Determination of impurity elements in steel by speak source mass spectrometry using powdered salts sample electrode was studied. The instrument used in this study was an AEI MS-7 mass spectrograph and the ion detector was Ilford Q2 photograph. Sample, (0.51) gram, was dissolved in hydrochloric acid (1:1) or nitric acid (1:1) together with yttrium of 1 microgram as the internal standard and then the solution was evaporated to dryness without baking. The salt residues were dried at 70°C for 30 minutes under vacuum. They were mixed with an equal amount of graphite powder for 5 minutes in a mixer mill, and then pressed into electrodes.
When the relative sensitivity coefficient (Fe =1) was determined by using NBS 460 series standard samples, the results obtained by the proposed method for elements of Mo, Sn, Cu, Cr, Co, Ni, Mn, V, P, Si, and B were in good agreement with those obtained. by the conventional method using solid sample electrodes (the solid method) and the precision of this method for 11 elements mentioned above was about 10% better than those of the solid method. However, both the accuracy and precision for elements of Nb, Ti, S and W were not good. This method was applied to the determination of impurities in NBS stainless steel and others. The relative standard deviations were within 20%.

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The present work was undertaken to elucidate the effect of chloride ion on the COD determination with potassium dichromate. The COD value was determined by JIS method. Kraft pulp mill black liquor, its waste water effluent, municipal waste water influent, and its effluent were used as samples.
The results are as follows;
(1) The COD determination method with potassium dichromate as described in JIS was influenced by chloride ion.
(2) The COD values of all given samples increased with the increment of the concentration of chloride ion. The extent of the increment of the COD value varied with the concentration of sample and species of samples.
(3) In the presence of chloride ion, a linear relationship between the COD value and the dilution ratio of sample was not observed.
(4) The increment of the COD value (ΔCOD) resulted by the oxidation of chloride ion increased with the decrement of the concentration of sample.
(5) Mercuric sulfate could not suppress the oxidation of chloride ion in spite of its further addition, twice to three times as much as the quantity described in JIS.

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Uranium in uranyl nitrate, uranium trioxide and a high-purity uranium metal was assayed by the coulometric titration with biamperometric end-point detection. Uranium (VI) was reduced to uranium (IV) by solid bismuth amalgam in 5 M sulfuric acid solution. The reduced uranium was reoxidized to uranium (VI) with a large excess of ferric ion at a room temperature, and the ferrous ion produced was titrated with the electrogenerated manganese (III) fluoride. In the analyses of uranium nitrate and uranium trioxide, the results were precise enough when the error from uncertainty in water content in the samples was considered. The standard sample of pure uranium metal ( JAERI-U4) was assayed by the proposed method. The sample was cut into small chips of about 0.2 g. Oxides on the metal surface were removed by the procedure shown by National Bureau of Standards just before weighing. The mean assay value of eleven determinations corrected for 3 ppm of iron was (99.998±0.012) % (the 95% confidence interval for the mean), with a standard deviation of 0.018%. The proposed coulometric method is simple and permits accurate and precise determination of uranium which is matrix constituent in a sample.

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Microgram amounts of mercury was determined by a technique combined with solvent extraction and subsequent X-ray fluorescence measurement. The specimen was prepared by extracting mercury (II) into dithizone-chloroform, dropping the extract wholly on a filter paper with continuous blow of warm air and by concentrating the dispersing chelate quantitatively into a definite area most intensely excited by X-ray beam by permeation with chloroform from hem of the paper.
A tungsten target X-ray tube was used for excitation of mercury in the specimen, and the intensity of HgL_α1 line emitted was measured. In this case, HgL_α1 line is overlapped by a scattered WL_β2 line so that the intensity of background (I_BG) was calculated by the equation obtained experimentally, that is, I_BG=1.10 ×I_WLγ1, where the intensity of a scattered WL_γ1line (I_WLγ1)is given by measuring for every specimen. HgL_β1 line as well as HgL_α1 line gave a satisfactory result, though its intensity was poor.
Three and 30 micrograms of mercury could be determined with 9 and 1 per-cent of variation coefficient, respectively. Problems, such as the effects of coexisting elements : silver (I), gold (III), copper (II), etc, and the extent of permeation-concentration of mercury into the area described above, were discussed.

