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Adolf Wüllner
Adolf Wüllner (13 June 1835, in Düsseldorf – 6 October 1908, in Aachen) was a German physicist. He studied physics at the universities of University of Bonn, Bonn, University of Munich, Munich and Berlin, qualifying as a lecturer at the University of Marburg in 1858. In 1862 he became director of the vocational school in Aachen, and three years later taught classes in physics at the Poppelsdorf agricultural academy. In 1867 he was named an associate professor at the University of Bonn, and from 1869 onward, was a professor of physics at the RWTH Aachen University, Technical University of Aachen. In 1883–86 he served as rector (academia), academic rector.MKL1888:Wüllner Meyers Konversations-Lexikon He is remembered for his work on the specific heat of liquids and gases, vapor pressure, vapor tension, refractive index, refr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emission Spectra
The emission spectrum of a chemical element or chemical compound is the spectrum of frequencies of electromagnetic radiation emitted due to electrons making a transition from a high energy state to a lower energy state. The photon energy of the emitted photons is equal to the energy difference between the two states. There are many possible electron transitions for each atom, and each transition has a specific energy difference. This collection of different transitions, leading to different radiated wavelengths, make up an emission spectrum. Each element's emission spectrum is unique. Therefore, spectroscopy can be used to identify elements in matter of unknown composition. Similarly, the emission spectra of molecules can be used in chemical analysis of substances. Emission In physics, emission is the process by which a higher energy quantum mechanical state of a particle becomes converted to a lower one through the emission of a photon, resulting in the production of light. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
19th-century German Physicists
The 19th century began on 1 January 1801 (represented by the Roman numerals MDCCCI), and ended on 31 December 1900 (MCM). It was the 9th century of the 2nd millennium. It was characterized by vast social upheaval. Slavery was abolished in much of Europe and the Americas. The First Industrial Revolution, though it began in the late 18th century, expanded beyond its British homeland for the first time during the 19th century, particularly remaking the economies and societies of the Low Countries, France, the Rhineland, Northern Italy, and the Northeastern United States. A few decades later, the Second Industrial Revolution led to ever more massive urbanization and much higher levels of productivity, profit, and prosperity, a pattern that continued into the 20th century. The Catholic Church, in response to the growing influence and power of modernism, secularism and materialism, formed the First Vatican Council in the late 19th century to deal with such problems and confirm ce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Academic Staff Of RWTH Aachen University
An academy (Attic Greek: Ἀκαδήμεια; Koine Greek Ἀκαδημία) is an institution of tertiary education. The name traces back to Plato's school of philosophy, founded approximately 386 BC at Akademia, a sanctuary of Athena, the goddess of wisdom and Skills, skill, north of Ancient Athens, Athens, Greece. The Royal Spanish Academy defines academy as scientific, literary or artistic society established with public authority and as a teaching establishment, public or private, of a professional, artistic, technical or simply practical nature. Etymology The word comes from the ''Academy'' in ancient Greece, which derives from the Athenian hero, ''Akademos''. Outside the city walls of Athens, the Gymnasium (ancient Greece), gymnasium was made famous by Plato as a center of learning. The sacred space, dedicated to the goddess of wisdom, Athena, had formerly been an olive Grove (nature), grove, hence the expression "the groves of Academe". In these gardens, the philos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scientists From Düsseldorf
A scientist is a person who Scientific method, researches to advance knowledge in an Branches of science, area of the natural sciences. In classical antiquity, there was no real ancient analog of a modern scientist. Instead, philosophers engaged in the philosophical study of nature called natural philosophy, a precursor of natural science. Though Thales ( 624–545 BC) was arguably the first scientist for describing how cosmic events may be seen as natural, not necessarily caused by gods,Frank N. Magill''The Ancient World: Dictionary of World Biography'', Volume 1 Routledge, 2003 it was not until the 19th century in science, 19th century that the term ''scientist'' came into regular use after it was coined by the theologian, philosopher, and historian of science William Whewell in 1833. History The roles of "scientists", and their predecessors before the emergence of modern scientific disciplines, have evolved considerably over time. Scientists of different er ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1908 Deaths
This is the longest year in either the Julian or Gregorian calendars, having a duration of 31622401.38 seconds of Terrestrial Time (or ephemeris time), measured according to the definition of mean solar time. Events January * January 1 – The British Nimrod Expedition, ''Nimrod'' Expedition led by Ernest Shackleton sets sail from New Zealand on the ''Nimrod (1867 ship), Nimrod'' for Antarctica. * January 3 – A Solar eclipse of January 3, 1908, total solar eclipse is visible in the Pacific Ocean and is the 46th solar eclipse of Solar Saros 130. * January 13 – A fire breaks out at the Rhoads Opera House fire, Rhoads Opera House in Boyertown, Pennsylvania, killing 171 people. * January 15 – Alpha Kappa Alpha, the first race inclusive sorority is founded on the campus of Howard University in Washington, D.C. * January 24 – Robert Baden-Powell's ''Scouting for Boys'' begins publication in London. The book eventually sells over 100 million copies, and effectively be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1835 Births
