The electron spins in organic molecules and molecular assemblies have a tendency to pair off. Special molecular designs are necessary to achieve intra- and intermolecular spin alignments. Theories dictating a number of degenerate orbitals and the corresponding number of electrons in alternant hydrocarbons are briefly surveyed. Based on these theories, high-spin polycarbenes PhC(m-C₆H₄C)_n-1, Ph and 1, 3, 5-[PhC(m-C;₆H₄C)_n/3-1]₃C₆H₃ have been designed. The corresponding polydiazo compounds were synthesized, doped in single crystals of benzophenone, and photolyzed at cryogenic temperatures. The ground nonet state of the, linear tetracarbene, for example, was confirmed by its ESR fine structures and paramagnetic susceptibilities. The magnetic moment of the tetracarbene is the highest ever reported for molecular or ionic entities. Isomeric bis(diazo)[2.2]paracyclophanes were synthesized and photolyzed similarly to find, in good agreement with the McConnell's theory on the ferromagnetic intermolecular interaction between organic free radicals (1963), that the pseudoortho and pseudopara dicarbenes have the ground quintet state while the pseudometa isomer is in the ground singlet state. A strategy for increasing the spin ordering over the high-spin aromatic molecules by orienting the stacking mode was thus obtained. Relevance of these results to macroscopic ferromagnets is exemplified. Newer molecular design of high-spin polymers consisting of the polyacetylene, polydiacetylene or polyphenylene main chai n and carrying the radical centers in the side chains is quite promising from the point of view to construct new organic magnetic materials of practical use.

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Four linear equations have been found from the data of 64 ions at 298 K between the standard enthalpy and entropy of. hydration, ΔH°_h and ΔS°_h These eqesuea tions can be expressed in terms of r²_e (A²) using the following effective ionic radius re as introduced in the previous paper (J. Phys. Soc. Jpn., 55, 1021(1986)): where ΔH°_{h, o} is the constant, characteristic of a group of ions, and z is an effec tive ionic charge. According to the equations, 64 ions are classified into Group I (14 ions. ΔH°_{h, o}=-163 kJ.mol^-1and z f=1), Group I' (9 ions. ΔH°_{h, o}=-168kJ.mol^-1 and z f=1/3 or 2/3), Group II (15 ions. ΔH°_{h, o}= -265 kJ.mol^-1 and z f=2), and Group III (26 ions. ΔH°_{h, o}=0 and z f=3), in which H+ is fit for Group III, and. SO₄^2- takes z f=3/2 in Group II. Using Eq. (a) and ΔS°_h=-26.1r²_e (J.mol-1.K-1) from the previous result, the standard Gibbs energy of hydration at 298 K can be expressed as to examine the individual ionic values estimated in comparison with the thermodyn amic values. The second term on the right side of Eq. (b) describes the comp ensation effect on the ionic hydration through the mediation of r2e Moreover, the second term on the right side of Eq. (a) can be ascribed to an ion-water dipole interaction energy, by which a restriction is imposed between r_e and the distance R from the central ion to the water dipole. √εRr_e =2.74A2 with ε representing the relative permittivity of th e hydration sphere. For 51 monoatomic ions, the following linear relationship was obtained, between the value of. √εR or 2.74/r_e(A) and the Pauling ionic radius r_i where A and B are the constants depending mainly on the, absolute magnitude of, ionic charge z.

