Products from the thermal decomposition of iron(II) chloride were investigated in the temperature range between 250°C and 500°C and under various atmospheric humidities, in order to find the relationship between the reaction mechanism and the properties of the final product, a-Fe₂0₃. The color, the particle size, the particle shape, and the crystallite size of the resultant a-Fe₂0₈ were examined by use of reflectance curve of visible light, electron micrograph, and X-ray diffraction technique. The contents of decomposition products such as ce-Fe₂0₃, FeCIO, and FeCl₃ varied with total amount of H₂0 including crystal water. Thermal decomposition of FeCl₂ and FeCl₂4H₂0 proceeded in 2 or 3 stages. Large FeClO particles which were formed as an intermediate in a wet atmosphere gave large blackish violet a-Fe₂0₃ particles composed of grown crystallites. On the other hand, in a dry atmosphere small brownish red a-Fe₂O₃ particles composed of fine crystallites having many lattice defects were produced directly from FeCl₂.

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When powder hydroxyapatite (HAP) was heated below 650°C, the amount of adsorbed water released from HAP increased with increasing temperature without any degradation of the crystalline structure of HAP. On the other hand, when temperature was higher than 860°C, water was released from the OH-group of HAP, and -tricalcium bis (orthophosphate) (8-Ca₃(PO₄)₂) was formed via 3-calcium pyrophosphate (3-Ca₂P₂0₇). These facts were shown by the data of IR spectra and X-ray powder diffraction patterns, as shown in Figs.2 and 4.
At 900°C the content of crystallite in the HAP powder increased with time but at 1200°C it decreased, as shown in Fig.5, because the transition from amorphous HAP to crystallite HAP takes place to a great extent at 900°C, but the transition from crystallite HAP to 8-Ca₃(PO₄)₂ via B-Ca₂P₂0₇ takes place at 1200°C. The crystallite size of 3-Ca₃(PO₄)₂ increased with time upon heating at 900°C and 1200°C, but that of HAP increased first and then decreased during long heating at 1200°C because of the transition of HAP to 8-Ca, (PO₄)₂, as shown in Fig.7.
Change in IR spectra and the loss of weight of HAP by heating showed that HAP had a water content of 5.6%, even if treated at 120°C for 20 hrs., and that the activation energy for desorption of water was 1.26 kcal/mol. Comparison of this value with the activation energy observed in a higher temperature region above 860°C, 7.45 kcal/mol, showed that at the high tempetature the degradation of HAP structure occurred by the release of water vapour from the OH-group.

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NaHY type zeolites containing various amounts of sodium ion were evacuated and submitted to dielectric measurement at 100-400°C and in the frequency range 0.3-10⁶ Hz. For all the NaHY samples dielectric loss peak (Fig.1-B for NaY-86) was observed. Activation energy of the relaxation process changed with sodium content in the manner as shown in Fig.4. At 60% of the degree of exchange, the activation energy changed discontinuously. The loss peak frequency also changed with degree of exchange (Fig.5), and the relaxation peak was observed 'at high frequency side for the samples with high degree of exchange. It seems difficult to assume that the relaxation process is due to the migration of sodium cations between cation sites. Dielectric measurement was also carried out after deuterium oxide treatment, however, no isotopic effect was observed on the relaxation process. On the basis of the experiment of water readsorption (Fig.6, 7), the role of residual water was discussed.

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In a series of studies on electropainting mechanism, the electrochemical behavior of metal substrata was investigated. A stable acryl copolymer resin was electropainted anodically onto various metal substrata, such as Cr, Cu, Al, Sn, Zn, and steel, by the application of a comparative low cell-voltage (about 50 V). Then, the material or current balance was investigated by the chemical analysis of coated films or by the electrochemical observations, respectively.
Results obtained are as follows:
( 1 ) Metal substrata can be classified into following three types
( a ) Type of dissolving metal: Cr, Cu
( b ) Type of oxide film forming: Al, Sn
( c ) Type of dissolving and partially oxide film forming metal: Zn, steel.
( 2 ) The paint deposition on a metal substratum occurs in terms of proton production, resulting a decrease in pH of the solution in the vicinity of a substratum, due to an applied current.

