Dual-wavelength spectrophotometry made it possible to determine the isomeric guaiacolsulfonates separately in pharmaceutical preparations. The recommended procedure is as follows :
I. Determination of potassium guaiacol-4-sulfonate and guaiacol-5-sulfonate : A sample containing about 1.0 mg of guaiacolsulfonates is dissolved in water and diluted to 50 ml with 0.1 N sodium hydroxide. The content of 4-sulfonate is obtained from the absorbances at 242 nm and 258 nm with the standard solution. The content of 5-sulfonate is also obtained from the absorbances at 237.5 nm and 300.9 nm with proper standard solution.
II. Determination of potassium guaiacol-4-sulfonate and 5-sulfonate in pharmaceutical preparations : A sample containing about 100 mg of guaiacolsulfonates is dissolved into 100 ml of water and filtered with glass-filter (No.3). The initial 20 ml filtrate is discarded, and the subsequent 20 ml filtrate is passed through the freshly conditioned strongly-basic ion-exchange resin column. After washing with 0.1 N HCl-ethanol (flow rate 1 ml/min), elution is carried out with the same eluant with flow rate 4 ml/min. The eluate is collected and diluted to 200 ml in measuring flask. The determination of 4- and 5- sulfonates can be carried out by dual-wavelength spectrophotometry following the Determination I.

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A method was presented for the determination of microgram amounts of selenium and applied successfully to the determination of selenium in steels. The method consists of the evolution of hydrogen selenide, its fixing on a silver nitrate test paper, and the measurement by X-ray fluorescence spectrometry.
Procedure : Transfer a sample solution containing up to 100 μg of selenium into a evolution bottle (200 ml Erlenmeyer flask). Add 25 ml of 12M hydrochloric acid, and dilute the mixture to 50 ml with water. If selenium (VI) is present, heat the solution to just boiling for reduction to selenium (IV). After addition of 2 ml of stannous chloride solution (40w/v%) and 10 g of granular zinc, connect immediately with a capture bottle to which a test paper has been attached. After standing the apparatus for 15 minutes, remove the test paper, set it on a sample holder of the equipment, and count the X-ray fluorescence intensity in a vacuum by SeK_α line (2θ= 31.88) using a chromium target X-ray tube (50 kV 20 mA) and LiF monochrometer.
The intensity of X-ray fluorescence is almost proportional to the selenium amount (up to 100 μg). The standard deviation was 3.4% (with 10 μg of selenium) in five runs.

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The determination of trace amounts of dispersed oils (mineral oil, fatty oil and fatty acid) in waste water been studied. The oils in water can be extracted with a small amount (1/100, V/V) of carbon tetrachloride, if 20 g of sodium chloride is added to 700 ml of water. The infrared absorption of the extract is measured at 1900 to 1400 cm^-1, and the concentration of mineral oil, fatty oil and fatty acid can be calculated from absorbance at 1750, 1710 and 1460 cm^-1. The detection limit is 0.3 to 1 ppm when 700 ml of water is used. The time required is about 30 minutes.
Proposed method is effective for routine work and seeking the pollution source.

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The analysis of phenols were attempted by the use of atomic absorption spectrophotometry (AAS) for research of indirect determination of organic compound by AAS.
The phenols were determined by AAS and satisfactory results were obtained. The following compounds were investigated: phenol, ο-cresol, m-cresol, p-cresol, p-ethylphenol, ο-isopropylphenol, ο-sec-butylphenol, 3, 4-xylenol, 3, 5-xylenol, ο-aminophenol, ο-chlorophenol, p-chlorophenol, p-hydroxyphenylacetic acid, ο-hydroxybenzoic acid, m-hydroxybenzoic acid, p-hydroxybenzoic acid, propyl-p-hydroxybenzoate, p-nitrophenol, α-naphthol, β-naphthol and α-nitroso-β- naphthol. To prepare the sample solutions, the phenol was dissolved in water, and the other phenols in methyl alcohol.
The recomended procedures are as follows: Methyl alcohol was eliminated by evaporater when it was used as the solvent, and 3 ml of water was added (but in phenol, 1 ml of the phenol solution was added to 2 ml of water). To this solution were added 1 ml of 1.73 N acetic acid and 1 ml of 40.64 mg/ml sodium cobalt nitrite, and the solution was heated on a water bath for 5 minutes at 100°C. After the solution had been cooled, the cobalt-complex containing phenols was extracted with 10 ml of MIBK. The extracted solution was centrifuged and was subjected to AAS.
Since the measurement of cobalt was influenced by the concentrations of acetic acid and cobalt ion, the concentration of acetic acid was kept at 0.141.00 N, and the molar ratios cobalt ion/phenols were kept over 1.89 at measurements of both the sample and the calibration.
Those compounds did not interfere with the phenol determination which are K⁺, Ca²⁺, Mg²⁺, Pb²⁺ and Zn²⁺ even in about 8 times the phenol concentration, Ni²⁺ and Al³⁺ in about 16 times, ephedrine in about 10 times, benzoine in about 15 times, benzoic acid in about 20 times, and nitrobenzene in about 80 times, but Cu²⁺ and Fe³⁺ in about 0.08 times, and aniline in about 5 times interfered with the phenol determination. The interference of metal ion and aniline on the determination of phenol except phenol were successfully eliminated by the extraction of phenols from the acidic aqueous solution into chloroform.
The calibration curve were linear over the rangs 0.102.00 mg of phenol, 2.5014.28 mg of ο-cresol, 2.357.28 mg of m-cresol, 1.527.00 mg of p-cresol, 1.4541.50 mg of p-ethylphenol, 0.996.00 mg of ο-iso-propylphenol, 1.0012.50 mg of ο-sec-butylphenol, 1.243.00 mg of 3, 4-xylenol, 1.404.30 mg of 3, 5-xylenol, 0.7711.15 mg of ο-aminophenol, 2.139.00mg of ο-chlorophenol, 0.505.20 mg of p-chlorophenol, 0.805.08 mg of p-hydroxyphenylacetic acid, 20.51 mg of ο-hydroxybenzoic acid, 5.5223.00 mg of m-hydroxybenzoic acid, 2.5816.10 mg of p-hydroxybenzoic acid, 0.111.58 mg of propyl-p-hydroxybenzoate, 2.7212.40 mg of p-nitrophenol, 0.040.70 mg of α-naphthol, 0.051.53 mg of β-naphtol, and 0.160.38 mg of α-nitroso-β-naphthol in 10 ml of MIBK each. Per cent recovery of phenols ranged from 94.5 to 104.5%.
It has been found that this method is very easy and simple in the procedure and is satisfactory applicable to the quantitative determination of phenols.

