An X-ray spectrochemical method was employed in the determination of organic solvent type preservatives, such as tributyl tin terephthalate (TBT-Te), copper naphthenate, and pentachlorophenol (PCP), impregnating timbers. The measurements were done on the specimens prepared into briquettes by pressing powdered samples. The relation between grain size distribution and wood species, and their effect on the reproducibility of spectral intensities were investigated. The precision depended on uniformity of samples rather than their grain size. Errors coming from the preparation of briquettes were, in the case of TBT-Te treated samples, 13% in beech and 23% in cedar.
Intensities of SnLα₁, CuKα and ClKα changed linearly with the contents of TBT-Te, copper naphthenate and PCP in wood, up to 1.5%, 6% and 2%, respectively. The proposed method was applied to the estimation of retention rate of the preservative solution in bamboo by the determination of TBT-Te contained. The error due to the difference in wood tissue was much reduced by briquetting, compaired with that in the non-destructive analysis.

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A spectrophotometric method with magnesium-Xylidyl Blue complex was applied to the determination magnesium in nickel used for electron tubes. The method is characterized by the elimination of interfering elements, such as nickel and trace of manganese, with mercury cathode electrolysis and subsequent solvent extraction.
The established procedure is as follows : -
In 20ml of nitric acid (1+1) and 4ml of perchloric acid is dissolved 0.10.2g of the sample, of which the amount depends on the magnesium content, and after heating the mixture on a sand bath to dense white fumes, nickel and other interfering elements are removed by mercury cathode electrolysis and subsequent solvent extraction. The aqueous solution is then evaporated to dryness on a heater in order to expel ammonium chloride and to decompose diethyldithiocarbamate. The residues are dissolved in hot water, and the solution is diluted to 100ml with water. To a 10ml portion of the solution is added 5ml of 0.03% Xylidyl Blue alcohol solution, and then 2ml of 0.08M sodium borate buffer solution. The final mixture is diluted with water to 50ml.
After allowing the solution to stand for 20 minutes, photometric measurement at 520mμ is carried out against a reagent blank.
The method is suitable for the determination of magnesium less than 0.1% of in nickel metal.

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A rapid spectrophotometric method with manganese (III) -pyrophosphate was applied to the determination of manganese in manganese magnesium ferrite.
The established procedure is as follows : -
In 30ml of phosphoric acid is dissolved 0.5g of the ferrite sample, and the solution is diluted to 100ml with water.
To a 20ml of sample solution is added 100ml of phosphoric acid to make the pH lower than 1. Manganese is oxidized with 8ml of 6% potassium bromate solution after adding 30ml of 0.5M potassium pyrophosphate solution, and the mixture is diluted to 100ml with water.
The absorbance at 520mμ of the solution is measured spectrophotometrically against the reagent blank.
The time required for an analysis was about 20 minutes.

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About 0.5g of the sample was decomposed with a mixture of HF and HNO₃. After having been converted to the chlorides, the residue was dissolved in water and the solution was diluted to 25ml.
The apparatus used were a Hitachi Spectrophotometer 139 with its atomic absorption attachment 139-0420 for the determination of ppm order of nickel, and the same spectrophotometer with a long path flame adaptor for 0.11.0ppm of Ni. The air-acetylene flame was used for the former, and the air-hydrogen mixture for the latter.
The spectrum line employed was Ni 2320Å.
The effects of the hollow cathode lamp current, slit width of the photometer and the burner height on the absorbance of Ni were examined. Virtually no effect was observed of the major elements and various acids in their usual concentration range.
The accuracy and recovery by the use of various kinds of glasses and the NBS standards were satisfactory for practical purposes.
The results obtained agreed well with those by other methods including emission spectrographic methods

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Hexyl-H (2, 4, 6, 2', 4', 6'-Hexanitrodiphenylamine) reacts with potassium ion to form water-insoluble precipitate which can be extracted into nitrobenzene. This has been applied to the determination of potassium in river water.
Potassium in aqueous phase (2.5×10^-5M, 500ml) is extracted into nitrobenzene (50ml) containing Hexyl-Na, the concentration of which is 0.02M. Then the organic phase (40ml) is shaken with 10ml of hydrochloric acid (pH =1). In these procedures, potassium is enriched as forty times that in the initial solution. The back-extracted potassium is precipitated with an excess of TPB-Na (sodium tetraphenylborate), and after filtration the excess of the reagent is back-titrated with a quarternary ammonium salts (tetradecyldimethylbenzylammonium chloride), Titan Yellow being used as an indicator.
In this titrimetry, potassium, such as 0.7×10^-32×10^-3M, could be determined within an error of ±0.04×10^-3M. By using the above-mentioned procedure, potassium, such as 2×10^-55×10^-5M, was determined within ±4% in the relative error.
This method could be applied satisfactorily to the determination of potassium in river water and tap water.