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The kinetics of electtochemical oxygen reduction of five transition metal nitrides in NaOH solution were examined by use. of a rotating ring-disk electrode (Table 1). It was found that Mn₄N has the highest catalytic activity for the direct four-electron oxygen redu ction among the nitrides studied, and that CO₃Na lone is active in decomposing HO₂- to OH- The best performance of poly(tetrafluoroethylene) (PTFE)-bonded carbon e lectrodes (Fig.1)was also observed with Mn₄N loading, (Fig.2). When the amount of Mn₄N, was varied at a fixed PTFE content (15wt%), two maxima appeared at 20wt% and 60wt% in electrode performance (Fig.3). The highest cat h ode performance achieved at 60wt% Mn₄N, showed a current density as high as 2400mA/cm² at -125mV vs. Hg/HgO (0.8 V vs. RHE) in 9mol/dm³ NaOH at 80°C, which was 24 times larger than that for a carbon electrode without ca talysts (Fig.4 ). The same electrode was well stable in a Short term operation for 50h at a current density of 300mA/cm², except a slight lowering in electrode potential observed during initial 25h (Fig.6). XRD an a lysis reveals that the crystal structure of the Mn4N catalyst is stable for the 50 h operation (Fig.8), while XPS analysis suggests that the surface of the catalyst is covered with a thin oxide layer (Fig.9).

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The electrical conductivity of defect perovskite-type oxides, SrZr_1-xAl_x0_3-α (0.02≤x≤0.15), has been investigated to clarify the effect of aluminium doping both on the oxide ion conduction and on the hole conduction in the grain as well as in the grain boundary of the oxides. The complex impedance of these oxides was measured as a function of temperature and oxygen partial pressure. The possible equivalent circuit for a mixed condu ctor was considered to be expressed by a series of the grain impedance and the grain boundary impedance, Jpoth of which are composed of a parallel combination of resistance and capacitance based on the oxide cie ion conduction and resistance based on the hole conduction (Fig.1). The resistance and capacitance of the grain and the grain boundary based on the oxide ion conduction were independent of P_o2. On the other hand, both the resistance of the grain and the grain boundary based on the hole conduction varied significantly with P_o2, showing the hole conductivity in both of them to be proportional to P_o21/4 (Fig.7). It is revealed that the discussion of an electrical conductivity of a mixed conductor can be carried out in more detail, than ever by employing the complex impedance analysis based on the equivalent circuit proposed in this study. The solubility limit of Al₂0₃in SrZr0₃ was deduced to be close to 2mol % from the variation in the unit cell volume, the activation energy for migration of oxide ion vacancy, and the oxide ion transference number, the last two properties being resolved for the grain and the grain boundary, respectively, by the analysis of the complex impedance plots for the oxides (Figs.9, 11). Furthermore, both oxide ion conductivity and oxide ion transference number of the SrZr_1-xAl_x0_3-α system were concluded to be controlled by the behavior of oxide ion in the grain boundary.

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We have studied and developed the molded metal oxides catalyst bound by calcium aluminate which, is composed of EMD(stand for electrolytic manganese dioxide), calcium aluminate (alumina cement, referred to as AC) and Si0₂. This catalyst has good performance because it, has high, specific, surface area. It is commercially available as a home-use catalyst. The production method of the catalyst is as follows; catalyst components in powder form were well mixed and then adequate water was added to the mixed powder to make the mixture paste for molding pellet or honeycomb. The curing of the molding was done in hot water and then catalyst was calcined at low temperature. The purpose of the paper is to 'study the molded meta l oxides catalyst, especially EMD and FEMD (F stands for fibrous), bound by calcium aluminate. We prepared two types of catalysts; a particle type made of EMD and FEMD, and a mold type composed of EMD-AC-Si0₂. The relationships among CO conversion efficiency, these two types catalysts, effect of SO₂ gas in exhaust gas, effect of x value of MnO, _x and its specific surface area have been investigated. The main results obtained were as follows, 1) The particle catalysts showed high CO conversion efficiency at 200 to 400°C, but it was effected by SO₂ in exhaust gas.2) The mold catalyst showed also high CO conversion, and it was not so much effected by. SO₂ gas.3) Sin tering of particle catalyst began gradually above 300°C and specific surface area of these particle began to reduce, but x value of MnO_x did not change, but the particle catalyst was much more subjected to SO₂ damage than the mold catalyst and specific surface area and the x value of particle catalyst began to reduce by SO₂ gas.4) The mold catalyst was more stable and active than the particle catalysts and also the surface area and the x value not be so much influenced in SO₂ gas.

