The reaction of hydrogen sulfide with sulfur dioxide in aqueous solution yields Wackenroder′s solution, which contains polythionates (S_xO₆^2-: x=3, 4 and 5) and thiosulfate. Various reactions of polythionates with such reagents as sulfite, cyanide, sulfide, permanganate and others are reviewed, in which the thiosulfate and/or thiocyanate formed by these reactions of polythionates are measured titrimetrically, spectrophotometrically and coulometrically. As a result, simultaneous equations can be obtained through corresponding different procedures and can be used for the determination of polythionates in their mixtures with other sulfur anions. Furthermore, modern liquid chromatography is described for the separation of polythionates and thiosulfate, in which quite different chromatographic techniques and conditions were employed.

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A theory on flow rate optimization in column chromatography is presented on the basis of information theory. The quality of a given chromatogram is evaluated by the information flow v which is defined as the time-averaged amount of Shannon mutual information called FUMI. The theory developed here is a universal one: the new formula of FUMI, put-forward here, takes a general form applicable to system evaluation, design and optimization of any chromatographic variables which can be related to Gaussian peak shape.

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Nuclear magnetic resonance relaxation times of carbons including quaternary ones have been measured for strychnine in CDCl₃ at 11.74T. A computer-assisted method of analysis has been applied to interpret the data based on the three models of molecular reorientational motion. The contribution of dipole-dipole relaxation is estimated for the quaternary carbons in the method of analysis without invoking a separate time-consuming measurement of nuclear Overhauser effect factors; this enables us to discuss the mechanism of relaxation in these carbons. The dipolar part is dominant for the quaternary sp³ carbon, whereas contributions other than the Bipolar part are also significant for the quaternary sp² carbons.

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The ultraviolet (UV) absorption spectra of styrene-alkyl methacrylate and -alkyl acrylate copolymers in chloroform solution altered with changing the styrene content. The molar absorption coefficients at 256.2 and 259.2nm were constant over the entire range of composition, while those at 262.8 and 269.6nm decreased with decreasing the styrene content. Hypochromic effects at the latter two wavelengths were observed. Wavelengths of 256.2nm and 259.2nm can be used as the key bands for the determination of the copolymer composition by UV. The bathochromic shift for the UV spectra of the styrene-alkyl methacrylate copolymers and the hypsochromic shift for those of the styrene-alkyl acrylate copolymers were observed. The hypochromic effect was independent of the types of comonomers; the ester group of the comonomer did not have any influence on UV absorption for the phenyl group. However, a methyl group attached to an α-carbon atom of the methacrylate monomer shifted the peak maxima toward lower absorption energies and a hydrogen atom on an α-carbon atom of the acrylate monomer toward higher absorption energies.

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A fluorescent enzyme immunoassay for free thyroxin using glucose oxidase as the label enzyme has been developed. Double antibody solid phase method was used. After separation of bound and free fractions the glucose oxidase activity was measured using a coupled enzyme procedure: glucose and horseradish peroxidase were used as the substrate and coupled enzyme, respectively. Hydrogen peroxide generated from glucose was determined by the fluorophotometric method using p-hydroxyphenylpropionic acid as a substrate. The proposed fluorescent enzyme immunoassay is uninfluenced by thyroxin-binding globulin or by albumin. Free thyroxin values in serum determined by the proposed method correlated well with those obtained by the equilibrium dialysis method (serum: r=0.93). Free thyroxin in a dried blood filter paper disc (3mm in diameter) could be assayed by this method. The mean variabilities(RSD) of within and between assays were 9.6% and 6.9% for sera and 7.6% and 9.1% for dried blood samples, respectively. The measurable range of free thyroxin was from 0.05 to 5ng/dl.

