Inorganic ions being separated by paper chromatography are estimated continuously by means of an electric method.
Filter paper is clamped in due position with opposing two electrodes applied with D. C. voltage. When the developed inorganic ions come across the line of electrodes, an abrupt change in electric current is observed. A calibration curve is obtained from the height or area of the peak in the currenttime diagram.
The value corresponding to R_f in paper chromatography (represented as Rφ for convenience) is given by the ratio of the distance from electrodes to original point and that from original point to the solvent front when the current reaches its maximum, and is constant for each ion.
By selecting an organic solvent diffusing rapidly such as methanol for the developer the separation of peak is clear and the sensitivity of electric current is high. For example, there appears an intensive change of current 10500 μA for 550 μg of Na⁺ or K⁺.
Micro estimation by chromatography of alkali metals such as Na⁺ and K⁺is possible by this simple and rapid method.

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A method has been developed for the rapid spectrophotometric determination of iron and copper in fatty oils over the range of 0.1 to 1.8 ppm and 0.02 to 0.05 ppm, respectively.
To a Kjeldahl flask containing 5 g of sample oil were added 7 to 10 ml of concentrated sulfuric acid and then 50 ml of 60% hydrogen peroxide drop by drop to destroy organic matter. The digestion was completed in 40 minutes. The decomposition products of the reagent were only water and oxygen. Iron and copper in the colorless sulfuric acid solution obtained were determined by spectrophotometry. That is, iron was converted to iron thiocyanate, extracted into methyl isobutyl ketone (MIBK), and was determined by measuring absorbance at 495 mμ against MIBK.
Copper was converted to copper dibenzyl-dithiocarbamate, extracted into carbon tetrachloride, and was determined by measuring absorbance at 438 mμ against the pure solvent. The time required for an analysis was about 60 minutes.

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Linear alkyl benzene used extensively in the detergent industry contains usually small amounts of alkyl tetralins and alkyl indans as by-products. Determination of these by gel chromatography on Sephadex LH-20 was investigated. The optimum analytical conditions were : developing solution iso- propanol, glass column 1.8cm in diameter and 260cm in length and sample size 50 μl. Peak resolution between linear alkyl benzene and impurities in commercial products was more than unity. The contents of by-products were determined by comparison of chromatographic peak areas measured by a planimeter.

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It was reported, in the previous paper, that the lowering of accuracy in X-ray fluorescence analysis was attributable to a rise of mylar foil surface caused. by expansion of bubbles in vacuum. In this experiment, the degree of this rise of mylar foil was measured by using a specially designed apparatus, and the effects of temperature, amount of bubbles and thickness of mylar foil upon the height of expanded foil surface were investigated.
The results also indicated that scattered RhL_αX-ray as internal standard gave better results than scattered CrK_α X-ray against the variation in X-ray intensity caused from remaining bubbles in heavy oil. Solidified mixture of asphalt containing 5.20% sulfur and sulfur-free paraffin was satisfactory reference giving stable X-ray intensity for a long period. Heavy oil itself must be renewed at every measurement.

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Gas chromatography and infrared spectroscopy were combined to a unit process for rapid analysis of mixture of unknown substances by using a flow liquid cell. Organic vapor (carbon tetrachloride) was fed into hydrogen carrier eluted from the GC separation column, and the mixture was cooled in a small Liebig condenser (inner diameter 2 mm, length 20 mm) to collect the sample components with organic vapor. The condensed liquid was then led continuously to a flow liquid cell of a small volume and its spectrum was measured by scanning repetitively by the spectrometer. The change of transmittance was recorded by a strip chart recorder. By the restriction of slow scanning speed of the infrared spectrometer, the scanning was confined to several small regions. Experiments were carried out on benzene, octane, decane, methyl isobutyl ketone, pyrrole, etc. This new simple technique permits the rapid spectral examination or GC effluent and its qualitative and quantitative analysis.