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A method for the atomic absorption spectrophotometric determination of zinc in lubricating oil was established.
Zinc in lubricating oil can be determined by atomic absorption measurement after diluting the sample oil with methyl isobutyl ketone. Calibrating solutions can be prepared by dissolving commercially available sp. grade zinc nitrate in methyl isobutyl ketone, which contains appropriate amount of liquid paraffin as the substitute for lubricating oil for adjustment of viscosity of the solution. In practice, however, a standard addition method was preferred for the determination.
The recommended conditions were : wavelength 2138 Å, hollow cathode lamp current 30mA, slit width 0.06mm, air pressure 1.2kg/cm², and propane pressure 0.04kg/cm².
The method is rapid and has accuracies nearly comparable to those attained by the conventional ashing method followed by polarographic or EDTA-titration.

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A new coulometric titration method for determining fluoride was developed. Aluminum ion is coulometrically dissoluted from a pure aluminum metal electrode to form the complex with fluoride ion in 0.5M deoxygenated acetic acid solution, and the end point is potentiometrically detected using a rotational beryllium electrode at 600rpm. The standard deviation of this mothod was 2.3% for 2mg of fluorine, and the lower limit of detection by this method was 4ppm. The anodic dissolution current was ordinarily 40.20mA.
Polarization characteristics of the rotating beryllium electrode were investigated in absence or existence of fluoride. The equilibrium potential was ca. -0.5V (vs. SCE) in the 0.5M acetic acid solution, and it changed to ca. -1.1V after an addition of fluoride. The polarization curves of the electrode showed characteristic hysteresis even in the existence of fluoride at the anodic side of polarization.
Amperometric end point determination was endeavored by the beryllium electrode, but the method was not superior to the potentiometric method.

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There is a difference between the electrolysis potential of mercury (II) -DTPA complex and that in adding a metal ion to the complex. This difference depends on the stability constant of the complex made of the metal ion and DTPA. So it would be possible to determine some metal ions, if a suitable potential has been fixed. This report deals with a controlled potential coulometric method for determining copper and zinc ions which form stable complexes with DTPA, and calcium ion which forms a less stable complex. Mercury-coated platinum was used as the working electrode. In 0.1M ammonia-ammonium nitrate electrolyte (pH=10) and at-0.05V vs. SCE, these ions in about 1 mg of the samples were determined with good accuracies.

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A high-sensitive and rapid cathode ray polarography was applied to the determination of traces of lead and zinc in iron and steels, whereby the optimum supporting electrolyte, treatment of sample after removal of iron, and influenece of diverse elements, the peak potentials were investigated.
In the recommended procedure, the sample is dissolved with hydrochloric acid and nitric acid, and evaporated to dryness. The residue is dissolved in 5N hydrochloric acid, iron is removed by MIBK extraction, and a portion of zinc escaping in the organic layer is back-extracted into 6N hydrochloric acid to be combined with the aqueous layer. The combined solution is then evaporated to dryness with perchloric acid and nitric acid to destroy MIBK. The last procedure is repeated three times. After cooling and an addition of 0.5M phosphoric acid as the supporting electrolyte and gelatin, wave heights at peak potentials are measured at-0.52V and-1.17V vs. S.C.E., respectively, for lead and zinc. As little as about 0.00x% of lead and zinc in both synthetic and practical samples could be determined. with variation coefficients 11.3% and 15.1 %, respectively.

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The separation of isomers of naphthylaminedisulfonic acids by salting-out chromatography, in which cation exchange resins are used as the stationary phase and concentrated acidic calcium chloride solution as the mobile phase, has been investigated.
Studies on the adsorption behaviors of the acids on weakly acidic resins showed that the distribution coefficients increased with increasing calcium chloride concentration, and that they were at maxima at pH of 2.53.5 : they decreased either at higher or lower pH values. The same tendency was observed also on the strongly acidic resins, but the separation factors, were larger than on the weakly acidic resins. The separations were achieved successfully when a mixture of amino-R and amino-G, amino-R and amino-C or amino-R and amino-J acids was eluted at 40°C through a column of φ17mm×450mm of Amberlite CG-120 with 3M calcium chloride solution of pH 2.9. The determination of the acids in the effluents by u.v. spectrophotometry proved the almost quantitative recovery of the acids.

