A simple and rapid detection method of inorganic anions was investigated by using aluminum (III)-morin fluorescent complex.
Thirty kinds of inorganic anions developed on paper and cellulose thin-layer and located under UV 365 nm after spraying with this complex. Among these anions, twenty five ions such as halogen, halogenooxyacids, sulfur containing anions, cyanoferrates. chromates, nitrile, nitrate, phosphate, tungstate, molybdate and vanadates showed the fluorescence quenching on chromatograms.
The remaining anions (arsenite, selenite and selenate) did not show the remarkable quenching effect.
From the experimental result, fluorescence quenching effect of anions was classified into three grades: strong (violet color : iod- and bromoxyacids, sulfite, sulfate, cyanoferrates, chromates, nitrite, nitrate, phosphate), medium (blue color : halogen, sulfide, vanadates) and weak (yellow color : chlorooxyacids, thiocyanate, tungstate).
The mechanism of fluorescence quenching caused by these inorganic anions might involve a chemical reaction which convert aluminum-morin fluorescent complex into aluminum salts with no fluorescence ability.
When a basic solvent system containing 28% ammonium hydroxide-acetone-n-butanol (60:130:30) was used, a rather clear relationship among R_f values, electronegativities and ionic radii of halogen was observed. Namely, the R_f values became higher as the electronegativity of halogen decreased or the ionic radius increased.

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The coprecipitation of copper and cadmium 8-hydroxyquinolates from homogeneous solution was conducted from the viewpoint of crystal and analytical chemistry. To the mixed solution containing copper and cadmium ions an 8-acetoxyquinoline solution was added by keeping the pH of the solution at 9 and the resulted solution was stirred at 25°C. The precipitate formed at each stage of the reaction was analyzed. The precipitates in an initial stage were composed of needle crystals which characterizes copper 8-hydroxyquinolate, and were associated with a slight amount of cadmium. The first half of the coprecipitation curve for the needle crystal formation resembles the logarithmic distribution curve of λ equal to about 0.01. The precipitation of most of the copper ions was followed by the precipitation of cadmium 8-hydroxyquinolate crystal in the plate form. The needle crystals of copper 8-hydroxyquinolate started to dissolve and transformed to plate crystals. In the second half of the coprecipitation, both crystals, owing to the identical crystal structure, precipitated simultaneously and form a solid solution. When cadmium 8-hydroxyquinolate was precipitated by the PFHS method (precipitation from homogeneous solution) in the presence of the needle crystals of copper 8-hydroxyquinolate, the above mentioned phenomenon was observed. The precipitation of cadmium 8-hydroxyquinolate in the plate form is due to the seeding effect of the plate crystals of copper 8-hydroxyquinolate, which were scantily transformed from the needle crystals. The plate crystals of cadmium compound acts as a seed to transform the needle crystals of copper compound to plate crystals.

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Polyhydric alcohols, acetaldehyde and carbon disulfide were determined by the combination of atomic absorption spectrophotometry (AAS) and the quantitative reaction of those compounds with metal ions. Periodic acid reacts with polyhydric alcohol in sample to yield iodate which precipitate by silver nitrate. After being washed with diluted nitric acid and water to remove excess of silver nitrate, the precipitate is dissolved in ammonia-water for the determination of silver by AAS. Acetaldehyde in sample (ethyl alcohol) reacts with Tolien's reagent to yield silver. The precipitated silver is filtered, washed with water, and then dissolved by addition of conc. nitric acid and water for the determination of silver by AAS. The complex of carbon disulfide with copper ion is formed by shaking the sample solution (carbon tetrachloride or benzene) with copper solution containing diethylamine and ammonia, and extracted into carbon tetrachloride or benzene layer. A portion of carbon tetrachloride layer is taken, and evaporated to dryness. The residue is dissolved by addition of conc. nitric acid and water. A portion of benzene layer is mixed with methyl alcohol. The amount of copper ion in these solution are measured by AAS. The limits of determinations are as follows : glycerin 0.16 mg, lactose 0.82 mg, saccharose 1.93 mg, glucose 0.21 mg, tataric acid 1.22 mg, benzoine 1.07 mg, acetaldehyde 1.90×10^-3 mg, and carbon disulfide 2.52×10^-5 mg. Many samples (ethyl alcohol, carbon tetrachloride, benzene) on the market were examined by those methods.