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A simple and rapid method has been established for the determination of 0.00050.15% of tellurium in iron and steel.
The sample was taken up with sulfuric acid in which metallic tellurium coagulated in aggregates and was removed from interfering elements.
In hydrochloric acid solution, however, tellurium more or less dissolved in the presence of iron (II) as this was oxidized to iron (III) by air.
The separated tellurium was dissolved in nitric acid and perchloric acid. The solution was evaporated to vigorous fumes of perchloric acid, cooled, and to it was added 10 ml of 6N of hydrochloric acid. After boiling for 2 to 3 minutes, 5 ml of stannous chloride solution (100 g of stannous chloride dissolved in 100 ml of hydrochloric acid with 2 g of tin metal) and 2.0 ml of gum arabic solution (5%) were added successively.
It was diluted exactly to 100 ml with water, and the turbidity of the solution is measured using a 370 mμ filter.
The time required for an analysis was about 35 minutes.

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In the case of determining silicon in iron and steel spectrophotometrically by molybdenum blue method, white cast iron is generally excluded from this application as it shows abnormally low analytical values.
The authors have established a quantitative procedure for the determination of silicon in white cast iron without annealing the sample. The procedure recommended was as follows. The dissolving acid was prepared by mixing sulfuric acid (1+11) and 15% hydrogen peroxide in volume ratio 3 : 1, to. which was added 1.5% ammonium fluoride. After the sample was dissolved, the excess of fluoride ions was masked with boric acid, and silicon was subsequently determined by the usual analytical procedure.
The values obtained by this method were in good agreement with those by gravimetric method. The variation coefficient was 1% for both white cast iron and annealed samples.

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In order to obtain fundamental informations on the application of electron capture gas chromatography to the acaricides, retention times and peak area sensitivities were investigated on the four operating conditions containing 2% PEGA, 5% DC-11, 2% QF-1 and 10% SE-30.
Retention times of CPAS, azoxybenzene and FABB was short, and those of tetradifon and bromopropylate was long. Peak area sensitivity of quinoxaline derivatives and organic chlorine compounds involving sulfur was higher than organic chlorine compounds without sulfur. By the ccmbination of four operating conditions, mixture of 20 acaricides could be mutually separated. The linear ranges of calibration curves of kelthane, for example, was 0.540ng.

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A digital voltmeter combined with a paper tap punch has been designed and constructed as a digita recorder for a Perkin-Elmer Model 421 infrared spectrophotometer. This digital data recorder consist of two main systems, that is, the system for converting the input voltage from the spectrophotometer into the output signal on paper tape, and the controlling system for synchronizing the sampling interval witi the wavenumber drive. The D. C. standard voltage is fed from the Hg cell on the terminals of the absorbance potentiometer of the spectrophotometer and D. C. signal voltage is picked up by digital voltmeter and transferred into binary code decimal at the punch buffer. Controlling pulse for synchronizing is generated from the rotating transducer fixed on the shaft of wavenumber counter and the sampling is done at 0.1 wavenumber interval.
To examine the performance of this digital data recorder, two substances have been dealt, that is, methylene chloride as a sample with simple band shape, and methyl chloride as a sample with complicated band shape. The absorbance curve of ν₈ band of methylene chloride and ν₆ band of methyl chloride have been measured under various conditions and punched out on the paper tape. The punched data are processed by an electronic computer FACOM 270-30 and the areas have been obtained by numerical integration, mathematically correcting the non-linearity of the optical wedge of the spectrophotometer.
As the result, it has been proved that the integrated intensities are little influenced by scanning speed and spectral slit width used. By Wilson-Wells plot between concentrations (or pressures) and intensities thus measured, excellent results could be obtained as follows ; 2800 liter · mol^-1 · cm^-2 for ν₈ band of methylene chloride in CS₂ solution, and 400 liter·mol^-1 · cm^-2 for ν₆ band of methyl chloride in gaseous state, which are in good accordance with the results obtained by previous authors.
Comparing with conventional methods using a planimeter or weighing cut-out chart, this digital method has advantages of the elimination of personal errors, of the precision of the obtained results and of the reduction of the time and labors. The most remarkable superiority of this method is in that the non-linearity of optical wedge can be easily corrected using the absorbance-output voltage curve and in that the numerical integration can be easily carried out using Simpson's method.

