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The shortest-lived is 7 B, with a half-life of a mere 350±50 × 10 −24 s, being the boron isotope with the fewest neutrons and a half-life long enough to measure. Some radioisotopes have important roles in scientific research; a few are used in the production of goods for commercial use or, more rarely, as a component of finished products.
For example, boron trifluoride (BF 3) combines eagerly with fluoride sources to give the tetrafluoroborate anion, BF 4 −. Boron trifluoride is used in the petrochemical industry as a catalyst. The halides react with water to form boric acid. [51] Other boron halides include those with B-B bonding, such as B 2 F 4 and B 4 Cl 4. [55]
Selenium, which is an essential element for animals and prokaryotes and is a beneficial element for many plants, is the least-common of all the elements essential to life. [ 3 ] [ 63 ] Selenium acts as the catalytic center of several antioxidant enzymes, such as glutathione peroxidase , [ 11 ] and plays a wide variety of other biological roles .
A shadow biosphere is a hypothetical microbial biosphere of Earth that uses radically different biochemical and molecular processes than currently known life. It could exist, for example, deep in the crust or sealed in ancient rocks. [citation needed] Silicon biochemistry (Organosilicon) Alternative biochemistry Silicon-based life
Thus boron is not a candidate for life. [38] Arsenic is toxic to life, and its possible candidacy has been rejected. [39] [40] In the past (1960s-1970s) other candidates for life were plausible, but with time and more research, only carbon has the complexity and stability to make large molecules and polymers essential for life. [41] [42] [43]
The elements commonly classified as metalloids are boron, silicon, germanium, arsenic, antimony and tellurium. [n 4] The status of polonium and astatine is not settled. Most authors recognise one or the other, or both, as metalloids; Herman, Hoffmann and Ashcroft, on the basis of relativistic modelling, predict astatine will be a monatomic metal.
These included several elements, of which boron was one, not previously recognized as plant nutrients. Using the solutions he found that all his plants died except those given boron. [7] Warington's work required meticulous care as she had to maintain a boron free solution as her control throughout the life of the beans.
Boron deficiencies effecting seed yields and pollen fertility are common in laterite soils. [45] Boron is essential for the proper forming and strengthening of cell walls. Lack of boron results in short thick cells producing stunted fruiting bodies and roots. Deficiency results in the death of the terminal growing points and stunted growth.