Question

Preventing the use of rotationally symmetric static fields in this technique can help overcome a limit set by Scherzer’s theorem. The “spot-scan” technique is sometimes used to prevent beam-induced motion in this larger technique. (10[1])Samples in this technique may use heavy metals such as tungsten and osmium to undergo a “negative stain.” The development of a form of this technique, for which Dubochet, (10[1])Frank, and Henderson were awarded the 2017 Nobel Prize in Chemistry, generated a “resolution revolution.” In a form of this technique, the observed specimen is embedded in vitrified ice before being mounted on a grid and fixed (-5[1])via plunging in liquid ethane. For 10 points, name this imaging technique that comes in “scanning,” “transmission,” and “cryogenic” types. ■END■ (10[1]0[1])

ANSWER: electron microscopy [or EM; accept cryogenic electron microscopy or cryo-EM or transmission electron microscopy or TEM or scanning electron microscopy or SEM; prompt on microscopy]
<Minnesota A, Chemistry>
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PlayerTeamOpponentBuzz PositionValue
Nikhil ChellamNorthwestern AIowa3310
Allan LeeStanford BPurdue6210
Jacob FinleyNotre Dame ANorthwestern B99-5
Ved MuthusamyNorthwestern BNotre Dame A1200
Jonah HubertNotre Dame BGeorgetown B12010

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