The K⁺ ions in K⁺-β″-ferrite were exchanged with Na^t, Rb⁺, Cs⁺, Ag⁺, T1⁺ and NH₄⁺ions in the corresponding molten nitrates at 200--450°C or with H30⁺ ions in concentrated H₂SO₄ at 90°C, respectively, to form M⁺-β″-ferrites. The lattice constant c_o, which depends on the thickness of alkali layers, increased with increasing ionic radius of the ion inserted in the layers. In addition, the K⁺ ions in K⁺-β″-ferrite were found to be replaced by Ba²⁺ ions in Ba(NO₃)₂ melt at 650°C to form Ba²⁺-β″-ferrite. However, when the K+-β″-ferrite was immersed in a molten salt of other divalent cations (Mg²⁺, Co²⁺, Ca²⁺, Zn²⁺, Cd²⁺, Pb²⁺ or Sr²⁺ ion), the structure of K⁺-β″-ferrite was rearranged to form a s pinel ferrite, α-Fe₂O₃, γ-Fe₂O₃ or SrFe₂O₄.
The Rb⁺- and Cs⁺-β″-ferrites were partially decomposed to form α-Fe₂0₃ at about 800°C, and then were transformed to β phase at above 1050-1150°C. Ag⁺- and T1⁺-β″-ferrites were rapidly decomposed to form α-Fe₂0₃ at above 600°C. NH₄⁺- and H₃0⁺-β″-ferrites were decomposed at the low temperature of 300°C to form γ-Fe₂O₃T as an intermediate phase, and this phase was transformed to α-Fe₂0₃ at 450°C. The formation of this intermediate phase may be due to the structural similarity of β″-ferrite to γ-Fe₂0₃.

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The stability region and synthesis of single crystals of black phosphorus under high temperature and pressure conditions were studied by using a piston-cylinder type high pressure apparatus. A graphite tube 6.2 mm in diameter and 20 mm long was filled with reagent grade red phosphorus, the starting material.
Red phosphorus was stable below a bout 700°C under 6 kbar, about 550°C under 10 kbar, and about 700°C under 4 kbar. The powdered black phosphorus, in pieces about 5 μm in length, was grown at 700 to 900°C under 6 kbar, and at 600 to 1000°C under 10 kbar (1.01 GPa). The temperature region of liquid phase was about 1000 to 1400°C under 6 kbar, and about 1050 to 1080°C under 10 kbar, Large single crystals of black phosphorus were consistently grown from this liquid phase.
The vapor phase regio n was found at above 1500°C under 6 kbar, above 800°C under 10kbar, and above 700°C under 3 kbar.
The maximum dimension of platy single, crystals of black phosphorus was 4.5 x 0.25 mm²and these plates usually have well-developed shapes and characteristic lustre.

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The kinetics of aniline liberation-anation reaction of [Co(Hbhpn)B₂]X₂ complexes {H2bhpn=N, N′-bis(2-hydroximino-1-methylpropylidene)-1, 3-propanediamine; B =aniline or its derivatives; X=Cl^-, Br^-, or I^- ion} have been studied in the solid state by the Coats-Redfern method on the basis of the thermogravimetry in nitrogen stream [Co(Hbhpn)B₂]X₂→[CoX₂(Hbhpn)] +2B↑.

The values of the rate constant and the activation energy (E_a) determined from the slopes of the straight lines in the plots of log [-log (1-α)/2.303.T²] vs 1/T, suggested that the above reaction follows the SN 1 mechanism. The values of the activation energy and the frequency factor were 150-188 kJ.mol^-1 and 10¹⁷-10²¹ s-^-1, respectively, for aniline liberationanation reactions. These E_a values were considered to reflect mostly the strength of the Co(III)-axial ligands (aniline derivatives) bonding. Furthermore, the enthalpy changes ΔH caused by the liberation-anation reaction of the [Co(Hbhpn)B₂]X₂ complexes were found to be about 2 times larger than those observed for analogous [Co(Hdmg)₂B₂]X complexes, where H₂dmg is dimethylglyoxime.

