An barrier discharge radiofrequency helium glow-dischage plasma for the determination of fluorine, chlorine, bromine and iodine with atomic-emission spectroscopy was developed. A glass tube wrapped with two copper film electrodes, one of which was earthed and the other supplied with a radiofrequency impulse high voltage (98 kHz, 3.2 kV), maintained a glow discharge with a stream of helium gas. The emission was monitored by a spectrometer using a charge-coupled device (CCD) in the range of 730∼960 nm. The emission lines of fluorine (733.2, 739.9 nm), chlorine (833.3, 837.6, 858.6, 894.8, 912.1 nm etc.), bromine (827.2, 882.5, 889.8, 926.5 nm etc.) and iodine (905.8 nm) were determined. A linear calibration of 1∼10 μg for fluorine, and chlorine, and 0.1∼1 μg for bromine were achieved. The emission intensity was stronger in the order of bromine>iodine>chlorine>fluorine.

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The ¹H-, ¹³C- and ¹¹⁹Sn-NMR spectra of tri(n-butyl) (1-indenyl)tin(IV), di(n-butyl)bis(1-indenyl)tin(IV) and n-butyltris(1-indenyl)tin(IV) compounds were measured at low temperature. Assignments of the chemical shifts for ¹H-, ¹³C- and ¹¹⁹Sn in those compounds were obtained by means of carbon-hydrogen correlation spectroscopy(C-H COSY). The a-, b- and c-carbon of the n-butyl group signals for two stereoisomers (S,S and R,S) in the di(n-butyl)bis(1-indenyl)tin(IV) compound were separated into three signals, with a relative signal intensity of 1 : 2 : 1; the C₁, C₂, C₃ and C₈ carbons were separated into two signals. The C₁, C₄, C₅ and C₉ carbons for two stereoisomers(S,S,S and S,S,R) in the n-butyltris(1-indenyl)tin(IV) compound were separated into four signals, respectively. These results were considered to show that the separated signals were caused by being magnetically nonequivalent in the two stereoisomers.

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A new procedure for the determination of a sub μg g^-1 level of elements in high-purity iron has been developed. The sample was decomposed and prepared in a single test tube (made by PFA) to simplify and shorten the operation, which decreased the contamination from the reagents, circumstance and operators. More than 20 elements, such as Mn, Co, W, and Mo (more than 2 methods were needed for the analysis of these elements in steel), could be separated from an iron matrix in a 1 M hydrofluoric acid solution using the cumulated bed of cation- and anion-exchange resins that were packed in a single mini-column. The elements adsorbed on the resin were eluted by a HNO₃+H₂O₂ solution and determined by ICP-MS simultaneously. For the analysis of Al, V, Se, and Be, which were eluted with iron, HCl was added to the eluent and the solution was passed through an anion-exchange column to remove the iron matrix. The lower limit of a determination based on 10σ of blank values was below 0.1 μg/g for high-purity iron by using the present method.

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The flash-point measurement method provided by Japanese Industrial Standard (JIS) requires a 50 ml portion of the sample. However, the amount of the sample which can be used for crime detection is small. Therefore, a flash-point measurement cannot often be carried out by the JIS method. In routine work, the GC spectrum was measured to determine the types of petroleum in a sample. If the flash-point can be determined by the GC spectrum, information about the flash-point can be obtained from a small sample and the obtained value can be used as the presumed flash-point for the JIS method. A multivariate analysis was used to presume the flash-point. As a result, a calculation result based on GC corresponded to the measurement result by JIS extremely well.

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The selective determination of inorganic arsenic(III, V) and total organic arsenic in high salts wastewater by graphite-furnace AAS has been developed. The selective separation of inorganic arsenic in the presence of dimethylarsinic acid, monomethylarsonic acid and p-aminophenylarsonic acid was achieved by lanthanum hydroxide coprecipitation at pH 12 or more. Organic arsenic compounds were distilled as chloroarsine compounds by reductive distillation using tin(II) chloride under 2.75 M H₂SO₄ and 4 M HCl. The developed method was satisfactorily applied to real high salts wastewater. The detection limits(3σ) were 0.3 μg dm^-3 for inorganic arsenic and 2.3 μg dm^-3 for organic arsenic.

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A rapid and simple preconcentration method by selective adsorptation using silica gel loaded with Xylenol Orange(XO)/trioctylmethylammonum chloride(capriquat) is described for the determination of a trace amount of beryllium by graphite-furnace AAS(GF-AAS). A sample solution of 100∼2300 ml containing Be was adjusted to pH 8. The solution was then passed through a column packed with 100 mg of XO/capriquat-loaded in silica gel at a flow rate of 5 ml/min. The Be collected on the XO/capriquat-loaded silica gel column was eluted with 5 ml of 0.5 M nitric acid, and then determinated by GF-AAS. The calibration curve was linear over the range 0 to 0.1 μg/5 ml of Be. This method can be applied to the determination of trace amouns of Be in seawater samples.

