A correlation between the integrated spectral line intensities of an element to be determined and that of matrix iron was investigated. The correlation was related to physical and chemical characteristics of elements. Two kinds of samples containing each element of 50 to 400 ppm were used and each sample consisted of four pieces. A vacuum spectrometer with a low voltage spark source under argon atmosphere was used. Excitations and measurements were repeated four times on each piece of the sample, and then, for each element, the relative change of integrated intensities was calculated. For each kind of the samples, the correlation coefficients and the square roots of dispersion ratio between the ratios of relative changes were calculated. For manganese, nickel, chromium, molybdenum, niobium, selenium and cobalt, the correlations were found to be highly significant. For almost all of these elements, their spectral lines are ionic and as in the case of iron, and the excitation energies of these spectral lines are close to that of iron. For the other elements, the correlations were not so significant. Because of the segregation of elements, the correlation practically was not apparent for silicon, sulfur, aluminum, titanium and zirconium.

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Meclofenoxate hydrochloride (Mc) is easily hydrolyzed to p-chlorophenoxyacetic acid (PAA), so that a rapid and selective method is required for quantitative determination of PAA in Mc preparations. In this paper, a high-speed liquid chromatographic method of Mc and PAA analysis is established. PAA was separated from Mc on a column packed with Hitachi-gel 3011 (styrene-divinylbenzene copolymer) by elution with acetonitrile-28% ammonia water mixture (99.9:0.1) (method I), and on a Hitachi-gel 3011-O (hydroxymethylated styrene-divinylbenzene copolymer) by elution with acetonitrile-acetic acid (99:1) mixture (method II). Chlorpheniramine maleate was used as an internal standard for method I, and protizic acid was used for method II. They were detected by UV absorption at 280 nm. Quantitative analysis of Mc is performed in both method I and method II, but for the determination of PAA method II is preferred. These methods are rapid, selective and sensitive for the analysis of Mc preparations. The authors also studied a stability of Mc in several solvents and found that Mc rapidly degenerates in methanol solution and that the degradation product in methanol was different from PAA which is the degradation product of Mc in water. This unknown product was isolated and identified as methylester of PAA by IR and NMR spectra.

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Sediment sample (1 g) was treated with Chester and Hughes's method (1967). Cadmium in sediments was leached into a mixed solution of 1 M hydroxylamine hydrochloride and 25% (v/v) acetic acid. The residue was then dissolved in nitric acid and, after drying up, diluted to 100 ml with 0.01 M HCl solution. Various coexisting elements in the solutions thus obtained interfered with the determination of cadmium by atomic absorption spectrophotometry with a carbon tube atomizer. Among the elements tested i. e., Na, K, Mg, Ca, Fe, Al, Si, Mn, Zn and Cu, 200 ppm of magnesium, 200 ppm of iron and 8 ppm of zinc in the solution decreased the absorbance of cadmium by 44%, 28% and 20%, respectively. Mock solutions containing 10 ppb of cadmium and 10 foreign ions as chloride were treated in a similar way, and both calibration and standard addition methods were tested. Because of interference of coexistidg elements, the calibration method is not recommened. The standard addition method should be used after diluting the solution to one tenth. With this method cadmium concentrations in the sediments of the Hiro Bay in Hiroshima ranged (0.562.36) ppm. The relative standard deviation for a sample containing 1.0 ppb of cadmium was 4.0%.

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This report deals with the investigation of a simple determination of water in organic solvents by using alumina and silicagel whose surface is hydrophobicated by alkoxylation, such as esterification, with alcohols. Alumina hydrate (Baemite) or dried silicagel was treated by dipping for a few hours in carbon tetra chloride solution of lauryl alcohol in the presence of phosphorus pentaoxide. Then, we removed the solution and washed with organic solvents, and dried in vacuum desiccator at room temperature. This modified material was packed in a glass tube (φ = 4 mm) and dipped into a sample solvent. The sample was inhaled with constant rate from the head of the tube, and we measured the osmosis height of solution after a given time. The observed height was compared with a calibration curve which is prepared by organic solvents involving known constants of water. An oil soluble dye was dissolved in an organic solvent in order to make the measurement of the heights easy. The observed results agreed with results by Karl Fisher method.

