The composition of the thiocyanato-N-hydroxyethylethylenediamine-N, N', N'-triacetato complexes of nickel (II), copper(II), and cobalt(II) was M(edtaOH)-(NCS)^2-. The stability constants of these complexes are 5.6, 2.1, and 1.6 for nickel(II), copper(II), and cobalt(II), respectively, at 25°C in 1.0 M NaClO₄. Thiocyanate ion may coordinate to metal through nitrogen atom. The molar extinction coefficients of Ni(edtaOH)-(NCS)^2- and Co(edtaOH)(NCS)^2- in the visible range are larger than those of Ni(edtaOH) (H₂O)^-and Co-(edtaOH) (H₂O)^-, respectively. However, the molar extinction coefficient of Cu(edtaOH)(NCS)^2- is smaller than that of Cu(edtaOH) (H₂O^)- at shorter wavelengths than 828 nm.

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A flow coulometric column electrode was developed for the separation of metal ions by using multi potential sweep method. This method was successfully applied to the separation and determination of lead and copper in cadmium metal. Glassy carbon grains of 60 to 100 mesh (Tokai Denkyoku, GC-20) were packed in the working electrode chamber (180 mm×7 mm, thickness 5.5 mm) by the balance-slurry packing method. A glassy carbon plate (Tokai Denkyoku, SC) was used as an electric lead to the working electrode to maintain a uniform potential during the potential sweep. The counter electrode was a silver-silver chloride electrode and the reference electrode was a saturated calomel electrode.
The working electrode was separated from the counter electrode with a cation exchange membrane (Asahi Garasu, Selemion CMV). Copper and lead ions were separated by the column electrode in 1 M phosphoric acid. The two metal ions had different retention times on the electrode and were eluted separately from the column. The eluting metal ions were electrolyzed with the another flow coulometric column electrode of almost the same structure at constant potential and a chromatogram was obtained. Peak resolution values for copper and lead were 1.5 to 2 under these conditions; flow rates of 0.5 to 1.0 ml/min and sweep rates of 5 to 20 V/min in the potential range between +0.5 and -1.0 V(SCE). Lower limits of detection were 0.5×10^-8 mole for Pb(II) and 1×10^-8 mole for Cu(II).

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Hydrophobic gel particles containing dithizone were prepared by swelling polystyrene beads (2% divinylbenzene) with a dithizone-monochlorobenzene solution. The selective extraction, separation and enrichment of trace mercuric ion in aqueous samples with the dithizone gel beads column were investigated. A solution containing a known amount of mercuric ion, adjusted to pH 1 with sulfuric or nitric acid, was passed through the gel column. Mercury trapped as an orange primary dithizonate, Hg(HDz)₂, can be back-extracted quantitatively with 8 N hydrochloric acid. Mercury was trapped selectively at pH 1 from the sample solution in the presence of various metal ions such as zinc, cadmium, iron(II) and lead. Under these conditions the copper(II) ion was also trapped as a copper dithizonate in the gel column, but could be masked with EDTA. With the combined use of EDTA as a masking agent, mercury in synthetic sea water and natural sea water at ppm or ppb level, was seccessfully separated and enriched by this procedure.

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A method for the identification and the determination of chlorinated methane, ethane derivatives added in petroleum by NMR spectroscopy was investigated, and the application of this method to the analysis of imported petroleum products used as paint remover or cleaning compound was also examined. The NMR measurements were made with a Hitachi R-20 spectrometer (60 MHz). The probe temperature during measurements was 34°C. In the NMR spectra of C₁, C₂-chlorinated hydrocarbons dissolved in petroleum such as kerosene, the proton signals appeared at up-field by the magnetic anisotropy effect in the case that aromatic constituents existed. These shifts were related to their amounts in the petroleum. The identification of chlorinated hydrocarbons was possible by graphic representation of the shifts for each proton signal, which could be used for the survey of the chemical shifts of chlorinated hydrocarbons in petroleum solvent. The integral intensity or peak height of the characteristic peak (CH, CH₂, CH₃) was used directly for the determination of C₁, C₂-chlorinated hydrocarbons. The standard mixtures of 1, 1, 1-trichloroethane-kerosene and 1, 1, 1, 2-tetrachloroethane-kerosene were examined under following conditions: range of concentration; (550)% (1.0g of the mixture and 0.2g of methyl benzoate or benzyl chloride as internal standard in 2 ml CCl₄), RF; 4×10³μV, sweep width; 2.4 Hz/s. The standard deviations of 1, 1, 1-trichloroethane and 1, 1, 1, 2-tetrachloroethane were 0.60% respectively. This method is simple, rapid and does not require the calibration curve.

