The NMR spectra of phenols in aqueous acetone solution gave broadened signals of their OH protons as the result of proton exchange between the OH group and the H₂O molecule. But both the OH and H₂O protons gave well resolved signals in the presence of small amounts of metallic salts and the signals were shifted towards the low field. The shift values of the OH and H₂O protons varied greatly depending on the quantity of water and kind of phenol; phenols with smaller pK_a's gave larger shift values. In this case, the difference of the shift values between OH and H₂O protons increased with increasing the amount of water added. This result is contrary to the general explanation that the both signals of OH and H₂O protons approach to each other and overlap under the influence of proton exchange. The result mentioned above was considered to be due to the following mechanism: Phenols are dissociated into [H₃O] ⁺ and the phenoxide ion by the addition of water. Because this phenoxide ion has intense affinity to OH protons, the strong hydrogen bonds are formed between the OH group and the phenoxide ion. Accordingly, the signals of the OH protons are shifted towards the low field.

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The reaction between slightly hydrolyzed zirconium oxychloride and Xylenol Orange (XO) is catalyzed by the presence of micro amounts of fluoride. Based on the catalytic effect Cabello-Tomas et al. have reported a spectrophotometric method for the determination of fluoride. Addition of the cetyltrimethylammonium chloride (CTC) as a surfactant to the Zr-XO complex resulted in giving a bathochromic shift as well as a remarkable increase in absorbance. By the aid of CTC, a more sensitive method has been developed for the determination of ultramicro amounts of fluoride based on the above catalytic reaction. The analytical procedure was as follows. A 10 cm³ aliquot of the sample solution containing less than 100 ppb of fluoride, 1 cm³ of 2 × 10^-4 mol dm^-3 XO and 1 cm³ of 0.1 % CTC solution (in 3.00 mol dm^-3 HCl) were placed in a test tube. One cubic centimeter of 2 × 10^-4 mol dm^-3 slightly hydrolyzed zirconium solution (in 0.02 mol dm^-3 HCl) was then added to the solution and the test tube placed in a water bath at 25 °C. The absorbance was measured at 605 nm againstwater at 40 min after the addition of the slightly hydrolyzed zirconium solution. By this method, fluoride ion ranging from 5 ppb to 100 ppb can be determined. Sulfate, phosphate, aluminum and iron (III) showed interferences in this method. The proposed method was applied to the determination of fluoride separated from water samples (tap and well water) by a microdiffusion method using hexamethyldisiloxane.

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Since perylene, naphthacene, anthracene, carbazole, dibenzofuran, acenaphthene, and fluorene show sensitive synchronous fluorescence signals with a narrow wavelength interval, these compounds can be determined by the synchronous fluorescence method. The suitable wavelength intervals were 3 nm for perylene, naphthacene, anthracene, and carbazole, 6 nm for dibenzofuran and fluorene, 7 nm for acenaphthene, using cyclohexane as the solvent. To evaluate the applicability to multicomponent samples, the interferences of 16 polynuclear aromatic compounds (perylene, fluorene, anthracene, naphthacene, carbazole, dibenzofuran, acenaphthene, chrycene, phenanthrene, pyrene, fluoranthene, biphenyl, naphthalene, anthraquinone, phenanthrenequinone, and 9-fluorenone) were examined. From these results, this method could be applied to the simultaneous determination of carbazole and anthracene in phenanthrene. The synchronous fluorescence intensities of carbazole and anthracene at 333 nm and 377 nm were measured using a sample solution containing 50 μg/ml. The calibration curves for carbazole and anthracene were prepared in the presence of 50 μg/ml phenanthrene. The determination limits of carbazole and anthracene were 0.1 % and 0.05 %, respectively.

