The specific retention volume (V_g) of 54 halocarbons containing F, Cl, Br, and I (i. e., C_nF_2n+2-x-y-zCl_xBr_yl_z where n = 15) was measured by using a gas chromatograph with a Silicone DC 550 column, and the correlations of the log V_g with various physicochemical parameters were investigated. (a) The log V_g was found to correlate linearly with the composition of the halogen atoms in the molecule: the additivity in log V_g can be represented by an equation with respect to the numbers of F, Cl, Br, and I in the molecule. The relationship was shown in a three-dimensional diagram in which log V_g value was expressed as the height from the ground plane; the correlation diagram appears to be of special analytical importance. (b) The relationship between the log V_g and the number of carbon atoms in the halocarbon molecule was investigated. (c) The log V_g was correlated linearly with the volume of molecule which was estimated by assuming that the molecule was composed of spheres with the van der Waals radii corresponding to halogen atoms. (d) The correlation of the log V_g with the boiling point or with the molar refractivity was also examined, where the halocarbons containing iodine atoms deviated systematically from the linear correlation.

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A Nippon Jarrell-Ash model AA-1 atomic absorption/flame emission spectrophotometer was used, fitted with a HETCO total consumption burner for air-hydrogen flame.
The effects of acids and their ammonium salts on europium were studied. Perchloric acid of (0.0050.01) M increased the europium absorption by 3.7 times and 0.01 M ammonium perchlorate increased the absorption by 4.4 times.
It was found that the cadmium decreased the europium absorption by 40% in the concentration of 8000 ppm in an aqueous solution. Therefore a method for eliminating the interference of cadmium was studied by the addition of ammonium perchlorate which enhances the europium absorption. In the case of ammonium perchlorate solution below 0.5 M, the europium absorption gradually decreased with increasing cadmium concentration. But in the case of 1.0 M, the absorption did not change. The interferences of various cations on europium were also eliminated or decreased by the same procedure. The quantitative analysis of europium in the presence of cadmium was made by atomic absorption spectrophotometry in an air-hydrogen flame, provided that the ammonium perchlorate was added in the sample and standard solutions of europium in equal concentration. The estimated values obtained by proposed method was in fair agreement with the values obtained by spectrophotometric method.

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Cadmium forms insoluble mixed ligand complex with ο-phenanthroline and iodide ions. By using the complex a new gravimetric method for the determination of cadmium was investigated.
The recommended analytical procedure is as follows: Adjust pH value of a solution containing 5 to 45 mg cadmium to 4 with 3 M acetic acid-sodium acetate buffer solution. Add over threefold moles of potassium iodide to the solution and heat to just before boiling. To the solution add 0.1% ascorbic acid solution and then 0.1 M ο-phenanthroline solution drop by drop in excess with stirring, and cool the mixture to room temperature. Filter the precipitates and wash first with 0.01% potassium iodide solution and then with water. Dry the precipitates at 110°C for two hours and weigh as Cd(ο-phen)₂I₂ (I). The gravimetric factor of the complex for cadmium is 0.1547.
Composition of the complex formed changes with the amounts of ο-phenanthroline added. When ο-phenanthroline is added less than equal moles to cadmium, the complex precipitates as Cd(ο-phen) I₂ (II), but in case of adding one to twofold moles of the reagent, mixture of (I) and (II) precipitates. In those cases there is a tendency that negative errors occurred in determination of cadmium. However, by adding the ο-phenanthroline solution 2.4-fold moles against cadmium, the ternary complex (I) precipitates quantitatively (Table 2 and Fig.3).
As a large excess of potassium iodide is present against cadmium in the solution, there is a tendency that iodide ions are oxidized to iodine by air and the precipitates are contaminated with the iodine. The contamination, however, can be avoided when precipitates are formed from the high temperature solution in the presence of ascorbic acid.
The effect of diverse ions on the determination of cadmium has also been studied (Table 5). By the presented procedure 5 to 45 mg of cadmium are determined with a standard deviation of <0.05 mg (Table 4). It was also checked thermoanalyticaly that the ternary complex is stable up to 280°C.