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We have studied and developed the molded metal oxides catalyst bound by calcium aluminate which is composed of EMD (stand for electrolytic manganese dioxide), AC (stand for alumipa, cement, calcium aluminate), Si0₂ and promoters such as Cub and Fe₂0₃. It has been commercially available as a home-use catalyst. The purpose of the paper is to stud y the molded metal oxides catalyst, especially EMD, and promoters like CuOx and FeOx, bound by calcium aluminate. The relationships among CO conversion efficiency, the molded catalysts composed of EMD-AC-Si0₂-promoter such as CuOx and FeOx, optimum amounts as promoter in molded catalyst, and most suitable calcined temperature of molded catalyst have been investigated. The main results obtained were as follows. 1) The mold ed catalysts composed of EMD-AC and EMD-AC-Si0₂ showect h igh CO conversion efficiency at 200 to 400°C. 2) Verdigris and copper nitrate are suitable for promoter out of copper compounds, but we selected finally the verdigris as optimum promoter, which meet with high CO conversion, mechanical strength of catalyst and reasonable cost. 3) We also studied the iron compounds as promoter such as FeO(OH), Fe(COOH)₂, Fe(OH)₃, Fe₂0₃ and Fe₃0₄, and FeO(OH) is adopted as promoter out of them. 4) The best component for the molded catalyst was EMD: 60, AC: 25, Si0₂: 5, CuCO₃Cu(OH)2. H₂0: 5 and Fe0(OH): 5.

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We have studied and developed the molded catalyst bound by calcium aluminate which is composed of AC (stands for alumina cement), fused silicon dioxide, titanium dioxide as the carrier and a small amount of Pt and Pd. This catalyst has good performance because it has no washcoat layer and also it has a high specific surface area. It has been commercially available as a home-use catalyst. The production method of the cataly st is as follows. carrier components in powder form are well mixed and then adequate water is added to the mixed powder to make the mixture paste for molding honeycomb. The curing of the molding carrier is done in hot water and then Pt and Pd are supported on the carrier and the catalyst is calcined at low temperature. The purpose of the paper is to study the molded catalyst bound by AC. The relationships among CO conversion efficiency, several kinds of AC, effect of TiO₂ contents in the carrier, effect of catalyst combination (Pt/Pd), effect of thermal decomposition of noble metals salts, optimum amounts of noble metals, catalyst performance in kerosine space heater have been investigated. The main results obtained were as follows. 1) This molded catalyst using AC of 1st grade shows the best CO conversion and deflection strength than other AC's. 2) Optimum Ti0₂ contents in this carrier are 20 to 50 wt% of carrier components (Al₂0₃.CaO, Ti0₂, Si0₂), and TiO₂ improves CO conversion at 150 to 700°C, but does not improve conversion above the temperature of 800°C.3) Pt/Pd: 2/1 catalyst combination is effective a nd shows better CO conversion and longer life than Pt only catalyst.4) Optimum th ermal decomposition temperature of noble metal salts is 500 to 600°C for this catalyst.5) This catalyst shows good performance in kerosine heaters.

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Hydrolyses of coexisting NH(SO₃NH₄)₂ and NH₄SO₃NH₂ has been studied in the presence of guanidinium sulfate and (NH₄)₂SO₄ from 100 to 160°C, at which temperature range no decomposition of guanidinium ion was observed. It was confirmed that hydrolysis of the NH₂S0₃^- in an aqueous solution was much slower than that of NH(S0₃^-)^2- in the same solution and that the former hydrolysis proceeds through the reaction between NH₂S0₃^- and H₃0⁺ formed by the preceding hydrolysis of NH(S0₃^-)₂. On the other hand, hydrolysis of the NH₂S0₃^- in the presence of a small amount of water was found to be accelerated by the addition of NH(S0₃NH₄)₂ and to occur in preference to that of the coexisting NH(S0₃)₂ above 120°C. The reaction path in this case was presumed as follows. An actual reaction mixture(guanidinium ion: 14.4, NH₄⁺: 14.5, SO₄^2-: 30.6, NH(S0₃^-)₂: 23.5, NH₂S0₃^-: 13.9%) obtained in a guanidine synthesis was hydrolyzed in the presence of a small amount of water on the basis of the above results. It was readily converted into a mixture of guanidinium sulfate, (NH₄)₂SO₄ and H₂SO₄.