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The gas chromatographic separation and determination of palladium in the mixture of platinum group metals was investigated with a gas chromatograph equipped with a ligand vapor generator, using 10 % PPE-6R (polyphenyl ether 6 rings) as the stationary liquid phase at the column temperature of 140 °C and at the flow rate of 30 ml/min. To an aqueous solution of the mixture of platinum group metals, Htfa (trifluoroacetylacetone) was added, the chelates formed at pH 5.58 were extracted with chloroform, and the definite volume of the organic phase was injected to the gas chromatograph. It was found that palladium in the mixture of platinum group metals could be rapidly and easily determined with an average recovery of 96.2 % and a relative standard deviation of 0.99 %. Moreover, satisfactory result was obtained in the analysis of a real sample.

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Atomic absorption spectrometry using a carbon tube atomizer was applied for the determination of ytterbium in phosphate minerals such as xenotime, monazite, and apatite. A constant absorption signal of ytterbium was observed above ca. 2650 °C in carbon tube. In the present experiments, the carbon tube atomizer was operated at an atomizing temperature of ca. 2700 °C where the current was 300 A for 10 s. In the ytterbium concentration range of (1040) ppb in the sample solution, a fairly linear calibration curve was obtained. when 10 μl of the solution was injected. The sensitivity (1 % absorption) was 1.35 ppb, and the R. S. D was ca. 7 %. The effect of coexisting salts on the peak absorbance of ytterbium was examined with regard to the solution of 35 ppb ytterbium containing (10¹10⁴) times equivalent amounts of the salts. The peak absorbance of ytterbium was only slightly affected by (10¹10³) times equivalent amounts, but by 10⁴ fold amounts, most salts interfered. Phosphate minerals were treated with hot concentrated sulfuric or nitric acid. After any insoluble residue was filtered, the filtrate was diluted with water until the concentration reached to (120)μg/ml with respect to xenotime or monazite. Ten microliters of these sample solutions were directly injected into the carbon tube atomizer. By this analysis, the content of ytterbium in these minerals was found to be (0.192.18) %. However, direct determination of ytterbium in calcium apatite mineral was difficult because of an interference of calcium ions. Therefore, ytterbium content in such an apatite was determined after ytterbium extracted from 10 M perchloric acid containing 0.1 M di-(2-ethylhexyl) phosphate (HDEHP) into cyclohexane, the amount found was in the range of the 2.26 × 10^-3 % to 2.56 × 10^-3 %.

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The Kitakyushu Municipal Institute of Environmental Health SciencesGas chromatographic (GC) determination of 2, 2, 4-trimethy1-1, 2-dihydroquinoline (TMDQ) and 6-ethoxy-2, 2, 4-trimethyl-1, 2-dihydroquinoline (ETMDQ) in environmental samples was developed. The GC conditions were as follows : column, 3 % PZ-179 on (6080) mesh Uniport HPS, 2 mm i. d. × 2 m for FID-GC and 2 mm i. d. × 1.8 m for FTD-GC, glass; injector temperature, 250 °C; column temperature, 210 °C for FID-GC and 190 °C for FTD-GC; detector temperature, 300 °C; carrier gas, nitrogen gas 40 ml min^-1. The analytical procedures were as follows. In case of water sample, TMDQ and ETMDQ were extracted 3 times with 100 ml, 50 ml and 50 ml of hexane from 1l of sample by shaking for 10 min after adjustment of the pH to above 5.0 with Na₂CO₃. The hexane layers were combined and then TMDQ and ETMDQ were back-extracted 3 times with 50 ml, 25 ml and 25 ml of 2 N HCl solution from the hexane layer. The HCl layers were combined and TMDQ and ETMDQ were re-extracted 3 times with 50 ml, 25 ml and 25 ml of hexane after the HCl layer had been alkalized with 25 ml of 10 N NaOH solution. The extract was washed 3 times with each of 25 ml of water, dried over anhydrous Na₂SO₄, concentrated to 2 ml, and analyzed by GC. In case of sediment, TMDQ and ETMDQ were extracted twice with each of 100 ml of acetone from 50g of sample by shaking for 30 min after adjustment of the pH to above 5.0 with Na₂CO₃. The acetone solution was filtrated and filled up to 250 ml with acetone. To 100 ml of the filtrate was added 200 ml of water, and then TMDQ and ETMDQ were extracted twice with each of 100 ml of hexane. The extract was washed twice with each of 100 ml of water and treated in the same manner as for water sample. Recoveries fortified in the range between 200 μg and 400 μg were (8689) % for TMDQ and (7485) % for ETMDQ, and in the range between 1 μg and 50 μg were (2483) % and (334) %, respectively. TMDQ and ETMDQ were changeable in quality during the operation and GC analysis, and produced 2, 4-dimethylquinoline and 6-ethoxy-2, 4-dimethylquinoline, respectively. These changes and the adsorption on the vessel wall etc. gave the low recoveries at a low concentration. The detection limits were 0.5 ng ml^-1 for TMDQ and 2 ng ml^-1 for ETMDQ, in case of water sample, and 0.05 μg g^-1 and 0.5 μg g^-1 in case of sediment, respectively.

