Reductive amination of 4-t-butylcyclohexanone (1) and related compounds with platinum group metals has been studied in ethanolic ammonia solution at 50°C and 80kg/cm² H₂ pressure. Selectivities for the formation of 4-t-butylcyclohexylamine(2) and bis(4-t-butylcyclohexyl) amine(3) depend on the platinum group metals used as the catalyst. The yields of (2) increased in the order of Pt<Os<Ir<Pd<Rh<Ru and was between 59-97%.
The reaction of (1) over Pt gave (3) in as high as 34% yield, wher eas Ru did not produce (3) at all. (1) afforded cis-- (2) much more than trans- (2) over all the metals. The reaction route and the stereochemistry of the reductive amination of (1) were discussed on the basis of the formation and hydrogenation of intermediates such as 4-t-butylcyclohexaneimine(6) and Shiff's base, 4-t-butyl-N-(4-t-butylcyclohexylidene)cyclohexylamine(5). Conformation for (3) and (5) were also determined by ¹H-NMR.

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When a 8 wt% MoO₃/SiO₂ catalyst was leached with water or exposed to water vapor, molybdosilicic acid (one of heteropoly acids) in a Keggin structure was found to be formed using IR, UV-VIS diffuse reflectance, and ESR spectroscopic techniques. This molybdenum species showed an acidic property characteristic of heteropoly acid in IR spectrum of pyridine adsorbed on water-treated MoO₃/SiO₂, or in catalytic reactions of isomerization of 1-butene and dehydration of 2-propanol. Since MoO₃/SiO₂ catalyst is active in catalytic reactions containing water as one of reactants or products it was pointed out that water plays an important role to afford a new catalytically active species like molybdosilicic acid.

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Evaporation of liquid from a network of inter-connecting pores in porous solid is governed by the percolation mechanism. For this reason it is presumed that a supported component in the catalyst prepared by the impregnation and drying method aggregates much bigger than each pore in the carrier independent of the pore structure (black circles in Fig.1).
Graded amounts of salt-mixture (ZnCl₂/KCl) were supported on the carriers, al umina (ACBM-1) and silica (ID-gel). Adsorption isotherms of benzene were measured on the resulting catalysts. Dispersing configuration of the deposit in the pore texture was speculated from the variation in the pore size distribution of carriers with loading.
Values on the last column in Table 1, the sum of the volumes of salt and residual pores, were approximately constant and independent of the amount of salt, showing that all of the salt was obviously deposited in the pore texture.
In Fig.3 it is worth noting that melting of salt in the catalysts does not cause the change in its configuration. As the configuration is not affected with the drying rate of impregnant as well (Fig.4), the evaporation of impregnant is governed by a pseudo-equilibrium process.
Resemblance of pore size distribution between the observed curves in Figs. 7 and 8 and the theoretically calculated ones in Figs.10 and 11, respectively, supports that the percolation mechanism is applied to the drying of impregnant.

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Catalytic oxidation of ethanol to ethyl acetate was investigated over Mo-Sb-O mixed oxides. Combination of Mo0₃ with Sb₂0₄ resulted in improving catalytic activity for the formatipn of ethyl acetate and lowering temperature in comparison to the component oxides. Catalysis was unselective at the initial stage of ethanol oxidation, but the selectivity for ethyl acetate was greatly enhanced in the course of reaction. In the steady state, the Mo-Sb-O catalyst was in partially reduced state, which is expected to give rise to the formation of the mixed oxide of Mo-Sb-O. Of the three mixed oxide phases of the Mo-Sb-O system, Sb₂Mo₁₀O₃₁ (Y phase) was actiye for oxidative esterification of ethanol. This phase was less active for oxidative esterification of other alcohols. The oxidation to ethyl acetate is considered to proceed by 2 steps via formation of acetaldehyde.

