Thus, for high-energy neutrons, beryllium is a neutron multiplier, releasing more neutrons than it absorbs. This nuclear reaction is: [19] 9 4 Be + n → 2 4 2 He + 2 n. Neutrons are liberated when beryllium nuclei are struck by energetic alpha particles [18] producing the nuclear reaction 9 4 Be + 4 2 He → 12 6 C + n. where 4 2 He is an ...

The ground state of the nuclide technetium-99 is used as a gamma ray–free source of beta particles. ... At high pressure formation of TcH 1.3 from elements was also ... is the most stable, with a half-life of 91 days and excitation energy 0.0965 MeV. [58] This is followed by technetium-95m (61 days, 0.03 MeV), and technetium-99m (6.01 hours ...

A fullerene is an allotrope of carbon whose molecules consist of carbon atoms connected by single and double bonds so as to form a closed or partially closed mesh, with fused rings of five to six atoms. The molecules may have hollow sphere- and ellipsoid-like forms, tubes, or other shapes.. Fullerenes with a closed mesh topology are informally denoted by their empirical formula C n, often ...

Archaea (/ ɑːr ˈ k iː ə / ⓘ ar-KEE-ə) is a domain of organisms.Traditionally, Archaea only included its prokaryotic members, but this since has been found to be paraphyletic, as eukaryotes are now known to have evolved from archaea. Even though the domain Archaea cladistically includes eukaryotes, the term "archaea" (sg.: archaeon / ɑːr ˈ k iː ɒ n / ar-KEE-on, from the Greek ...

The economy of the People's Republic of China is a developing mixed socialist market economy, incorporating industrial policies and strategic five-year plans. [29] China is the world's second largest economy by nominal GDP and since 2017 has been the world's largest economy when measured by purchasing power parity (PPP). [30] [note 2] China accounted for 19% of the global economy in 2022 in ...