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A new practical method for the rapid microdetermination of hydroxyproline (Hyp) in biomedical samples, such as tissue and urine, in the presence of a definite amount of cysteine as antioxidant was established by means of the modified KISO method using flow injection analysis. This method uses no organic solvent and requires only 9min for each sample, which can be injected every 3min (about 5h is sufficient for 100 samples). A good linear relationship (r=0.99996) was obtained between the concentration of Hyp (0-80μg/ml) and the absorbance (0-0.514). In biomedical samples (hydrolyzates of rat stomach tissue), the recoveries (94.8-103.7%) and the reproducibility (the mean of RSD; 0.484% for ten kinds of rat tissues) were satisfactory. The correlation between values from this method and from the conventional KISO method was shown to be good enough (r=0.966) for hydrolyzate samples (n=95), when a proper amount of cysteine solution was added to both the sample and standard solutions and the concentration of the oxidant was optimized to Hyp contents.

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β-Diketones react with boron trifluoride (BF₃) under mild reaction conditions to give their difluoroborane (BF₂) chelates quantitatively. The complexes gave sharp peaks on both normal- and reversed-phase high performance liquid chromatography (HPLC), while the unreacted β-diketones gave broad peak and poor reproducibility probably due to keto-enol interconversion during the separation. Fe(III) chelate of acetylacetone (Haa) was also found to react with BF₃ to give the BF₂ chelates quantitatively.

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The use of 2-(phthalimino)ethyl trifluoromethanesulfonate in the preparation of carboxylic acid 2-(phthalimino)ethyl ester derivatives for specrophotometric detection in high performance liquid chromatography is described. The reagent is prepared in 60% yield by the reaction of N-hydroxyethylphthalimide with trifluoromethanesulfonic anhydride in the presence of pyridine in dichloromethane and is stable at least for 1 year in a refrigerator. Reactions of carboxylate potassium salts (10_-5M) with a 10-fold equivalent excess amount of the reagent in acetonitrile at room temperature proceed to completion within 10min in the presence of 18-crown-6 as a catalyst. The derivatization procedure with this reagent has been successfully applied to the determination of some carboxylic acids in mouse brain.

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A high performance liquid chromatographic (HPLC) method was developed for the simultaneous determination of Cromakalim, a novel antihypertensive agent, and its major metabolites in human urine. The urine sample was first applied onto a disposable cartridge column of octadecyl silica gel (ODS) for solid phase extraction. The charged sample was then washed with an alkaline solution prior to its elution with aqueous methanol. The eluate was introduced into an HPLC system equipped with an ODS column and was analyzed by a gradient elution technique. In combination with fluorescence detection, this analytical method realized a sensitive determination of Cromakalim and its three major metabolites, simultaneously, in human urine. Urine samples from preclinical trials (Phase I study) conducted on healthy Japanese volunteers were successfully assayed using this new method.

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Small amounts of chloride ion have been determined spectrophotometrically by means of iron(III) alum (NH₄Fe(SO₄)₂• 12H₂O) reagent solution in nitric acid and thiocyanate reagent solution in methanol. Previously developed methods using iron(III) alum and thiocyanate for determining chloride ion are not sensitive enough and/or have non-linear calibration curves. Therefore, attempts to improve these methods were made in the present work. The results are as follows. Higher linearity and better sensitivity of calibration curves were obtained with higher concentrations of iron(III) alum (150-300g/dm³ in 6M HNO₃, 2ml) and mercury thiocyanate reagents (9g/dm³ in MeOH, 2ml, or 4g/dm³ in MeOH, 4ml) in the chloride ion concentration of up to 20mg/dm³. The influence of light on absorbance of the solution was very small, although the temperature dependence on absorbance was relatively great. Effects of nitric acid concentration and stirring conditions were also studied.

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A new sensitive and rapid method is proposed for the spectrophotometric determination of molybdenum in some cobalt and nickel base alloys and steels. The procedure is based on the formation of a molybdenum(VI)-quinalizarin complex in an aqueous micellar solution of cetylpyridinium chloride (CPC) at pH 3.2-4.2. Beer′s law is obeyed over the range 0.05-0.60ppm of molybdenum. The apparent molar absorptivity of the complex is (1.27±0.01)×10⁵l mol^-1 cm^-1 at 580nm and the sensitivity index is 0.0007μgcm^-2 of molybdenum. The experimental factors which affect the color reaction were investigated throughly. The method is free of interference from most of the common metal ions.

