Physical coefficient
A physical coefficient is an important number that characterizes some physical property of a technical or scientific object.
Coefficient of thermal expansion
Solids mostly expand in response to heating and contract on cooling. This response to temperature change is expressed as its coefficient of thermal expansion.
The coefficient of thermal expansion is used:
These characteristics are closely related. The volumetric thermal expansion coefficient can be measured for all substances of condensed matter (liquids and solid state). The linear thermal expansion can only be measured in the solid state and is common in engineering applications.
The expansion and contraction of material must be considered when designing large structures, when using tape or chain to measure distances for land surveys, when designing molds for casting hot material, and in other engineering applications when large changes in dimension due to temperature are expected. The range for α is from 10 for hard solids to 10 for organic liquids. α varies with the temperature and some materials have a very high variation. Some values for common materials, given in parts per million per Celsius degree: (NOTE: This can also be in kelvins as the changes in temperature are a 1:1 ratio)
For applications using the thermal expansion property, see bi-metal and mercury thermometer
Thermal expansion is also used in mechanical applications to fit parts over one another, e.g. a bushing can be fitted over a shaft by making its inner diameter slightly smaller than the diameter of the shaft, then heating it until it fits over the shaft, and allowing it to cool after it has been pushed over the shaft, thus achieving a 'shrink fit'
There exist some alloys with a very small CTE, used in applications that demand very small changes in physical dimension over a range of temperatures. One of these is Invar 36, with a coefficient in the 0.6x10 range. These alloys are useful in aerospace applications where wide temperature swings may occur.
Surveying
Surveying is the technique and science of accurately finding out the position of points and the distances and angles between them. These points are usually, but not always, associated with positions on the surface of the Earth. They are often used to make land maps and boundaries for ownership of land. A person who does the surveying is called a surveyor. In order to find the information they need, surveyors use geometry, engineering, trigonometry, mathematics, physics, and law.
Surveying has been very important in the development of the human environment since the beginning of recorded history (ca. 5000 years ago) and it is a requirement planning of nearly every form of construction. Its most common uses are in the fields of transport, building and construction, communications, mapping, and the making of legal boundaries for land ownership.
Surveying has existed throughout much of our history. In ancient Egypt, when the Nile River overflowed its banks and washed out farm boundaries, the boundaries were recreated by surveyors using simple geometry. The construction of many of the pyramids, including the Great Pyramids of Giza, built c. 2700 BC, show us that the Egyptians' have always used surveying very efficiently.
A surveyor is a person who has the skills to accurately find out the position of points and the distances and angles between them. These points are usually, positions on the surface of the Earth. Finding these points is called "surveying". Surveyors are needed to make land maps and boundaries for ownership of land. In order to find the information they need, surveyors use geometry, engineering, trigonometry, mathematics, physics, and law.
There are different types of surveyor. A construction or building surveyor is the person who has to make sure that buildings are being put up in the correct place and fit in with planning and building laws. A quantity surveyor is the person who keeps track of costs on a building project. A hydrographic surveyor measures points to do with water, such as rivers, lakes and oceans. A marine surveyor is a person who inspects ships. A mine surveyor is the person who finds out the position of underground mines, for example gold mines or coal mines.
Jorge Manrique
Jorge Manrique (c. 1440 – 1479) was a major Spanish poet, whose main work, the "Coplas a la muerte de su padre (Stanzas about the Death of his Father)", is still read today. He was a supporter of the great Spanish queen, Isabel I of Castile, and actively participated on her side in the civil war that broke out against her half-brother, Enrique IV, when the latter attempted to make his daughter, Juana, crown princess. Jorge died in 1479 during an attempt to take the castle of Garcimuñoz after Isabel gained the crown.
Manrique were one of major Spanish aristocratic families of the Jewish converso descent. See, Norman Roth, "Conversos, Inquisition, and the Expulsion of the Jews from Spain", Madison, WI: The University of Wisconcin Press, 1995, p. 333. Jorge Manrique was a great-nephew of Iñigo López de Mendoza (marquess of Santillana), a descendant of Pero López de Ayala, chancellor of Castile, and a nephew of Gómez Manrique, "corregidor" of Toledo, all important poets of the late fourteenth and fifteenth centuries. He was, therefore, a member of a noble family of great consequence.
Minutes to Midnight
Minutes to Midnight is third studio album by American nu metal band, Linkin Park. Production on the album started as early as late 2003, and initially had a projected release date of sometime in late 2004 or early 2005, but was scrapped due to touring and support of their previous album, Meteora, then prouduction started back up in 2006. It was released on May 14, 2007 all over the world and on May 15, 2007 in North America. Rick Rubin and Mike Shinoda produced the album.
The name "Minutes to Midnight" comes from the Doomsday Clock.
Thelxinoe (moon)
Thelxinoe or ' is a moon of Jupiter. It was found by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2004 from pictures taken in 2003, and originally got the designation '.
Thelxinoe is about 2 kilometres in diameter, and orbits Jupiter at an average distance of 20,454,000 km in 597.607 days, at an inclination of 151° to the ecliptic (153° to Jupiter's equator), with an orbital eccentricity of 0.2685.
It was named in March 2005 after Thelxinoe, one of the four original Muses according to some Greek writers, and a daughter of Zeus (Jupiter) by Mnemosyne.
Thelxinoe belongs to the Ananke group, retrograde non-spherical moons which orbit Jupiter between 19,300,000 and 22,700,000 km, at inclinations of about 150°.
Oskar Lafontaine
Oskar Lafontaine (; born 16 September 1943 in Saarlouis-Roden) is a left-wing German politician and a founder member of the new political party "Die Linke".
Lafontaine studied physics at the Bonn University and the Saarland University from 1962 to 1969.
He is Roman Catholic and is married to Christa Müller who leads a campaign against genital mutilation in Africa. They have a son, Carl Maurice, born 1997.
Lafontaine's political career began locally as mayor of Saarbrücken. He became widely known as a critic of chancellor Helmut Schmidt's support for the NATO plan to put Pershing II missiles in Germany. From 1985 to 1998 he was Minister-President of the Saarland. As minister-president, Lafontaine tried to keep the traditional industries of steel production and coal mining in the state with subsidies. He was also President of the Bundesrat in 1992/93.
In the German federal election of 1990, Lafonntaine was the SPD's Chancellor candidate. The party lost because of support for the CDU who were the government during reunification. During the campaign he was attacked with a knife by a mentally deranged woman after a speech in Cologne. His carotid artery was slashed and he remained in a critical condition for several days.