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A new method for the collection of trace concentration of hydrogen cyanide in air was studied for the purpose of economizing the sampling time. Hydrogen cyanide was captured reacting with the reagent coated on a filter.
Alkali and nickel salts were examined as the coating reagent. The most suitable filter for collection is prepared as follows. The filter ordinarily used for aerosol collection was dipped in an aqueous solution of ammoniacal nickel chloride (or nitrate). Then it was air-dried and stored in a desiccator which had been saturated with ammonia gas just before its use.
The collection efficiency depended on the volume of sample air and was more than 95% when the air containing (5200) ppb hydrogen cyanide was led at a velosity of 5 meters per minute. It was hardly affected by variations of temperature and humidity and by the presence of sulfur dioxide or nitrogen dioxide in the concentration of the order of urban atmosphere.
The recovery of hydrogen cyanide of ppb order ranged from 90 to 100%, when the sample air was led to the filter at flow rate of 200 liters per minute for 20 minutes using high volume air sampler with sampling area of 400 cm².

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The Fourier transform spectrometer system for high frequency range has been constracted. It showed super beneficial function over the dispersion spectrometer. The composition of the system consists of the optical interferometer, the electric data handling equipment and the computational component. The optical part was comprised principally of a birefringent interferometer. The soleil compensator prism was moved continuously by about 30 mm in a time 0.5, 1.0 or 2.0 s, producing the optical difference of 110 μm at 7000 cm^-1 and 140μm at 25000cm^-1. The spectral resolution was better than 60 cm^-1 at 5800 cm^-1 without apodization. The data handling equipment was formed of the following components, the control circuit for the starting position of the data sampling, the A/D convertor, the interface, the signal storaging and averaging, and a tape puncher and an X-T recorder for the readout of the interferogram. The data handling was carried out by a Hitachi Model 1600 signal averager with 1600 words core memory. During a scan of the compensator prism, the signal from the detector was digitalized at a sampling rate of 800 Hz and presented as a sequence of numbers. A chosen number of multiple scans were added together in the system and the result was averaged in each scan. By this procedure, the signal-to-noise ratio was much enhanced. After it was confirmed that the difference of the optical path between the -1st and the +1st data was less than 1%, the stored interferogram was transformed into two charactor presentation though a parallel-serial convertor and punched out on a paper tape. The tape was then fed to a FACOM 270-30 computor, and computed for apodization, F. T., correction for dispersion effect and some more additional data treatment. The results of the computation were converted to analog data and fed to an X-Y plotter to give the spectrum. The discrete F. T. was used for the spectrum resolution better than 100 cm^-1 and the fast F. T. for the resolution less than 100 cm^-1 in the computation. Owing to the high efficiency of the optical system and high sensibility of the signal-to-noise ratio, the spectra of low energies, e. g. the emission spectrum of the moleculer viblational overtone of thermal exited oleic acid at 150°C and the near infrared absorption spectra of rare earth elements which was superposed on the absorption of water were effectively separated from the background by the multiple scanning measurements.

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A gas sampling system has been developed for the analysis of the pyrolysis and the combustion products of polymer materials. Gases produced are collected in the cold trap of a glass tubing (4 mm ID) packed with porous polymer beads in 2 cm length. Porapak Q is the best suited as a packing material. Gas retention ability of the trap is measured at temperatures of liquid nitrogen and dry ice-acetone. CO, CO₂, CH₄, C₂H₂, C₂H₄, C₂H₆, HCl and NH₃ pass through the trap at the dry ice-acetone temperature. At the liquid nitrogen temperature, however, these gases are retained in the trap completely for more than several minutes. H₂S, HCN and organic gases with more than 3 carbon atoms are retained in the trap at the dry ice-acetone temperature. Thus serial combination of these traps enable to collect gases fractionally from the pyrolysis or the combustion. On heating the traps, the collected constituents are released almost quantitatively. Capability of this sampling system is demonstrated by analyzing combustion gas from polyethylene.

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The magnetic circular dichroism (MCD) spectra of 30 mono-substituted naphthalenes were measured for the ¹L_b and ¹L_a absorption bands. It is demonstrated that these spectra can be classified into three groups, and that the sign of the MCD for the ¹L_b band is negative if the compound has a donor group and is positive if it has an acceptor group, and that the magnetic rotational strengths are larger for the 1-than for the 2-substituted naphthalenes. This remarkable feature is interpreted in terms of the energy difference between the ¹L_b and ¹L_a states and the angle between the electric dipole moments induced by the two transitions, assuming that the mixing of the above two states is dominant in the MCD in these cases. Using the above-mentioned observation, the MCD spectra can be used in analytical chemistry to identify the isomers of mono-substituted naphthalenes and to determine the kinds and characteristics of the substituents.