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In order to determine the amount of copper oxides on the surfaces of copper powders, an acid dissolution method was investigated. After the addition of copper powders to a 0.1mol·dm^-3-HCl H₂O-EtOH solution (50/50 by v/v, 200ml) containing octylamine (0.1g)followed by the dissolution of copper oxides on the surfaces into the solution for a period of 5 min, the dissolved copper ions were determined by an atomic adsorption technique and the amount of copper oxides was calculated. The most significant points for the acid dissolution method are to inhibit the reoxidation of surfaces of copper powders by complete removal of oxygen from the measuring flask, the addition of inhibitors to the solution and the use of organic solvents which are an inert solvent to tile oxidation of copper. The present method is applied to the determination of the amotint of copper oxides on the surface of copper powders of an average grain size of more than about 2.5 μm.

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Manganese contents and distribution in a clam shell were determined by graphite furnaceatomic absorption spectrometry and neutron activation analysis. The effect of several acids and major constituent elements in clam shell on atomic absorption spectrometry of 10 ppb manganese was studied. Hydrochloric acid, nitric acid, sulfuric acid and 10⁴-10⁶ fold amounts of calcium, magnesium and aluminum showed no significant interference. Therefore, in the present study, the direct determination of manganese in nitric acid-dissolved solutions of clam shell was carried out, using both the calibration curve and standard addition methods. The manganese content, 0.61-7.30μg/g, obtained by these experiments were in good agreement with the data obtained by solvent extraction-graphite furnace atomic absorption spectrometry and neutron activation analysis. Clear correlation between the manganese concentration in clam shells and the length from on umbo was shown.

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Autoxidation of azulene [1 A] at 110°C in HMPA (or DMF) yielded sixteen separable products, including three new compounds ([1 D₁], [1 E₁], and [1 G₂]). These products were monomeric, dimeric, and trimeric products containing an extranuclear carbon unit ([1 F], [1 G₁], [1 C], [1 G₂] and [1 D₁]), naphthoquinones ([1 E₄], [1 H₁], and [1 H₂]), benzenoids ([1 E₂], [1 I₁], [1 E₃], and [1 I₂]), biazulene [1 B], dimeric products with rearra ngement ([1 E₁] and [1 D₂]), and substituted azulene by the reaction with solvent [1 H₃]. The structures of these compounds were established on the basis of the spectroscopic data (UV, MS, IR, and NMR).

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On (ο-substituted phenyl)ferrocenes, the measurement of ¹³C-NMR spectra was carried out and assignments of the carbons of cyclopentadienyl rings were determined. The chemical shift of the α-carbon was found to be influenced by steric perturbation effect, and that of the β-carbon was influenced by inductive effect. On the other hand, both effects were recongnized as for the ipso-carbon. Further, unusual chemical shifts were found on the following carbons: (i) the a-carbon of (ο-nitro- and o-methoxycarbonylphenyl)ferrocenes, (ii) the α-, β- and 1′-carbons of (ο-hydroxyphenyl)ferr ocene. It was considered that these peculiarities were provoked by the charactaristic conformation of these three ferrocenes (Figs.2 and 4).

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The qualitative and quantitative analysis of polar compounds in coal-derived distillable liquids has been carried out by GC and Fl-MS to investigate the effect of the origin of coals on the product composition. The coals used were those of Battle River, Yallourn, Wandoan, Taiheiyo, Illinois No.6, Horonai and Miike.
The hydroliquefaction was carried out at 450°C for an hour under the initial hydrogen pressure of 100kg/cm² using a presulfided hematite as catalyst and tetralin as solvent, and also lignin hydrocracking was carried out on the same conditions. Three polar fractions (acidic, basic and neutral polar fractions) were separated from the distillate (bp 150-430°C) in each coal-derived liquid (Fig.1).
The yields of the acidic, basic and neutral polar fractions were 4.1-6.3%, 0.9-1.6% and 3.5-5.6% (maf basis) respectively. The main components of the acidic fraction were monocyclic alkylphenols and bicyclic phenolic compounds such as naphthols, indanols and tetralinols. The composition of this fraction was similar for the seven above coals, and was also similar to that of the acidic fraction obtained from the lignin-derived distillable liquid (Table 5).
The basic fra ction was composed of bi-, tri- and tetracyclic aromatic compounds containing basic nitrogen (Fig.2), while the neutral polar fraction was composed of nonbasic nitrogencontaining compounds and phenolic compounds with many alkyl groups attached to the aromatic ring (Fig.3-A, 3-B).
In bituminous coal-deriv ed liquids, the contents of polyaromatic compounds in phenolic and nitrogen compounds were high as shown in Table 6.