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As a simple analytical method, the capillary tube isotachophoresis was applied to the analysis of sodium chondroitin sulfate (ChnS) in cosmetic products. The best result was obtained with the acidic electrolyte system in which the leading electrolyte contained 0.01 M hydrochloride, β-alanine and Triton X-100 pH 3.2, and the terminal electrolyte contained 0.01 M caproic acid. In order to avoid interferences cosmetic products were extracted by using cetylpyridinium chloride. The recovery of ChnS from known samples was 92.4 % and the method was applicable to the qualitative and quantitative analysis of ChnS in commercial cosmetic products. Advantages of isotachophoresis in this field are as follows. 1) The sample can be injected directly. 2) Multiple ionic components can be analyzed simultaneously.

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A method is described for the determination of aromatic nitro compounds in air pollutants. Airborne particulates and diesel engine exhaust samples were collected on glass fiber filters by high volume air sam pler and organic compounds in the samples were extracted with benzene-methanol (4 : 1 v/v) by a Soxhlet extraction. The compounds extracted were separated into neutral, acidic and basic fractions. The neutral fraction was chromatographed on a silica gel column and divided into four portions. The aromatic nitro compounds were contained in the third fraction which was eluted with benzene and then, were converted to aromatic amines by the reduction with hydrochloric acid and zinc powder. The aromatic amines formed were extracted with benzene, and were converted to the acyl derivatives with heptafluorobutyric anhydride. The products were determined by means of gas chromatograph equipped with a ⁶³Ni electron capture detector. A glass column (2 m, 3 mm i. d.) of 3 % OV-17 on (80100) mesh Gas Chrom Q was operated at 250 °C with a detector at a temperature of 290 °C and a carrier gas (nitrogen) at a flow rate of 30 ml min^-1. The average recoveries obtained for 1.0 μg and 0.1 μg of 1-nitropyrene added to the aromatic nitro compounds fraction of the airborne particulate matters were 94.5 % and 91.9 %, respectively. The coef ficients of variation were within 5 % (n=4). 3-nitro-fluoranthene, 2, 7-dinitrofluorene, 4, 4'-dinitrobiphenyl, 2-nitrofluorene, 1-nitronaphthalene, and 2-nitrobiphenyl were analyzed by the same method. 1-Nitropyrene was detected in the diesel engine exhaust {8.6 μg/g (dust)} and airborne particulate matters in industrial area (20.8 pg/m³).

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Bis (2, 4-diaminophenyl) phosphonate (APP) oxidized by copper (II) was found to indicate red coloralation having an absorption maximum at 500 nm, and the fundamental conditions for the determination of copper (II) based on color development with the oxidation of APP were investigated. The optimum conditions were established by the use of the oxidation product obtained in aqueous 0.02 mol/l hydrochloric acid-40 v/v% ethanolic solution for 40 min at 50°C. Beer's law holds for (210)μg/50 ml of copper. The molar absorptibity and sensitivity for 0.001 absorbance were 4.93×10⁴ dm³ mo1^-1 cm^-1 and 1.29 × 10^-3 μg cm^-2, respectively. A small amount of several ions such as S₂O₃^2-, IO_3-, CrO₄^2- and Fe (III), interfered seriously with the determination. The established method could be applied to the determination cf copper in river water with satisfactory results.

