비의류제품

recycling waste-paper

  • 출판일1999.03
  • 저자
  • 서지사항
  • 등록일 2016.11.02
  • 조회수 512
perhaps 80 percent of papermaking energy is expended in chemical pulping of vegetable cellulose, a natural polymer. commercial supplies of wood, bagasse, cotton and flax are valued as renewable resources and bio-mass assets; however, few enterprises will salvage waste-paper and cardboard from their trash. a basic experiment in the materials lab uses simple equipment to make crude handsheets students learn to classify secondary fibers, identify contraries, and estimate earnings
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