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Primary amines were determined satisfactorily by atomic absorption spectrophotometry (AAS) by the use of copper-complex formation. The recommended procedures are as follows: The complex-formation reagent solution is prepared by mixing 3.372 g of triethanolamine, 0.205 g of 5-nitrosalicylaldehyde, 1 ml of 50% acetaldehyde solution, 5 ml of 4% cupric sulfate and water (final volume 50 ml). Each sample solution of 27 amines is added 1 ml of the complex formation reagent solution and diluted to 10 ml with water. After standing 1 hour, the precipitate of copper-amine complex is filtered off. Then, (i), (filtrate method) 1 ml of the filtrate is diluted to 10 or 25 ml with water, and the copper content is measured by AAS; (ii), (precipitate method). The precipitate (copper-complex) is dissolved into 10 ml of 12.6 N nitric acid and diluted to a proper volume (100, 250, or 500 ml), then analyzed with AAS.
The limit of determination for 23 primary amines are as follows: methylamine (0.04 mg by filtrate method, 0.19 mg by precipitate method), isopropylamine (0.14, 0.41), n-hexylamine (3.92, 3.92), cyclohexylamine (0.59, 1.17), hexamethylenediamine (0.32, 1.28), triethylenetetramine (0.73, 1.46), aniline (0.03, 0.55), ο-toluidine (-, 0.75), m-toluidine (0.50, 1.00), p-toluidine (1.20, 1.20), ο-aminophenol (0.71, 1.41), m-aminophenol (0.66, 1.31), p-aminophenol (0.74, 1.48), ο-anisidine (5.97, 3.98), m-anisidine (1.65, 3.29), m-phenylenedi- amine (0.49, 0.53), p-phenylenediamine (0.34, 0.68), benzidine (0.20, 0.20), 3, 3'-dimethylbenzidine (0.47, 0.47), p-chloroaniline (0.69, 0.69), procaine (0.50, 7.05), α-naphtylamine (0.52, 0.52), β-naphthylamine (0.53, 1.06). But ο-nitroaniline, m-nitroaniline, p-nitroaniline and 4-nitro-1-naphthylamine couldn't analyze by both method, and ο-toluidine couldn't analyze by filtrate method. The coexistence of 2030 times of secondary or tertiary amines does not interfere. Several metal ions such zinc, magnesium, and calcium cause severe interferences and must be removed beforehand.

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An ethanol-formic acid-nitric acid mixture containing 0.0050 m mol of sevral rare earth pairs from Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, or Y was passed through a column packed with strong-base anion exchange resin, Amberlyst-A29 in the nitrate form (φ 1.2 cm×21 cm bed), and the rare earth band formed on the column was eluted with the various mixtures of ethanol, formic acid, and nitric acid. In general the heavier rare earth passed through the column at the faster rate than the lighter one, and Y is eluted between Er and Tm. The most effective compositions of the mixtures for separations of adjoining rare earth groups are,
(1) for Yb and Lu, C₂H₅OH-26 M HCOOH-13 M HNO₃ (volume ratio, 93 : 3 : 4)
(2) for Tm and Yb, C₂H₅OH-26 M HCOOH-13 M HNO₃ (90 : 5 : 5)
(3) for Er, Y, and Tm, C₂H₅OH-20 M HCOOH-13 M HNO₃ (90 : 5 : 5)
(4) for Ho and Er, C₂H₅OH-15 M HCOOH-7 M HNO₃ (90 : 5 : 5)
(5) for Tb, Dy, and Ho, C₂H₅OH-23 M HCOOH-13 M HNO₃ (85 : 7 : 8)
(6) for Gd and Tb, C₂H₅OH-20 M HCOOH-13 M HNO₃ (80 : 10 : 10)