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Recently many authors have much interested in making ceramics from a variety of organometallic compounds by pyrolysis. We report some experimenta l conditions for making suitable precursors easy to form ceramics by use of silazanes as starting materials and describe the following factors: i )kinds of methylchlorosilanes, ii) their combinations and molar ratios, iii) molecular weight increase and gelation-time of the polysilazane precursor, and iv) thermal properties of the precursors analysed by thermogravimetry. Methyltrichlorosilane or dimethyldichlorosilane was allowed to react with gaseous ammonia in benzene at room temperature or in diethyl ether-liquid ammonia mixture at -50--40°C. Binary mixtures of methyltrichlorosilane/dimethyldichlorosilane or methyltrichlorosil ane/silicon tetrachloride with different molar ratios also underwent co-ammonolysis in diethyl ether-liquid ammonia mixture. The liquid products having low molecular weight initially obtained were either viscous and opaque or viscous and transparent. Their molecular weight was found to be increased by being kept at a constant temperature and they finally transformed into gel. Thus, the most suitable precursors for ceramics via polysilazane were obtained_ by the combination of methyltrichloroisilaneklimethyldichlorosilane with an appropriate molar ratios.

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Bis(acetato)bis(imidazole)copper(II) ([Cu(CH₃C00)₂(HIm)₂], [1], bis(acetato)tetrakis(imidazole)copper(II) ([Cu (CH₃C00)₂(HIm)₄], [2]), and poly[bis (imidazolato)copper(II)][Cu(Im)₂]_n, three isomers [3]=[4], [5], and [6]) were synthesized, and the thermal properties and the configuration of these complexes were investigated by thermal analysis and measurements of magnetic moments and electronic spectra. The magnetic moments of [1]and [2], which were highly soluble in water, methanol and ethanol, were 1.83-1.88 BM. The complexes [3]-[6], which were sparingly soluble in ordinary solvents, had the subnormal magnetic moment of 1.47-1.65 BM, and the magnetic interaction was observed to exist between Cu(II)-Cu(II). It was presumed that [1]and[2]in the solid state were the complexes of the square planar type and the distorted octahedral type, respectively. The complexes [3]and[4]blue in color, being the same isomers, were the polynuclear complexes of the square planar type, and [6] green in color was a polynuclear complex of the octahedral type. The configuration of the polynuclear complex[5]purple in color could not be estimated. The complex[6]of the three isomers of [Cu(Im)₂]_n revealed the high thermal stability.

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The ultraviolet absorption spectra of N-(2-hydroxybenzylidene)-2-hydroxy-5-(substituted)anilines[1](CH₃[1a], H[1b], SO₃H [1c], Cl[1d], and NO₂[1e]) were investigated in methanol, methyl cellosolve, and N, N-dimethylformamide, the mixed solvents of these with water. It was found that[1]exsisted as a species with an intramolecular hydrogen bond of I in the neat solvents, and as a molecular species of H₂L which has no intramolecular hydrogen bond in the mixed solvents with water. The absorption bands of the molecular species were assigned to the first and the second bands (A-1 and A-2)for the benzene ring of benzylidene side (hereafter denoted A) and those (B-1 and B-2)for the benzene ring of aniline side (hereafter denoted B) (Tables 1 and 2). In the mixed solvents with water (7/3 v/v) of pH 8.1-13.0, the absorption bands observed at 258-269 nm (A-1) and 378-381 nm (A-2) are due to I-HL-([1a]-[1b]) and II-HL-([1e]) a nd those observed at 294-442 nm (B-2) are due to L^2-, respectively. By use of these absorption bands corresponding to molecular and ionic species, the acid dissociation constants (pKa) were determined in the mixed solvents with water (7/3 v/v) at 25±0.1°C. It was found that the pK_a1 (9.1-10.1) and pK_a2 (10.1-12.9) of[1a]-[1d]were acid dissociation constants corresponding to the hydroxyl group on A and B, and pK_a1 (8.O-8.6) and pK_a2 (8.4-9.2) of[1e] were those corresponding to the hydroxyl group on B and A, respectively. Due to the inductive effect of the substituents on B, the pK_a1 values of the hydroxyl group on B decreased in the order of[1a]>[1b]>[1c]>[1d]>[1e]. On the contrary, field effect plays an important factor decreasing the pK_a values of the hydroxyl group on A.