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In a series of studies on electropainting mechanism, the acidity effect of paint resin on the anodic behavior of zinc coated steel sheet in paint solution was studied by using galvanostat. To observe the electropainting behavior, the potential change in anode upon passing constant current was measured by using an Ag/AgO reference electrode and a storage type oscilloscope.
It was found from those observations that:
( 1 ) Before paint deposition onto zinc coated steel sheet, 2 stages and one transition stage occur.
( 2 ) The first and second stages, which occur below 5 V (vs. Ag/AgO), before transition state, belong to surface preparing stages for paint deposition.
( 3 ) Transition stage, at which potential change from ca.5 to ca.10 V (vs. Ag/Ag0), upon passing constant current, corresponds to the passive film formation on a surface, caused by the combination of acryl copolymer resin with substratum.
( 4 ) The third stage, at which the gradient of I-E curves becomes lower than that of transition state, is the normal paint deposition stage.
( 5 ) A ratio of acrylic acid to acrylic ester closely relates to the end potential of the transition state, at which paint deposition starts. From a point of view of high speed electro- painting, the recommended ratio of acrylic acid to acrylic ester has been found to be 3:7-4:6
( 6 ) For the sake of corrosion resistance, a paint solution containing chromium ion has also been proposed.

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In a series of studies on electropainting mechanism, the electrodeposition of acrylic resin in paint solution onto zinc coated steel sheet has been studied by using potentiostat in a high potential region (±50 V). In this experiment, potential sweep method has been adopted to measure the anodic polarization (potential range: 0-500 V (vs. Ag/AgO)) of the specimen in 10% acrylic paint solution.
Results of this experiment are as follows:
( 1 ) First and second stages of electrodeposition process, before paint deposition, have been found to separate from anodic polarization curves of the specimen measured in paint solution; these had not been separated sharply by galvanostatic method in the former experiment.
( 2 ) The first stage concerns with the surface conditions of zinc coated steel sheet and the scond stage is affected by the amount of OH- ions surrounded the specimen.
( 3 ) Transition stage and third stage of electrodeposition process have also been observed on the anodic polarization curves.
( 4 ) Transition state, which has been observed as a constant current of low value on anodic polarization curves, is caused by the passive film formation due to the combination of paint resin with substratum.
( 5 ) The third stage, at which paint deposition occurs, was observed when the externally applied voltage overcomes the overvoltage necessary to form this passive film.
(6) The effect of Cr⁶⁺ ion on a new paint solution was estimated as an appearance of a new stage between first and second stages on polarization curve and as a decrease in third stage current in the high potential region.

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In order to understand the mechanism of the formation of organic compounds, especially amino acids, by the action of electric discharge, several experiments on simple gases (organic and inorganic) were carried out. The reaction system mainly investigated was CH₄-NH₃-H₂0 system. In addition to this system, three different experiments with CH₄ alone, with CH₄-NH₃ system, and with CH₄-H₂0 system were performed. In the experiment with CH₄ alone, the yield of unsaturated hydrocarbons was greater than that of saturated hydrocarbons. With the CH₄-H₂0 system, aldehydes were synthesized from alkynes. With the CH₄-NH₃ system, CN species such as HCN, CH₃CN, NH₄CN, and CH₂=CHCN were formed in large quantities in the reaction vessel. Amino nitriles were also formed directly by electric discharge, but the yield was very low. The relation between the products in gas phase and those in liquid phase was examined with CH₄-NH₃-H₂O system. In the gas phase reaction, amino nitriles were synthesized by the reaction from aldehydes formed from CH₄-H₂0, CN species formed from CH₄-NH₃, and NH₃. These products were changed into various compounds like amino acids by secondary reactions including hydrolysis in liquid phase.

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Submicrometre powders of Ti0₂-Si0₂ (0-40 mol%) were produced by the vapor phase reaction of the TiCl₄-SiCl₄-0₂ system at 800°C to 1400°C. Each particle of the powders was found to have the structure such that single-crystalline Ti0₂-particles dispersed in amorphous Si0₂ phase. The crystallite size of the Ti0₂-particles was 500 to 1000 A. Although the crystal type of TiO₂ was mainly anatase-form, the content of rutile-form increased with increasing reaction temperature and exhibited a maximum at a low SiC1₄ concentration. These results show that the growth and the transition of anatase to rutile of TiO₂ particles were suppressed by the codeposition of Si0₂ in the course of the formation of the Ti0₂-SiO₂ particles. The lattice constant, c_o, of anatase-TiO₂ increased with increasing reaction temperature and SiC1₄ concentration, indicating that Si0₂ dissolved in anatase phase whereas it does not dissolve in rutile phase.

