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Naturally Occurring Radioactive Material
Naturally occurring radioactive materials (NORM) and technologically enhanced naturally occurring radioactive materials (TENORM) consist of materials, usually industrial wastes or by-products enriched with radioactive materials, radioactive elements found in the environment, such as uranium, thorium and potassium-40 (a long-lived beta emitter that is part of natural potassium on earth) and any of the products of the decay chains of the former two, such as radium and radon. Produced water discharges and spills are a good example of entering NORMs into the surrounding environment. Natural radioactive materials, radioactive elements are present in very low concentrations in Earth's crust, and are brought to the surface through human activities such as oil and gas exploration, drilling for geothermal energy or mining, and through natural processes like leakage of radon gas to the atmosphere or through dissolution in ground water. Another example of TENORM is coal ash produced from co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Industrial Waste
Industrial waste is the waste produced by industrial activity which includes any material that is rendered useless during a manufacturing process such as that of factories, mills, and mining operations. Types of industrial waste include dirt and gravel, masonry and concrete, scrap metal, oil, solvents, chemicals, scrap lumber, even vegetable matter from restaurants. Industrial waste may be solid, semi-solid or liquid in form. It may be hazardous waste (some types of which are toxicity, toxic) or non-hazardous waste. Industrial waste may pollute the nearby soil or adjacent water bodies, and can contaminate groundwater, lakes, streams, rivers or coastal waters. Industrial waste is often mixed into municipal waste, making accurate assessments difficult. An estimate for the US goes as high as 7.6 billion tons of industrial waste produced annually, as of 2017. Most countries have enacted legislation to deal with the problem of industrial waste, but strictness and compliance regimes var ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apatite
Apatite is a group of phosphate minerals, usually hydroxyapatite, fluorapatite and chlorapatite, with high concentrations of Hydroxide, OH−, Fluoride, F− and Chloride, Cl− ion, respectively, in the crystal. The formula of the admixture of the three most common Endmember (mineralogy), endmembers is written as Calcium, Ca10(Phosphate, PO4)6(OH,F,Cl)2, and the crystal unit cell formulae of the individual minerals are written as Ca10(PO4)6(OH)2, Ca10(PO4)6F2 and Ca10(PO4)6Cl2. The mineral was named apatite by the German geologist Abraham Gottlob Werner in 1786, although the specific mineral he had described was reclassified as fluorapatite in 1860 by the German mineralogist Karl Friedrich August Rammelsberg. Apatite is often mistaken for other minerals. This tendency is reflected in the mineral's name, which is derived from the Greek word ἀπατάω (apatáō), which means ''to deceive''. Geology Apatite is very common as an accessory mineral in igneous and metamorphic roc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tulane Law Review
The ''Tulane Law Review'', a publication of the Tulane University Law School, was founded in 1916, and is currently published five times annually. The ''Law Review'' has an international circulation. History The ''Law Review'' was started as the ''Southern Law Quarterly'' by Rufus Carrollton Harris, the school's twelfth dean. Charles E. Dunbar, Jr., the civil service reformer who became a Tulane law professor, served on the board of advisory editors of the ''Tulane Law Review'' from its inception until his death in 1959. A 1937 ''Time'' magazine A magazine is a periodical literature, periodical publication, print or digital, produced on a regular schedule, that contains any of a variety of subject-oriented textual and visual content (media), content forms. Magazines are generally fin ... about Rufus Harris describes the ''Tulane Law Review'' as "nationally famed". The ''Law Review'' was most recently cited by the United States Supreme Court on April 27, 2010. Members ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bone Seeker
A bone seeker is an element, often a radioisotope, that tends to accumulate in the bones of humans and other animals when introduced into the body. For example, strontium and radium are chemically similar to calcium and can replace the calcium in bones. Plutonium is also a bone seeker, though the mechanism by which it accumulates in bone tissue is unknown. Radioactive bone seekers are particular health risks as they irradiate surrounding tissue, though this can be useful for radiotherapy, such as in the case of radium-223. Stable bone seekers can also be harmful: excessive strontium absorption has been linked with increased levels of rickets. The salt strontium ranelate, however, is a bone seeker which is sometimes used to strengthen bones as a treatment for osteoporosis. Bone seekers have been proposed as a method of delivering antibiotic An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Respirator
A respirator is a device designed to protect the wearer from inhaling hazardous atmospheres including lead, lead fumes, vapors, gases and particulate matter such as dusts and airborne pathogens such as viruses. There are two main categories of respirators: the ''air-purifying respirator'', in which respirable air is obtained by filtering a contaminated atmosphere, and the ''air-supplied respirator'', in which an alternate supply of breathable air is delivered. Within each category, different techniques are employed to reduce or eliminate noxious airborne contaminants. Air-purifying respirators range from relatively inexpensive, single-use, disposable face masks, known as filtering facepiece respirators, reusable models with replaceable cartridges called elastomeric respirators, to powered air-purifying respirators (PAPR), which use a pump or fan to constantly move air through a filter and supply purified air into a mask, helmet or hood. History Earliest records to 19th c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lead-206
Lead (82Pb) has four observationally stable isotopes: 204Pb, 206Pb, 207Pb, 208Pb. Lead-204 is entirely a primordial nuclide and is not a radiogenic nuclide. The three isotopes lead-206, lead-207, and lead-208 represent the ends of three decay chains: the uranium series (or radium series), the actinium series, and the thorium series, respectively; a fourth decay chain, the neptunium series, terminates with the thallium isotope 205Tl. The three series terminating in lead represent the decay chain products of long-lived primordial 238U, 235U, and 232Th. Each isotope also occurs, to some extent, as primordial isotopes that were made in supernovae, rather than radiogenically as daughter products. The fixed ratio of lead-204 to the primordial amounts of the other lead isotopes may be used as the baseline to estimate the extra amounts of radiogenic lead present in rocks as a result of decay from uranium and thorium. (See lead–lead dating and uranium–lead dating.) The longest-liv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polonium-210
