环

• The rings are not the solid sheets they appears to be .
  环并不是看上去那样的固体薄板。
• Some pistons have seating rings of metal or leather .
  有些活塞上有金属或皮革的密封环。
• The expected 2＋2 cycloadduct (79) was not observed .
  未见到所预期的22环加成物（79）
• These rings are called gyres .
  这些环叫做转环。
• Two moles of epoxy react with one mole of a-1100 .
  两个克分子环氧与一个克分子A1100反应。
• In multiple-ring systems very complex patterns are produced .
  多环体系常产生很复杂的谱图。
• A variety of cyclopropanes are thus produced in good yield .
  从而以高收率得到带各种环丙烷。
• One of the links of the chain that drives the wheels had snapped .
  轮子的链条上断了只链环。
• This is the important link for problems of subsurface flow .
  这是解决地下水问题的重要一环。
• The feed reactants can be alkadienes, cycloalkadienes .
  所加的反应物可以是二烯烃、环二烯烃。