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Solid solutions in the system barium fluorophlogopite (Ba_0.5Mg₃AlSi₃O₁₀F₂)-fluorotetrasilicic mica (KMg_2.5Si₄O₁₀F₂) were synthesized from melts. The resultant solid solutions were studied by X-ray diffractometry and their specific gravities and refractive indices were examined. A complete series of solid solution [Ba_0.5(1-x)K_xMg_3-0.5xAl_1-xSi_3+xO₁₀F₂] was obtained, where x is 0≤x≤1. Each interplanar spacing [(200), (060), (005)] changes continuously and linearly through the solid solution series, but the changing rates differ. That is, as the content of fluorotetrasilicic mica (TSM) increases, the d spacings of (200) and (060) decrease, their rates were 1.11 and 0.68%, respectively between the end members, whereas that of (005) increases with a rate of 1.26%. The specific gravities and refractive indices of the solid solution change linearly with the molar content maintaining the following equations: S. G=3.12-0.33y, and R. I=1.581-0.052y, where y is the mole fraction of TSM. All the d spacings increase linearly as the temperature is raised, but the degree of the increase depends on the chemical composition of solid solutions: the thermal expansion along a* direction decreases, whereas that of c* direction increases with increasing TSM content. The thermal expansion for b axis could not determined precisely since (331) peaks interfered with (060) peaks.

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In order to clarify the thermal property of fluorotetrasilicic mica (KMg_2.5Si₄O₁₀F₂), their thermal decomposition reactions in atmosphere were investigated by means of isothermogravimetric methods with specimens of large crystals and various grain sizes. X-ray diffractometry, scanning electorn microscopy and chemical analysis were used to examine the decomposition products.
Isothermal decomposition curves for each specimen (large crystal; 5 × 5 × 0.02 mm, 42-80mesh, 80-200 mesh and —325 mesh) at 1000-1100°C were all of the slowing-down type. The final weight loss value was 6.35% for each specimen, and the speed at which the final value was achieved becomes more rapid with decreased grain size and increased treating temperature.
The volatile component with thermal decomposition was mainly silicon tetrafluoride (SiF₄). The amount was 6.35%, determined in the same manner as used for the final weight loss value. The decomposition product was forsterite (Mg₂SiO₄); the amount was 35.0%. On the basis of these values, the reaction equation on the thermal decomposition of fluorotetrasilicic mica could be derived as follows:
KMg_2.5Si₄O₁₀F₂ → 0.25 SiF₄ + 1.0Mg₂SiO₄ + 1.0 amorphous matter (K-Mg-Si-O-F)
This reaction mechanism was best explained by the equation [F(α)=1-(1-α)¹/²=kt] which was based on a two-dimensional interface-controlled process. This suggests that the thermal decomposition reaction proceeded by the forward movement of the boundary between mother crystal and decomposition product. The apparent activation energy by the thermal decomposition was estimated to be 146 ± 16kJ/mol.

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Hydrogen reduction of NiO under constant hydrogen partial pressures was studied by using a thermobalance. The reduction is adopted as a reaction step of a thermochemical hydrogen production process of Ni-I-S system. The reduction curves show the typical S shape at temperatures ranging from 455 to 673 K and under hydrogen pressures from 5.1 to 101 kPa. The empirical reduction rate k_e was determined from the maximum slope of the reduction curve.
An abnormal behavior of k_e was found in a region of reduction temperature (transition region), where k_e deviates from the Arrhenius law (Figs.3, 4). The Arrhenius plots of k_e were found to be composed of two different straight lines below and above the transition region. It is shown that the result is due to existence of two different kinds of kinetics. These kinetic regions were determined experimentally in the reduction temperature and the hydrogen pressure (Fig.7). In region (L), where reduction temperature is lower than the transition region, the relation between the reduction rate ke and the hydrogen pressure P was represented by a Langmuir-type formula, P/k_e=1/ab + P/b. In region (F), where the temperature is higher than the transition region, the relation between k_e and P was represented by a Freundlich-type formula, in k_e=ln a + (1/n)ln P. The activation energy of hydrogen reduction of NiO was 98 ± 4 kJ⋅mol^-1 in region (L), and 69 ± 6 kJ⋅mol^-1 in region (F). It is concluded that the transition region in Fig.7 can not be related to the Neel temperature of NiO.

