The study of the solvent shifts for Eosin-Y was made by use of Eq. (1),
ν₁₀=19300-5.91×10^-8((n_D²-1)/(2n_D²+1))·1/I_p^vcm^-1 (1)
where ν₁₀ is the absorption maximum of an Eosin-Y solution, n_D the solvent refractive index and I_p^v the solvent ionization potential respectively. This equation explains well the displacement of absorption maxima of low-lying electronic bands of Eosin-Y in various solutions. The dispersion shift estimated from the equation is -700 - -1000cm^-1 in aprotic solvents. In proton donative solvents that band exhibits anormalous blue shift deu to hydrogen bond. This hydrogen bond shift was determined to be 200 - 400cm^-1. It is strongly suggested that the dispersion interaction plays a great role on the solvent shift for Eosin-Y.

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The adsorption isotherms of SO₂ and H₂O on iron hydroxide oxides (α-, β-, and γ-FeOOH) were determined gravimetrically at 30.0°C and the irreversible adsorption was estimated by evacuating the sample at 10^-5 Torr for 24h at the same temperature, The mole number of chemisorbed SO₂ calculated as that per unit surface area of the oxide was nearly equal to the value of H₂O which is adsorbed irreversibly (Table 1), showing that the number of adsorptive sites for SO₂ is similar to that for H₂O. The amount of irreversible adsorption of SO₂ and H₂O from the mixture of SO₂ and H₂O was close to the sum of amounts of irreversible adsorption from each of the pure gases (Table 2). The SO₂ pre-adsorbed on the FeOOH surfaces did not alter the amount of irreversible adsorption of H₂O, and also the pre-adsorbed H₂O did not influence the irreversible adsorption of SO₂ (Tables 3 and 4). It has been suggested that SO₂ and H₂O are adsorbed at different sites on the surfaces, presumably on the surface ions O^2- and OH^- respectively. Figs. 1, 2, and 3 give the structural models showing the probable surface sites attached with SO₂ and H₂O molecules.

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The Concentration of active sites on a Ni/γ-Al₂O₃ catalyst was determined with methanation reactions of CO and CO₂ and compared with the amount of CO chemisorbed on the catalyst at 25°C. In CO and CO₂ methanation at around 200°C by using a pulse technique, the pronounced tailing of chromatographic peaks of CH₄ produced was observed. As CH₄ giving the tailing part was produced after the passing away of the gaseous reactant with the carrier gas, H₂, over the catalyst, the vacant sites formed after the desorption of CH₄ remained unoccupied by the reactant. This suggested that the concentration of active sites could be evaluated from the amount of CH₄ produced when the amount of the reactant pulsed was large enough to cover the Ni surface. In CO methanation the amount of CH₄ produced reached constant as the amount of CO pulsed was increased. The concentration of active sites on the catalyst determined from this constant value agreed well with the amount of CO chemisorbed at 25°C. On the other hand, in CO₂ methanation because of the weak adsorption of CO₂ on the catalyst the amount of produced CH₄ increased as the amount of CO₂ pulsed was increased. The nature of active sites was discussed with these experimental results and considerations of the effect of thiophene poisoning on the methanation.

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The reaction of sodium nitrate and silica has been investigated by simultaneous measurements of thermogravimetry (TG), differential thermogravimetry (DTG), differential thermal analysis (DTA) and gas chromatography (GC) up to 900°C. In contrast to the thermal decomposition of sodium nitrate, the formation of nitrogen was not observed and the gases formed during the reaction consisted of oxygen and nitrogen monoxide. A small amount of sodium nitrite existed in the system during the reaction. The main reaction product was sodium metasilicate (Na₂SiO₃) irrespective of the silica content. From the results of TG-DTG-DTA-GC between 600 and 800°C the reaction seemed to be apparently zeroth order. However, as the thermal decomposition of the melt and the reaction between silica and the melt took place at the same time it seemed inadequate to describe the reaction at this temperature range in a single rate equation. The reaction in this system was complicated, and either a successive reaction, such as from nitrate to nitrite, peroxide and oxide or a concurrent reaction was supposed to take place.

