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Technetium

Technetium is a chemical element with the symbol Tc and atomic number 43. It is the lightest element. Nearly all technetium is produced as a synthetic element, only about 18,000 tons are estimated to exist at any given time in the Earth's crust. Occurring technetium is a spontaneous fission product in uranium ore and thorium ore, the most common source, or the product of neutron capture in molybdenum ores; this silvery gray, crystalline transition metal lies between manganese and rhenium in group 7 of the periodic table, its chemical properties are intermediate between those of these two adjacent elements. The most common occurring isotope is 99Tc. Many of technetium's properties were predicted by Dmitri Mendeleev before the element was discovered. Mendeleev noted a gap in his periodic table and gave the undiscovered element the provisional name ekamanganese. In 1937, technetium became the first predominantly artificial element to be produced, hence its name. One short-lived gamma ray-emitting nuclear isomer of technetium—technetium-99m—is used in nuclear medicine for a wide variety of diagnostic tests, such as bone cancer diagnoses.

The ground state of this nuclide, technetium-99, is used as a gamma-ray-free source of beta particles. Long-lived technetium isotopes produced commercially are by-products of the fission of uranium-235 in nuclear reactors and are extracted from nuclear fuel rods; because no isotope of technetium has a half-life longer than 4.21 million years, the 1952 detection of technetium in red giants helped to prove that stars can produce heavier elements. From the 1860s through 1871, early forms of the periodic table proposed by Dmitri Mendeleev contained a gap between molybdenum and ruthenium. In 1871, Mendeleev predicted this missing element would occupy the empty place below manganese and have similar chemical properties. Mendeleev gave it the provisional name ekamanganese because the predicted element was one place down from the known element manganese. Many early researchers, both before and after the periodic table was published, were eager to be the first to discover and name the missing element.

Its location in the table suggested that it should be easier to find than other undiscovered elements. German chemists Walter Noddack, Otto Berg, Ida Tacke reported the discovery of element 75 and element 43 in 1925, named element 43 masurium; the group bombarded columbite with a beam of electrons and deduced element 43 was present by examining X-ray emission spectrograms. The wavelength of the X-rays produced is related to the atomic number by a formula derived by Henry Moseley in 1913; the team claimed to detect a faint X-ray signal at a wavelength produced by element 43. Experimenters could not replicate the discovery, it was dismissed as an error for many years. Still, in 1933, a series of articles on the discovery of elements quoted the name masurium for element 43. Whether the 1925 team did discover element 43 is still debated; the discovery of element 43 was confirmed in a 1937 experiment at the University of Palermo in Sicily by Carlo Perrier and Emilio Segrè. In mid-1936, Segrè visited the United States, first Columbia University in New York and the Lawrence Berkeley National Laboratory in California.

He persuaded cyclotron inventor Ernest Lawrence to let him take back some discarded cyclotron parts that had become radioactive. Lawrence mailed him a molybdenum foil, part of the deflector in the cyclotron. Segrè enlisted his colleague Perrier to attempt to prove, through comparative chemistry, that the molybdenum activity was indeed from an element with the atomic number 43. In 1937, they succeeded in isolating the isotopes technetium-95m and technetium-97. University of Palermo officials wanted them to name their discovery "panormium", after the Latin name for Palermo, Panormus. In 1947 element 43 was named after the Greek word τεχνητός, meaning "artificial", since it was the first element to be artificially produced. Segrè met Glenn T. Seaborg, they isolated the metastable isotope technetium-99m, now used in some ten million medical diagnostic procedures annually. In 1952, astronomer Paul W. Merrill in California detected the spectral signature of technetium in light from S-type red giants.

The stars were near the end of their lives, yet were rich in this short-lived element, indicating that it was being produced in the stars by nuclear reactions. This evidence bolstered the hypothesis that heavier elements are the product of nucleosynthesis in stars. More such observations provided evidence that elements are formed by neutron capture in the s-process. Since that discovery, there have been many searches in terrestrial materials for natural sources of technetium. In 1962, technetium-99 was isolated and identified in pitchblende from the Belgian Congo in small quantities; the Oklo natural nuclear fission reactor contains evidence that significant amounts of technetium-99 were produced and have since decayed into ruthenium-99. Technetium is a silvery-gray radioactive metal with an appearance similar to platinum obtained as a gray powder; the crystal structure of the pure metal is hexagonal close-packed. Atomic technetium has characteristic emission lines at wavelengths of 363.3 n

Neeraj Prabhu

Neeraj Vijay Prabhu is an Indian-born former English cricketer. Prabhu was a right-handed batsman, he was born at Maharashtra. Having played Second XI cricket for Warwickshire from 1996 to 1998, Prabhu made his debut in Minor counties cricket for Herefordshire in the 1999 MCCA Knockout Trophy against the Worcestershire Cricket Board. In that same season, he made his debut in the Minor Counties Championship against Wiltshire, he played Minor counties cricket for Herefordshire from 1999 to 2002, making thirteen Minor Counties Championship appearances and ten MCCA Knockout Trophy appearances. He made two List A appearances during his time at Herefordshire; the first of these came against the Sussex Cricket Board at Stowe Lane, Colwall, in the 2000 NatWest Trophy. In a match which Herefordshire lost by 6 runs, Prabhu scored 24 runs in Herefordshire's unsuccessful chase, before he was dismissed by Steven Ades, his second appearance in that format came against the Gloucestershire Cricket Board at The Park, Brockhampton, in the 2001 Cheltenham & Gloucester Trophy.

