Photoionization of becteriochlorophyll a (Bchl), the most essential pigment in bacterial photosynthesis, in organic solution and the photoconductivity of Bchl in solid state were studied for the purpose of understanding the photoelectronic processes of the pigment in vitro.
Bchl was extracted from photosynthetic bacteria, Chromatium vinosum, and was purified by chlomatography on a sucrose column. The ionic species such as Bchl^± in solution were detected by the electrical conductivity measurements.
The excitation spectrum of photoconduc tion in Bchl solution agreed well with the absorption spectrum (Fig.1). When the solution was irradiated by a visible and near infrared flash, the photocurrent rose slowly as compared with the rise of T-T absorption (Fig.2). The molar extinction coefficient 2.0× 10⁴ mol^-1⋅dm³cm⋅^-1 at 510 nm, was used to determine the concentration of triplet molecule (3Bchl). The concentration of Bchl^± was calculated from the photocurrent, by assuming the ion mobility being 5×10^-4 cm²⋅V^-1⋅s^-1. As shown in Fig.3, both the decay of 3Bchl and the rise of Bchl^± were first order reactions. The rate constant of Bchl^± rise (4.3×10⁴s^-1) was almost twice as large as that of ³Bchl decay (1.8×10⁴s^-1). Ionization proceeded from electron transfer between triplet molecules of Bchl. The second order rate constant of the electron transfer reaction was estimated to be 1×10⁸ mol^-1dm³⋅s^-1.
A rapid response of the photocurrent due to the direct ionization was obs erved on the excitation of a UV nitrogen laser (Fig.5).
Photoconduction was observed in sol id state Bchl which was composed of Bchl-water adducts. The excitation spectra of the photocurrent and an absorption spectrum are shown in Fig.6. A typical response of the transient photocurrent is shown in Fig.7. The initial value of the photocurrent was proportional to O.8 power of light intensity. The carrier generation was ascribed to the dissociation of a singlet exciton.

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Effects of potassium dihydrogenpyrophosphate, boric acid, and sodium acetate as bath components on the ruthenium electrodeposition from aqueous sulfuric acid solutions have been studied of their roles during the electrodeposition and the improvement of the deposition surface. The potential for ruthenium deposition from the ruthenium(IV) sulfate solution was found more noble than that for hydrogen evolution in sulfuric acid solutions, with depression of hydrogen evolution. Addition of potassium dihydrogenpyrophosphate and sodium acetate made the potential more noble. The former of the bath components increased the limiting current density for H+ reduction and controlled the pH variation of the electrode surface. The ruthenium electrodeposition is considered to have a crack and a great stress in electrodeposit. However, the potassium dihydrogenpyrophosphate had a remarkable effect on the improvement of smoothing the surface. Boric acid was absorbed on the electrode surface and decreased its active plane, and, consequentry, the limiting current density was lowered. However, it contributed to the improvements of adhesion and stress in electrodeposit at the ruthenium deposition. Although the sodium acetate did not buffer a pH increase, it had an effect on getting a fine crystal plane of ruthenium as a bath component. The mixture of three components gave remarkable effects for the improvement of stress in electrodeposit, adhesion, and smoothing.

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Superfine magnetite particles were prepared from iron(III) hydroxide sols in the presence of iron powder and hydrochloric acid. The preparation process was separated into two steps; the preparation of superfine iron(III) hydroxide sol particles and the preparation of magnetite particles. As the first step, three kinds of iron (III) hydroxide sol particles(Sol A, B and C)were prepared as follows: Sol A was prepared by the addition of 0.018 mol⋅dm^-3 aqueous iron(III) chloride solution into boiling water and Sol C by the addition into the boiling water containing 1 wt% of a nonionic surfactant(PE-68). Sol A was further peptized by L-alanine and hydrochloric acid to prepare Sol B having good dispersibility. The diameters of sol particles of Sol A, B and C were 70±20, 70±20, 40±10 Å, respectively. As the second step, the fixed amounts of the iron(III) hydroxide sol particles(Sol A, B and C) prepared in the first step were added to the reaction products of iron powder(20 g) with hydrochloric acid. The total amount of the solution used for the reactions was 240 ml throughout the experiment. The amount of magnetite particles produced was almost propotional to the concentration of the iron(III) hydroxide sol particles, and the diameter of magnetite particles depended on the dispersibility of the sol particles used. It was found that the superfine particles of magnetite (diameter=50±10) were prepared from Sol C under following conditions: 20 g of iron powder and sol particles of which concentration was 4×10^-3⋅mol⋅dm^-3 were used in 240 ml of the solution with 100°C of reaction temperature and the reflux time being less than two minutes.

