Conditions for the organic solvent extraction of the blue color (indothymol) formed by the reaction of thymol and ammonia nitrogen were investigated, and a following procedure was established.
Less than 30 ml of a solution containing 0.45 μg, of ammonia nitrogen was brought to pH about 10. After an addition of 2.5 ml of carbonate buffer (pH 10) solution containing 0.03% of sodium hypochlorite, within 2 min. 4 ml of thymol solution (prepared before use by mixing its 10% acetone solution with equal volume of 0.7 N sodium hydroxide solution) was added and pH was adjusted to 11.411.9. After about 2 hours, the solution was transferred to a polyethylene separatory funnel and diluted to about 50 ml with water. After an addition of 5 ml of sodium hydroxide solution (4N) and 18 g of sodium chloride, 10 ml of iso-butanol was added and extracted by shaking for 1 min. The organic. layer was separated and the absorbance at 675 mμ was measured.

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Chromazurol S (CAS) reacts with beryllium and gallium to form water-soluble blue complexes in the presence of cetyltrimethylammonium chloride. The absorption maximum of the Be complex is at 612 mμ, and its absorbance is nearly constant at pH 5.35.6. The Ga complex has the same absorption maximum with constant absorbance at pH 4.44.8. As the result of the continuous variation method, the composition of the complexes are estimated to be 1 : 2 (Be:CAS) and 1:4 (Ga:CAS) in excess of reagents. Neither of these complexes obeys Beer's law, but the calibration lines at 619 mμ for Be and at 618 mμ for Ga are linear over the range of 6×10^-76×10^-6 M metals. The sensitivities are very high, the molar absorptivity being 9.1×10⁴ for Be and 1.15×10⁵ for Ga. Al, Th, U, Fe, Cu, V, Ti, Au, Zr and Sn interfere remarkably.

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A new application of atomic absorption spectrometry was devised. The titration curves obtained by atomic absorption indirectly gave the micro amounts of chloride in the sample solution. The known amounts of silver nitrate was added to several aliquots of sample solution. The formed silver chloride precipitate was press-filtered through an apparatus using Sartorius membrane filter (MF 10, 0.01 μ) with polypropylene syringe. The excess silver of the filtrate was measured by atomic absorption spectrophotometry. A few micrograms of chlorine in 50 ml solution was accurately determined from the titration curve.
The author called this method the “atomic absorption spectrophotometric titration”.

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The relation between the spectral Intensities and the amounts of erosion of copper, manganese, silicon and titanium by spark discharge of different alloy systems as aluminum alloy and iron alloy. By spark discharge, the compositions of gaseous and solid phases were equal and the amount of erosion loss of every element was calculated as the product of the concentration of each element in the solid phase and the total amount of erosion of the electrode. A linear relation existed between the amount of erosion loss and the line intensity of every element. The variation of spectral line intensities called as the matrix effect was partly explained by an introduction of the values of electrode erosion.

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In the gas chromatographic approaches for quantitative determination of the components under consideration, there have been various methods for evaluating peak areas of the chromatogram, namely, planimeter tracing, triangulation, half-band width method, peak height×retention time method, gravimetry by cutting out the peak areas, and automatically operated electronic integrator. The authors introduced a new parameter involving a multiple of the peak height by the time required for the deflection of the recorder pen from base line to the peak point. The parameter exhibited a superior linearity with the actual peak areas to all other parameters mentioned above except the electronic integrator and the linearity reproduced in widely different patterns of the chromatograms.
It has been also found that most of the peak patterns of the chromatogram were well traced by the distribution function proposed by Levenspiel's mixing-diffusion model while the Gaussian and Poisson distribution functions could be applied only for chromatograms with sharp peaks. A geometric interpretation has been carried out with the linear relationship between the new parameter and the peak areas.

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A water-soluble formazan compound was synthesized. The acid dissociation constant of this compound was pK_a2=4.48 and pK_a3=11.83. The color reactions of this reagent with some metal ions were investigated and the stability constants of the complexes were obtained. The compositions of the complexes in the excess of metals were 1:1 for Cu, Zn, Ni and Co, and those in the excess of the reagent were 1:2 for Zn, Ni and Co, and 1:1 for Cu. Cu also formed a 1:2 complex at pH>8. The stability constants were determined by spectrophotometric and potentiometric methods. The values obtained by the former method were log K^A_CuA=15.50, logK^A_ZnA=8.4, logK^A_NiA=11.75 and logK^A_CoA=14.67. The reagent was applied as a metal indicator for the photometric titration of Cu with EDTA.

