It is necessary to systematize the data of relative retention values in order to make an easier application of gas chromatography. Therefore, the effect of varying the kind of support and the amount of liquid used in the stationary phase on the relative retention values has been investigated.
The experimental results indicated clearly that the change in relative retention value caused by the kind of support and by the amount of liquid used in the stationary phase must be taken into consideration. That is, there is almost no change in relative retention value induced by a change in the kind of support in the case of nonpolar substances, such as hydrocarbons; but there is a considerable change in relative retention value produced by changing the kind of support in the case of polar substances, such as water, alcohol, amine, ketone, and aldehyde. Also, it was found that there was a considerable change in relative retention value effected by a change in the amount of liquid used in the stationary phase in the case of polar substances.
The extent of such change depended too on the kind of liquid used in the stationary phase, but, for systematizing the data of relative retention values it was found necessary to consider also the kind of support and the amount of liquid used in the stationary phase.

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The experimental results in the preceeding report indicated that, using as a support celite-545, and using as the liquid in the stationary phase 20% or more by weight of paraffin in the case of a paraffin column, and 10% or more by weight of polyethylene glycol in the case of a polyethylene glycol colum, a definite relative retention value could be observed for each substance used. Based on this result, the present study was carried out by preparing a paraffin column, a dinonylphthalate column, and a polyethylene-glycol column, using celite-545 as a support with 33% liquid in the solid phase; and the relative retention values of 60 kinds of substances were determined. These were then compared with known data in the literature.
The relative retention values determined by the authors showed good agreement with the data of A. T. James and E. R. Adlard. Also, the dinonylphthalate column data agreed with the data of G. T. Pierotti, but there was no agreement with those of T. H. Purnell and D. W. Grant.
These results indicated that the experimental conditions employed by the authors, were similar to those of A. T. James, E. R. Adlard, and G. T. Pierotti; but different from those of T. H. Purnell and D. W. Grant in some respect which was unnoticed. It can be concluded that more and more data of relative retention values should be published so that their comparisons can be made.

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Quercetinsulfonic acid is soluble in water, and its neutral solution forms a brown colored watersoluble complex with uranium ion. Therefore, the fundamental conditions for the determination of uranium by this method have been investigated. Uranyl-quercetinsulfonate complex shows comparatively wide absorption band with a maximum absorption at around 460 mμ. The complex when colored at pH 6.07.5, gives a difinite absorbancy; however, the absorption by the reagent itself is rapidly increased with pH above 6.5. For this reason, it is necessary to adjust the solution to pH 6.06.5 in the case of quantitative determination. The reagent with concentration above 2.4×10^-4 mol/l gives a definite absorbancy. Therefore, the determination can be carried out well by adjusting the reagent to 4.8×10^-4 mol/l and pH to 6.06.5. The calibration curve was prepared by using 112.5 γ/ml at 460490mμ; it followed Beer's law well and its molecular extinction coefficient was 17, 600. Good results were obtained for quantitative determination after removing coexisting elements with TBP. When thorium is present in an amount about the same as that of uranium, about 0.005% EDTA should be added at the development of coloration. Or, when a large amount of thorium is present, is separated by extracting it with TBP from 7N HCl solution before the color is developed.

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Beeghly's method for the determination of aluminum nitride in steel consists of, first, determining experimentally the soluble nitrogen in the ester-halogen treated residue, and secondly, calculating the aluminum equivalent to that nitrogen without any experimental estimation. This method has a tendency to lead to erroneous results, because some of the other nitrides coexisting in the sample behave just like aluminum nitride all through the procedure.
In order to clarify whether this suspicion is reasonable or not, the author synthesized nitrides of some elements ordinarily found in plain carbon steel such as iron, manganese, silicon, and chromium, as well as aluminum, and compared the behavior of these synthesized nitrides, treating them with such halogenated solvents as methanolic bromine (stirred at room temperature and 60°C) and methanolic iodine (stirred at room temperature and 60°C) as well as ester halogen (at boiling temperature).
The results of these treatments showed that iron nitrides do not interfere because they are dissolved in ester halogen and methanolic bromine; and that the interference by nitrides of manganese is not so great; but that nitrides of chromium, especially the one in the formula of Cr₂N, interfere nearly 100 per cent, as can be seen in the column in Table III. Although nitrides of silicon seem to interfere little, the samples here synthesized are likely to be solid solutions of nitrogen with silicon, as can be seen in Table II, and not nitrides of silicon with a fixed formula such as SiN, Si₂N₃, or Si₃N₄; hence the behavior of nitrides of silicon can not be ascertained from this experiment. Moreover, it is interesting to observe from the same table that the so-called insoluble nitrogen in these synthesized nitrides is apt to be directly dissolved with these halogenated solvents or, at least, to become feasibly soluble with dilute acid after being treated with them.

