Properties of radicals created by γ—ray irradiation of silk

The propoerties of radicals fromγ-ray irradiated silk fabrics were studied by electron spin resonance method(ESR).The ESR spectra of silk fabrics irradiated in N2 showed a doublet at room temperature,The doublet became a singlet at g=2.0057 after placing the sample in air for 24 hours.This can be explained by formation of peroxide radicals.The radical concentration of the irradiated silk fabric and the decay rate of radicals are significantly affected by irradiation conditions.which include the absorbed dose.atmosphere,and water content of the silk fabric samples.However,no dose rate effect on the radical concentration was observed.The results are of help in our practice of property modification of silk products by radiation graft copolymerization.     

Satellite-based detection of 16.76 MeV γ-ray from H-bomb D-T fusion

Based on the high energy γ-ray yield from the H-bomb D-T fusion reaction,it brings forward the idea applying the 16.76 MeV γ-ray to judge whether the H-bomb happens or not,and to deduce the explosion TNT equivalent accurately.The Monte Carlo N-Particle was applied to simulate the high energy γ-ray radiation characteristics reaching the geosynchronous orbit satellite,and the CVD diamond detector suit for the requirements was researched.A series of experiments were carried out to testify the capabilities of the diamond detector.It provides a brand-new approach to satellite-based nuclear explosion detection.     

Effect of Concentration of DNA in DNA Damage Induced by γ-ray

DNA is considered to be the most important bio-macromolecule and target molecule responsible for all biological effects. Many kinds of damage can be induced by radiation, such as base damage, single strand break （SSB）, double strand break （DSB） and crosslink of DNA and protein. In irradiation, the concentration of DNA may be an important parameter influencing DNA damage.     

Effect of Dose Rate in DNA Damage Induced by γ-ray

DNA is considered to be the most important bio-macromolecule and target molecule responsible for all biological effects. Many kinds of damage can be induced by radiation, such as base damage, single strand break （SSB）, double strand break （DSB） and crosslink of DNA and protein. In irradiation, dose rate is also an important parameter influencing DNA damage.     

Preparation of copper nano-particle powder by γ-irradiation

Copper nano-particles were prepared by 100 kGy room temperature γ-ray irradiation of CuSO4 aqueous solution added with surfactant and inactive agent.Effects of the surfactants and pH value on particle size and morphology of the Cu powder,and the storage stability,were investigated.Structure,morphology,particle size and melting point of the copper nano-particles were characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),laser particle size analyzer and differential scanning calorimetry(DSC),respectively.The results show that the Cu nano-particles prepared with PCM as surfactant and N,N-bis-hydroxyethyl dodecyl amide as inactive agent,in pH=4.0-6.5 of the aqueous solution,can be stored in air for 140 days.     

Production of medical radioisotope ~(64)Cu by photoneutron reaction using ELI-NP γ-ray beam

Copper-64 is a radioisotope of medical interest that could be used for positron emission tomography imaging and targeted radiotherapy of cancer. In this work,we investigated the possibility of producing the~(64)Cu isotope through a~(65)Cu(γ,n) reaction using high-intensity γ-beams produced at the Extreme Light InfrastructureNuclear Physics facility(ELI-NP). The specific activity for~(64)Cu was obtained as a function of target geometry, irradiation time, and electron beam energy, which translates into γ-beam energy. Optimized conditions for the generation of~(64)Cu isotopes at the ELI-NP were discussed. We estimated that an achievable saturation specific activity is of the order of 1–2 m Ci/g for thin targets(radius 1–2 mm,thickness 1 cm) and for a γ-beam flux of 10~(11) s ~1. Based on these results, the ELI-NP could provide great potential for the production of some innovative radioisotopes of medical interest in sufficient quantities suitable for nuclear medicine research.