The effect of added urea on the crystal structure and pore structure of hydrous titanium(W)oxide (HTiO) was investigated by X-ray diffractometry, electronmicroscopic observation, and N 2 adsorption desorption at -196°C. HTiO was prepared by the thermal hydrolysis from titanium( IV) chloride solution with or without urea. The rate of the precipitation of HTiO was not affected by the addition of urea. The precipitation rate was extremely high compared with the decomposition rate of urea. In the absence of urea, the precipitates obtained after an hour heating at 80°C was a mixture of rutile and anatase type, and had mesopores around 4 nm radius. The anatase type HTiO was gradually converted into rutile and the mesopores disappeared by the subsequent heating at 80°C. In the presence of urea, anatase type HTiO with mesopores around 4 nm radius was obtained by an hour heating at 80°C. Both the crystal structure and pore volume scarcely changed by the subsequent heating for 6 hours at 80°C. When titanium(IV) chloride was hydrolyzed at high temperatures, HTiO with large crystallite size and pore volume was obtained. The influence of the hydrolysis temperature on the crystal structure and po re structure was not so remarkable in the presence of urea as in the absence of urea.

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The catalytic activity of oxidative dehydrogenation of 1-butene (320°C) over two phase-mixed perovskite oxides of La_1-xSr_xFeO₃ (0≤X≤1.0) and SrFeO_3-y, was investigated in connection with the variation of SrFeO3-y crystal structure. The catalytic activity increased with Sr²⁺ substitution. A solid-solution was formed up to x =O.136 but SrFeO_3-y, was present above as a second phase. La_1-xSrxFeOO_3-y phase was active for oxidative dehydrogenation and isomerization of 1-butene. SrFeO_3-y, present as the second phase is readily reduced by 1-butene and undergoes an incomplete structural change to the more oxygen deficient perovskite oxide (SrFe_0.25) by generating CO₂ gas. This change in the structure of SrFeO_3-y, enhanced both the isomerization to 2-butenes and its complete oxidation by O₂ from gas phase.

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A photoactivation type physical developer is proposed which can stand storing for long period. Some basic characteristics; the stability of developer, the deposition efficiency of image silver and the effects of anion species and nucleus metal on the developing rate, were studied. The developer consisted of a meatanol-water solution of silver salt (0.5 mol/l) and p-benzo quinone (0.47 mol/l). The photographic image were formed on photosensitive films of 2- isopropoxy-1, 4-naphthoquinone dissolved in cellulose acetate. The image forming steps wer (1) the imagewise exposure (365 nm, 7.5x1015 photons/cm2. s, 10 s), (2) the first development o nucleus formation (immersion of the exposed film into Ag+ or Pd2+ methanol-water solution 10 s) and (3) the second development or image silver deposition under UV irradiation of th developer. The developing time could be made much shorter when palladium nuclei rather than silve nuclei were used. The overall photographic speed was 4 times faster with palladium nuclei The anion of the silver salt affected the silver depesition rate on the silver nuclei. The deve lopment with AgBF4 was found not to exhibit any significant induction period while th, development with AgNO3 showed an induction period of several minutes. The developer after storage for two days did not show any deterioration in the developing power. From the, practical point of view the photoactivation type physical developer proposed could be store almost for a week. The ratio of the amount of silver utilized for image formation to the whole silver consumption was 1-3%. The resolution power of image varied over 80-241 line pairs/mm, depending on the anion species in the developer and also on the nucleus metal. Photo-activation Type Physical Developer. II.

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The purpose of this study is to produce battery-grade active manganese(IV) oxide by thermal decomposition of manganese(II) sulfate. Anhydrous manganese(II) sulfate was first decomposed at 1000°C in air to form trimanganese tetraoxide and then heated again at 700-800°C in air to obtain manganese(III) oxide. The interfacial reaction was concluded to be the rate-determining step of the overall oxidation process. The remnant after extraction of the manganesea sulfate from the manganese=oxide with hot sulfuric acid was γ-type manganese(II) oxide. This oxide showed a high discharge activity equal to or superior to that for the electrolytic manganese(IV) oxide. The apparent specific volume was large than that for the electrolytic manganese(IV) oxide and was almost equal to that for the activated manganese(IV) oxide ore.