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The oxidation of manganese (IV) in the form of hydrous manganese (IV) oxide to manganate (VI) by potassium permanganate in alkaline solutions has been investigated over total manganese concentration range from 3.0x10^-2 to 1.5mol per system volume. The rate of oxidation increased with increasing reaction temperature and concentration of potassium hydroxide. Decomposition reaction of permanganate liberating oxygen and yielding manganate (VI) took place simultaneously. In addition to the hydrous manganese (VI) oxide, different forms of anhydrous dioxide were also tested. In this case the rate of decomposition of permanganate increased in every instance, while the oxidation reaction of the oxides to manganate (VI) slowed down. to a significant extent. When the total manganese concentration level was low, the formation of manganate (V) came out in potassium hydroxide solution of high concentrations owing to the decomposition of manganate(VI). However, manganate (VI) was stable at low potassium hydroxide concentration. At the high manganese concetration levels, the oxidation reaction proceeded significantly to such an extent that potassium manganate (VI) crystallized from a suppersaturated solution.

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The thermal decomposition of (NH₄)₂SO₄ and its reaction with Fe₂O₃ were studied by thermal analysis, X-ray diffraction, gas chromatography and chemical analysis. When (NH₄)₂SO₄ was heated at a heating rate of 10°C/min, (NH₄)₃H (SO₄)₂, NH₄HSO₄ and (NH₄)₂S2O₇ were formed as intermediate decompotition products which changed finally to gaseous products. The condition of experiment exerted an influence upon the reaction scheme. An experiment under high pressures restrained the decomposition of (NH₄)₂SO₄, leading to a finding of the melting of (NH₄)₂SO₄ at 368°C, which can not take place under the normal atmosphere.
The thermal reaction of (NH₄)₂SO₄ with Fe₂O₃ under the normal pressure yielded (NH₄)₃Fe(SO₄)₃ over the temperature range 224-310°C, NH₄Fe(SO₄)₂ at 310-370°C, Fe₂(SO₄)₃ at 370-444°C and finally Fe₂O₃ at 564-674°C. Valency of iron remained tervalent throughout the reaction and neither the oxidation of iron nor its reduction did occur.

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Chromium exists in natural water as Cr(III) and Cr(VI), although the stable species of it is considered to be Cr(VI) from thermodynamical viewpoint. As the presece of Cr(III) is likely due to the slow oxidation of Cr(III), the evaluation of the rate is important for the geochemical studies on chromium in natural water. The purpose of this study is to characterize the factors affecting the oxidation of Cr(III) in a solution. The oxidation of Cr(III) to Cr(VI) by oxygen without Mn(II) was too slow to determine its rate by laboratory techniques. In the presence of Mn(II), however, the oxidation by oxygen was markedly accelerated and its rate could precisely be determined. A Na₂CO₃-NaHCO₃ buffer solution was poured into a measuring cylinder and oxygen was bubbled. After reaching a constant temperature, Mn(II) and Cr(III) were added to the above solution. At appropriate time intervals, aliquots of the test solution were withdrawn. The radioisotope ⁵¹Cr was used as a tracer and Cr(VI) formed was separated from the mixture by extracting it with tetrabutylammonium hydroxide-chloroform. Mn(II) would be oxidized by oxygen to a higher oxidation state, which would oxidize Cr(III) to Cr(VI). The oxidezed Mn species would further deposit as stable higher oxides. The rate of oxidation of Cr(III) has dereased with a lapse of reaction time (curve a in Fig. 1). The initial rate (line b in Fig. 1) was detemined by the extrapolation of the curve. The initial rate has been given as a function of concentration of reactants (Figs. 3-7) and the empirical rate equation was derived to be: -d[Cr(III)]/dt =k₀P_O2^0.5[Mn(II)]²[Cr(III)]/[OH^-]^-1.810^7.0[CO₃]. The apparent rate constant k₀ was found to be 1.7x10¹⁴min^-1 at 50°C and the apparent activation energy to be 12kcal. It was suggested that the oxidation of Cr(III) is rapid in ground water containing appreciable amounts of Mn(II).