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The investigation was carried out on an attempt to reveal the infrared absorption spectra due to polymorphism on three cardiotonic digitalis glucosides, digitoxin, digoxin and gitoxin. The results indicated that these glucosides had respectively two polymorphs.
One of polymorphic crystals of digitoxin was obtained by recrystallization from 85% ethanol and the other from cold ethanol evaporation, but the difference in the spectrum reported by Hayden et al. could not be observed.
One of digoxin was obtained by recrystallization from 85% ethanol and the other from cold methanol evaporation. The spectrum of the former was identified with that of J. P. Reference Standard and of the latter with that of U. S. P. Reference Standard or B. P. Authentic Specimen of digoxin. The former was changed into the latter by heating. The crystal reported by Mesley et al.could not be obtained in the author's experiment.
One of gitoxin was obtained by recrystallization from methanol-chloroform (1 : 1), and the other from hot evaporation of the methanol-chloroform (1 : 3) solution. The transition of the former into the latter was complete by heating at 110°C for 4 hours.

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Benzothiazolylazonaphthols (I) - (III) were synthesized, and their acid dissociation and reactions with metal ions were investigated.
It was revealed by visible and infrared absorption spectra that the equilibrium of azo form (III_a) and hydrazone from (III_b) of p-BNT (III) in chloroform shifted greatly on the (III_b) side.
α-BNT was superior than BNT in its high sensitivity and distinctness of color change.
Their chelates were extracted into organic solvents, and had 1 : 2 (metal : reagent) composition. The molar extinction coefficients of the chelates were large, e.g., 7×10⁴ in Zn-α-BNT. The compounds were applied satisfactorily to the spectrophotometric determination of metals.

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Chromazurol S reacts with Al in the presence of cetyl trimethylammonium chloride to form a blue ternary chelate. Its absorption maximum varies continuously with pH and reagent concentration. But absorbance at 620mμ is constant at pH 5.86.0 and obeys Beer's law over 0.010.08μg Al/ml. The sensitivity is very high since the molar extinction coefficient is 1.08×10⁵.
Be, Ga, Ti, Th, U, V, Zr, Cu, Fe, Cr, Sn and Ta interfere remarkably, but Cu and Fe (II) can be masked by ο-phenanthroline.

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Fractional to 5μg of gold, silver and mercury are collected on a sheet (7cm in diameter) of reagent paper impregnated with a few mg of a water-insoluble organic reagent, by a single or repeated filtration of a sample solution (10250ml, acidity 0.10.5N) at the flow rate of about 6ml/min. The recoveries of the metals (after ashing of the paper except for mercury) are usually about 98%. The effects of flow rate, number of filtrations, total quantity of metals, solution volume, acidity and coexisting elements on recovery of the metals are studied. This simple and rapid technique is successfully applied to the separation of low ppm of gold, silver and mercury in copper and lead matrices, the concentration factor of silver with respect to copper being approximately 2×10^-3. The reagent paper, which is prepared by treating filter paper with 1% (w/v) dithizone-chloroform or 0.05% (w/v) p-dimethylaminobenzylidenerhodanineacetone solution followed by 0.1N nitric acid, can be stored for over 80 days without any deterioration.

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Photometric determination of 0.01 to about 5 per cent of aluminum in ferrovanadium, ferrotitanium, ferrozirconium and ferroniobium with stilbazo has been studied. The aluminum-stilbazo complex showed an absorption maximum at 495mμ with constant absorbance at pH range from 4.3 to 6.0, and Beer's law was obeyed up to 50μg of aluminum when 2.5 ml of stilbazo solution (0.08w/v%) was used. The established method is as follows. In cases of ferrovanadium and ferrotitanium, 0.1 to 0.5g of sample is decomposed by treating with hydrochloric-nitric acid. In cases of ferrozirconium and ferroniobium, samples are decomposed by treating with nitric-hydrofluoric acid, and is evaporated with sulfuric acid to strong fumes until hydrofluoric acid has been removed. After being cooled, the interfering vanadium, titanium, zirconium, niobium and iron are removed by extraction with cupferron-chloroform in the presence of 3.5 N hydrochloric acid. The acidity of the solution is adjusted to pH about 5 with ammonia water (1+1) and hydrochloric acid (1+1) using p-nitrophenol as an indicator. One ml of ascorbic acid solution (5w/v%), 10ml of the buffer solution (pH 5.60) and 2.5ml of stilbazo solution (0.08w/v%) are added, and the mixture is made up exactly to 50ml with water. The absorbance is measured at 495mμ against reagent blank.
The proposed method has advantages over the JIS method, i.e., the higher precision, the rapid and simpler procedure. The time required for an analysis is about 50 minites.