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Magnetite was synthesized from the mixed solution of urea and iron(II) and iron(III) chlorides at about 100°C for 5h, and the intermediate precipitates were examined by X-ray diffraction and EM observation. Brownish-yellow β-FeOOH suspension was initially formed by the hydrolysis of iron(III) ion with a consequent decrease in pH to about 1.1. The hydrolysis of urea due to heating resulted in the pH increase and hence the formation of Fe₃O₄ at about pH 5.0. In the hydrolysis process of iron(II) and iron(III) ions, α-FeOOH was seemed to be formed temporalily as well as α-FeOOH, but they changed to Fe₃O₄ by the reaction with iron(II) ion. Similarly, heating of α- or α-FeOOH suspension containing urea and iron(II) ion resulted in the formation of Fe₃O₄.

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The sinterability of ultrafine 8-SiC powders with the average particle size of 0.01-0.05, μm obtained by three kinds of vapor phase reactions, (CH₃)₄Si-H₂ system at 1200-1300°C, SiH₄, CH₄, -H₂, system at 1400°C and CH₃SiCl₃-H₂ system using plasma jet method, was compared in the presence of boron and/or carbon as sintering aids at 1400-2050°C. The effects of the sintering aids on the grain growth of SiC were also investigated to elucidate the function of the aids in densification of SiC. The following results were obtained.
(1) The sinterability of SiC powders hardly varied with their synthesis methods, except SiC powder consisting of hollow particles produced by the SiH₄ system the sintered bodies with the relative density of above 90% were obtained by the pressureless-sintering in the presence of boron and/or carbon at 2050°C. The crystallinity of SiC powders did not affect the sinterability to observable extent.
(2) The addition of boron or carbon suppressed the grain growth of SiC. This effect was remarkably enhanced by simultaneous addition of boron and carbon. The coexistence of them, which was essential for the densification of SiC, was characterized by the suppression of grain growth in the course of heating up to sintering temperatures.

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The color-developing and discoloring effect of acid, such as HCl, CF₃COOH and CH₃CO. OH, or water on Crystal Violet lactone (CVL), which is used widely as a coloring material for pressure-sensitive copying system, has been investigated by means of UV and visible spectrometry, ¹H-NMR and ¹³C-NMR in the solution of ethanol, benzene, DMSO or water. The behavior of Crystal Violet (CV), Malachite Green (MG) and Malachite Green lactone (MGL), which have similar structures to CVL, were also investigated for comparison. It is recognized that the color-developing of CVL is based on the opening of the lactone ring, and an equilibrium which depends on acid concentration (or acid strength) exists between carboxyl form. It is indicated that the ratio of the carboxyl-form to the lactone-form reaches its maximum at an appropriate acid strength, where the intensity of the developed color is the highest. The increase of the acid concentration reduces the intensity of the developed color still retaining the carboxyl-form. It seems that the phenomenon is caused by the protonation to dimethylamino groups of CVL. The fading or discoloring of CVL (carboxyl-form) with water is caused by the formation of lactone ring.

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In the present experiments qualitative and quantitative analyses of the amino acids formed when methane-ammonia-water system including additional materials such as carbon monoxide, carbon dioxide, various metallic carbonates or formates was submitted to an electric discharge between an electrode and water surface (a wet discharge) were investigated.. The effect of additional materials on the formation of amino acids was also investigated. In addition, methane-ammonia-water-formic acid, methylamine-water-formic acid, amino acids-water-formic acid, and methylamine-water-carbnates or formates system were studied. Upon addition of carbon dioxide system, the total of amino acids increased with an increase of the initial concentration of carbon dioxide and became maximum when the initial concentration of carbon dioxide was half of that of methane. When the initial concentration of carbon dioxide was greater than that of methane, the formation of neutral amino acids was inhibited but acidic amino acids, aspartic acid and glutamic acid were effectively formed. Results obtained from alanin-water-formic acid system revealed that carboxyl radical was important for the formation of acidic amino acids in the methane-ammonia-water-carbon dioxide system. Upon addition of carbon monoxide, the yield of aldehydes and ketones, precusors of amino acids, were higher than that in the carbon dioxide system. It was found that the effect of carbon monoxide was different from that of carbon dioxide. The yield of both acidic and neutral amino acids increased in the carbon monoxide system. And it was found that the addition of cabonates or formates had an effect on the formation of amino acids obtained.