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Ni-Fe alloy layer was formed on the surface of a core iron particle and under the top of a coated silicic acid layer. Inhibition of growth of the iron crystallites by the silicic acid was suppressed by the Ni-Fe alloy layer. Coercivity of iron particles could markedly be decreased without changing the skeleton of acicular iron fine particles.

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The phase change and thermal decomposition of YBa₂Cu₃0_x under atmospheres of oxygen, air and nitrogen in the temperature range between room temperature and 1200°C were studied by thermogravimetry (TG) and liquid nitrogen quenching technique.
On heating, orthorhombic YBa₂Cu₃0_x to tetra gonal structure. At 790-970°C in air, a part of tetragonal YBa₂Cu₃0_x decomposed to BaCu0₂, but most of the tetragonal YBa₂Cu₃0_x remained stable. The formation of an inhomogeneous region of compos ition was caused by insufficient mixing of starting oxides and solid state reaction. A YBa₂Cu₃0_x sample containing large fluctuations of composition tends to decompose to BaCuO₂ in higher temperature.
By further heating, tetragonal YBa₂Cu₃0_x decomposed to YBa₂Cu₃0_x, BaCu0₂ and an unknown phase at 970°C. An unknown phase was observed in the sample quenched from 1100°C. It increased by 1 h heating at 1100°C and oozed to the surface of the sample during heating. The formation of unknown phase was dependent on the oxygen partial pressure and accelerated under lower oxygen pressure. The unknown phase was near in composition to Y: Ba: Cu=O.1 : 1 : 1. It was unstable in air and at room temperature.
The sequence of the thermal decomposition of YBa₂Cu₃0_x was almost the same in nitrogen, air and oxygen. The decomposition temperatures at each decomposition step decreased with decreasing oxygen partial pressure.

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From the polarographic behavior of copper(II), lead(II), cadmium (II) and manganese(II) ions in (1-hydroxyethylidene)bisphosphonic acid (HEBP, H₅L) solutions at an ionic strength of 0.4 mol⋅dm^-3 adjusted with sodium perchlorate, the compositions of the metal complexes and their stability constants were determined. The species of MH₃L, MH₂L^-, MHL^2-M(H₃L)₂^2-, M(H₃L)H₂L^3-, M(H₂L)₂^4- and M(H₂L)HL_5- for copper and manganese, and same species except MH₂L^- and MHL^2- for cadmium, were found in the pH ranges from 4.6 to 6.4. Species of MHL^2-, ML^3-, M(OH)L^4-, M(HL)₂^6- and ML₂^8- were found in the pH ranges from 11.5 to 12.9 for lead (II).The flotation of HEBP by complexing with iron (III) and the HEBP complexes was investigated in a cell (20 cm × 2.7 cm I. D.). Recover ies of 4.0 × 10^-4 mol⋅dm^-3 of HEBP and the HEBP omplexes of copper(II), lead(II) and manganese (II) were 99.6 %, and 99.6, 98.6 and 91.5%, respectively, by the flotation for ab out 5 min using (1.2-1.6) × 10^-3 mol⋅dm^-3 of dodecylammonium acetate (DAA) as a surfactant at the pH from 6.0 to 9.5. The presence of 6382 ppm of CI^-, 3840ppm of SO₄^2- and 3100 ppm of NO₃^- did not interfere the flotation. It seems that the flotation of HEBP and the complexes proceeds through the formation of ion pair R_nMH_iL, where, n=5-n-i, R and n denoting the cation of DAA and the charge of the metal, respectively.

