This paper is comprised of 4 chapters describing; the observations of atomic distributions in the flame, atomic absorption in the aqueous phase, ozone chemiluminescence with hydride generation technique, and techniques for enhancing sensitivity in absorption spectrometry.
In the second chapter, distribution of atoms in atomic absorption flames (air-acetylene and nitrous oxide-acetylene flames) is discussed, where atomic absorption intensities of several elements were observed in different parts of flame under various conditions. These distributions were presented as coordinates of which abscissa and ordinate express fuel (acetylene) flow rate and observation height above the burner, respectively. This presentation makes it possible to illustrate the effects of chemical factors influencing the atomic distribution in the flame, i.e., dissociation energies of mono-oxides and mono-halides of the analytes are one of the essential factors in determining the atomic distribution in the flame. Also, 50 inorganic complexes of Cr, Mn, Fe, Co, Ni, and Cu were nebulized into the air-acetylene flame and ligand effects on the atomic distributions of these elements are discussed.
In the third chapter, the possibility of observing atomic absorption in the aqueous solution was discussed. Spectroscopic observation made on the surface of the electrode during the reduction of metal ions by electrolysis did not give any atomic absorption spectrum, which has been previously suggested by Tyson and West. Thus we tried to measure the absorption spectrum in the aqueous solution of Hg(I) and Hg(II) just after the addition of reducing agents such as Sn²⁺, SO₃^2-, and NaBH₄. A transient absorption spectrum appeared, which gave a peak located around 243.7 nm. This spectrum provided a doublet structure. These characteristics are successfully explained as a absorption spectrum of hydrated mercury atom.
The fourth chapter discusses gas-phase chemiluminescences for the detection of arsenic, antinomy, tin, and selenium. The hydride generation technique, which has been developed for atomic absorption spectrometry of these elements, was combined with the ozone chemiluminescence which has been originally used for detecting NO_x. This combination resulted in a sensitive analytical method especially for arsenic (detection limit of arsenic is 0.15 ng or 3 ppt). In addition, the hydride generation technique was also mentioned for the quantitative generation of phosphine from phosphate ion, which has been previously difficult to be executed. Phosphate solution was mixed with NaBH₄ and dried at 40°C on a quartz boat, and then heated at 430°C in the helium flow. This technique gives a consistent conversion of phosphate to phosphine (conversion rate : 43%). Coupling with a FPD-gas chromatography, 100 pg of P as phosphate can be analyzed.
The fifth chapter discribes the techniques which bring about the high sensitivity in absorption spectrometry. Laser induced thermal lensing colorimetry was applied to the determination of nitrite and phosphate ions, where a single cw laser was doubly used as a probe and a source. The accumulation and averaging of the photo-signals were done by a handmade system with a commercial computer or by a transient recorder/signal averager system.
Furthermore, a long capillary cell(LCC) technique was mentioned. In Lambert-Beer's law, extension of the light pathlength provides an increase in absorbance. Therefore, we constructed a 1 m linear shaped LCC, which gave up to 300 times the amplification in absorbance compared to ordinary cells.

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A simple and rapid procedure for the flame photometric determination of tin using an inverted-flame burner has been studied. The flame emission band spectra, originating from SnH molecule, have a strong band head at 609.5 nm. This band head can be used for the analysis of tin in antifouling paints (A/F). The procedure is as follows : To prevent evaporation loss of tin, wet decomposition of the sample with a mixture of hydrochloric and nitric acids (3 : 1) was performed in a 100 ml Kjeldahl flask equipped with a 35 cm-condenser. The resulting solution was filtered through Toyo-5B filter paper and diluted to 100 ml with 1 M-hydrochloric acid. The band head height of flame emission spectra of SnH was measured in a strongly reductive hydrogen flame at 609.5 nm, and the content of tin in antifouling paints was determined by the method of standard addition.

