| 摘要 |
<p>1,267,411. Denitrifying steel plate. NIPPON STEEL CORP. Jan.29, 1969 [Jan.30, 1968], No.4868/69. Heading C7D. Open coils of steel plate have circulated through them a denitrifying gas, such as moist hydrogennitrogen mixture, the gas then being brought into contact with ammonia-decomposing agent at a temperature of 400‹ to 850‹C. and then recycled. The treating agent may be an aluminium-killed steel plate, or may be an alloy of Fe with B, Al, Si, V or Cr in ribbon or granular form. Preferred compositions require more than 0À02% of Al or B, more than 0À05%V or more than 1% of Si or Cr. Reference has been directed by the Comptroller to Specification 1,187, 838.</p> |