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Reactions of iron (III) sulfate (0.0286-0.115 mol/l) with sodium sulfite (0.190-1.10 molg) both in the absence and presence of EDTA were investigated at temperatures between 25 and 85°C and pH between 0 and 10. Dithionate was quantitatively formed at pH above 2.0 in the absence of EDTA. However, the amount of sulfate formed simultaneously increased with the decrease of pH. The degree of reaction was rapidly decreased with the increase of pH at pH above 2.0, and the reaction did not proceed at pH above 5.7 even when the reaction temperature was elevated. On the other hand, iron (III) ion complexed with edta in the presence of it and reacted with sodium sulfite to form dithionate quantitatively at pH between 5 and 8. The rate of dithionate formation in the presence of EDTA was found to be first order with respect to hydrogensulfite and Fe (H) -edta and inversely first order with respect to Fe (II) edta. The apparent activation energy was found to be 21.3 kcal/mol. Further, the reaction of iron (III) sulfate with sodium sulfite in the presence of diethanolamine, ethylenediamine, nitrilotriacetic acid and 1, 10-phenanthroline was studied at pH 6.5. Dithionate was also formed in the presence of 1, 10-phenanthroline.

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Amorphous zirconium hydroxide was precipitated by the addition of aqueous ammonia to a ZrCl₂0 solution (O.1 mol/l). The precipitate was refluxed in distilled water, acidic (HO, HNO₃, H₂SO₄) and alkaline (KOH, NH₃) solutions at 100°C for 10-120 hours. The aged products were examined by means of X-ray diffractometry, electron microscopy and thermal analyses. The product aged in distilled water remained amorphous, although it had a smaller water content and a broader exothermic peak in DTA (differential thermal analysis) shifted to the higher temperature side. In heat treatments at 400°C in air, monoclinic Zr0₂ crystallized from the aged products, while tetragonal ZrO₂ from unaged zirconium hydroxide. In heat treatments under reduced pressure, tetragonal ZrO₂ crystallized from the aged products and it had broad X-ray diffraction peaks. These facts suggest that changes in the structure of the precipitate take place during aging in distilled water: from a-type structure composed of Zr-OH-Zr bonds to r-type structure composed of Zr-O-Zr bonds.
The aging in HCl and HNO₃ solutions of pH 1.0 gave the crystallization of monoclinic Zr0₂. Monoclinic Zr0₂ accompanied with tetragonal ZrO₂ crystallized at pH 1.4.
The aging in H₂SO₄ solutions of pH 1.0 led to the formation of the compound containing SO₄^2-.
The products aged in KOH and NH₃ solutions were amorphous. Tetragonal ZrO₂ crystallized in heat treatments at 600°C for 12 hours.

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An attempt to grow the high quality single crystals of NaLa(MnO₄)₂ was made by slow cooling of the high-temperature solutions of the ternary system La₂0₃-Mo0₃-Na₂CO₃ and an optimum composition range of the solutions was determined.
The crystals were grown under the following conditions: Soaking temperature: 1100°C, Soaking period: 5 hours, Cooling rate: 5°C/hr, Cooling range: 1100-400°C.
Results obtained were summarized as follows:
(1) NaLa(Mo0₄)₂ single crystals were grown by the flux method, using a mixture of La₂0₃ 2-15, Mo0₃ 53-89 and Na₂CO₃ 5-45 mol%.
(2) The single crystals, up to 4×4×4 mm³ in size, were colorless and transparent. The grown crystals exhibit ed {101} or {101}, {001} faces.
(3) Lattice constants of the crystals were a=5.343A, c=11.72A. Density of the crystals, picnometrically determined, was 4.76 g/cm³. This was in good agreement with the calculated value (4.78 g/cm³).
(4) According to DTA data, the crystals had a melting point of 1145°C.
(5) About 64 g of the crystal was dissolved in 100 g of Na₂MoO₄ flux at 1100°C. The solubility decreased with increasing addition of MoO₃ to the flux.

