Reactor radiation

Avrami W.E. Voreck, A Determination of Reactor-Radiation-Resistant Explosives, Propellants, and Related Materials , PATR 3782 (Nov 1959), 126, AD-506895 22) E.R. Ward... 

Vulpis (1973) added pure natural boron as H3B03, which contains about 19% B-10, to the blood culture. It was then irradiated with thermal neutrons from a reactor. The reaction of B-10(n,a)Li-7 within the culture served as alpha source. The dose range was 35 to 195 mGy according to her dose estimation which was complicated by subtracting the dose due to the reactor radiation alone. The dicentric chromosomes appeared to follow a linear response up to about 0.18 Gy and then leveled off to a plateau due to a "saturation effect. The relative biological efficiency (RBE) with respect to X-rays with the doses up to 5f1 Gy was found to be 23. v... 

Harteck P, Dondes S (1956) Producing chemicals with reactor radiations. Nucleonics 14 22-25... 

The radiation - induced changes noted are in weight loss, gas evolution, mechanical sensitivity, thermal sensitivity and stability, and ex pi performance. The effects will be described with the type of nuclear radiation used. The format describes the radiation effects on expls, propints and pyrots with the sequence of radiations utilized (when applicable) as follows, a - particles, neutrons, fission products, reactor radiation (fast and slo w neutrons plus gammas), gammas (7), underground testing (UGT), X-rays, electrons, and other nuclear radiations... 

Reactor Radiation. Gh, for Ca(N03 )2 solutions from O.OlAf to l.OAf is quantitatively expressed for reactor radiation by Equation 12. 

A different model to explain the variations in Gh, with LET is induced here. The failure of Equations 2-6 for Co60 7-radiation, Equation 12 for reactor radiation, and Equation 13 for 18.9 m.e. v. D + to represent quantitatively the dependence of Gh, on solute concentrations less than 0.01M is interpreted as evidence that H2 formation for these radiations results from two reactions intraspur and interspur reactions. In interspur reactions, intermediates from one spur react with intermediates from an adjacent spur before they escape into the bulk of the solution. 

There is excellent agreement between the three values for thjo - s,h2o obtained for NO - with Co60 7-radiation and reactor radiation,... 

Some of the data used to obtain Equations 1-14 is shown in Figure 7. x is a normalized factor for solute concentration and is equal to a ratio of constants obtained from Table II. The correlation for fission recoils and 7-radiation is very good over the entire concentration range. The curves in Figure 7 are theoretical and represent Equation 8 for fission recoils, Equation 12 for reactor radiation, Equation 13 for 18.9 m.e.v. D+, and Equation 3 for 7-radiation. Figure 7 emphasizes that the... 

Bands initially present in unirradiated PE Bands induced due to y radiation Bands induced due to reactor radiation Literature Intensity change on y radiation Low y dose Middle y dose Highy dose... 

Early work in this field was conducted prior to the availability of powerful radiation sources. In 1929, E. B. Newton "vulcanized" rubber sheets with cathode-rays (16). Several studies were carried out during and immediately after world war II in order to determine the damage caused by radiation to insulators and other plastic materials intended for use in radiation fields (17, 18, 19). M. Dole reported research carried out by Rose on the effect of reactor radiation on thin films of polyethylene irradiated either in air or under vacuum (20). However, worldwide interest in the radiation chemistry of polymers arose after Arthur Charlesby showed in 1952 that polyethylene was converted by irradiation into a non-soluble and non-melting cross-linked material (21). It should be emphasized, that in 1952, the only cross-linking process practiced in industry was the "vulcanization" of rubber. The fact that polyethylene, a paraffinic (and therefore by definition a chemically "inert") polymer could react under simple irradiation and become converted into a new material with improved properties looked like a "miracle" to many outsiders and even to experts in the art. More miracles were therefore expected from radiation sources which were hastily acquired by industry in the 1950 s. 

McDaniel, R.H., The Effects of Reactor Radiation on Three High-Temperature Solid-Film Lubricants, Lubric. Eng., 21, 463, (1965). 