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A data processing system of off-line mini-computer for low-resolution fast scanning mass spectrometer is discussed. This system consists of a four channel analog data recorder, a mini-computer with 4 K core memories and 8 K drum memories, an A/D converter of 8 bit, a teletypewriter and an XY plotter.
The analog data recorder simultaneously records mass peak signals, mass marker signals and drive power voltage for a mass recorder during scanning.
Processing of the tape consists of reading of a internal analog to digital converter of the computer at a rate of 200 μs sampling interval.
The mass marker signals on the tape are converted to 5 V pulses by a interface and put into the computer through I/O box of it. When the pulses are received, the computer searches the maximum peak appeared in before and behind of 50% of the corresponding pulse, and decides the mass number correspond to the mass marker. As the drive power voltage of the mass recorder drops at the end of mass scanning, the dropping voltage signal on the tape is converted to a 5 V pulse signal by the interface and put into the computer through I/O box.
By detecting the pulse signal, the computer understands the end of the mass scanning and stops the data recorder. The computer begins to calculate pattern coefficients of mass spectrum from memorized data, then tabulates the pattern coefficients and draw a bar-graph of it on the XY plotter. Peak signals are memorized in two levels, that is, the one is the high level of peak signal and the other the low level signal. When the high level peak signal on the tape has overflowed, the computer stops and rewinds the data recorder and replayed by changing in the low level channel. The relationship of rewind time of the data recorder and the tape length is discussed. The pattern coefficients are tabulated in two dimension of mass number for the convenience of looking for.

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In the presence of cyanide ion, copper (II) ion is quantitatively reduced to stable cyano complexes of copper (I) in aqueous solution. If ο-cresolphthalin is present in the solution, it is oxidized to ο-cresolphthalein, and the color turns purplish red in alkaline solution. This color change has been used by Nicholson to determine hydrocyanic acid in cyanogenetic plants. However, the conditions necessary for stability and reproducibility of the color have not been established. Therefore, the optimum conditions for the operation at each stage of the procedure were investigated, and the following procedure was established.
A neutral sample solution containing 05μg of cyanide ion is taken in a 25 ml volumetric flask, and 1 ml of 0.2 per cent ο-cresolphthalin in 0.1 N sodium hydroxide solution, 1 ml of ethanol and 1 ml of 0.039 per cent copper (II) sulfate pentahydrate solution are added. It is made up to the mark with water, and allowed to stand at 30°C for 30 minutes. The absorbance of the colored solution is measured at 568 nm with a 1-cm cell against the reagent blank.
The apparent molar extinction coefficient based on cyanide ion is about 6.5×10⁴ l/mol cm, and the sensitivity of this method is inferior to the pyridinepyrazolone method, i.e., 90 per cent of the latter. This procedure is applied easily for the determination of cyanide ion in the samples free from interfering ions such as Co²⁺, Ni²⁺ which form complexes with cyanide ion.

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Lanthanide shift reagent, Eu(DPM)₃, has been used for the analysis of the isomeric mixtures (1, 3-, 1, 2- and 2, 3-butanediol) by taking advantage of the dif ferences in the chemical shift gradients of the methyl protons with proton NMR at 60 MHz.
The chemical shift gradients of the methyl protons for 1, 3-, 1, 2-, and meso-form and dl-form of 2, 3- butanediol were 6.40, 5.63, 12.6 and 10.9, respectively.
The resonances for the methyl protons were in the envelope centered 1.2 ppm in the spectrum for a CDCl₃ solution of the isomeric mixture. However, by addition of 0.84 mole of Eu(DPM)₃ per mole of butanediol isomeric mixture, the methyl protons for each of the components gave a resolved resonance in order of 1, 2-, 1, 3-, and dl-form and meso-form of 2, 3-butanediol from high field as predicted by the chemical shift gradients. By using the calibration curves, it was possible to determine the proportion of isomers by the peak areas of methyl protons with errors of about 2%.

