In the sol-gel method, a homogeneous solution containing metal alkoxi des, other organic metal compounds or inorganic metal compounds is prepared. The solution is gelled by the hydrolysis and polycondensation of the compounds in the solution and the gel is converted to the aimed oxide glass or ceramics by heating it up to certain high temperatures. This method produces glasses and ceramics at much lower temperatures than the conventional method does, especially when the metal alkoxides are used as starting materials. In this review paper, the outline of the sol-gel method is presented at first. Then, the direct preparation of bulk bodies and fibers of silica will be described in detail, in which the shapes are formed as gel and then are converted to glass or ceramics without the change of shape.

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As reported previously, a polymerized butyl titanate (BT) in an organic solvent such as tetrahydrofuran yields a material which can be excited by visible light to give a characteristic ESR absorption. In the present work, addition of p-phenylenediamine (PD), N, N-dimethylpphenylenediamine (DMPD), or N, N, N′, N′-tetramethyl-p-phenylenediamine (TMPD) has been tried to get composite BT polymers. The TMPD-added BT polymer gives an ESR absorption under the illumination with visible light. The peak positions of this ESR absorption spectrum coincide well with those of the simulated ESR spectrum of TMPD^.+ under the assumption of a free motion of the cation, but a difference is seen with regard to the line width and relative peak intensity. Probably this is because the TMPD^.+ trapped in the polymer does not have such freedom of motion. The formation/decay of this TMPD radical cation is reversible. These results show that the positive charge in BT polymer generated by visible light is trapped by TMPD molecule which is coordinated to one of the Ti atoms to form TMPD^.+. Therefore, the counter charge, e^-, will be more stabilized in this polymer than in a neat BT polymer. The present material could be used as a light-to-electric energy conversion device.

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Pyridine appears to be an interesting solvent for quantitative analysis of weak acids, but systematic studies concerning the dissociation mechanism of acid in this solvent have not yet been attempted. In the present paper, the thermodynamic dissociation constants of simple ion pair K(HA) and the formation constants of homoconjugate ion K(HA₂^-) have been determined by measuring the conductivity of nitrophenols and the solubility of the corresponding potassium salts in the presence of acids in pyridine.
The limiting molar conductivity of pyridi nium ion λ^∞(PyH⁺) must be known in order to clarify the dissociation equilibria of acid in pyridine. The value of λ^∞(PyH⁺) at 25°C in pyridine was calculated to be 43.72 S·cm²·mol^-1 from the conductometric data of pyridinium and tetrabutylammonium perchlorates (Table 1), in addition to the previous datum (λ^∞(Bu₄N⁺)=21.87 S·cm²·mol^-1). The limiting molar conductivity of the homoconjugate ion was estimated on the basis of the conductivity of tetrabutylammonium m-nitrophenolate in acid solutions (Table 2). The values of K(HA₂^-) were determined by using the solubility data of potassium nitrophenolates in acid solutions and electrolytic conductivities of these saturated solutions. The dissociation constants K(HA) were determined from the conductometric data of nitrophenols and K(HA₂^-) values (Table 7).
It was found that ( 1 ) K(HA) of nitrophenol becom es larger with an increase in the number of substituent groups, ( 2 ) the order of acid strength is picric acid>2, 4-dinitrophenol(2, 4-DNP) >2, 6-DNP >2, 5-DNP, and p-nitrophenol(p-NP)> ο-NP> m-NP, ( 3 ) the substitution of the nitro group at meta position depresses the dissociation of acid, while enhances the formation of the homoconjugate ions, and ( 4 ) picric acid, 2, 4-DNP and 2, 6-DNP are hardly homoconjugated.

