Question: process by which nitrogen is obtained from air on a large scale
[{'answer': 'air separation', 'provenance': [{'wikipedia_id': '23096495', 'title': 'Air separation', 'start_paragraph_id': 1, 'start_character': 3, 'end_paragraph_id': 1, 'end_character': 17, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '23096495', 'title': 'Air separation', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 161, 'bleu_score': 0.9181891462193901, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 1963867895121854030}, 'section': 'Section::::Abstract.'}]}]