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Both ethanol solutions and evaporated thin films of mixed crystals containing pure anthracene in pure phenanthrene were prepared in various mole concentrations. By measuring fluorescence spectra and life times of these samples, the limit of determination for anthracene in phenanthrene was quantitatively investigated. The method of fluorescence spectra: the relative intensity ratios of fluorescence spectra changed depending on the concentrations of anthracene in these samples. In the case of ethanol solutions, the concentration could be quantitatively measured to 10^-6 mol/mol by using relative intensity ratios of the 423 nm-peak to the 366 nm-peak. In the case of evaporated thin films, the concentration could be quantitatively measured to 10^-8 mol/mol by using the ratios of the 410 nm-peak to the 370 nm-peak. The method of fluorescence life times : the fluorescence life times changed with the concentrations of anthracene in the samples. The average life time of fluorescnece of pure phenanthrene was 69.6 ns {in the region of (360440) nm}. The average life time of pure anthracene was 19.9 ns {in the region of (380500) nm}. The average life times of mixed crystals were as follows; 10^-3mol/mol20.5ns, 10^-5mol/mol42.8ns, 10^-7 mol/mol53.4 ns, 10^-9 mol/mol59.6ns. Therefore, the lower limit of determination for anthracene in phenanthrene was decreased to less than 10^-9 mol/mol. Furthermore, it was found that the fluorescence life times of phenanthrene reported in literatures were largely effected by impurities, comparing with the life times presented in this report.

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A simple and selective spectrophotometry for nickel was developed by dissolving 1-(2-thiazolylazo) 2-naphthol (TAN) and its nickel chelate in water with Triton X-100. The absorbance of the chelate at 595nm is constant in the pH range (4.710). For full color development it requires 20 minutes at pH 7.1, and 5 minutes at pH 9.2. The absorbance of a reagent blank at 595 nm is low (<0.030) below pH 7.0. On the addition of N-(dithiocarboxy)-glycine (DTCG) after the color development, the chelate decomposed at pH <6.2. DTCG, pyrophosphate and tartrate were found to be an excellent masking reagent for foreign ions except iron (II), so that any iron in the sample must be tervalent. The analytical procedure is as follows: place the solution containing less than 110 μg of nickel in a 50-ml volumetric flask; add 2 ml of 0.5 M sodium potassium tartrate, 1 ml of 0.5 M potassium pyrophosphate, 0.5 ml of 1 M ammonia buffer (pH 9.2), 20 mg of DTCG and then 2 ml of TAN solution (TAN 0.1 g: Triton X-100 20g: water 80g); stand for 10 minutes and adjust the pH to (6.47.0) with 1 M ammonium citrate (pH 6.0); dilute to the mark with water and measure the absorbance at 595 nm against the reagent blank. Beer's law is obeyed over the range {(11110) μg Ni/50 ml} and the ε value is 4.0×10⁴. The precision (95% confidence) is± 0.5 μg for 57.0 μg of nickel. The method can successfully be applied to the determination of nickel in soils.

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A simple and rapid method was proposed for the determination of microgram quantities of lead (II), iron (III), copper (II), zinc (II), manganese (II), cadmium (II), chromium, antimony (III), and arsenic (III) in water.
A water sample containing the above elements {(150)μg} except arsenic (III) was transferred to a glass-stoppered test tube, the pH was adjusted to 5.05.5 with an acetate buffer, the solution being diluted to 50 ml, and 5 ml of 2% sodium diethyldithiocarbamate (DDTC) solution was added. After 5 minutes, 1 ml of 1.7 w/v % dimethylsulfoxide solution of dibenzylidene-D-sorbitol was added, and the solution was shaken several times to coagulate the DDTC chelate. The precipitates were collected on a Toyo No. 5 A filter paper, dried, and delivered to X-ray fluorescence analysis. For arsenic (III), ammonium pyrrolidinedithiocarbamate was used instead of DDTC. All the elements investigated were quantitatively collected.
The determination of the valence states of chromium (III and VI) was not successful in spite of the difference in the reaction rate with DDTC at room temperature. Total chromium can be determined by heating for 5 minutes in boiling water to convert the aquo complex of chromium (III) to the DDTC complex.
The analytical results for samples of industrial waste water and river water by the proposed method were in good agreement with those obtained by the atomic absorption method.

