Hydrogen (H2) is produced in geological settings by dissociation of water due to radiation from radioactive decay of naturally occurring uranium ((238)U, (235)U), thorium ((232)Th) and potassium ((40)K). To quantify the potential significance of radiolytic H2 as an electron donor for microbes within the South Pacific subseafloor basaltic aquifer, we use radionuclide concentrations of 43 basalt ...

Purpose: To investigate conflicting results demonstrating higher cell-kill by irradiated high atomic number (Z) material, gold (Au) in tumor compared to Monte Carlo (MC) modeled enhancement in radiation dose deposition, and to compare the difference between radiosensitizing effects of gold and platinum. Methods and Materials: Since a majority of cell kill due to radiation is mediated by free ra...

Abstract Sulfur is the tenth most abundant element in universe and known to play a significant role biological systems. Accordingly, recent years there has been increased interest of sulfur astrochemical reactions planetary geology geochemistry. Among many avenues research currently being explored laboratory processing astrophysical ice analogues. Such involves synthesis an specific morphology ...

Context. Carbonaceous chondrites have undergone alteration in their parent bodies and display oxidized secondary phases, including sulfates CI CM chondrites. The cause of the formation these is yet to be determined. Aims. This study investigates potential endogenous radiolysis water (i.e., caused by radionuclides present rock) on carbonaceous Radiolysis may contributed enhanced degree oxidation...

Nanoporous gold was used as a high specific surface material to describe the water radiolysis in the vicinity of metal surfaces. Porous gold monoliths were prepared by electrolytic dissolution of silver in Au-Ag alloys and characterized by small angle neutron scattering. The hydroxyl radical production under gamma irradiation was measured by benzoate scavenging in water confined in 50 nm porous...

By assuming that HO2 ● radical production in water and H2 production in benzene are 2 hit processes, and applying the concepts of track physics, we are able to obtain a parametric fit to the yields of these reactions by heavy ion radiolysis from knowledge of the radial dose distribution about a heavy ion’s path. We make no use of the concept of a track core, for no clearly definable track core ...

The dependence of Gi(-M) values of histidine on the concentration of irradiated 10(-4) - 10(-1)M solutions, pH and the presence of O2, N2O and sec-butyl alcohol was investigated. In oxygen-free medium the maximum radiation sensitivity of histidine was found at pH 5--8; in oxygenated solutions it was shifted to the 6--1 pH range. The formation of radiation products was also studied. The course o...

In the study, heterogeneous radiolysis of water in adsorption and liquid form was studied (RaO)x(SiO2)y+H2O system. The effect radioactivity radium cations process temperature on release molecular hydrogen determined (T=300‒673K). mechanism with participation system has been proposed.