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Usually, the preferred sample measurement method in forensic science is non-destructive, rather than destructive. Only one non-destructive method, however, provides limited information about the sample. To examine similarities among samples, it has been necessary to analyze a combination of results from different methods. Thus, in the presence study, analytical data from an X-ray fluorescence method, an X-ray diffraction method and diffuse-reflectance infrared Fourier-transform spectroscopy were performed using a multivariate analysis to classify the magnetic record media, such as a prepaid card and a train ticket. Eighty-six samples were classified into six groups by the X-ray fluorescence method and diffuse-reflectance infrared Fourier-transform spectroscopy and into 3 groups by the X-ray diffraction method. Combined with three analytical data, a more detailed discrimination of the samples was possible.

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Trace amounts of boron in river-water samples were determined by a combined method of anion-exchange preconcentration and ICP-AES. A river-water sample was acidified to 0.1 mol dm^-3 or 0.2 mol dm^-3 with hydrofluoric acid. The sample was permitted to stand for 1 h and then passed through an anion-exchange column(Bio-Rad, AG1-X8, 100∼200 mesh, F form, 3 g) at a flow rate of about 1 cm³ min^-1. The boron adsorbed on the ion exchange column was washed with 20 cm³ of 1 mol dm^-3 nitric acid, and then eluted with 20 cm³ of 6.5 mol dm^-3 nitric acid. After the effluent was collected in a 100 cm³ quartz beaker, 10 cm³ of 1.47 mol dm^-3 H₃PO₄ was added and evaporated to about 2 cm³ on a hotplate. Any organic materials in the effluent were decomposed with mixed H₃PO₄-HClO₄-HNO₃. The content in the beaker was then transfered a 25 cm³ PTFE standard flask, and diluted to the mark with water. The boron contents were determined by ICP-AES(182.6 nm). The present method was successfully applied to the analysis of standard reference materials(JAC0032) and to samples from Doshi river. The determination of boron in the standard reference materials showed good agreement and precision with already published values. The boron contents in the upper, middle and lower reaches in the river were 3.5±0.1 μg/l (n=3), 5.1±0.1 μg/l (n=6) and 9.4±0.6 μg/l (n=4), respectively.

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On-line size exclusion chromatography/nuclear magnetic resonance (SEC/NMR) has been applied to the characterization of polymers. In this study, on-line SEC/NMR was applied to an analysis of silicone, and a suitable condition for determining the molecular weight dependence of the functional groups in silicone was investigated. Deuterated chloroform was used as an eluent, the flow rate was 0.04 ml/min. The amount of sample was 10 mg. A presaturation method was used to reduce the highest signal due to SiCH₃. The ¹H-NMR spectra were collected every 225 s. Each spectrum was obtained by the accumulation of 420 scans. By on-line SEC/NMR using the above-mentioned condition, a distribution analysis of 10^-5 eq./g order of functional groups in silicone has become feasible. It was also found that the times required for a sample treatment and an analysis were 1/30 and 1/3 of the off-line time, respectively. Applications to the analysis of adhesives have proved that this method is useful for the analysis of silicone.

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Stream water samples were obtained in duplicate at 8 sites on the Tibetan Plateau (29°15'-31°53'E, 85°03'-91°48'N) during the GAME-Tibet IOP project from May 7-22, 1998, as well as one sample from a salt lake at a north-eastern site. Ion chromatography, atomic absorption spectrometry, ICP/MS and chemiluminescence were applied to determine the major and minor chemical species. The pH, EC and concentrations of Cl^-, SO₄^2-, Na⁺, K⁺, Ca²⁺, Mg²⁺, SiO₂, F^-, Sr²⁺, Ba²⁺, Ni²⁺, Cu²⁺, NO₃^-, NH₄⁺, DON are shown. The concentrations of SO₄^2-, Sr²⁺ and Ba²⁺ were found to be higher in the western part of the sampling sites, while those of NO₃^-, DON and Mn were higher at eastern sites. The concentration of Ca²⁺ was fairy uniform, while those of Na⁺, K⁺ and SiO₂ ranged widely without any clear geographical tendencies.

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Temperature-programmed analytical pyrolysis (TPPy) techniques were developed for the characterization of various functional polymers. In the first study, the TPPy techniques were applied to investigate the thermal-degradation process of a flame-retarded poly (buthylene terephthalate) (FR-PBT) with a synergistic flame-retardant system based on a bromine-containing polycarbonate (Br-PC) and Sb₂O₃. It was clarified that during the degradation of FR-PBT the evolution of various bromine-containing products, including flame-poisoning SbBr₃ formed through the reaction between Br-PC and Sb₂O₃, were closely related to synergistic flame-retarding mechanisms. In a second study, a natural polysaccharide chitin/chitosan and chitin-based polymer hybrids were characterized by means of analytical pyrolysis techniques. Firstly, in order to determine the composition of N-acetyl-D-glucosamine units (i.e. the degree of acetylation) of chitin/chitosan, a new reactive pyrolysis-gas chromatography in the presence of an oxalic acid aqueous solution was developed. The proposed technique was applicable to any kind of chitin/chitosan sample over the whole range of acetylation to which the other individual methods were inapplicable. Secondly, novel chitin-based polymer blends with a chitin derivative and poly (vinyl chloride) were characterized by the TPPy techniques. The evolution peak-top temperatures and the amounts of the characteristic degradation products were correlated to the miscibility of the blends. In addition, the mechanisms for the intermolecular interaction of the blends were also characterized.

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