Lathanum hexaborate cathode mea hoopuka

lab6

Hoʻohālikelike ʻia me nā cathodes tungsten,lanthanum hexaborate (LaB6) nā cathodes i nā pono e like me ka haʻahaʻa electron pakele hana, kiʻekiʻe emission electron density, kū'ē i ka ion bombardment, maikaʻi poisoning kū'ē, paʻa hana, a me ka lōʻihi lawelawe ola. Ua hoʻohana maikaʻi ʻia i loko o nā mea hana kiʻekiʻe a me nā mea hana e like me nā kumu plasma, scanning electron microscopy, electron beam lithography machines, Auger spectroscopy, a me electron probes. Ka waiwai kumu oLaB6, LaB6, no ka CsCI type cubic primitive lattice. Noho nā ʻātoma Lanthanum i nā kihi ʻewalu o ka pahu. Hoʻokumu ʻia nā ʻātoma boron ʻeono i kahi octahedron a aia ma ke kikowaena o ka pahu. Hoʻokumu ʻia ka paʻa covalent ma waena o BB, a hāʻawi ʻia nā electrons lawa ʻole i ka wā o ka hoʻopaʻa ʻana ma waena o BB e ka lanthanum atom. Loaʻa iā La ka helu electron valence o 3, a he 2 mau electrons wale nō e pono e komo i ka hoʻopaʻa ʻana. ʻO ke koena 1 electron e lilo i electron manuahi. No laila, ʻo ka paʻa La-B he paʻa metala me ka conductivity kiʻekiʻe loa a me ka conductivity maikaʻi. Ma muli o ka hoʻopaʻa ʻana o ka covalent ma waena o nā ʻātoma B, ʻoi aku ka kiʻekiʻe o ka ikehu paʻa, ikaika ka paʻa paʻa, a pōkole ka lōʻihi o ka hoʻopaʻa ʻana, e hopena i kahi ʻano paʻa o LaB6. Loaʻa iā ia kekahi mau hiʻohiʻona e like me ka paʻakikī kiʻekiʻe, ka helu heheʻe kiʻekiʻe, a me ke kū'ē kokokemetala lepo laha ole.


Ka manawa hoʻouna: Sep-28-2023