A new type of automatic amperometric titrator was constructed altering the imput circuit of the automatic recording apparatus for potentiometric titration developed by S. Miyake (Hiranuma Type RAT-1).
Its usable conditions and precisions of analytical results were investigated by means of short-circuit amperometric argentometry of halides using a rotating platinum wire electrode (1000 rpm) and an SCE.
The titration curves obtained by the proposed apparatus were well defined, and it was found to be possible to titrate halides more rapidly, precisely and sensitively than potentiometric titration.
Chloride solution could be rapidly titrated using the proposed apparatus at the concentration range of 10^-210^-4N. It was determined by the stepwise addition method of titrant (silver nitrate solution) in 9 minutes at 10^-2N chloride with the relative deviation (dev.) of + 0.10% and the coefficient of variation (c. v.) of 0.11%, in 5 minutes at 10^-3N with +0.13% (dev.) and 0.12% (c. v.), and in 7 minutes at 10^-4N with +0.85% (dev.) and 0.43% (c. v.).
On the other hand, it was determined by the continuous addition method of titrant in 2 minutes at 10^-2N chloride with -0.05% (dev.) and 0.05% (c. v.), in 1 minute at 10^-3N with + 0.06% (dev.) and 0.20% (c. v.), and in 1 minute at 10^-4N with +2.36% (dev.) and 0.45% (c. v.).
Bromide, iodide and thiocyanate solutions were titrated respectively by the proposed stepwise addition method of titrant at the concentration range of 10^-2 10^-5N.
Bromide solution was determined in 6 minutes at 10^-2N bromide with -0.01% (dev.) and 0.05% (c. v.), in 3 minutes at 10^-3N with -0.05% (dev.) and 0.11% (c. v.), in 4 minutes at 10^-4N with +0.27% (dev.) and 0.16% (c. v.), and in 5 minutes at 10^-5N with -2.21% (dev.) and 0.87% (c. v.).
Iodide solution was determined in 9 minutes at 10^-2N iodide with +0.05% (dev.) and 0.15% (c. v.), in 4 minutes at 10^-3N with +0.05% (dev.) and 0.18% (c. v.), in 4 minutes at 10^-4N with +0.18% (dev.) and 0.28% (c. v.), and in 5 minutes at 10^-5N with + 3.40% (dev.) and 0.53% (c. v.).
Thiocyanate solution was determined in 7 minutes at 10^-2N thiocyanate with +0.02% (dev.) and 0.06%(c. v.), in 3 minutes at 10^-3N with +0.10% (dev.) and 0.13% (c. v.), in 4 minutes at 10^-4N with -0.22% (dev.) and 0.21% (c. v.), and in 5 minutes at 10^-5N with -3.13% (dev.) and 1.74% (c. v.).

