A catalytic converter is an exhaust emission control device that reduces toxic gases and pollutants in exhaust gas from an internal combustion engine into less-toxic pollutants by catalyzing a redox reaction. Catalytic converters are used with internal combustion engines fueled by either gasoline or diesel—including lean-burn engines as well as kerosene heaters and stoves; the first widespread introduction of catalytic converters was in the United States automobile market. To comply with the U. S. Environmental Protection Agency's stricter regulation of exhaust emissions, most gasoline-powered vehicles starting with the 1975 model year must be equipped with catalytic converters; these "two-way" converters combine oxygen with carbon monoxide and unburned hydrocarbons to produce carbon dioxide and water. In 1981, two-way catalytic converters were rendered obsolete by "three-way" converters that reduce oxides of nitrogen; this is because three-way-converters require either rich or stoichiometric combustion to reduce NO x.
Although catalytic converters are most applied to exhaust systems in automobiles, they are used on electrical generators, mining equipment, buses and motorcycles. They are used on some wood stoves to control emissions; this is in response to government regulation, either through direct environmental regulation or through health and safety regulations. Catalytic converter prototypes were first designed in France at the end of the 19th century, when only a few thousand "oil cars" were on the roads. A few decades a catalytic converter was patented by Eugene Houdry, a French mechanical engineer and expert in catalytic oil refining, who moved to the United States in 1930; when the results of early studies of smog in Los Angeles were published, Houdry became concerned about the role of smokestack exhaust and automobile exhaust in air pollution and founded a company called Oxy-Catalyst. Houdry first developed catalytic converters for smokestacks called "cats" for short, developed catalytic converters for warehouse forklifts that used low grade, unleaded gasoline.
In the mid-1950s, he began research to develop catalytic converters for gasoline engines used on cars. He was awarded United States Patent 2,742,437 for his work. Widespread adoption of catalytic converters did not occur until more stringent emission control regulations forced the removal of the antiknock agent tetraethyl lead from most types of gasoline. Lead is a catalyst poison and would disable a catalytic converter by forming a coating on the catalyst's surface. Catalytic converters were further developed by a series of engineers including Carl D. Keith, John J. Mooney, Antonio Eleazar, Phillip Messina at Engelhard Corporation, creating the first production catalytic converter in 1973. William C. Pfefferle developed a catalytic combustor for gas turbines in the early 1970s, allowing combustion without significant formation of nitrogen oxides and carbon monoxide; the catalytic converter's construction is as follows: The catalyst substrate. For automotive catalytic converters, the core is a ceramic monolith that has a honeycomb structure.
Metallic foil monoliths made of Kanthal are used in applications where high heat resistance is required. The substrate is structured to produce a large surface area; the cordierite ceramic substrate used in most catalytic converters was invented by Rodney Bagley, Irwin Lachman, Ronald Lewis at Corning Glass, for which they were inducted into the National Inventors Hall of Fame in 2002. The washcoat. A washcoat is a carrier for the catalytic materials and is used to disperse the materials over a large surface area. Aluminum oxide, titanium dioxide, silicon dioxide, or a mixture of silica and alumina can be used; the catalytic materials are suspended in the washcoat prior to applying to the core. Washcoat materials are selected to form a rough, irregular surface, which increases the surface area compared to the smooth surface of the bare substrate; this in turn maximizes the catalytically active surface available to react with the engine exhaust. The coat must retain its surface area and prevent sintering of the catalytic metal particles at high temperatures.
Ceria or ceria-zirconia. These oxides are added as oxygen storage promoters; the catalyst itself is most a mix of precious metals. Platinum is the most active catalyst and is used, but is not suitable for all applications because of unwanted additional reactions and high cost. Palladium and rhodium are two other precious metals used. Rhodium is used as a reduction catalyst, palladium is used as an oxidation catalyst, platinum is used both for reduction and oxidation. Cerium, iron and nickel are used, although each has limitations. Nickel is not legal for use in the European Union because of its reaction with carbon monoxide into toxic nickel tetracarbonyl. Copper can be used everywhere except Japan. Upon failure, a catalytic converter can be recycled into scrap; the precious metals inside the converter, including platinum and rhodium, are extracted. Catalytic converters require a temperature of 800 degrees Fahrenheit to efficiently convert harmful exhaust gases into inert gases, such as carbon dioxide and water vapor.