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Laser-induced photoacoustic spectroscopy was applied in order to determine trace amounts of iron adsorbed onto the surface of a solid resin Amberlite XAD-2 microparticle of 300μm in diameter as an oxine (8-quinolinol) complex. The photoacoustic measurements were carried out with a single particle in order to avoid any scattering effects. The signal magnitude depended on the iron concentration, which ranged from 5×10^-3 to 3mg for one gram of resin. This dependence deviated from linearity as the concentration became larger than 40μg per gram of resin. The nonlinear behavior was regarded as being a saturation phenomenon resulting from the spatial variation of the optical thickness due to the sample′s spherical form. The saturation effect could be eliminated by focusing the incident beam to a size sufficiently small with respect to the particle diameter.

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A novel nondestructive evaluation method for the adsorption layer thickness of a single microparticle using the frequency characteristics of the photoacoustic signal magnitude and phase is proposed. The adsorption thickness of metal 8-quinolinol chelates on an Amberlite XAD-2 microparticle of about 300μm in diameter was estimated by the proposed method. Measurements were performed with a single particle, and adsorption thicknesses of 10⁰-10¹μm could be examined. A good agreement between the photoacoustic and microscopic determinations was obtained when the thermal diffusion length was longer than the adsorption thickness. The application range with respect to the relation between the thermal diffusion length and the adsorption thickness is discussed qualitatively on the basis of the experimental results of the frequency characteristics of the signal magnitude.

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This method is based on the direct heating of activated carbon (AC) adsorbed bismuth-potassiumo-ethyldithio-carbamate [potassium xanthogenate (KetX)] complex: that is, AC is introduced directly as "AC-suspension" into a carbon tube atomizer, without the desorption of bismuth from the AC. To a sample solution (pH 6.5-8.0) containing less than 0.10μg of bismuth, potassium tartrate as a masking agent, 120mg of KetX and 50mg of AC are added, and the mixture is stirred for 20s. After separation of AC from the aqueous phase through a membrane filter, 5.0ml of AC-suspension are prepared by adding water to the AC. Then, aliquots (10μl) of AC-suspension are injected into the atomizer, and the bismuth peak-height is measured under optimal instrumental operating conditions. The determination limit was 0.005μg/100ml (S/N=3), and the relative standard deviation was 2.0% (n=8). This method was applied to the determination of bismuth in river-bottom and submarine sediments.

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Trace amounts of tellurium in urine were determined by atomic absorption spectrometry using a graphite furnace atomizer. The urine was concentrated and digested with HNO₃-HClO₄. The bulk of salts and interfering elements were removed by 4-methyl-2-pentanone extraction procedure, and finally the organic phase was analyzed on a graphite furnace atomic absorption spectrometer equipped with an auto sampler having a concentration function; Recoveries of tellurium added to urine sample range from 90 to 103%; relative standard deviation was 9% at the 0.1μg level. Tellurium contents in urine ranged from <0.1 to 1.2μg/l.

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The atomization behavior of Fe, Co and Ni on electrothermally heated metal-strip atomizers was studied. Argon or hydrogen was used as a purge gas. The heating metals (W, Mo and Ta) showed different effects regarding atomic absorption peak profiles. The Ta strip surface was covered with Ta oxide, which did not decompose at temperatures below 2000°C. As a result, tailing of signal peaks was caused. Under a hydrogen atmosphere, the signal peaks were mostly sharpened due to reductive reactions between the analyte and hydrogen, but exceptionally broadened for Co and Ni with a W-strip atomizer. It was postulated that a solid solution was formed between the analyte atoms and the metal surface.

