The microwave spectra of propyl nitrite and its ₁₅N isotopic species were observed in a frequency range from 8.5 to 32 GHz. The ground state and vibrationally excited state spectra were assigned. They were found to correspond to a trans, gauche, trans form {τ₁(CO-NO) =180°, τ₂(CC-ON)=85.4°, τ₃(CC-00)=180°}. The following rotational constants for the ground state were determined:
The r₀ structure of propyl nitrite was derived from a least squares fit of these six rotational constants with reasonably assumed parameters for the propyl group as shown in table 6.

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MnO_x catalysts from MnCO₃ for a clean NO gas reduction with NH3 at low temperature around 150°C were prepared and the relation between the granulation conditions and mechanical strength, and that between the calcination conditions, activity, and surface excess oxagen of the catalysts were investigated by several physical and chemical methods.
The vacuum extruder type granulator gave a favorable catalyst o f higher crushing strength. The mechanical properties were affected by the amount of water and drying conditions. The addition of an appropriate amount of manganese nitrate solution to Al₂O₃ sol increases the crushing strength of the catalysts without decreasing their catalytic activity. The catalysts prepared by calcination at 350°C of the granulated MnCO₃ with Al₂O₃ sol showed the highest activity, corresponding to the highest level of the surface excess oxygen content measured by KI method at pH 7.1.
The suface excess oxy gen of catalyst was correlated to the catalytic activity of the above mentioned reaction. Pore volume with radius smaller than 100Å. also corresponded to the catalytic activity qualitatively. However, the specific surface area and active oxygen did not correspond well to the catalytic activity.

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The oxygen-sorptive and catalytic properties of defect perovskite-type oxide catalysts, La_1-xSr_xCoO_3-δ, have been investigated to disclose the origin of high catalytic activities of the compounds. Two types of sorbed oxygen a and β, were discerned from TPD chromatograms (Fig.1). The amounts of both α and β oxygen, which increased with increasing x, indicated that they were liberated from the oxide lattice: α oxygen is considered to be accomodated in the oxygen vacancies formed by the partial substitution of A site cations, while the desorption of β corresponds to the reduction of B site cations to lower valencies. It was found that both types of sorbed oxygen, α and β, were more reactive to hydrogen pulse than the rest of lattice oxygen though α was more active than β. Among the compounds with varying x, the maximum reactivity to hydrogen pulse was attained at x=0.4 (Fig.8), in agreement with the trend in catalytic activity for the butane oxidation (Fig.2). It is inferred that sorbed oxygen, especially a oxygen, is responsible for the high catalytic activities of the compounds. The change in catalytic activity with strontium substitution can be accounted for by the following two factors. One is the amount of a oxygen which increases with an increase in x, another the oxygen potential which decreases monotonously with x. Consequently, as a catalyst for oxidation reactions the control of these two factors is of importance.

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The single crystals of NbB₂, TaB and TaB₂ were prepared by the reaction of the metals and boron in molten aluminum under an argon atmosphere, and the conditions for obtaining them in single phase state examined.
The optimum mixing atomic ratios of raw materials, reaction temperature and reaction time are as follows: B/Nb=2.2, Al/Nb=51.6 for NbB₂; B/Ta=1.0, Al/Ta=100.5 for TaB; B/Ta=2.8, Al/Ta=100.5 for TaB₂; 1500°C for 10 h in any case. Under these conditions, NbB₂ and TaB₂ single crystals are obtained as hexagonal polyhedral enclosed with {1010}, {1010} and {0001} planes, and TaB single crystals in form of trapezoidal. The lattice constants and chemical compositions are as follow s:

