 Los Angeles, CA, June 09, 2021 GLOBE NEWSWIRE -- via NewMediaWire -- On June 4, 2021, US Nuclear OTCQB: UCLE signed an agreement to take a 5 stake in Solar System Resources Corporation Sp. z o. o., thus advancing US Nuclears portfolio of high-tech startups. US Nuclear and Solar System Resources decided to keep the details of the transaction private. 