Antonio Stradivari

Antonio Stradivari was an Italian luthier and a crafter of string instruments such as violins, guitars and harps. The Latinized form of his surname, Stradivarius, as well as the colloquial Strad are terms used to refer to his instruments, it is estimated. Around 650 instruments survived, including 450 to 512 violins. Antonio Stradivari's birthdate between 1644 and 1649, has been debated amongst historians due to the numerous inconsistencies in the evidence of the latter; the 1668 and 1678 censuses report him growing younger, a fact explained by the probable loss of statistics from 1647–49, when renewed belligerency between France's Modenese and Spain's Milanese proxies led to a flow of refugees that included Stradivari's mother. Stradivari's ancestry consisted of notable citizens of Cremona, dating back to at least the 12th or 13th century; the earliest mention of the family name, or a variation upon it, is in a land grant dating from 1188. The origin of the name itself has several possible explanations.

Antonio's parents were Alessandro Stradivari, son of Giulio Cesare Stradivari, Anna Moroni, daughter of Leonardo Moroni. They married on 30 August 1622, had at least three children between 1623 and 1628: Giuseppe Giulia Cesare, Carlo Felice, Giovanni Battista; the baptismal records of the parish of S. Prospero stop, it is unknown whether they had any children from 1628 to 1644; this gap in the records may be due to the family leaving Cremona in response to war and plague in the city from 1628 to 1630, or the records may have been lost due to clerical reforms imposed by Joseph II of Austria in 1788. The latter explanation is supported by the word Cremonensis on many of Stradivari's labels, which suggests that he was born in the city instead of moving back there to work. Antonio was born in 1644, a fact deducible from violins. However, there are no records or information available on his early childhood, the first evidence of his presence in Cremona is the label of his oldest surviving violin from 1666.

Stradivari began an apprenticeship with Nicola Amati between the ages of 12 and 14, although a minor debate surrounds this fact. One of the few pieces of evidence supporting this is the label of his 1666 violin, which reads, Alumnus Nicolai Amati, faciebat anno 1666. However, Stradivari did not put Amati's name on his labels, unlike many of Amati's other students. Stradivari's early violins bear less resemblance to Amati's than his instruments do. M. Chanot-Chardon, a well-known French luthier, asserted that his father had a label of Stradivari's stating, "Made at the age of thirteen, in the workshop of Nicolò Amati"; this label has never been confirmed. Amati would have been a logical choice for Antonio's parents, as he represented an old family of violin makers in Cremona, was far superior to most other luthiers in Italy; some researchers believe there is a closer educational association between Antonio Stradivari and Francesco Rugeri than has been recognized. Despite the long-held belief that Antonio Stradivari was the pupil of Nicolò Amati, there are important discrepancies between their work.

Some researchers believe early instruments by Stradivari bear a stronger resemblance to Francesco Rugeri's work than Amati's. Additionally, the utilization of a small dorsal pin or small hole, invariably used not just by Nicolò Amati but all of his recognized pupils—with the exception of Antonio Stradivari, adds further evidence that Stradivari may have learnt his craft apart from Amati; this pin or hole was fundamental in the graduation of the thickness of the plates and was a technique passed on through generations of pupils of the Amati. This dorsal pin is not found in any of the instruments of the Rugeri family, suggesting Antonio Stradivari may have learnt his craft from Francesco Rugeri, although both being influenced by Amati. W. E. Hill & Sons concede that they fail to find the hand of Stradivari in any of Nicolo Amati's work, although the unmistakable hands of Andrea Guarneri and Francesco Rugeri are evident. An alternative theory is that Stradivari started out as a woodworker: the house he lived in from 1667 to 1680 was owned by Francesco Pescaroli, a woodcarver and inlayer.

Stradivari may have been employed to decorate some of Amati's instruments, without being a true apprentice. This theory is supported by some of Stradivari's violins, which have elaborate decorations and purfling. Assuming that Stradivari was a student of Amati, he would have begun his apprenticeship in 1656–58 and produced his first decent instruments in 1660, at the age of 16, his first labels were printed from 1660 to 1665, which indicates that his work had sufficient quality to be offered directly to his patrons. However, he stayed in Amati's workshop until about 1684, using his master's reputation as a launching point for his career. Stradivari married his first wife, Francesca Ferraboschi, on 4 July 1667. Francesca was the young widow of the burgher Giacomo Capra, with. Francesca's brother had shot Giacomo with a crossbow on the Piazza Garibaldi in 1664, he was exiled, though allowed to return to Cremona many years later. After their marriage, Stradivari moved into a house known as the Casa del Pescatore, or the Casa Nuziale, in his wife's parish.

A clue to how they would have met lies in the 1659

Nuclear reactor coolant

A nuclear reactor coolant is a coolant in a nuclear reactor used to remove heat from the nuclear reactor core and transfer it to electrical generators and the environment. A chain of two coolant loops are used because the primary coolant loop takes on short-term radioactivity from the reactor. All operating nuclear power plants are light water reactors using ordinary water under high pressure as coolant and neutron moderator. About 1/3 are boiling water reactors where the primary coolant undergoes phase transition to steam inside the reactor. About 2/3 are pressurized water reactors at higher pressure. Current reactors stay under the critical point at around 374 °C and 218 bar where the distinction between liquid and gas disappears, which limits thermal efficiency, but the proposed supercritical water reactor would operate above this point. Heavy water reactors use deuterium oxide which has identical properties to ordinary water but much lower neutron capture, allowing more thorough moderation.

