Lerf model

After the Lerf model, Dekany et al. proposed a new model based on the diffuse reflectance infrared Fourier transform (DRIFT) measurement of GO [37-39]. The D6kdny model (Fig. 5.1) is composed of ribbons connected by cyclohexane chairs. In the ribbon region, there are functional groups such as tertiary OH, 1,3-ether, ketone, quinone, and phenol (aromatic diol). Recently, there is another GO model proposed by Rourke et al. [40], where GO is oxidative debris adhered graphitic sheets. The graphitic layer is suggested to be only slightly oxidized. 

FIGURE 13.9 Schematic of the surface functionalization of graphene oxide (a) Lerf model and (b) Dekany model. (From T. Szabo et al.. Chemistry of Materials 2006,18, 2740.)... 

MAIOLI, A., FINNICUM, D. J., KUMUAGAI, Y., IRIS simplified LERF model, ANES 2004 (Proc. Int. Conf, Miami, FL, October 3-6, 2004). 

He H, KUnowski J, Forster M, Lerf A (1998) A new structural model for graphite oxide. Chem Phys Lett 287 53-56... 

Figure 17.5 Hypothetical hybrid graphene- based on the Lerf-Klinowski model, g-CN Is type material composed of regions ranging depicted as its tri-s-triazine-based allotrope. from g-CN to graphene, including B- and N- Defect holes are included in the structures of doped graphene and GeO. The GeO region is GeO and N-doped graphene.

LERF, which is calculated with independently verified and validated complete model of probabihstic safety assessment, which represent the real and updated current state of the plant before the change and which is based on consideration of standard on PSA (ASME RA-S-2002), does not exceed significantly the value of lE-5/ry. 

A plant-specific PRA model provides quantitative results in the form of point estimates and probability distributions that postulated risk events may occur in a nuclear power plant. Two figures of merit are commonly used by the PRA analysts to demonstrate how a nuclear power plant meets the safety goals put forth by the NRC, namely the core damage frequency (CDF) and the large early release frequency (LERF). These figures of merit are applicable to all modes of operation of a nuclear power plant. For the shutdown mode, other figures of merit are equally important, such as the time to core uncovery and time to core boiling. 

FIGURE 1.6 Reduction of graphene oxide (Lerf-Klinowski model). (From Chem. Phys. Lett., 287, He, H. et al., 53, Copyright 1998, with permission from Elsevier.)... 

Particular POSs as well specific initiating events can often create asymmetries in the PSA model. The impact of this fact is important mainly for PSA application where for instance it is important to know the impact of the specific unavailabihty of a component on CDF/LERF. For this reason, the PSA model was adjusted to be symmetric, mod-ehng relevant initiating events as loop-by-loop or system-by-system events. 

The general PSA model was developed in various stages of the project. In preliminary safety analysis report, the model was based on basic design requirement and was used to evaluate the most relevant contributors to CDF and LERF. 

TEM techniques, the atomic stmcture of RGO was obtained very recently, as reported by Gomez-Navarro and co-workers. They described that the RGO sheets feature intact graphene islands of variable size between 3 and 6 nm, interspersed into defect areas dominated by clustered pentagons and heptagons. This result is in accordance to the model proposed by Lerf and co-workers, but also reveals the presence of a significant amount of topological defects for RGO. 

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