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The TiO₂ gels containing platinum and ruthenium were prepared by calcining hydrogels made by the hydrolysis of the mixture composed of titanium(IV) oxide hydrosol obtained from titanium (IV) chloride, hydrogen hexachloroplatinate (4-), ruthenium (III) chloride hydrate, and of various alkali hydroxides.
It was found that in the pres ence of the gels, the irradiation of 500 W high-pressure Hg lamp on a methanol-water mixture resulted in the evolution of gaseous hydrogen. The hydrogen evolution rate was dependent upon the amount and the sort of alkali hydroxides used in the preparation of the gels. X-ray diffraction studies revealed that the fractions of microcrystalline anatase- and rutile-type modifications formed in TiO₂ gels were varied with the alkali hydroxides.
It was also found that photocatalytic activities of the gels thus prepared could be correlated with the fraction of anatase.

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The regioselectivity of catalytic hydroalumination of isoprene with LiAIH₄ has been investigated. The hydrolysis of catalytic hydroalumination products gave 2-methylbutane[1], 3-methyl-1-butene [2], 2-methyl-l-butene [3] and 2-methyl-2-butene [4] in the pre sence of various transition metal chlorides (Table 1). [TiCl₂(cp)₂] showed the highest catalytic activity and selectivity for the formation of [3]. The selectivity for [3] increased up to 76% with an increase in the molar ratio of isoprene to LiAIH₄ ([Isoprene]/[LiAIH₄]) (Table 2). It was found that the steric bulk of alkenyl- and alkyl-aluminium hydride inter mediates was responsible for the selective formation of [3] during the catalytic hydroalu mination of i soprene with [TiCl₂(cp)₂] (Figs.2-4).

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A new process that improves corrosion resistance of fine acicular iron particles for magnetic recording media is described.
To improve the corrosion resistance of iron particles in a humid air atmosphere, iron particles are oxidized by bubbling air into toluene suspension of iron particles. Saturation magnetizations of the particles obtained by this treatment decrease linearly with logarithm of oxidation time. Moreover, the decreasing rate of saturation magnetization increases with rising oxidation temperature. A spinel iron oxide layer is formed on the surface of the iron particles by oxidation in toluene. It has been estimated that this oxide layer is 2-3 nm thick.
The corrosion resistance of the iron particles was examined by loss of their saturation magnetization when the particles were exposed in a humid air atmosphere of 60°C and 90% R. H. The lower the saturation magnetization of iron particles obtained by oxidation in toluene is, the more the corrosion resistance of the particles is improved because of the thicker oxide layer on their surfaces. Iron particles with the most improved corrosion resistance are obtained by oxidation at 90°C in toluene. Corrosion products formed in the humid air atmosphere are a mixture of α-FeOOH and Fe(OH)₃. The amount of the corrosion products decreases when iron particles are oxidized in toluene.

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The suitable combination of chemical components was selected for the analysis of the concentration ratio matching method. The correlation number between two samples is obtained by the concentration ratio matching method. A new criterion to estimate the correlation numbers is proposed. A value of correlation number which exceeds the referential value obtained in a common aquifer is supposed to show a high correlation. In order to select suitable combination of chemical components for the analysis, logarithmic correlation coefficients among the concentrations of chemical components in the sample waters were compared. High correlations were found among all of the major chemical components (Na, Mg, Ca, Cl, etc. ). On the other hand, high correlations were not found among all of the minor chemical components (Al, As, Sm, Mn, W, V, Rn). The major chemical component group and the minor chemical component group were analyzed by the concentration ratio matching method, respectively, and the correlation numbers among samples were compared. Most of the high correlation pairs for the major chemical component group were found in near wells, or in the wells which have same strainer heights above sea. However, this result was not found for the minor chemical component group. Themajor chemical components were suitable indicators to express the relations between aquifers. These results also suggest that the correlation number in a common aquifer can be a referential number.