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A new chelating cellulose ion-exchanger containing carboxyl and hydroxamic acid groups was synthesized as follows : liquid nitrogen dioxide was introduced into a flask containing cellulose powder and the mixture was stirred for (6067) h at room temperature. The oxidized cellulose (C-cell) was then mixed with an ethanolic hydroxylamine solution, in which the molar ratio of hydroxylamine to carboxyl group was kept at 10 to 1, and allowed to stand for 60 h at room temperature. The crude hydroxamized cellulose (H-cell) was washed with a dilute hydrochloric acid (pH 3)-ethanol mixture (1 : 1) repeatedly. As was expected, the H-cell reacted similarly with iron (III) ions to benzo- and salicylhydroxamic acid. The uptake of iron (III) ions on the H-cell increased sharply between pH 2 and 3, and became nearly constant at pH 3. In addition, iron (III) ions collected on the H-cell could be easily extracted into dilute hydrochloric acid (pH 2) containing small amounts of ascorbic acid, the recovery being almost quantitative. The H-cell exhibited higher affinity for iron (III) ions than the C-cell in 1M sodium chloride solution. Hence, the H-cell was proved to be useful for the selective collection of iron (III) from sea water.

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Amino acids and amino sugars react with pyridoxal in pyridine-methanol solution to yield their Schiff's bases which give blue fluorescence by the addition of zinc(II) ion. The properties of fluorescent complexes formed in the reaction mixture were investigated by spectroscopically. The fluorescent complex was composed of pyridoxal, amino acid (or amino sugar) and zinc (II) ion (1 : 1 : 1). Salicylaldehyde, instead of pyridoxal, was used as model compound in the synthesis of complexes. The (1 : 1) and (2 : 1) complexes were obtained from N-salicylidene glucosamine and N-salicylidene 2-amino-1-butanol, respectively. N-Salicylidene glucosamine or N-salicylidene 2-amino-1-butanol worked as tridentate and bidentate ligand, and formed white (1 : 1) complex and yellow (2 : 1) complex with zinc (II) ion. The fluorescence of (1 : 1) complex was stronger than that of (2 : 1) complex. N-Salicylidene leucine worked as tridentate ligand, and formed white and yellow (1 : 1) complexes with zinc (II) ion. The white complex was highly fluorescent and soluble in methanol, while the yellow one gave no fluorescence and was almost insoluble in methanol. From the above result, it was concluded that the fluorophor of this fluorescence reaction was (1 : 1) complex of N-pyridoxylidene amino acid or N-pyridoxylidene amino sugar with zinc (II) ion.

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Although the flameless atomic absorption spectrophotometry is common in the determination of mercury, concentration of mercury in natural waters is generally so low that the atomic spectrometry cannot be directly applied to such a sample. A nanogram amount of mercury in waters can be accurately determined by the flameless atomic absorption technique after pre-concentration of mercury on silver metal particles (Fig. 1). Mercury in a sample water is completely collected on (0.31) g of silver metal (Fig. 2) at nitrogen flow rates of (0.91.4)1/min.The effects of temperature of the furnace (Fig. 4) and time interval before the start of nitrogen flow (Fig. 3) were examined. Temperature of the reaction vessel can be varied in the range from 5°C to 30°C. but the temperature must be slightly lower than that of the silver metal because water condensed on the silver gives a positive error.
The following procedure is recommended. Add 2 ml of 6% SnCl₂·2H₂O solution to (0.51)l of sample water which has been acidified to 0.4 N with H₂SO₄ immediately after sampling and allowed to stand for more than 3 weeks. Pass nitrogen for more than 5 min at a flow rate of 1.2 l/min. Collect the vaporized mercury on 0.5 g porous silver metal particles packed in a small glass tube. Place the silver in an electric furnace whose temperature has been kept at 500°C. After 2 min, pass nitrogen at a flow rate of 1.5 l/min, and record the absorbance at 254 nm. A sharp peak is obtained. The coefficient of variation is 10% for 5 ng of mercury.

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A method for the back-extraction of metal complexes in methylisobutyl ketone (MIBK) by its dilution with hexane is proposed on the basis of drastic decrease in the metal extraction into this solvent as a result of dilution with a nonpolar solvent.
Extraction and back-extraction of mercury (II) iodide and thallium (III) chloride complexes were demonstrated as examples. The metal ion was first extracted from the sodium halide solution into MIBK. Then a portion of this MIBK was diluted with a certain volume of hexane and was agitated with a solution of the same sodium halide. The distribution ratio of this back-extraction was calculated. The extraction was impaired very much by the dilution; dilution of one volume of MIBK with three volumes of hexane enabled back-extraction of more than 90% of the metal ion into one volume of the halide solution from which more than 99% of the metal ion was extracted into undiluted MIBK.
The statistical treatment of this back-extraction is given and the possibility of the use of this method for various metal ions is considered.