Silica gel evacuated at 500 to 600° is a poor exchange catalyst, typical experiments showing half-times at room temperature of hundreds of hours for a gram of catalyst in 50 cm of gas. Reasonable doses of radiation (10 ° to 10 i ev/gm of y-rays or reactor radiation) produce a catalyst so active it can be tested at —196°, where the half-time may be less than 5 minutes (69, 83). The main features of this extraordinary sensitivity have been amply confirmed by Boreskov et al. (68, 70, 83) and by Kohn and Taylor (69, 82) they are summarized for reference before a consideration of possible mechanisms. 

Heavy-particle radiation would be expected to increase the catalytic activity simply because it always produces ionization as well as displacement. In the case of silica gel and silica-alumina, reactor radiation produced large increases in activity (82), but the uncertainties of the dosimetry and of the temperature corrections to the rates make it unwise to speculate on the relative efficiencies of fast neutrons and y-rays. 

All the forms of silica and silica-alumina studied are similar in the rates at which catalytic activity was induced in them by radiation (82). For instance, the yields of increased activity per unit dose were within a factor of about 100 of each other for silica gel, quartz, vitreous silica, cristobalite, and Cab-o-sil, although before irradiation the quartz and vitreous silica were lO to 10 times as active as any of the gels. In a series of experiments using reactor radiation in which silica gel was compared with silica-aluminas, the yield differed by less than a factor of 100. In other experiments the differences have been even less (83). These results are consistent with a single kind of defect being introduced at... 

Two rather different studies have been reported, one by Schwab and Konrad 110), using reactor radiation and 0-alumina, and the other by Acres, Eley, and Trillo (106), using y-raysand a-alumina. Since the latter material behaved toward hydrogen-deuterium exchange similarly to y-alumina, it is likely that the surface layer was in the y-modification, as found by electron diffraction in another case (84). 

Although Muraour and Ertaud confirmed the results of Bowden and Singh [37,38], a different environment was used. The former utilized reactor radiation at higher dose rates and doses compared to the slow thermal neutron radiation of the latter. For example, the thermal neutron dose rate for lead azide was 4.2 X 10 compared to 2 X 10 n/cm /sec and the total dose was 3 X lO " compared to 7.2 X lO n/cm. ... 

ROBERT c. LIVINGSTON, Reactor Radiation Division, National Bureau of Standards, Washington, D.C. 

Among the first expts in which the effect of pulsed reactor radiation was attempted on any proplnt was the KIWI—TNT transient excursion test in the NERVA program (Refs 159 192). 

Salaices M., 2002, Photocatalysis in Slimy Reactors Radiation, Transmission and Kinetic Modeling. PhD Dissertation, University of Western Ontario. 

Romero, R. L., Alfano, O. M., Cassano, A. E., 1997, Cylindrical photocatalytic reactors. Radiation absorption and scattering effects produced by suspended fine particles in an annular space. Ind. Eng. Chem. Res., 36 3094-3109. 

Reactor model. The reactor model was constructed according to the following sequence (i) the annular reactor, radiation distribution model of Romero etal. (1983) was adapted for this particular set-up (ii) the tubular lamp with voluminal and isotropic radiation emission model was applied to this system (iii) a mass balance for an actinometric reaction carried out in a tubular reactor inside the loop of a recycling system was adapted from Martin etal. (1996) and (iv) the verification of the radiation model, actinometer experiments were performed in the reactor to compare theoretical predictions... 

A primary objective of this work is to provide the general theoretical foundation for different perturbation theory applications in all types of nuclear systems. Consequently, general notations have been used without reference to any specific mathematical description of the transport equation used for numerical calculations. The formulation has been restricted to time-independent and linear problems. Throughout the work we describe the scope of past, and discuss the possibility for future applications of perturbation theory techniques for the analysis, design and optimization of fission reactors, fusion reactors, radiation shields, and other deep-penetration problems. This review concentrates on developments subsequent to Lewins review (7) published in 1968. The literature search covers the period ending Fall 1974. 

The reactor radiation instruments are listed in Table 5.2.A. It will be noticed that with one - exception these instruments are located in the reactor. The one. exception, the water monitor chambers, can reasonably be included with the reactor instruments since they monitor water samples from the 37 sampling tubes distributed across the bottom of the active lattice. 

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