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11.
The optogalvanic effect of neon, in the presence of CO gas, has been specifically investigated for the 630.2 nm transition. Our theoretical model, based on rate equations, predicts well the observed signals as a sum of exponential functions. 相似文献
12.
The optogalvanic effect of neon,in the presence of CO gas,has been specifically investigated for the 630.2 nm transition.Our theoretical model,based on rate equations,predicts well the observed signals as a sum of exponential functions. 相似文献
13.
Applicability of total reflection X-ray fluorescence (TXRF) spectrometry for trace elemental analysis of rainwater samples
was studied. The study was used to develop these samples as rainwater standards by the National University of Singapore (NUS).
Our laboratory was one of the participants to use TXRF for this study. The rainwater sample obtained from NUS was analysed
by TXRF and the trace elements Mn, Fe, Ni, Cu, Zn, V and Pb were determined as required by the NUS. The average precision
was found to be within 16% and the TXRF-determined elemental concentrations of these elements were below 20 μg/l. The average deviation of TXRF-determined values from the certified values were 20% (excluding the deviation for Fe and
V which were comparatively high). Apart from the above elements, S, K, Ca, Rb, Sr, Ba and Br were also determined by TXRF
and were found to be in the range of 0.2 to 191 μg/l. TXRF-determined values of our laboratory played an important role in the certification of concentration of seven elements
in this rainwater sample which was later developed as a rainwater standard. 相似文献
14.
Uranium is reported to be present in phosphate fertilizers. The recovery of uranium from the fertilizers is important because
it can be used as fuel in nuclear reactors and also because of environmental concerns. For both these activities suitable
method of uranium determinations at trace levels in these fertilizers are required. Studies have been initiated for such TXRF
determination of uranium and the results are reported in the present paper. For TXRF determinations the fertilizer samples
were processed with nitric acid and the uranium present in it was removed by solvent extraction using tri-n-butyl phosphate
as the extractant. The organic phase containing uranium was equilibrated with 1.5% suprapure nitric acid to bring out uranium
in aqueous phase. This aqueous phase was mixed with internal standard Y and the TXRF spectra were measured by depositing samples
on float glass supports. The amounts of uranium in four fertilizer samples of Hungarian origin were determined by processing
these TXRF spectra. Uranium concentrations in two fertilizer samples were found to be in the range of 4–6 μg/g, whereas two fertilizer samples did not show the presence of uranium. The precision of the TXRF determination of uranium
was found to be better than 8% (1σ). 相似文献