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The procedure for the determination of amino acids and related compounds in biological fluids was improved and simplified by double-chromatogram method (DC-method). This method requires 2 sets of buffer and ninhydrin pumps, flow cells and photomultiplier systems but only one recorder. Using Aminex A-5 resin, acid and neutral amino acids were chromatographed by a long column (100×0.25 cm) and basic amino acids by a short column (50×0.25 cm) at buffer flow rate of 5.5 ml/h according to the Spackman's buffer system, respectively. However, different from the Spackman's method, these two chromatographic procedures were started at the same time. Signals from two photomultiplier systems were recorded in turn in every 3 seconds on a same recording paper. After 245 min, the temperature of the both columns was raised from 30°C to 50°C at the same time. There-fore, only one heating bath was used. It took 8 h to analyze acid and neutral amino acids and 9 h to analyze basic ones. Consequently, by the DC-method, amino acids and related compounds in biological fluids could be estimated within 9 h. The reproducibility was (100±2.1)% in a range 0.0052 to 0.100μmoles of amino acids. This DC-method could be run on a Shibata AA-600 amino acid analyzer without any modifications of the apparatus. More rapid and simplified procedure for the measurement of amino acids and related compounds in biological fluids could result from this DC-method.

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Selenium(IV) and tellurium(IV) are quantitatively reduced and precipitated as metallic form in the N, N-dimethylformamide solution containing hydrochloric acid after heating on a water bath. Twenty to two hundred mg of selenium and tellurium can be determined gravimetrically by use of the reagents. Tartaric acid was used together with N, N-dimethylformamide to precipitate only selenium from mixtures of Se(IV) and Te(IV).
The recommended procedure is as follows: Take an aliquot of the sample solution containing Se(IV) (≤150 mg) and Te(IV)(≤100 mg) in a 100 ml beaker. Evaporate the solution up to dryness on a water bath after addition of nitric acid. Add 20 ml of hydrochloric acid and 50 ml of N, N-dimethylformamide, transfer the solution into a stoppered 200 ml Erlenmeyer-flask, and keep to stand for 4.5 hours in boiling water to complete the precipitation. Filter the precipitated selenium and tellurium on a sintered glass filter, and weigh the precipitate after washing and drying (weight A).
Then take the same volume of the sample solution in another beaker, treat as above, and then add(33.5)ml of hydrochloric acid (2+1) and 20 ml of N, N-dimethylformamide. Transfer the solution to a stoppered 100 ml Erlenmeyer-flask containing 2 g of tartaric acid, and heat for 3 hours in boiling water. Filter the precipitated selenium, and weigh selenium (weight B). The weight of tellurium is obtained as A-B. The effect of ten-odd cations and some anions on the determination was also examined.

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Biphenyl formed from dechlorination of polychlorinated biphenyl (PCB) was measured by gas chromatography with flame ionization detector (FID). PCB in samples was extracted with less than 5 ml of n-hexane, and the extract was transferred to a flask (volume 50 ml) with a ground-glass joint and was adjusted to 5.0 ml with n-hexane. To the solution, 1 ml of Vitride reagent {70% NaAlH₂(OCH₃CH₂OCH₃)₂ in toluene} was added. The mixture was refluxed for 1 hour at 100°C, and cooled to room temperature. The reaction mixture was then hydrolyzed by adding 10 ml of water under cooling, followed by addition of 1.5 ml of 6 N hydrochloric acid under vigorously shaking to neutralyze the solution.
The formed biphenyl in hexane layer was measured by FID gas chromatography (Column 5% SE-30 3 m×4 mm id., Column temp. 145°C). As chlorinated benzenes, BHC, aldrin and biphenyl interfered the determination of PCB, silica gel column chromatography was performed before dechlorination to remove such interferences. The hexane extract was applied on a silica gel column (2.5 g of Wakogel S-1 activated at 130°C for 15 hrs.), and elution was carried out with 130 ml of n-hexane. Chlorinated benzenes were eluted in the first fraction (030) ml, and PCB and DDE in the next fraction (30130) ml. DDE, however, had no interference for dechlorination and determination of PCB. Aldrin, BHC and biphenyl were retained in the column under the elution condition.

