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     ;  羽(yu)(yu)絨(rong)(rong)是(shi)長在鵝、鴨的腹(fu)部，成蘆花朵(duo)狀的絨(rong)(rong)毛，成片狀的叫羽(yu)(yu)毛。由(you)于(yu)羽(yu)(yu)絨(rong)(rong)是(shi)一種動物性(xing)蛋白(bai)質(zhi)纖維，比棉花（植(zhi)物性(xing)纖維素）保溫(wen)(wen)性(xing)高，且羽(yu)(yu)絨(rong)(rong)球狀纖維上密布(bu)千(qian)萬個三角形的細小(xiao)氣孔，能隨氣溫(wen)(wen)變化(hua)而(er)收縮膨脹(zhang)，產生(sheng)調溫(wen)(wen)功能，可吸(xi)收人(ren)體(ti)散發流動的熱氣，隔絕(jue)外(wai)界冷空(kong)氣的入侵。