A new automated analysis sytem for the identification of a variety of polymers has been developed by using pyrolysis gas chromatography in conjunction with on-line data processing with a personal computer. A polymer sample was pyrolyzed at 670°C with a Curie point type pyrolyzer. The volatile pyrolyzates were separated on a fused silica capillary column (DB17) and monitored with a nitrogen phosphate detector (NPD) as well as a flame ionization detector (FID). The use of NPD gave the increased reliability of the identification of nitrogen-containing polymers such as amino-modified silicones and quaternary ammonium salt type polymers because of its high selectivity for nitrogen-containing compounds. The pyrograms obtained were normalized by the use of retention indices, in which olefin peaks produced by the pyrolysis of polyethylene were used as the reference for the calculation of the retention indices, and then searched against a home-built data-base. Similar indices were introduced to make it easy to evaluate the similarities between sample pyrograms and standard ones in the data-base. A series of processes involved in the proposed method were fully automated.

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Attenuated total reflection (ATR) IR microscopy has been investigated for the local analysis of the surface of materials, such as polymer and polymer composite. The unique ATR prism, made from zinc selenide, was designed to achieve ATR measurement in the transmission path of the conventional infrared microscope. The prism is pillar shaped-having hexagonal cross section with one corner recessed inward. The prism comprises four totally reflecting surfaces including a sample-contacted surface on which the infrared beam is focused. The reflecting surfaces are so oriented that the optical axis of the incident beam agrees well with that of the outgoing beam even if the measured point of interest is changed on the sample surface. Consequently, this ATR system actualized not only the point analysis but line and area analyses indispensable for the local analysis of the sample surface. The minimum measurement size in the point analysis was about 10 μm square. The precision of absorption intensity and the spatial resolution in the line analysis were 1.0% in the RSD and 20 μm in length, respectively. The effective dimensions for the area analysis were 1.3 mm by 6.6 mm.

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Characterization of diamond films by XPS was carried out by measuring the FWHM (full width at half maximum) and the peak shape of a core C 1s spectrum, and this method was also applied to other carbon films. C 1s peak shapes of natural diamond, graphite carbon, amorphous carbon, glassy carbon, polyethylene (PE) and diamond films formed by the CVD method were analyzed. The C 1s peaks of natural diamond and diamond films showed the same FWHM value, i.e., the diamond films had diamond structure. While the C 1s peak of the natural diamond was symmetric, and those of the other carbon samples were asymmetric. The C 1s peak shape of diamond films was similar to that of amorphous-carbon containing C-H bonds. As a result, it was found that the diamond films contain the C-H bonds in their structure.

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Molybdosilicate blue spectrophotometry after fluoride separation was used to determine trace silicon in high purity graphite samples. The analytical procedure was as follows; decompose 1.0 g of graphite sample with a solution of 0.5 g of sodium metaperiodate in 20 ml of perchloric acid by heating the solution at 200°C in a PTFE tube. After cooling, add hydrofluoric acid and then sulfuric acid to yield silicon tetrafluoride. Transfer the fluoride completely into a boric acid solution by purging it with a nitrogen flow of 1000 ml/min. Then, transfer the solution into a 25 ml flask and add hydrochloric acid and ammonium molybdate to form molybdosilicate. After adding oxalic acid and ascorbic acid, measure the light absorbance of the solution at 810 nm. By this method, sub-ppm level silicon in the graphite standard sample G5 from the Japan Atomic Energy Research Institute (JAERI) was successfully determined. Recovery (n=10) was 101 % for 10 μg of silicon, and the detection limit given by 3σ of blank value was 0.05 ppm for 1 g of graphite. This study was carried out as a part of the research program of the special committee for graphite analysis of JAERI.

