Radio-activity

The Waste Isolation Pilot Plant (WIPP) is in an excavated salt cavern in southern New Mexico, twenty-seven miles from Carlsbad. The WIPP site is 2,000 yards underground, and defense waste is being placed. There are plans to place there about 6 million cubic feet of material there containing fewer than five million curies of radio activity. 

Provision of emergency equipment for specialized building activities (i.e. chemical, radio-active contamination) ... 

Among the causes producing irreversibility w7e may instance the forces depending on friction in solids, viscosity of liquids imperfect elasticity of solids inequalities of temperature (leading to heat conduction) set up by stresses in solids and fluids generation of heat by electric currents diffusion chemical and radio-active changes and absorption of radiant energy. 

Reinhoudt et al. also reported water-soluble pseudorotaxane-terminated dendrimers possessing a radio-active metal core for radiotherapeutical applications... 

Crookes W (1900) Radio-activity of Uranium. Proc R Soc London 66 409-422... 

Strutt RJ (1905) On the radio-active minerals. Proc R Soc London 76 88-101... 

Immediately that the parent is incorporated into the crystal it will start to decay to the daughter. At secular equilibrium the (radio)activity of parent and daughter, will be equal, such that ... 

Boltwood BB (1907) Note on a new radio-active element. Amer J Sci 24 370-372... 

In the case of radio-active decay the rate is often expressed by the half-life, namely, die time required for half of the reactant to disappear. From Gq. (22) the half-life is given by t /2 = (hr 2)1 k. 

The better known rhenium(V) chemistry is of great interest, not only because it resembles the second-row congener technetium and easily permits non-radio-active model studies for technetium. 186Re and 188Re are attractive isotopes for therapeutic radiopharmaceuticals. 99mTc and 186Re can be considered to be a matched pair for diagnostics and therapy. 

B.E.J. Pagel The G-Dwarf Problem and Radio-Active Cosmochronology . In Evolutionary Phenomena in Galaxies, Summer School at Puerto de la Cruz, Spain, July i 15, 1988, ed. by J.E. Beckman, B.E.J. Pagel (Cambridge University Press, Cambridge, New York 1989), pp. 201-223... 

Fig. 10. Diffusion of auxin into agar blocks in three hours from corn coleoptile tips. The numbers given are curvatures obtained from a standard auxin test, i,.e. a measure for the auxin diffused into the agar. (A) dark control bisecting does not significantly reduce the total amount of auxin. Unilateral bluelight (B) the total amount of flavin is not significantly reduced by irradiation (C) partial bisecting indicates strong lateral-basipetal auxin transport23). (D) Radio-actively labeled auxin, symmetrically applied to the coleoptile tip, proves the conclusion drawn from experiment (C)13 G...

To take radio-activity alone. .. perhaps there is no discovery of modern times which has so disorganized the fertile but by no means plastic brain and imagination of the workers in physical science as this bomb which overthrew with a mighty force all current and reputable theories of the constitution of Matter and its inherent quality. It was the assumption that Matter existed alone in the dense ponderable condition, which we have been told by generations of scientists is its main characteristic, that caused them to fabricate the Mechanical Theory of Nature. (550)... 

Going further even than Muir, some eminent chemists stridently opposed modem alchemy and the transmutation hypotheses emerging to explain radioactivity. Toward the end of his life, Mendeleev, for example, became quite concerned about the implications of radioactivity for his scientific and chemical world view. As Michael Gordin explains, Mendeleev s most salient exposure to radioactivity, and the genesis of most of his hostile views of the phenomenon, was his visit to the Curies laboratory in Paris in 1902. What he saw evoked similar worries as the Spiritualists had. He wrote in his Paris notebook ... [M]ust one admit whether there is spirit in matter and forces Radio-active substances, spiritualism (Gordin 2004,213). Mendeleev... 

Anon. 1911. Alchemy, Ancient and Modem. Nature 86 (May 18, 1911) 375. Anon. 1912. Radio-Activity. The Athenceum 4442 (December 14,... 

Ramsay, William, and Frederick Soddy. 1903. Experiments in Radio-Activity, and the Production of Helium from Radium. Nature (August 13, 1903) 354.—55. 

The most dangerous in their long-term effects are the tailing dumps containing radio-active waste, which are also located in the vicinity of the Dnepr bed or near smaller rivers in the Dnepr catchment basin. Many tailing dump levees and toxic radio-active waste hoarder dams are in extremely poor condition. They can be easily destroyed by natural factors (minor earthquakes, floods, rise of subterranean waters) or by man-made acts (like a terrorist act with the use of explosives), with all ensuing consequences. 

The third potentially most hazardous kind of projects is trunk pipelines. There are trunk pipelines in Ukraine that are tens, hundreds, and even thousands of kilometers long, through which hundreds of thousand and million cubic meters of oil, gas condensate, gas, ammonia, toxic chemical waste, mineral ore-dressing waste, including radio-active one, are pumped over long distances. 

The specifically labeled proteins are isolated and subjected to limited proteolytic digestion or chemical fragmentation. The highest (radio)activity fragments... 

Curie, P. and Curie, S. (1898). Sur une substance nouvelle radio-active, continue dans la pechblende. Comptes Rendus hebdomadaires des Seances de TAcademie des Sciences 127 175-178. 

Radiopharmaceuticals are prescribed according to units of radioactivity. A pharmacist practicing nuclear pharmacy may need to convert radio activity units from curies to SI unit, becquerel and its multiples, and vice versa. The following examples illustrate the interconversion of radioactive units. 

The basis of co-precipitation and adsorption methods for the purification of carrier-free radioisotopes is the use of a non-isotopic carrier for the required product. The carrier must behave chemically similar to the product in enough reactions to enable purification to be effective, its bulk being necessary for manipulation in precipitations. Its chemistry must be sufficiently different, however, to enable a simple separation of the carrier and carrier-free product to be obtained when a satisfactory purity of the radio-active material has been reached. A good example... 

Marie (NLP 1903, NLC 1911 ) and Pierre (NLP 1903 ) Curie took up further study of Becquerel s discovery. In their studies, they made use of instrumental apparatus, designed by Pierre Curie and his brother, to measure the uranium emanations based on the fact that these emanations turn air into a conductor of electricity. In 1898, they tested an ore named pitchblende from which the element uranium was extracted and found that the electric current produced by the pitchblende in their measuring instrument was much stronger than that produced by pure uranium. They then undertook the herculean task of isolating demonstrable amounts of two new radioactive elements, polonium and radium, from the pitchblende. In their publications, they first introduced the term radio-activity to describe the phenomenon originally discovered by Becquerel. After P. Curie s early death, M. Curie did recognize that radioactive decay (radioactivity) is an atomic property. Further understanding of radioactivity awaited the contributions of E. Rutherford. 

See Madame SKLODOWSKA CURIE S Radio-active Substances (2nd ed., 1904). 

Chao, Stabilization and Solidification of Hazaradous, Radio Active and Mixed Wastes, ASTM Spec. Tech. Publ., STP 1240,... 

Some precipitation methods have been applied to the separation of technetium from molybdenum when the former occurs as a radio-active daughter-product of the latter. The separation of technetium is performed by co-precipitation with tetraphenylarsonium perrhenate from an alkaline molybdate solution . In this way, also ruthenium remains in solution. Molybdate may be precipitated away from pertechnetate using 8-hydroxyquinoline " or a-benzoinoxim Pb or Ag" ions can also be used . Kuzina and Spitsyn have developed a method for concentrating technetium from ammoniacal molybdate solutions by co-precipitat-ing pertechnetate with the slightly soluble crystalline MgNH PO. ... 

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