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New capsule-type column packing materials (CAPCELL-C₁₈) were designed as a new hybrid type so as to combine advantages of silica-based packing materials with those of organic porous polymer beads.
CAPCELL-C₁₈ was obtained by following three steps, i. e., bringing silicone monomers in contact with the surface of totally porous silica gel (5μm, spherical, porediameter, 120Å), polymerizing them, and thereafter attaching the octadecyl group to the silicone polymer formed on the surface.
The CAPCELL-C₁₈, column packed by the slurry method was kept stable through the continuous operation for 550 and 300h under pH 9 and 10 conditions, respectively.
In the separation of homologous alkylbenzenes, alkyl benzoates and m-haloanilines, all the molecules eluted from the column according to their degree of hydrophobic constant (log P)which were calculated from the Rekker's value under alkaline conditions (pH=1O). Furthermore, in each homologue, linear relationships were also observed between log P and logarithm values of capacity factors under alkaline conditions (pH=1O). These results agreed well with the retention behaviour obtained using conventional octadecylsilylated silica gels (ODS-silica gels) under acid and neutral conditions.
In the case of ODS-silica gels, usually, basic compounds such as m-haloanilines and benzylamine are retained and separated by a complicated ion pair technique with an acidic mobile phase. However, in the case of CAPCELL-C₁₈, these basic compounds were effectively retained and separated by an ion-suppression technique with a basic mobile phase.

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As partly reported in our previous paper, all dimethine type merocyanines studied so far show bathochromic shifts in visible absorption bands when they isomerize into the cis form by light irradiation, whereas most cis isomers of polymethine dyes are expected to show hypsochromic shifts known as the ‘cis shifts’.
In this work, we reinvestigated the s pectral shifts of four types of merocyanines ( MD-CO, MD-CS, MD-SO and MD-SS ) in cyclohexane and acetonitrile. The magnitude of the shift was 15 - 23 nm in cyclohexane and 9 - 15 nm in acetonitrile. We also measured the oxidation potentials (E_ox) and reduction potentials (E_red) and their changes by isomerization. E_ox of the trans MD-CO was 0.362 V vs. Ag/AgNO₃ and that of cis was 0.34 V vs. Ag/AgNO₃. Ered' however, did not show any difference in the two isomers. For other merocyanines whose isomers could not be isolated because of their rapid thermal isomerization, we attempted to measure E_ox and E_red in photostationary states where the unstable photoisomers were expected to be enriched. The results were essentially the same as in the case of MD-CO, that is, E_ox's of cis forms were always more negative than those of trans but E_red's did not change at all in both forms. These facts suggest that the spectral shifts should be attributed to the elevation of the HOMO energy in the cis form rather than to the lowering of the LUMO energy.
Accord ing to theoretical considerations based on both Hückel MO and electrostatic interactions, we could explain such experimental phenomena in the following way. The oxygen atom comes very close to C_α in the cis form (2.79Å) while it goes apart in the trans (4.44Å). The oxygen is the most negatively charged atom. The AO of C_α is dominant in HOMO (16%) while it contributes little ( <2% ) in LUMO. Under such circumstances, it would be clear that the HOMO energy becomes higher in cis as a consequence of the repulsive interactions with the oxygen atom and that the LUMO energy is less sensitive to the conformational change.

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The Knoevenagel reactions of the various aldehydes with methyl acetoacetate and 2, 4-pentanedione as tautomers were carried out in the presence or absence of pyridine. The course of the reaction giving a β, γ-unsaturated compound was followed by the use of ¹H-NMR, and the signals of the intermediates and products were assigned. It would be favorable conditions for the selective formation of the β, γ-unsaturated compounds that an active methylene compound contains great high enol populations, and that further an aldehyde possesses conjugatable groups to a double bond formed. The reaction pathway proceeds in the sequence: addition → dehydration → rearrangement. In the presence of base catalyst the dehydration reaction proceeds via the keto-type intermediate to give β, γ-unsaturated compounds. In the absence of catalyst there may also exist the route through the enol (E)-type intermediate. It is thought that the rearrangement of double bond occurs via the enol-type β, γ-unsaturated compound to give the keto-type one.