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Fluorescein and its derivatives (2, 7-, 4, 5-, 1, 2, 7, 8-halogeno-fluorescein; mercurochrome; 4, 5-bis(acetoxymercurio)fluorescein exhibit intense fluorescence and/or phosphorescence, but 3, 4, 5, 6-tetrahydroxyxanthenes such as Pyrogallol Red and Bromopyrogallol Red do not exhibit any luminescence. Excited singlet state and triplet state properties of 6-hydroxy-3Hxanthen3-ones were studied kinetically. The spectra of absorption, fluorescence, low temperature phosphorescence at 77 K (LTP), room, temperature phosphorescence (RTP) and thermally activated delayed fluorescence (TADF) were measured. Quantum efficiency of intersystem crossing, radiative rate constant of fluorescence (kf) and non radiative rate constant (kg) were deduced from the values of quantum efficiency of fluorescence (φf) and lifetime (τf). Rate constant of phosphorescence (kp) was calculated from Arrhenius′ equation, namely plot of ln(TADF/RTP) against the reciprocal of temperature. On the basis of these luminescence properties, the following three main results were obtained: (1) Chemical species in excited state of hydroxyxanthenones could be identified. (2) For halogenated fluoresceins containing the atoms of bromine, iodine and mercury, LTP, RTP and TADF, whose radiation processes pass through the lowest triplet state, were more predominant emission than fluorescence because of enhancement of intersystem crossing by internal heavy atoms. (3) New analytical methods of xanthene dyes were designed by the combinatio n of Of, fluorescence sensitivity index (FSI), rate constant of phosphorescence (kp), RTP an d TADF.

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An amperometric titration for the determination of selenate and both of selenite and selenate in the mixture was investigated. In order to detect the end point, the oxidation current of thiosulfate ion(titrant) at a rotating platinum electrode(2000 rpm) was measured at +O.75 V vs. SCE. Selenate was reduced with hydrochloric acid to selenite, which could b e titrated with sodium thiosulfate in the presence of hydrochloric acid. Therefore, two titrations before and after the reduction gave the amount of selenite and the sum of selenite and selenate, respectively.
(1) Determ ination of sodium selenate: Ten cm³ of sample solution containing 2-47 mg of sodium selenate was introduced into the titration cell, and the solution was boiled for 6-4 min after the addition of 10 cm³ of concentrated hydrochloric acid. The solution w as cooled to room temperature, and 10 cm³ of 10 mol⋅dm^-3 hydrochloric acid and water we re added to make the total volume up to 50 cm³. The resultant solution was titrated w ith 0.05 cm³ portions of 10^-1 mol⋅dm^-3 sodium thiosulfate standard solution at intervals of 5 s (O.05 cm³/5s). Sodium selenate was determined with a relative error and a coefficient of variation less than 0.1% at its amounts from 2 mg to 47 mg.
(2) Differential determination of selenite and selenate in mixtures: A mixture containing 5 cm³ each of 10^-2 mol⋅dm^-3 selenious acid and 10^-2 mol⋅dm^-3 sodium selenate was analyzed by two aliquots. One aliquot was used to titrate selenious acid with 10-' moldm-3 sodium thiosulfate standard solution(0.05 cm³/5s) at room temperature after the addition of 20 cm³of 10 mol⋅dm^-3 hydrochloric acid and water to make the volume up to 50 cm³. Another aliquot was used to titrate the sum of selenious acid and sodium selenate in the same manner as described in (1). The amount of sodium selenate was estimated from the difference of the two titrations. Mixtures containing selenious acid and sodium selenate, from 1: O.5to 1: 40, were analyzed with a relative error and a coefficient of variation less than 0.3%. The effect of concomitant compounds was examined.

