▁holder ▁capable ▁of ▁maintain ing ▁the ▁spec imen ▁at ▁liquid ▁nit ro gen ▁or ▁liquid ▁hel ium ▁temper atures . ▁This ▁allows ▁imag ing ▁spec im ens ▁prepared ▁in ▁vit re ous ▁ice , ▁the ▁preferred ▁prepar ation ▁technique ▁for ▁imag ing ▁individual ▁mole cules ▁or ▁mac rom ole cular ▁assemb lies , ▁imag ing ▁of ▁vit r ified ▁solid - elect ro ly e ▁interfaces , ▁and ▁imag ing ▁of ▁materials ▁that ▁are ▁vol atile ▁in ▁high ▁vac u um ▁at ▁room ▁temperature , ▁such ▁as ▁sul fur . ▁ ▁Environment al / In - s itu ▁T EM ▁In - s itu ▁experiments ▁may ▁also ▁be ▁conducted ▁in ▁T EM ▁using ▁differential ly ▁p ump ed ▁sample ▁ch amb ers , ▁or ▁special ized ▁hold ers . ▁Types ▁of ▁in - s itu ▁experiments ▁include ▁studying ▁nan om aterial s , ▁bi ological ▁spec im ens , ▁and ▁chemical ▁re actions ▁ ▁using ▁ ▁liquid - phase ▁electron ▁micro sc opy , ▁and ▁material ▁de formation ▁testing . ▁ ▁Aber r ation ▁Correct ed ▁T EM ▁Modern ▁research ▁T EM s ▁may ▁include ▁aber r ation ▁correct ors , ▁to ▁reduce ▁the ▁amount ▁of ▁dist ort ion ▁in ▁the ▁image . ▁Inc ident ▁beam ▁mon och rom ators ▁may ▁also ▁be ▁used ▁which ▁reduce ▁the ▁energy ▁spread ▁of ▁the ▁incident ▁electron ▁beam ▁to ▁less ▁than ▁ 0 . 1 5   e V . ▁Major ▁aber r ation ▁corrected ▁T EM ▁manufact ur ers ▁include ▁J E OL , ▁Hit achi