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From the results of a preliminary study it is known that there is at least a possibility that the determination of aluminum nitride in steel is interfered with, possibly led rather to positive errors, by coexisting nitrides, if the procedure is carried out according to Beeghly's ester halogen method. Hence, not only the nitrogen but also the aluminum in the ester-halogen treated residue should be estimated. Moreover, it is better that the aluminum as well as the nitrogen in the ester halogen filtrate be determined, because esterhalogen soluble nitrogen is not always included entirely in the so-called acid-soluble nitrogen, as can be assumed from the results of the preliminary study. But as the ester halogen in the filtrate is difficult to remove by means of evaporation, after being acidified with sulfuric acid, to the extent of not interfering with nesslerization, the ester halogen technique has to be given up.
As the result of further studies, the recommended procedure was decided as follows : onegram sample of steel is stirred for 2 hours at room temperature in a mixture of 4 to 5 ml of bromine and 50 to 100 ml of methanol in the dissolving apparatus (Fig. 2). This is then filtered through filter paper previously treated with hot dilute sulfuric acid, water, then methanol. The residue, after being dried for one hour at 105°C, is treated with dilute sulfuric acid for 2 hours together with the filter paper, and made up to some 150 ml of 1N sodium hydroxide solution, then distillated at low temperature under reduced pressure (Fig. 2 and 3) to avoid the contamination of aluminum from the wall of the distillation flask. The distillate is estimated for nitrogen photometrically after nesslerization; and the aluminum in the remaining solution in the flask is determined photometrically after being oxinated and extracted with benzene. The filtrate, on the other hand, after being acidified with sulfuric acid, is evaporated to dryness with the help of suction (Fig. 4), and extracted with water, made up to some 150 ml of 1N sodium hydroxide solution, followed by distillation under reduced pressure; the resultant distillate and remaining solution in the distillation flask are then utilized for the estimation of nitrogen and aluminum, respectively, as above.

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In the volumetric determination of calcium in limestone with permanganate titration, the various conditions have been studied for a method without the separation processes of co-existing elements such as dehydration of silica and reprecipitation of calcium oxalate. The results obtained can be summarized as follows:
(1) On the washing of the precipitate of calcium oxalate, it was found that the diffrence between the use of ice cold water (05°C) and water of normal temperature (21°C) was very little, and satisfactory results were given by washing 8 to 14 times using 10 ml of water each time. When washing was done with hot water (70±5°C), the titration results were scattered.
(2) Among the filter paper used in the investigation, it was found that Toyo Filter Paper No 5B or a paper with similar texture was suitable, but Toyo Filter Paper No. 5A, a rapid filtering paper of loose texture, required a greater number of washings.
(3) After washing the precipitate, satisfactory results were obtained by the following procedure: transfer the precipitate to a beaker and dissolve it in dilute sulfuric acid. After the titration with permanganate, add the paper used in filtration to the solution, and continue the titration to obtain the true end point.
(4) The effect of co-existing elements of amounts such as are involved in ordinary limestone was not great even without reprecipitating treatment.
(5) Ignition treatment of the sample to destroy organic matter and to render the calcium in the siliceous material more easily soluble in acid was practically unnecessary for the samples tested.

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An automatic continuous coulometric titrator has been constructed consisting of electrolysis and titration cell, sensor electrodes for end point detection, D. C. source for electrolysis and its control system, recorder and electrolyte reservoir. The sample solution and electrolyte are poured into the titration cell with a constant flow rate by means of a pump driven by a synchronous motor, and the sample solution is titrated with electrolytically generated reagent. The D. C. current for electrolysis is so controlled that the mixture of the sample and said reagent in the titration cell is maintained at a definite state, namely the ordinary equivalent point of the reaction. The control is achieved by an electronic automatic zero balancing system.
Using this titrator, the concentration of sulfuric acid is measured and compared with the theoretical value. Sodium sulfate contained in the sample solution gives no interference in the determination of sulfuric acid.
Variations in the temperature in the electrolysis and titration cell, and in the frequency of the electric source, cause errors in metasurement, and therefore, compensation for these effects was investigated.

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In order to determine the boron in silicates, a mixture of Na₂CO₃ and ZnO was used as a decomposing agent. When the samples were heated with this decomposing agent, the silica in the samples was almost perfectly converted to a compound which was insoluble in water, and so the silica was easily separated from the soluble matter. The method for the determination of the boron based on this decomposition was tested and the following results were obtained. (1) Using a 2: 1 mixture of Na₂CO₃ and ZnO as the decomposing agent, the samples were perfectly decomposed at a temperature of 900°C for 10 minutes. (2) The quantities of silica which dissolved out of the decomposition product with boron varied according to the boron content of the samples, the more boron, the less silica dissolved. (3) The precision of this method was about 1% average deviation. (4) The time required for the determination was less than 2 hours.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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