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Chlorophyll and chlorophyll degradation products are very important compounds as indicators of bioactivity in water and/or sediments. Chlorophyll and chlorophyll degradation products were extracted from core samples collected from the Inland Sea of Japan and separated by high-performance liquid chromatography using Zorbax ODS column (250 mm x 4.6 mm I. D.) as the stationary phase and acetonitrile-acetone (45:55 v/v) as the mobile phase at a flow rate of 0.6 cm3.min-1 The effluent from the column was monitored with a spectrofluorometer by using an excitation wavelength of 410 nm and an emission wavelength of 670 nm. Chlorophyll a, pheophytin a, pheophorbide a, methylpheophorbide a, pyropheophytin a and pyropheophorbide a were identified as the predominant components in sediments. From vertical distribution of chlorophylls, it is presumed that 45 years elapsed for the accumulation of methylpheophorbide a and 85 years was required for the release of methoxycarbonyl groups such as pyropheophytin a and pyropheophorbide a.

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Reactions of anthraquinone and anthrone with primary amines or thiols in the presence of titanium tetrachloride were studied. Anthraquinone reacted with primary amines to give N, N'-disubstituted anthraquinone diimines, while the reaction with thiols afforded 9, 10-bis(alkylthio or phenylthio)anthracene. Anthrone gave 9-(alkylamino)anthracene and 9-(alkylthio or phenylthio)anthracene by the reactions with amines and thiols, respectively. It was suggested that these 9-substituted anthracenes may be produced by dehydration of 9-substituted tetrahydro-9-antrol intermediates.

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The reaction of d_o-, 1, 1-d₂-, 2, 2-d₂- and 4, 4, 4-d₃-1-butanethiols with H and D atom have been investigated at room temperature, under 530 and 2660 Pa, using a conventional discharge flow apparatus. Butane and 1-butene were produced mainly. Small amounts of ethylene, propylene, propane, and ethane were also detected (Table 1). Relative amount of butane increased slightly as conversion increased, while that of 1-butene decreased (Figs.1 and 2). The decrease of 1-butene could be accounted for by secondary reactions with H/D atom (Table 2). The numer of D atoms in unreacted thiols was unaffected by the reaction. The number of D atoms in butane remained unchanged with that in the substrate thiols when the reaction was carried out with H atom, but it increased precisely by one when reacted with D atom (Table 3). The number of D atoms in 1-butene remained unchanged in the reaction of d_o-, 1, 1-d₂and 4, 4, 4-d₃-1-butanethiols, irrespective of the reaction partner, H or D atom. But one D atom was lost in 1-butene from 2, 2-d₂-1-butanethiol (Table 4). Deuterium distribution in butane and 1-butene can be explained by abstraction and addition reaction between butyl radical and H/D atom. However, the amount of 1-buten e can not be explained only by these reactions, since the abstraction/addition ratio is estimated to be small, ca.0.05 (Table 5). The D atom distribution and relative amount of 1-butene were taken in support for concomitant elimination of mercapto group and hydrogen at the second position from the substrate thiols. From these results, the fo llowing scheme is proposed.