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The following procedure is recommended to the gas chromatographic determination of low-molecular-weight fatty acids (C₂C₅) vapors which are commonly present as malodorous substances in ambient air. The sampling procedure involved trapping of the vapors with 50 ml of a 1% aqueous solution of sodium hydroxide in two impingers connected in series (flow rate 21/min). Fatty acids were liberated by the addition of 5 ml of 10 N phosphoric acid and extracted with 25 ml of ethyl ether. The extract was concentrated to about 0.5 ml by bubbling with nitrogen gas under cooling with an ice/sodium chloride mixture. m-xylene as an internal standard and ethyl ether were added to the extract to give a final volume of exactly 1 ml. Three μl of this solution was then injected into a gas chromatograph equipped with a flame ionization detector (FID) using an acid washed glass column (2 m×0.3 cm) packed with 7.5% polyoxyethylenesorbitanester and 2.5% polyethyleneglycol 20M coated on Shimalite TPA {(3060) mesh}.
In this method, the extraction efficiencies for several low-molecular-weight fatty acids were 15% for acetic acid, 45% for propionic acid, 80% for butyric acid and 90% for valeric acid. Calibration curves were corrected in accordance with these results. The average recovery based upon the calibration curves was about 95% in the concentration range from 0.14 to 28 ppm. Accuracy based upon coefficient of variation was about 10%. The detection limit of fatty acid vapors in 1 m³ of ambient air was 3 ppb. The malodorous substances in pig feces drying room were analyzed and fatty acids determined were 15 ppb for propionic acid, 2 ppb for iso-butyric acid, 4 ppb for n-butyric acid, 3 ppb for iso-valeric acid and 1 ppb for n-valeric acid.

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The mass spectra of excess-kinetic-energy ions (KE ions) of hexene isomers (13 kinds) have been studied by using a conventional mass spectrometer with a modified ion source. As KE ions are formed mainly from direct cleavage, their mass spectrum (named KE mass spectrum) corresponds well to the structure of a compound. KE ions of hexenes are formed mainly from β-cleavage (fission of a bond β to a double bond) and α_s-cleavage (fission of a bond between one substituent and one sp² carbon to which two substituents are attached). As fragmentation occurs quite regularly, all hexenes have been classified from their KE mass spectra. The spectra obtained by 40 eV and 70 eV electron impact give the information about the structure and stability of the fragment ion and the fragmentation mechanism. These information combined with those from ordinary mass spectrum are quite useful to determine the structure of all hexenes (except distinguishing cis-trans isomers). A linear relationship has been found between the relative abundance of methyl ions (m/e 15) in KE mass spectrum and the sum of chemical shift for methyl carbons in ¹³C-NMR spectrum. It provides the possibility of calculating the KE mass spectrum from the structure of a predicted compound.

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The effect of supporting electrolytes (KI, KSCN, KBr, KCl, NaClO₄, and KNO₃) on the shape of cadmium wave in the water-ethanol mixture of various mixing ratios has been investigated. Yanagimoto polarograph Model PF-501 was used. The operating conditions: m=0.755 mg/s; frequency, 500 kHz; drop time, 3 s. The experimental conditions: temperature, (25±0.1)°C; concentration of supporting electrolyte, 0.5 M; concentration of cadmium ion, 1×10^-4 M. In all supporting electrolytes, the negative rectification effect increases with ethanol content in the solvent. In KCl solution, the decrease of the wave height with the increase of ethanol content can not be explained by the change of viscosity, but is probably due to the solution resistance. The peak potential of the wave caused by the positive rectification effect shifts in the positive direction with ethanol content up to about 30 wt%, and then in the negative direction. The peak potential of the wave caused by the negative rectification effect gradually shifts in the negative direction. With electroactive anion species (I^-, SCN^-, Br^-, and Cl^-), the peak potential of the wave caused by the positive rectification effect once shifts in the Positive direction and then in the negative direction with the increase of 1/ε (ε: dielectric constant of solvent). With NO^-₃ and ClO^-₄ anion species, the peak potential of the wave caused by the negative rectification effect behaves reversely. The shift of the peak potentials is explained in terms of the decrease of dielectric constant and the degree of complexation (or ion-pair formation).