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Establishment of the determination procedure for trace impurities in WSi₂ is increasingly required since the disilicide is being used as a source material of LSI. We studied the determination by graphite furnace AAS and ICP-AES, where tungsten was removed by cation exchange separation and silicon was separated by volatilization after it had been transformed to SiF₄. The analytical procedure is as follows; dissolve 1.0 g of the sample in a HF-HNO₃ solution and add 1 ml of HClO₄. Fume the solution to dryness. After cooling, decompose the formed tungstic acid with 20 ml of H₂O₂. Then, pass the solution through an ion exchange column (i.d.: 9 mm, volume: 13 ml) packed with Dowex 50-X4 (100200 mesh). After washing the column with 100 ml of 0.1% H₂O₂, elute the analytes with 90 ml of 2 M HNO₃ and dilute the eluate to 100 ml. Analyze aliquots of the eluate by AAS and ICP-AES. Recoveries of 97% or more were obtained respectively for the analytes of Al, Ca, Cd, Co, Cr, Fe, Ga, K, Mg, Mn, Na, Ni, Pb, Ti and Zn. The analytical concentration range by this procedure was from 0.0n ppm to 0.0n%.

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Flotation-pairing ion exchange-extraction and spectrophotometric determination of trace amounts of phosphate and arsenate were examined. Ion association complexes of heteropoly acids and a bulky cationic dye floated on the interface between an aqueous and a less polor organic solvent phase. After the flotation, the heteropoly acids were exchanged for an anionic dye, which have a high molar absorptivity and the similar maximum absorption wavelength to the cationic dye. The sum of the absorbances of the cationic and the anionic dyes was measured. In this work, malachite green (MG⁺) and 4'-hydroxy-3, 5, 3', 5', 2", 6"-hexachlorofuchsone (Cl₆BZ), a hexachloro derivative of benzaurin, were used as a cationic and an anionic dye. The recommended procedure for phosphate determination is as follows. To a 50-cm³ separatory funnel, take sample solution (up to 10 cm³); if arsenate coexists, add 0.1 cm³ of 2 × 10^-2 M Na₂S₂O₃ to reduce arsenate to arsenite. Then, add 1 cm³ of 10 M hydrochloric acid, 1 cm³ of 0.4 M (as Mo) molybdate, 0.5 cm³ of 5 × 10^-4 M Malachite Green, and 2 cm³ of flotation solvent (Isobutyl methyl ketone + cyclohexane= 1 +8 v/v). After shaking for 5 min, discard the aqueous phase, and wash the organic phase 2 times with 5 cm³ of water. After 1 cm³ of 2 × 10^-4 M anionic dye solution, 8 cm³ of 1, 2-dichloroethane and 5 cm³ of borax buffer (pH 9) are added, shake 10 times by hands. After the phase separation, measure the absorbance of the organic phase at 620 nm. As arsenate reacts under the same conditions as phosphate, arsenate can be determined by subtracting the amounts of phosphate from the total amounts of phosphate and arsenate which were obtained in the absence of Na₂S₂O₃. The apparent molar absorptivity of phosphate or arsenate was 5.7 × 10⁵ dm³ mol ^-1 cm ^-1, and the absorbance of the reagent blank was 0.005. Six times concentration was achieved when 30 cm³ of aqueous phase and 5 cm³ of extraction solvent were used. Bulky anionic ions, such as iodide, perchlorate and lauryl sulfate, did not interfere with the determination of phosphate and arsenate. This method was applied to the determination of phosphate in seawater and iron and steel samples.