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A flow injection system is described for the determination of inorganic and total mercury (inorganic mercury and organomercury) by the cold vapor atomic fluorescence method. In the determination of inorganic mercury, a sample

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This report describes the determination of technetium in solutions from spent fuel reprocessing processes. Inductively coupled plasma emission spectrometry (ICPES) was employed after alkaline precipitation and/or anion exchange. Technetium in the form of pertechnetate is roughly separated from other elements by merely changing the acidity of the sample solution to make it alkaline. This works because most of the fission products (FPs) are precipitated along
with the heavy metals in an alkaline medium, whereas technetium is not. Technetium in some solutions from highly active processes is further purified with the aid of basic or weakly acid anion exchange after the alkaline precipitation mentioned above. The decontamination factors were found to be more than 10⁴ and 10⁵ for FPs and for the heavy metals, respectively. The amount of technetium separated is determined by ICPES, which measures the Tc II 261.00nm line without any significant interference. The relative standard deviations are 2.2% at 9μg ml^-1 and 4.9% at 0.9μg ml^-1 of technetium. The proposed method has been applied to samples from various streams of the Tokai Reprocessing Plant; the highly active liquid waste, the spent fuel dissolver solution, the aqueous phase of solvent extraction and the plutonium product solution.

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The analytical potentiality of the combined use of high-energy photon activation and low-energy photon detection has been investigated by irradiating 36 elements with 30-MeV bremsstrahlung. The characteristic X-rays and low-energy gamma-rays from the activation products were measured with an intrinsic high-purity germanium detector, and the experimental sensitivities have been estimated. A comparison was applied to the results with the conventional gamma-ray measurements with a lithium-drifted germanium detector. The attenuation of the low-energy photons due to a sample matrix was also considered. Practical detection limits for several elements were evaluated by analyzing a biological standard reference material, NIST Orchard Leaves. For Ba, Br, I, Ni, Mo, Pb, Sb and Zn, detection limits were lowered by low low-energy photon spectroscopy. From the results, applicability and versatility of this method have been demonstrated.

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When less than 100mg of powdered carbonate mineral sample was stirred with an aqueous suspension of H⁺type resin (2cm³ resin in 5cm³suspension), F^-in the sample was quantitatively extracted into the aqueous phase. The ion chromatographic analysis of the aqueous phase enabled us to determine F^- in the sample at the μg g^-1 levels with precision of 5% relative standard deviation. The lower limit of determination was 0.2μg g^-1 when 100mg of sample was used. This method was applied to F^-determination in the Geochemical Standards Limestone (JLs-1) and Dolomite (JDo-1) issued from the Geological Survey of Japan.

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The oxidation of manganese(II) in a benzoylacetonate and a dibenzoylmethanate complex in water-saturated organic solvents by dissolved atmospheric oxygen was measured. The rate of oxidation in carbon tetrachloride and toluene was higher: dibenzoylmethane>acetylacetone>benzoylacetone. When the ligand was the same, it was higher in toluene than in carbon tetrachloride, but was very low in 4-methyl-2-pentanone. Such an oxidation also occurred in the organic phase of solvent extraction systems with these β-diketones. For this reason the extraction was enhanced very much when the two phases were agitated for a long time.

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The concept of thin-layer chromatography (TLC) "chemical diskette" is demonstrated whereby high performance liquid chromatographic (HPLC) effluents are delivered and stored along a linear path on a TLC surface. The time coordinate normally associated with the HPLC chromatogram is transformed therefore to a spatial coordinate on the solid matrices. After the HPLC analytes have been deposited on the TLC in a pre-determined pattern as controlled by a computer, the pattern can be retraced and interrogated by various spectroscopic methods. In the present demonstration, the analytes are detected by fluorescence where an optical fiber carries the laser beam for excitation. The LC/TLC diskette method was experimentally implemented by replacing the pen of a high resolution digital x-y recorder with the outlet tube of a microbore HPLC column. The writing rate and pattern of the LC effluent on the TLC plate were controlled by the x-y recorder as driven by a microcomputer. After removal of the LC solvent, the adsorbed analytes on the TLC surface were interrogated by retracing the pattern with the He-Cd laser irradiation as carried by the optical fiber on the pen holder. Other fibers on the same holder collect and transmit the fluorescent emission to the detection system. The detection limits were in the low femtomole range for two amino acids derivatized by naphthalenedialdehyde. Also, it was possible to detect di-derivatized lysine, which was not quenched as in the solution phase, on the TLC surface.

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