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Amperometric titrations of CH₂=NOH, HCHO, and their mixture with potassium iodate have been studied. The reduction current of potassium iodate at a rotating platinum electrode (2000rpm) was measured at a potential of +0.8V vs. silver plate electrode. Formaldehyde oxime (CH₂=NOH) can be easily titrated with potassium iodate after adding hydrochloric acid and sodium chloride. Formaldehyde (HCHO) reacts with excess hydroxylamine to produce CH₂=NOH, which can be titrated similarly. Excess hydroxylamine does not disturb the titration. Therefore, two titrations before and after the reaction the amounts of CH₂=NOH, and the sum of CH₂=NOH and HCHO, respectively.
The recommended procedures are as follows.
(1) Determination of CH₂=NOH: Five ml of 4×10^-3 mol/l CH₂=NOH was introduced into the titration cell, and 15ml of 8mol/l hydrochloric acid, 13g of sodium chloride and water were added to make the total volume up to 50ml. The resultant solution was titrated with 10^-2mol/l potassium iodate. solution at a rate of 0.05ml/10sec at room temperature. CH₂=NOH was determined with the relative error and the coefficient of variation less than 0.3% at its concentration from 4×10^-4 mol/l to 4×10^-3 mol/l.
(2) Determination of HCHO: Ten ml of 2×10^-3 mol/l HCHO was introduced into the titration cell, and 0.7ml of 4×10^-2 mol/l hydroxylamine hydrochloride and 0.5ml of 1mol/l potassium hydroxide were added to adjust the pH of the resultant solution higher than 12. The solution was titrated in the same manner as described in (1). HCHO was determined with the relative error and the coefficient of variation about 0.1% at its concentration from 4×10^-4mol/l to 2×10^-3mol/l.
(3) Determination of CH₂=NOH and HCHO in mixtures: A mixture containing 5ml of 4×10^-3mol/l CH₂=NOH and 5ml of 4×10^-3 mol/l HCHO was analysed by using two aliquots. One aliquot was used to titrate CH₂=NOH with 10^-2mol/l potassium iodate solution (0.05ml/5sec) at room temperature after the addition of 25ml of 8mol/l hydrochloric acid, 4ml of 4mol/l potassium bromide, 8g of sodium chloride and water to make the volume up to 50m/l. Another aliquot was used to titrate the sum of CH₂=NOH and HCHO in the same manner as described in (2). The amount of HCHO was estimated from the difference of the two titration. Mixtures containing CH₂=NOH and HCHO, from 1 : 6 to 10 : 1, were determined with the relative error less than 2.3%. The effect of concomitant compounds was examined.

