Yuetsu Danzaki

Comparative Study on Excitation Mechanism of Chromium Emission Lines in Argon Radio‐Frequency Inductively‐Coupled Plasma, Nitrogen Microwave Induced Plasma, and Argon or Nitrogen Glow Discharge Plasmas

Boltzmann plots of both atomic and ionic chromium emission lines are investigated to compare the excitation mechanisms in four different plasmas: an argon inductively‐coupled plasma (Ar‐ICP), a nitrogen high‐power microwave induced plasma (N2‐MIP), an argon glow discharge plasma (Ar‐GDP), and a nitrogen glow discharge plasma (N2‐GDP). The plots of the atomic lines and the ionic lines give both linear relationships as well as similar excitation temperatures in the case of the Ar‐ICP, the N2‐MIP, and the N2‐GDP. It implies that a thermodynamic process such as electron collision would control their excitations. However, only in the case of the ionic‐line plot in the Ar‐GDP, a departure from linear relationship is observed and the estimated excitation temperature is rather higher than that with the atomic lines, meaning that a specific excitation mechanism exists in the Ar‐GDP. A possible explanation for these results is that a charge‐transfer collision between chromium atom and argon ion plays a dominant role in exciting highly‐lying energy levels of chromium ion, especially in the Ar‐GDP.

Determination of sub-μg/g amounts of vanadium in iron by N-benzoyl-N-phenylhydroxylamine-chloroform solvent extraction/ICP-AES

Summary0.05 to 25 μg/g of vanadium in iron was determined by inductively coupled plasma atomic emission spectrometry after solvent extraction using N-benzoyl-N-phenylhydroxylamine-chloroform solution. Vanadium extracted in the chloroform phase was finally transferred into perchloric acid solution and sprayed into the ICP. The analytical line and the correction line for variation in spectral intensity were V II 309.311 nm and Y II 371.030 nm, respectively. Standard deviation and detection limit were 0.03 μg and 0.1 μg.

Preparation of sample solutions for major component analysis of nickel-germanium-iron alloys by ICP-AES

SummaryNickel-germanium-iron alloys were dissolved in nitric-tartaric acids and analysed by ICP-AES. The accuracy was within 1%.

ESCA Investigation of the surface of mixed precipitates

Quantitative ESCA has been used for studying the surface of mixed precipitates. When the precipitation is complete and homogeneous, as with titanium and zirconium hydroxides, almost complete correlation is found between the atomic ratio of the elements in the precipitate and that estimated by the Hirokawa-Ebel method, but not for incomplete mixed precipitation, as with copper and silver hydroxides. When precipitated copper and silver are reduced to the metals with iron or zinc, the surface is enriched in copper.

Use of urea for eliminating chlorine formed in the determination of chromium by ammonium peroxodisulfate oxidation and potassium dichromate back titration

In the determination of Cr by (NH4)2S2O8 oxidation and K2Cr2O7 back titration, urea was used instead of boiling to eliminate Cl2 formed.