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Deep-sea sediment cores taken from 4 different regions in the Japan Sea were subjected to analyses for 5 major and 11 trace elements by means of instrumental photon acti vation analysis with 30 MeV bremsstrahlung. These elements were Ca, Fe, Mg, Na, Ti, Ba, Ce, Co, C r, Mn, Nb, Ni, Rb, Sr, Y and Zr. Additionally, Al was determined spectrophotometrically, and Si02 contents of selected specimens were determined by a conventional chemical method. Variation patterns of these elements along the core columns were derived, and discussions were give on the results from a viewpoint of element stratigraphy. Sedimentation rate ? was determined on the basis of the stratigraphic change of planktonic formainiferal assemblages, and found to be 9, 10 and 20 cm/10³ y for 3 of the 4 cores. The Holocene-Pleistocene boundary for these cores wa8 determined to be 90, 110 and 210 cm beneath the ocean floor, respectively. Variations in concentrations of the elements in deposits of post-glacial age are relatively small. On the contrary, abundance distributions of the elements are generally inhomogeneous in glacial zones. Below the boundary levels, enrichments of Ca and Sr by biogeneous process were observed, and, especially for a core from Yamato Basin, these Ca maxima were well correlated with Mn maxima which would be the result of lateral migration of Mn during glaciations. Cobalt and Ni tend to be associated with Mn. Qne core taken around the Yamato Ridge was found to have no detectable foraminiferals, but seems to have an extremely slow deposition rate. Sedimentation would have occurred under very calm conditions, thereby causing remarkable enrichments of Mn, Fe, Co and Ni characteristic of pelagic sediments. In the central parts of the Japan Sea, the oxidized post-glacial zone appears to be a typical pelagic sediment.

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¹³C-NMR spectra of 2, 4-pentanedione [1] and 1-(p-substituted phenyl)-1, 3-butanediones [2]J and their cobalt(III) complexes [3], [4] were measured in benzene-d6 chloroform-d and DMSO-d6, solutions. The signals of [1] in these solvents were observed around 202, 58, 3Oppm for the Keto (K) form, and around 191, 100 and 25ppm for the enol (E) form. The signals of the K form disappeared, as the sample concentration is lowered. By cornplexation, the signals near 191 and 100 ppm for the E form shifted to the higher magnetic field side, while the signal near 25ppm, the lower magnetic field side. In chloroform-d, the signals due to the acetoacetyl group of [2] were observed around 193, 182, 96 and 25ppm for the E form. In DMSO-d₆, however, the signals for the K form were also observed around 53 and 3Oppm in addition to the signals for the E form. The ¹³C chemical shift of the acetoacetyl group for fac and mer isomers of [2] approximated to those for the E form of [2]. Each ¹³C of this group for the mer isomer was separated to the three signals with the difference of ±0.2 ppm. Linear relationships were found to exist between the 13C chemical shift for the acetoacetyl group of [2], [4] and Hammett parameters (δ_pp), Δ(the difference of chemical shift between both carbonyl carbons) of [2] and pK_d, and δof [4]and 10Dq.

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The analytical process of ortho-, pyro- and triphosphates of low concentration in water was investigated by the anion exchange chromatography using post-column method. The mixed solution prepared for ASTM D 515-72 without antimony potassium tartrate wcs used as a color-producing agent.
In the proposed method, the hydrolysis of conden sed phosphates in a PTFE-type valve loop injector as found to be avoided by the use of a stainless-steel-type one. Furthermore, the adsorption of colored molybdophosphate complex on the PTFE tube in the chromatographic system and the drift of its base line were found to be avoided by mixing the reaction mixture with sodium dodecyl sulfate solution at the outlet of the reaction bath.
The recommended conditions for analysis were as follows; column: 8 mm I. D. × 140 mm glass column, eluent: 0.25 mol·dm^-3 sodium chloride solution containing 1.5 mmol·dm^-3 EDTA, column temperature: 30°C, color-producing agent: above mentioned one, flow rate of eluent: 0.84 cm³· min^-1, flow rate of eluate from column delivered to detection system: 0.42 cm³min^-1, flow rate of color-prod-ucing agent: 0.21 cm³· min^-1, flow rate of 1.5% sodium dodecyl sulfate solution 0.16 ³· min^-1, reaction coil: 1 mm I. D. × 10 m, reaction bath temperature: 95°C, sample size: 2.0 cm.
The quantitative analysis of each condensed phosphate was attained by the proposed method and its detection limit was O.05 mg P. dm-3 for the measurement of peak area and 0.01 mg P. dm-3 for peak. height in chromatogram. This method was applied to various waters containing sewage and compared with ASTM method (D 515-72) for phosphorus in water (Table 3). The results obtained were satisfactory except for sea water.