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Polycarbosilane(PCS) is organic polymer which consists of the skeleton of Si-C bond. SiC fiber is produced from PCS by the steps of spinning, curing and heat treatment. Curing process of SiC fiber is generally oxidation reaction of PCS by heat treatment in air. Structures and characteristics of SiC fiber is affected by oxidizing conditions of PCS. However, details and mechanism of PCS-oxidation has not yet been clarified. Therefore, the change of PCS after oxidation in air was studied by measurement of weighing, oxygen analysis, mp, GPC, solubility in THF and infrared spectrum. The oxidation of PCS gave the following reaction.1) oxidation reaction of two SiH bonds followed by condensation to give Si-O-Si bond, 2) hydration of SiH bond to give SiOH bond, 3) oxidation reaction of SiCH3 bond to give SiOH bond and formaldehyde, 4) dehydrated condensation of two SiOH bonds to give Si-O-Si bond, (reaction eq. (1)-(4)). PCS became infusible by crass linkage of Si-O-Si bonds. However infusible PCS consisted of more than 7 wt% of oxygen because it had more SiOH bonds than Si-O-Si bonds (Table 2). Condensation reaction of SiOH bonds has also given Si-O-Si bond by heat treatment in nitrogen. By applying this fact, we obtained the infusible PCS which consisted of 3-6 wt% of oxygen (Table 3).

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Coal oil produced by hydrogenation of Japanese Akabira coal was distilled to 25 narrow boiling point fractions. Subsequently, 9 fractions of them were separated by amine column HPLC into the compound classes, paraffin, aromatic ring classes and polar comPounds. Aromatic ring classes which are monocyclic aromatic (Fr-M), naphthalene type (D1)and biphenyl type (D2) bicyclicaromatic compounds for coal hydrogenation oil have specific ¹H-NMR spectra, reyealing aromatic hydrogen and of α-alkyl hydrogen substituted onto aromatic rings. Thus, signals of various bonding type hydrogens can be nicely separated without overlapping each signal among homologous aromatic ring classes. The assignments of each peak for aromatic ring classes were made by comparing them with reference ¹H-NMR spectra. for compounds corresponding to monocyclicaromatic, naphthalene type and biphenyl type bicyclic and polycyclicaromatic ring class. All spectra from respective aromatic ring class for coal liquid show the same spectral patternes and their chemical shift ranges have agreed fairly well with the ranges of resonance peaks of hydrogen in various bonding types cited in the reference spectra. Structural analysis of coal liquids proposed o riginally by Haw et al. for finding various bonding types of carbon in aromatic ring classes was attempted for establishment as a routine analysis, designated to the HPLC-¹H NMR method. The distribution of various bonding type of carbons for monocyclic and naphthalene type bicyclicaromatic class according to this analytical method correlated with the boiling point of their fractions. The correlation was found among also low molecular weight reference compounds. This means that HPLC-¹H NMR method gives detailed and accurate results for structural analysis for coal liquids.

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The synthesis of N-octadecylsquarylium (SQ) dyes[3]and[4]was studied. A mixture of N-octadecylated intermediate[1]or[2](2 mol) and squaric acid (1 mol) was refluxed for 24 h in 1-pentanol-chlorobenzene (3: 2 vol.) (Method A), or heated at 160°C for 5 h in the presence of Nafion-H resin (Method B). Method B was superior to method A with respect to the yields of[3]and[4](Table 2). The yields of[3]were affected by the electron egativity of X and were in the order of X: CMe₂>Se>S>O. In the case of[4], good yields were attained for R⁴ which was an electron-releasing substituent such as OH or Me. IR and NMR measurements revealed that[3]and[4]have symmetrical 1, 3-bonded squarylium rings, which are consistent with the result of N-methyl SQ dyes reported by Treibs et al..

