我们知道,地球上绝大多数物质的存在形态同温度密切相关,随着温度由低向高的上升,物质可以从固态融化为液态,再蒸发为气态。但是一般物质在适当的温度和压力之下,可以变成一种既非气体、也非液体,既是气体、也是液体的浑沌状态,科学家称之为“超临界流体”。例如,常温常压下的CO_2是 We know that the existence of most substances on the Earth is closely related to temperature. As the temperature rises from low to high, the material can be melted from a solid state to a liquid state and then evaporated to a gaseous state. However, under the appropriate temperature and pressure, general substances can become a chaotic state that is neither gas nor liquid, and is both gas and liquid. Scientists call it “supercritical fluid.” For example, CO_2 at normal temperature and pressure is