Sentence:  Volatiles of "kecap manis" and its raw materials were extracted using Likens-Nickerson apparatus with diethyl ether as the extraction solvent. The extracts were then dried with anhydrous sodium sulfate, concentrated using a rotary evaporator followed by flushing using <WSD>nitrogen</WSD> until the volume was about 0.5 ml. 
Meaning of the word marked with <WSD> tags:  Molecular nitrogen (N<sub>2</sub>), a colorless, odorless gas at room temperature.