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In relation to the coal liquefaction, the reaction between hydrogen atoms and synthetic polymers has been studied.
Polystyrene, poly (thio-1, 4-phenylene), poly(methyl methacrylate) and poly[oxy(2, 6-dimethyl1, 4-phenylene)], of which thermal degradation behavior was already known, were subjected to the reaction with hydrogen atoms at temperature ranging from 25 to 300°C and under 133 Pa, using a hydrogen discharge flow apparatus (Fig.1).
Hydrogen atom irradiation caused degradation of polymers more effectively than heat treatment by a factor of 2 to 100 (Figs.2, 3). On heat treatment, polymers gave oligomers mainly composed of dimers, trimers and monomer (Tables 1, 2 and Figs.5, 6). On hydrogen atom irradiation, dagradation products comprised hydrogenated and/or hydrocracked monomers in addition to thermally degraded products (Figs.5, 6, 7). Structural feature of residual polymers was essentially similar to the original one.
These results suggested that hydrogen atoms enhanced the initiation steps of degradation reactions to give macroradicals by hydrogen abstraction from the polymers and/or selective addition to heteroatoms of the polymers.

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The distillable compounds produced by hydrocracking of thiolignin were analyzed using GC, GC/MS and 'Fl-MS.
Hydrocracking of thiolignin was performed at 450°C under initial hydrogen pressure of 150kg/cm2 using tetralin as a solvent and α-Fe₂O₃+S as a catalyst. Liquid products were separated by distillation into light (-280°C), middle (280-400°C) distilltes and residue (400°C+). Then the light and middle distillates were separated into acidic, neutral polar and nonpolar fractions (Table 1).
Quantitative an alysis of the acidic fraction in the light distillate by GC and GC/MS showed that monocyclic alkylphenols were main components and bicyclic phenolic compounds such as indanols, tetralinols and naphthols were contained (Fig.3, Table 2).
Three fractions in the middle distillate were characterized b y molecttler ion spectrum method using Fl-MS (Figs.5, 6, 7). The acidic fraction was composed of phenolic compounds with one and two hydroxyl groups, while the neutral polar fraction contains monphenolic compounds with alkyl groups. Results of GC/MS analysis of the dehydrogenated product of the nonpolar fraction showed the presence of polycondensed aromatic's such as phenanthlene, anthracene, pyrene (Fig.8).
From these product ana lysis, it was presumed that the polycondensed ring compounds may be formed during the hydrocracking of thiolignin.

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An octanucleotide of any sequence can be synthesized from two kinds of tetranucleotides. This paper reports the rapid and convenient method to prepare octanucleotides from two types of tetramers, X- and Y-types, which are designed to be _DMTr, N₁*pN₂*pN₃*pN₄*p_0- and _HON₁*PN₂*PN₃*PN₄*_bz, respectively, where DMTr, bz, and the symbol * represent the protectors of functional groups. The yields of the octamers prepared with very simple procedures in a small scale (sub-μp mole) were sufficient for DNA-sequencing and the octamers were proved to have enough activities as primers. The activities were directly examined by using them as primers for enzymatic DNA syntheses and analysing the products by gel electrophoreses. The method reported in this paper presents not solely easy accessability to varieties of oligonucleotides without expensive apparatuses but also general principles to prepare oligomers economically. Tetramers are suggested to be the fittest building blocks for high-rate production of varieties of DNAs.