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The function of polyelectrolytes (polymers) to inhibit CaCO₃ scale deposition explained in a previous paper was thoroughly examined using solutions with various pHs and a number of polymers with different molecular weights and chemical compositions. Polymers used were nine polyacrylates (PAA) having mole cular weight of 600-25000, five acrylate/2-hydroxy-3-allyloxy-1-propanesulfonate copolymers (AA/HAPS) with molecu lar weight of 3000, and four acrylate/3-allyloxy-1, 2-propanediol copolymers (AAJAPDO) with molecular weight of 3000.
As pointed out prev iously, the inhibiting ability of polymers increases with its chelation affinity to Ca²⁺ ion but decreases when the chelation affinity excessively increases to facilitate the gelation. The maximum inhibition was obtained in a certain intermediate range of molecular weight for PAA, and at a suitable AA mole fraction for AA/HAPS and AA/APDO copolymers. The inhibition efficiency decreases with an increase of solution pH, probably because the degree of supersaturation of CaCO₃ is higher with higher pHs. For all the polymers, a simple common relationship between the inhibiting ability of polymer for CaCO₃deposition and its chelation affinity is obtained.
For all the gels, it was found that Ca²⁺ ion is contained in the gels and the mole ratio of Ca²⁺ ion and COO^- group is always 1/2. This result indicates that the gelation results from the formation of zero-charge polymer complexes by the reaction with Ca²⁺ ion.

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Mn-based perovskite-type oxides, La₁__xA′_xMnO₃ (A′=Ca, Sr, Ba), were prepared by calcining the amorphous citrate complex precursors (citrate process) and their catalytic activities for methane oxidation reaction were examined. It was found that the amorphous citrate precursors underwent thermal decomposition stepwise before perovskite-type oxides were obtained and that the final (third) decomposition step occurring at 550-650°C induced the crystallization of perovskite-type oxides (Figs.1, 2). Although the lowest temperature and the composition range for the perovskite formation were differed by A′ cations, well-crystallized perovskite-type oxides could be synthesized as single-phase compounds at temperatures as low as 550-650°C by the citrate process (Table 1). It is noted that the citrate process can adopt calcination temperature which is 200-300°C lower than the conventional acetate process. The specific surface area of oxide prepared by the citrate process reached a maximum, which was 4-6 times larger than that of the oxide prepared by acetate process, when calcined at the minimum temperature for single-phase perovskite formation (Table 2). With an increase in the calcination temperature, however, the specific surface area decreased monotonously and became almost equal to that of the oxide prepared by the acetate process at the calcination temperature of 850°C (Fig.3).
The specific catalytic activ ity per unit surface area of La_0.8Sr_0.2MnO₃ increased with an increase in calcination temperature (Fig.5) and, as far as a single-phase perovskite-type oxide was formed, it hardly depended on the preparation methods if the same calcination temperature was applied (Fig.6). When normalized to unit weight of catalysts, however, oxides calcined at lower temperature were more active than a supported Pt catalyst as well as La_0.8Sr_0.2CoO₃ and La_0.2Sr_0.8MnO₃ prepared by the acetate process (Fig. 6). It was concluded that the citrate process was very promising for preparing perovskite-type oxide catalysts having excellent activity (Fig.7) and thermal stability (Fig.8) at 600-700°C.

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Vapor-phase carbonylation of dimethyl ether(DME) to methyl acetate with nickel/active carbon catalyst was carried out in the presence of methyl iodide (Mel) promoter. The reaction was studied using a continuous-flow reactor with a fixed catalyst bed under the conditions of 200-300°C and 10-40 atm.
Methyl acetate was form ed with a selectivity more than 90% along with small amounts of acetic acid, acetic anhydride and methane. The catalyst with 2.5 wt% nickel gave the best yield of methyl acetate (Fig.1). Figure 2 and 3 show that the primary product of carbonylation is methyl acetate while acetic acid and acetic anhydride and formed succeedingly. The increase of reaction temperature and pressure resulted in an increase of the yield of methyl acetate and a decrease of the selectivity. However, with increasing of the MeI/DME ratio, both the yield and selectivity were increased (Fig.7).
The experimental rate equation was determined in a differential type reactor as follows (Fig.8):_??_
The dependency of the rate of DME carbonylation on the p artial pressure of methyl iodide was higher than that of methanol carbonylation and the rate of DME carbonylation was slower than methanol carbonylation. The important difference between the reactions of DME and MeOH is that the former reaction proceeds in a water-free system.
These observations suggest that the step of MeI adsorption is slow in DME carbonylation and water accelerates the step of MeI adsorption. In fact, introduction of water to DME carbonylation increased the reaction rate (Fig.9) and the selectivity of acetic acid (Fig.3). It is also presumed that water decomposes the methyl acetate which retards the carbonylation due to its strong adsorption.

