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  • nuclear
  • Most radioisotopes produced in quantity are made in the nuclear reactor by one of four reactions (Table 1): neutron-gamma, neutron-proton, neutron-alpha, and neutron-fission. (persianblog.ir)
  • Problems with the world production and supply of molybdenum are leading to shortages of radioisotopes for nuclear medicine imaging tests, according to an editorial in the journal Nuclear Medicine Communications , official journal of the British Nuclear Medicine Society (BNMS). (medindia.net)
  • In the last two years, shutdowns of reactors in Canada and the Netherlands have led to disruptions in the supply of molybdenum to hospital nuclear medicine departments in the United Kingdom, Europe, and North America. (medindia.net)
  • Whereas the full "active" reactor system in a nuclear thermal rocket can be expected to generate over a gigawatt, a radioisotope generator might get 5 kW. (wikipedia.org)
  • As use of and experience with radioisotopes became more widespread in medicine, radioimmunoassay generally transferred from nuclear medicine to clinical pathology. (wikipedia.org)
  • solders
  • Lead-free solders have been increasing in use due to regulatory requirements plus the health and environmental benefits of avoiding lead-based electronic components. (wikipedia.org)
  • Most lead-free replacements for conventional 60/40 and 63/37 Sn-Pb solder have melting points from 5 to 20 °C higher, though there are also solders with much lower melting points. (wikipedia.org)
  • widespread
  • Galena, a principal ore of lead, often bears silver, interest in which helped initiate widespread extraction and use of lead in ancient Rome. (wikipedia.org)
  • The widespread use of this popular lead-free solder alloy family is based on the reduced melting point of the Sn-Ag-Cu ternary eutectic behavior (217 ˚C), which is below the 22/78 Sn-Ag (wt. (wikipedia.org)
  • metals
  • One of the oldest metals used by humanity, lead was known to the ancient Egyptians and Babylonians. (thefreedictionary.com)
  • Some rarer metals are denser: tungsten and gold are both 19.3 g/cm3, and osmium-the densest metal known-has a density of 22.59 g/cm3, almost twice that of lead. (wikipedia.org)
  • galena
  • Although lead is seldom found uncombined in nature, its compounds are widely distributed throughout the world, principally in the ores galena galena or lead glance, lustrous, blue-gray mineral crystallizing usually in cubes, sometimes in octahedrons. (thefreedictionary.com)
  • and anglesite anglesite , pale green, blue, yellow-to-white, or colorless mineral, a sulfate of lead, PbSO 4 , that is formed by oxidation of galena, crystallizing in the orthorhombic system and occurring also in granular or massive form. (thefreedictionary.com)
  • ions
  • Rather than having a diamond cubic structure, lead forms metallic bonds in which only the p-electrons are delocalized and shared between the Pb2+ ions. (wikipedia.org)
  • Tin and lead are both capable of forming +2 ions. (wikipedia.org)
  • found
  • Like most radioisotopes found in the radium series, 206Pb was initially named as a variation of radium, specifically radium G. It is the decay product of both 210Po (historically called radium F) by alpha decay, and the much rarer 206Tl (radium EII) by beta decay. (wikipedia.org)
  • relatively
  • Radioisotopes are produced by irradiation of the elements with high-energy particles (protons, deuterons) in accelerators and in the high-intensity neutron fluxes of relatively small research-type reactors. (persianblog.ir)
  • Lead is a relatively unreactive post-transition metal. (wikipedia.org)
  • composition
  • Since this decay takes place at a constant rate, it is possible to predict either the maximum age of a lead-containing rock or its composition at some earlier date, as long as the rock has not been chemically altered. (thefreedictionary.com)
  • thermal
  • It is notable for its unusually low neutron capture cross section (even lower than that of deuterium in the thermal spectrum), making it of interest for lead-cooled fast reactors. (wikipedia.org)
  • usually
  • As other applications developed the physician or group that had developed knowledge of and experience with radioisotopes usually provided the new service. (wikipedia.org)
  • density
  • This density is the origin of the idiom to go over like a lead balloon. (wikipedia.org)
  • Tin has a density of 7.26 grams per cubic centimeter, and lead has a density of 11.3 grams per cubic centimeter. (wikipedia.org)
  • carbon
  • The carbon group is a periodic table group consisting of carbon (C), silicon (Si), germanium (Ge), tin (Sn), lead (Pb), and flerovium (Fl). (wikipedia.org)
  • power
  • The even shorter half-life element fermium has also been suggested Another drawback to the use of radioisotopes in rockets is an inability to change the operating power. (wikipedia.org)
  • Radioisotope power has been used on eight Earth orbiting missions, eight missions travelling to each of the outer planets as well as each of Apollo missions following 11 to Earth's moon. (wikipedia.org)
  • often
  • To lead the radioisotopes of often considered wide viscosities on the NIRF books, we moved positive and bacterial good to their establishing condos, download Mixed models for the of brand in mobile recording, and the available doctrinal voltage of PET care. (intervista-institute.com)
  • Often a particular application drove the introduction of radioisotopes into a health care facility. (wikipedia.org)
  • applications
  • Some of the earliest applications of radioisotopes were therapy of hematologic malignancies and therapy of both benign and malignant thyroid disease. (wikipedia.org)
  • Lead-free solder may be less desirable for critical applications, such as aerospace and medical projects, because its properties are less thoroughly known. (wikipedia.org)
  • half-life
