Although there are several theoretical predictions of the dependence of the G-value on X-ray energy, measurements have not been made below approximately equal to 7 keV. Using a ferrous sulfate solution modified by the addition of benzoic acid, we have measured the relative G-values for Alk characteristic X-rays (1.5 keV), 238Pu alpha-particles (3.7 MeV), 60Co (1.17 MeV) and 137Cs (0.66 MeV) gamma-rays. This modified ferrous sulfate solution gave a 4-fold increase in sensitivity relative to the conventional solution, making measurements with the Alk X-rays feasible. The relative ferrous-to-ferric conversions as a function of dose were similar for the two gamma-ray energies, yielding G-values of 1.62 and 1.59 mumol J-1 for the 60Co and 137Cs radiations, respectively. The alpha-particle G-value was 0.52 mumol J-1, or 31 per cent of that for the 60Co gamma-rays, in good agreement with previous measurements. The Alk X-rays had a G-value of 0.92 mumol J-1 or 57 per cent of that of the 60Co radiation. This G-value for the 1.5 keV X-rays is within 20 per cent of the values predicted by current theories, and theoretical values are within the error range of our measurement. The consistency between the experimental value reported here and theoretical G-values for ultrasoft X-rays should be valuable for models of radiation action on biological systems.
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Ind Eng Chem Res
December 2023
Chemical Engineering and Applied Chemistry (CEAC), Energy & Bioproducts Research Institute (EBRI), Aston University, Birmingham B4 7ET, U.K.
Despite offering low-carbon and reliable energy, the utilization of nuclear energy is declining globally due to high upfront capital costs and longer returns on investments. Nuclear cogeneration of valuable chemicals from waste biomass-derived feedstocks could have beneficial impacts while harnessing the underutilized resource of ionizing energy. Here, we demonstrate selective methanol or acetaldehyde production from ethylene glycol, a feedstock derived from glycerol, a byproduct of biodiesel, using irradiations from a nuclear fission reactor.
View Article and Find Full Text PDFPhys Chem Chem Phys
November 2023
Notre Dame Radiation Laboratory, University of Notre Dame, Notre Dame, IN 46556, USA.
The radiation- and chemically-induced radicals from tributyl phosphate (TBP) have been characterized by EPR spectroscopy and theoretical calculations. The yield of X-ray-generated TBP radicals measured by a PBN spin trap is 0.22 μmol J (2.
View Article and Find Full Text PDFZhongguo Zhong Yao Za Zhi
September 2022
School of Chinese Materia Medica, Beijing University of Chinese Medicine Beijing 102488, China.
The present study investigated the chemical constituents from Uncaria sessilifructus and their neuroprotective activities. The compounds were separated and purified from the 90% ethanol extract of U. sessilifructus by various chromatographic methods, including silica gel, Sephadex LH-20, and semi-preparative HPLC.
View Article and Find Full Text PDFWater Res
June 2022
State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China. Electronic address:
Flow-electrode capacitive deionization (FCDI) is viewed as a potential alternative to the current state-of-the-art electrodriven technology for the desalination of brackish water. However, the key shortcoming of the FCDI is still the discontinuous nature of the electrode conductive network, resulting in low electron transport efficiency and ion adsorption capacity. Here, a novel magnetic field-assisted FCDI system (termed magnetic FCDI) is proposed to enhance brackish water desalination, simply by using magnetic activated carbon (MAC) as flow electrodes.
View Article and Find Full Text PDFEnviron Sci Technol
October 2021
State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China.
The stack configuration in flow-electrode capacitive deionization (FCDI) has been verified to be an attractive and feasible strategy for scaling up the desalination process. However, challenges still exist when attempting to simultaneously improve the desalination scale and the cell configuration. Here, we describe a novel stack FCDI configuration (termed a gradient FCDI system) based on a membrane-current collector assembly, in which the charge neutralization enables the in situ regeneration of the flow electrodes in the single cycle operation, thereby realizing a considerable increase in the desalinating performance.
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