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8-Quinolinethiol exhibits intense fluorescence in concentrated acids at an ordinary temperature, but this fluorescence is quenched by addition of water. In order to clear this mechanism, its excited singlet state properties in concentrated sulfuric or perchloric acid have been studied. Absorption and fluorescence spectra, prototropic equilibrium constants between cation and zwitterion, fluorescence quantum yields, fluorescence lifetimes and fluorescence polarization spectra were investigated.
With decreasing concentra tion of acids, the maxima in absorption and fluorescence spectra of 8-quinolinethiol were shifted to longer wavelength, and the quantum yield and the lifetime of the fluorescence were diminished. From the results obtained, the fluorescence of 8quinolinethiol in concentrated acid has been attributed to an exhibition of π-π^* transition due to protonation of quinoline nitrogen and to an inhibition of n-π^* transition.

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The Fries rearrangement of ο-tolyl phenylacetate[1] with anhydride aluminium chloride in boiling chlorobenzene gave 4-hydroxy-3-methylphenyl benzyl ketone [8] (58.0%) together with a small amount of 2-hydroxy-3-methylphenyl benzyl ketone [9]. The reverse Fries rearrangement of [9] into [1] with the same catalyst took place more readily than the conversion from [8] to [1], to which the low ortho-para ratio ([9]/[8]) in the Fries rearrangement of [1] seems to be ascribable (Fig.1, Table 1 and 4).
The yield of 2-hydroxy-4-methylphenyl benzyl ketone [15] from m-tolyl phenylacetate [2] in boiling nitromethane increased with the reaction time, while that of 4-hydroxy-2methylphenyl benzyl ketone [16] [decreased in a reverse manner during the reaction of[2]]. Consequently, the high ortho-para ratio ([15]/[16] =15.3) was obtained after 3-hours' reaction (Fig.2 and Table 2).
The yield of 4-hydrox y-3, 5-dimethylphenyl benzyl ketone [13] from 2, 6-xylyl phenylacetate [5] was higher than those of 2-hydroxy-3, 5-dimethylphenyl benzyl ketone [14] and 2hydroxy-5-methylphenyl benzyl ketone [17] from 2, 4-xylyl phenylacetate [4] and p-tolyl phenylacetate [3], respectively, under the same conditions. Those results seem to indicate that a rate of p-migration is faster than that of ortho-migration in the AlCl₃-catalyzed Fries rearrangement of tolyl phenylacetate (Table 3).
When [4] and [5] were boiled with AlCl₃ in toluene, respectively, the yield of [14] and [15] reduced and 2-tolyl benzyl ketone [6] and 4-tolyl benzyl ketone [7] were obtained in each case (Table 3). Considering the remarkable difference of the yields in the tolyl ketones and product ratio ([6]: 7.0% and [7]: 4.1% derived from [4], [6]/[7] =1.71. [6]: 3.8% and [7]: 47.2 % derived from [5], [6]/[7] =0.08), the para-rearrangement seems to proceed via an intermolecular migration and the ortho-migration occurs in an intramolecular manner.

