Natural mineral compounds consist of carbon, hydrogen, sulphur and nitrogen or the residue from distillation of petroleum, coal tar or rosin.

 
  • 天然产生的沥青是含有碳、氢、硫和氮的矿产化合物。人造沥青是蒸溜石油,煤焦油或松脂后的余下渣滓。
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