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Previously we had reported an adsorption phenomenon which occured in the electric field applied liquid crystal (EF-LC) columns. However, any clear elucidation of the adsorption mechanism could not have been provided. Here, in order to study the mechanism further, the adsorption behaviour of series of ester and ketone homologues was investigated by using separation column-EF-LC column connecting modes. For all homologues, the relationships between carbon numbers and the adsorption amount showed U-shaped curves: The adsorption amount decreased first and showed minima, then it increased with increasing in the carbon numbers of solutes. The phenomena were discussed on the basis of the relation of the properties of liquid crystal with the structure of solute adsorbed. Then, the adsorption behaviour among the isomers of ketones and aldehydes was also studied. Their behaviour was compared with isomers of butanol, pentanol and butyl acetate which were described elsewhere. It was concluded that structural contribution, especially that from carbon skeleton, to the adsorption was independent of other factors such as types of functional group, the structure of liquid crystal molecule and so on. Therefore, if the carbon skeleton except functional group of the solute was the same, similar trends on the adsorption resulted.

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In the reaction of some iodoazoxybenzenes with 90% sulfuric acid and chlorosulfuric acid, the corresponding iodoazobenzenes were obtained as a main product. When azoxybenzene itself and 2, 2'-dihaloazoxybenzenes other than the diiodo compounds were treated with 90% sulfuric acid, the 4-hydroxyazobenzenes were obtained in more than 40% yield.2-Hydroxyazobenzenes were detected as a sole products under UV irradiation of iodoazoxybenzenes. Some iodoazoxybenzene-SbCl₅ (1: 1) complexes, were stable to thermolysis.

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5-Phenoxymethy1-2-oxazolidinone(PM0), its derivatives, and 5-phenylthiomethy1-2-oxazo lidinone(PTO) were prepared by the reaction of tris(2, 3-epoxypropyl) isocyanurate with various phenols and benzenethiol. The oxazolidinones were found by the thermal analysis to be thermally stable. Both DTA and DSC curves for these compounds except for PMO revealed a single endothermic peak in the vicinity of their melting points. Heat of fusion had the lowest value for PTO. The heat of fusion values of compounds containing the electronreleasing substituents was greater than those of the electron-attracting substituents for PMO derivatives (Table 2). The main fragmentation mechanism by electron impact for the linkages between the benzene and oxazolidinone rings was found to consist of two processes; simple cleavage ( I ) and rearrangement reaction(II). Further, each process had the three cleavage modes (Fig.4). The ( I )/( II) ratios for the intensities of the main fragment ions in mass spectra were 0.52in PMO and 1.13 in PTO. The base peak for most PMO derivatives was RC₆H₅O(Degree of unsaturation =4.0). The proportion of fragment ions containing the benzene ring in the main fragmentation was greater than 80% (Table 4).

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Primary and secondary acyclic β-nitroenamines were prepared and their structures were elucidated. N, N'-Bis(1-methyl-2-nitrovinyl) polymethyIenediamines [7]were obtained by the reaction of 3-nitro-2, 4-pentanedione. [2]with polymethylenediamines (n=2, 3, 4 and 6). Products [7](n =2) and [7](n =3) were allowed to react with transition metal( II ) acetate to give the corresponding metal(II) complexes C [8] (n =2) Cu, [8](n =2) Ni, [8](n =2) Co and [8] (n =3) Cu in good yield. The reaction of [2] with ammonia or primary amines in the presence of titanium (IV) chloride afforded the corresponding 4-(monosubstituted amino)-3-nitro3-penten-2-one [6] in 37-69.5% yield (substituent R: H, Me, PhCH2 and Ph). Nitroacetone C 33 reacted similarly to give the corresponding 2-(substituted amino)-1-nitropropene C [4]in 51.5 -91% yield. Based on the spectral data, [7] and 4 were concluded to be present entirely in the chelated structure of nitroenamine form NH ON and [6] were in the chelated structure of s3-aminoenone form NH…O=C.