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In an equilibrium system, there are some chemical species to be separated unsatisfactorily. Accordingly, in order to study the chemical species in such an equilibrium system, it is necessary to determine them without separation.
This paper describes a method whereby the absorption spectra and the concentration of the chemical species in an equilibrium can be evaluated without separation by complementary tristimulus method. (CTSmethod)
For this purpose, Q_r and E which are the important parameter of the CTS-method are obtained by a graphical method and by a calculation, respectively.
In CTS-method, absorption spectra are divided into three portions which are named " range ". A series of absorbance are measured at a regular mμ interval in each of the three ranges, and the sum of the absorbance in each range is represented by U, V or W, respectively, and the total amount of U, V and W is represented by J.
Q_r is the generic name of Q_u, Q_v and Q_w and corresponding to U/J, V/J and W/J, respectively. E equals to J of 1 mol solution. Q_r of a chemical species in an equilibrium, can be obtained from the Q_r plot in which two kinds of Q_r among three are coordinates of a point on the graph, and its value could be determined from the intersection of the two lines which represent two chemical dissociation in succession.
The values obtained by this graphical method agree well with those obtained by a complicated mathematical maticel, method.
To determine the analytical concentration of A and B by CTS-method in a two components equilibrium system in which the component A is satisfactorily, separable but B is not, the values of Q_ra, Q_rb, E_b and E_b must be known either by measurement or calculation.
Here, Q_ra, Q_rb, E_a and E_b represent Q_r and E of A and B, respectively.
The values of Q_ra and E_a can be obtained from the solution of its pure component, and that of Q_rb from the graphical method mentioned above. The value of E_b is calculated from the following equations by substituting the values of Q_ra, Q_rb and Ea into them.
U_m = Q_ua·E_a·C_a+ Q_ub·E_b·C_b
V_m =Q_va· E_a· C_a+Q_vb· E_b·C_b
W_m =Q_wa· E_a·C_a+ Q_wb·E_b·C_b
U_m, V_m and W_m represent the sum of the absorbance of the mixture in the u-range, v-range and w-range, respectively, and Ca and Cb the analytical concentration of A and B component, respectively, and the sum of them are always constant.
Q_ua, Q_va and Q_wa are the values of Q_ra in the u-range, v-range and w-range, and Q_ub, Q_vb and Q_wb are that of Q_rb in the corresponding ranges.
By this method, it is possible to determine a series of dissociation constants of colorants and molar fraction of mixture of two kinds of colorants.

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In order to examine whether the same linear relationship between the retention index of the solute and the composition of mixed stationary phase holds for aromatic oxygen compounds as was found previously for aliphatic oxygen compounds, the retention behaviors of benzaldehyde, acetophenone, benzyl alcohol, phenol, and ethoxybenzene on various mixed packing columns were investigated.
Squalane (SQ), dinonyl phthalate (DNP), tricresyl phosphate (TCP), polyethylene glycol 600 (PEG), polydiethylene glycol succinate (DEGS), or 1, 2, 3tris (2-cyanoethoxy) propane (TCEP) was used as a stationary liquid and Chromosorb W (3060 mesh) as a supporting material. The supporting material was coated with 20 weight % of a liquid, and five series of mixed packing (SQ/DNP, SQ/TCP, SQ/ PEG, SQ/DEGS, and SQ/TCEP) were prepared by mixing the SQ-coated support and the other in the weight proportion 4 : 1, 1 : 1, or 1 : 4 respectively. The retention times of solutes were determined at 100°C.
It became clear from these experimental results that the approximate linearity was held between the retention index of solute and the composition (weight fraction) of mixed phase, particularly, in the region of 0.20.8 weight fraction, although the negative or positive deviation which fairly depended on the nature of solute was observed near zero or 1.00 weight fraction. The interesting fact that the polarity of liquid has scarcely effect upon the retention index of solute on mixed phase or its variation with the composition of mixed phase in the region 0.20.8 weight fraction can be discovered by comparing the retention indices of a certain kind of solute on various mixed phases even though each of the single liquid has a different polarity and gives a different retention index.
The gradients of the straight lines are classified according to the chemical types of solutes in the same way as the aliphatic oxygen compounds, then this knowledge enables us to presume the chemical type of an unknown peak if its gradient is known.
It was found that the difference (ΔI) between the measured retention index and ideal retention index, which can be calculated from the vapour pressures of compounds and therefore can be termed the vapour pressure index, was in proportion to the interaction force between solute and solvent.
As a result of the estimation of relative polarity of single liquid phase and mixed phase by the use of ΔI, it was recognized that, as the relative polarity of the liquid used as a high polar liquid in the mixed packing becomes higher, the relative polarity of mixed packing becomes lower than expected value. It is possible to consider from this result that the addition of small amount of SQ-coated support to a high polar liquid-coated support has the remarkable effect on the suppression of the apparent interaction between solute and solvent.

