The deposition of silver on a solid electrode by chronopotentiometry and voltammetry with linearly varing potential was investigated by using carbon paste electrode or platinum disk electrode. Since the usable potential range of the carbon paste electrode in Britton Robinson buffer solution is limited by the decomposition potentials of water, the effect of pH of the buffer solution was studied. It was recognized that the iR drop in the electrode itself affected the shape of the chronopotentiogram and its transition time. The transition time constants were determined within a relative error of ±3%. The plot of log (√τ-√t)/√τ vs. potential (vs. SCE) was linear with the reciprocal slope 79 mV. The ratio of transition time for the cathodi. scan (τ_c) and that for the anodic scan (τ_a) was aboet 1. The transition time constants were almost independent of the current densities.
Silver ion in the range of 0.01 to 0.08 mM is determined sucessfully in 0.1 or 1 M potassium nitrate solution referring to a calibration curve, although the theoretical value of the peak current of silver ion by the Voltammetry with linearly varing potential did not accord with the experimental values, because the aging effect on the activity of the deposited silver was not known.

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The color and transparence of polymer chips are usually estimated by visual inspection and methods of their quantitative measurement have not been given. Widely used JIS method (CIE method) for representing colors is inconvenient for the sensory interpretation.
The authors have presented a method of quantitative estimation of color and transparence of polymer chips by reflectometry. In the proposed method, chips of sample polymer 12 mm in diameter and 515 mm in length are placed in a sample dish with a sheet of white or black paper on its bottom, and they are irradiated vertically. The scattered light from the polymer chips was collected and its intensity was measured at 445 mμ, 555 mμ and 600 mp to obtain reflection rates. Simple calculations give the color (c) and transparenc (T) of polymer chips.
The proposed method is rapid and simple, and has an advantage in its feasibility to the quick appreciation of the result. The time required for a measurement is about 20 min., and the accuracy is satisfactorily high.

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A rapid non-destructive method based on the slowingdown process of neutrons by hydrogen nucleus was investigated for determination of hydrogen content in organic solvent. Fast neutrons from an Am-Be neutron source were moderated by the sample to thermal neutrons, which were then measured by a BF₃-counter. The logarithm of the counting rate was found to be directly proportional to the content of hydrogen in the range60120 mg/ml using 50 ml sample. The immersion-arrangement was suitable for this determination and some graphite-blocks were used effectively as the thermal neutron reflector. The influence of co existing carbon and oxygen content upon the calibration curve was not perceptible. The application of the method into the range of lower hydrogen content, such as 0100 mg/ml, was also examined.

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A method for the spectrophotometric determination of 0.52.5% lithium in silver filler alloys with thorin was investigated.
The main metallic components and influencing metals were preliminarily removed by electrolysis of the sample solution in 0.4 N sulfuric acid using mercury cathode. This solution was transferred to a 100 ml measuring flask, its pH was adjusted to about 5.0 with potassium hydroxide solut, un, and then diluted to 100 ml. A 5 ml aliquot of this solution was taken into a 10 ml measuring flask, to which were added 0.5 ml of 20% potassium hydroxide solution and 1.0 ml of 0.2% thorin solution, and it was made up to 10 ml with water.
The absorbance at 456 mμ was measured against the reagent blank.
The results of recovery tests on synthetic samples were quite satisfactory.

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The infrared absorption spectra of equilibrium mixtures of nitrogen dioxide and dinitrogen tetraoxide were observed under various pressures and temperatures. In order to secure a temperature homogeneity in the cell, it was placed wholly in an air bath which was provided with heaters, a fan and a regulator.
The band at 1617 cm^-1 of nitrogen dioxide and the bands at 1735 cm^-1 and 1255 cm^-1 of dinitrogen tetraoxide were used as key bands. From the integrated intensities of these key bands, the partial pressures of both species, P_m(of NO₂) and P_d(of N₂O₄), were obtained, and the equilibrium constants K's in various temperatures were calculated as P²_m/P_d. Although the calculation of K's seemed not to be sufficiently accurate the plotting of log K versus 1/T made a fairly good straight line, and from its gradient has been obtained the dissociation heat of dinitrogen tetraoxide as 17.5 kcal/mol.

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Optimum conditions for extraction of a conjugate complex alizarin complexone-lanthanum-fluoride by organic solvent containing amine were investigated and a method of determination of micro amount of fluoride has been established.
To a sample solution in a separatory funnel are added with shaking alizarin complexone solution, a buffer solution of pH 4.4, acetone, and lanthanum chloride solution. It is extracted with 10 ml of 5 vol% N, N-diethylaniline solution in iso-amyl alcohol, and absorbance is measured using a 575 mμ filter.
The results of analysis on 5 μg fluoride were: variation coefficient 1.47%, molar extinction coefficient 23, 500, and absorbance of blank solution 0.06 with 10 mm cell. The method has been applied to the determination of micro amount of fluoride in drinking water with satisfactory results. Ions usually present in drinking water did not interfere.

