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Iqbal Hussain Qureshi
Iqbal Hussain Qureshi (Urdu:اقبال حسين قریشی) 27 September 1937 – 8 December 2012) , best known as I.H. Qureshi, was a Pakistani Nuclear chemistry, nuclear chemist and an :wikt:Emeritus, Emeritus professor of chemistry at the University of Karachi. Qureshi was the principal contributor of scientific understanding of various chemical elements: bismuth, Cobalt-60, cobalt, strontium-90, strontium, Isotopes of thallium, thallium, tritium, iron, rubidium, and zinc. His career was mostly spent with the Government of Pakistan after leaving his research work at the national laboratories, and advising the government on nuclear policy issues. He pushed his influential role at the Pakistan Nuclear Regulatory Authority, Nuclear Regulatory Authority (PNRA) and the peaceful applications of nuclear science. He spent many years as an educator and research scientist at the Pakistan Institute of Engineering and Applied Sciences, Institute of Engineering and Applied Scien ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ajmer
Ajmer is one of the major and oldest cities in the Indian state of Rajasthan and the centre of the eponymous Ajmer District. It is located at the centre of Rajasthan. It is also known as heart of Rajasthan. The city was established as "''Ajayameru''" (translated as "Invincible Hills") by a Chahamana ruler, either Ajayaraja I or Ajayaraja II, and served as their capital until the 12th century CE. Home to the dargah of Moinuddin Chishti, Ajmer is one of the most important destinations of Islamic pilgrimage in South Asia. Ajmer is surrounded by the Aravalli Mountains. Ajmer had been a municipality since 1869. Ajmer has been selected as one of the heritage cities for the HRIDAY and Smart City Mission schemes of the Government of India. History Ajmer was originally known as ''Ajayameru''. The city was founded by an 11th-century Chahamana king Ajaydeva. Historian Dasharatha Sharma notes that the earliest mention of the city's name occurs in Palha's ''Pattavali'', which was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiochemistry
Radiochemistry is the chemistry of radioactive materials, where radioactive isotopes of elements are used to study the properties and chemical reactions of non-radioactive isotopes (often within radiochemistry the absence of radioactivity leads to a substance being described as being ''inactive'' as the isotopes are ''stable''). Much of radiochemistry deals with the use of radioactivity to study ordinary chemical reactions. This is very different from radiation chemistry where the radiation levels are kept too low to influence the chemistry. Radiochemistry includes the study of both natural and man-made radioisotopes. Main decay modes All radioisotopes are unstable isotopes of elements— that undergo nuclear decay and emit some form of radiation. The radiation emitted can be of several types including alpha, beta, gamma radiation, proton, and neutron emission along with neutrino and antiparticle emission decay pathways. 1. α (alpha) radiation—the emission of an alpha parti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zinc
Zinc is a chemical element with the symbol Zn and atomic number 30. Zinc is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodic table. In some respects, zinc is chemically similar to magnesium: both elements exhibit only one normal oxidation state (+2), and the Zn2+ and Mg2+ ions are of similar size.The elements are from different metal groups. See periodic table. Zinc is the 24th most abundant element in Earth's crust and has five stable isotopes. The most common zinc ore is sphalerite (zinc blende), a zinc sulfide mineral. The largest workable lodes are in Australia, Asia, and the United States. Zinc is refined by froth flotation of the ore, roasting, and final extraction using electricity ( electrowinning). Zinc is an essential trace element for humans, animals, plants and for microorganisms and is necessary for prenatal and postnatal development. It ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubidium
Rubidium is the chemical element with the symbol Rb and atomic number 37. It is a very soft, whitish-grey solid in the alkali metal group, similar to potassium and caesium. Rubidium is the first alkali metal in the group to have a density higher than water. On Earth, natural rubidium comprises two isotopes: 72% is a stable isotope 85Rb, and 28% is slightly radioactive 87Rb, with a half-life of 48.8 billion years—more than three times as long as the estimated age of the universe. German chemists Robert Bunsen and Gustav Kirchhoff discovered rubidium in 1861 by the newly developed technique, flame spectroscopy. The name comes from the Latin word , meaning deep red, the color of its emission spectrum. Rubidium's compounds have various chemical and electronic applications. Rubidium metal is easily vaporized and has a convenient spectral absorption range, making it a frequent target for laser manipulation of atoms. Rubidium is not a known nutrient for any living organisms. However, r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tritium
Tritium ( or , ) or hydrogen-3 (symbol T or H) is a rare and radioactive isotope of hydrogen with half-life about 12 years. The nucleus of tritium (t, sometimes called a ''triton'') contains one proton and two neutrons, whereas the nucleus of the common isotope hydrogen-1 (''protium'') contains one proton and zero neutrons, and that of hydrogen-2 (''deuterium'') contains one proton and one neutron. Naturally occurring tritium is extremely rare on Earth. The atmosphere has only trace amounts, formed by the interaction of its gases with cosmic rays. It can be produced artificially by irradiating lithium metal or lithium-bearing ceramic pebbles in a nuclear reactor and is a low-abundance byproduct in normal operations of nuclear reactors. Tritium is used as the energy source in radioluminescent lights for watches, gun sights, numerous instruments and tools, and even novelty items such as self-illuminating key chains. It is used in a medical and scientific setting as a radioacti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isotopes Of Thallium