As the hydrogen atoms in water coolants are bombarded with neutrons, some absorb a neutron to become deuterium, some become radioactive tritium. Water contaminated with tritium sometimes leaks to groundwater by accident or by official approval The fuel rods create high temperatures which boil water turn water to steam. During a disaster, when a power outage happens and diesel power generators which provide emergency power to the water pump are damaged by a tsunami or an earthquake, if no fresh water is being pumped to cool the fuel rods the fuel rods continue to heat up. Once the fuel rods reach more than 1200 degrees Celsius, the zirconium tubes that contain the nuclear fuel will interact with the steam and split the hydrogen from the water; that hydrogen can be released from the reactor core and containment vessel. If that hydrogen accumulates in sufficient quantities-concentrations of 4 percent or more in the air that hydrogen can explode, as has occurred at Fukushima Daiichi reactors No.

1, 3, 4 but reactor No. 2 opened its vent to let out radioactive hydrogen gas, decreasing the pressure of the hydrogen, but it contaminated the environment, so reactor No. 2 did not explode Borated water is used as a coolant during normal operation of pressurized water reactors as well as in Emergency Core Cooling Systems of both PWRs and boiling water reactors. Boron in the form of boric acid or sodium borate, is combined with water — a cheap and plentiful resource — where it acts as a coolant to remove heat from the reactor core and transfers the heat to a secondary circuit. Part of the secondary circuit is the steam generator, used to turn turbines and generate electricity. Borated water provides the additional benefits of acting as a neutron poison due to its large neutron absorption cross-section, where it absorbs excess neutrons to help control the fission rate of the reactor. Thus, the reactivity of the nuclear reactor can be adjusted by changing the boron concentration in the coolant.

That is, when the boron concentration is increased by dissolving more boric acid into the coolant, the reactivity of the reactor is decreased. Conversely, when the boron concentration is decreased by adding more water, the reactivity of the reactor is increased. 90% of the tritium in PWR coolants is produced by reactions of boron-10 with neutrons. Since tritium itself is a radioactive isotope of hydrogen, the coolant becomes contaminated with radioactive isotopes and must be kept from leaking into the environment. Additionally, this effect must be taken into account for longer cycles of nuclear reactor operation and thus requires higher initial concentration of boron in the coolant. Fast reactors have a high power density and do not need, must avoid, neutron moderation. Most have been liquid metal cooled reactors using molten sodium. Lead, lead-bismuth eutectic, other metals have been proposed and used. Mercury was used in the first fast reactor. Molten salts share with metals the advantage of low vapor pressure at high temperatures, are less chemically reactive than sodium.

Salts containing light elements like FLiBe can provide moderation. In the Molten-Salt Reactor Experiment it served as a solvent carrying the nuclear fuel. Gases have been used as coolant. Helium is inert both chemically and with respect to nuclear reactions but has a low heat capacity, Organically moderated and cooled reactors were an early concept studied, using hydrocarbons as coolant, they were not successful. Sodium as a Fast Reactor Coolant, Thomas Fanning, ANL Compares sodium favorably to helium. Media related to Nuclear reactor coolants at Wikimedia Commons

Roque JĂșnior

José Vítor Roque Jr. more known as Roque Júnior, is a former association footballer who played as a defender. He last played for Ituano Futebol Clube, he was part of the winning squad at the 2002 World Cup. During his career, Roque Júnior has played for Santarritense, São José, Palmeiras, AC Milan, Leeds United, Bayer Leverkusen, MSV Duisburg and Qatari side Al-Rayyan, he is an iconic footballer for Palmeiras. His greatest success in club football came with playing for Palmeiras, with whom he won the 1999 Copa Libertadores. There was excitement at Elland Road when Peter Reid brought Roque to Leeds on loan, but it was short lived as the team conceded 24 times in his seven appearances and Roque was sent off on his home debut against Birmingham City. However, he did score two goals in a Worthington Cup game against Manchester United but his spell at Leeds was not considered a success. In September 2008, Palmeiras have signed him from Al-Rayyan on loan until the end of the season. After leaving Palmeiras in November 2008, he was offered to Australian A-League clubs in April and was in talks with Avaí gaffer Paulo Silas in July, but nothing materialised out of it.

In February 2010, Ituano FC signed the former Brazil international, who had last played in 2008 for Palmeiras. Roque Júnior was successful on the international stage for Brazil, having played 48 games and scored two goals, captaining them on a number of occasions, he was a starter in the 2002 FIFA World Cup winning campaign, forming the back line with Lúcio and Edmílson. He was called up for the 2005 FIFA Confederations Cup, but did not make it into the squad for the 2006 FIFA World Cup due to injury, he made his last international appearance in 2005 and announced his retirement on 4 September 2007. Roque Júnior is devoted to helping São José Esporte Clube's youth players with a project called "Projeto Primeira Camisa". Roque "Rogue" Junior was the most popular host of Total Request Live on Brazil MTV during his 10-year stint. In 2015, Roque Júnior took his first managerial role at XV de Piracicaba. Scores and results list Brazil's goal tally first PalmeirasCampeonato Paulista: 1996, 2008 Copa do Brasil: 1998 Copa Mercosur: 1998 Copa Libertadores: 1999 Torneio Rio – São Paulo: 2000MilanUEFA Champions League: 2002–03 Coppa Italia: 2002–03 BrazilFIFA World Cup: 2002 FIFA Confederations Cup: 2005 Roque Júnior at Sambafoot Roque Júnior at fussballdaten.de Who's who - Roque Junior Leverkusen.com