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A spectrophotometric method for the estimation of Cellocidin, acetylenedicarboxamide, based on the addition of ammonia to it was presented. Two hundred milligrams of 10% wet table powder was weighed into a 500 ml volumetric flask, and 400 ml of water and 5 ml of 1 N hydrochloric acid were added. The flask was warmed for 10 minutes with occasional shakings in a water bath held at about 70°C and allowed to cool. The suspension was made up to 500 ml with water and filtered through a dry filter paper. A 5 ml portion ofthe filtrate was pipeted into a 100 ml Erlenmeyer flask and 5 ml of 1.2 N ammonia water was added. The flask was connected with a Liebig condenser and placed for 20 minutes on a boiling water bath. After standing to cool, the content of the flask was transfered into a 50 ml volumetric flask and made up to 50 ml with water. The absorbancy of the solution at 296 mμ was measured using a cell with 10 mm width. The “blank” obtained by the way mentioned below was subtracted from the absorbancy, and the amount of Cellocidin was calculated from the calibration curve prepared by treating the standard solution containing 80400 μg of Cellocidin through the whole procedure.
“The blank” : Five ml of the filtrate of the sample suspension was pipeted into a 50 ml volumetric flask.Forty of water and 5 ml of 1.2 N ammonia water were added and it was immediately made up to 50 ml with water. Within two minutes after the addition of ammonia, the absorbancy of the solution at 296 mμ was measured.
The raw materials and by-products of the Cellocidin synthesis did not interfere with the analysis. The method was applicable to the analysis of the formulations containing other fungicides, phenylmercuric acetate or dithianone.
The compound obtained by treating Cellocidin with ammonia was identified with 1-amino-1, 2-ethylenedicarboxamide by IR and UV spectra.

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Polarographic determination of saturated aliphatic aldehydes in aqueous solution was attempted by use of following four compounds: methyl-, isopropyl-and tert-butyl hydroxylamines and α-hydroxyaminovaleronitrile.
(i) Satisfactory results were not obtained by methyl-and tert-butyl hydroxylamines.
(ii) Isopropyl hydroxylamine in its concentration 1.5 × 10^-1 M showed a linear relation between the wave height developed and aldehyde concentration of about 10^-510-3M at pH 3.04.0 Less than 10^-2 M of ketones did not interfere.
(iii) α-Hydroxyaminovaleronitrile in its concentration 1.0 × 10^-1 M showed a linear relation between. the wave height developed and aldehyde concentration of about 10^-410^-3 M at pH 5.06.0. The interference from ketones became serious when its amount excedes several times of the aldehyde concentration, and separatory determination was difficult. The results were compared with that by Girard T reagent.

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A method for the detection of carboxylate ions in the effluent from the ion exchange chromatographic column was established. Sodium chloride solutions containing either hydrochloric acid, sodium hydroxide or cationic buffer such as diethylenetriamine were used as eluents. The effluent from the chromatographic column was successively led to a “buffer apprehending column” to remove cationic components of the buffers and to bring the pH to almost neutral. The effluent from the latter column was mixed with a bromophenol blue solution, and then the transmittance at 570 mμ was measured with automatic recordings.
Anion exchange resin, Dowex 1 × 8 chloride, was used for the chromatographic column, and cation exchange resin, Amberlite XE-64 and Dowex 50W × 8, were used for the buffer apprehending column.
About 10^-6 mole of carboxylate ion was detected. Quantitative determination was not successful, however, because of non-linearity in color development and instability of the indicator solution.

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A submicromethod for the determination of alkoxyl groups is described. This is a modification of the micromethod previously reported by this author. In the proposed method, a sample (0.30.5 mg) is weighed in a platinum boat by means of a micro balance and heated with hydriodic acid in a reaction flask. The alkyl iodide formed is burned into iodine. The iodine is absorbed by a silver plate and weighed. The errors that may appear in this method are minimized. The standard deviation is 0.21% (for CH₃O) or 0.25% (for C₂H₅O). This submicromethod can be carried out with the same apparatus for the previous micromethod except for the combustion tube reduced to mm in its inside diameter.

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The analysis of alkylsulfate (ASNa) in detergent powders involving ASNa and sodium dodecylbenzene sulfonate (ABSNa) as main constituents was studied by means of an infrared spectroscopy (IR) after an extraction with 90% ethanol. Potassium bromide disk method was successfully applied. Quantitative analysis with sulfuric acid hydrolysis was also studied.
ASNa was detected by its characteristic absorption bands at 1085 cm ^-1and about 1000 cm^-1, and the limit of detection was 10%. The amount of ASNa was determined by measuring the extinction quotient [1085 cm^-1/(1085 cm^-1+1045 cm ^-1)], but selection of the base line had been very difficult. The recommended procedure among various ways studied was as follows. When the content of ASNa is less than about 40%, the base line is drawn parallel to the 0% line from the point of absorption at 1030 cm^-1, and when the content is more than about 40%, the base line is drawn through the points of absorption at 1110 cm^-1 and 1030 cm^-1. The standard deviations in the quantitative analysis of ASNa were 1.81% and 1.76% for the IR method and the hydrolysis method, respectively.