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Polarographic reduction wave and hydration of carbonyl groups of 2, 3-diketo-L-gulonic acid (DKG) were studied in various pH solutions by d.c. polarography, cyclic voltammetry and spectrophotometry. Three kinds of polarographic reduction waves A [half wave potential (E_1/2) = -0.67 V vs. SCE], A and B (E_1/2= -1.11 V) and B and C (E_1/2= -1.02 V) obtained in acid, neutral and alkaline solutions, respectively, were observed due to the carbonyl groups of DKG. Same kind of reduction waves were also observed in various pH solutions using cyclic voltammogram, but no corresponding oxidation waves were seen, indicating the reaction to be irreversible. Formation of 3, 4- and 2, 3-endiol forms of 2, 3-diketo-L-gulono-δ-lactone (3, 4- or 2, 3-End.DKGL, respectively) from DKG via isomerization and cyclization was tested spectrophotometrically. In neutral solution, only 3, 4-End.DKGL was observed, while both the 3, 4- and 2, 3-forms were observed in alkaline solution (pH 10.8). Based on these results, the carbonyl groups of DKG are found to have at least three different hydration forms which could be fully hydrated in acidic pH range, mono-hydrated at the C-3 position in neutral pH range, and not hydrated in alkaline pH range. The pathway for the formation of 3, 4- and 2, 3- End.DKGL from DKG was proposed.

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A method for the preparation of calibration graphs has been one of the most important problems in solid sampling technique with atomic absorption spectrometry. In order to dissolve this problem, the standard addition method for solid sampling technique is proposed for the direct determination of nickel, cobalt, copper and manganese at the ppm levels in powdered biological samples by atomic absorption spectrometry. Accurate analytical results have been obtained by using a miniature cup with solid sampling. This method is also applied to those at the sub-ppm levels in some powdered biological samples, which should be concentrated by a pre-ashing method with a conventional electrothermal Muffle furnace. For these pre-ashed powdered samples it was also difficult to prepare the calibration graphs. However it becomes possible to obtain good analytical results when the calibration graphs are prepared by the proposed standard addition method for solid sampling technique.

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By using a CO₂ supercritical fluid (SCF) as FIA carrier and chemiluminescent (CL) reaction medium, a SCF-FIA/CL system was developed in order to determine small amount of lactone. The system was comprised of a single flow line; and a cylinder for CO₂ SCF, high pressure pump, two injectors (Rheodyne 7125 : 100μl for reagents; 20 μl for sample), detector and recorder which were set up on the line, in order. A CL is produced as follows. Lactone reacts with sodium hydroxide and sodium hydroxide/ethanol, and changes to oxycarboxylic acid and glycolic acid ester, respectively. These two compounds react with each other, and the diester is finally produced. The diester reacts with dissolved oxygen, and a hypercompound, such as peroxide of oxalic acid diester is produced. The exited compound being a CL emitter produces the CL and the CL is enhanced in SCF. Analytical characteristics for γ-butyrolactone (γ-BuLac) as a representative were as follows. Lower detection limit: 1.0 ×10^-10 M (20 μl injection method: S/N=2). Lineality of the calibration: 1.0×10^-91.0×10^-7M. Selectivity: excellent to lactone. Reproducibility: 5.5% in terms of relative standard deviation (5 repeated runs for 1×10^-8 M γ-BuLac in 20 μl injection volume). Analytical time required: ca. 3 s. Recovery test for γ-BuLac in coffee essence was successfully achieved.

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Highly selective determination of triphosphonucleotide such as adenosine triphosphate (ATP) was established by a flow injection method with chemiluminescent detection of 1, 10-phenanthroline. The high selectivity is obtained by loading triphosphonuleotide such as ATP chemically to copper(II)-modified clinoptirolite (zeolite). The analyte is indirectly determined by a CL detection of copper(II) eluted from Cu-Zeo through a material exchange between Cu-Zeo and analyte. The system is comprised of three flow lines, and one of them has the material exchange column (4.5 mm i.d., 15 cm long) packed with the Cu-Zeo of 2.4 g (particle size: 0.0740.125 mm ; loading of 2×10 ^-6 mol ATP). The limits of determination by 100 μl injection method were 50 fmol to 2.0 pmol for ATP, 60 fmol to 1.0 pmol for uridine triphosphate, 50 fmol to 3.0 pmol for guanosine triphosphate and 80 fmol to 1.0 pmol for cytidine triphosphate. The relative standard deviation was 2.1 % in 5 repeated runs of 1×10 ^-9 M ATP. The selectivity was high and the CL intensity of 1×10 ^-9 M ATP alone was not interfered by coexistence of 1×10^-4 M other nucleotides and their derivatives. The present method was also successfully applied to determine number of bacteria in normal human urine.