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Oxidation of phenylhydrazine with aqueous solution of sodium periodate in the presence of eleven kinds of simple aliphatic alcohols was investigated at 40±1°C.1-Phenyl-1, 2, 4triazole(1.0%) was obtained in Me0H and 3, 5-dirnethy1-1-phenyl-1, 2, 4-triazole(0.5%) in EtOH. The new phenylazo-substituted alcohols were also obtained in i-BuOH, i-C₅H₁₁OH, 2-pentanol, 4-methyl-1-pentanol and 4-methyl-2-pentanol (Table 1).3, 5-Dimethy1-1phenyl-1, 2, 4-triazole was also obtained by using acetaldehyde phenylhydrazone instead of EtOH under the above reaction conditions and a reaction of acetaldehyde phenylhydrazone with benzoyl peroxide in MeOH gave the same product (Scheme 2). The reaction route leading to each product was conceivably summarized as shown in Schemes 3 and 4.

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The effects of reactor material, coexisting metal and reaction conditions on the oxidation of acetate to oxalate have been studied to clarify the mechanism of oxidation of coal in alkaline solutions and to improve the yield of oxalate. The yield of oxalate was greatly affected by the reactor material and coexisting metal, and the rate of oxidation of oxalate in a Ni reactor was as follows: Cu>Co>Ni>Mn>Cr>Fe. Two reaction mechanisms were considered from the yield ratio of oxalate/CO₂: consecutived oxidation of acetate to CO₂ via oxalate by Fe or Fe₂O₃ and the direct oxidation of acetate to CO₂ by Co and Mn. In the presence of Fe or Fe₂O₃ in a Ni reactor, the yield of oxalate increased remarkably as a result of lowering of the rate of oxidation of oxalate more than that of acetate. In addition, the yield of oxalate greatly increased with an increasing concentration of NaOH since hydroxide ion accelerated the rate of oxidation of acetate, but had little effect on the rate of oxidation of oxalate.

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The oxidation of trans-decahydronaphthalene [1] was carried out in acetic anhydride with oxygen in the presence of transition metal salts and bromide.
The oxidation of [1] in acetic anhydride proceeded much more rapidly than that in acetic acid. The most active catalyst system was Co-Ce-NH₄Br. The proper range of Ce/Co ratio, Br/Me ratio(Me=Co+Ce), and total metal concentration were 0.005-1.0, 1.0-2.0, and 3.5-7.0x10^-2 (mol/l), respectively.
The main componen t of monosubstituted oxidation products of [1] was 2-substituted calones. Decahydronaphthyl acetates [2] were formed by the oxidation of [1] in acetic anhydride by one step and the selectivity of [2] was above 80 mol% at 120°C.
In addition, relative reactivities of hydrogen atoms of [1] were determined at temperatures from 90 to 120°C.

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The components of the neutral nonpolar fraction of the coal-derived heavy oil were analyzed in detail and carcinogenic components were determined quantitatively.
The heavy distillate (bp 340-400°C) of the solvent-trea ted coal was separated into neutral (86.0%), acidic (6.4%) and basic fractions (2.2%). The neutral fraction was devide d into seven fractions using dual-packed liquid chromatography (Fig.1). Nonpolar fractions (Fr 1-6)were analyzed by a new techniq4e combining capillary GC-MS, retention index (RI) for capillary GC and HPLC-fluorescence methods. The methods were effective for identification of isomeric polycyclic aromatic hydrocarbons (PAHs) and their quantities were determined by capillary GC.
Components more than 95.5 % of the neutral fraction were identified. Normal paraffins (C₁₇-C₃₄), mono-, di-, tri- and tetracyclicnaphthene nonpolar (C₁₂-C₁₉) and thirty a romatic ring systems ranging from monocyclic to hexacyclic rings were identified (Table 2 and 4-6). The components were increased in the order of normal paraffins (17.2% in the neutral fraction) >C₀-C₄--substituted phenanthrene (12.8%) >C₀-C₄ pyrene (11.1%)>C₁-C₆ acenaphthene(7.2%) >C₀-C₄ 4, 5-dihydropyrene (5.9%) >C₀-C₆ fluorene(4.7%) >C₀-C₄ benzofluorene (three isomers, 4, 5%) >C₀-C₄ chrysene(3.0%).
Carcinogenic components such as chrysene, benz[a]anthracene, benzo[a]pyrene and dibenz [a, h]anthracene systems were concentrated in Fr 6 and constitute 3.3% of the neutral fraction (Table 7).

