Gray (unit) Gray (unit) The gray (symbol: Gy) is a derived unit of ionizing radiation dose in the International System of Units (SI). It is defined as the absorption of one joule of radiation energy per kilogram of matter. It is used as a unit of the radiation quantity absorbed dose which measures the energy deposited in a unit mass at a certain position, and of the radiation quantity kerma, which is the amount of energy that is transferred from photons to electrons per unit mass at a certain position. The corresponding cgs unit to the gray is the rad (equivalent to
Energy & Environmental Science journals in the category "Engineering, Chemical", and first among 225 journals in the category "Environmental Sciences". "Energy & Environmental Science" publishes the following types of articles: Research Papers (original scientific work); Review Articles, Perspectives, and Minireviews (feature review-type articles of broad interest); Communications (original scientific work of an urgent nature), Opinions (personal, often speculative, viewpoints or hypotheses on a current topic), and Analysis Articles (in-depth examination of energy and environmental technologies, strategies, policies, and general conceptual frameworks of general interest). According to the Thomson Reuters Master Journal List and CASSI, this journal is indexed by the following services: Energy &