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The effect of water treatment on the variation and stabilization of sulfur species in blastfurnace slag was investigated. It promoted the oxidation of sulfide and brought on the remarkable change in the distribution of sulfur species, almost suppressing the generation of yellow water(polysulfide ion) when it was immersed in water. The slag treated by air bubbling in water did not liberate, yolysulfide ions, too. These results suggest that oxygen in air promoted the oxidation of sulfides in slag to thiosulfates and sulfates in the presence of water, and that carbon dioxide in air caused the production of sparingly-soluble membrane of calcium salts(carbonate, sulfate) around the surface of slag. The generation of yellow water from new slag usually occured in stationary water, whereas it almost never occured in running water. It was found that calcium sulfide in slag dissolved as sulfide ion and gradually changed to, .. thiosulfate and sulfate ions in stationary water. On the other hand, calcium sulfidedissolNied mainly to produce thiosulfate ion and gradually changed to sulfate ion in running water.

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The optical resolutions by preferential crystallization of (±)-1-amino-2-propanol salts of organic acids have been studied. The salts employed were 2-aminobenzoate (2-AB salt), 4-hydroxybenzoate (4-HB salt), 4-methoxybenzoate (4-MTB salt), 4-methylbenzoate (4-MB salt), benzoate (BA salt), 4-chlorobenzoate (4-CB salt), 3-nitrobenzoate (3-NB salt), 4nitrobenzoate (4-NB salt), 5-sulfosalicylate (SS salt), and methanesulfonate (MS salt). The racemic structures of these (±)-salts at the melting points were determined on the basis of the energies of formation of racemate and the binary phase diagrams of melting point. The results indicated that (±)-3-NB and MS salts were conglomerate, and that (+)-4MTB salt was racemic solid solution. (±)-2-AB, 4-HB, 4-MB, BA, 4-CB, 4-NB, and SS salts formed racemic compounds. However, (±)-BA and 4-CB salts were suggested to be unstable racemic compounds at the melting points. The comparison of the infrared spectra and solubilities of (±)-BA and 4-CB salts with those of the corresponding (+)-salts, or the ternary phase diagrams of solubility at 10 and 30°C of 4-CB salt indicated that these (+)salts existed as conglomerate in the vicinity of room temperature. The optical resolutions by preferential crystallization of (±)-BA, 4-CB, 3-NB, and MS salts have been carried out at 10°C. Though (+)-BA and 4-CB salts with optical purity higher than 90% were obtained, the degrees of resolution were low. However, in the optical resolution of (±)-MS and 3NB salts, the (+)-MS salt with optical purity of 80.6% was obtained in degree of resolution of 54.8%, and (+)-3-NB salt with optical purity of 81∼93% in 43∼65%.

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Treatment of azoxybenzene [1] with AlCl₃ in CS₂ gave 4-chloroazobenzene [2] as main product, and azobenzene [3] and 4, 4'-dichloroazobenzene [4] as by-products (Table 1). The reaction of 2-chloro-ONN-azoxybenzene with AlCl₃ yielded a mixture of 2, 4- and 2, 4'-dichloroazobenzenes as the main products. Azobenzenes were chlorinated with AlCl₃ in the presense of azoxy compounds to give 4-chloroazobenzenes. It may be interpreted that dichloro azo cornpound [4] is formed by subsequent chlorination of the initial product [2] with AlCl₃ and the unchanged azoxy compound. The reaction of 4, 4'-dibromoazoxybenzene with AlCl₃ in CS₂ gave 4-bromo-4'-chloroazobenzene (18%) and 3, 4'-dibromo-4-chloroazobenzene (10%), together with 4, 4'-dibromoazobenzene (38%) and 4, 4'-dibromo-2-chloroazobenzene (19%). Meanwhile, [1] was treated with AlCl₃ in nitromethane to give [2] (60%) and [3] (18%), besides 2-hydroxyazobenzene (2%) and 4-hydroxyazobenzene (9%).

