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SUMMARY / RELATED TOPICS

Fourier-transform spectroscopy

Fourier-transform spectroscopy is a measurement technique whereby spectra are collected based on measurements of the coherence of a radiative source, using time-domain or space-domain measurements of the electromagnetic radiation or other type of radiation. It can be applied to a variety of types of spectroscopy including optical spectroscopy, infrared spectroscopy, nuclear magnetic resonance and magnetic resonance spectroscopic imaging, mass spectrometry and electron spin resonance spectroscopy. There are several methods for measuring the temporal coherence of the light, including the continuous wave Michelson or Fourier-transform spectrometer and the pulsed Fourier-transform spectrograph; the term Fourier-transform spectroscopy reflects the fact that in all these techniques, a Fourier transform is required to turn the raw data into the actual spectrum, in many of the cases in optics involving interferometers, is based on the Wiener–Khinchin theorem. One of the most basic tasks in spectroscopy is to characterize the spectrum of a light source: how much light is emitted at each different wavelength.

The most straightforward way to measure a spectrum is to pass the light through a monochromator, an instrument that blocks all of the light except the light at a certain wavelength. The intensity of this remaining light is measured; the measured intensity directly indicates. By varying the monochromator's wavelength setting, the full spectrum can be measured; this simple scheme in fact describes. Fourier-transform spectroscopy is a less intuitive way to get the same information. Rather than allowing only one wavelength at a time to pass through to the detector, this technique lets through a beam containing many different wavelengths of light at once, measures the total beam intensity. Next, the beam is modified to contain a different combination of wavelengths, giving a second data point; this process is repeated many times. Afterwards, a computer takes all this data and works backwards to infer how much light there is at each wavelength. To be more specific, between the light source and the detector, there is a certain configuration of mirrors that allows some wavelengths to pass through but blocks others.

The beam is modified for each new data point by moving one of the mirrors. As mentioned, computer processing is required to turn the raw data into the desired result; the processing required turns out to be a common algorithm called the Fourier transform. The raw data is sometimes called an "interferogram"; because of the existing computer equipment requirements, the ability of light to analyze small amounts of substance, it is beneficial to automate many aspects of the sample preparation. The sample can be better preserved and the results are much easier to replicate. Both of these benefits are important, for instance, in testing situations that may involve legal action, such as those involving drug specimens; the method of Fourier-transform spectroscopy can be used for absorption spectroscopy. The primary example is a common technique in chemistry. In general, the goal of absorption spectroscopy is to measure how well a sample absorbs or transmits light at each different wavelength. Although absorption spectroscopy and emission spectroscopy are different in principle, they are related in practice.

First, the emission spectrum of a broadband lamp is measured. Second, the emission spectrum of the same lamp shining through the sample is measured; the sample will absorb some of the light. The ratio of the "sample spectrum" to the "background spectrum" is directly related to the sample's absorption spectrum. Accordingly, the technique of "Fourier-transform spectroscopy" can be used both for measuring emission spectra, absorption spectra; the Michelson spectrograph is similar to the instrument used in the Michelson–Morley experiment. Light from the source is split into two beams by a half-silvered mirror, one is reflected off a fixed mirror and one off a movable mirror, which introduces a time delay—the Fourier-transform spectrometer is just a Michelson interferometer with a movable mirror; the beams interfere, allowing the temporal coherence of the light to be measured at each different time delay setting converting the time domain into a spatial coordinate. By making measurements of the signal at many discrete positions of the movable mirror, the spectrum can be reconstructed using a Fourier transform of the temporal coherence of the light.

Michelson spectrographs are capable of high spectral resolution observations of bright sources. The Michelson or Fourier-transform spectrograph was popular for infra-red applications at a time when infra-red astronomy only had single-pixel detectors. Imaging Michelson spectrometers are a possibility, but in general have been supplanted by imaging Fabry–Pérot instruments, which are easier to construct; the intensity as a function of the path length difference (also denoted as retarda

Carl Johann Lasch

Carl Johann Lasch was a German artist of historical paintings. He was born in Leipzig, he attended the Dresden Academy of Fine Arts. One of his teachers was Eduard Bendemann, he attended the Academy of Fine Arts, Munich. There he studied under Wilhelm von Kaulbach. Apothéose de Henri IV, 1858, Kopie nach Peter Paul Rubens Portrait de jeune Femme, Verbleib unbekannt Le Tannhaeuser, Verbleib unbekannt Tintoretto und seine Tochter, Verbleib unbekannt. Kinderlust Bei der jungen Witwe Heimkehr von der Kirchweih Der Dorfarzt in Verlegenheit Hinter der Mühle Des alten Schullehrers Geburtstag Die Verhaftung. Ein Lexikon zur Ausbildung deutscher Maler in der französischen Hauptstadt. Band 2: 1844–1870. Berlin/Boston 2015

Dunmurry railway station

Dunmurry railway station is located in the townland of Dunmurry in west Belfast, County Antrim, Northern Ireland. The Ulster Railway station opened on 12 August 1839, it lies between the centres of Belfast and Lisburn, thus making it a busy commuter station during peak hours. Mondays to Saturdays there is a half hourly service towards Lisburn, Portadown or Newry in one direction, to Great Victoria Street, Belfast Central or Bangor in the other. Extra services operate at peak times, the service reduces to hourly operation in the evenings. On Sundays there is an hourly service in each direction. Dunmurry station is a fifteen-minute train journey away from Lisburn, or a twenty-minute journey from Belfast Central, where intending passengers can board the Enterprise service to Dublin Connolly. Media related to Dunmurry railway station at Wikimedia Commons