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An ethanol-formic acid-nitric acid mixture containing 0.0050 m mol of La, Ce, Pr, Nd, Sm, Eu, or Gd was passed down a column packed with a strong-base anion exchange resin, Amberlyst A29 in the nitrate form(φ 1.1 cm×21 cm bed), and the rare earths adsorbed on the column were eluted with various mixtures of ethanol, formic acid, and nitric acid.
In general the heavier rare earth passed down the column at a faster rate than the lighter one. The most effective compositions of the mixtures for separations of adjoining rare earths were,
(1) for Eu and Gd, C₂H₅OH-15 M HCOOH-10 M HNO₃ (80 : 10 : 10 volume ratio)
(2) for Sm and Eu, C₂H₅OH-10 M HCOOH-7 M HNO₃ (80 : 10 : 10)
(3) for Sm, Eu and Gd, C₂H₅OH-15 M HCOOH-7 M HNO₃ (80 : 10 : 10)
(4) for Nd and Sm, C₂H₅OH-10 M HCOOH-7 M HNO₃ (75 : 15 : 10)
(5) for Pr, Nd and Sm, C₂H₅OH-5 M HCOOH-7 M HNO₃ (75 : 20 : 5)
(6) for Ce(III) and Pr, C₂H₅OH-5 M HCOOH-7 M HNO₃ (70 : 25 : 5)
(7) for La and Ce(IV), C₂H₅OH-5 M HCOOH-7 M HNO₃ (70 : 25 : 5)

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Manganese(II) catalyses the hydrogen peroxide oxidation of anthraquinone dyes such as Acid Blue-45, Acid Blue-25, Acid Violet-43, etc. in aqueous carbonate solutions. This catalytic reaction was utilized to indicate the end point of titration in the determination of manganese(II) with EDTA. The optimum of the catalytic action of manganese(II) ion was found to be limited to relatively high carbonate concentration (0.30.4 M) and narrow pH ranges (between 8.4 and 9.7). Copper(II) catalyses also the reaction in ammonium carbonate solution. In both cases, the rate of dye oxidation is the zero-th order with respect to a dye concentration.
Among the anthraquinone dyes investigated, Acid Blue-45 (sodium salt of 1, 5-dihydroxy-4, 8-diamino-anthraquinone-2, 6-disulfonic acid)was best suited for analytical purposes. The recommended procedure for manganese determination is as follows : to about 50 ml portion of 0.4 M carbonate solution containing known amounts of EDTA, add 1 ml of 0.05% Acid blue-45 and 1 ml of 3% hydrogen peroxide. Titrate the solution with a manganese(II) solution. At the end point, the catalytic oxidation of the dye proceeds instantaneously and the solution turns from blue to colorless.
This catalytic titration method was applied to determine zinc, cadmium, mercury and lead by back-titration of excess of EDTA with standard manganese(II) solution. The results were in good agreement with those obtained by the titrimetric method with BT or XO as an metal indicator. The Acid Blue-45 indicator system is superior to the Alizarin Red S method, because in the former case no appreciable fading of dye was observed near the end point of titration. The relative standard deviation for the catalytic titration of manganese was 0.13%.

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A method was proposed for the determination of 0.04 to 10 ppm arsenic and antimony in silicates by the atomic absorption spectrometry with a argon-hydrogen flame and arsine and stibin generation method. The difficulties involved in the determinations are interferences of plutinum ion and nitric acid for arsenic and of copper, cobalt, nickel, iron ions and nitric acid for antimony. Thus, the following procedures are recommended :
Arsenic: Take 0.1 to 1.0 g of sample into a Teflon beaker and add 2 ml of HNO₃, 5 ml of H₂SO₄(1+1), 10 ml of HF and 2.5 ml of 2% KMnO₄. Heat until SO₃ fumes appear, then add 3 ml of H₂SO₄(1+1) and evaporate almost to dryness. Dissolve the residue by heating on a hot water bath with 20 ml of 1.8 N HCl. Transfer the solution into a reaction bottle and add 1 ml of ferric chloride(Fe 10 mg/ml), 1 ml of 40% KI and 2 ml of 20% SnCl₂, then allow it to stand for 10 min. Add 1g of zinc powder and immediately connect the reaction bottle to the collection vessel and allow to react for 90 sec by agitating the mixture with a magnetic stirrer. Introduce the generated arsine to the atomic absorption spectrometer and determine arsenic.
Antimony: Take 0.1 to 1.0 g of sample in a platinum dish and add 3 ml of HNO₃, 5 ml of H₂SO₄(1+1) and 15 ml of HF, then evaporate near to dryness. Dissolve the residue by heating with 4 ml of H₂SO₄(1+1) and 10 ml of 10% tartaric acid, then evaporate to 10 ml. After filtrating, add 5 ml of H₂SO₄(1+1) and dilute to 17 ml with water. Transfer the solution into a separatory funnel and add 2 ml of 20% ascorbic acid and 0.5 ml of 0.4 M KI, then extract for 3 min twice with 10 ml portions of benzene. Wash the combined organic phase twice with 20 ml portions of 5 M H₂SO₄-0.01 M KI solution. Shake the organic phase for 3 min with 10 ml of 0.2% EDTA solution. Withdraw the aqueous phase into a beaker and add 3 ml of H₂SO₄(1+1), 3.5 ml of 30% H₂O₂ and 0.5 ml of magnesium sulfate solution(Mg 10 mg/ml), then evaporate to dryness. Dissolve by heating with 25 ml of HCl(1+1) and transfer into a reaction bottle. Add 1 g of zinc powder and collect the generated gas for 120 sec, then introduce it to the atomic absorption spectrometer and determine antimony.
The relative standard deviations in the determination of 0.5 to 10 μg arsenic and antimony was 3 to 9%. The methods were satisfactory applied to the standard silicate samples.

