Ionizing radiation sulfate

Cooling, sensation based on generalized membrane response, 15-18 Copper sulfate, use for control of off-flavor metabolites, 327 Cysticercus species, ionizing radiation, 296,298f... 

HPhe Fricke dosimeter (ferrous sulfate solutions) has been used to measure A the radiation intensity of various types of ionizing radiation sources since its development by Fricke and Morse in 1927 (2). It is widely accepted because it yields accurate and reproducible results with a minimum of care. This system meets many of the requirements specified for an ideal dosimeter (5, 9) however, it has a limited dose range, and for our applications it has been necessary to develop a dosimeter covering larger doses. Of the systems reviewed (6, 7), two (ferrous sulfate-cupric sulfate and ceric sulfate) showed the most promise for use with the radiation sources at the U. S. Army Natick Laboratories (8). Of these, the ferrous-cupric system has received the most use, and this paper describes our experience in using this system and suggests procedures by which it may be used by others with equal success. 

Mohan Rao, P.K. Biological effects of combination treatments with ionizing radiation (X-rays) and diethyl sulfate (dES) in barley. Mutat. Res. 16 322-327, 1972. 

For quantitative studies in radiation chemistry, it is essential that the energy input into the irradiated volume should be accurately determined. For this purpose, the most versatile and reliable method is the ferrous sulfate dosimeter, proposed by Fricke and Morse. The method involves the use of an air-saturated solution of 10 M ferrous sulfate and 10 M sodium chloride in 0.8 N sulfuric acid. On exposure of the solution to ionizing radiations, the ferrous ion is oxidized to ferric ion, which may conveniently be determined accurately by spectrophotometry. The amount of chemical change is proportional to the total energy-input, independent of dose rate, and (within wide limits) independent of the concentration of ferrous ion, ferric ion, and oxygen. The main reactions involved are as follows. 

The effect of other inorganic radicals on the nucleobases, apart from the water radicals mentioned above, has repeatedly been studied, for instance the sulfate radical which has been used to generate nucleobase radical cations with the aim to mimic the direct effect of ionizing radiation on DNA. Carbon-centred... 

Nuclear oxidative phosphorylation is difficult to quantify. Although oxygen uptake in the nucleus can be measured, no exact P/O ratio is available. This is because only the AMP already present in the nuclear preparation can be converted to ATP any AMP added to the nuclei remains unaltered. An intriguing observation is the effect of DNase on the phosphorylation of AMP. (Allfrey has proposed that DNase blocks ATP synthesis in the nucleus indirectly namely, by inhibition of the nuclei by the histones, which after DNA extraction are no longer associated with DNA by salt linkages [35].) The enzymic extraction of 55% of the DNA in the nucleus leads to the loss of nuclear phosphorylation properties, which can be restored by adding DNA to the system. The effect of DNA is not specific because DNA can be replaced by RNA, polyadenylic acid, heparin, chondroitin sulfate, and polyethylene sulfate. Oxidative phosphorylation in thymus nuclear preparation has been confirmed in two laboratories. Whole body doses of ionizing radiation inhibited oxidative phosphorylation in thymus nuclei. 

Suspension Polymerization, in this technique, liquid VF is suspended in water with the help of a dispersion stabilizer (70). Polymerization is initiated by an organic peroxide such as diisopropyl peroxydicarbonate below the critical temperature of VF (71,72). The reaction can also be initiated by uv light and ionizing radiation (64,73). VF dispersions are usually stabilized by water-soluble polymers such as cellulose derivatives, eg cellulose ester and sodium carboxymethylcellu-lose, and poly(vinyl alcohol). Inorganic salts such as magnesium carbonate, barium sulfate, and alkylsulfoacids are also used. 

Introduction. The decision to use type-347 stainless steel as the major material of construction and a uranyl sulfate solution as the fuel for HRE-1 and HRE-2 was based, at least in part, on the demonstrated compatibility of the two components and on the fact that the technology of the austenitic stainless steels was well developed. Articles 5-4.2 through 5-4.7 present the results of an extensive investigation of the corrosion of type-347 stainless steel in uranyl sulfate solutions in the absence of ionizing radiation, and in Article 5-4.8 the effect of ionizing radiation on the corrosion of stainless steel is discussed. Further details are reported in the HRP quarterly progress reports [28]. 

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