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Thermal decomposition reactions were investigated for the following eight cobalt (III) complexes coordinated with ethylenediaminetetraacetate (edta) K[Co(edta)]2H₂0, Na[CoBr(Hedta)]2H₂0, Na₂[CoCl (edta)]2H₂0, Na[Co(NO₂) (Hedta)]2H₂0, Na₂[CoBr(edta)]3H₂0, Na₂[C0Cl(edta)]6H₂0, H [CoBr(Hedta)]2H₂0 and H[CoCl(Hedta)]2H₂0. Central Co (III) ions were reduced to Co (II) ions by the decomposition reactions. The products obtained under the experimental conditions shown in Table 1 were reoxidized to Co (III) complexes, which were separated into -1, 0 and + 1 charged species by an ion exchange chromatographic technique. The -1 charged species was identified as Co(edta)^-. It was found that the non-charged species was composed of Co (III) complexes coordinated with ethylenediamine-N, NiNitriacetate (edtra) and/or N-methyl-substituted edtra as ligand (s), and that the +1 charged species was composed of the complexes coordinated with ethylenediaminediacetate (edda) and/ or N-methyl-substituted edda as ligand (s). Product distribution is summarized in Table 3. Nearly 50% of EDTA remained unchanged even after the complete reduction of CoM ions to Co(III) ions. This result suggests that an intermolecular electron transfer path contributes to the thermal decomposition reaction. The occurrence of so-called thermal chelation was also examined for each complex.

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A method has been established for the quantitative determination of infrared active gas in nitrogen by infrared absorption spectrophotometer, Systems treated in this paper are those in which methane, propane, carbon monoxide, or nitrogen oxide is contained in nitrogen as a sole component. It is experimentally confirmed that appropriate pressurizing of the sample gas and the use of an infrared spectrophotometer of high resolving power make the observed absorbance proportional to the product of the cell length and the partial pressure of the component gas.
The probable error which may occur in each process of the present method was rigorously estimated, and the total relative error in the analysis is calculated to be smaller than 1.9%. The pressure of 10 kg/cm² has proved to be sufficient to cause necessary pressure broadening. Other experimental conditions are listed in the following together with the obtained results:
It has also been proved that the disturbance from the adsorption is negligible for all kinds of component gas treated here, as long as the concentration is higher than the limit of determination listed above. It is concluded that the present method is suitable for the analysis of standard gas mixture used for the calibration of various analytical instruments designed for the analysis of air pollution.

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Complex formation reaction of a water-soluble porphyrin, a, R, T, 8-tetrakis(4-sulfopheny1)- porphine[T(4-SP)P], with palladium ( II ) was studied, and a new highly sensitive method for spectrophotometric determination of micro amounts of palladium has been developed utilizing the Soret band of the palladium ( II )-T (4-SP)P complex. The complex formation reaction in aqueous medium is very slow at room temperature, but it proceeds quantitatively at pH about 3.6 and a stable 1: 1 complex is formed when the solution is heated at about 100°C for 15 min. The Soret band of the complex lies at 410 nm, which was well separated from that of diacid form of T (4-SP)P (435 nm). A straight line calibration curve was obtained up to at least 360 ppb of palladium. Apparent molar absorption coefficient and sensitivity for 0.001 absorbance obtained from the calibration curve were 2.2x10⁵l.mol^-1.cm^-1 and O.48 ng Pd cm^-2, respectively. Interferences due to other ions and salts were examined and the tolerance limit was shown for each of them.

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A method is presented for determination of trace lead, based on co-precipitation with thorium hydroxide followed by flameless atomic absorption measurments. The combined method can be applied to the determination of a ppb level of lead in industrial waste water as well as a copper base alloy.
The following procedure is established: To a sample solution (100-2000 ml) containing O.5 to 5 pg of lead, 2 ml of thorium nitrate solution (10 mg Th/ml) is added. This solution is adjusted to pH 10 with aqueous ammonia and heated to 60°C. Then it is set aside for an hour. The precipitate is filtered through a Toyo No.5 A filter paper and is dissolved in 10 ml of 2 N nitric acid, and then the whole is diluted to 100 ml. An aliquot (10ul) is injected into the cavity of the carbon tube flameless atomizer.
The error was within 3%. It was only lanthanum among 41 diverse ions tested that interfered with the determination of lead.