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The behaviors of nanogram level of alkyl mercuric compounds including RHgX and RHgR (where R =alkyls and X=anionic groups) on gas chromatography have been studied. As the gas chromatographic columns were employed polydiethyleneglycol succinate 5% coated on Chromosorb W being packed in a stainless steel tubing (I) and the same liquid phase 1% coated on the rock crystal powder packed in a glass tubing (II), and they were maintained at 140°C150°C. When the column (I) was used, RHgX (X=I, Br, Cl) and RHgR were separated fairly well at the sample size above 10^-5g. Below 10^-8g, however, the compounds which had the same R group showed the same retention times regardless of difference in X groups (X=I, Br, Cl, CH₃CO₂, SO₄, OH and dithizonate). These phenomena were not observed when the column (II) was used. Micro amounts of alkyl mercuric compounds are supposed to be thermally decomposed in the gas chromatographic column by catalytic action of column-composing materials (e.g. stainless steel, porous substrates). At the sample size of more than 10^-5g, where the thermal conductivity detector is used, the major portion of injected sample passes through the column without suffering from thermal decomposition and give characteristic retention times. In this case, decomposed micro portions are not detectable. Decreasing the sample size below 10^-8g, injected samples are completely decomposed and resulting products are detected by an electron capture detector. Though the mechanism of the decomposition has not been clear, it is assumed that a reaction that destroys the X group occurs in the column (I), forming another compound indifferent to X group.

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The stable isotope dilution technique has been applied to the determination of hafnium in some of the samples of Zircaloy. Hafnium in the sample was separated by anion exchange chromatography eluted with dilute sulfuric acid. A surface ionization type mass spectrometer (CEC 21-702 B) was used with tungsten ribbon triple filaments for hafnium isotope analysis. Hafnium is determined within a relative error of several percent in the range from 40 to 500 ppm. The results obtained were discussed comparing with those measured by other methods.

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Various examinations on the quality of phenylfluorone used in colorimetric analysis of tin or germanium were made. This paper deals with a method of purification of the reagents being sold in the market.
Comparative studies were made on the differences of appearences, linearity of the calibration curves in colorimetric analysis of tin, and of stability against time and light, etc., of seven samples of phenylfluorone, including the one synthesized in our laboratory.
It was found that the quality of phenylfluorone might be improved by removing impurities with hot ethanol extraction, and that the stabilities against time and light increased as the purity increased.
In the colorimetric analysis of tin or germanium, it will be recommendable to measure phenylfluorone at 470mμ with a molecular extinction coefficient of more than 4×10⁴.

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An investigation of the fundamental conditions for the photometric quantitative determination of phenothiazine with ferric chloride was made, and it was found to follow the Beer's law in the concentration range of 220 μg/ ml within 2% error by the examination of reproducibility.
The reaction products isolated are considered to be phenothiazine-3-one, the oxidized product of phenothiazine, from its physical properties.
Various phenothiazine derivatives used as medicinal drugs show the similar coloration with ferric chloride and therefore this method may be applicable to the photometric determination of phenothiazine derivatives.

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The steam carrier adsorption gas chromatography may be applicable to the analysis of polyalcohols, fatty acids, phenols and amines.
A crushed insulating firebrick (SiO₂ 50%; Al₂O₃ 45%; and others), modified by potassium fluoride for diols, or added further a little phosphoric acid for glycerol, being packed in a glass column, serves as adsorbents, through which steam may carry these materials separately without remarkable tailing at comparatively low temperature (130°C), even an aqueous sample being separable.
The separation columns for fatty acids up to C₁₈, phenol, cresol and alkyl-phenols by steam carrier without any troubles are prepared by heating at 500 °C a glass column containing firebrick powder to which 13% phosphoric acid is absorbed. These columns can be detectable at the concentration lower than 1 ppm aqueous solution of low fatty acids and phenols, by a hydrogen flame ionization detector. To use these acidic columns, alkaline metal salts of fatty acids show the similar figure of chromatogram to the free acids.
Amines can be eluted fractionally through the separation column of magnesia powder and an aluminum pipe with so little tailing that analysis of dilute aqueous samples of alkyl-amines, pyridine, aniline and their derivatives (including hydrogen chloride salts) is achieved.
These chromatographys are operated at 100°C to 230 °C.
This method might be expected to be applicable to more organic chemicals.

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A new method for the determination of a small amount of iodide by atomic absorption spectrophotometry with cadmium hollow cathod lamp is proposed. The method is based on solvent extraction of the colorless ion-pair formed between 1, 10-phenanthroline-cadmium (II) and iodide ion with nitrobenzene and the subsequent determination of the cadmium in the extract is made by atomic absorption at the 2288Å cadmium line.

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[in Japanese]

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[in Japanese]

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