Ray Jackson (Aboriginal activist)

Ray Jackson was an Australian Aboriginal activist and Wiradjuri elder. He was President of the Indigenous Social Justice Association, a prominent campaigner for the rights of Indigenous Australians. Ray Jackson was a member of the Stolen Generations. In 1943, when Jackson was two years old, his father was killed in World War II, fighting Japanese forces on the Kokoda Track. Jackson said that instead of his biological mother receiving a war widows pension, the Australian government removed her four children from her custody due to her Aboriginality, his name was changed and he was sent to a Catholic institution for a year, before being adopted by a white family. It was not until his teen years, he never found his biological family, never learned the original name they had given him. Jackson was one of Australia's most prominent and knowledgeable campaigners on the issue of Aboriginal deaths in custody, he campaigned for justice for the families of Eddie Murray, Mark Mason and TJ Hickey. Between 1991 and 1997, Jackson was coordinator of the Aboriginal Deaths In Custody Watch Committee, financed by the government agency, ATSIC.

In an interview published by Green Left Weekly, Jackson said: "We were so well set we had a hotline any blackfella could call, anytime. If a copper so much as verballed a black kid, we'd get a call and be out at the police station, no matter where it was — at the latest — a day interrogating them." However, when the government led by Prime Minister John Howard cut all funding to the committee, Jackson established the Indigenous Social Justice Association to continue the work. Jackson's small Waterloo apartment was full of shelves and folders containing meticulous records about Aboriginal deaths in custody, he would attend the scenes where people had died at the hands of police, represent the deceased's families when dealing with the police and authorities. In December 2013, the French government agency Commission nationale consultative des droits de l'homme awarded Jackson's Indigenous Social Justice Association a prize of 70,000 euros in recognition of its contribution to human rights. Jackson was responsible for hundreds of rallies and actions in remembrance of lost lives to injustices.

Jackson confronted police annually in enabling the TJ Hickey January marches from Redfern where he died to NSW Parliament in the heart of the City of the Sydney. Jackson was a speaker at protest rallies for Aboriginal rights. Affectionately known as Uncle Ray, he would always attend the rallies wearing in his trademark black cap, decorated with social justice pins, he was a prominent supporter of the Redfern Aboriginal Tent Embassy, was a familiar sight there up until his death. In the months before his death, Ray Jackson had not been feeling well, a week before his death he was hospitalised with pneumonia. Shortly after attending a meeting of the Indigenous Social Justice Association, he died peacefully in his sleep on 23 April 2015, his granddaughter found him in bed that day in his Waterloo flat. At Jackson's request, his body was donated to the University of Sydney

Reyes Tamez

Reyes Tamez Guerra is a Mexican immunochemist. He is a former Secretary of Education for the State of Nuevo León, a former president of the Autonomous University of Nuevo León and a former Secretary of Education in the cabinet of Vicente Fox. Tamez Guerra graduated from the Autonomous University of Nuevo León in 1975 with a bachelor's degree in Chemistry and Parasitology and received both a master's degree and a doctorate's degree in immunology at the National Polytechnic Institute. On he did a postdoctoral stay at the Institute of Cancerology and Imnunogenetics at Villejuif, France. From 1996 to 2000 Tamez served as rector of the Autonomous University of Nuevo León from 2000 to 2006 he served as Secretary of Education in the cabinet of Vicente Fox. In January 2007 the Governor of Nuevo León Natividad González Parás designated him as the Nuevo León Secretary of Education replacing former incumbent Yolanda Blanco. In 2009 he was elected via proportional representation to the Chamber of Deputies of Mexico as a New Alliance deputy hence he will be serving during the LXI Legislature of the Mexican Congress.

Tamez co-authored two books in this area of expertise, has presented over 120 papers at national and international conferences and has published over 30 articles in several national and international journals. He has received the Jorge Rosenkranz National Prize in Medical Research and is a member of the Mexican Academy of Sciences OECD: Reyes Tamez

Adrian Bromage

Adrian Stuart Bromage is an Australian businessman and former Australian rules footballer who represented East Fremantle in the Western Australian Football League during the 1990s. From Bruthen, Bromage played senior football for the Bairnsdale Football Club in the Gippsland Football League from the age of 16, he was selected to play for Victoria Country in the Teal Cup, but neglected a career in the Australian Football League for university. Bromage was recruited to East Fremantle in the West Australian Football League for the 1996 season, he played 13 games in 1996, another 16 in 1997, playing in the Sharks' losing grand final team in 1997. He had a stand-out season in 1998, winning both the Sandover Medal, for the best player in the competition, the Simpson Medal, for the best player in the Sharks' premiership-winning grand final team. Bromage left the WAFL at the end of 1998 to pursue business interests in Gippsland. Bromage is the owner of a boutique accommodation complex in Metung, he served as Chairperson of East Gippsland Region Business and Tourism Association and the Shire’s Tourism Advisory Board, as well as the East Gippsland Economic Development Advisory board.

Bromage coached Bairnsdale for five seasons, winning four premierships during that time