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A modified procedure for iodometric determination of copper has been presented in which copper (II)solution is titrated directly with a mixed titrant of S₂O₃^2- and KI. More than 20 mg of copper (II) in 30 ml of solution (pH 5) is titrated potentiometrically with a mixed titrant composed of 0.075M of Na₂S₂O₃ and 0.3M of KI. For small amounts of copper (II), the concentration of KI in the titrant must be increased since it depends upon not only the amount but also the concentration of copper (II) in the solution to be titrated. The authors have arrived at a conclusion that the concentration of KI in the titrated solution at the end point must be higher than 0.02M. The relation is represented by the following equation:
n = 0. 02( V-v)/M·v -1
where V is volume of solution to be titrated (ml), v is volume of titrant consumed (ml), M is mole concentration of S₂O₃^2- in titrant, and n is necessary mole ratio of KI and S₂O₃^2- in the titrant. The mixed titrant is stable at least for 3 months. The modified procedure is as precise as the classical technique of iodometry, and has advantages in simplicity, economy of reagent and time etc. It may be applied also for some other oxidants.

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The proposed method consists in heating of reducing sugar with a basic 0.1 M Cu(II)-EDTA solution, which is followed by titration of liberated EDTA without filtration. About 30 g of NaOH should be involved. in a liter of 0.1 M Cu(II)-EDTA (Fig. 2). If the heating is carried out in steam (Fig. 1), the reaction between Cu(II) and sugar is complete in 4 minutes, and longer heating does not affect the reagent blank (Fig. 4). Less than 30 mg of reducing sugar is determined with 10 mlof 0.1 M Cu(II)-EDTA solution. In the case of glucose, the equivalent mole ratio of Cu(II) and sugar is 4 : 1. EDTA is titrated potentiometrically in buffered borate medium of pH 9 with 0.1 M Ca²⁺ or Cu²⁺ standard solution, by employing the combination of either Ag electrode and Ag⁺ indicator or Hg electrode and Hg²⁺ indicator. The Ag method is affected by the presence of a large amount of Cu₂O (corresponding to more than 10 mg of sugar) (Fig. 5), but the Hg method is not (Fig. 6). The potential break at the end point is larger in the Ag method. The standard deviation for 10 determinations is about 0.5%, and the time required for an analysis is about 10 minutes. Several of other reducing sugars are also determined in a similar way (Fig. 7).

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Chemical flames are generally used for atomizing of sample in the atomic absorption method. In these chemical flames, however, some elements (for example, Si, Al, Be and Ti) form inert molecules and reduce the free atom concentration and the sensitivity of analysis. The reducing N₂O-acetylene flame is the most suitable for these elements. The authors used the plasma jet flame for atomic absorption analysis, and tried to prevent the elements to form refractory oxides in the flame in an inert atmosphere of high temperature. As the solvents of sample before atomizing were compared several organic compounds, by measuring the efficiency of formation of free atoms and chemical interferences.
Among the elements examined, Mg, Ca and Al, the latter two elements were extremely sensitive to the state of atmosphere.

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Reports published on determination of nitrite with, GR reagent (sulfanilic acid, α-naphthylamine and tartaric acid as solid) have been different in the optimum ranges of time, temperature and pH required for its. full coloration. This paper says that the full coloration is maintained during 2080 min. at 1530°C and pH l.93.0 (Figs. 1 and 2). The pH is about 2.3 when 0.1 g of GR reagent is added to a 20 ml sample solution.
Several sulfur compounds and iodide ion interfere with the coloration, but it is proposed that the interferences are simply eliminated by adding 50 mg of mercuric chloride to a 20 ml solution (Figs. 39). If the latter causes precipitate, the filtrate is used for the coloration. Mercuric chloride may be effective also when other similar reagents are used to yield the azo-dye for determination of nitrite (Fig. 10). Thus, it is possible to determine nitrite in hot spring, lake and waste waters containing sulfur compounds and iodide.