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A rapid and simple method for the simultaneous determination of inorganic and organic mercury in water was studied. The apparatus used were a gas washing vessel (capacity 100 ml), mercury vapour detector tubes and a handy sampling pump (aspirator). Silica gel of 4060 mesh mounted with copper iodide are filled up in the mercury vapour detector tube which is 2 mm in diameter and 60mm in length. The mercury vapour is determined utilizing empirical relationships between the length of stain and its concentration.
Analysis was carried out as follows : Sample water (50 ml) containing mercury compounds was placed in a gas washing vessel and reduction reagents were added. The reduced mercury vapour purged by the aeration in this vessel was led into the detector tube by sucking with a pump or an aspirator.
The stained length in the tube was proportional to the amounts of mercury compounds in water. The mercury compounds differed one another in the reactivity. Both Hg(I) and Hg(II) were reduced by adding 5 ml of 18 N sulfuric acid and 5 ml of 5 N sodium chloride with tin (II) (acid method). But organic, mercury compounds were not reduced with the acid method. On the other hand, Hg(I), Hg(II), phenyl mercuric acetate, methyl mercuric chloride were reduced with tin(II) after addition of 10 ml of 10 M sodium hydroxide and traces of Cu(II) ion (alkali method). The ratio of the stained length to the amounts of mercury compounds in water by the acid method was equal to that by the alkali method.
The length of a stain had a difinite value in correspondence to the amounts of mercury in water when the volume of aeration for separating mercury from water attained to 600700 ml at the average velocity 75150 ml/min.
Interference of the reduction of mercury compounds with coexisting substances in alkali method was smaller than that in the acid method except when silver ions were present. When nitrous ions were present more than 10 ppm nitrogen dioxide was generated and disturbed the determination of mercury by the acid method, because nitrogen dioxide produce a stain similar to that produced by mercury (grayish yellow or pale orange). However, the stains of hydrogen sulfide (pale brown) and ammonia (light blue) which were generated from sulfide ions in the acid method and ammonium ions in the alkali method, respectively were distinguishable from that of mercury.
This method was applied to the analysis of submicrogram amounts of mercury in waste waters and river waters. In the majority of cases the results approximately agreed with those obtained by atomic absorption spectrophotometoric method with wet digestion.
The range of determination was 0.050.7 μg of Hg in 50 ml and the coefficient of variation was 5% at 14 ppb level. The time required for a sample was about 8 minutes.

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A selective method is reported for the spectrophotometric determination of small amounts of titanium. The method is based on the complex formation of titanium (IV) with diantipyryl-2-hydroxyphenylmethane (DHPM).
Titanium(IV) forms a stable and yellow complex with DHPM in an aqueous methanolic medium. The complex has an absorption maximum at approximately 347 nm, and can be extracted quantitatively into dichloroethane in the presence of anions such as perchlorate, thiocyanate and iodide. Fundamental conditions for the determination of titanium including effects of concentrations of acid, DHPM and methanol, effect of standing time, extractability of the complex, etc. were studied and a practical method for the determination was established.
The outline of the procedure is as follows; Transfer the sample solution containing less than 120 μg of titanium(IV) into a 25-ml volumetric flask and add 1 ml of sulfuric acid (1+19) or hydrochloric acid(1+6). If necessary, add 1 ml of 10% ascorbic acid solution. Then add 5 ml of 0.7% DHPM solution in methanol and dilute to the mark with water. After standing for 20 minutes, measure the absorbance of the solution at 347 nm against a reagent blank solution. If the absorbance of the colored solution is too low to measure, transfer all of the colored solution into a 50-ml separatory funnel, and add 4 ml of 1 M sodium perchlorate solution and 10.0 ml of dichloroethane. Extract titanium(IV) complex by shaking for 2 minutes, and measure the absorbance of the organic phase at 338 nm against a reagent black solution prepared in the similar manner.
Under the optimum conditions, a good linear relationship between the absorbance and the concentration of titanium was obtained up to at least 4.8 ppm titanium and the molar absorptivity at 347 nm was 9.1×10³ l/mol·cm.
Iron(III), vanadium(V), chromium(VI), large amounts of zirconium(IV), perchlorate, iodide, thiocyanate, tartrate and citrate interfered with the determination, but the other common ions did not interfere. Interferences by iron(III), vanadium(V) and chromium (VI) could be eliminated by reduction of these ions with ascorbic acid. Interferences by perchlorate, iodide and thiocyanate could be removed by extracting the colored solution with dichloroethane.
The method established was applied to the determination of titanium in kaolin and a satisfactory result was obtained.