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Hexane soluble part (oil) from Akabira coal-derived liquid was separated into 5 fractions of compound type using dual packed silica-alumina gel liquid chromatography (Fig.2). Neutral aromatic fractions, Fr-M, D, and T, which included aromatic compound with increasing aromatic ring number in that order, were further separated into 5 or 6 subfractions according to molecular size using GPC (Fig.3).
From the low voltage-low resolution mass spectrum of each fractions, the nominal Z values of respective ion peaks were decided directly by selecting m/z with each interval of 14 mass number. From the molecular weight distributions of nominal Z series (Fig.5), the true Z values were assigned as follows: ( 1 ) By LC separation, Fr-M, D and T were obtained, consisting mainly of monocyclic, dicyclic, and tri and/or tetracyclic aromatic hydrocarbons. ( 2 ) On bi-modal molecular weight distribution of the same nominal Z series, higher m/z distribution mode has 14 smaller Z number than the lower mode. ( 3 ) The minimum m/z of molecular weight distribution mode is the same or larger than the molecular weight of the corresponding aromatic-naphthenic parent ring system (Table 4).
The series of compound type with true Z values decided by the above methods were characterized by M_w-V_e (GPC) correlation (Fig.6). Components of the oil were shown as compound types and alkyl side chain carbon number distribution (Table 5). Aromatic compound type are distributed from Z=-12 to Z=-42, and showing a maximum at Z=-14. Alkyl side chain carbons range from 0 to 20, and having a maximum at 4 carbon atoms. t Chemical Structure of Coal-derived Liquids. I.

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The average structure of each component present in a coal-derived liquid was estimated by a mass spectrometric technique. Average structural parameters (carbon aromaticity: fa, ave-rage rage aromatic ring number: R_a, average naphthenic ring number: R_N, and average saturated. side chain carbon number: C_ss) were determined as the average chemical structure of the individual components identified by mass spectrometry (Table 2).
The values of the average chemical structural parameters by mass spectrometry show considerably good agreement with results obtained by the conventional NMR method (Table 3).

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A new class of surfactants, 3-(3-alkyl-2-oxoimidazolidine-1-yl)-1-propanesulfonic acids [1], were prepared in high yields by the N-sulfopropylation of 1-alkyl-2-imidazolidinones (Table 2) with 1, 3-propanesultone by use of sodium hydride as a base (Table 3). The sulfonic acid derivatives [1] had good surface-active properties; particularly, the C₁₂, C₁₄, and C₁₆ derivatives were as good as or superior to sodium dodecylbenzenesulfonate (DBS)in the solubilization of Orange OT in water (Fig.3) and in the emulsification of liquid para ffffin in water (Fig.2). They showed poor to moderate foaming ability and foam stability (Table 5). A linear relation was observed between the logarithm of the critical micelle concentration and the number of carbon atoms in the alkyl chain of [1]. The compounds were also tested for the antimicrobial activity against a gram -positive bacterium, Staphylococcus aureus, a gram-negative bacterium, Escherichia coli, and a fungus, Asper gillus oryzae. All the compounds were virtually ineffective against S. aureus and E. coli, but the C₁₄ and C₁₆ homologs had noticeable antifungal activity.

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In order to prepare N-(fluoroalkyl)anilines the reactions of the various fluoroalkyl areneand methanesulfonates with aniline were investigated. Sulfolane gave the best results among the solvents examined. N-(α, α, ω-Trihydroperfluoroalkyl) anilines ([8 b] and [8 c]), for example, could be prepared in sulfolane but not in other solvents (Table 1). Fluoroalkyl o-nitrobenzenesulfonates [6] proved to be a highly effective agent for N-fluoroalkylation of aniline in sulfolane (Tables 3 and 4). The reactions of N-ethylaniline with fluoroalkyl arenesulfonates in the same solvent led to ordinary N-fluoroalkylation, which was accompanied by the elimination of N-ethyl group and/or migration of the ethyl group to the para position to give the corresponding products (Scheme 3). The reactions of fluoroalkyl o-nitrobenzenesulfonates with N-(hydroxyethyl)aniline in sulfolane afforded N-hydroxyethyl-N-(fluoroalkyl)anilines in good yields.