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Twenty to forty mgs silicate samples (olivine megacrysts, meteorites, and standard rocks) were weighed, wrapped in aluminium foil, and irradiated with a flux of 8×10¹³ n cm^-2 s^-1 for 40 min in JRR-4 of JAERI, along with a standard sample. After cooling, the sample was fused with sodium peroxide and sodium hydroxide in a zirconium crucible containing the potassium carrier. The resulted cake was dissolved with water. After centrifugation, the supernatant was roughly neutralized. Potassium precipitated as potassium tetraphenylborate was collected on filter paper, washed, dried, weighed, and wrapped with cellophane tape. A photopeak of 1525 keV of neutron-induced ⁴²K was used for the determination of potassium. Chemical yields were checked both by gravimetrical and reactivation methods. The gravimetrical method gave systematically larger values than those obtained by the reactivation method. The factor varies from 1.04 to 1.42. This might suggest that some elements were coprecipitated with potassium. Analytical results of potassium for standard rocks, JB-1 and JP-1, were in good agreement with the literature values. The lowest value of potassium in silicate materials determined in this study was 4.3 ppm for an olivine megacryst sample. Based on the gamma-spectrum of this sample, the detection limit of potassium for this method was deduced to be 370 ppb for a sample size of 30 mg. Several sources of errors accompanied with the present method were examined and their maximum estimates were calculated.

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A method is presented for quantitative particle induced X-ray emission (PIXE) analysis of impurities inthe thick samples of silicon nitride. In the analysis of ceramic materials such as silicon nitride, chemical treatments are required to prepare thin enough samples. However, the chemical treatments are undesirable for the PIXE analysis, because another complications are brought about. Our method does not need any chemical treatments and thick samples can be subjected to the measurements. The determination of impurities were made by on-line use of a personal computer in which standard X-ray intensity data were stored. The method and procedures are as follows: After subtracting a buckground spectrum from an observed PIXE spectrum, the resultant peaks are assigned to individual elements. Then, in order to determine the contents of the impurities, the intensity of each peak is compared with a Gaussian curve which is generated from the standard X-ray intensity data. The latter data were determined theoretically. The results were in satisfactory agreement with those obtained by ICP emission spectrometry.

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Photoacoustic determination of the glucose concentrations was conducted by using a multilayered film as a probe material for dyeing. A small amount (about 2.5 μl) of glucose solution with various concentrations (04 g/l) was dropped on one side of the film. The glucose solution permeated through the layers of the film to reach the reagent layer where the dyeing reaction occured. The dyestuff showed a characteristic absorption peak at 500 nm, and light from xenon lamp with wavelengths between 460800 was used for exciting the dyestuff. The photoacoustic signal from the other side of the film was detected. The signal intensity was found to be linear in the range from 0 to 2 g/l. This method was applied to the measurement of the glucose concentration of human blood, and was found to give somewhat higher values compared to those by mutarotase GOD method, the standard method for glucose determination. It can serve, however, as a rapid and simple diagnosis of diabetes.

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A new analytical method for the determination of a micro amount of nitrite ion in water samples was investigated by reversed phase ion pair chromatography with an amperometric detector, the working electrode of which was made of grassy carbon. Chromatographic conditions were as follows : column; Shodex IC I-613 (150 mm×6 mm i. d.), eluent; 1 mM phthalic acid, 0.35 mM tetra-n-butylammonium hydroxide, 0.5(v/v)% tetrahydrofuran, pH; 3.50, flow rate; 1.2 ml/min, applied voltage; 1000 mV vs. silver/ silver chloride, sample size; 100 μl. A micro amount of nitrite ion could be determined using this methodwithout the influence of high concentration of chloride ion, nitrate ion and sulfate ion. The detection limit was 3 ng/ml for nitrite ion. This method was about five hundred times more sensitive than the method of ion chromatography using a conductivity detector. The relative standard deviation was 2.6% (n=10) at the nitrite ion level of 100 ng/ml. The proposed method was applied to the determination of nitrite ion in samples of snow water, rain water and well water.

