Radioactivity studied

The modern theory of the electronic structure of the atom is based on experimental observations of the interaction of electricity with matter, studies of electron beams (cathode rays), studies of radioactivity, studies of the distribution of the energy emitted by hot solids, and studies of the wavelengths of light emitted by incandescent gases. A complete discussion of the experimental evidence for the modern theory of atomic structure is beyond the scope of this book. In this chapter only the results of the theoretical treatment will be described, These results will have to be memorized as rules of the game, but they will be used so extensively throughout the general chemistry course that the notation used will soon become familiar. 

Bowen VT, Strohal P, Saiki M et al. (1970) In Reference Methods for Marine Radioactivity Studies (eds) Nishiwaki Y, Fukai R, International Atomic Energy Agency, Vienna, Austria, p. 12... 

Aakrog A (1975) Reference methods of marine radioactivity studies II. Technical report services no. 169. IAEA, Vienna, Austria... 

Folsom T.R., Sreekumaran C. Some reference methods for determining radioactive and natural ceasium for marine studies. Technical reports series No.118. Reference methods for marine radioactivity studies. IAEA, Vienna (1970)... 

The Achilles Heel In the use of stable Isotopes for human nutritional studies Is the methodology available for the detection of the enriched stable Isotope Unlike the radioactive studies where one can use a relatively cheap and very accessible technique such as scintillation counting, there appear to be only two methods for the analysis of metal Isotopes mass spectrometry (10-18) and neutron activation analysis (7-9) To date, both methods have proven to be less than desirable because of the time-Intensive nature of the analysis ... 

Baxter, M.S., et al.. Marine radioactivity studies in the vicinity of sites with potential radionuclides releases IAEA-SM-339/131, p. 167, IAEA, Vienna, 1996. 

Optimize Conditions for the Radiochemical Separation of Plutonium from Large Volume Seawater Samples, in Reference Methods for Marine Radioactivity Studies II. Ruthenium, Silver, Iodine, Zirconium, and the Transuranic Elements, IAEA Tech, Rep, Ser, (1975) 169, 69. 

Folsom, T. R., Sreekuman, C., "Reference Methods for Marine Radioactivity Studies, IAEA Bull (1970). 

Many of the chromatographic procedures are applicable to the measurement of labeled hydroxyproline in general they do not allow for multiple simultaneous determinations. Since collagen hydroxyproline is labeled only by administering its precursor, proline, in labeled form, the difficulties in radioactive studies have arisen largely because the nonhydroxy-proline metabolic products of proline or proline itself have not been rigorously separated from hydroxyproline or hydroxyproline-derived pyrrole. This is the purpose of the more recently introduced modifications for labeled hydroxyproline assay (Jll, L12). It is too early to know whether one or both of these will suffice for general use. 

Radioactive studies in which solvent-extractable (14C) was characterized by chromatographic assay have revealed no lag-phase when low concentrations <10 ppm) of (14C)2,4-D and (14C)2,4,5-T were incubated with moist soils (18-21). Degradation of several phenoxyalkanoic acids at soil concentrations of <5 ppm using... 

Recently, accelerated mass spectrometry (AMS) have been used in mass balance studies in animals and humans (Garner et al., 2002 Mauthe et al., 1998 Rickert et al., 2005). AMS only requires a small amount of radioactivity (nCi) with a normal dose (not considered as a radioactive study in some countries). However, this technique has limited applications in metabolite identification by connecting LC/MS/MS analysis and radioactivity detection. 

Later, as we recognized phenomena which could not be treated and explained using only total or bulk deposition data, we developed an instrument which quantitatively and automatically collects separate wet and dry fractions of atmospheric deposition.The instrument is shown in Fig. 2. The onset of precipitation is sensed by the sensors mounted on both sides of the roof, causing it to move off the "wet bucket" and cover the "dry". The wet/dry deposition collectors have so far been used on a rather limited basis in radioactivity studies to carry out specific experiments. 

The discoveries of helium and radon stand out as unusual. Radon was discovered as a result of radioactivity studies, or, more precisely, owing to the application of the radiometric method. Therefore, we shall deal with it in Chapter 11, which is devoted to the history of radioactive elements. The discovery of helium occupies an exceptional place in the history of chemistry. In 1868 a line was detected in the spectra of solar prominences, which could he assigned to none of the elements known on the earth. This line was attributed to a new element on the sun which was called helium . Twenty seven years later helium was first extracted on Earth. 

Such exclusive situation soon became a rule. Therefore, we shall have to discuss briefly some important events in the history of radioactivity studies. Now we must finish the story of radon. This name remained because radon is the longest-lived element among the radioactive inert gases. Ramsay suggested to name it niton (from the Latin for glowing) but this name did not take root. 

Leblond and his associates also proposed that the Golgi apparatus is the major center for the last step of glycoprotein biosynthesis—namely, the addition of the sugar to the polypeptide moiety. Biochemists have shown that the sugar molecules are inserted in glycoprotein only when the biosynthesis of the polypeptide chain has been completed. Histochemical and radioactive studies have suggested that the proportion of sugar increases within the protein molecules that concentrate... 

Holm, E. Fukai, R. (1977). Method for multi-element alpha spectrometry of actinides and its application to environmental radioactivity studies. Talanta, 24, 659-64. 

International Atomic Energy Agency. 1970b. Reference Methods for Marine Radioactivity Studies. 

That tryptophan serves as the dietary precursor of serotonin has been adequately demonstrated both by radioactive studies in animals (Udenfriend et al., 1956) and by balance studies in patients with malignant carcinoid (Sjoerdsma et al., 1956). In the latter case as much as 60% of the... 

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