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A method of EDTA masking-coprecipitation of minute amount of antimony was presented, and was applied with good result to the determination of antimony in iron and steel. The method of determination was square wave polarography using 3 N hydrochloric acid as supporting electrolyte. The recommended procedure is as follows.
Dissolve 0.20.5 g of sample in the least amount of sulfuric acid. Add 70 mg of Cr(III) as a coprecipitant and EDTA equivalent to sample, and make alkaline with ammonia. Separate the precipitate by centrifuge with 3000 rpm for 5 min. in a 50 ml centrifuge tube. Wash the precipitate once with water, and dissolve it in 3 N HCl to make up to 25 ml. Take the polarogram (from -0.07 V to -0.25 V vs. Hg pool) without deaeration. The working curve was prepared by carrying through the procedure on the solution containing equal amount of iron with the sample solution added with standard antimony solution. As much as 150 μg of Bi, 100 μg of Cu, 1 mg of tin and lead, and 100 μg of tantalum were permitted.

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Natural radionuclides, such as actinium-227, radium-228 and their daughter nuclides, were subjected to the rapid chemical separation by paper electromigration. The substances containing about 1 μc radionuclides were migrated for 3 min. under a potential gradient of 2000 volt/29 cm on the paper dipped with the back ground electroltye of 0.1 M ammonium formate.
The detection of alpha radionuclides of this strip was carried out by using the alpha particle track detector with celluloid film. Alpha irradiated films are etched in 6 N NaOH at 50°C for 15 min. and compared with the autoradiographs on X-ray films, and thus the alpha nuclides could be easily distinguished from the beta and gamma nuclides. The decay and growth of alpha track after the separation were used fathe identification of alpha emitting nuclides on the strip. The authors could also confirm the half life of the nuclide from measurements of the number of alpha track obtained from the microscopic observation. From these results, the migration order of elements contained in samples was assigned as follows: Th, Po, Bi (starting point) <Pb, Ac<Ra<T1.
The method is useful for the chemical investigation of alpha nuclides, such as natural radionuclides and actinide elements.

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A Method for the atomic absorption spectrometric determination of 0.0010.03% of iron in titanium, copper and magnesium was investigated. The recommended conditions were: wavelength 248.3 mμ, current of hollow cathode lamp 30 mA, slit width 0.25 mm, air pressure 1.8 kg/cm² and acetylene pressure 0.17 kg/cm². Iron in titanium, copper and magnesium could be determind by atomic absorption measurement after extraction with MIBK. Much higher sensivity was obtained for iron in titanium by using oxine-MIBK extraction. The matrix elements and other constituents usually contained in titanium, copper and magnesium did not interfere. The method was very rapid and the results of recovery test on practical samples were satisfactory.

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Amperometric titrations of cadmium, zinc and manganese(II) with EDTA using oxalate as a masking agent were investigated.
Fifty milliliters of 0.2M oxalate solution adjusted to pH 6.0 for cadmium and zinc or 8.0 for manganese(II) was amperometrically titrated with 0.01M EDTA solution at a potential of -0.80, -1.60 and -1.75 V vs. S. C. E., respectively, for Cd, Zn and Mn.
The lower limits of determination were 6 ppm for cadmium and 3 ppm for zinc and manganese(II). Permitted amounts of 18 metal ions with errors of 2% were tabulated and they were compared with values calculated from the conditional equilibrium constants.

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Each metal ions in mixtures of chromium, manganese or iron and other heavy metals were examined as to be titrated together or separately by potentiometric method in many kinds of buffer solutions by using the recording titration apparatus (RAT-IS) which describes the titration curve automatically for the indication of the end point. The suitable kinds of buffers were disclosed for EDTA titration of Cr³⁺, Mn²⁺ or Fe³⁺ in mixtures with other heavy metal ions.