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A simple and practical method for the determination of nitrite and nitrate in human milk and blood is described. The method is based on the nitration of 2-s-butylphenol, followed by the pentafluorobenzoylation to form pentafluorobenzoyl ester for nitrate determination and the formation of tetrazolophthalazine as reported in the previous paper for nitrite determination. Both products were extracted with benzene and simultaneously determined by the gas chromatography. The procedure was as follows : To 3 ml of blood sample, 1 ml of 1 N NaOH and 1 ml of 12 w/v % ZnSO₄ were added. The solution was well mixed for 1 min and centrifuged at 3000 rpm for 5 min. To 5 ml of human milk sample, 1 ml of deproteinization solution {a mixture of 8 w/v% HgCl₂, 9 w/v% NH₄-CN and 25 w/v% Zn (CH₃COO)₂} and 3 ml of distilled water were added, and the mixture was shaken for 1 min. To 1 ml of the filtrate, 1 ml of 5 w/v% Ag₂SO₄ and 3 ml of distilled water were added. Then, in a ice-bath 7 ml of sulfuric acid was added gently, and finally 0.1 ml of 2-s-butylphenol solution was added. After reaction for 15 min at room temperature with occasional shaking, the reaction mixture was extracted with 10 ml of toluene. The organic phase was washed twice with 10 ml of distilled water, then re-extracted with 10 ml of 5 w/v% Na₂CO₃. The alkaline solution was transferred into another separating funnel and 10 μl of pentafluorobenzoyl chloride was added. After reaction with shaking for 1 min, the content was extracted with 20 ml of benzene and dried with Na₂SO₄ (anhydrous). The supernatant phase (5 ml for human milk or 1 ml for blood) was transferred into another test tube for nitrite determination, and reacted as described peviously, and then extracted twice with 10 ml of ethyl ether and dried with Na₂SO₄ (anhydrous) and evaporated at 40 °C in a water-bath. To the dried residue was added 2.5 ml of benzene extract, and concentrated to 1 ml. An adequate volume of the final solution was injected into gas chromatograph. The average recoveries of nitrite and nitrate added to human milk and human blood plasma range from 95.4% to 97.8 % for nitrite and 91.1% to 98.5 % for nitrate. The mean concentration was 0.04 ppm for nitrite and 0.42 ppm for nitrate in fifty human milk samples, and was 0.04 ppm for nitrite and 0.76 ppm for nitrate in fifty human blood samples. The method allowed the determination of N-NO₂ in the concentration range (0.010.15)μg/ml and N-NO₃ in the concentration range (0.010.1) μg/ml and the detection limit was 0.01 ppm for nitrite and 0.05 ppm for nitrate in human milk, 0.004 ppm for nitrite and 0.02 ppm for nitrate in human blood.

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A gravimetric method for the determination of nickel with 2-hydroxy-1-naphthaldoxime (HNA) has been studied. Nickel is quantitatively precipitated from the solution of pH 49 as a green complex with HNA. The precipitate dried at 110 °C is confirmed to be Ni(HNA)₂ by elemental analysis and the gravimetric factor for nickel is 0.1362. The method is simple, rapid, sensitive and selective and gives coefficient of variation within 0.5 %. The recommended procedure is as follows : Take 200 ml of a sample solution containing (325) mg of nickel, add 15 ml of 4 M tartaric acid solution, adjust pH of the solution to 4.5 with sodium hydroxide solution, and dilute with water until about 300 ml. Heat nearly to boiling, add 18 ml of 1 % HNA in ethanol, and allow to stand for 1 h. The green precipitate thus obtained is filtered off on a G-4 sintered glass crucible, wash first with water and then with methanol to remove the excess reagent, and dried at 110 °C for 2 h. The method can successfully be applied to the determination of nickel in stainless steel and nichrome wire.