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Chemically modified enzyme membrane electrode was prepared by cross-linking laccase(EC 1.10.3.2) with bovine serum albumin using glutaraldehyde through amino group s on the surface of a RVC(reticulated vitrious carbon) electrode impregnated with epoxy resin. Response characteristics of the enzyme electrode for substrates(hydroquinone, p-phenylenediamine, norepinephrine, ethamsylate, etc. ) were investigated. The concentration of oxidized form produced by the enzyme reaction(benzenediol 1/2 O₂→benzoquinone H₂O) was measured by amperometry at -0.1 V vs. SCE. The electrode was operated in a phosphate buffer solution(pH 5.5); the response time was less than 5 s in a stirred solution(1430rpm) at 30°C. The linear relationship between the response and the substrate concentration was obtained in the concentration range 10^-7-10^-4 mol⋅dm^-3; this high sensitivity strongly suggested the occurrence of chemical amplification(10-20 times) due to the cycle of substrates caused by enzymatic and electrochemical reactions. Laccase immobilized on the electrode surface was relatively stable and retained about 65% of the initial activities even after repetitive use for 2 months, being stored in a phosphate buffer solution(pH 6.0) at 5°C when not in use. The enzyme electrode were applied to the determination of norepinephrine and ethamsylate in drugs and the results indicated that the electrode had high sensitivity and satisfactory precision(RSD<2%). Furthermore, it was found that the presence of ascorbic acid did not interfere with this measurement.

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A suspension of mixed hydroxide, which was prepared by mixing 5 ml of 1.0 mol/l ammonium iron(III) sulfate, 5 ml of 1.0 mol/l bismuth(III) chloride and 5 ml of 10 mol/l sodium hydroxide, was added to the sample solution containing not more than 20μg of chromium(VI). After adjustment of the pH of the solution to 6.0, the suspension was stirred for 60 min and the precipitate was filtered through a 0.45μm membrane filter. The precipitate on the filter was dissolved in 2.5 ml of 10 mol/l orthophosphoric acid. The pH of the resultant solution was adjusted to 6.0 with sodium hydroxide to precipitate iron(III) phosphate. The precipitate was filtered off through a 0.45μg membrane filter and the residue was washed twice with 2 ml of distilled water. The washings were combined with the filtrate and the total volume was made up to 20 ml with distilled water. The pH of the solution was adjusted to 2 with sulfuric acid and diphenylcarbazide was added to it. After standing for 60 min at 10°C, the absorbance was measured at 540 nm against reagent blank. As much as 0.2 mg of Pb^II, Cu^II, Hg^II, Zn^II, Ni^II, Mn^II, Cd^II, Co^II, Al^III, As^III, Mop and V^V, and as much as 20 mg of Ba^II, Sr^II and Mg^II did not interfere with the determination of 20μg of chromium(VI). The recovery of chromium(VI) was more than 90%. The proposed procedure was applied to the determination of trace amounts of chromium (V) in water and seawater.

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Treatment of 9-bromo-1-methylfluorene [4] with dimethyl sulfide in acetone afforded dimethyl(1-methyl-9-fluorenyl)sulfonium bromide [5] which converted in ethanolic sodium hydroxide to 1-methyl-8-(methylthiomethyl)fluorene (7) via unstable S-yield [6]. The desulfurization of [7] with Raney Ni in ethanol gave 1, 8 -dimethylfluorene [8], which was oxidized to 1, 8-dimethylfluorenone [1].9-Aryl-1, 8-dimethylfluorenes (9-(o-toly1)[12], 9-(m-tolyl)- [13] and 9-(2-methyl-1-naphthyl)-1, 8-dimethylfluorene [14] were synthesized by the reaction of [1] with corresponding aryllithium followed by the reduction with hydroiodic acid, respectively. Rotation barriers in [12] have been investigated by means of the DNMR method, and activation paramAers of [14] were obtained from the rate constants of the isomerization of rotamers. The free energy values of activation (ΔG) for the process of ap_??_sp were found to be ΔG ([12] ap→[12]sp) =19.7 kcal/mol, ΔG ([12]sp→[12]ap) =20.0 kcal/mol, ΔG([14]ap→[14]sp) =34.1 kcal/mol and ΔG ([14]sp→[14]ap) =33.8 kcal/mol, respectively. These results were compared with those of 9-(o-toly1), fluorene [15] and 1-methyl-9-(o-tolyl)fluorene [16].

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Gallium was heated with excess of magnesium and methyl iodide in a series of aliphatic and aromatic ethers, and the effect of solvent on the formation of trimethylgallium via alkyl transfer was investigated. The conversion was markedly dependent on the reaction temperature; the most satisfactory results were obtained when ethers boiling at around 140°C were used. The reaction was quite sluggish in lower-boiling (<100°C) ethers, while the use of higher-boiling (>150°C) ones led to a decrease in yield. Of 19 ethers examined, dibutyl ether was found to give the best results. Aromatic ethers could not be used as solvent, since they brought about extensive side reactions.