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Reaction patheways of the ozonolysis of waste lignin discharged during the production of softwood pulp were examined through investigation of the ozonolysis of model compounds. The model compound consists of a 49: 51 (mol/mol) mixture of guaiacol and veratrole. The waste lignin in, water and the mixture of the model compounds in 50% aqueous dioxane were allowed to react with ozone at 30°C at pH 9. Aliquots from the reaction mixtures were withdrawn and determined for their absorbance at 280 nm, the formation of methoxyl, phenolic hydroxyl, muconic moieties, and also for the amounts of oxalic acid and its esters. The time profiles of the measured quantities showed good correlation between the waste lignin and its model compounds, except for the formation of methyl hydrogen oxalate from the model compounds.

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Six kinds of unsaturated polyesters were synthesized in the absence of catalyst by a process of simultaneous charge of endo-dicyclopentadiene with the other raw materials and by a dropwise charge of endo-dicyclopentadiene in the course of polyesterificataion. The component variations of the produced polyesters owing to the difference of charging process were investigated by ¹H-NMR spectroscopy.
In the case of the one-step method, an addition reaction of dicyclopentadiene with the terminal fumaric carboxyl groups mainly took place accompanying about 72 mol% endo-exo rearrangement of dicyclopentadiene. It was supposed that the addition may be directed to C 5-position carbon of exo-dicyclopentadiene and the steric configuration of these substituents may be exo-form. On the other hand, in the case of the dropwise method, almost all dicyclopentadiene thermally dissociated to cyclopentadiene, which transformed into trans-5-norbornene-2, 3-dicarboxylic acid skeleton on polyester main chains by the Diels-Alder reaction of cyclopentadiene with fumaric acid moiety of the polyester. The molecular structure of the produced polyesters was discussed.

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The polymerization of methyl methacrylate (MMA) initiated by hydridocarbonyltris(triphenylphosphine)rhodium(I) (hydridorhodium complex)-polyamine-carbon tetrachloride (CCl₄) was studied. The effect of polyamines on the polymerization of MMA generated by the initiator were studied and the polymerization activity was found to decrease in the following order:
Tetraethy lenepentamine>Triethylenetetramine>Diethylenetriamine>Ethylenediamine
In these initiator systems, the concentration of CCl₄ had a great influence on the yields of polymers, and the highest yields of the polymer were achieved when the molar ratio of [CCl₄]/[Hydridorhodium complex] was about 0.3.
When tetraethylenepentamine was used as a poly amine, the apparent overall activation energy for the MMA polymerization by the initiator was determined to be 6.3 kcal/mol. The composition curve of the copolymerization of styrene with MMA by the use of the initiator agrees well with that of the radical polymerization. Hence, it has been concluded that the polymerization of MMA by this system proceeds through a free radical mechanism,

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The accumulation of arsenic in Dunaliella sp. has been studied with respect to environmental factors such as pH, temperature, NaCl concentration and light intensity, in order to determine the optimal conditions for arsenic recovery. The accumulated amount of arsenic in Dunaliella sp. was measured as a function of time in a solution containing 10mg As(V)l by DDTC-Ag/pyridine method at batch procedure. It was found that the amount of arsenic depended greatly on the environmental factors, and further varied considerably with time under given conditions, showing a maximum value at a certain time. The optimal conditions under which Dunaliella sp. accumulated arsenic most, was pH 9, 20°C, about 20g NaCl⋅l^-1 and 4000 lux for the environmental factors described above, respectively. On the bases of the results obtained, it was suggested that the accumulation of arsenic in Dunaliella sp. was related to a metabolic activity caused by photosynthesis.

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Adsorption isotherms of several nonionic polymers, such as polyethylene glycol (PEG), polyacrylamide (PAA), poly(vinyl alcohol) (PVA), on five montmorillonites were obtained, and the effects of exchangable cations and physical properties of the montmorillonites as well as the effects of molecular weights and polarities of the adsorbates were investigated. For these nonionic polymers, montmorillonites showed quite high adsorption capacities which are near or over these on activated carbon.
The montmorillonite-Na and the bentonite I -Na showed greater adsorption capacities for high-inorganicity (hydrophilic) polymers, but the bentonite II-Ca, the acid clay, and the activated clay as well as activated carbon showed larger adsorption capacities for lowinorganicity (hydrophobic) polymers.
The basal spacings of the montmorillonite-Na increased 6.8Å. and 8.6Å by the adsorption of PEG and PVA, respectively. On the other hand, the basal spacing of the bentonite II-Ca did not increase by the adsorption.