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A chelating reagent containing sulfur ligands, ammonium diisopropyldithiophosphinate, was synthesized and various metal ions were reacted with it to form the chelates. The thermal properties, the extractability into organic solvents and the gas chromatographic behavior of the metal chelates were investigated. Metal ions used were nickel, zinc, cadmium, cobalt, mercury, lead, and bismuth. The thermogravimetric analysis of these chelates showed that cobalt, nickel, zinc, and cadmium chelates can sublime (94100) % below 300 °C. Only the cobalt chelate is not extracted intoorganic solvents at all. Therefore, a gas chromatographic method for the simultaneous determination of nickel, zinc, and cadmium was investigated. Typical procedure was shown as follows. Add 1 ml of a solution containing nickel, zinc, and cadmium (more than 2 ×10^-6 mol dm^-3, respectively), 0.5 ml of a 0.5 mol dm-3 phosphate buffer solution (pH 7.5) and 1 ml of the reagent solution (7.5 × 10^-2 mol dm^-3) into a stoppered test tube and dilute to 10 ml with distilled water. Extract the chelate formed with 1 ml of chloroform with shaking for 15 min and inject 4μl of the extract into the FID gas chromatograph. Measure the peak height or the peak area. Less than 1 × 10^-4 mol dm^-3 Mg²⁺, Co²⁺, Mn²⁺, Al³⁺, Sn⁴⁺, and SiO₃^2- did not interfere. The disturbance by Fe³⁺ could be effectively eliminated by adding triethanolamine.

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A burner in which a premixed air-acetylene flame can be sandwiched with oxygen has been designed, and the atomic absorption analysis using this burner was examined. The flame temperature, the flame spectra and the analytical sensitivity were determined for samples both in aqueous solution and organic solvents. The maximum temperature of the flame of this burner was about 2900 °C. The flame spectra were different from those of air-acetylene flame and oxygen-acetylene flame. The ability for the chemical reduction in this burner was found to be higher than that of premixed air-acetylene flame. By the use of this burner, an enhancement of the analytical sensitivity was observed for those elements in aqueous solution, the monoxide dissociation energy value of which is about or above 4.5 eV. This burner was applied to atomic absorption analysis using organic sol-vents such as benzene, hexane, toluene, xylene or cyclohexane. The organic solvents were burnt satisfactorily, and the analytical sensitivities were enhanced to (220) times compared with those when aqueous solution was used. From the results, it is concluded that this new type burner is very useful for atomic-absorption work.

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The conditions for determination of calcium and magnesium using an oxygen-sandwiched air-acetylene flame by atomic absorption spectrometry were examined. The standard burner was replaced by the oxygen-sandwiched air-acetylene burner which was provided with a 0.5 mm × 100 mm slot for a premixed air acetylene flame and 1.0 mm × 110 mm two slots for an oxygen-sandwiched premixed air-acetylene flame. The conditions were as follows : Flow rate (1/min) of air, acetylene, and oxygen was 14, 3.5, and 2 respectively, and the beam height above burner top was 10 mm. The analytical sensitivity of calcium was increased about (34) times compared with a premixed air acetylene burner, and then, the interference from sulfuric and phosphoric acid was suppressed in the concentration range of 10^-5 to 10⁰ normal. The conditions for the determination of magnesium were as follows : Flow rate (1/min) of air, acetylene, and oxygen was 14, 4.5, and 5 respectively, and the beam height above burner top was 15 mm. The analytical sensitivity of magnesium was decreased about 15 % compared with premixed air-acetylene burner, but the interference from aluminium was suppressed in the concentration range of 10² to 10³ ppm. From the results described above, it is concluded that the application of the oxygen-sandwiched burner provides an attractive procedure for the determination of calcium in the sample containing sulfur and phosphorus, and for the determination of magnesium in the sample containing aluminum.