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Cis-diamminedichloroplatinum(ll) complex (cis-DDP) is widely utilized as an anticancer agent for clinical treatments of various cancers. It has been confirmed by many evidences that cis-DDP binds specifically with DNA in cancer cells to inhibit the replication of the DNA. Therefore, many investigations concerning novel platinum complexes with various carrier ligands have been developed to be used as anticancer agents. However, the study on the platinum complex coordinated with a ligand containing sulfur atoms has not been reported yet. In this paper, a novel platinum complex, dichloro(2-aminoethylsulfony1)platinum(II), was synthesized. The structure of the platinum complex was analyzed by IR and ¹³C-NMR spectra, elementary analysis and atomic absorption spectrophotometry. The investigations were also carried out on the interaction between the platinum complex and DNA constituent nucleosides by analyzing the UV difference spectra and the liberation rate of the chloride ions from the platinum complex. The isosbestic points were observed in the UV difference spectra for the platinum complex-nucleoside system. It was also found that two chloride ions were liberated from the platinum complex in the interaction with the nucleosides. The platinum complex was found to exhibit a specific cytostaticcytotoxic activity against adriamycin resistant cancer cells.

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The formation of organic thin films on metal surfaces by using 6-substituted 1, 3, 5-triazine-2, 4-dithiol monosodium salts (RTDN) has been investigated under various conditions. The thin films formed on metal surfaces when metal plates were immersed into RTDN aqueous solutions at 20-90°C for 5-60 min. The rate equation of formation o f the organic thin films was given by a paraboric law when the carbon number of 6-substituent s in RTDN were below ten, or by a linear law, when the carbon number over ten. The rate increased with an immersion temperature and the concentration of RTDN, and was influenced by the kinds of RTDN and metals. By selecting various functional grou ps as 6-substituents in RTDN, it will be possible to endow various functions onto metal surfaces. The formation of organic thin film was possible on various metals such as copper, nickel, zinc, lead, brass, cupronickel, and stainless steel. The FT-IR and ESCA spectra and surface tension of the films showed the main component of the thin films changed depending upon the chain length of the 6-substituent. Whereas the groups of carbon number less than ten gave 6-substituted 1, 3, 5-triazine-2, 4-dithiol monothiolates, the longer chain groups produced 6-substituted 1, 3, 5-triazine-2, 4-dithiols. These results led to the conclusion that the formation of organic thin films on metal surfaces by using RTDN occurs by the diffusion and the build-up mechanisms which varies with the carbon number.

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Crystallization and stability of title vanadium(V) oxide (V₂0₅) have been studied as a function of temperature and time. Heat treatment temperatures were 150, 160, 170, and 180°C. Crystallinity was obtained by X-ray analysis and the results are displayed as timetemperaturetransformation (T-T-T) diagrams. The times required for initiation and completion of crystallization were as follows. Existence of an unidentified crystalline phase in an early stage ol crystallization was detected by X-ray analysis.

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The frozen pastes of uncalcined and calcined sodium-montmorillonites having various water contents were prepared in order to determine the interlayer spacing (d(001)) using an xpray small angle scattering. The samples calcined at the temperatures below 600°C-still swelled due to water vapor, while those calcined above 700°C did not. From the differential scanning calorimetry (DSC) measurements of these samples, the heat of fusion was determined. It was found that the unfrozen water existed even in the frozen paste of sodiummontmorillonite calcined below 600°C and that the amount was O.45 g-Water/g-Clay. Because the unfrozen water did not exist in the frozen paste of sodium-montmorillonite calcined above 700°C, it is suggested that the unfrozen water exists only in the interlayer space but not in the interparticle space. On the basis of the amount of the unfrozen water and the volume of the interlayer space, the density of the unfrozen water was estimated to be 2.0 g/cm³.

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Decomposition of ethylene glycol by the combined use of an ozone oxidation method and an electrolytic one was studied by changing the concentration of ozone in th e feed gas, the current density, the quantity of NaCl and the concentration of ethylene glycol. The order of the reaction with respect to ethylene glycol was O.8 and the rate constant increased with an increase of the concentration of ozone in the feed gas. Glycolald ehyde, glyoxal, glyoxylic acid and formaldehyde were detected as decomposition products, and the removal of total organic carbon (TOC), which was not attained by eithers of the two methods, was attained. This effect is considered to be caused by active radicals whi ch are formed during the course of this reaction. The decomposition route is estimate d as follows. From this scheme and the fact that a considerable amount of formaldehyde produced, is likely that the TOC removal via formic acid is important as well as that via oxalic acid. The TOC removal was remarkably affected by the concentration of ethylene glycol in addition to the conditions of ozone oxidation and electrolysis method.

