A simple, rapid and direct determination of degree of polymerization of paraformaldehyde has been attempted by infrared absorption spectroscopy with normal monohydric alcohol homologues as artificial standards. By taking the ratio (R) of the absorption intensity for O-H stretching vibration to C-H stretching vibration. on the ordinate and the ratio (C) of the numbers of OH group to those of carbon in the alcohols on the abscissa, a linear relation was found between R and C for the C values from 3 to 18.
Thus the degree of polymerization was given simply by the I. R. absorption spectra. Mean degree of polymerization determined by the proposed method were about 1020 for some commercial products of paraformaldehyde.

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A rapid and simple method for the determination of small amounts of chloride in water by detector tubes was studied. A detector tube was prepared as follows : silica gel containing silver chromate as a detector reagent was filled in a small diameter glass tube. When 2ml of sample water was injected for five minutes using a syringe the color of the detector reagent was changed from red brown to white depending on the amount of chloride in water, and the length of discolored zone showed the chloride concentration. Measurable concentration of the proposed method is 540 ppm of chloride and the minimum detectable concentration approaches to 1 ppm.
Chloride was determined by the proposed method for a few minutes within a relative error ±10%. Some effects on this method, for example, the inside diameter of the detector tubes, the volume, pH value and the temperature of the sample water, injecting time and the other ions were experimented.
The method was compared with both silver nitrate turbidimetry and mercuric thiocyanate method using river water, well water, rain water and etc. The method agreed with other two methods, and could be comfirmed as a suitable field method.

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A spectrophotometric determination of beryllium using Naphthochrome Green G is presented. The procedure recommended after various fundamental experiments is as follows;
To an aliquot of Be solution (Be : 0.254 μg) in a 25 ml volumetric flask, are added 1ml of 0.2% Naphthochrome Green G (C. I. 44530) alcoholic solution and 1 ml of 1% gelatine solution, and the mixture is diluted to the mark with 1M ammonium acetate buffer solution (pH 5.56.2). The absorbancy of the solution is measured after 1.5 hours at 652 mμ against a reagent blank. Beryllium is determined on a calibration curve prepared with a series of known Be solution.
The molar extinction coefficient was found to be 38, 800.
The method proved to be one of the best for the determination of Be.

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Poirrier Blue C4B, Tropaeolin O, and nitramine are used commonly as indicators for alkali, but they have some disadvantages as, for example, indefinite color changes and instability of colors.
A new indicator, p-nitrophenylhydrazone, proved to be better than those in its stability and its readily observable color change.
General characteristics of p-nitrophenylhydrazone are ;
1. Color change-yellowred
2. pH range-1014
3. pK_a-1212.5
4. Maintainance of stable coloration-more than 1 hour

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The gas chromatography was applied for the qualitative identification of benzyl-, phenoxy-methyl-, phenoxyethyl-, phenoxypropyl-, 2, 6-dimethoxyphenyl-, 5-methyl-3-phenyl-4-isoxazolyl-, and 5-methyl-3-chloropheny1-4-isoxazolyl penicillins. A few mg samples were heated with 2 ml of 20% sodium hydroxide for about 30 min. for their hydrolysis.
The organic acids derived from side chaines were converted to their methyl esters, and gas chromatographically separated using a 1.5 m column of 3.5% SE-30. A connected SE-30 and QF-1 column was also applied for the separation of the esters with closely resembling retention times.

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Qualitative and quantitative analytical methods are presented for the analysis of ortho- and para- nonylphenol isomers. Thin layer chromato-graphy (TLC) using silica-gel can be applied successfully for separations of two-ortho isomers and para-isomer.
Under the conditions used to give good separations on TLC, two ortho-isomers and para-isomer were fractionated quantitatively by elution chromatography. Succeedingly, the fractionated portion of ortho-isomers was further separated into olefine polymers, monoalkylbenzenes and two ortho-isomers by elution chromatography. The authors consider that the differences in the two ortho-isomers are caused by differing character of alkyl groups on the molecules.

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On the determination of residual chlorine in industrial wastes, the following airing method was proposed.
Adjust 50 ml of the sample waste, the chlorine content of which is supposed to be about 2 mg, to pH 1.0 with sulfuric acid, keep in a water bath of 40°C for 40 minutes while airing. Absorb the liberated chlorine carried on the stream of air into the mixture of 0.00564N sodium thiosulfate solution, potassium iodide, acetate buffer (pH, 4.0) and water in two adjacent bottles. After adding the excess of 0.0282N iodine solution to the combined contents in the two bottles, titrate it with 0.00564N sodium thiosulfate solution and determine the absorbed chlorine.
The recovery of chlorine by this airing method was 97%. Coloration and turbidity of the sample or Fe³⁺, Mn²⁺, Cu²⁺ and organic nitrogen compound in it did not interfere with the determination.
The authors also investigated the direct method using iodometry and found that, even in the presence of Cu²⁺, the effect of copper may be minimized by an addition of cyclohexanediamine tetraacetic acid in the sample as a masking agent or by a removal of copper using Amberlite IR 120 prior to the titration.

