For the precise and accurate quantitative analysis by a spark source mass spectrograph, the effects of source parameters on the ion intensities were investigated for various elements in iron, nickel, copper, aluminum and zinc matrices.
Ion intensities were not varied by change of pulse width at 1020 μsec, but decreased with the ion accelerating voltage. In iron matrix, a group of elements increased ion intensities with increasing spark voltage, while the other group decreased intensities. The same tendency was observed in copper matrix with rate of pulse repetition. It was considered that these phenomena depended on the difference in the heat of sublimation of the matrix and component elements. Since the effects of the source parameters are varied with matrix and elements, the source should be kept constant during the measurement, and analyzing and standard samples must be measured under the same condition.

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A new method for the determination of nitrogen in iron and steel has been investigated. Samples were mixed with red lead and fused in helium carrier. After the oxygen, hydrogen and carbon dioxide in gases formed were removed with cupric oxide, metallic copper and molecular sieve 5A, the residual gases containing nitrogen were introduced into a thermal conductivity cell by a pumping system. The signal for nitrogen was recorded and counted with an integrator. Because this method employed an open fusion system, samples could be inserted and exchanged easily and rapidly. Calibration curves were linear. Metallic nitrides were decomposed throughly and nitrogen was extracted comletely. Analytical values by this method agreed with the values by the wet chemical method. The reproducibility was 35% by coefficient of variation and the lower limit of determination was 10 ppm by weight. The proposed method using a porcelain crucible is suitable for the routine determination of nitrogen in iron and steel.

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Iron (III) reacts with any of phenylenediamine isomers to form complexes with different colouration. Based on this fact, the separation of phenylenediamine isomers by ligand exchange chromatography has been investigated, in which sulfonated cation exchange resin Amberlite CG-120 (Fe³⁺ form) was used as a stationary phase and diluted aqueous ammonia as a developer.
Studies on the adsorption behaviours of these three isomers on the resins showed that the distribution coefficients decreased with increasing concentration of ammonia and that the retention volume of P-isomer varied with the flow rate of developer because of its slow adsorption rate. Iron (III) -phenylenediamine complexes formed in the resin phase were of mole ratio 1 : 1 for ο-isomer and 1 : 2 for m- and P-isomers.
The separation of three isomers was successful when a mixture was eluted through a column of φ 18 mm×753 mm with 5×10^-3M aqueous ammonia at a flow rate of 0.5 ml/min., whereby the loss of metal ion from the column was avoided.

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β-Mercaptohydrocinnamanilide (MHCA) and β-mercaptocinnamanilide (MCA) were prepared as new chelating agents containing mercapto and amide groups, and their application to the determination of nickel and cobalt was investigated. The nickel chelate of MHCA could be extracted into chloroform, while the cobalt chelate of MCA could be extracted into isoamyl acetate. Determination of nickel by MHCA and that of cobalt by MCA both within 10 and 100 ppm were found to be possible by the measurement of the absorbance at 430 mμ and 640 mμ, respectively. The molar ratio of the nickel chelate was 2: 1 and the cobalt chelate 3 : 1. As these reagents are stabler than the ordinary mercapto compounds, they are considered to be useful analytical reagents.

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Concentration of dilute acid or salt were determined by measurement of heat of ion exchange by using a thermistor. Anion exchange resin (NO₃-type) was packed in a detection column, 5 cm in length and 8 mm in diameter, and a thermistor was inserted near the bottom on the axis of the column.
The column was placed in thermostat maintained exactly at 30°C. The eluting agent was a dilute solution of acid or salt having anion common with the sample solution to be injected.
When the concentration of the sample was different from that of the eluting agent, peak was appeared on the thermogram, and the peak-height was greater than the case when the cation exchange resin was packed in the detection column.
By making the volume of the sample constant, the peak-heights were proportional to the concentration of sample solution, which was then determined referring to the calibration curve of peak-height vs. concentration of the standard solution.

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The spectral intensities of concerning elements were affected by the nature and concentration of coexistent components. Addition of elements having the ionization potentials lower than 6 eV increases the spectral intensities, and, especially, the coexistence of Cs, Na, Rb and Ba remarkably increases the sensitivities. The optimum concentrations of the coexistent elements which give the highest intensity depend linearly on their ionization potentials. That is, the lower the ionization potentials of the coexistent elements, the higher their optimum concentrations. The addition of ethanol increases the spectral intensity and sensitivity of rare earth elements.

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The standardization method for gases used for the calibration of a measuring apparatus has been standardized as yet.
The present work deals with the standardization of sulfur dioxide gas for the calibration.
After measurement of the volume of the sample gas, containing about 1000 ppm of sulfur dioxide balanced with nitrogen, sulfur dioxide was absorbed into iodine, hydrogen peroxide or sodium tetrachloromercurate solution.
The final determination was carried out by iodometric or coulometric titration.
Two methods were examined for the absorption of sulfur dioxide.
The one was the " static " method in which sulfur dioxide was absorbed in the sampling bottle into which the, absorbing solution was introduced, and the other was the " dynamic " method in which the sample gas was passed through the absorption tubes outside the sampling vessel.
The static method with sodium tetrachloromercurate as the absorbent followed by the coulometric titration was recommended by the authors.