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In order to investigate the reaction mechanism of pyrolysis of 1-butanethiol, low pressure pyrolysis was undertaken at about 10^-3 Pa and below 1130 K (Table 1).
The parent peak intensity of the reactant observed with QPMS w as found to decrease at above 950 K (Fig.1). From the conversion of the reactant, unimolecular reaction rate constant k_uni was obtained as follows, where k_e was the escape rate constant and f was a cove rsion of the reactant.
k_uni thus obtained was found to depend on the reaction temperature and the collision frequency, and not on the pressure and the collision number (Fig.2). From the dependence of the collision frequency, this reaction was considered to be in the fall-off region under these conditions. From the independence of the pressure and the collision number, molecular collision and catalytic effect of reactor wall were considered to be negligible respectively, as expected. In proportion to the decrease of the reactant peak intensity, the intensity of some product peaks, which were assigned to ethylene, hydrogen sulfide and 1-butene, was found to increase (Fig.3). Following stoichiometry was obtained.
n-C₄H₉SH 1.7 C₂H₄+ 0.6 H₂S + 0.15 C₁H₅CH=CH₄
Compared with other experiments, which had been undertaken at higher pressure than the present experiment, and which had shown 1-butene to be the main product, the distinctive feature of low pressure pyrolysis of 1-butanethiol was considered to be the formation of ethylene. In order to explain the main product ethylene, following mechanism was proposed. Estimating the kinetic features of butyl and ethyl radicals based on the reported values, it was suggested that under these conditions butyl radical, once produced, selectively converted to two molecules of ethylene. Therefore, by assuming that 85% of initiation reaction was by means of C-S bond cleavage, the amount of ethylene produced could be explained. Based on the similar discussion, 1-butene was considered to be produced by molecular H₂S elimination.
Activation energy at 0 K obtained from RRKM calculation was 282∼287 kJ⋅mol^-1 (assuming collision efficiency 1) or 275∼281 kJ⋅mol^-1 (assuming collision efficiency dependent on tempera. ture) (Figs.4 and 5). These values seemed to be compatible with the above radical mechanism.

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In order to elucidate the degradation mechanism of polypropylene over activated carbon catalyst, reactions of the primary decomposed fragments of polypropylene with special regard to cracking reactions were investigated at 500°C using a pulse reactor system. The fragments used in this study were 2-methylpentane, 2-methyl-1-pentene, 4-methylheptane, 2, 4-dimethylheptane and 2, 4-dimethyl-1-heptene.
The cracking of the branched paraffins can be explained in terms of radical mechanism in which the abstraction of not only tertiary hydrogen atoms that are most loosely bonded to carbon atoms but also secondary and primary hydrogen atoms were considered. The experimentally observed distributions of cracking products are in fairly good agreement with those calculated on the basis of relative degree of the abstraction of three types of hydrogen atoms.
Branched olefins were much more labile than paraffins with the same carbon num bers. The distributions of cracking products from the both reactants were different from each other. The initial steps in catalytic cracking of branched olefins seem to be the abstraction of hydrogen atoms in the β-position with respect to a double bond and the addition of hydrogen atoms to a double bond at the catalyst surface, and the latter takes place predominantly when a large number of hydrogen atoms are held on the surface. Further, the migration of double bonds also occurred in reactions of branched 1-alkenes to yield 2-alkenes.
The activated carbon was also effective for the dehydroc yclizations of saturated and unsaturated fragments. m-Xylene and 1, 3, 5-trimethylbenzene were formed in reactions of 4methylheptane and 2, 4-dimethyl-1-heptene and its saturate, respectively. These dehydrocyclization reactions seem to be the main pathways producing aromatics in degradation of polypropylene over the catalyst.

