copper

• The copper is disseminated in small joint surfaces and cracks in the porphyries .
  铜浸染在斑岩的细小节理面和裂隙中。
• About half of the world's known supply of copper ore is already in use .
  全世界已知的铜矿储量，大约有一半已在使用了。
• Copper atoms are replaced by zinc atoms as the amount of zinc is increased .
  随着锌量的增加，铜原子逐步为锌原子所替代。
• Sometimes the carbon rods are copper coated to improve electrical conductivity .
  有时这些碳棒包上一层铜，以增加其导电性。
• Among the mineral deposits of the province , tin occupies first place ; copper comes second .
  该省矿藏，以锡最多，铜次之。
• Iron or steel placed in copper sulfate also receives a loose immersion deposit .
  铁或钢放入硫酸铜中，也会生成疏松的浸镀层。
• The rate at which pulses can be sent and received on copper wires is called frequency .
  脉冲通过铜线送出和接收的速度称为频率。
• When the gyro is vertical, the magnet is directly below the center of the disk of copper .
  当陀罗处于垂直位置时，磁铁就在铜片中心下。
• The signals carried in copper wires consist of about one million waves per second .
  在铜线中传送的信号是由大约每秒100万次波的电磁波所组成。
• The new boy took two broad coppers out of his pocket and held them out with derision .
  新来的孩子从口袋里掏出两个大铜板，显出讥讽的神气伸出手来。