The Biden administration has added seven Chinese supercomputer research labs and manufacturers to a US export blacklist in a spreading conflict with Beijing over technology and security. The measure announced Thursday is the latest sign President Joe Biden is sticking to the tough line taken by his predecessor, Donald Trump, toward Chinese tech industries seen by Washington as potential threats. The decision adds to mounting conflict over the ruling Communist Party's industrial plans, access to American technology and accusations of computer attacks and theft of business secrets. The latest penalties block access to US technology for researchers and manufacturers the Commerce Department said build supercomputers used by the Chinese military in weapons development.