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The determination of uranium and plutonium in mixed oxide fuels has been developed by sequential potentiometric titration. A weighed sample of uranium and plutonium oxides is dissolved in a mixture of nitric and hydrofluoric acids and the solution is fumed with sulfuric acid. After the reduction of uranium and plutonium to uranium(IV) and plutonium(III) by chromium(II) sulfate, 5 ml of buffer solution (KClHCl, pH 1.0) is added to the solution. Then the solution is diluted to 30 ml with water and the pH of the solution is adjusted to 1.01.5 with 1 M sodium hydroxide. The solution is stirred until the oxidation of the excess of chromium(II) by air is completed. After the removal of dissolved oxygen by bubbling nitrogen through the solution for 10 minutes, uranium (IV) is titrated with 0.1 N cerium(IV) sulfate. Then, plutonium is titrated by 0.02 N cerium(IV) sulfate. When a mixture of uranium and plutonium is titrated with 0.1 N potassium dichromate potentiometrically, the potential change at the end point of plutonium is very small and the end point of uranium is also unclear when 0.1 N potassium permanganate is used as a titrant. In the present method, nitrate, fluoride and copper(II) interfere with the determination of plutonium and uranium. Iron interferes quantitatively with the determination of plutonium but not of uranium. Results obtained in applying the proposed method to 50 mg of mixtures of plutonium and uranium {(7.550)}% Pu were accurate to within 0.15 mg of each element.

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The suitability of m-aminophenols as a catalytic indicator for the determination of manganese(II) with EDTA was evaluated. Manganese(II) catalyzes the oxidation of aromatic amine and phenol derivatives by hydrogen peroxide in hydrogen-carbonate ion solutions. The effect of substituent groups on the catalytic oxidation of the indicator was investigated. and the criteria for the selection of the indication reaction were briefly discussed. The optimum catalytic action of manganese(II) ion was limited in carbonate concentrations of (0.30.4) M and pH ranges between 8.4 and 9.7. In N, N-dialkyl-m-aminophenol indicator system, the absorption maximum of the oxidation products shifts to longer wavelength and bathochromic effect of substituent group was observed. The recommended procedure for manganese determination is; add 3 ml of 0.2% m-aminophenol(I) {or N, N-diethyl-m-aminophenol (II)} and 1 ml of 3% hydrogen peroxide to about 50 ml portion of 0.4 M carbonate solution containing known amounts of EDTA. Titrate the solution with a manganese(II) solution. At the end point, the solution turns deep orange(I) or violet(II) by the catalytic action of manganese(II). This catalytic titration method was applied to the determination of 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 standard titrimetric method with metal indicators. The coefficient of variation for the catalytic titration of manganese was 0.1 %.

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A simple and rapid ultraviolet spectrophotometry was proposed for the determination of microamounts of chromium(VI) with ammonium 1-pyrrolidinecarbodithioate (APDC) as a complexant. The recomended procedure is as follows: To a sample solution containing up to 35 μg of chromium(VI), 3 ml of 12 M hydrochloric acid solution and 1 ml of the 0.5% APDC solution were added and the resulted solution was diluted with water to about 20 ml. The solution was heated for 2 minutes in a boiling water bath. After cooling the solution to room temperature under flowing tap water, the solution was transfered to a 25 ml volumetric flask and diluted to the mark with water. The absorbance of the complex was measured at 265 nm against the reagent blank. The absorption spectrum of the chromium-PDC complex exhibited the maxima at 225 and 265 nm, the latter of which was chosen for a measuring wavelength because of the low absorbance for the reagent blank and of the good reproducibility. The absorbance of the complex in 1.4 M HCl solution remained constant for 6 hours. Beer's law was held up to 35 μg/25 ml for Cr(VI) at 265 nm. The molar absorptivity was 3.17×10⁴, and the coefficient of variation was 0.6% {5 determinations at the 15μg Cr (VI)/25ml}. The determination of 20 μg of Cr(VI) was not interfered in the presence of twenty-five fold amounts of Na, Mg(II), Al(III), K, Ca(II), Cr(III), Mn(II), or Zn(II), but was interfered by 2.5 fold amounts of Mo(VI) or Ni(II), 5 fold amounts of Ag or V(V), 25 fold amounts of Cu(II), Fe(III, II), Co(II), Hg(II), Pb(II), or Sn(IV).