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The effects of various urea derivatives on the carboxylation of fluorene with carbon dioxide were examined in the presence of potassium carbonate at room temperature under atmospheric pressure. As shown in Table 2, the carboxylation of fluorene was remakably promoted by the addition of 1, 3-diphenylurea (DPU).
Acetophenone, 1-indanone, indene, phenylacetonitrile, and 1-tetralone were effetively carboxylated by employing the similar reagent system, 1, 3-diphenylurea, potassium carbonate and carbon dioxide to produce benzoylacetic acid, 1-oxoindan-2-carboxylic acid, 1 H-indene3-carboxylic acid, a-cyanophenylacetic acid, and 1-oxo-1, 2, 3, 4-tetrahydro-2-naphthoic acid, respectively (Table 4). NMR and other investigations carried out in the carboxylation of fluorene led us to suggest that the carboxylation is initiated by the formation of a complex among 1, 3-diphenylurea, potassium carbonate and carbon dioxide (2: 1: 2), and the reaction of the complex with fluorene to form 9-fluorene carboxylate is the fast step. Rubidium carbonate and cesium carbonate proved to be better base than potassium carbonate, but l ithium carbonate and sodium carbonate were not effective (Table 3).

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The effect of bases and additives in the azide method were investigated on the yields in the fragment condensation on a soluble polymer support. The effects of them on the racemization and side reactions were also investigated. The amount of racemization was determined by the Izumiya method. Z-Gly-NHCH(CH₃)NHCO-Leu-OBzl [1], [Z-Gly-NHCH(CH₃)NH]₂CO [2], and Z-Gly-Ala-NH₂ [3] were synthesized by different methods and hydrogenated to obtain the standards for determination of the amounts of by-products by use of ion-exchange chromatography.
When triethylamine (TEA) was used as a base in 0-6 equivalent excess, increase in base contents increased the amount of recemization. On the other hand, N-methylmorphorine (NMM) was used as a base, no racemization occurred even in the case of 6 equivalent excess. Addition of 1-hydroxy-1 H-benzotriazole (HOBt) depressed the racemization fairly, and addition of N-hydroxysuccimide (HOSu) slightly. The amounts of by-products [ 1'] and [ 3'] were less in the case of TEA used as a base than that of NMM, regardless of an additive. The addition of HOBt and HOSu had no effect on side reactions. In the coupling reactions of BocAla-Gly-Ala-N₃, Boc-Ala₂-Leu₃-N₃, or Boc-Ala₂-Leu₃-Pro₂-Leu₃-N₃ with Leu or Ile bound to a soluble polymer support, almost quantitative yields were achieved by the use of TEA or NMM as a base in 6 equivalent excess and HOBt as an additive in 12 equivalent.

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The interactions of copper chlorophyll and copper chlorophyllin with various kinds of elect-ron acceptors have been investigated by means of measurements of longitudinal relaxation time (T₁) in ₁H-NMR spectra. The additions of copper chlorophyll to the solutions containing one of the electron acceptors shorten the T₁ values of the protons in the electron acceptors except β-carotene. These phenomena are considered to be due to the dipole-dipole interactions of the electron spins on Cu₂₊ and N atoms of four pyrrole units with the protons of the electron acceptors. The distances from the copper ion and the N atoms of pyrroles of copper chloro-phyll to the protons of each electron acceptor have been estimated by using the Solomon's equation. The structures of the complexes of copper chlorophyllin with the electron acceptors are proposed by means of computer simulation.

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In order to obtain a new pharmcologically active polymer, 1-aryl-5-(3-methoxy-4-hydroxyphenyl)2-oxopyrrolidine-4-carboxylic acid [2]and their methacrylates [3]were prepared. The ammonium salts of [2] and [3] were submitted to the antibacterial activity test to Bacillus polymyxa strain Hino using a modified Winogradsky's medium. Triethylammonium 5-[3-meththoxy-4-(methacryloyloxy)phenyI]-1-tolyl-2-oxopyrrolidine-4-carboxylate[7b] show-ed the highest antibacterial activity.

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In order to elucidate the catalysis of nitrogen monoxide reduction with ammonia, the changes in oxidation state by the reaction of vanadium supported on silica, titania, and titania coated-silica were studied by use of ESR spectroscopy. The catalysis of the vanadium oxide was found to be inherently correlated with the redox mechanism: V⁵⁺ was reduced by NO-NE3reaction to V⁴⁺ which was reoxidized by oxygen to V⁵⁺. The activity of the supported vanadium oxide was inferred to be mainly determined both by the amount of the effective vanadium ion shuttling between V⁵⁺ and V⁴⁺ and by the rate of the reoxidation of V⁴⁺ to V⁵⁺by oxygen. These two factors were markedly affected by the supports: with titania-supported catalyst the amount of the effective vanadium species was large and the rate of reoxidation of vanadium was high compared with the other two catalysts. The increase in the catalytic activity by treating the silica surface with titania was attributed to the increases both in the amount of the effective vanadium species and in the rate of reoxidation of vanadium.