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An emission analysis for the determination of trace metals by the nitrogen afterglow is discussed. A dielectric discharge generator was employed as an excited nitrogen source. Metal salts deposited on a tantalum boat from aqueous solutions were dried in vacuo and were vaporized electrothermally. The analyte vapor was introduced into the flowing reaction cell and was excited by energy transfer from excited nitrogen molecules, mainly at the metastable triplet state N₂(A³Σ⁺_u). Detection limits for zinc (472.2 nm line), cadmium (326.1 nm line), and mercury (253.7 nm line) were determined to be 5, 0.1, 0.03 ng, respectively. Effects of anions on calibration curves were studied by employing metal nitrate, sulfate, and chloride. Calibration curves for cadmium salts were not affected by anions. Zinc and mercury chlorides gave weaker signals than salts with other anions. This may suggest that these chloride salts are not sufficiently dissociated. Mercury(II) nitrate could not give the calibration curve, because the signal from mercury had significant amount of noise. This is due to the spectral interference from the γ-emission band of nitrogen monoxide produced from nitrate ion. The influence of acid concentration on peak height of title elements was studied by varying the concentration up to 0.8 M. As the concentration of acid increased, sulfuric acid and hydrochloric acid reduces the peak height, but nitric acid increased it. This suggestes that the vapor of sulfuric or hydrochloric acid is a quencher of N₂(A³Σ⁺_u) and nitric acid vapor effectively works during the energy transfer process. However, the reproducibility of peak height became poor at high concentrations of all acids. This may be caused by the change in the surface state of the tantalum atomizer.

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Liquid ionization(LI) mass spectrometry was applied to the analysis of following cationic and amphoteric surfactants; aliphatic amine salts, tetraalkylammonium salts, benzylammonium salts, alkylpyridinium salts, betaine and imidazoline type amphoteric surfactants LI mass spectra exhibited quaternary ammonium ions (molecular cation) for cationic surfactants and protonated molecules(MH⁺) for amphoteric surfactants. Main fragmentation process is loss of one substituent attached to the ammonium nitrogen as an alkyl halide followed by protonation. Both molecular weight and structural information were obtained from LI mass spectra. This method can be applied to a direct analysis of a mixture. Comparisons of fragmentation processes in several soft ionization methods were also made.

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This report describes preparation of niobium and tantalum standard solutions for ICP atomic emission spectrometry. A mixture of 2 ml nitric acid (1+1), 1 ml hydrofluoric acid (1+1) and 4 ml sulfuric acid (1+1) was used to dissolve 200 mg of niobium or tantalum metal powder, and the solution obtained was evaporated till sulfuric acid began fuming. The resulting syrupy residue was dissolved in a solution containing a necessary amount of complexing reagent, filtered if precipitate appeared and finally made up to 200 ml. As complexing reagents, ammonium ox alate, tartaric acid, hydrofluoric acid, hydrogen peroxide and sulfuric acid were tested to evaluate their stabilizing effects on niobium and tantalum solutions. As a result, following reagents and concentrations were recommended for preparation of 1 mg ml^-1 stock solution of each element: For niobium, 0.1 M ammonium oxalate, 0.6 M tartaric acid or 2% hydrogen peroxide plus 0.5 M sulfuric acid; for tantalum, 0.1 M ammonium oxalate, 1.2 M tartaric acid or 0.025 M hydrofluoric acid. The stock solutions thus prepared could be preserved more than one year without precipitation, though the concentrations of the complexing reagents were much lower as compared with those of conventional standard solutions used for colorimetry. Working standard solutions prepared by diluting the stock solutions ten-fold with water were stable as well. The complexing reagents had negligible interferences on the emission intensities of niobium and tantalum.

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On the basis of the coloration of molybdophosphate with Guinea Green B in an aqueous solution, trace amounts of phosphorus were determined. The recommended procedure was as follows. The solution was acidified with sulfuric acid to pH 2 and filtered through a membrane filter (pore size 0.45 μm). A 20ml portion of the filtrate was mixed with 1 ml of 7.5 M sulfuric acid and heated above 90°C for 45 min to hydrolyze condensed phosphates to orthophosphate. When cooled, the solution was transfered into a 25ml measuring flask, admixed with 2 ml of molybdate solution (molybdenum: 0.5 M, sulfuric acid: 2.5 M) and 1 ml of 3×10^-3 M Guinea Green B aqueous solution, and diluted to the mark with distilled water. The absorbance at 630 nm was measured after 1 h. The calibration curve was linear at phosphorus concentration below 240 ppb and the detection limit was 1 ppb. The molar absorptivity was 1.3×10⁵ 1 mol^-1 cm^-1 at 630 nm. The relative standard deviation for the ten determinations of phosphorus at 40 ppb level was 0.4%. Diverse ions commonly found in river waters did not interfere with the determination of phosphorus. The method was applied to the determination of total phosphorus existing as orthophosphate and condensed phosphates in river and tap waters. The recoveries tested by standard addition were within 99103%.

