Effect of Ultra-Trace Impurities on the Freezing Point of Zinc

The technique is described of achieving the highest accuracy of measurement with platinum-resistance thermometers at the freezing point of zinc and the boiling point of sulphur. The two points are compared in a series of measurements and it is found that the zinc point is some three or four times more reproducible than the sulphur point. It is concluded that the substitution of the zinc point for the sulphur point as a primary fixed point of the International Temperature Scale would lead to a greater precision in the definition of the scale. The value of the freezing point of zinc is found to be 419∙5055 ± 0∙002°C.

Download Full-text

Determination of ultra-trace impurities in high purity gallium arsenide by inductively coupled plasma mass spectrometry after volatilization of matrix

Journal of Analytical Atomic Spectrometry ◽

10.1039/b312414m ◽

2004 ◽

Vol 19 (3) ◽

pp. 407 ◽

Cited By ~ 11

Author(s):

A. C. Sahayam ◽

Shiuh-Jen Jiang ◽

Chia-Ching Wan

Keyword(s):

Mass Spectrometry ◽

Gallium Arsenide ◽

High Purity ◽

Inductively Coupled Plasma ◽

Trace Impurities ◽

Inductively Coupled ◽

Plasma Mass Spectrometry ◽

Ultra Trace

Download Full-text

Effect of Impurities on the Freezing Point of Zinc

International Journal of Thermophysics ◽

10.1007/s10765-016-2173-7 ◽

2017 ◽

Vol 38 (3) ◽

Author(s):

Jianping Sun ◽

Steffen Rudtsch ◽

Yalu Niu ◽

Lin Zhang ◽

Wei Wang ◽

...

Keyword(s):

Freezing Point ◽

Effect Of Impurities ◽

Freezing Point Of Zinc

Download Full-text

Electrodes for Trace Impurity Analysis and Determination of Traces in Gallium

Applied Spectroscopy ◽

10.1366/000370270774372083 ◽

1970 ◽

Vol 24 (1) ◽

pp. 60-67 ◽

Cited By ~ 5

Author(s):

M. S. Wang

Keyword(s):

Signal To Noise Ratio ◽

Sampling Technique ◽

Trace Determination ◽

Trace Impurities ◽

Graphite Electrodes ◽

Impurity Analysis ◽

Gallium Metal ◽

Ultra Trace ◽

Dc Arc

Electrodes of several graphite makers have been evaluated and compared for weight consistency and impurities for the purpose of developing techniques to determine trace impurities in material which can take advantage of preferential volatilization. A technique suitable for pre-arcing graphite electrodes in an argon atmosphere has been developed for minimizing the impurity background in the electrode cup so that ultra-trace determination is possible. The purified and selected electrodes are used in development of a spectrochemical method for determining trace impurities in gallium metal. The technique takes advantage of strong preferential volatilization of the metals in a dc arc with sequential exposures used for improvement of signal-to-noise ratio. A new sampling technique and standardization method are discussed. Special problems related to the analysis of gallium are investigated, and analytical results are shown.

Download Full-text