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In the oligomerization of ethylene by Ni(acac), - (C₂I-15), A1, Cl, -phosphine or phosphite catalyst, the effect of phosphorus ligands on the oligomer distribution has been studied. In the sequence of tributylphosphine, triphenylphosphine, and tris(4-ehlorophenyl)phosphine, the proportion of butenes in the products decreased from 85.5% to 55.1%, and that of 3-methylpentenes increased from 11.9% to 32.5%. The results were interpreted in terms of the decrease of the electron donating power of the phosphines in the above sequence. In the case of phosphites (triphenyl phosphite, tri (2- and 4-tolyl) phosphite, and tri (2- and 4-biphenylyl) phosphite) which are considered to be weaker bases than tris(4-chlorophenyl) phosphine, the oligomerization products contained high percentage of butenes (77.2-95.8%). This means that the phosphites coordinate firmly to the nickel atom because of the little bulkiness or the small ligand cone angles, and consequently behave as strongly electron donating ligands.

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Typical enimides such as N-vinylphthalimide 1, N-vinyl-o-sulfobenzimide (2), N-vinylsuccinimide 3, N-vinylcamphorimide [9], N-styrylphthalimide 10, cis- and trans-N, N'- vinylenediphthalimide 11 and [12] have been subjected to the following reactions on their vinyl and carbonyl groups with purpose of developing their synthetic uses. The Vilsmeier reaction on the vinyl group of 1 and 2 afforded N-(2-formylvinyl)imides, [6] and 7 (Table 1 and 2). Oxidation of 1-0 and 9, -12 with Mn(OAc)8 in acetic acid afforded imido-substituted butyrolactones, 13 19 (Table 3). The Grignard reaction on the carbonyl group of [1 ], [3] and [10] afforded N-vinyl hydroxy lactams (N-vinyl-3- hydroxy-1-isoindolinoes or N-vinyl-5-hydroxy-2-pyrrolidones), [20]-25 (Table 4 and 5). The Wittig reaction of [1], [3], (6) and [10] with triphenyl(ethoxycarbonylmethylene) phosphorane afforded N-vinyl-5-methylenelactams, [26]30 (Table 6). Reaction of 1, [2] and (3) with benzene in the presence of palladium in salt afforded 8-phenylated products, 10 and [33], and/or 1, 4-bis(imido)butadienes (dimerized products), 31 and [32] (Table 7).

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The Diels-Alder reactions of three N-methyl-2-pyridones with maleimide or N-phenylmaleimide gave six 2-methyl-3-oxo-2-azabicyclo[2.2.2]oct-7-ene-endo-5, 6-dicarboximides (endo adducts) and four exo isomers. The main factor of differences in chemical shifts between endo adducts and exo isomers was assumed to be due to the magnetic anisotropy of those unsaturated double bonds. This was confirmed by the comparison of PMR data of those products with those of reduction products of 7-8 double bonds. Endo adducts were obtained in higher yields at lower temperature than at about 130°C, while a small amount of exo isomers was obtained at slightly above 130°C. The thermal stability of Diels-Alder products and of the products of these reactions was analysed by PMR and TLC; thus, overall aspects of these reactions were elucidated. Yield of endo adducts was lowered when acetic acid, a appreciable polar solvent, was used. This was a rare case of Diels-Alder reactions.

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The effects of the addition of NH₃ on the disproportionation of olefins catalyzed by WO₃SiO₂ have been studied in a flow reactor. The rates of the addition of NH₃ were 100-600 ml/hr NTP for 20 l/hr NTP of olefins. The disproportionation of olefins was promoted and the isomerization was inhibited by the addition of NH₃, the selectivity for the former reaction being significantly improved. The effects of added NH₃ are, however, not simple and are dependent on reactant olefins. The disproportionation of 1-butene was slightly promoted by the addition of NH₃, but in some cases, it was rather suppressed by NH₃. The dispropor- tionation of propylene and the reaction of trans-2-butene with isobutylene were considerably promoted by the addition of NH₃. In the reaction of propylene with isobutylene, propylene-propylene metathesis was fairly promoted, propylene-isobutylene metathesis was slightly pro- moted, and isobutylene-isobutylene metathesis was practically not affected by NH₃. Propylene and isoamylenes were produced very selectively by the reaction of trans-2-butene with iso- butylene catalyzed by W0₃-K₂0-Si0₂ and NH₃. In many cases, temporary acceleration of the disproportionation was observed at a few minutes after the stop of the addition. This accele. ration suggests that NH₃ has a promoting action on the activity of the catalyst for olefin disproportionation and an inhibitive action on the reaction at the same time.