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The optical resolution by preferential crystallization of organic ammonium salts of NacetylDL-α-phenylglycine, (DL-AcPhg), has been attempted. The organic ammonium salts employed were isopropylammonium salt (IPA salt), butylammonium salt (BA salt), isobutylammonium salt (IBA salt), pentylammonium salt (PTA salt), cyclohexylammonium salt (CHA salt), benzylammonium salt (BZA salt), dicyclohexylammonium salt (DCH salt), piperidinium salt (PI salt), and 4-methylpiperidinium salt (4-MP salt). The racemic structure of DL-salts were deternimed on the basis of the free energies of formation of racemate, the binary phase diagrams of melting point, and the comparison of infrared spectra of the DLsalts with those of the corresponding the D-salts. The results indicate that DL-CHA salt is racemic solid solution, and DL-BA, IBA, PTA, BZA, DCH, PI, and 4-MP salts form racemic compounds. However, it was suggested that DL-IPA salt is conglomerate in the vicinity of room temperature though the DL-salt forms at the melting point. The ternary phase diagram of solubility at 10°C in ethanol supported this suggestion. The optical resolution by preferential crystallization of DL-IPA salt was carried out at 10°C in ethanol. It was found that DL-IPA salt could be resolved into the D-salt with optical purity higher than 90%.

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The effects of additives on the assembled structure of lipids in liposomes, especially on the phase transition behaviour of phospholipids, were analyzed with differential scanning calorimetry and fluorescence depolarization techniques. Membrane proteins and lipid analogues were incorporated into dipalmitoyl phosphatidylcholine (DPPC) liposomes. Membrane proteins extracted from bovine erythrocytes showed strong suppressive effect on the transition behaviour. Glycolipids and cholesterol also showed suppressive effects but the efficiency of them was reduced gradually by the increase of additive amounts. The effects of lipid molecules having different alkyl chain length were also evaluated with the same techniques. No phase separation was observed in the hybrid liposome system composed of two kinds of lipids if the difference between numbers of carbon atoms in alkyl chain was two or less. Against this, a clear phase separation was observed in system for which the difference was more than four carbon atoms.

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Twenty two lariat ethers varying in the number of an oxyethylene unit and in the terminal group structure in the side arm were derived from 14-crown-4 bearing a long alkyl chain and two hydroxyl groups (Scheme 1).
The cloud point and the critical m icelle concentration (CMC) in water were determined for water-soluble compounds which have CH₃, OH, or CH₂COOH as a terminal group in the side arm (Table 1). The cloud point regularly rised with an increase in the number (n) of the ethereal oxygen in the side arm. From the n dependence of the cloud point, the hydrophilicity of the crown part (14-crown-4) containing one tertiary OH group was evaluated to be equivalent to that of three oxyethylene units in linear polyethers (Fig.1). Both the cloud point and CMC of the compounds rised with an increase in hydrophilicity of the terminal group in the side arm in the order of CH₃<OH<CH₂COOH.
In the Finkelstein reaction, the lariat ethers with n=3∼4 and the relatively hydrophobic terminal group in the side arm showed a markedly high activity as a phase transfer catalyst. Their catalytic efficiency was superior to that of dicyclohexano-18-crown-6 when NaI was used as an iodination reagent (Table 2).
The lariat ethers terminated with C OOH in the side arm actively transported alkali metal cations (Li⁺, Na⁺ and K⁺) in the chloroform liquid membrane system. The transport efficiency increased with an increase in lipophilicity of the lariat ethers used as a carrier. The ion-selectivity was significantly dependent on n, suggesting the cation complexation in a pseudo three-dimensional cavity which was constructed from the crown ring, the oligo (oxyethylene) side chain and the carboxylate anion cap (Table 3). A similar tendency was also observed in extraction of cations with the lariat ethers into chloroform (Table 4).

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It was possible to cast polyelectrolyte complexes (PEC) consisting of methyl glycol chitosan (MGC), (carboxymethyl)dextran (CMD), and poly(vinyl sulfate) (PVSK) into membranes. It was revealed that the PEC membranes exhibited active and selective transport behavior for alkali metal ions.
In the activ e transport, as H⁺ in acidic side transferred to basic side through the membrane by diffusion, the equivalent alkali metal ions in basic side were drawn into the acidic side (see Fig.1 and 3). Generally speaking, the active transport was driven by the disparity in the hydrogen ion concentration between both sides of the membrane. In addition, the transport ratio of K⁺ was larger than that of Na⁺
On the other hand, K⁺ was transported more rapidly than Na⁺ in the selective transport (see Fig.5). The selective transport was controlled by the radius of hydrated alkali metal ions and the affinity of carriers in the membrane for those ions.

