Radiation products

Figure 2 Experimental and calculated background radiation production cross sections for (a) 360 g/cm plastic foil and (b) 200 fig/cm Al foil. ...

In the present systems water is subjected to radiolysis to form radiation products such as Cpq, H , OH ,... 

It is not surprising that addition of hole traps will increase the metastable yield of et (Gallivan and Hamill, 1966 Bonin et al., 1968). The yield of e( becomes sublinear at doses -1020 eV g-1, reaches a peak, and eventually decreases at very high doses. There are three possible explanations (1) reaction with radiation products (Eckstrom et al., 1970) (2) electron tunneling to radiation-produced scavengers (Miller, 1972) and (3) dielectron formation (Feng et al., 1973). 

When the HCN contained 1-2 % mole of water the yields tended to increase exponentially with dose. This was due to the occurrence of a superimposed thermal reaction, which became faster as the radiation products accumulated and persisted after irradiation ceased. Hummel and Janssen attributed it to the hydrolysis of imino and cyano groups on the polymer chain. They suggested that the ammonia generated in this process reacted with HCN to form cyanide ions, which then initiated the polymerisation. 

Pulse radiolysis, using as time-resolved detection methods optical absorption, luminescence, electrical conductivity or electron spin resonance can be expected to give information on the formation of transient or permanent radiation products and on their movement. 

Studies on medical devices that do not come in contact with or are not implanted in humans Tests of diagnostic products Chemical and physical tests of radiation products Tests conducted for the release of licensed biological products... 

Table II. Radiation Products Induced in Fatty Acid Esters and Triglycerides...

The study of the radiation products induced in methyl oleate, methyl stearate, trioleate, and tristearin also supports the argument for direct bond cleavage. Data are given in Table II, and a representation of the process is indicated below. 

Wetmore SD, Boyd RJ, Erikson LA (1998b) Radiation products of thymine, 1-methylthymineand uracil investigated by Density Functional Theory. J Phys Chem B 102 5369-5377 White B, Smyth MR, Stuart JD, Rusling JF (2003) Oscillating formation of 8-oxoguanine during DNA oxidation. J Am Chem Soc 125 6604-6605... 

Japan, and South America, and commercial amounts of wood-plastic flooring were produced for airport terminals and office buildings. Today there is no known commercial gamma radiation production of wood-plastics outside of the United States. 

Among numerous previous studies on the reaction mechanism, Geuskens et al. [31] proposed the most detailed mechanism based on the analysis of radiation products as well as the effect of added ethylmercaptan ... 

HST observations in the UV of a broad band roughly consistent with the Hartley band, suggest the presence of O3 in the surface of Ganymede. The possible presence of O3 is important, since O3 is not a direct radiation product of ice, but forms readily in Therefore, its presence reen-... 

Pyrimidine and purine radiation products close agreement between experiment and theory... 

The previous sections have discussed the effects of radiation on individual DNA components in relation to experimental results obtained from single crystals of base derivatives at low temperatures. Issues can now be addressed which question the relevance of these studies to the identification of the radiation products in full DNA. Early ESR work on DNA revealed that the classification of radiation products is a difficult task since many of the DNA radicals are extremely similar and, therefore, the hyperfine couplings and g-factors are not sufficient to separate their spectra. The implementation of a variety of experimental conditions allows for the determination of the dependence of... 

The radiation products generated in DNA will be discussed in the next two sections in terms of how the primary cation and anion radicals decay to form secondary radical products. This discussion will encompass results from single crystals [15], the aqueous state [92,101], the calculations presented in Section 2, as weU as those obtained from ab initio studies [72], and studies on oriented and randomly oriented DNA [76,78],... 

Radio- Half-life Decay Principal radiation Production Usage... 

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