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The adsorption behaviour of, boron in aqueous solution on commercially available chelating resins with N-methyl(polyhydroxyhexyl)amino groups was investigated by means of batch and column tests. This study was undertaken for the development of a process employing a chelating resin to recovery boron from brines accompanied by natural gas. The resinsused as boron adsorbents were Amberlite IRA-743, Diaion CRB 02, Duolite ES 371 and Uniselec UR-3500. All resins exhibited a satisfactory adsorption ability for boron in aqueous solution. the optimum pH range between 8 and 10 was obtained from the batch tests. The column tests were performed by loading the model sample corresponding to natural gas brines to the resin bed 10 cm³ (10 mmφ x 130-140 mm). When the model sample of (100 mg/dm³ boron) was passed through the column at the space velocity(SV) of 15 h-1, the break-through points at 30, 25, 35 and 20 dm³/dm³-Resin were obtained for IRA-743, CRB 02, ES 371 and UR-3500, respectively. The elution of boron adsorbed on the resins was accomplished by passing one bed volume of 1 mol/dm³ sulfuric acid solutions and subsequently 5 bed volumes of water at the SV of 7.5 h-1. The cyclic operation of column was found to be satisfactory when all resins were regenerated with 1 mol/dm³ sodium hydroxide solution. The results indicate that the four resins tested can be applied to. the process for recovery of boron as boric acid from natural gas brines.

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2-Phenanthrol (0.1 mol) was added to a slurry of dichlorotriphenylphosphorane in CCl4obtained from O.11 mol of triphenylphosphine and 0.11 mol of chlorine. After the mixture was stirred for 30 min at 70 °C, the solvent was removed, and the residue was further heated at 320-340°C until evolution of hydrogen chloride ceased. Extraction of the mass by hexane gave crude 2-chlorophenanthrene in a yield of 59%, mp 85-85.5 °C after recrystallization from ethanol. Bromination was carried out similarly. All five isomeric phenanthrols and some monochloro- and monobromophenanthrols were converted to the corresponding halophenanthrenes and the dipole moments of the latter were measured. The results are given in Table 1.1-Chloro- and 1, 3(?)-dichloro-2-phenanthrols also were newly prepared by chlorination of 2-phenanthrol as shown in Scheme (2).

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9-Phenanthrol had been known to give the 10-substituted compounds on the electro-philic substitutions. In this paper the second site of bromination of[1]was established as follows. Dibromo-9-phenanthrol, obtained by bromination of[1]in CS2, was converted to bromo-9-phenanthrol[4]by reduction with Zn/AcOH.[4]was converted to dibromophenanthrene[6]by Bucherer's reaction followed by a modified Sandmeyer's reaction as shown in Scheme (1). Compound[6]was identified as 3, .6-dibromophenanthrene by comparison with an authentic specimen obtained from 9-bromo-3-phenanthrol. Accor-dingly, the second bromination of[1]is revealed to occur at the 3-position.

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Branched polymers were synthesized through the process of molecular-weight-decrease reaction in the presence of silica-alumina catalyst. Gaseous products, liquid products, branched oligomers (Mw=400) and branched polymers (M_η=1.1x10₄-2.8x10₄) were obtained by the reaction. The straight-c1iain branches (C₁-0₅, C₆ and/or higher) and branched branches (2-ethylhexyl, 2-ethylpemtyl and 2-ethylbutyl) were found in the branched polymer by means of ¹³C-NMR measurements. The highest concentration of total branches in the polymer was 71 branches/1000 CH₂ and the yield of the polymer was 20 wt%. This concentration is much higher than that in commercial polyethylenes containing 10-20branches/1000 CH₂. Similar branches were, also found in the branched oligomer.

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