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The oxidation of Yallourn coal (C 66.8%d. a. f.) and the intermediates (water-insoluble acids, water-soluble aromatic acids, and residual coal) was studied as the first s tep for elucidating the mechanism of the formation of oxalic acid.
Yallourn coal contained oxygen as hydroxyl (10.3%d. a. f.), carboxyl (5.7%d. a. f.), and carbonyl (3.2%d. a. f.), and so the high reactivity was expected (Table 2). Residual coal and water-insoluble acids decreased rapidly with prolonging the oxidation time, and the maximal conversions to water-soluble aromatic acids (28%) and to volatile acids (23%), mainly acetic acid, were obtained after 15 min. Both oxalic acid and CO, increased with prolonging the oxidation time The initial rate of the oxidation was very high, and the conversion to CO₂ after 15 min was nearly one-half of that after 2 hours (Fig.1).
In the oxidation of the intermediates, high conversions to oxalic a cid were obtained, and the highest was 46% for water-insoluble acids. The conversion ratio of oxalic acid to CO₂ was nearly unity for all intermediates (Table 3). Oxalic acid was oxidized above 275°C, but it was stable in the NaOH concentration range of 1 to 25 mol⋅kg^-1 (Figs.5 and 6). After the oxidation of intermediates, mass spectra of the corresponding intermediates became simple. Therefore, it was considered that the changes of patterns of the spectra related to the formation of oxalic acid from water-soluble aromatic acids formed from residual coal (Figs.7, 9, 10, and 11).
The conversions to oxalic acid were 54.2, 47.8, and 75.4% in the oxidation of 1, 2, 4-benzenetricarboxylic acid, 1, 2, 4, 5-benzenetetracarboxylic acid, and acetic acid, respectively.
The reaction was assumed to proceed by the mechanism of base-catalyzed autoxidation, and the formation process of oxalic acid in the oxidation of Yallourn coal was proposed (Fig.12).

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The racemic structures of methylammonium (MA), ethylammonium (EA), and 1, 1, 3, 3tetramethylbutylammonium (TMB) salts of N-acetyl-DL--phenylalanine were studied. The binary phase diagrams of melting point indicate that these DL-salts form a racemic compound. However, since the mole fractions of L-EA and TMB salts at eutectic points are around 0.55, the racemic structures of these DL-salts are probably unstable near at room temperature. The transformation of racemic structure could be assumed in DL-EA and TMB salts since the free energies of formation of racemic compound was positive at 10°C. The infrared spectra and the data of solubilities supported that DL-EA and TMB salts exist as racemic mixture in the vicinity of room temperature, but not as racemic compound. The optical resolutions by preferential crystallization of these DL-salts were attempted at 10°C in ethanol. It was found that DL-EA and TMB salts can be resolved with optical purity higher than 90% (L-salts). The above results clearly indicate that DL-EA and TMB salts form racemic compound in the vicinity of melting point, but exist as racemic mixture in the vicinity of room temperature.

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The electric conduction in wholly aromatic polyamides was investigated. The Arrhenius plots of conductivity in poly(m-phenylene isophthalamide)(PrIA) and, poly(p-phenyleneterephthalamide)(PPTA) gave the concave curves which could be approximated by the two straight lines in each case (Fig.1). The activation energies of conduction were obtained as 105 and 25 kJ⋅mo1^-1 in the high and low temperature regions, respectively. The temperature dependences of conductivity in PPIA at higher temperature was similar to that in aliphatic polyamide, the carrier of which is considered to be protonic (Fig.2). In humid atmosphere, the conductivity at higher temperature was higher than that in dry atmosphere. At lower temperature, the conductivity was not sensitive to the humidity of atmosphere (Fig.3). These facts revealed that ionic process was predominant in higher temperature region. Temperature dependence of photocurrent is shown in Fig.6. The activation energy was very close to that of dark current at lower temperature. In addition to this result, the dependence of photocurrent on intensity of irradiated light (Fig.7) showed that the electronic conduction process was predominant in lower temperature region.