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A possibility of quantitative analysis of oxygen by X-ray fluorescence spectroscopy was studied for silicon nitride powder. An X-ray spectrometer used was composed of a sealed rhodium target tube (3 kW), an analysing crystal of thallium acid phtalate (2 d= 25.9 Å) and a gasflow proportional counter as a detector for OK_α line with an 1 μm polypropylene film window with the operating condition of X-ray tube at large current under low potential (35 kV-80 mA), intensities of the OK_α peak (2θ= 132.90 °) and those of the background (2θ= 128.00°) from the briquette samples were measured separately for 100 s and the net OK_α intensity was obtained by subtracting the background from the peak intensity. Typical counting rate of the OK_α line was 45 counts/s for the sample of 4.28 % oxygen content. A calibration curve was constructed from silicon nitride powder samples of known oxygen contents that were obtained by the graphite capsule-nitrogen fusion method using tin as a bath metal. The result showed a favorable linearity over the oxygen concentration range of (0.14.3) %. Ten kinds of samples were determined by use of the calibration curve. Analytical results agreed closely with that obtained by the fusion method, and the coefficient of variation was 2.3 % for seven samples of 3.57 % oxygen content.

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Arsenic in petroleum is known to deteriorate catalyst for refining seriously, and to cause environmental pollution. It is, therefore, important to determine arsenic in crude oils rapidly at the level of 10 ng/g. We have investigated an oxygen bomb method to decompose crude oils in order to prevent the volatilization loss of arsenic during pretreatment. After combustion in an oxygen bomb, arsenic was absorbed in magnesium nitrate-nitric acid solution and determined by graphite furnace atomic absorption spectrometry. Vanadium, sodium, iron, chlorine which commonly found in crude oils did not interfere with the measurement of arsenic, but nickel and sulfur interfered with. We found that the interference of nickel and sulfur on the arsenic absorbance could be depressed by addition of (13)g of magnesium nitrate. Furthermore the magnesium nitrate solution could be absorb not only arsenic quantitatively, but could prevent the loss of arsenic during concentration of the solution by heating. The overall recovery of arsenic was 94.3 %. Required time for analysis by the oxygen bomb method under the optimum combustion conditions was shortened about one tenth to that by dry ashing method with sulfuric acid. Arsenic content of fourteen different crude oils were determined by this method.

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Trace amount of iron(Ea) and zirconium(IV) can be determined by using their catalytic effects on the hydrogen peroxide-iodide reaction in the acidic environment. The reaction rate was followed by measuring the concentration of iodide ion by means of an iodide ionselective electrode. The most suitable concentrations of hydrogen peroxide, potassium iodide, and hydrochloric acid for the determination of iron(EU) and zirconium(IV) were found to be 0.02 M and 4 mM, 0.1 mM and 1.0 mM, 0.55 M and 4 mM, respectively. The calibration curves with good proportionality were obtained in the range of 5 to 160 μM for iron(Ea) and 1.0 to 12.0 μM for zirconium(IV).

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A computer program has been written which utilizes data of peak intensities as well as wavenumbers of unknown compounds for a search of IRDC infrared spectral data file. Matches between sample and reference spectral data are scored by using the intensity data of both spectra, and the search is executed on the TSS conversational mode. A test search using fifty observed spectra as unknown samples revealed a high performance of the present search system.

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A laser-ICP microprobe system was constructed by employing a low-energy Nd:YAG laser (max. 0.1 J per pulse) and a commercial laser optical system. The amounts of metals vaporized by a laser pulse, which were measured directly by weighing samples before and after the laser irradiation, ranged from less than 0.01 μg for gold and silver to 130 μg for lead. The length and diameter of a vaporcarrying tube between the sample chamber and the ICP torch affected not only emission signal responses but also reproducibility of intensities. Linear working curves were obtained for chromium, manganese and nickel in low-alloy steels. The detection limits were 0.017, 0.074 and 0.025 % for the single-pulse mode and 0.004, 0.047 and 0.004 % for the multi-pulse mode, respectively.

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