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Interactions between triphenyltin chloride (TPTCl) and several anions in organic solvents were evaluated by using a paper electrophoresis and a conductometric titration. Nitrobenzene solutions containing trioctylmethylammonium chloride (TOMACl), thiocyanate (TOMASCN), nitrate (TOMANO₃) and perchlorate (TOMAClO₄) were used as impregnating solutions for the paper electrophoresis. The 0.1 M TPTCl nitrobenzene solution was spotted on the filter paper impregnated with the nitrobenzene solution of above quaternary ammonium salts. After electrophoresis, the TPTCl spots on the filter paper was detected by spraying a mercury(I) nitrate solution which leads color development. The TPTCl spot migrated toward the anode during electrophoresis when TOMACl and TOMASCN were used as supporting electrolytes. The migration distance of TPTCl spots was proportional to the elapse of electrophoresis time. On the other hand, in the case that TOMANO₃ and TOMAClO₄ were used as supporting electrolytes, the TPTCl spots did not migrate from the originally spotted point. These results indicate that TPTCl behaves as an anion which presumably due to that Cl^- and SCN^- ions coordinate to TPTCl to form anionic adducts in nitrobenzene, whereas TPTCl behaves as a neutral species in the TOMANO₃ and TOMAClO₄ solutions because of no interaction of TPTCl with NO₃^- and ClO₄^- ions. In the conductometric titration, a nitrobenzene solution containing 0.1 M TOMACl, TOMASCN, TOMANO₃ or TOMAClO₄ was titrated with a nitrobenzene solution containing 10^-2 M TOTCl. A steep decrease in electric conductivity was observed by adding the TPTCl solution until the amount of TPTCl was equal to that of TOMACl or TOMASCN in the case of titration of the TOMACl and TOMASCN solutions. No significant change in conductivity was observed in the titration of the TOMANO₃ and TOMAClO₄ solutions. An equivalent relationship between the amount of TPTCl and Cl^- or SCN^- ion indicates that the Cl^- or SCN^- ion coordinates to TPTCl to form a 1:1 complex, TPTCl₂^- or TPTClSCN^-, in nitrobenzene, which supports the findings in the electrophoresis experiments. It can be concluded that no interaction exists between TPTCl and NO₃^- and ClO₄^- from the electrophoresis and the conductometric titration.

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The activity of γ-glutamyltranspeptidase (γGTP) in serum was determined by measuring the increase in current for a given time due to the oxidation of 5-aminosalicylic acid, as enzymatically released from γ-glutamyl-3-carboxy-4-hydroxyanilide in Tris buffer of pH 8.5 containing glycylglycine, with a dialysis membrane-covered glassy-carbon electrode. The activities determined amperometrically for twenty six serum samples were in excellent agreement with those determined by a colorimetric method using γ-glutamyl-p-nitroanilide as the substrate (with the correlation coefficient of 0.997). The electrode was free of deactivation of electrode surface by the protein adsorption typically encountered when an electrode without a dialysis membrane was employed.

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Procedures for the curcumin photometric determination of both acid soluble and insoluble boron in nickel base heat resistant alloys were studied. The sample was dissolved in sulfuric acid. Insoluble boron could be quantitatively recovered by filtering through a filter paper No. 5C or a membrane filter with pore size under 0.45 μm. Addition of glycerine was proved to be effective to prevent volatilization loss of boron during evaporation of sample solutions. The procedure was applied to nickel base alloys. The sum of soluble and insoluble boron obtained by this method was in good agreement with total boron determined separately.

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