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In a previous paper, the effect of substituents on the fluorescence intensity of the beryllium complex of 5-hydroxychromone had been reported. The present paper describes a similar investigation on the beryllium complexes of 5-hydroxyflavone (2-phenyl derivative of 5-hydroxychromone), 5-hydroxyisoflavone (2-phenyl derivative of 5-hydroxychromone) and their derivatives. Table I shows the reagents synthesized. All of them form complexes with beryllium, which show the most intense and constant fluorescence when they were extracted from a solution of pH 810 into carbon tetrachloride. The introduction of alkyl group (CH₃<C₂H₅) into the 2-position of 5-hydroxyisoflavone increases the fluorescence intensity. Furthermore, the introduction of methoxyl group to the 7-position, accompanied by the shift of maximum excitation wavelength to a shorter wavelengths, greatly increases the intensity excited at 366 nm. 2-Ethyl-5-hydroxy-7-methoxyisoflavone seems to be a suitable reagent for the fluorometric determination of beryllium. The recommended analytical procedure is as follows : Five milliliters of 1×10^-3M methanol solution of the reagent, and additional 7.5 ml of methanol in order to give final concentration of 50 vol% methanol, together with 5 ml buffer solution (boric acid and sodium hydroxide, 0.25M in borate, pH ca. 9) are added to a beryllium solution, and the mixture is diluted to 25ml with water. After about thirty minutes, the formed complex is extracted by shaking with 10 ml of carbon tetrachloride for about one minute. The organic phase is dried over sodium sulfate. Its fluorescence intensity is measured with an excitation wavelength of 366 nm, using a secondary filter transparent for wavelength>ca. 430 nm. Temperature change, within the range of 1025°C, have no effect on the intensity. The complex is stable for at least one hour. The calibration curve is linear in the range of about 0.010.3 μg of beryllium when an aqueous solution of 1 μg/ml fluorescein sodium salt is used as the reference standard. The effect of diverse ions was also examined.

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For the fluorometric and spectrophotometric determination of cadmium, methods with the extraction of a cadmium thiooxine complex into chloroform were studied.
It was found that cadmium thiooxine chelate can be extracted with ο-phenanthroline in a wide concentration range and used for spectrophotometric determination. Besides, ο-phenanthroline can be used as a masking reagent for iron, nickel and cobalt.
For the fluorometric determination of cadmium it was found that ο-phenanthroline decreased the intensity of fluorescence and its use should be avoided.
The effect of diverse 29 ions on the cadmium determination was studied; a small amount of copper, iron, nickel and cobalt can be masked with potassium cyanide, but bismuth, lead, zinc and gallium interfere with significantly. By extraction at pH 14, the effect of bismuth and lead can be reduced to a minimum. Gallium is not extracted at pH 14. Zinc must be removed before analysis.
The recommended procedure for the fluorometric determination is as follows:
Take 1040 ml of sample solution containing less than 15 μg of cadmium into a beaker. Add 0.2 mlof 0.2% thiooxine (6N HCl solution) to the sample solution. Adjust the pH to 4 or 14 (in case of bismuth or lead coexistence) and dilute to 50 ml. Transfer the solution into a separatory funnel and extract the cadmium chelate with 10ml of chloroform by shaking the funnel for 2 minutes. Then transfer the extract to a quartz cell. The fluorescence intensity at 515 nm is measured at the excitation wavelength 365 nm against a 0.2 μg/ml uranine solution as the reference. The calibration curve was found to be linear up to 7 μg of cadmium. The range of determination with accuracy is from 0.5 μg to 15 μg.
The recommended procedure for the spectrophotometric determination is as follows :
Take 1040 ml of sample solution containing less than 100 μg of cadmium. Add 3 ml of 0.1% ο-phenanthroline solution and 0.5 ml of 0.2% thiooxine solution. Then extract the cadmium complex in the same way as the procedure for the fluorometric determination. The absorbance at 403 nm is measured against the reference of the reagent blank.
The calibration curve obeys Beer's law up to 90 μg (in 10 ml CHCl₃) of cadmium.
The proposed methods were applied to the determination of cadmium in bismuth alloys composed of bismuth, lead, tin and cadmium. Good results were obtained by the fluorometric method. In case of spectrophotometric method bismuth and lead must be removed before analysis.

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The interference of perchloric acid on the thirteen elements in atomic absorption spectrophotometry in an air-acetylene flame, in an air-hydrogen flame and in a nitrous oxide-acetylene flame were studied.
A Nippon Jarrell-Ash Model AA-1 atomic absorption/flame emission spectrophotometer was used. Two slot type burners for air-acetylene flame (slit width : 0.5×100 mm) and nitrous oxide-acetylene flame (slit width : 0.4×50 mm), and a total consumption type burner (HETCO burner) for air-hydrogen flame were used.
Hollow cathode lamps of each element were used as sources of radiation.
As shown in Figs. 1 to 3, the interference of perchloric acid could be observed even in concentrations below 10^-310^-4M. Perchloric acid increased the absorption of magnesium, calcium, molybdenum, chromium and vanadium in an air-acetylene flame, on the other hand, it decreased the absorption of iron, nickel and cobalt.
Perchloric acid increased the absorption of magnesium, calcium and chromium in an air-hydrogen flame, and it also increased the absorption of molybdenum and vanadium in a nitrous oxide-acetylene flame.
As shown in Figs. 4 to 9, it has been found that the interferences of perchloric acid were greatly affected by the change of the fuel gas flow rate (pressure) as well as burner height. Perchloric acid generally gave relatively strong effects on the elements at the lower parts of the fuel-rich flame.
As shown in Fig. 10, such interferences could be also observed in the use of perchlorates such as sodium perchlorate and ammonium perchlorate. But coexisting cations had a strong influence on the results.
And such interferences were found to be peculiar to perchlorate ion, they were not observed with chloride ion, chlorate ion and hypochlorate ion.