In a match which Herefordshire won by 5 wickets, Prabhu wasn't required to bat in Herefordshire's successful chase. After his cricket career, Prabhu worked in the banking sector, he is now head of mathematics at The British School Warsaw. Neeraj Prabhu at ESPNcricinfo

Namutoni

Namutoni is a restcamp on the edge of Etosha pan in the Oshikoto Region in northern Namibia. It is one of the entrance gates to Etosha National Park; the most prominent structure at Namutoni is Fort Namutoni, built in 1896. It was a German Police post and, as part of the Red Line, a veterinary control point; the Red Line at that time extended to Okaukuejo in Otjituuo in the east. Namutoni was used to hold English prisoners in World War I; the original fort was destroyed in 1904 following the Battle of Namutoni and rebuilt a year or two later. Fort Namutoni was declared a National Monument in 1947 by the South West Africa Monuments Council; the current fort was restored to its present state in 1957 and now serves as a lodge and view point for visitors to Etosha National Park. Okaukuejo

Florence Noiville

Florence Noiville, a French author and journalist, is a long time staff writer for Le Monde and editor of foreign fiction for Le Monde des Livres, the literary supplement of Le Monde. After attending Sciences Po, the international business school HEC Paris, receiving her Masters' in Business Law, Noiville began her professional career in an American corporation, working in the financial sector. Against all odds, she moved four years from numbers to letters, leading her career towards what had always interested her: writing and literature. Since 1994 she has worked as a journalist and literary critic for the French newspaper Le Monde, she has done numerous interviews and profiles including Saul Bellow, Imre Kertész, John le Carré, Mario Vargas Llosa, Herta Müller. Her interviews and portraits of writers were published in English in Literary Miniatures. From 2007 to 2010, she hosted a literary show on French television channel LCI entitled "Le Monde des Livres". Among the authors she invited to her show are: Claude Lanzmann, Joseph Stiglitz, Paul Auster, Umberto Eco...

In 2007-2008, she was a judge for the Independent Foreign Fiction Prize organized by The Independent and the British Council in London. Florence Noiville is the author of four novels, two biographies and a pamphlet on the excesses of capitalism, called I Went to Business School and I apologize, her novels combine neuroscience. Her books are translated into 13 languages. Florence Noiville is married to Martin Hirsch, they live in Paris with their three children. The Gift, Northwestern University Press, 2012 The Attachment, Seagull Books, 2014 A Cage in Search of a Bird, Seagull Books, 2016 Confessions d'une Cleptomane, Stock, 2018 Isaac B. Singer, A Life, Farrar and Giroux, 2006. Biographical Story Award 2014. Nina Simone. Love me or leave me, Tallandier, 2019, co-written with her daughter Mathilde Hirsch. Simone Veil Prize 2019. I Went to Business School and I Apologize, Stock, 2009 Literary Miniatures, Seagull Books, 2017 Passions Couleurs, Gallimard Jeunesse, 1998, a conversation with Jacqueline Duhême Je cherche les clés du paradis, L'École des loisirs, 1999 La Mythologie grecque, Actes Sud Junior, 2000 Les Héros grecs, Actes Sud Junior, 2002 La Mythologie romaine, Actes Sud Junior, 2003 Histoires insolites des saints du calendrier, Actes Sud Junior, 2004 Bébé Jules qui ne voulait pas naître, Gallimard Jeunesse, 2005 Petites histoires de derrières les fourneaux, Actes Sud Junior, 2006 Et toi, ta grand-mère?, Actes Sud Junior, 2008

Bangladesh–Iraq relations

Bangladesh–Iraq relations refer to the bilateral relations between Bangladesh and Iraq. After the Independence of Bangladesh in 1971, Iraq recognized Bangladesh as a sovereign country on 8 July 1972, becoming the first Arab country to do so. Bangladesh provided soldiers for patrolling the Iran–Iraq border in the aftermath of the Iran–Iraq War as part of the United Nations Iran–Iraq Military Observer Group. Bangladesh Army was part of the coalition in Operation Desert Storm. Bangladesh's Expatriates Welfare and Overseas Employment Minister Khandaker Mosharraf Hossain and Iraq's Labour and Social Affairs Minister Nassar-Al-Rubaiee signed an Memorundam of Understanding to import labour from Bangladesh in 2009. Iraq has a resident embassy in Bangladesh. Bangladesh has expressed support for the territorial integrity of Iraq in 2008. Bangladesh has stopped after the war. In 2009 Bangladesh started to send workers to Iraq again. Bangladeshi workers in Iraq have faced violence from both security forces and rebels.

As of 2016, 43 thousand Bangladeshis are employed in Iraq. Hossain, Ishtiaq. "Bangladesh and the Gulf War: Response of a Small State". Pakistan Horizon. 50: 39–55. JSTOR 41393571

London Arch

London Arch is an offshore natural arch formation in the Port Campbell National Park, Australia. The arch is a significant tourist attraction along the Great Ocean Road near Port Campbell in Victoria; this stack was formed by a gradual process of erosion, until 1990 formed a complete double-span natural bridge. The span closer to the shoreline collapsed unexpectedly on 15 January 1990, leaving two tourists stranded on the outer span before being rescued by police helicopter. No one was injured in the event. Prior to the collapse, the arch was known as London Bridge because of its similarity to its namesake; the Twelve Apostles, Victoria Loch Ard Gorge The Gibson Steps The Grotto Percé Rock, another double arch where one collapsed Media related to London Arch at Wikimedia Commons Official Website for 12 Apostles Region of Victoria Why do arches fall? on the website of Geoscience Australia