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A complex was formed from bovine serum albumin (BSA) monomer, fractionated by liquid chromatography, with sodium dodecyl sulfate (SDS) by adding 2-mercaptoethanol.
The translational diffusion coefficient D of the complex was measured by dynamic light scattering in two phosphate buffer solutions of different concentration. The linear relationships between D and the solute concentration c were indicated for BSA monomer, SDS micelle and BSA-SDS complex. D=D₀(1+k_Dc)The diffusion coefficient at infinite dilution D₀ of BSA and SDS is larger in 20 mmol·dm^-3than in 100 mmol·dm^-3 solution. But a little smaller D₀ was found for the complex in 20 mmol·dm^-3 than in 100 mmol·dm^-3. The hydrodynamic radius of the complex was 5.76 nm, which is sufficiently large compared with 3.50 nm of BSA monomer and 2.49 nm of SDS micelle in 20 mmol·dm^-3 solution. The inter-particle interaction parameter k_D decreases with the electrolyte concentration. In 20 mmol·dm^-3 phosphate solution k_D value of the complex is markedly large compared with that of BSA or SDS. The variation of the inter-particle interactions, thermodynamic and hydrodynamic, by complexation is attributable essentially to the conformational change from BSA prolate ellipsoid to random coil chain of the complex backbone. In addition, the localization of electric charge of SDS micelles bound onto the backbone chain contributes to k_D, value of the complex in 20 mmol·dm^-3 buffer solution, beyond the effect by the molecular weight or hydrodynamic dimen sion.

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Symmetrical phospholipids having three polymerizable acyl groups, ο-[2, 2, 2-tris(2, 4 alkadienoyloxymethypethyl)ethyl]phosphocholines [2a-e] and their saturated models [1a-e] were synthesized (Scheme 1 and 2), and these were dispersed in water by sonication. Formation of (polymerized) vesicles were confirmed by DSC, electron microscopy, submicron partic le analyzer and GPC (Figs.1, 3 and 4, Tables 4 and 5). When the carbon number of the acyl chain was longer than 14, large unilamellar vesicles with diameter of 80-100 nm were formed (Table 5). Polymerized vesicles of [2a-e] were more stable than those of diacyl-type DODPC against detergent attack (Fig.5). They were stable even upon freeze-thaw treatment and against phospholipase D attack (Tables 6 and 7).

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It has been revealed by ESR studies that complexation of Cu²⁺ with deprotonated OH groups of PVA occurs in aqueous Cu²⁺-PVA solutions at pH13, forming a gummy precipitate. The inclusion-type complex of Cu(OH)₂-PVA produces [Cu(OH)₄]^2- by the addition of NaOH in the same degree of reactivity as Cu(OH)₂ alone, and the above complexation takes place between the resulting [Cu(OH)₄]^2- species and PVA, all the three Cu species being kept at equilibrium.

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Effect of the radiation-induced graft polymerization of monomers in vapor and liquid phases. to the hollow-fiber. membrane microfilter, made of porous high density polyethylene, upon the permeability of water has been studied. Determination of the flux of hollow-fiber membranes prepared by the graft polymerization of acrylonitrile, vinyl acetate, styrene, or acrylic acid revealed that the membranes prepared by vapor-phase grafting had a higher flux than those prepared by liquid-phase grafting. The measurement of pore volume and dimensional change revealed that hollow-fiber membrane grafted in vapor phase swells to larger extent. Cyano group of acrylonitrile and acetoxyl group of vinyl. acetate, , grafted to hollow-fiber membrane were converted to amide oxime and alcoholic hydroxyl group, respectively by the chemical modification. The flux of these functionalized membranes were determined and it is found that the functionalized membranes derived from vapor-phase gr afted membrane had higher water permeability than those derived from liquid-phase grafted ones.

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Activated carbon was prepared with alkali from such lignin products as lignin sulfonic acid, thiolignin, and black liquor. Dry distillation of 1/1 or 1/2 mixture of lignin sulfonic acid and NaOH gave carbonaceous residue at temperature above 300°C (Fig.1). Powdery activated carbon with good quality were, obtained directly by -careful washing of the residue without further activating process. The yield of activated Carbon was remarkably decreased from 0.19 to 0.04 with the increase in the relative amount of NaOH (lignin sulfonic acid/NaOH ratio from 1/1 to 1/3), although Na₂CO₃ showed a limited effect (Fig.2). The eff ects of the alkali ratio and the carbonization and activation temperature on the yield and the total surface area of the prepared activated carbon are eValuated from the surface developing diagrams in Figs.4 and 5. The diagrams indicate that the optimum alkali ratio and the temperature are 1 and 450°C, respectively.
Under similar conditions, pu rified lignins gave high quality activated. carbon (Table 1). Thus, the specific surface area of the activated carbon from thiolignin was 2751 m²/g by BET method. This value is very close to the upper limit of the surface, area of graphite. Furthermore, a 'activated carbon of reasonable quality was prepared from black liquor by removal of its inorganic constituents with calcium oxide.

