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众所周知,尘埃就是浮游在空气中的微粒子、尘土、细沙、烟尘等。人们习惯上把空气中的尘埃分为飘尘和降尘两种,飘尘的直径一般小于10微米,可以较长时期悬浮在空中,凭着空气的浮力,常常随风飘游,无孔不入;而降尘直径常常大于10微米,在静风状态下,1-7天内会沉降于下垫面。尘埃的来源主要有三个:人类活动、地壳的自然风化和宇宙间的天体运动。根据世界气象组织统计,近年来全球范
As we all know, dust is the particles floating in the air, dust, sand, dust and so on. People are accustomed to the dust in the air is divided into two kinds of dust and dust, the diameter of dust is generally less than 10 microns, can be suspended in the air for a longer period of time, with the buoyancy of the air, often drift in the wind, all-pervasive; and dustfall diameter is often greater than 10 microns, in a calm state, will fall to the underlying surface within 1-7 days. There are three main sources of dust: human activity, natural weathering of the earth’s crust, and celestial movement in the universe. According to the statistics of the World Meteorological Organization, the global scale has come in recent years