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Boron is a component of neodymium magnets (Nd 2 Fe 14 B), which are among the strongest type of permanent magnet. These magnets are found in a variety of electromechanical and electronic devices, such as magnetic resonance imaging (MRI) medical imaging systems, in compact and relatively small motors and actuators.
Boron group. The boron group are the chemical elements in group 13 of the periodic table, consisting of boron (B), aluminium (Al), gallium (Ga), indium (In), thallium (Tl) and nihonium (Nh). This group lies in the p-block of the periodic table. The elements in the boron group are characterized by having three valence electrons. [1]
Isotopes of boron. , the latter of which makes up about 80% of natural boron. There are 13 radioisotopes that have been discovered, with mass numbers from 7 to 21, all with short half-lives, the longest being that of 8. with a half-life of 20.20 (2) ms. All other isotopes have half-lives shorter than 17.35 ms.
Boranes are chemical compounds of boron and hydrogen, with the generic formula of B x H y. These compounds do not occur in nature. Many of the boranes readily oxidise on contact with air, some violently. The parent member BH 3 is called borane, but it is known only in the gaseous state, and dimerises to form diborane, B 2 H 6.
In atomic physics, the Bohr model or Rutherford–Bohr model was the first successful model of the atom. Developed from 1911 to 1918 by Niels Bohr and building on Ernest Rutherford 's nuclear model, it supplanted the plum pudding model of J J Thomson only to be replaced by the quantum atomic model in the 1920s.
Allotropes of boron. Boron can be prepared in several crystalline and amorphous forms. Well known crystalline forms are α-rhombohedral (α-R), β-rhombohedral (β-R), and β-tetragonal (β-T). In special circumstances, boron can also be synthesized in the form of its α-tetragonal (α-T) and γ-orthorhombic (γ) allotropes.
18 February 1965 [2] Designated CL. 27 October 1971 [3] Chicago Pile-1 (CP-1) was the world's first artificial nuclear reactor. On 2 December 1942, the first human-made self-sustaining nuclear chain reaction was initiated in CP-1 during an experiment led by Enrico Fermi. The secret development of the reactor was the first major technical ...
v. t. e. In physical cosmology, Big Bang nucleosynthesis (also known as primordial nucleosynthesis, and abbreviated as BBN) [1] is the production of nuclei other than those of the lightest isotope of hydrogen (hydrogen-1, 1 H, having a single proton as a nucleus) during the early phases of the universe. This type of nucleosynthesis is thought ...