Scientists invent lead-free composite shielding material for neutrons and gamma-rays

Phys.org  December 23, 2021 Through a series of intricate and comprehensive experiments researchers in China tested and certified the composite, modified-gadolinium oxide/boron carbide/high density polyethylene (Gd2O3/B4C/HDPE) as safe and effective to shield neutron and gamma rays. Fast neutrons collide with gadolinium (Gd) inelastically and collide elastically with hydrogen until they become thermal neutrons, finally, absorbed by high Z element Gd and boron. The experimental results show that the neutron shielding rate of the composite can reach 98% under the condition of 15 cm thickness in CF-252 environment. In cS-137 and CO-60 environments, the gamma shielding rates of the composite are […]

Testing Chernobyl fungi as a radiation shield for astronauts

Phys.org  July 27, 2020 Certain fungi thrive in high-radiation environments on Earth, such as the area around the Chernobyl Nuclear Power Plant. These organisms appear to perform radiosynthesis using pigments known as melanin to convert gamma-radiation into chemical energy. A team of researchers in the US (University of North Carolina, Stanford University) cultivated a 1.7 mm think lawn of Cladosporium sphaerospermum of the melanized radiotrophic fungus and tested its capability to attenuate ionizing radiation on the International Space Station over a time of 30 days. They found that the radiation below the lawn was 2.17±0.35% lower compared to the negative […]

New biomaterial could shield against harmful radiation

Phys.org  July 8, 2020 Melanins are a family of heterogeneous biopolymers found ubiquitously across plant, animal, bacterial, and fungal kingdoms where they act variously as pigments and as radiation protection agents. An international team of researchers (USA – Northwestern, UC San Diego, University of Akron, Belgium) synthesized ” selenomelanin” enriching melanin with selenium instead of sulfur to provide better protection against X-rays as selenium is an essential micronutrient that plays an important role in cancer prevention. Results demonstrated that selenomelanin offers superior protection from radiation, it is easy to synthesize. Selenomelanin can be biosynthesized, with appropriate nutrients can produce selenomelanin […]

Researchers develop smaller, lighter radiation shielding

Science Daily  February 12, 2020 Commonly used shielding in aerospace devices consists of putting an aluminum box around any sensitive technologies has been viewed as providing the best tradeoff between a shield’s weight and the protection it provides. A team of researchers in the US (industry, North Carolina State University) has developed a technique that relies on mixing oxidized metal powder — rust — in a polymer, and then incorporating it into a common conformal coating on the relevant electronics. Radiation transport calculations show that inclusion of the metal oxide powder provides shielding comparable to a conventional shield, at low […]