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Each metal ions in mixtures of nickel, cobalt, or aluminum and other heavy metals were examined as to titrated together or separately by potentiometric method in many kinds of buffer solution by using the recording titration apparatus(RAT-IS) which describes the titration curve automatically for the indication of the end point. The suitable kinds of buffers were shown in Tables for EDTA titration of Ni²⁺, Co²⁺ or Al³⁺ in mixtures with other heavy metal ions.

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Each metal ions in mixtures of alkaline earth metals or of those with other heavy metals were examined as to be titrated together or separately by potentiometric method in many kinds of buffer solutions by using the recording titration apparatus (RAT-IS) which describes the titration curve automatically for the indication of the end point. The suitable kinds of buffers were shown in Tables for EDTA titration of alkaline earth metals in their mixtures.

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To an acid solution containing beryllium was added 1 ml of 5% EDTA solution for less than 3 mg of Al or 5 ml for 314 mg of Al, and pH was adjusted to 3.54.5 with 0.25 M sodium acetate solution. Its pH was then adjusted to 5.1 with 0.25 M sodium acetate solution, and 0.6 ml of 0.25% Chromazurol S solution and 2 ml of 0.5% Zephiramine solution were added. It was diluted to 25 ml with water and allowed to stand for 30 min. The absorbance was measured at 610 mμ against a reagent blank. From 0.05 to 2μg of beryllium was determined by this method in the presence of up to 14 mg of aluminum. In the presence of more than 3 mg of aluminum, the calibration curves were prepared for solutions containing the same amount of aluminum.

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Salicylamide in mixed pharmaceutical preparations was determined by infrared spectroscopy by using 3425 cm^-1 absorption of acidamide as the key band. A sample corresponding to 75 mg of salicylamide was taken in a glass-stoppered conical flask and extracted by chloroform (for IR use) to make up to 50 ml. The measurement was carried out by using 1.0mm KRS-5 cell with 3300 cm^-1 or 3470 cm^-1 as the base line. As shown in Table II, the results agreed well with those by colorimetric determination. The influences of about 40 sorts of drugs and constituent commonly present in antihistamine for common cold were also examined (cf. Table I).

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Lead and cadmium in 0.1Mpotassium chloride -0.01M hydrochloric acid (20ml) are electrodeposited on a mercury-plated platinum electrode (0.7 mm diam.×2.2 mm) at -1.0Vvs. S.C.E. for 30 min. After 30 to 60 sec, an anodic dissolution curve is recorded by a radio-frequency polarograph (455 kc/s, 100% amplitude modulation with 200 c/s square wave, 4 V) at the scan rate of 0.2 V/min. The peak height-concentration curves are linear over the range of 0.01 to 0.1μg of lead and 0.1 to 1μg of cadmium. The method is applied to the determination of lead and cadmium in vanadium in combination with the anion-exchange separation.

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Chlorine in tantalum metal was titrated argentometrically by the end point detections presented above. The method using test paper was reported previously {this journal, 14, 193 (1965)}. In the latter (derivative polarographic) method, the authors worked out the method by which the effect of the solubility of silver chloride could be overcome. Two drops of an ammonia, solution of the chloride was added to the sample solution, and the titration was carried out in ethanolic media (50% v/v) containing nitric acid. Well defined titration curves could be obtained by this method. Several tens micrograms of chloride ions in 100 ml of the sample solution could be titrated with satisfactory results.

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Vaporization of mercury from organomercury cornpounds has been followed by atomic absorption method by the use of long absorption tube shown in Fig. 1. When the solution containing phenyl mercuric acetate was exposed to U.V. radiation, absorbance at 2537 Å of mercury resonance line increased with time, but no increase was observed on the neighbouring line. One of the causes of the loss of organomercury compounds may be explained as the vaporization of mono-atomic mercury produced by U.V. radiationfrom organomercury compounds.

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