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The oxidation of gallic acid by bromate with trace vanadium as catalyst was followed spectrophotometrically by measurements of absorbance change at 420 nm. The reaction rate was obtained graphically from the absorbance vs. time curve in the range of about 15 to 40 min. reaction time. The reaction rate was proportional to the concentration of vanadium(V) in the range 0120 ng (under the conditions of 5.3×10^-3 M gallic acid, 6.0×10^-3 M potassium bromate, pH 3.8) and 030 ng (1.1×10^-2 M gallic acid, 2.7×10^-2 M potassium bromate, pH 3.8). Using this relationship, the concentration of vanadium as low as 0.1 ng/ml can be determined. The relative standard deviations at 50 ng and 20 ng of vanadium were 3.5% (n=14) and 4.0% (n=10), respectively.
Iron(III) interfered seriously even when present in 20 times the amounts of vanadium. Up to 60 times, W(VI), Mo(VI) and iodide did not interfer. Many of the other ions examined were found to have no effect or slight effect even when present in 1000 times the amounts of vanadium.
Other factors affecting the reaction rate were also studied.

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8-Quinolinolate of aluminum, gallium, and indium in chloroform exhibit strong yellowish green fluorescence with an emission maximum at 510, 526, and 528 nm, respectively. The time resolved fluorescence spectra and the fluorescence lifetime properties of these chelates were measured with a time-resolved spectrofluorometer. The fluorescence intensity of these chelates decays exponentially with time t, and obeys the following equation:
F=F₀e^-t/τ=F₀e^-k_f·t
where F₀ and F are the fluorescence intensity when the exciting light is irradiating and shut off, respectively; τ and k_f being the lifetime and the rate constant for the process of fluorescence emission. The lifetimes of these chelates in chloroform solution at the ordinary temperature were 17.8, 10.1, and 8.4 ns for Al(C₉H₆ON)₃, Ga(C₉H₆ON)₃, and In(C₉H₆ON)₃, respectively. Thus, 8-quinolinolates of group III metals emit the same type radiation with different lifetimes. Between Al-chelate and In-chelate, there were significant difference in the lifetime by 9.4 ns. Then, the logarithmic plot of the composite fluorescence intensity against time is the overlap of some straight lines with different slopes which indicate k_f of various decay processes. The linear portion of the logarithmic plot of the composite fluorescence intensity corresponded to the longer lifetime component (Al-chelate), and by substracting this component from the whole one, the straight line due to the shorter lifetime component (In-chelate) is obtained. Aluminum and indium contents were then determined by comparing the fluorescence intensity of the sample with that of the standard at a definite time (extrapolated to t=0). By using this composite decay curve, the composition of mixtures of n×10^-4 mol/l -Al- and In-chelates in chloroform could be determined.

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Traces of Cr, Mn, Fe, Co, Ni, Cu, Cd and Pb in mammalian lungs were determined by flameless atomic absorption spectrometry. The samples were ashed in a plasma asher and then dissolved in nitric acid. Interferences of ions and other materials in lung tissue were corrected with D₂ lamp. Trace recoveries, obtained by adding standard solutions after drying the samples, were (90102)%, and coefficients of variation were (1.77.7)%.