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An analytical method for determination of total nitrogen (TN) and total organic carbon (TOC) in water was investigated. Nitrogen compounds and carbon compounds were converted into nitrogen and carbon dioxide, respectively, in a stream of carrier gas (helium) by injecting a sample with a microsyringe into a reaction tube which was packed with alumina coated with palladium (0.3%). After removal of steam, oxygen and hydrogen from the gas stream, nitrogen and carbon dioxide were analyzed with a gas chromatograph, and TN and total carbon (TC) were determined. Inorganic carbon (IC: carbonate or bicarbonate) in water was converted into carbon dioxide by injecting a sample into a reaction tube which was packed with ion exchange resin containing sulfonic group and analyzed with a gas chromatograph after removal of steam. TOC was determined from the difference between TC and IC. The detection limits of TN and TC were about 0.5 mg/l using a sample size of 20μl and that of TN about 0.1 mg/l using a sample size of 80 μl The coefficients of variation were several % in case of concentration above 10 mg/l and about 10% in case of concentration under 10 mg/l. The observation time was about several minutes and analysis was made using peak height of chromatogram. The results of TN by this method were agreed with those by the Kjeldahl method.

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The effects of organic solvents on the high-frequency (H. F.) polarograms using cadmium-potassium chloride electrolytic system has been investigated. Yanagimoto polarograph Model PF-501 was used. The well defined polarograms were obtained in the 14 wtaer-organic solvent systems and a series of change of polarogram was obtained by varying the organic solvents. According to the potency of rectification effect of the solvents, the following sequency was obtained: ammonia, pyridine, formamide, acetamide, N-methylformamide, DMSO, acetic acid, DMF, acetonitrile, ethanol, and acetone. Ammonia and pyridine increase the positive rectification effect. The solvents from formamide to DMSO in the above series give equal positive and negative rectification effects. The solvents from acetic acid to acetone increase the negative rectification effect. The type of increasing positive rectification effect has stronger basicity than water and less than 20 of dielectric constant, and the type of equal positive and negative rectification effect is a little basic and amphiprotic protophilic solvent. The type which enhances nega-tive rectification effect has 2040 of dielectric constant. But acetic acid is an exception.

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An automatic instrument for simultaneous determination of total nitrogen (TN) and total organic carbon (TOG) in waste water was developed. The analytical method adopted was based on the combustion-gas chromatography reported in the previous paper. An acid-treated sample was introduced into a deaeration tube shown in Fig. 2 with a peristatic pump, where dissolved nitrogen and inorganic carbon were removed by extracting into the carrier gas. The deaerated sample was continuously injected into a combustion tube, pollutants in the sample being combusted perfectly. After removal of steam from the combustion gas stream, a portion of the gas was periodically introduced into the reaction tube packed with copper tips. Finally, nitrogen (N₂) and carbon dioxide were analyzed with a gas chromatograph. The removal efficiency of dissolved nitrogen and carbon dioxide from acid-treated sample were found to be higher than 90% and 86%, respectively. The detection limits were 0.6 ppm for total nitrogen and 0.2 ppm for total organic carbon. Coefficients of variance were within 1% for 50 ppm of total nitrogen and total organic carbon. The 95% response time of the system was about 10 min. Applying the apparatus to the analysis of the water treated by activated sludge, it was shown that the instrument developed in this study was useful for monitoring of total nitrogen and total organic carbon in waste and treated water.

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Copper at the sub ppm level in milligram samples of high purity tantalum metal powder was determined by tungusten filament vaporization-microwave plasma emission spectrometry after removal of tantalum by cation exchange resin. A 10-mg sample was dissolved in 50μl of 14 M hydrofluoric acid and 20 μl of 7 M nitric acid in a 500-μl Teflon beaker, and the solution was diluted to 500 μl with water. The solution was introduced onto a cation exchange column (Bio-Rad AG 50 W-X12, (100200) mesh, 2 mmφ×35 mm, polyethylene tubing). The column was washed with 300 μl of wash solution (1.4 M HF +0.28 M HNO₃) followed by 400 μl of water to remove tantalum. The adsorbed copper was eluted with 200 μl of 6 M hydrochloric acid. The effluent was evaporated to dryness in a 200-μl Teflon beaker and the residue was dissolved in 10 μl of 0.005 M potassium chloride-0.05 M hydrochloric acid. A 2 μl aliquot was placed on a tungsten filament, dried, vaporized by pulse heating using a high-capacity condenser (220000 μF) and carried into an atmospheric pressure argon plasma (2450 MHz, 70 W). The lower limit of determination was 0.05 ppm and the precision was about 15% at the 0.2 ppm level. A single determination took 2 to 3 h.