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Rapid qualitative analysis of phenol- and cresol-formaldehyde resins was studied by pyrolysis gas chromatography on samples of cured and uncured resins of Novolak and Resol types. The pyrolysis was done in helium gas at 800°C in a filament type apparatus. The reproducibility of the result in 10 measurements was ca. 20%. Phenol-formaldehyde resin was distinguished from cresol-formaldehyde resin semiquantitatively by the fact that the former gave much phenol and o-cresol by the pyrolysis. Rapid qualitative analysis on cured and uncured resins was done successfully by the proposed method.

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The boron-curcumin complex formed in sulfuricacetic acid media was extracted with methylethylketone-chloroform-phenol mixture. The maximum absorption wavelength was 555 mμ. The molar extinction coefficient of the complex was 170, 000 mol ^-1.l·cm·^-1, at 555 mμ, and the detection limit was 0.025 μg B/ 10 ml.
This was applied to the determination of microamounts of boron in steel, and a method was established in which about 0.0001% of boron was determined successfully after the removal of iron by MIBK extraction.

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Square-wave polarographic determination of microamounts of tin (0.11.0 μg/ml) was studied and applied to the analysis of canned juice as follows. One gram of sample is dissolved with the mixed acid (HNO₃ and H₂SO₄) and then urea is added. After the dilution with water, an aliquot is made up to volume with a mixture of CH₃COOH, CH₃COONH₄ and ascorbic acid used as the supporting electrolyte, and the square wave polarogram is recorded between -0.3-0.8V for tin vs. S. C. E. Cadmium wave overlaps with tin wave, but Pb, As, Sb, Zn, Cu, Ni and Co within the limit of the utility standard by Japanese Food Hygienic Law do not interfere with the determination. The time required for an analysis is about 2 hours.

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Fundamental investigations were carried out on aquiring a high sensitivity and precision by decreasing continuous emission background in emission spectrographic analysis utilizing plasma-jet as a light source. The background intensity decreased by increasing a spray gas pressure. When flow rate of arc gas was Ar 12+ He 8 l /min, 1 kg/cm² of spray gas pressure gave the most favorable results. And the background of spectral line gave the highest precision as an internal standard.
Mixing sample solution with watermiscible organic solvent, we observed much higher sensitivity. Acetone 50 vol% solution increased sensitivity more than ten times. S/N ratio, however, was not much improved because the background intensity did not decrease as aqueous solution by increasing spray gas pressure. Occasionally, the spectral line was interfered from molecular emission spectrum.

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The solvent extraction and spectrophotometric determination of cobalt (II) with benzoyltrifluoroacetone (BFA) in the presence of tri-n-octylphosphine oxide (TOPO) in cyclohexane were investigated.
The sample solution (pH 5.5 6.0) was shaken with 10^-3M BFA solution containing 10^-2M TOPO. The rapid, complete and quantitative extraction of cobalt (II) up to 20 ppm was performed. The composition of the extracted species was estimated to be Co (BFA)₂TOPO. In the absence of TOPO, however, only traces of cobalt could be extracted. The amount of cobalt (II) was determined by measuring absorbance of cyclohexane solution at 380 mμ or 390 mμ. Molar extinction coefficients were 3700 (380 mμ) and 2300 (390 mμ) Ni (II), Mn (II), Cu (II), Fe (II), citric acid and EDTA interfered.

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A method for the determination of zinc in dust by chelatometric titration after an extraction with TOPO-benzene was presented.
The sample was taken up with hydrochloric acid and hydrogen peroxide. The acid concentration was adjusted to 1.53.0N, and ferric iron was reduced to ferrous by ascorbic acid. Thirty milliliters of the benzene solution of 0.1M TOPO was added, and zinc was extracted by 3 min. shaking. The aqueous layer was separated, and 20 ml of perchloric acid (1 + 15) was added to the organic layer for back-extracting zinc by 1 min. shaking. Hydrogen peroxide, ammonium fluoride and sodium thiosulfate were added to the back-extracted layer for masking, respectively, traces of Fe²⁺, Al³⁺ and Cu²⁺. After the adjustment of pH with hexamine, zinc was titrated with 0.02M EDTA solution by using XO as an indicator. Zinc in dust was determined in 40 min. with sufficienc accuracy and reproducibility.

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X-ray fluorescence method was applied to the determination of iron in phosphate rock. The standard specimens required for the calibration curve were prepared by mixing pure reagents so that the mixture had the average composition (except Fe₂O₃) of phosphate rock, to which was added definite amounts of standard ferric oxide. The iron contents thus determined by the X-ray method, being in the range of 01%, were nearly identical with but slightly higher than those by a colorimetric method.

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The determination of Al₂O₃, FeO and MnO in the isolated slag-inclusion in steel was done by atomic absorption spectrophotometry, in which the inclusion was calcined, decomposed by potassium pyrosulfate and sodium carbonate fusion, made up to volume, and was subjected to the analysis. The method was simple, accurate, efficient and applicable to the practical samples. By the aid of a scale expander, the lower limits of determination were, Al : 0. 1 ppm, Fe : 0.02 ppm and Mn : 0.01 ppm.

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Magnesium in iron usually determined by either extractive, colorimetric or electrolytic method, but the separation of iron as ferric hydroxide is not preferred because of the interefering coprecipitation of magnesium.
The author found that the coprecipitation did not occur at pH 5.56.0 provided that more than 200 mg of silver ion was present with 1 g of iron and 0.11 mg of magnesium, and this fact was applied successfully to the determination of magnesium in cast iron.

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