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A new method for determining the quantum yield of photochemical reaction in solid photochromic films is proposed. Photochromic films were irradiated with monochromatic light of appropriate wavelength for a photochromic reaction, and the variation in the intensity of transmitted light was monitored. The quantum yield of photochemical reaction φ was evaluated from the equation:
where t is time, I_o and I_t are the intensities of transmitted light at t=0 and t=t respectively, I_n the intensity of transmitted light through the film without photochromic species, I_sr the intensity of incident light, γ the reflectance of a sample film, and ε the mo lar extinction coefficient of photochromic species. Poly(methyl methacrylate) films doped with α, α, δ-trimethyl-δ-(2, 5-dimethyl-3-furyl) fulgide were adopted for the verification of the method to determine the quantum yield. From the variations in the intensity of transmitted light with time (Fig.3), the linear plots based on the above equation were obtained (Fig.4). The quantum yield of photodecoloration of the fulgide in PMMA films was given as the equation:
φ=4.8×10^-4T(°C)+0.039

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Photofading of direct dye type fluorescent brightening agent (FBA), disodium 4, 4'bis(2-sulfonatostiryl)biphenyl, was studied in aqueous solution. The absorption and fluorescent spectrophotometry and thin-layer chromatography showed that the photofading process consisted of rapid initial reaction stage and subsequent slow one. The initial stage was reversible trans-cis isomerization, while the subsequent stage was a photooxidation. Kinetic analysis of the decay curve suggested that the reaction of the initial stage is unimolecular, accompanied by a bimolecular quenching.

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A method to determine the compositional fluctuations of (Ba, Pb) (Zr, Ti)O₃ (BPZT) solid solution was developed, and a new technique to synthesize the BPZT solid solution having no compositional fluctuations was designed.
Solid solutions of BPZT has two kinds of compositional fluctuations originating from Asite and B-site. Both compositional fluctuations were determined discretely, as follows. The fluctuation due to the variation of x was estimated through the fluctuation of the c-axis length, which was determined from a slope of the relation between β cos θ and sin θ of 00l diffractions, because the c-axis length does not depend on y, but on x in (Ba_xPb_1-x) (Zr_yTi_1-y)O₃. On the other hand, the fluctuation due to the variation of y was determined by measuring the fluctuation of the (h0h) interplanar spacing, which does not depend on x, but on y.
The BPZT solid solution, prepared by a solid state reaction among BaCO₃, PbO, ZrO₂ and TiO₂ by dry process, had large compositional fluctuations due to both A-site and B-si te. On the contrary, the BPZT solid solution, prepared by a solid-solid reaction between a coprecipitated barium and lead carbonates (BP) and that of zirconium and titanium (ZT) by wet-dry combination process, had no compositional fluctuations. Results of a high temperature X-ray diffractometry revealed that the reactivity of BPZT synthesized by the wet-dry combination process was good. The dielectric constant of BPZT prepared by the wet-dry combination process was high, and its diffraction peak at Curie point was very sharp.
The combinations of BP+ZrO₂+TiO₂, BaCO₃+PbO+ZT were also studied. B oth of them had a small compositonal fluctuations.

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Disappearance process of sodium alkylbenzenesulfonate (LAS) was examined by using the biodegradation test with soil perfusion method.
It was proved by HPLC analysis that the biodegradation rate and the adsorption amount of LAS were clearly dependent upon the alkyl chain length, as well as the position of the sulfophenyl group on the alkane chain: LAS disappeared rapidly with increasing alkyl chain length and isomers having sulfophenyl group near the end of the alkane chain disappeared more rapidly than those having sulfophenyl group in the middle part of the alkane chain.
The results of disappearance of C₁₂-LAS detected by HPLC were in fair agreement with those obtained by the measurement of the loss of the ferroin reagent active substances (FRAS). However, the results for C_10∼13-LAS determined by the two method did not agree with each other.
It was ob served that the disappearance of LAS adsorbed onto soil proceeded in a similar manner as in the case of LAS in perfusion fluid.