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This selective detection is based on the selective removal of alkyl nitrites, alkyl nitrates, and nitroparaffins from the compounds containing halogen or nitrogen which are detected with an electron capture detector. The components eluted from a GC column are introduced into the reaction column (120×5 mm i.d.) packed with powdered lithium aluminum hydride, and then detected with an ECD. After passage through the reactor, reactive species such as alkyl nitrites, alkyl nitrates and nitroparaffins were subtracted from the effluent gas stream by the formation of non-volatile derivatives and could be identified by their absence in the chromatograms. Furthermore, type analysis of the halogen compounds detected with an ECD is carried out by use of a Molecular Sieve 5A column (120×5 mm i.d.) as a postcolumn subtractor. It has become apparent that n-alkyl halide and straight-chain dihaloalkanes were subtracted with the MS 5A column while branched-chain mono- and dialkyl halides, gem- and vic-dihalides, and polyhalomethane were not subtracted. These techniques were used to identify components in auto exhaust gas sample concentrated on usual GC column packing and five halogen compounds were identified. These include carbon. tetrachloride, chloroform, trichloroethylene, tetrachloroethylene, and 1, 2-dibromoethane.

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The chromatographic behavior of saturated aliphatic di- and tricarboxylic acids of C₂C₈ on the column of strongly basic anion-exchange resin was studied. A 1.1 cmφ×10 cm column of Dowex 1-X8 chloride {(200400)mesh} was used. Acids in the eluate were detected photometrically by means of indicator color developement. The condition of elution was as follows. [Cl^-]: 0.2 M, pH 2.0, 4.5, 5.0, 5.5, and 12. Temp.: 30°C. Flow rate: 60 ml/h.
The distribution ratio, D_v, of divalent acid is represented by the equation,
D_v=α₀χ₀+α₁χ₁/[Cl^-]+α₂χ₂/[Cl^-]²
where α₀, α₁, and α₂ are molar fractions of undissociated molecules, monovalent and divalent ions (here α₀+α₁+α₂=1) respectively, and then χ₀, χ₁, and χ₂ are characteristic coefficients of them, respectively.
The D_v values were given by the elution experiments, then the χ values were calculated according to the above equation.
The behavior of these acids did not essentially differ from that of the fatty acids. However, the abnormality which had been observed in formic acid, spread over from oxalic to glutaric acid in the case of dicarboxylic acid homologs. Especially, the χ₂ values of the acids from malonic to adipic acid were practically equal each other, besides, malic and tartaric acid also gave almost equal values, so that the high pH media were not adequate to separation of such acids.
The χ₁ values of malonic and methylmalonic acid were extremely higher than those of oxalic and succinic acid. The phenomenon was observed in maleic and citraconic acid in the case of unsaturated acids. This is interesting in relation to the structure of such monovalent ions in aqueous solution.

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Prior to analysis of blood gases, CO₂ and O₂, a simulation experiment was carried out with standard samples known in their concentrations to testify reliability of an equation expressed as C=R.E./P.R.+C.T. (C:concentration, R.E.:regression equation between concentration and peak area, P.R.: permeation rate, C.T.: correction term). The relative errors in the measurements to the standard samples were 5.17% for O₂ and 8.34% for CO₂. The errors were reduced to 2% for both gases within a normal range of their concentrations in blood. This result proved satisfactory analysis of blood gases with the present method.
Determinations of total O₂ and CO₂ in blood were then performed with 100 microliter of heparinized blood. Lactic acid was used as a gas generating material for the determination of total CO₂ and a mixture of K₃Fe(CN)₆ and saponin(1+1) for total O₂. The coefficients of variation were 2.75% and 1.98% for the total O₂ and CO₂, respectively. The good reproducibility assured an application of the present method to blood sample. Samples were analyzed in about 15 minutes, that is, approximately 10 minutes shorter than with commonly used Astrup's apparatus. The correlation between both methods, PT-GC and Astrup's, was very good (r_O2=0.932, r_CO2=0.973).