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Thermal decomposition reactions of trans-limonene-1, 2-oxide [1], 1, 2-epoxy-3-p-menthene [2], 1, 2-epoxy-4-p-menthene [3], 2-pinene oxide [4] and 2(10)-pinene oxide [5] were carried out in ZnCl₂/KCl/NaCl fused salts (chloride fused salts) or NaNO₂/NaNO₃/KNO₃ fused salts (nitrate fused salts). In the chloride fused salts, neo- and isodihydrocarvone [7] and [8] were obtained as the two main products from [1]. Under particular conditions, the ratio of [7] to [8] was 2: 3. α-Campholenaldehyde [18] and pinocarvone [19] were obtained from [4] as the two main products, amounting to more than 97% of the thermal decomposition products. Myrtanal [21] was obtained as the principal component from [5]with the 70% selectivity.

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The functional form for the temperature(T) dependence of the cholesteric pitch(P) of poly (γ-benzyl L-glutamate) (PBLG) was experimentally investigated, being compared with the results which have previously been reported in some literatures. The solvents used in this study were benzyl alcohol, N, N-dimethylformamide, m-cresol and 1, 4-dioxane. Concentration of PBLG was determined to 16.5 volume percent. A particular causion was paid for obtaining the value of time-independent pitch. Three functional forms were assumed for the analysis of the experimental data obtained.
We found it difficult to determine the P-T relationship over the entire range measured (Figs.4 and 5). At the temperatures above B-point where biphasic region is found at first and below C-point where gel phase disappeares, we assumed that the P-T relationship was distinct from that in anisotropic single phase (liquid crystal one in Fig.6). Therefore our discussion in this paper was limited only to the anisotropic single phase. In the four kinds of solutions studied here, a linear increase was not observed in the pitch P with increasing temperature (Fig.3), while both plots of 1/P vs. T(Fig.4) and 1/P vs.1/T(Fig.5) seem linear at first sight in the range mentioned above. We calculate the standard deviation from the straight line obtained by the least-squares method.
From the result, it was concluded that t he reciprocal pitch 1/P corresponding to the cholesteric twist angle was linear against 1/T rather than T in the variety of solvents. The result agreeds exactly with the temperature-dependent term of 1/P in the Kimura's theory on the cholesteric liquid crystals of polypeptide taking into account the effects of molecular exclusion and of attractive intermolecular force.

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On the conventional polymerization of Nylon 6, excess water is evaporated at the degassing stage from the reaction product which is already well-polymerized towards polymerization equilibrium. For the high-molecular-weight polymer, the degassing does not proceed always smoothly, because of high melt viscosity of the product at the degassing stage.
Then, production of high-molecular-weight polymer using prepolymeriza tion process has been studied, in which the degassing takes place from the prepolymer with lower melt viscosity.
First, prepolymer range which leads to polymer even after the degassing is determined through batchwise experiment (Fig.3). Then, in continuous polymerization, in fluence of prepolymer condition and degassing temperature on relative viscosity of polymer has been tested (Fig.6).
Meanwhile, solidification point is found to be a practical parameter to characterize the prepolymer and melt viscosity of the prepolymer is measured.
Melt viscosity of the prepolymer is about 50 poise at 240°C and increases rapidly as it approaches to the polymer in equilibrium (Fig.7).
Optimum prepolymer condition at the degassing stage is determined by experiment to be 170-175°C of solidification point. This corresponds to the prepolymer range where melt viscosity is still low and polymerization reaction has sufficiently proceeded, Under these conditions smooth and flash vaporization of water from the prepolymer at the degassing stage is observed. Thus the steady production of high-molecular-weight Nylon 6 can be proved.