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In the atomic absorption spectrophotometry of europium in air-acetylene flame, ammonium perchlorate (NH₄ClO₄) increases the absorption of europium.
In the case of 0.5 M NH₄ClO₄, the increase is by about 1.5 times. In this paper, a method for eliminating the interferences of many coexisting compounds using an enhancing effect and a method for determining Eu₂O₃ in La₂O₃ were investigated. The working conditions using Nippon Jarrell-Ash model AA-1 atomic absorption/flame emission spectrophotometer were as follows; wavelength 4594 Å, lamp current 15 mA, burner height 10 mm, air flow-rate 6.5l/min, acetylene flow-rate 1.8 l/min. Though the enhancing or depressing effects of HCl, HNO₃, HBr and HClO₄ in concentrations below 0.1 M were eliminated by 0.5 M NH₄ClO₄, the remarkable depressing effects of H₂SO₄ and H₃PO₄ on europium could not be eliminated.
The interferences of Na⁺, K⁺, Cs⁺ and Al³⁺ in the concentration of 200 ppm were not eliminated, but those of other cations including rare earth elements were completely eliminated. Lanthanum in the range of (200010000) ppm increased the absorption of europium by about 1.4 times. But the effect of lanthanum in the range of (09000) ppm was also eliminated by NH₄ClO₄. The calibration curve for europium in the presence of NH₄ClO₄ was linear in the range of (0400) ppm with a sensitivity larger by about 1.5 times than that for europium alone. The analytical procedure is as follows. A sample is dissolved in HCl and NH₄ClO₄ is added. Europium in the sample solution is determined by atomic absorption method using air-acetylene flame. For practical samples, the values obtained were in fair agreement with those by the flame emission method using a nitrous oxide-acetylene flame.
The coefficients of variation by the present method were (3.72.4)% {Eu₂O₃ content (13)%}.

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In the commercial material of carbazole containing 2, 3-benzocarbazole as impurity, the fluorescence of anthracene could not be directly measured because of the interference of the impurity. Therefore, a chromatographic method of separation was studied for the fluorometry of anthracene in carbazole. Anthracene was separated from carbazole and 2, 3-benzocarbazole on an alumina column (6φ×50 mm) by the elution with monochlorobenzene. Two milliliters of the sample solution dissolved in monochlorobenzene (500μg/ml) was added to the column, and then development was carried on with monochlorobenzene. Anthracene was passed through the column without adsorption and could be quantitatively recovered within 10 ml of the effluent. Anthracene could be determined by measuring the fluorescence intensity at 404 nm with excitation at 379 nm against 0.25 μg/ml anthracene solution as a reference. By this method, anthracene in carbazole could be determined down to 0.005%.

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A limit test method of free ionizable copper contained as an impurity in copper chlorophyll and in sodium copper chlorophyllin by TLC was established. The sample was developed by n-butanol-acetic acid-water mixture (4:1:2 in volume) on a silicagel plate on glass (Merk Co. Art. 5721), and the separated spot of Cu(II) was detected as a gray spot on a pale orange background when the plate was exposed to ammonia gas after spraying rubeanic acid ethanol solution. The minimum detectable limit of Cu(II) was (0.020±0.005) μg, and then good results of the test were obtained as follows: The detection limits of Cu(II) were 0.02% and 0.1% when used 100μg of copper chlorophyll (10 μl of 1 w/v% acetone solution) and 20 μg of sodium copper chlorophyllin (10 μl of 0.2 w/v% aqueous solution), respectively.

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The constituents of several imported clove oils (Eugenia caryophyllata Thumb) were examined to distinguish the difference in infrared absorption band intensity at 1765 cm^-1. Gas chromatography was carried out with a Shimadzu GC5A PF equipped with an FID {5% PEG-20M, 2 m×3 mm i.d., glass column, (80240)°C, 5°C/min}. Mass spectrometric identification of the constituents was investigated with a Hitachi RMU 6E spectrometer coupled with a K-53 gas chromatograph {5% PEG-20M, 2 m×3 mm i.d., (70220)°C, 4°C/min}. The alkali extraction method using 1N sodium hydroxide solution effectively separated eugenol, main constituent of clove oil, from ether solution of the oil. Non phenollic fractions thus obtained were concentrated and used for GC-MS measurement. The identification of oxygenated compounds in the ether fraction revealed that the differences of the absorption band intensity at 1765 cm^-1 were attributed to the quantity of eugenol acetate.