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Zinc 8-hydroxyquinaldate precipitates prepared by the conventional and the PFHS methods were investigated by means of the electron microscope. The precipitated compounds have one mole of water of crystallization, the formula being Zn(C₁₀H₈ON)₂·H₂O. The crystals belong to the orthorhombic system. They are thin plates with predominant (010) faces.
By heating the particles in an oven or in an electron microscope the crystal is dehydrated and the crystal structure is changed. But when a few crystals mounted on the specimen support grid for electron microscope are heated at 130°C for a long time in an oven, they show the same diffraction pattern as that of the original hydrated crystals.

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The paper electrophoresis of twenty water soluble coal tar dyes permitted for food was studied by the Whatman No. 1 filter paper immersed in n-hexane as a cooling agent, with twelve electrolytic solutions at pH 3.011.6, under the conditions of 3, 000 volts and 30 minutes migration. The spot forms and the migration distances were largely influenced by the pH of the electrolytic solutions, and could be classified into several groups by the chemical constitutions of the dyes.
The selection of suitable electrolytic solutions enabled the identification of the twenty water soluble coal tar dyes and also the discrimination of the main and the subsequent dyes.

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Various factors in gas-chromatographic analysis of tobacco alkaloids, including sort and amount of stationary liquid, column temperature, flow rate, sort and grain size of solid support, were examined on their influences on the height of theoretical plates and the sensitivity of determination, and the operating conditions in the separation of nicotine homologues of analogous properties were investigated.
The height of theoretical plates was minimized on a definite flow rate (ca. 100 ml/min.), and the value decreased hence the column efficiency increased with increasing amount of stationary liquid (PEG 6000) provided that its amount was 324%. With the flow rate minimizing the height of theoretical plates, the latter showed a minimum at 160180°C of column temperature. C 22 is preferred to Celite as a solid support, and the smaller particles were more preferable. The amount of sample to be injected should be smaller to obtain the largest number of theoretical plates.
The recommended conditions for the separation of nornicotine and myosmine were as follows: the amount of stationary liquid 24%, temperature 180°C, flow rate 80 ml/min., injected amount 1 μl and column length 2 m.

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The reaction between antimony (III), (V) chloride and thiooxine (8-mercaptoquinoline) in aqueous and nonaqueous media was investigated, and the formulas of complexes were determined by the conductimetry and the amounts of Cl, S and Sb in the compounds. Pentachloride precipitated -with the reagent as R₂H₃SbCl₆ in dichloromethane, as RH₂SbCl in conc. HCl, and as RSbCl₄ in glacial acetic acid.
Trichloride formed RH₂SbCl₄ in benzene, RSbCl₂ in dil. HCl, and RHSbCl₃ in glacial acetic acid. Antimony pentachloride gave chloro-complex ion SbCl₆^- in nonaqueous or conc. HCl solution, but is hydrolyzed to [Sb (OH)_xCl_6-x]^- in dil. HCl after a few hours and was not precipitated with the reagent. On the contrary, antimony trichloride was precipitated in dil. HCl, but was not in conc. HCl.
The gravimetric separation of Sb (III) and Sb (V) using conc. and dil. HCl gave good results.

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Ranges of color change of some pH indicators in the mixed solvents were determined by drawing their ideal pH-absorbance curves using the equation Y=2-log{(1-X)/X} as 0.01≤X≤0.99.
Ranges of color change became generally narrower as the concentration of organic solvent increased, pH scale 2.08 (40%) thus diminishing to 1.87 (80%) in methanolic dimethyl yellow (D. Y.) solution and 1.72 (40%) to 1.66 (80%) in methanolic bromcresol green (B. C. G.) solution. Color change points of mixed indicators were obtained by overlapping the curves of any two component indicators, where the curves were corrected by color responsibility of naked eyes.
The color change points of mixed indicators were moved by change in their mixing ratios. In some cases the selection of an appropriate mixing ratio enabled the color change on a disired pH adjacent to the usual color change point of mixed indicator. Thus, color change point 5.1 (Methyl Red : B. C. G. =1 : 3 usually) changed to 4.7 (1 : 6) and 3.3 (D. Y.: Methylene Blue =1 : 1 usually) changed to 2.7 (1 : 1.5).
These new ratios were decided geometrically by overlapped curves. Good results were obtained in the automatic colorimetric titration by using filters of colored solution under the pH condition of the usual color change point in a water medium.

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[in Japanese]

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