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The author had previously found that there was an obvious linear relationship between the retention index of the solute and the composition (weight fraction) of the mixed stationary phase in some combinations of liquid. It was the purpose of this paper to discover the conditions which allow to establish these linear relations or the general rule in regard to this relation, and then to observe the retention be havior of various compounds of different types on the mixed packed chromatographic column.
Six kinds of liquid of moderately different polarity, viz. squalane (SQ), dinonyl phthalate (DNP), tricresyl phosphate (TCP), polyethylene glycol 600 (PEG), polydiethylene glycol succinate (DEGS), and 1, 2, 3-tris (2-cyanoethoxy) propane (TCEP) were used as the stationary liquids. Chromosorb W (3060 mesh) which was used as the supporting material was coated with 20 weight. % of any one of these stationary liquids, and fifteen series of mixed packing were prepared by mixing a low polar liquid-coated support and a high polar liquid-coated support in the weight proportion 4 : 1, 1 : 1, or 1 : 4, respectively. The specific retention volume and the retention index of various compounds was calculated from the retention time measured at 100°C.
The relative polarity of single liquid, calculated from the retention index of benzaldehyde in the similar manner as Rohrschneider's method, was as follows : SQ 0, DNP 21, TCP 41, PEG 69, DEGS 82, TCEP 100. It was found that an excellent linear relationship was held between the retention indices of the solutes and the composition of the mixed phase if the relative difference of the polarities (ΔP) of the two liquids building up the mixed stationary phase was less than about 30. In the case ΔP>30, a tendency was found that these relations are not held over the full range of the composition. On the contrary, the retention indices of the large majority of compounds deviate abruptly toward the positive direction from the straight line near 1.00 weight fraction. The deviation of benzyl alcohol, phenol, or aniline which is a typical hydrogen bonding aromatic compound appears differently from the others; a deviation also appears at around zero weight fraction. It was recognized from these experimental facts that an addition of small amount of the high polar liquid-coated support to the low polar liquid-coated support or vice versa increases the retention indices variation remarkably with increasing ΔP. Since these tendencies agree with the miscibilities of combined liquids incidentally, it may be estimated from the observation of the miscibility of stationary. liquid whether the linearity holds or not. By combining some pairs of liquids being ΔP>30, a mixed stationary phase of a wide range of relative polarity which holds the linear relationship excellently can be obtained.

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Some basic parameters functioning in oxidation rate of organic substances using low-temperature plasma asher with maximum high-frequency power of 30 W have been investigated. Approximately 50% of the high-frequency energy was admitted into the oxygen stream and a supposed electron temperature of around 15 eV in the plasma gas was calculated from the given physical dimensions of the apparatus. Linear relationship was found between the oxidation rate and (H. F. power)/(pressure) under certain limited range using sucrose as a test substance, while the latter was proportional to the electron temperature of the plasma. The oxidation rate was accelerated with increased flow rate until the latter reached to 20ml/min, and the oxidation rate was equilibrated by surface reaction rate at higher flow rate.
The plasma concentration in the oxygen stream was monitored by a thermistor probe consisting of a glass-covered thermistor element and a glass handle, a stainless steel net having been mounted on the thermistor probe for catalytic recombination of the dissociated species of the oxygen plasma. The stainless steel net provided a higher efficiency of the recombination than platinum net.
A distribution pattern of the oxidation rate along the plasma tube exhibited nearly a symmetric curve from the central position of the high-frequency coil, so that the quenching speed of the dissociated species produced in the discharge region was supposed to be considerably fast. Oxygen was then replaced with other gases and the same experiment was carried out. Air plasma oxidized sucrose having its distribution pattern of the oxidation rate which was not understood from the oxygen content in air. Complicated reactions between the nitrogen and the oxygen plasmas were therefore supposed. Carbon dioxide which dissociates into CO and O resulted a moderate oxidation with somewhat lower oxidation rate than air, probably because molecular oxygen which partly incorporated with plasma oxidation when oxygen or air was used was absolutely excluded from the carbon dioxide plasma. When pure argon was used as the plasma gas, a fragmentation of the organic substance caused by the electron impact was observed.
A comparison was finally made between the chemical structure and the oxidation rate by using various organic compounds the most of which were aliphatic and aromatic carboxylic acids. Acid anhydrides of low molecular weight exhibited extremely high rate of weight losses because of their volatilities stimulated by the surface oxidation of the materials. No significant difference of the oxidation rate due to the numbers of carboxylic groups and the lengths of alkyl chains was observed, while higher oxidation rate of unsaturated compounds than that of saturated ones was found in general. Low melting point samples gave some increase of weight due to diffusion of organic oxides produced at the surface into the samples.
A mass spectrometric study of the reactant gases found no fraction greater than m/e = 50, that meant practically complete combustion was taken place in the plasma apparatus.