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Organic peroxides are widely used in industry and known to be evolved in autoxidation and combustion reactions. The peroxides have been generally determined by iodometric method, although the method could not exclude analytical errors caused by incomplete reaction and formation of iodine by dissolved oxygen. The present study has been undertaken to measure dialkylperoxide, hydroperoxide, peroxyester and diacylperoxide by gas chromatography. These heat-labile peroxides were unable to be analyzed at a high temperature, while satisfiable chromatogram was not obtained at a low temperature because of their low vapor pressure. Therefore, this method required a strictly established temperature. Column packings of PEG 6000, DNP and Silicone SE-30 and the flow rate of carrier gas in (10100) ml/min had no effect on decomposition of the peroxides. Analysis conditions for typical peroxides were summarized as follows; t-butyl cumyl peroxide: PEG 6000, 100°C (column temp.), 20 ml/min (flow rate), 2-phenyl-2-propanol (internal standard), t-butyl hydroperoxide: Silicone-SE-30, 80°C, 10ml/min, t-butanol, t-butyl peroxy benzoate: Silicone SE-30, 100°C, 100 ml/min, acenaphthene. Their percentage errors of determination were in the range of 0.11 to 0.85%. Some organic peroxides which decomposed immediately after vaporization, e.g. benzoyl peroxide, could not be determined by this method.

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A 1:2 complex formed by the reaction between gallium and Chromazurol S (CAS; H₄L) was examined in above pH 3 by the spectrophotometric method. The formation reaction of the 1:2 complex from the 1:1 complex with hydrolysis of the gallium ion may be expressed by the following equation.
GaHL+H₂L^2-+H₂O=Ga(OH)(HL)₂^4-+2H⁺
The equilibrium for the 1:3 complex formation reaction may be expressed by the following equation.
Ga(OH)(HL)₂^4-+H₂L^2-=Ga(HL)₃^6-+H₂O
The formation constants of the 1:2 and 1:3 complexes are obtained as (6.0±0.2)×10^-3 and 1.65×10⁴ at pH 4.4, respectively and the first hydrolysis constant of the gallium ion is calculated to be (5.2±0.2)×10^-4 from the relation between the formation constant of the 1:1 complex and pH, at the ionic strength 0.1 and 25°C. A complex with an absorption maximum at 580 nm formed in below pH 3 will be Ga(HL)₂^3-.

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The UHF-plasma torch emission spectrometry by use of introduction of generated metal hydride was studied on several metal species. Defined aliquots of sample solution acidified to (1.04.5) M with hydrochloric acid were injected in a generator bottle containing 20 ml of (26)% sodium borohydride solution as a reductant and then hydride was introduced to the torch by argon carrier gas.
The detection limits in μg were; arsenous 0.01 (228.8 nm), arsenic 0.05 (228.8 mn), antimony(III) 0.025 (259.8 nm), bismuth(III) 1 (298.8 nm), germanium(IV) 0.05 (303.9 nm), lead 10 (405.8 nm), selenium(IV) 2 (204.0 nm), tellurium(IV) 2 (214.3 nm), and tin (II, IV) 0.1 (270.7 nm). The calibration curves were linear and passed through the origin in the range of arsenous {(0.018)μg}, antimony {(0.0250.7)μg}, bismuth {(1.015)μg}, germanium {(0.21.5)μg}, and tin(II, IV) {(0.13)μg} when 2% sodium borohydride was used, and arsenic {(0.17)μg} when 6% sodium borohydride was used.
In applications to analysis of steels for arsenic and tin and of molybdenum for tin without prior separation, 6% sodium borohydride was used. The analytical data for steels were satisfactorily accorded with the referred values.

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