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Catalysts composed of manganese compound, amine, and alcohol were prepared and the influence of the components on catalytic activity for the oxidative polymerization of 2, 6-xylenol was studied.
Primary amine, of which pKa is higher than 9, was shown to -be effective as a ligand of the ternary complex catalyst. The molecular weight of the obtained polymer depended on the molecular structure of the amine; bulky amine was less effective and amine capable to chelate with manganese was more effective. Furthermore, not only N, N type chelate-forming amine but also N, 0 type one such as 2-aminoethanol were found to be highly effective for the formation of high molecular weight polymer. Alcohol was ascertained to be indispensable for high catalytic activity. Bulky alcohol such as t-butyl alcohol was, ineffective while methanol, ethanol, ethylene glycol, and 2-methoxyethanol were all effective. Any manga nese compounds soluble in methanol were applicable as a manganese component of the complex catalyst. The difference between manganese(II) chloride and manganese(II) acetate could not be observed as significant on the variation of the [η] of the polym_er with reaction time These results suggested that hydroxyl group of 2-aminoethanol and methanol may be coordinate to manganese.

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In order to identify the reaction products of protein fibers with aryl glycidyl ethers, amino acids in the hydrolyzates of the silk and wool fibers which had been treated with phenyl and p-tolyl glycidyl ethers (PGE, 2, 3-epoxypropyl phenyl ether and TGE, 2, 3-epoxypropyl p-tolyl ether) were converted to the butyl esters of the N(0)-trifluoroacetyl and N (0)heptafluorobutyryl derivatives and analyzed by gas chromatography-mass spectrometry on an OV-17 column. The results are summarized as follows. ( 1 ) Adducts of aryl glycidyl ethers with tyrosine, serine, cysteine and lysine were identified in the hydrolyzates: 0(Aryloxyhydroxypropyl)tyrosines were found in all the samples as major products.0(Aryloxyhydroxypropyl) serines were found in all the samples except for the silk fibers treated with PGE. S-(Phenoxyhydroxypropyl)cysteine was found in the wool fibers treated with PGE by a single ion monitoring method. N^ε-(p-Tolyloxyhydroxypropyl)- and N^ε, N^εbis(aryloxyhydroxypropyl)lysines were also identified in the silk and wool fibers treated with TGE and in the wool fibers treated with PGE and TGE, respectively. By interpreting the mass spectral fragmentation, the structure of aryl glycidyl ether-lysine 2: 1 adduct could be assigned as N^ε, N^ε-bis(3-aryloxy-2-hydroxypropyl)lysine at least for the main component of the adduct peak. (2) TGE-glycine and TGE-alanine adducts were detected in the silk fibers treated with TGE, indicating that the amino groups of N-terminal amino acid residues of silk fibers react with aryl glycidyl ethers. (3) Aryl dihydroxypropyl ethers(I), (aryloxyhydroxypropyl)amines(II) and bis(aryloxyhydroxypropyl)amines(III) were found in the hydrolyzates other than chemically modified amino acids. The formation of I is considered to indicate that aspartic and glutamic acid residues can react with aryl glycidyl ethers. The formation of II and III may indicate that the aspargine and glutamine residues and/or arginine residue can react with aryl glycidyl ethers.

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Alkylphosphorylcholines, n-CmH_2m+1, OPO(O-)OCH₂CH₂N+(CH₃)₃ (m=10, 12, 14, 16, 18abbreviated as Cm-PC), [2] have been prepared in good yields by the reaction of 2-alkoxy1, 3, 2-dioxaphospholane 2-oxide with trimethylamine (in DMF 80°C, 48 h) according to the procedure of Chabrier.
Compounds [2] were obtained as monohydrates, which were slightly hygroscopic colorless crystals and soluble in water, ethanol, and chloroform, but insoluble in acetone, benzene, hexane, and ether. Phosphoryloc holines [2] showed surface-active properties: [2] lowered the surface tension of their aqueous solutions to 39-43 dynicm at CMC (γCMC); C16-PC and C13-PC had solubilization power for Orange OT much better than DBS and SDS. C₁₄-PC and C₁₃-PC possessed emulsifying properties better than SDS, but were inferior to DBS. Penetrating power of [2] decreased with increasing chain length of the alkyl group of [2]. C₁₂-PC had dispersin g properties approximately as good as DBS.
Compounds [2] and C₁₂-betaine were practically inactive against bacteria, E. coli and S. aureus, but were as effective as CTAB and PCP-Na in inhibiting the growth of a fungus, A. oryzae.