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In the heteropoly acid method that is often used for the spectrophotometric determination of titanium (IV) and vanadium (V), there is such a deffect that the two metals have to be separated beforehand, because the presence of one ion interferes the determination of another ion. In the present work, a new spectrophotometric method for the simultaneous determination of titanium and vanadium in mixture has been studied based on the difference of decomposition rates of molybdotitanophosphate (faster) and molybdovanadophosphate (slower) in 1N hydrochloric acid solution.
Titanium (IV) and vanadium (V) react with phosphomolybdic acid to form molybdotitanophosphate and molybdovanadophosphate respectively, which can be decomposed in 1N hydrochloric acid solution. When the decomposition of two heteropoly acids is stopped by the addition of stannous chloride solution, the corresponding reduced molybdenum blue is formed. The absorbance (A) which corresponds to the total amounts of titanium and vanadium is obtained when the reaction of decomposition is stopped after 1 min. Determination of vanadium in the presence of titanium is performed by measuring the absorbance (B) after 20 min decomposition of the solution, the amount of molybdotitanophosphate becoming negligible in this time. The absorbance (C) of vanadium contribution to the absorbance (A) can be then estimated, and the absorbance (A -C) corresponds to the amount of titanium in the mixture.
The experimental procedure is as follows : The sample solution of titanium and vanadium containing below 100 μg of each metal is taken into a 50 ml beaker, and 5 ml of phosphomolybdate solution is added to it. The pH of the solution is adjusted to 1.8 with 1N hydrochloric acid and total volume to 40 ml with distilled water. The solution is allowed to stand for 2 hours at 25°C, and transferred to a 50 ml volumetric flask. To the solution, 4.5 ml of 10N hydrochloric acid is added, and just 1 min (reaction time) after this moment, 5 ml of stannous chloride solution is added. The molybdenum blue solution obtained is diluted immediately to 50 ml with distilled water. Just 5 min after the reduction, the absorbance (A) is measured at 700 mμ against a blank solution. The same sample solution is taken into another 50 ml beaker, and then the absorbance (B) is measured following the same procedure as above except for reaction time of 20 min.
This method was applied to the synthetic sample solutions containing 20100 μg of titanium and vanadium in 50 ml solution within 3% of relative error. Iron (III), aluminum and lead (II) interfered rather seriously.
Spectrophotometric determinations of titanium (IV) alone and vanadium (V) alone by the molybdenum blue method have been also studied, and it was found that Beer's law holds for the concentration region 0100 μg/50 ml in both cases. The apparent molar absorptivities of titanium and vanadium are 9.48 ×10³ and 1.30×10⁴, respectively.