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1, 2, 3-Trimethyl-3-pyrazolin-5-thione reacts with Se(IV) in hydrochloric acid-sodium citrate buffer at pH 34.5 and precipitates quantitatively metallic selenium from a hot solution. The reaction was applied to the gravimetric determination of 20550mg of selenium with good result. The method was scarcely influenced by other ions. Te(IV) reacts with the reagent to form a water-soluble complex and hence the method is especially suitable for the separatory determination of selenium and tellurium.

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A quantitative analysis by detective currezt has been applied for alkaline earth metal ions during their development in ascending paper chromatography.
The applied D. C. tention is 3.0 V constant, and 5100μg of metallic salts is spotted on the filter paper.
(1) Optimum composition of the developer, (2) relation between the amount of ions and maximum current or the product of current-time, (3) the effect of precipitating agent and (4) influence of chelating agent are shown.
Complete separation of alkaline earth metals from alkali metals is achieved by the use of 80% ethanol as developer with the least spreading of R_f values.
The addition of potassium sulfate, potassium chromate and EDTA-2 Na gives good result in the mutual separation of alkaline earth metals.
The measured deviation in electrometric values for 1550μg of each alkaline earth metal ion is less than 2.0±0.5%.

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A method for the simultaneous determination of inorganic and organic mercury (MMC, EMC, and PMA) in water is described.
The atomic mercury generated by the reduction of mercury compounds circulates through the quartz absorption tube (Fig. 2), where absorption of 253.7 nm mercury resonance line occurs.
In 2 N sulfuric acid solution containing chloride ion, only inorganic mercury compounds are reduced by tin(II), while in 1 N sodium hydroxide solution containing trace of cupric ion, both inorganic and organic mercury compounds are reduced by tin(II).The concentration of organic mercury is calculated from the difference of absorbances.
The range of determination is 0.020.7 μg/100 ml and relative standard deviation is 2% at 5 ppb level. Sulfide ion, thiosulfate ion and silver(I) ion(in alkaline solution) interfere.
This method has been applied to the analysis of river waters and mine wastes.

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Lithium, sodium, potassium, strontium and barium were determined by the double-cell coulometry.
The authors used a new double-cell in which an electrolyte was separated into upper and lower cells by mercury layer laid on cation-exchange membrane. The sample was deposited to form the amalgam at the upper face of mercury and dissoluted into the lower cell.
The coulometric measurement was performed by an integration of the dissolution current of the amalgam under the controlled potential.
The current efficiency of potassium was about 97%, and it's standard deviation was less than one %. The time for a determination was 20 minutes.

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An atomic absorption spectrophotometric method for the determination of microamounts of silver in copper, aluminum and their alloys has been presented. This method involves the extraction of silver diethyldithiocarbamate with benzene and the measurement of absorbance of the extract. The interferences from matrix elements such as copper, aluminum and uranium, and from nickel and iron can be eliminated by addition of citric acid or EDTA. As little as 1 ppm of silver in copper, aluminum and their alloys can be determined by this method.
In order to obtain the optimum procedure, various factores such as instrument settings, condition for extracting silver diethyldithiocarbamate, effect of divserse ions, masking of interfering ions, etc. have been studied. The recommended procedures are as follows.
(1) Determination of silver in copper and copperbase alloys: 1.0 g of sample is decomposed with 20 ml of HNO₃ (1+1). 30 ml of EDTA solution (30w/v%) is added. After pH is adjusted to 8.5±0.1 by adding dropwise aqueous ammonia 1.0 ml of sodium diethyldithiocarbamate (DDC) solution (0.1 w/v%) is added. It is transferred into a 100 ml separatory funnel and shaken vigorously with 10 ml of benzene for 5 minutes. The benzene layer is subjected to the atomic absorption spectrophotometry. The absorbance at 3281 Å is measured and amount of silver is determined by referring to the calibration curve.
(2) Determination of silver in aluminum and aluminum-base alloys: 1.0 g of sample is decomposed with 25 ml of HCl (1 + 1) and several ml of H₂O₂ (30%) {High purity aluminum is decomposed with 10 ml of NaOH solution(10 w/v%) and made acidic with HCl}. 10ml of citric acid solution (50 w/v%) and 1.0 ml of EDTA solution (30 w/v%) are added.After pH is adjusted to 8.5±0.1 by adding dropwise aqueous ammonia, 1.0 ml of DDC solution (2.0 w/v%) is added. Silver is then determined in accordance with above mentioned procedure(1).