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Dithiothreitol (DTT) gave two anodic waves at d. m. e. in buffer solution of pH 1 to 12. The first wave (E_1/2=-0.434V vs. SCE) at pH4.5 had the nature of adsorption wave and was assigned from DC and AC polarographic studies to a reversible anodic oxidation of DTT to form a monolayer of mercury salt of DTT on d. m. e. surface;
R(SH)₂ + 2Hg ←→ [R(SHg)₂]_ad + 2H⁺ + 2e⁺
The application of Brdicka equation to the saturation current of first wave gave the surface area of 4.9×10³(nm²) per [R(SHg)₂]_ad salt. From the E_d (dissolution potential of the first wave) vs. pH curve, the acid dissociation constants (pK_a) of DTT were determined as pK_a1=9.3 and pK_a2=10.6.
In acetate buffer solution of pH4.5, DTT was subjected to the anodic electrolysis on mercury pool electrode, the potential of which was controlled precisely 2 to 3 mV more positive than E_d. The electrolysis proceeded only very slowly and the product was identified to be cyclic disulfide form of oxidized DTT (OX-DTT) by means of spectrophotometry and polarography. This result can be explained only by assuming a sluggish formation of OX-DTT either from [DTT-Hg₂(I)]_ad through the eq. (1′) or from DTT through the eq. (3) on mercury electrode covered by [DTT-Hg₂(I)]_ad. The 2nd wave (E_1/2=-0.228V vs. SCE) at pH4.5 was assigned to the anodic multi-layer formation of DTT-Hg₂(I). Its limiting current was nearly diffusion-controlled. The electrolysis of the solution of pH4.5 at the potential of limiting current more positive than -0.344V made the solution turbid due to the formation of mercury salt.

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The redox reaction of p-nitrotoluene with sodium polysulfide has been investigated for the industrial preparation of p-aminobenzaldehyde and the reaction conditions were optimized. The best yield (Y=95%) of p-aminobenzaldehyde was obtained when sodium polysulfide freshly prepared from hydrogen sulfide (or sodium polysulfide), sulfur and sodium hydroxide were allowed to react with p-nitrotoluene in the presence of 2wt% N, N-dialkylformamide in ethanol at 80°C for 4h.

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The reaction of phenol with 1-chloro-3-methyl-2-butene (prenyl chloride) in the presence of alkali metal was found to be completed in only 30 minutes at relatively low temperature (30-40°C). Other alkyl halides, such as cinnamyl chloride, benzyl chloride, trans-1-chloro-2-butene and trans-1-chloro-2-hexene, reacted with phenol under the same conditions, and the corresponding o-alkylated phenols were obtained in the yields of 71, 87, 88 and 84%, respectively. In the case of saturated alkyl halides, such as ethyl chloride, butyl chloride, peatyl chloride and isopentyl chloride, however, the corresponding products could not be obtained. The selectivity for o-substituted phenols was found to be governed by solvent, reaction time, reaction temperature and water present in a solvent. On the basis of thege results, the reaction scheme is discussed.

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New syntheses of 1, 5-disubstituted 2-thio-5, 6-dihydrouacils have been investigated from the reactions of acryloyl and methacryloyl isothiocyanates with hydrazides in polar solvents at 60-80°C. 1, 4-Disubstituted 3-thiosemicarbazides were found to be produced as intermediates which could be isolated in reactions at room temperature and then cyclized by heating the reaction mixtures to give 1, 5-disubstituted 2-thio-5, 6-dihydrouracils. The cyclization reaction is considered to take place through the nucleophilic attack of the nitrogen atom on the β-carbon of the acryloyl group of thiosemicarbazides. The 1, 4-disubstituted 3-thiosemicarbazides were treated with a dilute hydrochloric acid to give 1-amino-2-thio-5, 6-dihydrouracil hydrochloride.

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The relationship between the HLB (hydrophile-lipophile balance) value of the scum (surfactant-metal complex) and the efficiency of ion flotation was investigated by using 15 kinds of synthetic complexane-type surfactants (Rc).
The optimum pH region in the Cu(II) flotation shifted to a lower pH range with the increase of chain length of the alkyl group in N-alkyliminodiacetic acid (RidaH₂), whereas, in the case of N-(1-carboxyalkyl)ethylenediaminetriacetic acid (RedtaH₄), it shifted to a higher pH range with the increase of chain length of the alkyl group, and the decrease of numbers of the coordination sites in Rc (Figs. 1-3).
The HLB values of Rc-Cu complexes were calculated according to the Davies or Oda equation on the base of postulated chemical formula. The effective HLB value of Rc-Cu complexes in the Cu(II) flotation ranged from 4 to 14 (Table 4).
Hg(II) was floated selectively from an aqueous solution containing Hg(II), Fe(III), Cu(II), Pb(II), Cd(II), Zn(II) and Ca(II) at pH0.8 by using R₁₀edtaH₄, but, at pH2, the order of selectivities for these metal ions was found to be identical with the order of formation constants of R₁₀edtaH₄-metal complexes (Fe(III) > Hg(II) > Cu(II) > Pb(II) > Cd(II) > Zn(II) > Ca(II)) (Fig. 5). Selectivity in the ion flotation was interpreted from the formation constants and the HLB values of the scum (Rc-metal complexes).
Rc could be easily recovered from the scum by treating with 2N H₂SO₄.

