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(一) 引言自從1871年,蘇聯大化學家門德列夫氏,將各種元素排列成週期表後,對被遺漏的元素,起了預示和啟發的作用。現在元素為我們所知道的,已有九十六種。其中約一打之數,佔地球上全物質93％以上,其餘元素,則比較希有。有三十種元素,可於地球上得其自由狀態;大多數僅於化合狀態下見之。在大氣
(1) Introduction Since 1871, the great chemist of the Soviet Union, Mende Lev, arranged various elements into a periodic table and played the role of a precursor and inspiration to the missing elements. Ninety-six kinds of elements are now known to us. About a dozen of them, accounting for more than 93% of the earth’s total material, the rest of the elements, the more hope. There are thirty kinds of elements which can be freely found on the earth; most of them are only seen in the compound state. In the atmosphere