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The analyzer is composed of a sample changer, reagent addition devices, a distillation vessel, a color reaction vessel, a spectrophotometer, a controller, etc. The automatic procedure is performed according to the predetermined distillation and color reaction programs after dissolving 0.5 g of steel sample in aqua regia and fuming with sulfuric acid-phosphoric acid. The sample solution on the sample changer is transferred into the distillation vessel, where boron is distilled with methyl alcohol by heating and aeration. The distillate is collected in the distillate vessel, and a 1/2 aliquot is transferred into the color reaction vessel with small amounts of water. After the addition of glacial acetic acid and propionic anhydride, the distillate is circulated through the circulating pipe which is composed of an air blowing tube, a bubble remover, a flow cell and a drain valve. Oxalyl chloride (to eliminate water), sulfuric acid, the curcumin reagent (to form the boron complex) and an acetate buffer are added, and the absorbance of the solution is measured at 545 nm. The analytical results of steel samples were in good agreement with those obtained by the conventional method and with certified values.

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The optimum conditions of ammonia distillation for the nitrogen determination in steel have been studied using the automatic apparatus based upon the distillation by heating and aeration after the addition of a sodium hydroxide solution. The distillate volume, which was important to improve the sensitivity of the determiantion, was decreased with increasing solution volume, decreasing hydrochloric acid content, and decreasing heating power. The initiation time of ammonia distillation, which was efficient for the rapid distillation, and the ammonia recovery were improved by decreasing the solution volume and increasing the heating power. The optimum conditions obtained from the experiments were as follows: sample solution 25.00 ml, washings 12.20 ml, sodium hydroxide solution (40%) 19.80 ml, heating power 150 watts, heating period 170 seconds and aeration rate 200 ml/min. Ammonia is quantitatively recovered with 6.5 ml of distillate in 170 seconds.

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The effect of polar organic solvents such as methanol, ethanol, 1-propanol, 2-propanol and dioxane on the spectrophotometric determination of copper with Chromazurol S (CAS) were investigated. Excess CAS with copper in the mixtures of the solvent and water form predominantly the 1 : 2 complexes with the absorption maxima at (590610) nm. The bathochromic shifts are observed in the absorption spectra of the complexes by adding the solvents. The molar absorptivities increase from 2.2× 10⁴ observed in the aqueous solution to (3.86.3)×10⁴ in the mixtures of the 80 v/v solvent and water. The molar absorptivities tend to increase with the decrease in the values of the dielectric constants of the solvents. The relationship between the absorbances and the concentrations of copper {(0.52.6)×10^-5M} is almost linear in the 80 v/v solvent-water systems containing 3.4×10^-4M CAS and 0.01 M hexamine.

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In order to determine fluorine in organic compounds, the authors attempted the indirect determination of fluorine by decomposing fluorine-containing derivatives with sodium biphenyl, followed by atomic absorption spectrometry of iron in MIBK phase. The recommended procedure is as follows: The aqueous solution seperated after the decomposition with sodium biphenyl, was adjusted its pH at 3.0 with 0.2 N hydrochloric acid. To 5 ml of this solution, was added one ml of an excess of a ferric chloride solution which contains 10 μg/ml of Fe and then one ml of 2.5% ammonium thiocyanate solution. Excess iron was extracted with 2 ml of MIBK as ferric thiocyanate and the iron content extracted was measured by atomic absorption spectrometry. Fluorine is determined indirectly by this method and the calibration curve was linear in the range of (0.56.0) μg/ml. Metals which form more stable fluorine complexes than Fe (III) interfer, but the anions except CN^- does not disturb the measurement.

