A large number of methods has been reported on the correction for matrix effect in fluorescent X-ray analysis of high-alloy steels, but many of them require very complicate calculations or a great number of standard samples.
The method proposed here by the authors utilizes mass absorption coefficients and even a large number of correction factors are transformed into only two. Since a correction formula is readily obtained by relatively small number of standard samples and simple calculations, an accurate analytical value is easily obtained. The standard errors in estimation of chromium after corrections are 0.13% on tool steels, 0.10% on high temp. steels, and 0.14% on stainless steels.

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A rapid determination of trace of chloromethanes in hydrochloric acid produced by thermo-chlorination of methane was studied.
Carbon disulfide was added to the 500 ml of sample hydrochloric acid and the mixture was shaken vigorously for about 10 minutes. The extracted chloromethanes (methylene chloride, chloroform, and carbon tetrachloride) together with the solvent (carbon disulfide) were subjected to the gas chromatography.
The amount of carbon disulfide to be added and the coefficient of extraction under various conditions were determined experimentally. The gas chromatographic conditions were : a thermal conductivity type detector. Carbowax-6000 column at 80°C, and carrier gas helium 50 ml/min.
The lower limits of determination were : methylene chloride 10 ppm, chloroform 5 ppm and carbon tetrachloride 1 ppm. The time required (1.5 hours), the precision and the accuracy of this method were satisfactory for routine work in the factory.
A considerable increase in sensitivity of determination was obtained when a hydrogen flame ionization detector was used in place of a thermal conductivity detector. The gas chromatographic conditions for this case were : a hydrogen flame ionization detector, DOP+Carbowax-6000 column at 70°C, carrier gas nitrogen 45 ml/min, and range×sens.0.4 1.6×10³10⁴. The lower limits of determination were diminished to 0.04 ppm for methylene chloride, to 0.04ppm for chloroform, and to 0.02 ppm for carbon tetrachloride, respectively, without an increase in the time required for an analysis.

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Rapid oxidation of 0.5 to 2 mg organic samples by a flow combustion furnace has been investigated in order to improve the rapidity of the method for carbon-hydrogen microdetermination.
The diffusion process of a pulse fuel gas injected into a stream of gaseous oxygen was first observed by utilizing the rapid response of the color change of zinc chromite powder to the oxidation-reduction reaction at ca. 500°C. It was verified from the observation that not only a catalyst but also an oxidizing reagent were necessary to oxidize such a pulse sample even in a stream of oxygen because of an incomplete mixing of the sample gas with oxygen.
A copper-chromium oxide mixture was found to be much more superior as an oxidizing reagent in both the activity and the stability, which was supported by the X-ray diffraction and the life test. A flash combustion method using an aluminum foil capsule as a priming was developed for the instanteneous combustion of a solid sample.
Connecting the flash combustion furnace with a contact oxidation furnace, minor quantity of organic samples in any state was successfully oxidized in a short contact time of less than 11 sec.

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The solvent extraction of vanadium (V) with 3-hydroxyflavone and absorption spectra of the complexes formed in organic phase have been studied for the determination of vanadium(V).
The extraction with chloroform as an extractive solvent gives a complex (acid-type complex) having an absorption maximum at 560 mμ with a constant absorbance in the pH range from 3.0 to 4.0. The molar ratio of vanadium(V) to 3-hydroxyflavone in the acid-type complex is estimated to be 1 to 2. The extraction with chloroform containing ethyl alcohol gives another complex which has an absorption maximum at 480 mμ with a constant absorbance in the pH range from 2.8 to 4.5. The latter complex is shown to be an ester formed by the reaction of the acid-type complex with ethyl alcohol in the molar ratio of 1 to 1. For both complexes, Beer's law is obeyed at least up to 1.0 × 10^-4M vanadium(V) in chloroform. The molar extinction coefficients of the acid-type and of the ester-type complexes are 4900 and 5550, respectively. The effect of diverse ions in also examined.