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New polyimides containing the bicyclooctene ring in the chain were synthesized in m-cresol by the condensation reaction of bicyclo[2.2.2]oct-7-ene-2, 3:5, 6-tetracarboxylic dianhydride (BTA) with various diamines. The reactions with aromatic diamines were carried out at 190°C for 17 hr and those with aliphatic diamines at 170°C for 8 hr. The reaction mechanism for the formation of these polymers was investigated by the infrared spectra of the initial reaction products. The reaction appeared to proceed in two steps ; (1) the polyaddition reaction and (2) the imidation of the precursor, similar to the mechanism of polyimide formations.
The imidation took place at 110°C in the case of aliphatic diamines and at 100°C for aromatic diamines. Intrinsic viscosities of the polymers ranged from 0.23 to 1.33. The polyimides showed thermal stability to heating at above 400°C. These polymers except for those from m-phenylenediamine, p-phenylenediamine and 2, 4-toluenediamine were soluble in m-cresol and conc. H₂SO₄.

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To investigate the thermal decomposition mechanism of polystyrene in detail, 2, 4-diphenyl-1-butene was decomposed by using a flow reactor under the following conditions : temperature, 450-525°C ; residence time, 0.1-4.5 sec ; nitrogen to sample ratio by mol, 7.4. The bond dissociation energy of the allylic C-C bond in 2, 4-diphenyl-1-butene calculated from the heat of formation of radicals was lower by about 12 kcal/mol than those in 1-alkenes and the benzylic C-C bond in alkylbenzenes. The rate followed the first-order equation and the rate constant was calculated as k(sec^-1) =3.61×10¹¹exp(-47000/RT). In terms of the above results, 2, 4-diphenyl-1-butene was a thermally labile compound in comparison with 1-alkenes and alkylbenzenes. It was also concluded that cleavages of the allylic C-C bond occurred at the end of the chain, which have been considered as the initiation of the second stage in the thermal decomposition of polystyrene, did not occur.

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Hill's solution describing the kinetics of diffusion-controlled dyeing process is often used to obtain the diffusion coefficient of dye into a fibre from an infinite dyebath. However, it cannot be used conveniently for the numerical calculation of diffusion coefficient from the experimental rate-of-dyeing curve. For that reason, the new expressions describing the diffusion of dye into a fibre from an infinite dyebath were derived by integral and Galerkin's techniques, and the approximate methods that make it possible to calculate the diffusion coefficient were proposed. These simple analytical approximations allow an easy determination of the diffusion coefficient from the dye concentration profile into a fibre and the rate-of-dyeing curve obtained in an infinite dyebath.

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Magnetic susceptibility (0.5 ≤ x ≤ 0.95) and the electrical conductivity (0.78 ≤ x ≤ 0.95) of V_xW_1-xO₂ powder samples were measured at a temperature range from 77 to 300 K. The metal to semiconductor transition was seen at x =0.95 (Fig. 1 and Fig. 2). The transition temperature agreed well with that reported in the literature. Each susceptibility curve at x =0.78, 0.80 and 0.82 (Fig. 1) showed an anomaly. It suggested that this was due to any transition other than the metal to semiconductor transition seen at x =0.95. Its transition temperature decreased with increasing x-value. Conductivity also showed similar anomaly at x =0.78, 0.80 and 0.82 (Fig. 2) suggesting the existence of a certain transition. A sample of x =0.65 showed temperature independent paramagnetism (Fig. 1). Formerly reported antiferromagnetism of the tri-rutile phase at x =0.67 could not be observed at x =0.65.