Therefore, the first catalytic converters were placed cl
Robert Fico's Third Cabinet was government of Slovakia, headed by prime minister Robert Fico. It replaced Fico's Second Cabinet on 23 March 2016 following the 2016 parliamentary election, in which Fico's Direction – Social Democracy party lost its parliamentary majority, met for the first time on March 30, it consists of 15 members including the prime minister, was composed of four parties: Smer–SD, the Slovak National Party, the Slovak-Hungarian Most–Híd party, the Network party. Most of the elected MPs of Network party joined Most-Híd shortly after the elections and the party is dissolved. On 15 March 2018, in the wake of the political crisis following the murder of Ján Kuciak, Fico delivered his resignation to President Andrej Kiska. New cabinet led by Peter Pellegrini was appointed on 22 March 2018. After the dissolution of the government on the 22 March 2018, most of the ministers stayed on their positions, continued in the new cabinet of Pellegrini. Notes Smer–SD nominee Slovak National Party nominee Fico's First Cabinet
The Shahnameh of Shah Tahmasp or Houghton Shahnameh is one of the most famous illustrated manuscripts of the Shahnameh, the national epic of Greater Iran, a high point in the art of the Persian miniature. It is the most illustrated manuscript of the text produced; when created, the manuscript contained 759 pages. These miniatures were hand painted by the artists of the royal workshop in Tabriz under rulers Shah Ismail I and Shah Tahmasp I. Upon its completion, the Shahnameh was gifted to Ottoman Sultan Selim II in 1568; the page size is about 48 x 32 cm, the text written in Nastaʿlīq script of the highest quality. The manuscript was broken up in the 1970s and pages are now in a number of different collections around the world, it was created in Tabriz at the order of Shah Ismail I who had taken control of the city. Shah Ismail I was a charismatic and militarily aggressive leader, which allowed him to conquer large swaths of territory with cosmopolitan populations; because of this, he had access to a wide variety of artists with many specialties and training in different styles, which allowed for the collaboration of artists and resulted in a new style of illumination named the Tabriz Style.
He commissioned the most prominent artists of Safavid Persia, to illustrate this manuscript as a demonstration of the shift in political landscape and as an assertion of his dominance as the Shah. A commission of the Shahnameh was a common way to assert legitimacy as a ruler because the text portrays the shah as a strong, stable individual, to be unquestionably obeyed and respected; such an expensive and lavishly decorated manuscript would have presented Ismail I as a successful and powerful leader tied to the strength and notoriety of the Persians. Most the manuscript was either intended to be given as a gift to Suleiman the Magnificent, sultan of the Ottoman Empire, or to celebrate the return of his son Tahmasp from a period as governor of Herat; the Shahnameh has been described as a history of the Iranian people. This makes it comparable to works with similar themes from other regions of the world, such as the Old Testament's Book of Kings or the Iliad. Although the exact dates are still debated, most scholars believe.
It would have taken multiple generations of artists to complete, many great artists took the position of director, including Sultan Mohammad, Mir Musavvir, Aqa Mirak. Shah Ismail I died in 1524 shortly after the work on the manuscript had begun. Tahmasp I succeeded the throne, but at 11 years old was not old enough to recognize the importance of promoting great art and culture in society, his advisers pushed for completion of the manuscript and it was close to completion by the mid-1530s during his reign. The Shahnameh was given to the Ottoman Sultan, Selim II, in 1568. Ottoman sources reveal that it arrived at the Iranian Embassy in February 1568, accompanied by 34 camels and other lavish gifts intended for the sultan. Both the sultan and his palace members were impressed with the manuscript, estimated to be 30,000 couplets long when it was first presented, it long remained in the Topkapı Palace library in Istanbul, commentaries added in the margins around 1800 prove that the remarkably decorated manuscript fascinated many rulers and scholars long after its completion.
When the Ottoman empire fell apart in the early 1900s, the manuscript appeared in the collection of Edmond James de Rothschild. It stayed in the Rothschild family and was acquired by Arthur Houghton II; the manuscript once were sold individually by Houghton to avoid taxes. Houghton kept 118 miniatures for himself, donated 78 paintings to the Metropolitan Museum of Art in 1972 and sold the rest to other and publicly owned collections around the world. Following the 1979 Islamic Revolution in Iran, efforts were made to reclaim miniatures from this manuscript but never succeeded; the Metropolitan's miniatures have been the subject of a 15 million dollar exchange agreement with the National Museum of Iran. The dispersed miniatures are in several collections, including the Khalil Collections, which holds 10 folios. On 6 April 2011, a page from this manuscript from the collection of the leading scholar of the manuscript, Stuart Cary Welch, was sold for 7.4 million pounds. The huge scale of the work, which consisted of 759 pages total including 258 miniatures, would have required help from all the leading artists of the royal workshop.
Some of the artists identified are Mir Sayyid Ali, Sultan Mohammad, Mizra-Ali Aqa Mirak, Mir Musavvir, Dust Muhammad, Abd al-Samad. A number of artists are not known by name; each page size is about 48 x 32 cm with text written in quality Nastaʿlīq script. The style of the miniatures varies though the quality is high. Although many of the miniatures have mythical motifs, they depict everyday objects that would have been common in the Safavid period in Iran; this makes the miniatures unique to place. The manuscript shows the fusion of the styles of the schools of Herat, where the Timurid royal workshops had developed a style of classical restraint and elegance, the painters of Tabriz, whose style was more expressive and imaginative. Tabriz was the former capital of the Turkmen rulers, successively of the Kara Koyunlu and Ağ Qoyunlu, who had ruled much of Persia before Ismail I defeated them and began the Safavid dynasty in 1501. Dust Muhammad wrote an account of Persian painting, it is the first of many acc