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A Schiff base, 3-N-salicylideneamino-4-hydroxybenzenesulfonic acid (SAPS) which is derived from salicylaldehyde and 2-aminophenol-4-sulfonic acid, was synthesized and tested for the spectrophotometric determination of copper (II) in aqueous solution. The complex has an absorption maximum at 406 nm and a maximum absorbance is obtained in the pH range from 4 to 7. The procedure is as follows: Transfer the sample solution containing up to 100 μg of copper to a 25 ml volumetric flask. Add 5 ml of acetate buffer (pH 5.2) and 2 ml of 0.1% SPAS solution. Dilute to the mark with water and measure the absorbance at 406 nm using the reagent blank as a reference. Beer's law is obeyed over the range 0100 μg of copper (II). The apparent molar absorption coefficient of the complex is 1.45×10⁴ l mol^-1 cm^-1, and Sandell's sensitivity of the complex is 4.4×10^-3 μg cm^-2. Iron (III), aluminum, molybdenum (VI) and vanadium (V) interfere. The proposed method is rapid and simple, and applicable to the analysis of steel for copper. Interference from iron (III) can be avoided by MIBK-amylacetate (1+1) extraction in 7 N hydrochloric acid solution. Copper {(0.10.5) %} in iron and steel standard samples can be determined in this way.

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The dielectric constant detector for high speed liquid chromatography has been constructed and investigated of its practical utility. Experiments have been performed with a GPC column by using THF as a mobile phase or with an ODS-silica column by using methanol or methanol/water (9/1) as a mobile phase. The volume of detection cell is 5 μl and band spreading in the detection cell is less than 30 μl. The temperature of a detection cell has been controlled with a cooling semiconductor thermocouple and its stability is about ±0.01°C. In this condition a lower limit of detection is about 2.7×10^-5(dielectric constant unit). Practical utility of this detector has been investigated with polymer samples and bile acids. The responses of this detector for these samples are compared with that of a conventional refractive-index detector. This detector has a high sensitivity for these samples and is much more useful than the conventional one in the case of these samples.

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A new cellulose ion exchanger was synthesized and its properties were investigated. A carboxycellulose (C-cell) was esterified with a mixture of ethanol and acetyl chloride. The esterified C-cell was converted to aminoethylcarbamoylcellulose (E-cell) by letting an ethanolic ethylenediamine react with it. The Ecell was mixed with a mixture of pyridine, carbon disulfide and ethanol, and allowed to stand while being stirred for 7 days at 20°C. The products were washed with methanol and dried. From the results of nitrogen and sulfur analysis, absorption spectra and behavior of mercury for collection, it seems that the products contain 5-(2-N-dithiocarboxyaminoethyl) carbamoylcellulose (D-cell). The effects of pH, collecting time and co-existed chloride and other metal ions on the collection of mercury were investigated with 0.1 g of the D-cell for 50 ml of solution (Hg, 2 ppm). The uptake of mercury on the D-cell was constant between pH 1 and 5, and mercury could be collected quantitatively. In the presence of chloride ion(1 M), no influence was observed. At pH 1, Mn (II), Co (II), Ni (II), Zn, Cd and Pb (II) were not collected on the D-cell. The D-cell can be applied satisfactorily for the preconcentration and separation of mercury.

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Full automatic analytical system of X-ray fluorescence spectrometer for research laboratory, consisting of X-ray fluorescence spectrometer, automatic sample loader and data processing system, was developed. The X-ray fluorescence spectrometer includes microcomputer which sets various conditions automatically for 500 measurements. The automatic sample loader was newly designed to feed sequentially each 5 of 21 kinds of samples. The data processing system consists of minicomputer with 12K words, teletypewriter, papertape puncher and papertape reader. In the case of routine quantitative analysis, many kind of samples could be analyzed continuously by only pushing start button. On the other hand, a qualitative analysis was performed by off-line operation of the data processing and of the retrieval for the identification. The data from the spectrometer were punched out on paper tapes, and then were fed to the computer (FACOM 230-28). The computer program for qualitative analysis consists of several subprograms, namely, counting loss correction, smoothing, peak searching, background subtraction, conversion to angle (2θ) and intensity (cps), and identification program. Angles, intensities, identified elements, overlapping elements and the reliability of identification were printed out on the line printer. The X-ray fluorescence spectrum was also printed out on the X-Y plotter. The detection limit of the peak intensity was about 5 times as much as statistical variation of the background intensity.

