Corrosion Test Plan to Guide Canister Material Selection and Design for a Tuff Repository.

NPN-spojevi kao izvor dušika, zamjenjuju dio proteinskih komponenti obroka, a najpoznatiji NPN-spoj koji se primjenjuje u tovu junadi je urea. Urea je specifična i najviše se koristi jer je je lako dostupna i jednostavna za skladištenje, te smanjuje troškove proizvodnje. U radu se utvrđivalo dali se konzumacijom obroka s visokim udjelom Nutribos N78 u smjesi prelaze toksične granice uree, kreatinina i totalnog proteina, te su se rezultati uspoređivali s referentnim vrijednostimaNPN compounds as a source of nitrogen, replace part of protein meal components, the most famous NPN compound used in that junior is urea. Urea is specific and is most widely used because it is easily accessible and easy to store, which reduces production costs. The study found that high nutrition levels of Nutribos N78 consumed in admixture exceeded toxic limits of urea, creatinine and total protein, and compared the results with reference values

Selection of candidate container materials for the conceptual waste package design for a potential high level nuclear waste repository at Yucca Mountain

Preliminary selection criteria have been developed, peer-reviewed, and applied to a field of 41 candidate materials to choose three alloys for further consideration during the advanced conceptual design phase of waste package development for a potential high level nuclear waste repository at Yucca Mountain, Nevada. These three alloys are titanium grade 12, Alloy C-4, and Alloy 825. These selections are specific to the particular conceptual design outlined in the Site Characterization Plan. Other design concepts that may be considered in the advanced conceptual design phase may favor other materials choices

Ab initio study of the vapour-liquid critical point of a symmetrical binary fluid mixture

A microscopic approach to the investigation of the behaviour of a symmetrical binary fluid mixture in the vicinity of the vapour-liquid critical point is proposed. It is shown that the problem can be reduced to the calculation of the partition function of a 3D Ising model in an external field. For a square-well symmetrical binary mixture we calculate the parameters of the critical point as functions of the microscopic parameter r measuring the relative strength of interactions between the particles of dissimilar and similar species. The calculations are performed at intermediate ($\lambda=1.5$) and moderately long ($\lambda=2.0$) intermolecular potential ranges. The obtained results agree well with the ones of computer simulations.Comment: 14 pages, Latex2e, 5 eps-figures included, submitted to J.Phys:Cond.Ma

Comparison of measured and calculated radiation doses in granite around emplacement holes in the spent-fuel test: Climax, Nevada Test Site

Lawrence Livermore National Laboratory (LLNL) has emplaced eleven spent nuclear-reactor fuel assemblies in the Climax granite at the Nevada Test Site as part of the DOE Nevada Nuclear-Waste Storage Investigations. One of our objectives is to study radiation effects on the rock. The neutron and gamma-ray doses to the rock have been determined by MORSE-L Monte Carlo calculations and measurements using optical absorption and thermoluminescence dosimeters and metal foils. We compare the results to date. Generally, good agreement is found in the spatial and time dependence of the doses, but some of the absolute dose results appear to differ by more than the expected uncertainties. Although the agreement is judged to be adequate for radiation effects studies, suggestions for improving the precision of the calculations and measurements are made

Effect of ionizing radiation on moist air systems

The radiation chemistry of nitrogen/oxygen/water systems is reviewed. General radiolytic effects in dry nitrogen/oxygen systems are relatively well characterized. Irradiation results in the formation of steady state concentrations of ozone, nitrous oxide and nitrogen dioxide. In closed systems, the concentration observed depends on the total dose, temperature and initial gas composition. Only three studies have been published that focus on the radiation chemistry of nitrogen/oxygen/water homogeneous gas systems. Mixed phase work that is relevant to the gaseous system is also summarized. The presence of water vapor results in the formation of nitric acid and significantly changes the chemistry observed in dry air systems. Mechanistic evidence from the studies reviewed are summarized and discussed in relation to characterizing the gas phase during the containment period of a repository in tuff

Critical comments on the US Environmental Protection Agency Standards 40 CFR 191

This paper is about the US Environmental Protection Agency (EPA) ``Environmental Standards for the Disposal of Spent Nuclear Fuel, High-Level and Transuranic Wastes,`` 40 CFR 191. These standards regulate the disposal of radioactive wastes in geologic repositories. Currently, two repository sites are under investigation: The Waste Isolation Pilot Plant (WIPP) site, located near Carlsbad, New Mexico, may become the repository for defense-generated transuranic waste (TRU); and the Yucca Mountain site, located near Las Vegas, Nevada, may become the repository for spent reactor fuel and a small amount of reprocessing waste (hereinafter called high-level radioactive waste or HLW). The paper was written for readers who have an interest in 40 CFR 191 but do not have the time or inclination to ponder the technical details

Corrosion test plan to guide canister material selection and design for a tuff repository

Corrosion rates and the mode of corrosion attack form a most important basis for selection of canister materials and design of a nuclear waste package. Type 304L stainless steel was selected as the reference material for canister fabrication because of its generally excellent corrosion resistance in water, steam and air. However, 304L may be susceptible to localized and stress-assisted forms of corrosion under certain conditions. Alternative alloys are also investigated; these alloys were chosen because of their improved resistance to these forms of corrosion. The fabrication and welding processes, as well as the glass pouring operation for defense and commercial high-level wastes, may influence the susceptibility of the canister to localized and stress forms of corrosion. 12 references, 2 figures, 4 tables