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A new method for the spectrophotometric determination of beryllium was studied, using Pontacyl Violet 4BSN (Color index 16580) as a reagent. Berylliumreacted with the reagent at pH 6.57.4 to form a colored complex having an absorption maximum at 620 mμ, which can be used for the determination of beryllium. Beer's law was followed up to 0.3 ppm of beryllium and the molar extinction coefficient was 24, 600 at 620 mμ in 10% (v/v) acetone solution. Aluminum, iron(III), copper(II), chromium(III), scandium and phosphate interfered with the determination of beryllium. The addition of 10% of acetone increased the sensitivity of the reagent on beryllium, and it reduced the interfering effects of aluminum, scandium, iron(III) and nickel when determining beryllium.

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Conductometric determination of microamount (0.5 30 ppm) of carbon in iron and steel was studied. The carbon dioxide produced by heating samples in a purified oxygen current was absorbed in 150 ml of 1.2 × 10^-3N barium hydroxide solution containing 2 g of barium carbonate, and the change of the conductivity (2.042.16 m±Ω) of the solution, kept at 43.6 ± 0.01°C, was measured.
As the standard of carbon, 01.00 ml of sodium oxalate solution (50.2 mg Na₂C₂O₄/l) was placed in a quartz crucible, heated to dryness at 280°C, and decomposed in the furnace to produce carbon dioxide at about 900°C. In order to minimize the blank value, zirconia, beryllia, quartz, and various porcelein crucibles were compared and the porcelein (SiO₂ 90%, Al₂O₃ 7%) crucible was recommended to be adequate for this purpose.

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According to the Methylene Blue-dichloroethane absorptiometric method for the determination ofmicroamounts of boron in iron and steel, as the blank value was high and inconstant, the method has been improved by adding a process of washing with water as follows:
Two tenths gram of sample is dissolved in 5 ml of 5N sulfuric acid and 2 ml of hydrogen peroxide (30%) in platinum crucible and an excess of hydrogen peroxide is decomposed by heating. After cooled, the residue is filtered off with a closed texture paper and polyethylene funnel, and washed with water. The filtrate is collected in a polyethylene beaker, diluted with water to about 20 ml and to it is added 5 ml of hydrofluoric acid (5%). After about one hour, the mixture is placed in polyethylene separatory funnel, diluted with water to about 50 ml, added with 3 ml of Methylene Blue solution (0.001M) and 25.0 ml of dichloroethane, and it is shaken vigorously for about one min. After being kept standing, the lower layer separated is placed in another polyethylene separatory funnel, and is added with 10 ml of water, and it is shaken vigorously for about 2 min. After the keep standing, the lower layer separated is filtered of through a dry paper and the absorbance is measured at 660 mμ against water.
The residue is fused with sodium carbonate and extracted with 5 ml of 5N sulfuric acid in a polyethylene beaker, followed by the above procedure. If chromium is remained in the residue, 2ml of ammonium ferrous sulfate solution (4%) should be added, prior to the addition of Methylene Blue solution.

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It is known that ferrochromium of lower carbon is usually decomposed with perchloric acid, and that the one of middle and higher carbon is acidified with nitric acid after it is decomposed habitually with sodium peroxide. The acidity is then adjusted to reduce chromium by adding sodium hydrogen sulfite and to it was added ammonium molybdate immediately. The solution was extracted with a solvent mixture (n-butanol + chloroform) to separate phosphomolybdic acid and to the extract stannous chloride was added for the reduction. The absorbance of the molybdenum blue produced were measured at a wavelength of around 700 mμ to determine the phosphorous content. The operation period of time was found to take 60 to 80 min.

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Atomic absorption spectrophotometric methods have been established for the determination of manganese in cements and their raw materials. The determination is interfered with mineral acids, but the constituents usually found in the samples did not give any disturbance. The calibration curve for manganese was found to be slightly deviated from a linear line. Manganese in the samples were determined rapidly with satisfactory accuracy and reproducibility.

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Iron, barium and bismuth in barium-ferrites were determined by the following procedure. Iron was determined by potassium-dichromate method. Barium was titrated with EDTA using EBT as an indicator after iron was masked with potassium cyanide. Bismuth was titrated with EDTA using XO as an indicator after iron was masked with either ascorbic acid or sodium pyrophosphate. By this method the determination of iron, barium and bismuth is made in 60 minutes and it's absolute error was within ±0.1%.

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