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Fine particles of alumina were observed to be embedded in a mirrorlike surface of a palladium sheet finished by abrasion with an aqueous suspension of γ-alumina. This surface Beilby layer was broken up in the tribophysical process to give rise to a sludgy emulsion, in which palladium fine particles were uniformly dispersed. The emulsion obtained in this way was found to serve as an active catalyst for oxidizing of benzine vapor. A berthollide compound PdO_1-x was detected in the active catalyst.

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When heated in the presence of manganese(IV) oxide α-phenylsuccinimide gave α-phenylmaleimide as a major product and dl- and meso-2, 3-diphenylbutane-1, 2 : 3, 4-bis (N-methylcarboximide) as oxidative coupling dimers. Several N-substituted β-phenylmaleimides were obtained in 60-73% yields by this procedure. The oxidation of phenylsuccinimido group attached to polymers was attemped.

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Vanadium, molybdenum and other valuable metals have been found to be easily and selectively extracted from and leached solutions of waste-catalysts from a petroleum refining factory and sulfuric acid factory by the reactions with N-alkanoylpolyamines i. e., N-decanoyldiethylenetriamine or N-dodecanoyldiethylenetriamine. Firstly, the N-alkanoylpolyamines are added to the leached solutions in the proper proportion to the amount the valuables. Then, after the pH adjustment of the solutions, either the deposit of the reaction is collected by filtration or the foam treatment is adopted. The methods are applicable to the selective extraction of valuable metals of the leached solution in concentrations of milligrams per liter or grams per liter.

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Treatment of N, N-dialkylneryl- or geranylamine, [1a] or [1b], with boron trifluoride in acetic acid gave N, N-dialkyl-α- and γ-cyclogeranylamine, [2] and [3]. The production ratio of [2] and [3] was dependent on the conditions of the reaction (Table 1 and 2). [2] and [3] were isomerized with aqueous sulfuric acid to yield N, N-dialkyl-β-cyclogeranylamine [4] (Table 3), which was also obtained directly from the reaction of [1] with 40% H₂SO₄.

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Autoxidation of alloocimene [1], myrcene [2], and dihydromyrcene [3] in polar aprotic solvents was carried out. In dimethyl sulfoxide (DMSO) or N, N-dimethylformamide (DMF), the oxidation of [1] gave predominantly 5-isopropyl-2-methyl-2, 4-cyclohexadien-1-ol [10] and 2-isopropyl-5-methyl-2, 4-cyclohexadien-1-ol [13]. In DMSO, the oxidation of [2] gave 2, 6-dimethyl-7-octen-3-one [19]. In DMF, [2] gave linalool [6] whereas [3] gave 6, 7-epoxy-3, 7-dimethyl-1-octene [18] as major products with high conversion ratio and selectivity.

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During the course of pursuing the effect of composition of the mixed ligand comlex of cobalt (II) with cyanide and 2, 2′-bipyridyl(bpy) on the polymerization of methyl methacrylate (MMA), the mono ligand complex of cobalt(II) with bpy, whose ratio of former to latter being 1 : 2-4, was also found to show a polymerization ability in the presence of nonionic surfactant under a nitrogen atmosphere. 2, 2-Diphenyl-1-picrylhydrazyl, nitrobenzene, and oxygen (small amount) interfered with this polymerization. The composition curve of the polymerization of styrene with MMA by this initiator was the same as that of ordinary radical polymerization. It was considered on the basis of the above results that the polymerization of MMA by bis (bipyridyl)cobalt(II) complex proceeded via a radical mechamism.

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