Piv nrog tungsten cathodes,lanthanum hexaborate (LaB 6) cathodes muaj qhov zoo xws li tsis tshua muaj hluav taws xob khiav khiav haujlwm, siab emission electron ceev, tsis kam mus rau ion bombardment, zoo tshuaj lom neeg tsis kam, ruaj khov kev ua haujlwm, thiab kev pab lub neej ntev.Nws tau ua tiav hauv ntau yam cuab yeej siv siab thiab cov cuab yeej siv xws li plasma qhov chaw, scanning electron microscopy, electron beam lithography machine, Auger spectroscopy, thiab electron probes.Cov cuab yeej yooj yim ntawmLaB 6, LaB 6, belongs rau CsCI hom cubic primitive lattice.Lanthanum atoms nyob rau yim lub kaum ntawm lub voos xwmfab.Rau boron atoms tsim ib qho octahedron thiab nyob rau ntawm qhov chaw ntawm lub voos xwmfab.Covalent daim ntawv cog lus yog tsim los ntawm BB, thiab cov hluav taws xob tsis txaus thaum lub sij hawm sib txuas ntawm BB yog muab los ntawm lanthanum atom.La muaj valence electron naj npawb ntawm 3, thiab tsuas yog 2 electrons yuav tsum tau koom nyob rau hauv kev sib raug zoo.Qhov seem 1 electron dhau los ua ib qho hluav taws xob dawb.Yog li ntawd, La-B daim ntawv cog lus yog ib daim ntawv cog lus hlau nrog cov khoom siv hluav taws xob zoo heev thiab kev ua haujlwm zoo.Vim yog covalent bonding ntawm B atoms, daim ntawv cog lus lub zog yog siab, lub zog daim ntawv cog lus muaj zog, thiab daim ntawv cog lus ntev yog luv, uas ua rau ib tug compact qauv ntawm LaB6.Nws muaj ib co yam ntxwv xws li siab hardness, siab melting point, thiab kuj nyob ze rautsawg ntiaj teb hlau.
Post lub sij hawm: Sep-28-2023