Events January–March * January 7 – anchors off the Chonos Archipelago on her second voyage, with Charles Darwin on board as naturalist. * January 8 – The United States public debt contracts to zero, for the only time in history. * January 24 – Malê Revolt: African slaves of Yoruba Muslim origin revolt against Brazilian owners at Salvador, Bahia. * January 26 ** Queen Maria II of Portugal marries Auguste de Beauharnais, 2nd Duke of Leuchtenberg, in Lisbon; he dies only two months later. ** Saint Paul's in Macau is largely destroyed by fire after a typhoon hits. * January 30 – The first assassination attempt against a President of the United States is carried out against U.S. President Andrew Jackson at the United States Capitol * February 1 – Slavery is abolished in Mauritius. * February 20 – 1835 Concepción earthquake: Concepción, Chile, is destroyed by an earthquake. The resulting tsunami destroys the neighboring city of Talcahuano. * March 2 – ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Annalen Der Physik Und Chemie
''Annalen der Physik'' (English: ''Annals of Physics'') is one of the oldest scientific journals on physics; it has been published since 1799. The journal publishes original, peer-reviewed papers on experimental, theoretical, applied, and mathematical physics and related areas. The editor-in-chief is Stefan Hildebrandt. Prior to 2008, its ISO 4 abbreviation was ''Ann. Phys. (Leipzig)'', after 2008 it became ''Ann. Phys. (Berl.)''. The journal is the successor to , published from 1790 until 1794, and ', published from 1795 until 1797. The journal has been published under a variety of names (', ', ', ''Wiedemann's Annalen der Physik und Chemie'') during its history. History Originally, was published in German, then a leading scientific language. From the 1950s to the 1980s, the journal published in both German and English. Initially, only foreign authors contributed articles in English but from the 1970s German-speaking authors increasingly wrote in English in order to reach an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dioptrics
Dioptrics is the branch of optics dealing with refraction, especially by lenses. In contrast, the branch dealing with mirrors is known as '' catoptrics''. Telescopes that create their image with an objective that is a convex lens ( refractors) are said to be "dioptric" telescopes. An early study of dioptrics was conducted by Ptolemy in relationship to the human eye as well as refraction in media such as water. The understanding of the principles of dioptrics was further expanded by Alhazen, considered the father of modern optics. See also * Diopter/Dioptre (unit of measurement) * Dioptrice (work by Johannes Kepler) * Catoptrics (study of and optical systems utilizing reflection) * Catadioptrics (study of and optical systems utilizing reflection and refraction) * Optical telescope An optical telescope gathers and focus (optics), focuses light mainly from the visible spectrum, visible part of the electromagnetic spectrum, to create a magnification, magnified image for di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isotropy
In physics and geometry, isotropy () is uniformity in all orientations. Precise definitions depend on the subject area. Exceptions, or inequalities, are frequently indicated by the prefix ' or ', hence ''anisotropy''. ''Anisotropy'' is also used to describe situations where properties vary systematically, dependent on direction. Isotropic radiation has the same intensity regardless of the direction of measurement, and an isotropic field exerts the same action regardless of how the test particle is oriented. Mathematics Within mathematics, ''isotropy'' has a few different meanings: ; Isotropic manifolds: A manifold is isotropic if the geometry on the manifold is the same regardless of direction. A similar concept is homogeneity. ; Isotropic quadratic form: A quadratic form ''q'' is said to be isotropic if there is a non-zero vector ''v'' such that ; such a ''v'' is an isotropic vector or null vector. In complex geometry, a line through the origin in the direction of an is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Experimental Physics
Experimental physics is the category of disciplines and sub-disciplines in the field of physics that are concerned with the observation of physical phenomena and experiments. Methods vary from discipline to discipline, from simple experiments and observations, such as experiments by Galileo Galilei, to more complicated ones, such as the Large Hadron Collider. Overview Experimental physics is a branch of physics that is concerned with data acquisition, data-acquisition methods, and the detailed conceptualization (beyond simple thought experiments) and realization of laboratory experiments. It is often contrasted with theoretical physics, which is more concerned with predicting and explaining the physical behaviour of nature than with acquiring empirical data. Although experimental and theoretical physics are concerned with different aspects of nature, they both share the same goal of understanding it and have a symbiotic relationship. The former provides data about the universe, wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