Polonium-210 (210Po, Po-210, historically radium F) is an isotope of polonium. It undergoes alpha decay to stable 206Pb with a half-life of 138.376 days (about months), the longest half-life of all naturally occurring polonium isotopes (210–218Po). First identified in 1898, and also marking the discovery of the element polonium, 210Po is generated in the decay chain of uranium-238 and radium-226. 210Po is a prominent contaminant in the environment, mostly affecting seafood and tobacco. Its extreme toxicity is attributed to intense radioactivity, mostly due to alpha particles, which easily cause radiation damage, including cancer in surrounding tissue. The specific activity of is 166 TBq/g, i.e., . At the same time, 210Po is not readily detected by common radiation detectors, because its gamma rays have a very low energy. Therefore, can be considered as a quasi-pure alpha emitter. History In 1898, Marie and Pierre Curie discovered a strongly radioactive substance ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bismuth-210
Bismuth (83Bi) has 41 known isotopes, ranging from 184Bi to 224Bi. Bismuth has no stable isotopes, but does have one very long-lived isotope; thus, the standard atomic weight can be given as . Although bismuth-209 is now known to be radioactive, it has classically been considered to be a stable isotope because it has a half-life of approximately 2.01×1019 years, which is more than a billion times the age of the universe. Besides 209Bi, the most stable bismuth radioisotopes are 210mBi with a half-life of 3.04 million years, 208Bi with a half-life of 368,000 years and 207Bi, with a half-life of 32.9 years, none of which occur in nature. All other isotopes have half-lives under 1 year, most under a day. Of naturally occurring radioisotopes, the most stable is radiogenic 210Bi with a half-life of 5.012 days. 210mBi is unusual for being a nuclear isomer with a half-life multiple orders of magnitude longer than that of the ground state. List of isotopes , -id=Bismuth-184 , 184B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lead-210
Lead (82Pb) has four observationally stable isotopes: 204Pb, 206Pb, 207Pb, 208Pb. Lead-204 is entirely a primordial nuclide and is not a radiogenic nuclide. The three isotopes lead-206, lead-207, and lead-208 represent the ends of three decay chains: the uranium series (or radium series), the actinium series, and the thorium series, respectively; a fourth decay chain, the neptunium series, terminates with the thallium isotope 205Tl. The three series terminating in lead represent the decay chain products of long-lived primordial 238U, 235U, and 232Th. Each isotope also occurs, to some extent, as primordial isotopes that were made in supernovae, rather than radiogenically as daughter products. The fixed ratio of lead-204 to the primordial amounts of the other lead isotopes may be used as the baseline to estimate the extra amounts of radiogenic lead present in rocks as a result of decay from uranium and thorium. (See lead–lead dating and uranium–lead dating.) The longest-live ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radium-228
Radium (88Ra) has no stable or nearly stable isotopes, and thus a standard atomic weight cannot be given. The longest lived, and most common, isotope of radium is 226Ra with a half-life of . 226Ra occurs in the decay chain of 238U (often referred to as the radium series). Radium has 34 known isotopes from 201Ra to 234Ra. In the early history of the study of radioactivity, the different natural isotopes of radium were given different names, as it was not until Frederick Soddy's scientific career in the early 1900s that the concept of isotopes was realized. In this scheme, Ra was named actinium X (AcX), Ra thorium X (ThX), Ra radium (Ra), and Ra mesothorium 1 (MsTh). When it was realized that all of these are isotopes of the same element, many of these names fell out of use, and "radium" came to refer to all isotopes, not just Ra, though mesothorium 1 in particular was still used for some time, with a footnote explaining that it referred to Ra. Some of radium-226's deca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radium-226
Radium-226 () is the longest-lived isotope of radium, with a half-life of 1600 years. It is an intermediate product in the decay chain of uranium-238; as such, it can be found naturally in uranium-containing minerals. Occurrence and decay occurs in the decay chain of uranium-238 (), which is the most common naturally occurring isotope of uranium. It undergoes alpha decay to radon-222, which is also radioactive; the decay chain ultimately terminates at lead-206. Because of its occurrence in the decay chain, exists naturally at low concentrations in uranium-containing minerals, soil, and groundwater. Historical uses Following its discovery by Marie and Pierre Curie in 1898, radium (principally ) has had a number of uses. In the early 20th century, when the hazards of radiation were not well-known, radium was commonly used in consumer items such as toothpaste and hair creams. Radium was also formerly used as a radiation source for cancer treatment, but has since been replac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North Dakota
North Dakota ( ) is a U.S. state in the Upper Midwest, named after the indigenous Dakota people, Dakota and Sioux peoples. It is bordered by the Canadian provinces of Saskatchewan and Manitoba to the north and by the U.S. states of Minnesota to the east, South Dakota to the south, and Montana to the west. North Dakota is part of the Great Plains region, characterized by broad prairies, steppe, temperate savanna, badlands, and farmland. North Dakota is the List of U.S. states and territories by area, 19th-largest state by area, but with a population of just under 800,000, the List of U.S. states and territories by population, fourth-least populous and List of U.S. states by population density, fourth-least densely populated. The List of capitals in the United States, state capital is Bismarck, North Dakota, Bismarck and the List of cities in North Dakota, most populous city is Fargo, North Dakota, Fargo, which accounts for nearly a fifth of the state's population; both cities ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