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The adsorption behavior of mercury(II) onto granualar activated carbon was investigated by the batch method. After shaking for 17 h, the amounts of mercury in solution, on the activated carbon, and in precipitate were determined. The mercury concentration in solution revealed a minimum value below 10% in the pH 4-5 region (Fig.1). The activated carbon adsorbed 40-50% of mercury at acidic region and 15-20% at basic region (Fig.2). The amount of mercury adsorbed on the activated carbon did not agree with the amount of mercury lost from the solution (Fig.3). Twenty to thirty percent of mercury was contained in the precipitate over the range of pH from 3 to 10 and the loss of mercury was 2O-40% at pH below 10 (Fig.4). In the presence of EDTA, precipitation and loss of mercury were not observed (Fig.5). The proportion of Hg⁰ to the total mercury adsorbed on the granular activated carbon was slight when mercury was adsorbed at pH 2. If mercury was adsorbed at pH 7, a certain amount of Hg⁰ was observed on Mitsui activated carbon but Hg⁰was scarcely adsorbed on Takeda and Mitsubishi activated carbon (Fig.7). On the other hand, almost all of the mercury in the precipitate was Hg⁰ at pH 7 but Hg⁰ was scarcely contained in the precipitate at pH 2 (Fig.8). These results indicate that the reduction of mercury(II) by activated carbon results in precipitation and loss of Hg⁰ at neutral region.

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The hydrogenation of 1, 3-butadiene was carried out over four kinds of MgO catalysts at 50°C in a closed circulation apparatus. The catalysts used in this study were MgO( I ) offered from Catalysis Society of Japan, MgO(II) prepared by calcination of Mg(OH)₂ which was obtained by the hydration of MgO( I ), MgO(III) prepared from MgO( I )+NaOH(aq) and MgO(IV) prepared from MgO( I )+NaN₃. The reaction products were butenes and butan es could not be detected. MgO( I ) did not show any activity to the hydrogenation and MgO(II) did only slight activity. By the addition of sodium compounds the hydrogenation activity remarkably increased (Fig.1). As the reaction proceeded the ratio of cis- to trans-2-butene decreased with the isomerization from cis- to trans-2-butene (Fig.2). The activity of the hydrogenation is related to the basic site of MgO with an H-larger than 26.5. The selectivity of 2-butene formation was enhanced with the increase of basicity of MgO catalysts (Table 1).

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A gas chromatographic system has been developed for the measurement of impurities in oxygen such as methane, carbon monoxide, carbon dioxide, ethane, and acetylene. The seperation was performed on a Porapak Q, a Porapak N, and a Molecular Sieve 5 A. Oxygen eluted from a Molecular Sieve 5 A column was eliminated by passing through a column containing a deoxo catalyst. All impurities, after carbon monoxide and carbon dioxide were converted to methane by a methanizer, were determined by a FID.
The system was sensitive with a lower limit of about O.1 ppm.

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A new method for the preparation of (Z)-4-alkylidenebutenolides is described. Coupling reaction of acetylenic stannanes with enol triflates of β-keto esters gave the corres ponding (Z)-2-alken-4-ynoates which were hydrolyzed and then subjected to cyclization in the presence of HgO to give moderate yields of (Z)-4-alkylidenebutenolides.

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A zeolite catalyst showed high hydrocracking activity in a two stage upgrading process of coal-derived distillate. However, the zeolite was easily poisoned by the adsorption of heterocyclic compounds such as quinolines and carbazoles present in coal-derived light oil and lost its catalytic activity considerably. The removal of the heterocyclic compounds before hydrocracking was carried out by a combination of acid and base treatments, followed by washing of salts. Incorporated treatment of coal-derived distillate with acid in the two stage hydroprocessing resulted in the great increase of gasoline yield in the products.

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