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The polarogram of 4-isopropyltropolone (Hhi) using a dropping mercury electrode was observed and analysed. The first anodic wave was attributed to the adsorption wave, and the second wave was concluded to result in the electrode oxidation of the π-electron system accompanied by a follow-up chemical reaction; the formal potential corresponding to the following reaction was calculated to O.29 V vs. SCE,
Hhi →Ox^(n-1) + H⁺+ ne (n≤6) (1)
where Ox^(n-1) represents the oxidized form of 4-isopropyltropolone. In contrast with a dropping mercury electrode, the anodic wave of 4-isopropyltropolone obtained at a platinum electrode was resulted by the one-electron oxidation process accompanied by a follow-up chemical reaction.

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The reactions of aldehydes with nitromethane in the presence of a catalytic amount of nickel(II) acetate-2, 2'-bipyridine complex proceed at room temperature to give nitro alcohols in good yields.

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The reaction of 1, 1'-bis(methoxycarbonyl)divinylamine (BDA) with primary amines was investigated as an example of nucleophilic attack on a cross-conjugated dienamine. BDA reacted with primary amines to yield azomethines [5]-[8], which supported the reaction mechanism involving a nucleophilic attack of primary amines at the electron deficient α-carbon atom of the enamine form of BDA, followed by an elimination of methyl 2-aminoacrylate. In these reactions, unexpected 3-pyrrolin-2-ones [10]-[13]were also isolated and their structures were determined by means of IR and 1H-NMR spectra.

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Acetone azine, which gives hydrazine quantitatively on acid-hydrolysis, was obtained in a high yield from acetone and ammonia via hydrogen peroxide oxidation of the intermediate imine in the presence of benzonitrile. Attempts were made to apply the reaction to the syn-thesis of substituted hydrazones. Thus acetone phenylhydrazone was obtained accompanied with azine from acetone, ammonia and aniline. The yield of phenylhydrazone increased and that of azine decreased with increasing the aniline added. A large excess of aniline was unfavorable for preparation of both azine and hydrazone. Similar behavior was observed for t-butylamine to afford acetone t-butylhydrazone and azine, while cyclohexylamine resulted in the exclusive formation of 2-cyclohexyl-3, 3-dimethyloxaziridine.

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3', 4'-Bis(benzyloxy)-, 4'-benzyloxy-5, 6, 7, 8-tetramethoxy- and 3', 4', 6-tris(benzyloxy)-5, 7, 8-trimethoxyflavones, ([7a], [7b] and, [7c], respectively) were synthesized from the corres-ponding 2-hydroxyacetophenones and the substituted benzoyl chloride via 3 steps. The desired hydroxyflavones [3a-c], which could be inhibitors of lens aldose reductase, were obtained by the hydrogenolysis of benzyloxyflavones [7 a-c] followed by the selective demethylation with anhydrous aluminum chloride in acetonitrile. A natural flavone isolated from Sideritis leucantha Cavanilles was found to be identical with the title compound [3a].

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Radical graft polymerizations of styrene and methyl methacrylate onto 1, 4-polybutadiene were carried out in various solvents using α, α'-azobisisobutyronitrile as an initiator. Maxi-mum vaValues of grafting and grafting efficiency were observed in the solvent whose dielectric constant was similar to that of monomer.

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The mixture of sample and Cu²⁺ solutions was chromatographed with a Sephadex G-10 gel column using O.1 M (1 M=1 mol. dm^-3) Tris-HCl solution (pH 6.9) containing 10 ng/cm³ of Cu²⁺ as eluent solution. Copper complexes, e. g., Cu-EDTA complex, were eluted earlier than free Cu²⁺. Thus only complexed copper concentration, which was defined as "complexing capacity" could be determined accurately. Detection limit for complexing capacity with the present method was 0.3 μM. No apparent interferences with coexisting cations were observed. The present method was applied to the measurement of complexing capacity of lake water. Complexing capacity of freshwater in Lake Kasumigaura was determined to be 0.02 μM. The molecules with molecular weight more than 10000 was preconcentrated by an ultrafiltration technique.

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