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Indole-α-pyrone was used by A. Stoessl and M. A.Venis for the purpose of fluorometric determination of IAA.
In this work, analytical conditions have been studied to improve their method. The following analytical procedure is recommended : An aqueous solution of 1 ml contained 5× 10^-51 × 10^-7 mol/l of IAA is taken in a test tube and dried in a vacuum desiccator at room temperature. Then 0.5 ml of mixture (1 + 1 by vol.) of caproic anhydride and boron trifluoride (BTF) is added into the tube. After standing for 15 min. at 0°C, 5 ml of KHCO₃(5% W/V) solution is added. After shaking, indolo-α-pyrone formed is extracted with 5 ml of n-butanol. The fluorescence is measured at 500 nm by using an excitation at 440 nm. By the proposed method, for intensity of the fluorescence is remarkably enhanced. This reaction depends on the catalytic action of Lewis acid. Interference by diverse indole compounds and inorganic ions was studied in mole ratio range from 10 to 100 times against 1 ml of IAA (5 × 10^-7 mol/l). In the determination of IAA, many indole compounds except 5-hydroxy-IAA and indole-3-acrylic acid did not interfere.

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When an acid solution is added to a mixed solution of IAA and formaldehyde, the solution fluoresces. The mixed solution in hydrochloric acid showed two excitation peaks at 330 nm and 380 nm, and only a single fluorescence peak at 490 nm. In this work, the optimum conditions, and interferences have been examined. From the result, the following analytical procedure is recommended : One ml of solution containing 1 × 10^-55 × 10^-7 mol/l of IAA and 1 ml of formalin (containing 37% formaldehyde) is added to 2 ml of 1N HCl. After standing for 45 min. at room temperature, the intensity of fluorescence at 490 nm (excited at 330 nm) is measured.
In this method, many kinds of diverse indole compounds interfered even in the same amount of IAA, while inorganic ions except Fe³⁺, Hg²⁺, and I^- did not interfere.
The calibration curve was linear in the range of about 1 × 10^-55 × 10^-7 mol/l {(1.80.1) μg/ml} of IAA.

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Basic studies were made of the spectrophotometric determination of aluminum using apigenin (5, 7, 4'- trihydroxyflavone), which had been proposed as a possible reagent by Nowicka-Jankowska et al. Chem. Anal. (Warsaw), 10, 129 (1965). Experimental emphases were put on the measurements of the maximum absorption wavelength, the optimum pH-value, the molar composition, the molar absorptivity and the stability of apigenin-aluminum complex in 50% (v/v) alcoholic medium.
Preceding experiments confirmed that ethanol was unsuitable as a solvent for the complex formation, and revealed also that the acetate-buffer-solution interferred (Fig. 1). The following results were thus obtained in 50% (v/v) methanolic media, the pH of which was adjusted with a dilute sodium hydroxide solution or with dilute hydrochloric acid;
(1) the maximum absorption wavelength; 388 nm
(2) the optimum pH value; 5.1 (Fig. 2)
(3) the molar composition; Al (apigenin)₂ (Fig. 3)
(4) the molar absorptivity; 26400 (388 nm, pH 5.1)
(5) the stability of the complex; No change of absorbance was observed even on keeping it for 24 hours at room temperature.
(6) The disadvantage of this reagent is the sensitive dependence of the absorbance of the complex on pH. (Fig. 2)

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Volatile and non-volatile organic acids in aqueous solution were extracted with ether in the soxhlet extractor to examine the relationship between extraction time and recovery. All reagents used were of analytical grade. Volatile organic acids (acetic, propionic, butyric and n-valeric acids) and non-volatile organic acids (lactic, oxalic, malonic, fumalic, succinic, maleic, glutaric, α-ketoglutaric, malic and citric acids), 10 mg each, were dissolved in 50 ml of 3N sulfuric acid and then extracted with 100 ml of ether on a water bath at 55°C. The extract was dried over anhydrous sodium sulfate and concentrated to 20 ml on a water bath at (4045)°C. A half of the extract was concentrated almost to dryness on a water bath at (4045) °C and esterified for the analysis of non-volatile organic acids. The other half was employed for the analysis of volatile organic acids without esterification. The recovery of volatile organic acids reached the maximum after 3 hours of extraction and then decreased with increasing extraction time. This fact suggests that volatile organic acids were considerably evaporated during the extraction. It was also found that evaporation to (23) ml of the extract gave higher recovery than evaporation to complete dryness. Non-volatile organic acids, except for malic and citric acids, were almost completely extracted by the 6 hour extraction.

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