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Removal of sodium by cation-exchange followed by concentration of boron by anion-exchange is applied. to the photometric determination of as little as 0.01 ppm of boron in sodium metal or sodium hydroxide. About 5 g of sodium metal or 10 g of sodium hydroxide is dissolved in water, and the resulting solution (5 M NaOH, ca. 50 ml) is introduced onto a large column of strongly acidic cation-exchange resin (Amberlite CG-120, H-form, 100200 mesh, 35 mmφ × 180 mm) and a small column of strongly basic anionexchange resin (Amberlite CG-400, OH-form, 100200 mesh, 18 mmφ × 25 mm), in series, at a flow-rate of 58ml per min. The columns are washed with ca. 220 ml of water, and the boron adsorbed on the small column is then eluted with 10 ml of 1 M sodium hydroxide at a flow-rate of 1 ml per min. The first 2 ml fraction of the effluent is discarded, and the following 8-ml fraction is collected for the subsequent photometric determination with dianthrimide or with curcumin. An analysis requires 45hrs.
The determination of ca. 0.01 ppb of boron in water is also described.

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In order to determine the separability of ^113mIn from ¹¹³Sn-^113mIn, the adsorption behavior of these radionuclides for zirconium oxide were compared with those for hydrous zirconium oxide (HZO) under a variety of experimental conditions. From the batch distribution coefficients, the separability for these adsorbents was shown to be nearly equal over the concentration range of hydrochloric acid as an external solution from 6.1 × 10^-2 to 2.6 × 10^-1 M. It was shown from the column study that 7085% of ^113mIn free from ¹¹³Sn was recovered either from HZO column by passing through the hydrochloric acid solutions over the concentration range from 6.1 × 10^-2 to 2.6× 10^-1 M or from zirconium oxide column from 3.7 × 10^-2 to 4.2 × 10^-1 M. The merit of zirconium oxide over HZO is that the former is inexpensive, affords wide concentration range of the eluate and keeps zirconium well from breaking through the column. X-Ray diffraction patterns of zirconium oxide were considerably different from those of HZO.

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A small amount of tin which was contained in the surface of float process glass was determined by an X-ray fluorescence spectroscopy and by an electron probe microanalyser.
The standard samples were prepared by mixing various amounts of stannous oxide with soda-lime-silica glass batch and melting at 1350°C.
The content of tin was determined by phenylefluorone spectrophotometric method.
The result of electron probe microanalyser measurements suggested that tin was contained in a layer of 10 μ depth from the surface of the float process glass and surface content of tin was 1.46%. The X-ray fluorescence analysis showed that the tin content in total mass was 0.010%. Since the distribution of tin in standard glasses was homogeneous the mathematical correction for the difference of distribution of tin gave good agreement of the results by the two methods.

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A new inorganic packing material for permeation chromatographic column was developed. It consisted of agglomerates of microcrystals of highly pure θ-alumina of uniform crystal size, and was found to have characteristically sharp pore-size distribution. This column of porous θ-alumina could be used in water and the other organic solvents even at high temperature, showing resolving power as high as, or a little higher than, the conventional polystyrene gel. It was applied to the determination of molecular weight distribution of polyolefines, rubbers, cellulose, polyethylene glycol, polyvinyl alcohol, starch, protein, etc. Several physical properties of the alumina were also shown.

