Gamma radiation induces hydrogen absorption by copper in water

Abstract

One of the most intricate issues of nuclear power is the long-term safety of repositories for radioactive waste. These repositories can have an impact on future generations for a period of time orders of magnitude longer than any known civilization. Several countries have considered copper as an outer corrosion barrier for canisters containing spent nuclear fuel. Among the many processes that must be considered in the safety assessments, radiation induced processes constitute a key-component. Here we show that copper metal immersed in water uptakes considerable amounts of hydrogen when exposed to γ-radiation. Additionally we show that the amount of hydrogen absorbed by copper depends on the total dose of radiation. At a dose of 69 kGy the uptake of hydrogen by metallic copper is 7 orders of magnitude higher than when the absorption is driven by H2(g) at a pressure of 1 atm in a non-irradiated dry system. Moreover, irradiation of copper in water causes corrosion of the metal and the formation of a variety of surface cavities, nanoparticle deposits, and islands of needle-shaped crystals. Hence, radiation enhanced uptake of hydrogen by spent nuclear fuel encapsulating materials should be taken into account in the safety assessments of nuclear waste repositories.

Hydrogen effects on mechanical performance of nodular cast iron

“…( , , ) = sin ( ) (10) In the DIC Challenge paper, the spatial resolution is characterized by the wavelength of the sinusoidally varying displacement field for which the measured displacement variation amplitude or strain variation amplitude reaches an arbitrarily chosen attenuation threshold. The attenuation ratio R for both displacements and strains equals to the exponential in equation (10):…”

“…The ultimate tensile strength is also drastically reduced from >300 MPa to <270 MPa. In addition to reduction in strength, CERT under continuous hydrogen charging shows a remarkable reduction of elongation to fracture from [9][10][11][12][13] These values may be compared to the requirement of 240 MPa for yield strength, 370 MPa for ultimate tensile strength, and 12 % for elongation to fracture of the cast iron [3]. The ultimate tensile strength of the studied cast iron tested in air and distilled water does not meet the requirement most likely due to the thin plate shape of the tensile specimens.…”

“…As a matter of fact, hydrogen uptake is currently one of the uncertainties mentioned by the Swedish Nuclear Safety Authority (SSM) [8], which has not been studied extensively enough to rule it out as a possible threat to canister integrity. Some hydrogen generation will occur in corrosion reactions outside of the canisters [9] and in hydrolysis of remnant water from the fuel elements [10] inside the canisters. In addition, hydrogen absorption may result from neutron radiation, since neutron radiation decays into protons (p + =H + ) and electrons (e -).…”

Prebiotic Geochemical Automata at the Intersection of Radiolytic Chemistry, Physical Complexity, and Systems Biology

“…A water molecule can respond in a number of different ways (Figure 4(b)), but most of these responses involve entering an excited state (H 2 O * ) or the ejection of an electron (e − ), leaving behind a water radical (H 2 O •+ ) [71]. This process occurs very rapidly, on the order of 10 −16 seconds, much shorter than the duration of typical molecule-molecule collision frequencies.…”

Investigation of the effects of gamma radiation on plasma levels of Zn, Cu, Mn and Se in nuclear medicine staff

“…Gamma radiation is a common type of radiation that can split water and lead to the formation of reactive oxygen species (ROS) (Lousada et al, 2016;Zheng et al, 2017), which in turn cause oxidative stress and cell death. Since ROS such as hydroxyl radicals (OH • ) and superoxide anion (O 2 • ) have unpaired electron in their structure, they can interact with DNA, proteins and lipids, leading to oxidative damages and cells death (Zheng et al, 2016;Chuenpee et al, 2017).…”