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Photochromism in 10 b, 10 c-dihydropyrenes possessing the t-butyl groups at 2, 7-positions and various substituents at 10 b, 10 c, 4, 5, 9 and 10-positions in Fig.1 was studied. On each compound, an UV-visible spectrum of stable colored species, the rate constant of a thermal coloration reaction, the quantum yield of a photo-decoloration reaction, and a degradation behavior were investigated. The wavelengths of the absorption maxima of the colored states were summarized in Table 1, and the absorption spectra were compared in Figs.3 and 4. The rate constants and the activation energies of the thermal coloration were summarized in Table 2 and the Arrhenius plots were shown in Figs.5-7. The quantum yields of the photo-decoloration were summarized in Table 3. The results were examined in the viewpoint of three substituent effects interior 10 b, 10 c-positions of the dihydropyrene molecules, 4, 5, 9 and 10-positions of the conjugated rings, and the t-butyl groups at 2, 7-positions. The substituent effects were elucidated as follows: (1) the rate constants of the thermal coloration reactions were increased and the quantum yields of the photo-decoloration reactions were decreased when the bulky groups were substituted at 10 b, 10 c-positions, (2) the rate constants did not changed, but the quantum yields were increased, when an electron withdrawing group such as an acetyl group or a nitro group was introduced at 4-position, (3) the t-butyl groups at 2, 7-positions considerably decreased the quantum yields and caused the degradation reaction.

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Anthranilic acid is one of the most strong chelating agents. In order to lower the solubility of anthranilic acid in water, an alkyl group was introduced to its benzene ring i. e., 6-alkylated [4] and 5-alkylated anthranilic acid [8] were prepared by the Schmidt rearrangement of corresponding phthalic anhydrides and by the reduction of corresponding nitrobenzoic acids, respectively.5-Alkylated anthranilic acids [8] turned out to be good chelating agents for metal ions such as Cu²⁺, Co²⁺, pb²⁺, Cd²⁺, Ni²⁺ and Hg²⁺, whereas 6alkylated anthranilic acids [4] did not react with any metal ions, probably because of the strongly hydrophobic alkyl chain at the vicinity of the weak hydrophilic β-amino acid moiety as well as the steric hindrance for the chelation.
Cu²⁺ ion was extracted from aqueous solution of pH >2 to heptane solution of chelating agents [8] in 99% yield within 2 h shaking. The insoluble chelate thus formed was easily decomposed by shaking with 12% aqueous HNO₃ and released ca.95% of the metal ion back into acieous phase. Moreover, the chelating agents recovered were reusable,
The extraction of Hg²⁺ ion was carried by using a large excess of compound [8c]. After shaking for 22 h, almost, 98% of Hg²⁺- ion was bound to the agent. Unless it is highly acidic (pH <3), the Hg²⁺ ion release into aqueous phase from the organic phase was almost negligible.

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2-Chloro-4-(2-chloroethyl amino)-6-alkoxy-1, 3, 5-triazine reacted with p-toluidine at 120-130°C to give 4-(p-toluidino)-2, 6, 7, 8-tetrahydroimidazo[1, 2-a][1, 3, 5]triazin-2-one [5] in a good yield. But when the reaction was carried out at 80°C, the product was 2-(p-toluidino)4-(2-chloroethyl amino)-6-alkoxy-1, 3, 5-triazine [4]. Reaction of [4] with p-toluidine at 120-130°C did not give [5].

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The palladium-catalyzed alkynylation of 4, 6-disubstituted 2-iodo-1, 3, 5-triazines [1] (substituent a, NMe₂; b, Ph; c, OMe) with monosubstituted acetylenes [2] (substituent a, Ph; b, COOMe; c, CMe₂OH) afforded the corresponding cross-coupling products [3] in moderate yields except for the case of [2 c]. The cross-product [3 ac] reacted with [1 a] to give bis [4, 6-bis(dimethylamino)-1, 3, 5-triazin-2-yl]acetylene.

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