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Tungsten (VI) forms a blue complex with Bromopyrogallol Red (BPR) in the presence of excess zephiramine in an acidic solution containing hydrochloric acid. The absorption maximum of the tungsten-BPR-zephiramine complex was observed at around 621 nm, and the absorbance was strongest in (1.01.3) N hydrochloric acid solution. The calibration curve showed that Beer's law held over the range (235)μg tungsten (VI) /25 ml. The coefficient of variation of the absorbance for 30μg of tungsten (VI) was 0.4%. The molar absorptivity was 6.5×10⁴ at 621 nm. The molar ratio of tungsten to BPR in the complex was estimated to be 1 : 1 by the continuous variation method. The sensitivity of this method is superior to that reported by Dhupar, et al. using BPR.
The analytical procedure was as follows. A sample solution containing (235) μg tungsten (VI) is taken into a 25 ml measuring flask. Suitable amount of 3 N hydrochloric acid, 2.0 ml of 2 w/v% gum arabic, 2.0 ml of 10^-2M zephiramine and 1.0 ml of 0.03 w/v% BPR are added to the flask, and the solution is made up to 25 ml with water, the final acidity being (1.01.3) N. The mixed solution is heated in a water bath of (55±2) °C for 10 minutes. After cooling for 20 minutes, the absorbance of the colored solution is measured at 621 nm against the reagent blank. Mercury (II), bismuth (III), antimony (III), tin (IV), vanadium (V), chromium (VI), molybdenum (VI) and nitrite interfered with the determination even in the same amount as the tungsten (VI). The permissible amount of chromium (VI) could be increased by addition of 1 w/v% L-ascorbic acid and 0.1 M EDTA.

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The use of thymol solution in place of 2, 4-xylenol in the determination of nitrate nitrogen increases threefold in sensitivity and simplifies the analytical procedure because heating procedure is not necessary. Interference from nitrite nitrogen is removed with sulfanilic acid. The proposed analytical procedure for nitrate nitrogen using thymol is as follows.
Take a sample solution of 5 ml {containing (110) μg NO₃-N} and 0.5 ml of 1% sulfanilic acid solution in a 100 ml separatory funnel and mix well. Add 15 ml of 85% sulfuric acid and 0.5 ml of thymol solution. After standing for 5 minutes at room temperature, dilute to about 70 ml with water. Mix well and stand for 20 ml. Extract nitrate nitrogen after shaking for 2 min with 10 ml of n-butyl acetate and (23) drops of 0.1% pentamethoxyred solution. After discarding the aquous layer, add 10 ml of 1 M NaOH solution in n-butyl acetate, and shake for 2 min. Filter the NaOH solution through a dry filter paper and measure the absorbance at 395 nm against reagent blank obtained by the same procedure. The molar extinction coefficient is 6.2×10³.

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A method was presented for the determination of antimony in pig lead. The method consisted of the evolution of stibine, its fixing on a chloroauric acid. test paper, and the measurement by X-ray fluorescence spectrometry.
Procedure: Transfer a sample solution containing up to 200μg of antimony into an evolution vessel (200-ml Erlenmeyer flask). Add 15 ml of 12 M hydrochloric acid, and dilute the mixture to 50 ml with water. Add 5 g of granular zinc, and immediately connect a capture vessel to which a test paper has been attached. After standing for an hour, remove the test paper, set it on a sample holder, and count the X-ray fluorescence intensity of the SbK_α line (2θ=13.47°) in a vacuum using a tungsten target X-ray tube (50 kV-20 mA) and a LiF crystal.
The intensity of the X-ray fluorescence was almost proportional to the antimony amount (up to 200 μg). The standard deviation was 2.6% (with 100 μg of antimony) in five runs.

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