USP <841> Specific Gravity的要求

blackvane

大家好：
       最近重新阅读了USP <841> Specific Gravity，温故知新，发现有2点不是很理解，想求教各位：
       1） Method I中提到“When the monograph specifies a temperature different from 25°, filled pycnometers must be brought to the temperature of the balance before they are weighed.”
      问题：若正文的要求不是在25℃，则要求将比重瓶的温度控制到与天平相同温度，然后再称量。这个实际是怎么操作？怎么知道天平的温度？
       2）MethodII中提到“Density meters are able to achieve measurements with an error on the order of 1×10–3 g/cm3 to 1×10–5 g/cm3 and a repeatability of 1×10–4 g/cm3 to 1×10–6 g/cm3. For example, an instrument specified to ±1×10–4 g/cm3 must display 0.9970±0.0001 g/cm3 in order to be suitable for further measurement, otherwise a readjustment is necessary.”
      问题：是指仪器测定结果的显示屏幕上一定要能显示“0.9970±0.0001 g/cm3”，特别是“±0.0001”？如果不是“readjustment”应如何操作？这个背后隐藏的意思是什么?
  求教了，感谢！

blackvane

自己顶一下。