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Controlling factors of rhodium dispersion degree on supported rhodium catalysts for syngas conversion have been tested in terms of H₂ reduction temperature of catalyst, surface area of support, and loading amount of rhodium. Rhodium dispersion degree decreases remarkably at the reduction temperature between 350°C and 400°C. In addition, it decreases with an increase of loading amount of rhodium. However, rhodium dispersion degree is not changed remarkably by the surface area of supports in this work. It has been also suggested that catalyst preparation procedures such as pretreatments of supports, impregnation methods, and drying process before reduction are important for controlling rhodium dispersion degree.

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The interferences of chromium and manganese encountered in the spectrophotometric determination of vanadium in coal and coal fly ash were eliminated by the addition of EDTA as a masking reagent. The analytical values of NBS samples obtained by the improved method were all agreed with those certified by NBS. In coal, the correlation coefficient between vanadium concentration and ash contents was calculated to be O.90, which indicates that vanadium present in the coal is closely correlated to ash.

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In the diazonium thermosensitive systems, phloroglucinol and phlorogrucide were investigated as black developing couplers. Black-like dye images could be obtained by using either of them and a basic compound as a catalyst. The color development occurs via the evolution of water of crystallization of couplers. Phloroglucide, which has lower solubility in water than phloroglucinol, showed better shelf-life characteristics.

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Three kinds of diazonium tetraphenylborates (diazo TPB) were synthesized and their thermal stability was investigated. Thermal stability of 2, 5-dibutoxy-4-morpholinobenzenediazonium TPB was found to be high. Two salts, 2, 5-diethoxy-4-(4-methoxybenzoylamino)benzenediazonium TPB and 2, 5-diethoxy-4-(p-tolylthio)benzenediazonium TPB, were thermolabile and tarry matter was produced from them after a week of storage. The thermolability was dependent on the mixing ratio between aqueous solution of diazoniun zinc chloride and sodium TPB solution, and on the storage condition of the precipitate. Needle-like crystals were produced from the tarry matter of diazo TPB and it was identified with phenylboronic acid. The thermal decomposition occurs via the decomposition of TPB anion.

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Adsorption/desorption behavior of polycyclic aromatic hydrocabons (PAHs) in the atmosphere has been studied. Test pieces (4.7 cm diameter) were prepared by cutting out the glass fiber filter on which airborne particulates were collected. Air containing PAHs at various concentrations passed through the test pieces at 15 / /min for 48 h at ambient tempe rature (average temperature 9.1°C), and the amounts of PAHs in the test pieces were determined. In the case of PAHs which have high vapor pressure (10^-5≈10^-6 mmHg) such as fluoranthene. and pyrene, the amounts of PAHs in the test pieces increased linearly with increasing the concentrations of PAHs in the air passed and decreased when PAH-free air was passed. The adsorption of PAHs on particulates seemed to be reversible, and Langumuir adsorption isotherm in the low coverage would be applicable to the adsorption/desorption process of PAHs between vapor phase and particulate phase in the ambient air.

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In the presence of citrate ion as complexing agents, the adsorption of cobalt (II) and nickel (II) on titanium oxide from aqueous solution was studied over the range of pH 3∼9 in a batchwise operation. The initial concentration of cobalt(II) (or nickel(II)) in solution was varied from 2.5 mmolf/ to 50 mmol/l. The amounts of adsorbed cobalt(II) and nickel(II)increased with a rise in pH and showed maximum in citrate/Co(or Ni)=1 (molar ratio). The Langmuir equation was applicable to the adsorption of cobalt(II) and nickel(II). It was also shown that the saturated adsorption capacity were about 1.0 mmol Co/g and 0.7 mmol Ni/g.

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