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p-(Perfluorononyl)phenyl isocyanate [6] was first prepared via Curtius rearrangement of p-(perfluorononyl)benzoyl azide. Cellophane and Nylon films were treated with [6] in refluxing benzene or dioxane in order to modify their surfaces. The modified Cellophane samples were found by elemental analyses to contain only 0.1% fluorine, whereas their ESCA determination revealed the high atom content ratio of fluorine to carbon up to 3/5. The elemental analysis of the modified Nylon films gave only a trace of the fluorine content, but the ESCA determination showed a definite atom content ratio of fluorine to carbon even though the ratio was about one fifth as low as that of the modified Cellophane. When the Nylon film was pretreated with concentrated aqueous ammonia, it could be modified in higher extent than the untreated Nylon film. It was therefore assumed that in the modification of the Nylon film under these conditions 6 would not react with the NH group of amide linkages but with a reactive site such as amino group of the polymer ends. The modified Cellophane and Nylon films (pretreated with aqueous ammonia) exhibited large contact angles up to 109° and 96° for water and up to 72° and 58° for 1-bromonaphthalene, respectively. It is concluded that 6 can modify the Cellophane and Nylon at their very surface region. The water vapor transmission rates of the modified Cellophane and Nylon films were also examined.

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In order to investigate the decomposition of sodium alkylbenzenesulfonates(LAS) and other surfactants with soils, a soil perfusion method has been applied. The degree of degradation of the surfactants was evaluated by measuring the amount of ferroin-reagent-active substance(FRAS) and/or of total organic carbon(TOC) in the perfusion fluid.
The following results were obtained:
1) The biodegradation of the surfacta nts started after adsorption on soils. The biodegradation rate was in the order SDS>A0S>>LAS>ABS. This result was consistent with that determined by die-away tests.
2) At high LAS conce ntrations (50 and 100 m g/l), the biodegradation occurred after some induction period, but further added LAS was readily degraded without induction period.
3) The degradability of LAS was affected by its alkyl-chain length. Although the period of acclimation of C12 LAS was longer than that of C10-13 LAS, nearly the same rates of degradation were observed for both LAS's.
4) The period of disappearance o f FRAS was shorter than that of TOC: at 50 m e of LAS, total FRAS disappeared in 10 days, but TOC disappeared in about 50 days.
5) The disappearance of LAS in the soil perfusion was affected by the chemical and physical properties of soils. The amount of LAS adsorbed on the Koganei soil (clay loam)was larger than that on the Saku soil (sandy loam), and the biodegradation of LAS occured more readily in the former soil.

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For the growth of NdAl₃(BO₃)₄ crystals, BaB₄O₇ was chosen as a flux on the basis of the guide proposed by the authors.
NdAl₃(BO₃)₄ crystals were grown by slow cooling of BaB₄O₇ flux in which Nd₂O₃, Al₂O₃and B₂O₃ were dissolved as solutes. The growth was conducted by heating mixtures at 1150°C for 10 h followed by cooling to 600°C at a rate of 5°C/h. Crystals grown in BaB₄O₇ flux were hexagonal rod in shape, up to 7.1×1.5×0.7 mm in size, bluish purple in color and transparent. It was shown that the flux chosen was suitable for the growth of objective crystals.

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Isocyanic acid can be fixed quantitatively with an excess methanol solution of sodium methoxide or sodium hydroxide as sodium cyanate. Solubility of sodium cyanate in methanol-diethyl ether was measured. When volume ratio of methanol to diethyl ether was below 1/3, sodium cyanate was sparingly insoluble in the mixed solvent. Thus, sodium cyanate can be precipitated sufficiently adding three times volume of diethyl ether to that of methanol. After filtration of sodium cyanate, excess sodium methoxide or sodium hydroxide is titrated with O.1 mol⋅dm^-3 hydrochloric acid. The content of HNCO in the purified isocyanic acid was 99.4% or more by this method.

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Conductometric titration of organic halides such as benzyl chloride, benzoyl chloride and hydrogen chloride with EDTA were investigated in N, N-dimethylformamide(DMF). The observed molar ratio between these chlorides and EDTA was 1: 1.
But use of other solvents(DMSO, pyridine, etc.) did not give s ignificant inflection points. Less than 1 viv% of water gave no influence on this method, but the existence of chloride and metal ions gave positive error. The applicable concentration range of the method was about from 1×10^-3 mol⋅dm^-3 to 5×10^-2 mol⋅dm^-3.

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