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It has been found that Calcichrome forms complexes with nickel(II) and an attempt has been made to test the applicability of Calcichrome as a reagent for the spectrophotometric determination of nickel. Nickel (II) forms two kinds of complexes with Calcichrome in an alkaline medium. One of them is a 1 to 1 (metal to dye) complex formed at pH below 12 (complex I), and the other is a 1 to 2 complex obtained at about pH 13 (complex II). The absorption maximum of the former is at about 550 mμ, and that of the latter at about 585 mμ. If the pH of the solution is adjusted to a fixed value in the neighborhood of 11.5 or of 13.0, and the absorbance measurements are made, respectively, at about 615 or 625 mμ where difference in absorbance between the reagent and the metal complex is the largest, Calcichrome is a useful reagent for nickel. In this case, a linear relationship was maintained between the concentration of nickel and the absorbance. The molar extinction coefficients of the complexes I and II were 6900 and 15000, and their sensitivities were 8.5 × 10^-3 and 3.9 × 10^-3 μg Ni/cm² for log(I₀/I) =0.001, respectively. Metals including calcium, magnesium, copper, cobalt, manganese, iron, aluminum, , titanium, and vanadium interfere with the determination.

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It has been found that Calcichrome forms two kinds of complexes with cobalt(II) and an attempt has been made to test the applicability of Calcichrome as a reagent for the spectrophotometric determination of cobalt. The compositions of the cobalt(II)-Calcichrome complexes were 1 to 1 at about pH below 10 (complex I) and 1 to 2 at about pH above 11 (complex II). The absorption maximum of the complex I is at 550 mμ, and that of the complex II at 520 mμ. If the pH of the solution is adjusted to a fixed value in the neighborhood of 9.9 or 12.0 and the absorbance measurements are made at about 580 mμ or 595 mμ, Calcichrome is a useful reagent for cobalt. A linear relationship was maintained, in this case, between the concentration of cobalt and the absorbance. The molar extinction coefficients of the complexes I and II under the conditions recommended were about 15000 and 32000, and the sensitivities were 3.9 × 10^-3 and 1.8 × 10^-3 μg Co/cm² for log(I₀/I) =0.001, respectively. Metals including calcium, magnesium, copper, nickel, manganese, iron, aluminum, titanium, and vanadium interfered with the determination.

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Many papers have been presented on the gas chromatographic analysis of mixtures of inorganic gases and gaseous hydrocarbons, such as town gas, cracked petroleum gas or natural gases, but almost all the methods recommended require two or more columns. The authors have investigated the possibility on gas chromatographic separation of all the components on only one column by the stepwise programming of column temperature.
The column bath was cooled with dry ice. A sample was injected when the column temperature reached -75°C. Immediately after the elution of the concerted component, the column was taken out of the bath and was directly electrified. The column temperature reached its equilibrium in about 10 minutes (see Fig. 6). The flow rate of carrier gas was controlled by constant pressure method.
Activated alumina coated with Carbowax 20M (7090 mesh, 2%) and Porapak-Q showed better separations than silica gel and activated charcoal. By the use of activated alumina coated with Carbowax 20M, H₂, O₂, N₂, CO, CH₄, C₂H₆, C₂H₄, C₃H₈, iso-C₄H₁₀ and n-C₄H₁₀ were separated within 15 minutes; in the same manner by the use of Porapak-Q, H₂, N₂, O₂, CO, CH₄, CO₂, C₂H₄, C₂H₆, C₃H₈, iso-C₄H₁₀ and n-C₄H₁₀ were separated within 15 minutes (see Fig. 7). The repeatability and the linearity on sample size vs. peak area in this method were good as shown in Table II and Fig. 8.