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The interference of the twenty-four water-soluble organic compounds in atomic absorption spectrophotometry of calcium in an air-acetylene flame was studied.
A Nippon Jarrell-Ash model AA-1 atomic absorption/flame emission spectrophotometer and a slit burner (slit width 0.5×100mm) were used. A hollow cathode lamp of calcium(Westinghouse) was used as a source of radiation.
The interference of the water-soluble organic compounds on calcium were observed the concentration in the order of 100 ppm. Such interferences were found to be greatly different from each other depending on the concentrations and on the types of the compounds.
Some examples of these interferences caused by the water-soluble organic compounds were as follows and their values were expressed by the relative absorbance.
Glucose: 1.22, Ascorbic acid: 1.24, EDTA: 1.82, Ethylene glycol: 1.49, Ethanolamine: 1.38, Pyruvic acid: 1.31, Tartaric acid: 0.85, Glycolic acid: 0.88.
The method of controlling the interference caused by the water-soluble organic compounds was studied by an addition of a compound which yields an intensive enhancement interference on calcium.
As the results, it was found that ammonium perchlorate gave an intensive enhancement interference on calcium. The interference of ammonium perchlorate was stronger than that of the water-soluble organic compounds. Accordingly, the interference of the water-soluble organic compounds on calcium can be controlled by an addition of ammonium perchlorate.
The exact quantitative analysis of calcium containing some water-soluble organic compounds was made by atomic absorption spectrophotometry in an air-acetylene flame, provided that the ammonium perchlorate was added in the sample solution and standard solution of calcium in equal concentration.

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As a part of mass spectrometric study of metal chelates, the authors attempted to apply mass spectrometry to the qualitative analysis of 5-chloro-7-iodo-8-quinolinol (chinoform) metal chelates (Fe, Co, Ni, Cu, Zn).
Mass spectra were measured with a Hitachi RMU-7 mass spectrometer according to the direct inlet system under the following conditions: ionizing voltage 70 eV, ion accelerating voltage 1800 V, total emission current 80 μA, ion source temperature 250°C, and sample evaporating temperature 180250°C.
In the case of Fe(III) chelate, the peak being attributable to the molecular ion was observed, and the mass units corresponded to a 3 : 1 molar ratio chelate. The loss of 304 mass units from the molecular ion was observed and it indicated a cleavage of one molecule of the coordinated chinoform from the molecular ion to afford the fragment ion of a 2 : 1 ratio chelate. The loss of 304 mass units from the 2 : 1 chelate occurred successively to afford the fragment ion of a 1 : 1 ratio chelate. Simultaneously another fragmentation of the subsequent loss of the iodine atom from the 2 : 1 chelate was observed.
In the case of Co(II), Ni(II), Cu(II), and Zn(II) chelates, the molecular ion peaks corresponding to metal chelates of a 2 : 1 ratio, were observed in every spectrum. The loss of 304 mass units, corresponding to one molecule of coordinated chinoform from the molecular ion occurred to afford the fragment ion of a 1 : 1 ratio metal chelates. On the other hand, another fragmentation of the loss of the iodine atoms from the molecular ion was observed, simultaneously.
It has been disclosed qualitatively that mass spectrometry will be one of the useful and effective methods to know, 1) whether chinoform forms metal chelate or not, 2) what kind of metals are participating in the chelate formation, and 3) what is the binding ratio of the chinoform metal chelates in the living body.
In conclusion, the mass spectrometric method gives a useful information about the fate of chinoform in the living body of the SMON patients by detecting metal linkages directly in the biological specimens, such as feces, urine, body fluid, blood, and tongue fur.

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The method of rapid determination of arsenic in steel was studied. This method is based on chemical conversion of arsenic to arsine by reducing agent and sweeping of arsine evolved into an argon-hydrogen flame of an atomic absorption spectrophotometer by means of argon carrier gas. Sample was dissolved in aqua resia with heating gently. The solution was concentrated to 12ml, cooled, and diluted with 1.2 N hydrochloric acid to give a final concentration of 0.020.06 μg/ml arsenic. Twenty five ml of sample solution was put into a reaction vessel and added 0.5 ml of 20% stannous chloride solution and 1 ml of 20% potassium iodide solution. Ten minutes after the addition of reagent, the vessel was set to the new type arsine evolution kit (Nippon-Jarrell Ash Co., Ltd.) and added one tablet of mixture of zinc powder and binder, and quickly covered tightly with the plunger. When the pressure gauge shows 0.5 kg/cm², arsine evolved was carried into an argon-hydrogen flame. Arsenic in treated sample solution was determined within 1 minute. Arsenic in standard samples of various steels were determined ranging from 90% to 100% of standard values.

