Copper mass spectrometric analysis

Selective removal of olefins was carried out in the absorber with mercury perchlorate, which was prepared in accordance with the recommendations of Coulson [51], who used it in mass spectrometric analysis. The adsorber was prepared by treatment of refractory brick (40—60 mesh) with 1 M mercury perchlorate solution—2 Af perchloric acid (1 1, w/w) and subsequent drying at 110°C. During storage of the absorbent in a closed vessel, no decrease in its activity was observed. Rowan [50] used a layer of mercury perchlorate of height 25 cm in a copper tube of 6 mm diameter for absorption of olefins at 82 or 100 C. A layer (height 12.5 cm) of molecular sieve 4A was used to adsorb the water released from the reactor. The method of selective absorption of unsaturated compounds was used successfully for analysing petrol. 

LF ion attachment MS was apphed to detect [Cu(hfac)(tmvs)], a thermally labile precursor used in copper chemical vapor deposition (Cu-CVD), with the intent of developing improved methods for mass-spectrometric analysis of the CVD proeess [129-131]. A laboratory-built direct introduction system of the sample provided the molecular ion of Cu(hfac)(tmvs) as the LF ion adduct for the first time. 

A free radical procedure for preparing Pb(CH3)4 and mixed tetraalkyllead compounds by passing CH3CI and other alkyl chlorides over a heated mixture of lead and an initiator metal, like copper, is described in [277]. Reaction of lead deposited as a mirror on the inside of a quartz tube with CH3 radicals formed by decomposition of di-tert-butylperoxide is employed to prepare Pb(CH3)4 from small amounts of lead, e.g., from minerals for mass spectrometric analysis [278, 279]. Pb(CH3)4 is formed by reaction of CH3 radicals with recoil products of 224Ra [280, 281, 282] see also [283]. 

Today, as a direct solid-state analytical technique, dc GDMS is more frequently applied for multi-element determination of trace contaminants, mostly of high purity metallic bulk samples (or of alloys) especially for process control in industrial laboratories. The capability of GDMS in comparison to GD-OES (glow discharge optical emission spectrometry) is demonstrated in a round robin test for trace and ultratrace analysis on pure copper materials.17 All mass spectrometric laboratories in this round robin test used the GDMS VG 9000 as the instrument, but for several... 

Remote sampling of up to 20 m makes the system attractive for the analysis of large items. On the other hand, the system is also useful for precision analyses both by atomic absorption and plasma spectrometric methods. The analysis of electrically non-conductive powders is also possible, where a mixture of the powder to be analyzed and copper powder in a ratio of about 1 5 can be made and briquetted into a pellet. This can be realized by using pressures of up to 80 Torr/cm2, as has been described for glow discharge work by El Alfy et al. [210], The mass ratio of analyte to copper may, however, differ considerably from one sample base to another. 

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