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臭氧

A blue gaseous allotrope of oxygen, O3, formed naturally from diatomic oxygen by electric discharge or exposure to ultraviolet radiation. It is an unstable, powerfully bleaching, poisonous oxidizing agent with a pungent, irritating odor, used to deodorize air, purify water, treat industrial wastes and as a bleach.

臭氧一种气态氧气的同素异形体，O3在紫外线辐射下通过电子放射或暴晒从双原子氧气自然形成。它是一种不稳定的具有强漂白性的，有毒的氧化剂，有臭的刺激性的气味，用来除去空气的异味，净化水，处理工业废物和作为漂白剂

Co-movement

A key feature of the Burns and Mitchell economic was to focus on the amount of cyclical co-movement or coherence among a large number of economic variables. This co-movement is the prime characteristic of their definition of the business cycle: "...a cycle consists of expansions occurring at about the same time in many economic activities, followed by similarly general recessions, contractions, and revivals which merge into the expansion phase of the next cycle;...in duration business cycles vary from more than one year to ten or twelve years..."

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