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Interference suppression to coexisting elements by sodium sulfate for the determination of molybdenum in steel by atomic absorption spectrometry in an airacetylene flame has been examined. An addition of 1% sodium sulfate was effective to prevent the interference of a very large amount of coexisting elements in Mo 20μg/ml for example, Fe 10 mg/ml, Al, Mn, W 0.5 mg/ml, Cr 0.3 mg/ml.
The working conditions were the wavelength 3133Å, the current of hollow cathode lamp for Mo 10 mA, the slit width 0.18 mm, the air flow 13.0 l/min (1.8 kg/ cm²), the acetylene flow 4.5 l/ min (0.5 kg/cm²). The instrument used was Hitachi 207 atomic absorption spectrophotometer.
The steel samples analysed were C steel (Mo 0.014%, Cr 0.05%), Ni-Cr steel (Mo 0.015%, Cr 0.7%), Cr-Mo steel (Mo 0.19%, Cr 1.1%), stainless steel (Mo 0.073%, Cr 18.6%) and high speed steel (Mo 0.51%, Cr 3.9%) of " Japanese standard of iron and steel ".
A 1 gram portion of steel was dissolved in a mixture of 10 ml of concentrated hydrochloric acid and 5 ml of concentrated nitric acid, and warmed gently to commence reaction. When the reaction ceased, the solution was boiled to drive off nitrogen dioxide for 2 to 3 minutes. The solution was diluted with cold water and filtered, and made up the sample solution containing 1 gram sodium sulfate to give a final volume of 100 ml, In the case of high speed steel, it was dissolved in a mixture of 10 ml of concentrated hydrochloric acid, 5 ml of concentrated nitric acid and 10 ml of concentrated phosphoric acid.
The results obtained in this experimence were satisfactory in order to determine molybdenum in steel. In the case of stainless steel, it was however unsatisfactory. This implies that sodium sulfate does not completely eliminate the interference for the high concentration of chromium in stainless steel. The sensibility was 0.6 ppm Mo/1% absorption.

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The authors presented the tables for chemical shifts of alkane, alkene and alkyne carbons.
C-13 NMR chemical shifts were greatly influenced by neighbouring functions, and it was found convenient to arrange the tables so as to collect chemical shifts of carbons which accompanied the same sorts of neighbouring groups, i. e. chemical shifts of C-13 in X-¹³C-Y chemical structure were arraied in conjunction with X and Y functions. This method of classification was advantageous in that the difference of chemical shift of a certain type of carbon such as sp³, sp² or sp which followed only different function might be estimated.
The references cited for the tabulation of C-13 NMR chemical shifts were the same as in the previous papers.
The numbers of chemical shifts collected here were: alkane; ca. 800, alkene; ca. 200 and alkyne; ca. 30.
Fig. 1 in the paper showed the chemical shift ranges of methyls. They distributed from 130 to 200 ppm from CS₂. Metal methylate, silicate, nitrile and alkyne adjacent carbons resonated at the highest field. The terminal methyl of hydrocarbons had such a tendency as the nucleus which followed methylene was at the highest field and the carbons followed by methine and quaternary carbons lowly shifted nearly at intervals of 10 ppm respectively. Methyls which leaded sp² carbons resonated in the range of 160 to 180 ppm regardless of olefinic or aromatic carbons. Ether and alcohol methyls were at the lowest field ranging from 130 to 145 ppm.
Fig. 2 was for methylene carbons. Generally speaking, the chemical shifts dropped about 10 ppm in comparison with methyls when the neighbouring functions were the same, and this relation was also observed between methylene carbons and that of methine and quaternary.
Fig. 4 was for olefinic carbons. They appeared in the range of 40 to 90 ppm except allene carbons. The terminal and centered carbons of allene resonated at higher than 100 and lower than -6 ppm respectively. There occured a case that the chemical shift ranged rather widely as shown in the line of unsaturated acids, it must be caused by steric effects of substituents.
Fig. 5 was for alkynes.
An application of the figures for the analysis of a C-13 NMR spectrum was presented.

