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:

Phytochemical analysis of the essential oils of 10 endemic Cephalaria species from Turkey. The volatile composition of 10 endemic Cephalaria (Dipsacaceae) species (Cephalaria gazipashensis, Cephalaria lycica, Cephalaria paphlagonica, Cephalaria elmaliensis, Cephalaria stellipilis, Cephalaria scoparia, Cephalaria isaurica, Cephalaria cilicica, Cephalaria elazigensis var. purpurea and Cephalaria davisiana) was investigated. The essential oil mixtures were obtained by steam distillation in a Clevenger-type apparatus. Twenty-eight components were identified by GC-FID and GC-MS techniques. While total volatile percentages ranged from 68.99% to 84.57%, the total essential oil yields ranged between 38.15% and 64.05%. Geraniol, α-cedrene and p-cymene were determined as the main components. Geraniol was detected as a major component in C. cilicica (14.64%), and α-cedrene was detected as a major component with 26.03% for C. lycica, 16.93% for C. scoparia, 13.01% for C. davisiana and 10.94% for C. paphlagonica. Cephalaria scoparia, C. davisiana and C. gazipashensis have considerable amount of p-cymene as 12.86%, 12.70% and 11.16%, respectively. This was the first essential oil report concerning the Cephalaria genus.
{"Chemical": ["Geraniol", "\u03b1-cedrene", "p-cymene"]}