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Superhigh-molecular-weight Nylon is required for extrusion of film, rod, etc., which can not be produced through melt polymerization. Solid polymerization of Nylon 66 pellet has been studied under the condition of heating temperatures of 210-460°C in vacuum from the view points of production of such superhigh-molecular-weight polymer and of the possible heterogenuity of molecular weight caused by solid phase reaction.
Relative viscosity of the polymer increases linearly with heating time (Fig.3) and apparent activation energy of 26 kcal/mol is calculated. Polymer with relative viscosity of 500 or more (mol. wt. of 100000 or more) can be produced without difficulty. By remelting the polymer which is obtained at higher temperatures (≥200°C) shows decrease of relative viscosity, while relative viscosity increases in the polymer yielded at lower temperature (Table 2). Polycondensation equilibrium constant drops as temperature increases, i. e., relative viscosity of the polymer in equilibrium of solid polymerization shall decrease by remelting. Experimental result shows that the polycondensation reaction is behind the speedy drying of the pellet at lower temperature and becomes to follow the drying at higher temperature.
Relative viscosity distribution in the radius direction of pellet, test rod with 15 mm diameter and commercial extruded rods has been measured. All of the commercial rods have higher relative viscosity in the central part than the surface (Table 4). The test rod after solid polymerization of 170°C, 60 h shows similar viscosity distribution.
However, the test rods polymerized at 210°C show higher value both in central part and outer surface (Fig.5). These distribution may be caused by slow heat transfer at the beginning of heat-up and at cool-down. Such viscosity distribution cannot be observed in the industrial pellet (Table 3).

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The reactions of 7/3 mixture of pyrene/phenanthrene in molar ratio (Aro) and dimethyl derivatives of benzenedimethanols (Aro) with p-tolnenesulfonic acid (PTS) were successfully carried out each polycondensed fused-polynuclear aromatics (COPNA) resin (DM series).
DMs used are two kinds of 2, 4 -dimethy1-1, 5-benzenedimethanol (DMMXG) and 2, 5-dimethyl1, 4-benzenedimethanol (DMPXG).
Reaction rates for the prep aration and some properties of resulting resins were discussed by comparing the results obtained for DM series with those of PXG series, which resins linked with PXG as reported previously, at the same conditions.
The DM/Aro (0.75-2.00 in molar ratio) mixtures we re heated with PTS (0.5-5.0 wt% in the mixtures) at 120°C in a stream of argon.
Reaction rates for the preparation wit h DM were faster than reaction rates with PXG, of course depending on reaction temperature, amount of PTS and molar ratio of DM/Aro.
The optimum conditions proposed for the preparation of B stage resins are as follows; DM/Aro: 1.25, PTS: 3 wt%, reaction temperature: 120°C, reaction period: 15-48 min.
At the same conditions, the reaction period for PXG is 33 min.
According to IR, NMR and UV spectra of the products, the reaction mechanism of DMCOPNA resins were noted to be equal to that of PXG-resins.
The resulting resins, even after post-cured, are more brittle and decompose thermally at ca.470°C lower than that of PXG series (490°C).
On the other hand, more attractive possibility of spinning fiber was observed in preparing B stage resin of DM series.
The distinction betw een DM and PXG stated above seems to be attributed to the electronreleasing effect and steric effect of two bulk methyl groups in DM.