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Precise measurements of small mass less than 100 mg are usually achieved by means of weights of small mass calibrated against standard weights and a balance of high precision. It is however rather difficult to maintain the weights for long periods securing their accuracy better than 1 μg. For such fine measurements of mass it is desirable to produce a mass standard as a measure of certain physical property of material which relate to the mass with good stability.
A quartz torsion balance of Rodder Model E (Microtech Services Co., California, U. S. A.) which has very high sensitivity and is successfully used in micro- and ultramicro-chemical analyses has been taken up for the foregoing purpose. A satisfactory reproducibility of readout less than 0.1 μg together with a long term stability of the sensitivity supposedly within a range of 0.15%/10 years was ascertained as a result of statistical study of the dynamic properties of the torsion balance. Effects of ambient temperature and loading mass against the sensitivity of the torsion balance were also investigated.
An empirical equation for the sensitivity S, defined. as the ratio of the readout vs. the mass to be measured, of the torsion balance used was obtained as a function of the temperature t and the loading mass M, as follows,
S =2.32504{ 1-α(t-20)} (1-βM) in div. μg^-1
where α and β were the temperature and the loading mass coefficient of the sensitivity whose values were empirically evaluated as 1.31 × 10^-4 deg^-1 and 5.45 × 10^-6 mg^-1, respectively. A slight decrease in the sensitivity was found either with a rise of the temperature and an increase of the loading mass.
The accuracy of absolute determination of the mass was within 0.01% of the given mass under the torsion range of 1 to 7 mg, while the detectable limit for the mass was 0.1 μg throughout the loading mass of 0 to 100 mg.
By a help of the sensitivity as a stable parameter for the mass measurement, there was found a possibility of using the quartz torsion balance as a working standard within the torsion range of 7 mg.
The precision of the balance was also ascertained as 0.1 μg or less by Borda's tests comparing three homonominal weights up to 100 mg.

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The previous methods for the determination of urushiol are the volumetric and gravimetric methods, which require a great skill.
The stable color of urushiol with triethanolamine (TEA) and iron (III) in a TEA buffer in ethylalcohol has been studied spectrophotometrically as a new method for its determination. Absorption spectra of the chelate of urushiol with TEA and iron (III), and the complex of iron (III) with TEA are shown in Fig. 1. The absorbance of the chelate is maximum at 625 nm, and that of the complex ranges in the region less than 600 nm. The wavelength used is 625 nm. The effect of amount of TEA in the chelate of urushiol is shown in Fig. 2. TEA used for both a reagent and buffer is 29 times of iron in molar ratio. Effect of amount of iron (III) in the chelate of urushiol is shown in Fig. 3. Iron (III) used is twice of urushiol. Thus 4 ml of a reagent-buffer solution (apparent pH 6.78) containing 0.025% ferric chloride and 0.4% TEA is used for the determination.
The proposed procedure is as follows; To 5 ml of ethylalcohol containing urushiol (less than 1.00 mg) is added 4 ml of the reagent-buffer. It is diluted to 10 ml with ethylalcohol. The absorbance is measured with 10 mm cell at 625 nm against ethylalcohol at 20°C.
Beer's law was obeyed up to 1.00 mg of urushiol. The absorbance did not change at least for 12 hours, and the apparent molar extinction coefficient was 1750. Effect of diverse compounds is shown in Table I. Water, acetic acid, d-mannite, d-glucose, oleic acid, rosin and Linseed oil of diverse compounds in lacquer are regarded as having no influence on the determination of urushiol.
The continuous variation curves for urushiol and iron (III) is shown in Fig. 4. It might be suggested that the molar ratio is 1 : 1. But, TEA in the chelate was unknown.
The procedure on raw lacquer is as follows; 0.400 g of raw lacquer is weighed into a 100 ml volumetric flask, the solution is diluted to 100 ml with ethylalcohol and is filtered through a filter paper No. 5c. 5 ml of the filtrate is pipetted into a 100 ml flask, the solution is diluted to 100 ml with ethylalcohol, and 5 ml of the solution is used for the measurement.
The results for the determination of urushiol in raw lacquer is shown in Table II. The reproducibility was 0.4% as a coefficient of variation. The new method is rapid, simple and accurate.

