You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["Chemical"].

Please return the output as a JSON object of the format: {"Chemical": ["Arsenic", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

Thermorheological complexity and fragility in plasticized lignocellulose. It is demonstrated that plasticized lignocellulose fails to satisfy classic criteria normally required to validate time/temperature superposition (TTS) in dynamic mechanical analysis (DMA). However, insightful relaxation behavior is available and dismissing it would be a mistake. TTS was applied to Liriodendron tulipifera wood using parallel plate compressive-torsion DMA with specimens immersed in different organic liquids, ranging from weak to strong swelling power. While all storage moduli shifted smoothly, thermorheological complexity was detected in loss modulus shift failures, which themselves must reflect unknown structural features. Storage modulus shift factors clearly distinguished solvent specific relaxation behavior and interpretations through the WLF model or through fragility (cooperativity) analysis are useful. However, it is demonstrated that fragility analysis is preferred and solvents of different swelling power are compared. Coupled with other methods, TTS and fragility analysis warrant further development as a means to improve the understanding of structure/property relationships in plasticized lignocellulose.
{"Chemical": []}