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Sludges formed in the ferrite process from aqueous solutions containing various amounts of Ni²⁺, Cr³⁺ and Cr(Vi) were characterized by means of X-ray diffraction, TG-DTA and SEM-EDX analysis. The sludges formed from the solutions containing low concentration of the heavy metals had the structure of spinels. When O.1 moll/ solution of iron(II) sulfate was used, only spinel type sludge was produced from the starting solution containing Ni²⁺ below 3000 ppm, which corresponded to the atomic ratio of Ni/Fe =0.51. This concentration is almost equivalent to stoichiometric NiFe₂O₄ spinel. Above this concentration, Na₂Ni(SO₄)₂ was also formed. In the case of Cr³⁺ and Cr(VI) ions, the maxim um concentrations of Cr³⁺ and Cr(VI) ions for exclusive formation of spinel type sludge were limited to 1500 and 1000 ppm, which corresponded to the atomic ratios of Cr/Fe=0.29 and 0.19, respectively. These concentrations are almost equivalent to Fe²⁺Fe³⁺_1.33Cr³⁺_0.67O₄ and Fe²⁺Fe³⁺_1.5Cr³⁺_0.5O₄ spinels. Most of Cr³⁺ was recovered in the sludges, when solutions were treated in the range of 1500 to 4000 ppm of Cr³⁺. The products obtained from the solutions containing 1500 to 4000 ppm of Cr³⁺ were not identified by X-ray diffraction. On the other hand, most of Cr(VI), except for the part trapped in the spinel phase, remained in the filtrates, when the solutions contained 1000 to 4000 ppm of Cr(VI). All of the sludges containing heavy metals were strongly agglomerated with spherical particles of about O.1 μm in size.

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The effect of magnetic field on the dissolution of ir on plate in a hydrochloric acid solution has been studied by the measurement of the dissolution rate for 24 hours at 25°C with batch method. The magnetic field effect was dependent on the experimental conditions: When magnetic flux density of 0.15 T was applied, the dissolution was retarded in the solutions below 2.5 mol·dm^-3 hydrochloric acid, but accelerated in the solutions above 2.5 mol·dm^-3. Dependence of corrosion potentials and corrosion current densities on the hydrochloric acid concentration showed analogous behavior. The magnetic field effect was independent of crystal faces of the iron plate and of the magnetic flux density between 0.07 and O.15 T. The magnetic field affected the anodic reaction(Fe→Fe(II) +2 e) remarkably and promoted the oxidation of Fe(II) to Fe(III) in the hydrochloric acid solution.

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The adsorption of Cu(II) and Ag(I) ions on an active carbon fiber felt(KF-felt) was studied in connection with preparation of an air electrode. The activities of Cu- and Agdeposited electrodes were measured in reference to a zinc electrode, in comparison with the previous results for Ni, Pd, and Pt metals. The maximum power(P_max) of the zinc-air cell at 40°C in air increased with the amount of copper deposit up to 38 mg/g-felt, which was similar to the case of the nickel-deposited electrode. The P_max on Ag/KF-felt increased almost linearly up to the limited 209 mg/g-felt, which was superior to the values on Pd and Pt/KF-felt. Based on the discharge current measured at 1 V in the temperature of 40 to 60°C, the apparent activation energy(E_a) for oxygen activation process on 'Cu(38 mg) and Ag(209 mg)/KF-felt were estimated as 30 and 9 kJ/mol respectively. Such low E_a in Ag, 50% less than in platinum, suggested a quite high activity of silver metal on KF-felt. The current density for the Ag/KF-felt, measured at 50°C in oxygen stream under 1 V, in fact, was 100% higher than that for Pd and 37% higher than that for Pt/KF-felt. The current density for the Cu/KF-felt was 60% higher than that for Ni/KF-felt.

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Several bismaleimides were treated with 1, 1′-bis(methoxycarbonyl)divinylamine(BDA)under photoirradiation. Whereas the equimolar reaction gave a mixture of 1: 1- and 2: 1cycloadducts, the use of twice molar amount of BDA to bismaleimides afforded only 2: 1adducts, novel bis-type 7-azanorbornane derivatives, in fairly high yields. Spectral analyses of the products showed that the cycloaddition proceeded stereoselectively, giving the exoadducts.
Difference of the reactivity of bismaleimides from that of conjugated unsaturated compounds, reported previously, is discussed.

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