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N-(2-Pyridyl)-N', C-diphenylformazane (PPF), N-(2-benzothiazolyl)-N', C-diphenylformazane (BTPF) and N- (5-nitro-2-pyridyl)-N', C-diphenylformazane (NPPF) were proposed as possible reagents for the determination of small amounts of copper and nickel.
The reagents were acid-base indicators which were present in the three forms in the solutions. The dissociation constants in dioxane solutions at various concentrations were determined spectrophotometrically. It was found that the acid dissociation constants vs. mole fraction of dioxane plots were linear and the values at zero dioxane mole fraction were calculated by an extrapolation.
The reagents formed blue chelates with copper and nickel ions in aqueous dioxane in the metal to reagent ratio 1 to 1 in the presence of an excess metals. The compositions of copper chelates were determined by the continuous variations method and their equilibrium constants were determined spectrophotometrically at 30°C at various concentrations of dioxane. The constants were found to be proportional to the mole fraction of dioxane and the experimental equation were calculated.
The extraction of copper as a NPPF or BTPF chelate into carbon tetrachloride was also investigated by keeping the ionic strength constant by sodium perchlorate at 30°C. The compositions of the copper chelates extracted into carbon tetrachloride were determined by the continuous variations method and was found to be in the 1 to 2 copper to reagent ratio. The extraction of the copper chelates followed a normal procedure; two reagent molecules added and two proton released on chelation which indicates the formation of a 1 to 2 neutral chelate. PPF decomposed slightly in the course of extraction in the presence of copper, but NPPF and BTPF were more stable than PPF in this respect.
New measurements were reported for the values of the correction term log U_H, μ=0.1 and 30°C which must be added to pH meter readings in solution of aqueous dioxane at mole fraction n₂ 00.3863 in order to give the true concentration of hydrogen ion.

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Though the Methylene Blue colorimetric method has been widely used for the determination of the concentration of alkylbenzenesulfonate (ABS) in the polluted waters, this method does not always give a corret result because there exist in the waters some materials, other than ABS, which react with Methylene Blue and affect the analytical value of ABS. The result of the analysis, therefore, is often represented as the concentration of Methylene Blue active substances (MBAS).
On the other hand, the infrared spectral method is considered to give a more precise value for the analysis of ABS. However, infrared spectral method. of methylhepthylamine complex of ABS is too complicated and needs too much time to be a practical use.
The authors attempted to determine the concentration of ABS in the polluted waters more readily combining the Methylene Blue colorimetric method with infrared spectrometry as follows:
(1) The complex of Methylene Blue active substances and Methylene Blue (MBAS-MB) was extracted from the water with an organic solvent (1, 2dichloroethane) in a similar way as conventional methods. From the measurement of the absorbance at the wavelength 655 mμ of the solution the concentration of MBAS in the water was determined.
(2) After the solvent of the solution of MBAS-MB complex was evaporated up, the residue was prepared for the infrared spectrometry.
The absorbance peaks of the infrared spectrum of the MBAS-MB complex at the wavenumber 890 cua^-1 and at 1010 cm^-1 were characteristic for Methylene Blue and ABS respectively. It was found that the ratio of the peak height at the wavenumber 1010 cm^-1 Y, to the peak height at 890 cm^-1, X, of the spectrum was proportional to the ratio of ABS to MBAS in the complex. A calibration curve was constructed for the relation between Y/X and ABS/MBAS by standard solutions. Thus using this calibration curve, the ratio ABS/MBAS in the water was estimated by an infrared spectrum of MBAS-MB complex. Multiplying MBAS concentration given in the procedure (1) by ABS/MBAS, we could estimate the net content of ABS in the water.
The reproducibility and recovery test of this method showed fairly good results. As more than about 0.5 mg of MBAS-MB complex is necessary for the infrared spectrometry, this method is not applicable for the analysis of the water with very low concentration of MBAS. It is, however, considered to be very useful for the analysis of highly contaminated waters or bottom sediments which contain a lot of Methylene Blue active substances other than ABS.

