( ( The cryostat ) ( ( ( measures ( the ( heat flow ) ) ) ( through ( ( different ( insulation systems ) ) ( at ( various ( vacuum levels ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NN cryostat)) (VP (VBZ measures) (NP (DT the) (NN heat) (NN flow)) (PP (IN through) (NP (NP (JJ different) (NN insulation) (NNS systems)) (PP (IN at) (NP (JJ various) (NN vacuum) (NNS levels)))))) (. .)))
The cryostat measures the heat flow through different insulation systems at various vacuum levels.
(ROOT (S (NP (DT A) (JJ sealed) (, ,) (JJ vacuum-insulated) (NN reaction) (NN flask)) (VP (VBZ approximates) (NP (NP (DT the) (NN condition)) (PP (IN of) (NP (NP (DT a) (VBN isolated) (NN system)) (, ,) (SBAR (WHPP (IN in) (WHNP (WDT which))) (S (NP (CC neither) (NP (NN matter)) (CC nor) (NP (NN heat))) (VP (MD can) (VP (VB be) (VP (VBN exchanged) (PP (IN between) (NP (NN system) (CC and) (NNS surroundings)))))))))))) (. .)))
A sealed, vacuum-insulated reaction flask approximates the condition of a isolated system, in which neither matter nor heat can be exchanged between system and surroundings.