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The method for determination of aluminum using an oxygen sandwiched air-acetylene flame by atomic absorption spectrophotometry was examined. The sensitivity of aluminum was about 30μg/ml/1% at an air flow rate, 13 l/min, acetylene flow rate, 5 l/ min, and oxygen flow rate, 8 l/min. The presence of ammonium acetate enhanced the sensitivity up to 10 μg/ml/1%. The enhancement was also observed by the addition of hexamethylenetetramine, urea, ammonium chloride, ammonium perchlorate, ammonium fluoride and hydrofluoricacid. The sensitivity of aluminum was (1.65.5) times greater than that in the absence of these reagents. The oxygen sandwiched flame is more costless than the nitrous oxideacetylene flame. Applying to the determination of aluminum in aluminum bronze and zinc die cast, satisfactory results were obtained.

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Improvements were made with regard to the precision in determination of microgram amounts of zinc in aluminum by the solvent extraction-atomic absorption spectrophotometry. Authors examined several causes for lowering the precision, which were due to zinc contamination by its desorption from the inner wall of separating funnels, dissolution of beaker or dehydrating materials, and impurities in reagents used. The major cause was contamination from zinc adsorbed on separating funnels. It could not be removed completely by the brush cleaning with sodium bicarbonate and liquid soaps, by shaking with tri-n-octylamine methyl isobutyl ketone solution (2 v/v%) for 5 min or by immersing in nitric acid (1 + 1) for 24 h. The complete decontamination was possible only by the ultrasonic washing (50 kHz and 35 W) for 10 min in hydrochloric acid (1 + 1) or nitric acid (1 + 1). Since rinsing with tapping water causes zinc contamination, it is necessary torinse with distilled water; the main reason for zinc contamination is consideredto be the use of tapping water. Other measures to eliminate the contamination inanalysis of aluminum were to dissolve samples in beakers of quartz or polyethylene, but not borosilicate glass, to dehydrate with dry filterpaper washed with 5 ml of methyl isobutyl ketone and to use reagents selected so as to be lower in zinc impurities. These results will be very useful for the determination of microgram amounts of zinc by using solvent extraction methods in the field of environmental pollution

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The fluorometric method using the aqueous sodium hydroxide solution as the trapping solution possesses a sufficient sensitivity to determine hydrogen sulfide of background levels in the atmosphere. But the sulfide ion collected in the trapping solution is unstable, so the samples must be analyzed soon after sampling. The authors modified the trapping solution by adding a small amount of EDTA for better stability of the sulfide ion in the solution. The EDTA added into the solution masks the metallic ions such as ferrous, ferric and manganse ions, and it lowers the rate of oxidation of sulfide ion as a result of decrease of these ions in the solution which are considered to work as catalysts of oxidation. In case of 1.0×10^-5 M of sodium sulfide in 0.1 N NaOH, the concentration decreased at a rate of about 20% in a day at room temperature, but it became more stable by the presence of 0.01 M EDTA and the sulfide solution was stable at least for one week if the solution was kept in a dark room. The sulfide solution containing EDTA was also quite stable to aeration; 5×10^-6 M of sodium sulfide in 0.1 N NaOH in the presence of 0.01 M EDTA was stable even after passing air through the solution at a flow rate of 0.5 1/min for 2 hours. The modified trapping solution containing EDTA enables the fluorometric method to be more practical in the determination of hydrogen sulfide of background levels in the atmosphere.

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Hydrophobic gel particles containing trioctylmethyl-ammonium chloride (TOMA-Cl) were prepared by the gelation of TOMA-Cl in chlorobenzene solution using dibenzylidene-D-sorbitol as a gelation agent. A gel column of 9.0 cm³ held 5.2 cm³ of stationary phase containing (0.755.68) ×10^-5 mol of TOMA-Cl. This type of column containing 0.75×10^-5 mol of TOMA-Cl quantitatively extracted ferricyanide ion from aqueous solution in a mole ratio of TOMA-ferricyanide as 3: 1. Similar type of column holding 5.68×10^-5 mol of TOMA-Cl gel particles extracted more than 2 mg of ferricyanide ion, although the extraction was less quantitative. The selectivity of TOMA-Cl to ferricyanide ion was investigated by carrying out the column extraction process using the samples containing other anions in high concentration. The order of the selectivity was found to be Fe (CN)₆^3->>NO^3->Br^->Cl^->>SO₄^2-. TOMA-Cl gel column is recommended for separating and enriching ferricyanide ion in a very dilute solution. The main advantage of this method is that any kind of mixture between the extraction reagent and the solvent can be gelated to make a gel column for the separation of specific ions.

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