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Fundamental studies were taken for β-ferric oxyhydroxide (β-FeOOH) in rust formed on steel in sea water by an infrared spectrometric method. The results obtained are as follows;
(1) The β-FeOOH synthesized is a spindle shaped crystal with 300 mμ long and 60 mμ width, but no difference are in particle size and crystallization by ageing of its crystal. These are the characteristic properties for β-FeOOH, which differ from the ones of α- and γ-FeOOH.
(2) β-FeOOH has fairly broad absorption bands at 835 cm^-1 and 690 cm^-1 in its infrared absorption spectrum. The 835 cm^-1 band is effective one as socalled key band and the absorbance is worked out with a base line method. If only β-FeOOH is present, a linear calibration curve is obtained between its weight and absorbance.
(3) When β-FeOOH coexists with α-FeOOH, a calibration curve can be drawn up from the ratio of the absorbance at 835cm^-1 band for β-FeOOH with the average absorbance between at 890 cm^-1 and 797 cm^-1 bands for α-FeOOH. In the presence of γ-FeOOH, the calibration curve for β-FeOOH is obtained directly from the absorbance at 835cm^-1, or from the ratio of the average absorbance between 1026 cm^-1 and 735 cm^-1 bands for γ-FeOOH with the absorbance at 835 cm^-1 band for β-FeOOH.
(4) In the practical samples of rust from steel in sea water, the reproducibility with the average absorbance method is superior to the one by only the absorbance.
(5) The identification limit of β-FeOOH coexisting with α- and γ-FeOOH in the infrared spectrum is about 65% and 25%, respectively. Even a amount of β-FeOOH, however, can be identified by, comparing the ratio of these absorbances with that obtained only β-FeOOH's present.

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The impurities in high purity yttrium oxide, such as sodium, magnesium, calcium, copper, iron, lead and zinc, are detected by emission spectrography among which sodium, magnesium and calcium are determined by flame emission and atomic absorption spectrometry using air-hydrogen flame. The influences of several inorganic acids to be used, some metals and high concentration of yttrium on the determination of sodium, magnesium and calcium are investigated.
On the effects of inorganic acids, the emission and absorption of sodium are almost unaffected except that they are gradually decreased with increasing concentration of phosphoric acid. The absorption of magnesium is almost unaffected by less than 0.1M of hydrochloric acid and nitric acid, but considerably decreased by their 1M. It is considerably decreased by sulfuric acid and phosphoric acid. Inversely, it is increased about 50% by perchloric acid. The emission and absorption of calcium are similar to those of magnesium, but they are more decreased by nitric acid, sulfuric acid and phosphoric acid.
On the effects of metal ions, the emission and absorption of sodium are almost unaffected by yttrium, magnesium and calcium. The absorption of magnesium is almost unaffected by sodium, but increased about 50% by yttrium and calcium. The emission and absorption of calcium are not particularly affected by sodium and less than 100 ppm of magnesium, but they are appreciably decreased at the concentration of 500 ppm of magnesium. The emission is increased in the range of 1 to 1000 ppm of yttrium, and rapidly decreased at the concentration of 5000 ppm of yttrium. The absorption is increased at the concentration of 1 ppm of yttrium, and rapidly decreased with increasing concentration of yttrium.
From the above investigation, it is found that hydrochloric acid or perchloric acid is suitable for dissolving the yttrium oxide sample, and sodium, magnesium and calcium are directly determined in the large amount of yttrium by a standard addition method. A sample of 99.9% yttrium oxide is dissolved in hydrochloric acid and determined by flame emission and atomic absorption methods. 40 to 850 ppm of sodium are determined with coefficients of variation of ±0.8 to ±6.8% by flame emission method and ±0.7 to ±2.9% by atomic absorption method, 1.5 to 4.5 ppm of magnesium with c. v. of ±1.1 to ± 5.0% by atomic absorption method, and 42 to 4200 ppm of calcium with c. v. of ±2.4 to ±6.9% by flame emission method and ±0 to ± 10.7% by atomic absorption method.

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It has been found that gasoline vapor contained alkyl lead can be absorbed on active carbon and amount of lead content quantitatively analysed by X-ray fluorescent method.
For briqueting carbon powder, stealic acid was suitable binder, and the employed mixing ratio of carbon and binder was 3:2.
The results were quite consistent with calibration curve which was obtained by impregnation method of lead standard solution over the range from 0.1 mg to 0.5 mg Pb/3 g carbon.

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