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A lead dioxide tube for oxidation of nitric oxide was prepared by anodic oxidation of a lead electrode of 30 mm i.d. and 300 mm in length. Electrolysis was carried out in 5% sulufuric acid with a platinum wire as a cathod by a current density of 10 mA/cm² for 30 h, and the deposited lead dioxide was washed with water and dried at (70±5)°C for 3 h. The prepared lead dioxide tube completely oxidized 1 ppm nitric oxide in air stream at a relative humidity higher than 30%. The gas flow rate was 300 ml/mn. It could be increased up to 600 ml/mn without change of oxidation efficiency. The oxidizing power was proved to last for a long time by a continuous test of several handred hours.
Influence of relative humidity of the air stream on the oxidizing power was studied. The oxidizing power depends on the amount of adsorbed on the surface of the oxide than on the relative humidity of the gas stream. The oxidizing power remained unchanged at a temperature range of 10 to 40 °C, showing almost 100% oxidation of nitric oxide to nitrogen dioxide.
The lead dioxide tube thus prepared was set in an automatic continuous nitrogen oxide analyzer, instead of the ordinary potassium permanganate-sulfuric acid solution oxidizer. This apparatus worked satisfactorily for one month without any readjustment. This dioxide tube can be recovered without tedious procedure. It may be possible to reproduce the dioxide automatically with a simple equipment attached to the analyzer, which provides a good removal technique of nitrogen oxides.

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The basic data for a quantitative study of the extraction equilibria of the cobalt(II) and zinc(II) chelate of 2-(2-thiazolylazo)-4-methyl phenol (TAC) were obtained spectrophotometrically. The extraction of cobalt(II) or zinc(II) chelate of TAC into benzene was investigated by keeping the ionic strength 0.1 with sodium perchrolate at 30°C. The absorption spectra of cobalt(II) or zinc(II) chelate at various concentrations of hydrogen ion and metal ion in aqueous phases were measured. It was found that only one species of chelate was formed. The analysis of the relationships between the distribution ratio of cobalt(II) or zinc(II) chelate and the hydrogen ion concentration of aqueous phase, or reagent concentration in organic phase has shown that two reagent molecules are involved in chelation and two protons are released. This indicates the formation of a 1 to 2 neutral chelate. Logarithmic extraction constants of cobalt(II) and zinc(II) chelate were determined to be -6.18±0.12 and -8.99±0.11, respectively. The theoritical calculations showed the possibility of separating cobalt(II) or nickel(II) from zinc(II) by using the extraction constants, but the separation of cobalt(II) from zinc(II) required back-washing. The experimental data were in good agreement with theoretical results.

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Manganese thiocyanate-complex is formed when thiocyanate ion is added to a sample solution containing trace amont of manganese.
The complex can be extracted with a solution of trioctylmethylammonium chloride(capriquat) in ethyl acetate.
The resulting organic phase can be used for the atomic absorption analysis.
To a sample solution containing up to 12μg of manganese was added ammonium thiocyanate to make the concentration 0.8M, and then 5 ml of 10% ammonium acetate solution was added to adjust the pH of the solution to 6.0. The total volume was made up to 50 ml with water. The solution was extracted with 10 ml of 5 vol% solution of capriquat in ethyl acetate.
By using the organic phase, the absorbance in the airacetylene flame was measured at 2794.8 Å.
A calibration curve obtained was straight up to 12μg of manganese content. The standard deviation obtained from 5 runs was 1.02% in the determination of 5μg of manganese.
The presence of more than 100 μg of Fe(III) gave a positive error, but other ions do not interfere the determination.
By applying the present method to the determination of manganese in river water, satisfactory results were obtained.
This method can be used for highly sensitive and highly accurate determination of manganese.

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