Low dose zone

International Dose Response Society, Focusing on the dose-response in the low-dose zone (2014). Available at http //dose-response.org (accessed December 2015). 

Direct measurement of riboflavin, FMN, and FAD in plasma or erythrocytes may be made by HPLC, usually with fluorescence detection after protein precipitation or by capillary zone electrophoresis with laser-induced fluorescence detection (CZE-LIF). In a study of riboflavin status and FMN and FAD concentrations in plasma and erythrocytes from elderly subjects at baseline and after low-dose riboflavin supplementation, using both activation coefficient measurements and CE-LIF, it was concluded that concentrations of aU Ba vitamers except plasma FAD are potential... 

Chemical interactions can be accounted for. While threshold dose response model can only deal with chemical interactions for responses that exceed a threshold, the hormetic model also does this. These models differ where the interaction occurs in the hormetic stimulatory zone. In the case of the hormetic chemical interactions, the maximum response is still constrained to 30-60% above the control value a characteristic that the threshold and linear at low-dose models do not have. 

Fig. 6. Hydrogen production from irradiated hydrogenated nitrile-butadiene rubber (HNBR) with additives The low doses curve shows incubation zone of hydrogen production caused by the reach of primary radiolysis products with additives.

Population data are site specific and will be presented at the time of application for a specific site. However, for purposes of estimating population doses, a population density is assumed to average 500 persons per square mile over a radial distance out to 30 miles. A bounding low population zone of 425 meters (i.e. coincident with the exclusion area boundary) has been selected for purposes of safety analyses. 

A program of onsite data collection, supplemented by National Weather Service (NOAA) summaries from locations near a specific site, will be conducted. Information from the onsite program will be used to confirm that the limiting offsite dose analyses and annual average X/Q values are adequate relative to exclusion area boundary radius and low population zone requirements. 

The numerical dose values given in lOCFRlOO for determining the extent of the exclusion area and low population zone (LPZ) are consistent with all of the selection bases and have been applied, without modification, to the licensing of the FSV-HTGR plant. Therefore, these dose values have been included as top-level regulatory criteria. 

Two-hour exclusion area boundary and 30-day low population zone accident doses less than 25 rem whole body and 300 rem thyroid. 

Dose limits equal to the preeeding ones for the whole aeddent duration at the external border of the low population zone. 

Figure 4b presents the concentration dependence of the order parameter for IM-DPhO. In this case we have obtained the bimodal curve with two maximum at 10 and 10 mol/l, where the effect is the same, and co-called dead zone at 5 x 10 -5 x 10 mol/1, within the effect equals to zero. It should be noticed that a polymodal type of dose-effect dependences has been observed for a number of biological active substances effective at ultra-low concentrations [27]. Usually, the bimodal curve is characterized by second maximiun at the effective ultra-low doses - less than 10 "-10 mold [28], In our experiments the second maximiun of parameter S observed at 10 mol/1 IM-DPhO, but as mentioned above the effective concentration of substances in the membranes is in 100 times less than added ones. Thus, the second maximum observed at 10 " mol/1 of IM-DPhO and it can be regarded as substances effective at Ihe ultra-low concentrations. 

The mechanism of the loss of uniform elongation of V-alloys at relatively low temperature (<400°C) and low dose ( 0.1 dpa) has been investigated. Microstruc-tural observation after tensile tests of the irradiated samples showed that radiation-induced defect clusters were lost in layer structures and the defect-free zones were accompanied by dislocation channels [38]. Fig. 11.13 shows the layer stmctures... 

CFR 100 stipulates that neither an individual located at any point on the outer boundary of the exclusion area for two hours immediately following onset of the postulated fission product release nor an individual located at any point on the outer boundary of the low population zone for the duration of the accident should receive a total radiation dose in excess of 25 rem to the whole body or 300 rem to the thyroid. Thus, the design-basis LOCA, whose consequences were not to be exceeded by any other credible accident, became the focus of siting evaluations. 10 CFR 100 also stipulates that the... 

The potential doses at the exclusion area boundary and the low population zone are calculated assuming that the accident occurs when the meteorological conditions are worse (from the standpoint of the calculated doses) than those that would be expected to prevail at the site approximately 95% of the time [Regulatory Guides 1.3 and 1.4]. Table 2.1-4 presents the results from typical calculations of potential offsite doses due to several kinds of design basis accidents. Even with the considerable number of pessimistic assumption employed, the calculated doses that a person out-of-doors in the vicinity of the plant might receive for the entire course of the accident are usually well below the 10 CFR Part 100 guidelines. 

Doses are calculated for a hypothetical person standing outside in the radioactive plume, for 2 hours at the exclusion area boundary and during the entire period of plume passage at the low population zone outer boundary. [10 CFR 100 (d)]... 

Figure 6 Low-dose, 200 kV HREM image of DCHD in the [010] zone showing (200), (101), and (-101) fringes.

Models for transport distinguish between the unsaturated zone and the saturated zone, that below the water table. There the underground water moves slowly through the sod or rock according to porosity and gradient, or the extent of fractures. A retardation effect slows the motion of contaminant by large factors in the case of heavy metals. For low level waste, a variety of dose calculations are made for direct and indirect human body uptake of water. Performance assessment methodology is described in Reference 22. 

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