  • Twenty neptunium radioisotopes have been characterized, with the most stable being 237 Np with a half-life of 2.14 million years, 236 Np with a half-life of 154,000 years, and 235 Np with a half-life of 396.1 days. (wikipedia.org)
  • Next, the capsule is irradiated for the optimum time period, determined by the half-life of the desired radioisotope, the absorption cross section of the target atom, and the growth of possible undesired impurities. (persianblog.ir)
  • The longest-lived radioisotopes are 205Pb with a half-life of ≈15.3 million years and 202Pb with a half-life of ≈53,000 years. (wikipedia.org)
  • development
  • Benedict Cassen's work with a directional probe lead to the development of the first imaging with a rectilinear scanner. (wikipedia.org)
  • medical
  • The BNMS will play a central role in minimizing the impact of the molybdenum shortage on patient services while advocating investment in alternative means of meeting the critical demand for medical radioisotopes. (medindia.net)
  • Initial introduction of radioisotopes into medicine required individuals to acquire of a considerable background information which was foreign to their medical training. (wikipedia.org)
  • forms
  • Lead forms one hydride, which has the formula PbH4. (wikipedia.org)
  • Lead forms dihalides and tetrahalides with fluorine and chlorine, and forms a tetrabromide and a lead diiodide, although the tetrabromide and tetraiodide of lead are unstable. (wikipedia.org)
  • health
  • The journal is published by Lippincott Williams & Wilkins, a part of Wolters Kluwer Health, a leading provider of information and business intelligence for students, professionals, and institutions in medicine, nursing, allied health, pharmacy and the pharmaceutical industry. (medindia.net)
  • Although
  • This could lead to a tiny amount of net thrust being generated, although all calculations to date suggest it is not enough in itself to fully explain the effect. (wikipedia.org)
  • crystal structure
  • Zircon crystals grow between 600 and 1100 °C, while lead is retained within the crystal structure below 800 °C (see Closure temperature). (wikipedia.org)
  • interest
  • The rule states that this would lead to a net price or "Hotelling rent" for it that rose annually at a rate equal to the rate of interest, reflecting the increasing scarcity of the resource. (wikipedia.org)
  • soft
  • Lead is a neurotoxin that accumulates in soft tissues and bones, damages the nervous system, and causes blood disorders. (wikipedia.org)
  • electrons
  • The reaction of the hydrocarbon with the oxide material surface upon exposure (via metal dopant) leads to the re-injection of electrons into the oxide bulk. (ox.ac.uk)
  • nuclear
  • For over 50 years PerkinElmer has been a leading supplier of radiochemicals, liquid scintillation cocktails, vials and nuclear counting detection instruments. (perkinelmer.co.uk)
  • Iodine-125 (125I) is a radioisotope of iodine which has uses in biological assays, nuclear medicine imaging and in radiation therapy as brachytherapy to treat a number of conditions, including prostate cancer, uveal melanomas, and brain tumors. (wikipedia.org)
  • A staunch supporter of nuclear power, Ahmad has led Pakistan's delegation in many international and national forums and conferences in the issues of peaceful use of nuclear energy. (wikipedia.org)
  • similar
  • Recently, geochronologists researching the Great Dyke, a Precambrian layered mafic and ultramafic intrusion of Zimbabwe in southeast Africa, have documented a similar pattern of radioisotope discordance. (icr.org)
  • Consistent with this recommendation, it was announced on March 1, 2011 that the NIAC was to be revived with similar goals leading to the establishment in 2011 of a project within the NASA Office of Chief Technologist, the NASA Innovative Advanced Concepts, maintaining the acronym NIAC. (wikipedia.org)
  • work
  • Later, Abdus Salam led the work on simultaneity where the TPG finished the calculations on how weapon would be detonated from several points at same time. (wikipedia.org)
  • It operated for 43 years, producing radioisotopes, undertaking fuels and materials development work for CANDU reactors, and providing neutrons for physics experiments. (wikipedia.org)
  • In August 1945, 127 missile specialists led by Wernher von Braun signed work contracts with the U.S. Army's Ordnance Corps. (wikipedia.org)
  • studies
  • Considering the in vitro antileishmanial potential of 2-hydroxy-3-phenylsulfanylmethyl-[1,naphthoquinones and their structure-activity relationships, novel lead candidates could be exploited in future drug design studies for leishmaniasis. (jove.com)
  • made
  • FIG. 6 ( a ) shows an example using 103 Pd as a radiation nuclide, in which a radiation seed comprising graphite pellet 25 coated with 103 Pd and an X-ray marker 23 made of lead is encapsulated in a titanium tube 20 of 0.8 mm in diameter and 4.5 mm in length with sealed ends. (google.com)
  • Mission
  • Rodríguez-Arroyo is the Communications System Lead Engineer for the Lunar Reconnaissance Orbiter (LRO) Mission, to be launched in 2008. (wikipedia.org)
  • The Lunar Lander was a robotic mission intended to send a lander vehicle to the Moon, led by ESA's Human Spaceflight and Operations directorate. (wikipedia.org)
  • Passively safe' components are the concrete walls and the steel liner, but in order to fulfil its mission active systems have to operate, e.g. valves to ensure the closure of the piping leading outside the containment, feedback of reactor status to external instrumentation and control (I&C) both of which may require external power to function. (wikipedia.org)
  • The selected mission will be the fourth in NASA's New Frontiers portfolio, a series of principal investigator-led planetary science investigations that fall under a development cost cap of approximately $850 million. (wikipedia.org)