Thallium (81Tl) has 41 isotopes with atomic masses that range from 176 to 216. 203Tl and 205Tl are the only stable isotopes and 204Tl is the most stable radioisotope with a half-life of 3.78 years. 207Tl, with a half-life of 4.77 minutes, has the longest half-life of naturally occurring Tl radioisotopes. All isotopes of thallium are either radioactive or observationally stable, meaning that they are predicted to be radioactive but no actual decay has been observed. Thallium-202 (half-life 12.23 days) can be made in a cyclotron while thallium-204 (half-life 3.78 years) is made by the neutron activation of stable thallium in a nuclear reactor. In the fully ionized state, the isotope 205Tl becomes beta-radioactive, decaying to 205Pb, but 203Tl remains stable. 205Tl is the decay product of bismuth-209, an isotope that was once thought to be stable but is now known to undergo alpha decay with an extremely long half life of 2.01×1019 y. 205Tl is at the end of the neptunium series ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strontium-90
Strontium-90 () is a radioactive isotope of strontium produced by nuclear fission, with a half-life of 28.8 years. It undergoes β− decay into yttrium-90, with a decay energy of 0.546 MeV. Strontium-90 has applications in medicine and industry and is an isotope of concern in fallout from nuclear weapons, nuclear weapons testing, and nuclear accidents. Radioactivity Naturally occurring strontium is nonradioactive and nontoxic at levels normally found in the environment, but 90Sr is a radiation hazard. 90Sr undergoes β− decay with a half-life of 28.79 years and a decay energy of 0.546 MeV distributed to an electron, an antineutrino, and the yttrium isotope 90Y, which in turn undergoes β− decay with a half-life of 64 hours and a decay energy of 2.28 MeV distributed to an electron, an antineutrino, and 90Zr (zirconium), which is stable. Note that 90Sr/Y is almost a pure beta particle source; the gamma photon emission from the decay of 90Y is so infrequent that it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cobalt-60
Cobalt-60 (60Co) is a synthetic radioactive isotope of cobalt with a half-life of 5.2713 years. It is produced artificially in nuclear reactors. Deliberate industrial production depends on neutron activation of bulk samples of the monoisotopic and mononuclidic cobalt isotope . (PDF also located aCanadian Nuclear FAQ Measurable quantities are also produced as a by-product of typical nuclear power plant operation and may be detected externally when leaks occur. In the latter case (in the absence of added cobalt) the incidentally produced is largely the result of multiple stages of neutron activation of iron isotopes in the reactor's steel structures via the creation of its precursor. The simplest case of the latter would result from the activation of . undergoes beta decay to the stable isotope nickel-60 (). The activated nickel nucleus emits two gamma rays with energies of 1.17 and 1.33 MeV, hence the overall equation of the nuclear reaction (activation and decay) is: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bismuth
Bismuth is a chemical element with the Symbol (chemistry), symbol Bi and atomic number 83. It is a post-transition metal and one of the pnictogens, with chemical properties resembling its lighter group 15 siblings arsenic and antimony. Elemental bismuth occurs naturally, and its sulfide and oxide forms are important commercial ores. The free element is 86% as dense as lead. It is a brittle metal with a silvery-white color when freshly produced. Passivation (chemistry), Surface oxidation generally gives samples of the metal a somewhat rosy cast. Further oxidation under heat can give bismuth a vividly Iridescence, iridescent appearance due to thin-film interference. Bismuth is both the most Diamagnetism, diamagnetic element and one of the least Thermal conductivity, thermally conductive metals known. Bismuth was long considered the element with the highest atomic mass whose nuclei do not spontaneously decay. However, in 2003 it was discovered to be extremely weakly radioactive. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Karachi
The University of Karachi ( sd, ; informally Karachi University, KU, or UoK) is a public research university located in Karachi, Sindh, Pakistan. Established in June 1951 by an act of Parliament and as a successor to the University of Sindh (which is now located in Jamshoro), the university is a "Sindh Government University" and designed by Mohsin Baig as its chief architect. With a total student body of 41,000 full-time students and a campus size spanning over 1200 acres, Karachi University is one of the largest universities in Pakistan with a distinguished reputation for multi-disciplinary research in science and technology, medical, and social sciences. The university has over 53 Departments and 19 research institutes operating under nine faculties. There are over 893 academics and more than 2500 supporting staff working for the university. In 2008, the university was named for the first time by ''THE-QS World University Rankings'' among the top 600 universities in the world ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fellow Of The Pakistan Academy Of Sciences
The Pakistan Academy of Sciences ( ur, ) (abbreviated as: PAS), is a learned society of sciences, which described itself as "a repository of the highest scientific talent available in the country." Established in 1953 in Lahore, Punjab, the Academy acts as a consultative forum and scientific advisor to the Pakistan government on important aspects on the affairs of all forms of science– the social and physical sciences. Regulating affairs of by its Charter and laws approved by the fellows, the Academy is governed by a council that is chaired by its President. Due to its utmost importance, the fellowship of the academy is extremely restricted, only to the scholars of the high merit who have made outstanding contributions to the advancement of scientific knowledge. As of current, Qasim Jan is the President of the Pakistan Academy of Sciences (PAS) who took after succeeding Anwar Nasim in 2017. History The idea of establishing the Academy was mooted in November 1947 when ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