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A method has been proposed to predict the retention indices(RI) of the title compounds under various separation conditions. When the presence of thiols or sulfides was confirmed by the subtraction or the shift of peaks, respectively, by means of the tandem combination of a post column reactor coated with silver nitrate and a flame photometric detector, a certain thiol or sulfide was chosen as the standard compound. The retention characteristics of the stationary phase for the particular type of compound were estimated from the RI of the standard. The RI of these types of compound could be predicted accurately by using the observed RI value of the standard and the RI values of the compound of interest on the couple of the stationary phases (polyethylene glycol 20M at 80°C and silicone oil DC-550 at 70°C). The contribution of the increments due to the atomic groups was added in calculation of the latter RI values.

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An organic elemental analyzer with the differential thermal conductivity method for carbon, hydrogen, and nitrogen determination was applied to the analysis of thin films of amorphous silicon. The analytical values were compared with those obtained by gas analysis method for metal as the standards. In the case of hydrogen determination for silicon hydride by this method, (1) the bias was ±0.000.15 wt%, and the relative standard deviation (n=9) was 2.66.7%, both at 0.500.80 wt% hydrogen content, and (2) with 5 mg of samples, the determination limit, namely, 10 times the standard deviation was 0.007 wt%. However, the bias of hydrogen determination for silicon hydride nitride was -0.18 wt% at 1.14 wt% hydrogen content. There were large minus errors in the cases of nitrogen determination for silicon hydride nitride, and of hydrogen and carbon determination for silicon hydride carbide.

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Determination of moisture in amines by Karl Fischer coulometric titration was studied. Measurements were carried out in the commercial anolyte to which salicylic acid had been added as a neutralizer. The amines, the moisture in which could not be determined by the present method, were classified into the following groups; 1) aliphatic diamine compounds, 2) aromatic diamine compounds and 3) the compounds in which amino groups bind to benzene neucleus. In case 2), the oxidation of the amines at the anode seems to be the reason why they could not be determined. In cases 1) and 3), the reaction of amines with iodine generated electrolytically may be the reason. For other amines, irrespective of their pK_a, values, the moisture contained in them could be determined by the present method. Good agreements were found between the results by the present method and those by the volumetric titration method.

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Concerning waste water from a laundry machine, use of gas detector tube has been applied to the determination of very small amount of tetrachloroethylene(TCE). In Japan, two kinds of detector tubes for TCE with relatively low sensitivity can be purchased, one is {No. 135S (5300 ppm)} and the other is No. 133 (50250 ppm). However, detector tube for trichloroethylene made by Kitazawa Co. {No. 132L (225 ppm)} is developed to be useful for the determination of TCE with very high sensitivity. For the analysis, 200 ml of water containing TCE is taken in 500 ml stoppered glass bottle. After shaking, 50 ml of the equilibrated air in the head space is passed through the detector tube (No. 132L) by means of a disposal syringe. Concentration of TCE in water is then calculated by using Henry's constant and the calibration curve for TCE obtained by separate experiments. The detection limit of a gas detector tube is 0.3 ppm, while Henry's constant expressed by ppm TCE in air/ppm TCE in water attains the value of about 70. Consequently the limit of detec tion of TCE in water is about 0.01 mg/l.

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Phosphorus can be determined in the process of multi element analyses by ICP emission spectrometry and of anion determination by ion chromatography. Though the sensitivities of these methods for phosphorus are found to be inferior to that of spectrophotometry, these methods can provide the informations on other chemical components in single operations. From these point of view, the detailed conditions for analysis were examined to find out good recoveries and consistencies with spectrophotometry. NBS standard reference materials, Estuarine Sediment and Urban Particulate Matter were used to check the extraction process. Then, these methods were applied to the determination of phosphorus in the airborne particles at Tsukuba Science City. Some characteristic features were found in its concentrations in various seasons and in different particle sizes. The difference between the concentrations found in the surface air and those in 175 m stage of the Meteorological Observation Tower (213 m) were also shown with some discussions.

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