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An automatic apparatus has been developed for determination of sulfur in iron and steel by means of photometric titration after combustion with a high frequency induction furnace. The apparatus consists of a absorption bulb, a detector, a syringe for titration, a digital counter, a sample exchanger, and the high frequency induction furnace, and they are controlled by a sequence controller using relays and a timer. The schematic diagram of the developed analyzer is shown in Fig. 6.
A device based on the theory of spray was adopted in the absorption bulb in order to increase absorbing efficiency and wash the inner wall of conduit tube by circulation of absorbing solution. A dust filter of jet type was attached to the combustion tube to remove fine dust. They are shown in Fig. 1.
Samples are weighed, put into porcelain crucibles with flux, and the crucibles are placed manually on the turn-table of a sample auto-exchanger in Fig. 5. If a start-button is pushed, all the analytical procedures (combustion, titration, exchange of samples, printing out of counts for titration etc.) are performed automatically according to the program as shown in Fig. 7. After completion of analysis of whole samples, the contents is calculated by the formula a×b×100/w manually, where a is quantity (g) of sulfur corresponding to 1 count obtained from the standard samples, b is counts for unknown samples and w is weight (g) of unknown samples.
The lower limit of determination was 0.005% and time required for analysis of one sample was about 6 minutes. Coefficient of variation is low than 5% and the analytical results were well agreed with those by the manual work. The present apparatus can be easily connected with an electronic computer and controlled by it.

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A method for determining thiophenic-compounds by means of reaction gas chromatography in conjunction with a sulfide ion-selective electrode detector has been developed.
Components in the sample are separated on a gaschromatographic column using hydrogen as carrier gas.The effluent is passed through postcolumn reactor at 900°C where the separated components undergo hydrogenolysis in the presence of a platinum catalyst. Hydrogen sulfide is formed from sulfur compounds. The decomposition gases are introduced into an absorption tube in which a suitable absorption solution flows at a constant flow rate and hydrogen sulfide is absorbed by the absorption solution. The solution emerging from the absorption tube is passed into a micro-cell equipped with a sulfide ion-selective electrode as the sensing element. Changes in the sulfide ion concentration in the solution are detected by the corresponding changes in the ion electrode potential. The difference in the potential between the ion electrode and the reference electrode is fed to an antilog converter circuit and a signal directly proportional to the ion concentration is recorded. A chromatogram showing only peaks due to sulfur compounds is obtained.
In this method, the effect of temperature on the hydrogenolysis reaction was investigated. Nonthiophenic compounds decomposed nearly completely at all temperatures down to at least 700°C. Although aromatic sulfides were relatively resistant to hydrogenolysis, more than 30% of diphenyl sulfide and diphenyl disulfide were still decomposed at 700°C. On the other hand, thiophenic compounds are unreactive up to 700°C and decompose only slightly at 750°C. Consequently, when the temperature of postcolumn reactor where each component undergoes hydrogenolysis is maintained at 900°C, a chromatogram which peaks of all sulfur compounds are recorded is obtained. However, as the temperature is decreased, only the peaks due to thiophenic compounds decrease rapidly and a chromatogram which only the peaks due to thiophenic compounds are completely removed is obtained at 700°C. In this method, sulfur compounds can be easily distinguished from other compounds and thiophenic compounds can be readily identified from other sulfur compounds by comparing both chromatograms.

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The gas chromatographic analysis of the trace concentrations of sulfur compounds at the level of ppb or ppt in the urban air was studied.
The sample for the gas chromatographic analysis was prepared by the direct cold trap method cooled with liquid oxygen, and then detected by the flame photometric detecter.
Four sulfur compounds, i.e. hydrogen sulfide, carbonyl sulfide, sulfur dioxide and carbon disulfide were identified with the use of TCP and TCEP columns. One month's survey (Apr. 5Apr. 30, 1974, 100 samples) showed that the detected concentration ranges and average values of the four sulfur compounds were as follows: hydrogen sulfide 0.524 ppb (av. 2.4 ppb), carbonyl sulfide 0.42.9 ppb(av. 1.2 ppb), sulfur dioxide 2.080 ppb (av. 22 ppb) and carbon disulfide 0.175 ppb (av. 2.7 ppb), respectively.
The minimum detectable concentrations of the method were as follows: about 200 ppt for hydrogen sulfide and sulfur dioxide, about 50 ppt for carbonyl sulfide and carbon disulfide.