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D. c. arc excitation method in a controlled atmosphere was applied successfully to the spectrographic determination of small amounts of 14 rare earths and 12 non-rare earth metallic elements in yttrium oxide.
In order to establish the optimum conditions, studies were made on the effects of argon to oxygen mixing ratio in the atmosphere, the selection of analytical line pairs and the effect of ignition temperature of yttrium oxalate.
Base material(6-nines) was purified by cation-exchange technique by use of EDTA as eluent, then by homogenious precipitation method with diethyl oxalate.
The intensities of the CN band spectra and the background could be remarkably reduced by the use of argon-oxygen(4 : 1) mixed gas atmosphere and it was possible to obtain the analytical sensitivities several times stronger than in the excitation in air.
Spectrographic conditions were as follows: Shimadzu Ebert type spectrograph (GE-340); amounts of sample about 30 mg (Y₂O₃ 15mg + graphite powder 15 mg);excitation voltage 250V; arc current 10 amp.; slit width 20 μ; and duration of exposure 3 min.
The lower limits for the determination of the impurities were: 0.010.1 ppm for Yb, Mg, Al, Si, Ca, Mn, Fe, Ni and Cu; 0.11 ppm for Eu, Er, Tm, V, Cr, Sn and Pb; 1?10 ppm for La, Pr, Nd, Gd, Tb, Dy, Ho and Lu; and 20 ppm for Ce (as oxides, respectively).Coefficients of variation were 4.58.0% for rare earth impurities 5.515.9% for non-rare earth metallic impurities.

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A simple and accurate spectrophotometric method for the determination of micro amount of tin (0.010 ppm) in some drinks and seasonings with gallin has been established.
Organic substance in the sample was decomposed with a sulfuric acid-nitric acid mixture and tin in the solution was concentrated by an extraction with benzene as its iodide, by which was removed the interference from large amount of sulfate ion in the decomposed solution.
The reproducibility of the method represented as a coefficient of variation was 1.3% for vinegar. The time required for a single determination was about 2 hours.

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The thiocyanate complex of palladium reacts with zephiramine to give brownish yellow precipitate which is extractable into chloroform. The extract has an absorption maximum at 312 mμ. The molar absorbancy is about 3.7×10⁴ and invariable for at least 5 days. The composition of the extracted species was assumed to be 1 : 4 (Pd : zephiramine) by the continuous variation study. The Beer's law held over the range of 2×10^-62×10^-6M of Pd. Micro amounts of Pd were determined by this method. The effects of numbers of cations and anions were shown.

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Barium and strontium in barium carbonate of industrial grade have been determined by X-ray fluorescence whereby sample was fused with the flux containing sodium borate as a major component.
The coefficients of variation for barium and strontium were reduced to 0.06 and 0.61%, respectively, by the use of titanium dioxide as the internal standard and the improvement of the borax fusion method.Results of this method agreed closely with those of cation exchange separation method.

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The solution of thenoyltrifluoroacetone(TTA) in various pyridine bases can be used for the gravimetric determination of cobalt, zinc and cadmium. The precipitate formed by dilution (orange red for Co, white for Zn and Cd) is filtered, washed with 1% solution of the respective pyridine base and dried to constant weight at 41±1°C. The method is most satisfactory in preparing the precipitate at pH59 for cobalt and 68 for zinc and cadmium by using either β-picoline or γ-picoline together with TTA. In this case, the composition of the dried precipitate is represented by M(II) (C₈H₄O₂SF₃)₂ (C₆H₇N)₂ ; the gravimetric factors are 0.08571 for M(II) =Co, 0.09419 for M(II)=Zn and 0.1517 for M(II)=Cd.
The result is quantitative for cobalt and almost quantitative for zinc and cadmium. Most of cations except alkali metals interfere. The presence of ethylenediaminetetraacetate is particularly objectionable. From 2 to 10 mg each of the metal ion is determined by the method with 100 mg of TTA and 5ml of β-picoline or γ-picoline (preferably the latter).

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A method for handling volatile solid samples in organic microanalysis is described in which the sample is sealed and weighed in a metal capsule. That is, the sample for carbon and hydrogen by the conventional micro-Pregl method is sealed in an aluminum foil capsule, that for nitrogen by the micro-Dumas method is sealed in it with 5060 mg of cobalt oxide and that for nitrogen by the sealed tube combustion in decimilligram determination is sealed in a copper foil capsule of approx. 0.02 mm thickness.
The method is simple and accurate and requires no special attachments.

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