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Determination of terephthalaldehydic acid (TAA) in terephthalic acid (TPA) with the Tollen's reagent was investigated, whereby 100 mg of TPA added with a known amount of TAA was weighed out into a small glass vessel and 3 ml of the Tollen's reagent was added to be dissolved completely. A sheet of filter paper was placed under the vessel, and the per cent reflectance at 440 mμ was measured at 1213 minutes after the addition of the reagent against water in a similar vessel on a filter paper. In this case the following equation held between the concentration (C) of TAA and the percent reflectance (R),
C=α(100-R/R-10)
where α is a constant.
This fact provides a calibration line and the silver mirror procedure hitherto been used only qualitatively has been quantitized. The results by the proposed method agreed well with those by polarography, and the procedure was much simpler in the proposed method. An analysis required less than 20 minutes, and the lower limit of determination of TAA was about 0.005%.

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Ordinary pyrolysis (pyrolysis in a sealed glass tube) and pyrolysis gas chromatography of alkylpyridinium salts with a long chain alkyl group, such as cetylpyridinium bromide, laurylpyridinium bromide etc. were carried out. Pyridine, alkyl halide and α-olefine were obtained by usual pyrolysis, whereas pyridine and alkylhalide were detected by pyrolysis gas chromatography. Ladenburg rearrangement did not take place in both cases. Based upon these facts, qualitative and quantitative analysis of alkylpyridinium salts was devised with the peak of alkyl halide. The mechanism of pyrolysis was also discussed.

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In the mass spectrum of pure oxygen, peaks which do not belong to those based on oxygen itself were observed at M/e=12, 14, 28 and 44. These peaks were believed to be attributed to carbon monoxide and carbon dioxide formed by oxygen decarbiding the tungsten filaments in the ion source and ionization vacuum gage.
Because the spectrum of oxygen contributes to the spectra of impurities, it is difficult to determine small amounts of impurities in oxygen by a mass spectrometer without concentrating impurities. Therefore, highly pure oxygen was analyzed by a mass spectrometric measurement of residual gases after absorption of oxygen with metallic copper (700°C) using helium as the internal standard. Nitrogen, 0.020.2%, and argon, 0.010.4%, were found in commercial compressed oxygen.

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The influence of various acids and coexisting ions upon precipitation of metallic arsenic obtained by reducing with stannous chloride in the determination of arsenic in iron and steels has been investigated in detail.
The interference from the acid concentration and diverse ions is little when the sample is decomposed with sulfuric acid, hydrochloric acid, phosphoric acid and hydrogen peroxide. Subsequently, the method can be applied to almost all sorts of samples and the analytical results are satisfactory.
When the sample is decomposed with nitric acid which is, subsequently, removed by heating to white fumes with perchloric acid or sulfuric acid, the analytical value becomes lower by the interference from perchloric or sulfuric acid. Especially, titanium, vanadium and molybdenum interfere seriously in the perchloric acid method.
Besides, it has been found impossible to precipitate less than 0.005 per cent arsenic in iron and steels completely as metallic arsenic by means of the stannous chloride reduction.

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Synergistic effect of pyridine(py) on the extraction of manganese(II) with 2-thenoyltrifluoroacetone(TTA) was found to be attributable to the formation of an adduct, Mn T₂py₂. Using the extractability of this adduct into organic phase, a spectrophotometric method for separation and determination of manganese(II) was established.
The pH of a sample solution containing 20 to 800 μg of Mn(II) was adjusted to about 5. After the addition of pyridine and TTA-benzene solution, manganese was extracted into benzene and the absorbance of the organic phase was measured at 430 mμ. The sensitivity of this method corresponding to an absorbance of 0.01 was 2 ppm of Mn(II) in the organic phase. Interference from chromium (III) and copper(II) could be eliminated by converting them into phosphate and cuprous iodide, respectively. The method was applied to the analysis of manganese(0.22%) in steel samples.

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Atomic absorption spectrophotometry was applied to the determination of small amounts of Aluminum in steel used nitrous oxide and acetylene flame.
The results obtained was that the calibration curve was quite linear for 0.55 ppm aluminum in hydrochloric acid in the presense of 1% iron.
When the method was employed to the analysis for experimentary samples (standard), the results was found to be satisfactory both accuracy and precision at least up to 0.005% aluminum.

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