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N, N-Dimethylformamide reacts with selenium(IV) in hydrochloric acid and precipitates quantitatively metallic selenium after being heated in water bath at 100°C. The reaction was applied to the gravimetric determination of selenium(IV). Most of diverse ions do not interfere except tellurium(IV), but its interference can be masked by the addition of potassium sodium tartrate.
The recommended procedure is as follows: Weigh exactly the samples containing about 20300 mg of selenium(IV), and dissolve into 1020 ml of nitric acid with heating. After evaporating up to dryness, add 3 ml of hydrochloric acid (2 : 1) and 20 ml of N, N-dimethylformamide. Transfer the solution to a 100 ml stoppered Erlenmeyer-flask, and heat for 4 hours in boiling water to complete the precipitation.Then filter the precipitated selenium through a weighed sintered glass filter, and weigh after washing and dryness.
For the consecutive determination, silver(I), copper (II), and bismuth(III) in the filtrate can be determined gravimetrically(silver, as chloride), or complexometrically (copper and bismuth). Bismuth shows better results by back-titration with standard thorium nitrate solution.

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The fluorescence intensity of the chelate complex of Zn (II)-oxine-5-sulfonate is sensitized with the long-chain quaternary ammonium salt such as the zephiramine. By the use of this enhancement effect it is possible to increase the sensitivity of the fluorimetric determination of zinc. A fluorescent chelate complex of Zn(II)-oxine-5-sulfonate has its maximum emission at 526 nm with an excitation at 362 nm. As shown in figure 1, the addition of the quaternary ammonium salt produced a spectral shift of about 30 nm to longer wavelength in the excitation maximum and about threefold increase in the fluorescence intensity at the maximal.
The fluorescence intensity and maximum wavelength of excitation of Zn(II)-oxine-5-sulfonate changed monotonously with decreasing the dielectric constant in dioxane-water mixtures. This suggests the large contribution of the “decreased dielectric constant” of micelle surface in water to the fluorescence enhancement. The addition of the zephiramine increased the fluorescence quantum efficiency of the complex from 0.022 to 0.042. The effect of diverse ions were examined with 2.0μg of Zn(II)/50 ml. The results are summarized in Table I. The ions, Mg(II), Sr(II), Ca(II), Ba(II), Cr(III), did not interfere. The ions, Cu(II), Co(II), Ni(II), completely quenched the fluorescence of the zinc chelate.

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A distillation-potentiometric titration method for the determination of traces of chlorine in zirconium and zircaloy has been developed. A vessel containing 0.5 g of sample, 3 ml of water, and 0.2 g of ammonium sulfate is connected with a distillation apparatus shown in Fig. 1. After addition of 15 ml of sulfuric acid-nitric acid mixture (100+1) to the vessel, the solution is heated and the sample is dissolved. During the dissolution of the sample, chlorine in the solution is distilled and carried with nitrogen stream to a receiver containing 10 ml of ethanol. After the distillation of chlorine is complete, the collected chlorine is titrated potentiometrically with mercury(I) nitrate solution.
As shown in Table I, 520 μg of chlorine added is recovered satisfactorily by the distillation from the sulfuric acid solution. The blank value throughout the entire procedure is 0.6 μg±0.1μg of chlorine.
When water is present with chlorine in the ethanol solution, the end point of the titration curve is not distinctly observed. Therefore, water distilled. from the sample solution is removed by using an absorbing tube containing concentrated sulfuric acid. Sulfide ions evolved in the course of the dissolution of the sample also give a positive error in the chlorine determination. The interference is, however, avoided by the addition of a small amount of nitric acid to sulfuric acid which is used for the sample dissolution.
The analytical method proposed is applied to the analysis for chlorine in zirconium (HP-I) and zircaloy (JAERI Z-I). The results obtained for JAERI Z-I are shown in Table II.

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Diastereoisomeric ketals of ketones were resolved by gas chromatography on a glass capillary column.
First, glass capillary(25 m long, 0.25 mm i.d.) was etched with dry hydrogen chloride at 230°C for 24 hours. After etched, chromic-sulfuric acid was passed through this capillary and washed with water and methanol. Glass capillary was coated with 0.1 ml of 15% (w/v) NPGS/methylene chloride solution containing 0.2% (w/v) benzyltriphenylphosphonium chloride by the dynamic coating method with nitrogen pressure at a linear coating velocity of 1 cm/sec. After the solution had passed through the column, nitrogen pressure was maintained for about 5 hours to dry the solvent off. The column was then conditioned for 15 hours at 210°C.
This column showed 58, 000 of HETP for diastereoiscmeric 3, 3, 5-trimethylcyclohexanone(Table I, 1st peak) without significant loss of efficiency after 100 hours of use at 190210°C.
Ketalic diastereoisomers were obtained by reacting each ketone with (+)-dimethyl tartrate or (+)-2, 3-butanediol in Dean-Stark apparatus.
When using (+)-dimethyl tartrate as a resolving reagent, sec-butylmethylketone, 3-methylcyclohexanone and 3, 3, 5-trimethylcyclohexanone were almost completely resolved and 2-methylcyclohexanone was partially resolved. And 2, 4, 4-trimethylcyclopentanone remained unresolved. When using (+)-2, 3-butanediol, however, 3-methylcyclohexanone, 2, 4, 4-trimethylcyclopentanone and 3, 3, 5-trimethylcyclohexanone were almost resolved, sec-butylmethylketone and 2-methylcyclohexanone were not resolved at all.
Diastereoisomeric ketals from (+)-dimethyl tartrate have greater-Δ(ΔG°) than from (+)-2, 3-butanediol except 2, 4, 4-trimethylcyclopentanone.

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[in Japanese]

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