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Solvent induced shifts of the methoxyl protons in polymethoxy-1, 4- naphthoquinones are reported (Table 1). The isolated methoxyl group at C-2 in mono- and disubstituted 1, 4-naphthoquinones exhibits a large Δ value (0.97-1.03 ppm). The 4 values of those at C-5 (or 8) and C-6 (or 7) are 0.70-0.75 ppm and 0.810.85 ppm, respectively. On the other hand, the methoxyl group at C-5 accompanied by the ortho-methoxyl group (C-6) shows a small Δ value (0.11 ppm). The solvent Shifts in trimethoxy-1, 4-naphthoquinones arc shown to be similar to those in the corresponding mono- and disubstituted compounds.
The benzene-induced NMR shift technique is thus a useful aid for the structural elucidation of similar quinones.

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The copolymers of 4-vinylpyridine (4 VP) with styrene or methyl methacrylate were prepared. The electrical conductive composites were prepared by dispersing N-methylacridinium-TCNQ complex salt (MA CQ₂) into these copolymers. The properties of the composites, such as conductivity, stability, and uniformity, were studied giving attention to the 4 VP composition in the copolymer.
Uniform flilms of the composites were obtained when the 4 VP composition in the copolymers was high. The phase separation of MA CQ₂^- was observed with the naked eye in the 4 VP-styrene system, when the 4 VP molar fraction became O.52. On the contrary, the conductivity and the stability of the composites became high with decreasing the amount of the copolymers or 4 VP composition in the copolymers. It was found that MA CQ₂^- became incorporated into the copolymers with a support of 4 VP moiety, and that 4 VP moiety lowered the conductivity and stability of the composites. This effect can be attributed to the chargetransfer interaction which occurs between MA CQ₂^- and 4 VP moiety.

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The relation between thermal dehydrochlorination and polymerization of cyano groups in poly (a-chloroacrylonitrile) (PCAN) was investigated by using the sample, heated under nitrogen atmosphere at an elevation rate of 5°C/min.
Although the degradation of PCAN is a complicated reaction, it was proved that a degree of degradation can be approximately calculated by a degree of decay in absorbance intensity at 500 cm^-1 in infrared absorption spectra. On the basis of the comparison between the degree of degradation and that of dehydrochlorination, the following results were obtained. ( 1 ) When it was heated up to 215°C, the degree of dehydrochlorination was 13.3% but the percentage of the repeated runs, which were subjected to polymerization of cyano groups, became more than 36%. ( 2 ) Although a rapid dehydrochlorination was observed above 215°C, the reaction proceeds mainly in the moiety which has been already subjected to polymerization of cyano groups.
On the other hand, in the partially dehydrochlorinated PCAN (its degree of dehydrochlorination being 28.4%), obtained by treating it with triethylamine, the dehydrochlorination began at ca.160°C and, when it was heated up to 200°C, the degree of dehydrochlorination became 57.1%, but the thermal polymerization of cyano groups was not observed at ca.200°C.
Consequently, it was concluded that PCAN is easily subjected to thermal polymerization of cyano groups at ca.200°C, if the previously dehydrochlorinated moiety does not exist, and further, the moiety, subjected to such polymerization, is more easily dehydrochlorinated than the original PCAN.

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In order to clarify the adsorption site of NH, on Cu (II)-exchanged Y-type zeolite (SK 40- Cu), upon which NH₃ is markedly adsorbed under the coexistence of water vapor, and NO is easily reduced by NH₃ at lower temperatures. The temperature-programed desorption and infrared absorption spectra were examined.
The adsorption and the desorption of NH3 were carried out by using a thermobalance under an atmospheric pressure and at 90-500°C. In the adsorption, the inlet gas was the mixture of NH3(0.1 or 1%), H20(0 or 12%), and N₂, and the total gas flow rate was 500 Ncm³/min for 500 mg of adsorbent with average dia. of 1.0 mm. In the desorption, the inlet gas was pure N₂, the total flow gas rate was the same as above and the rate of temperature rise was 2.5°C/min.
The following results were obtained:
1 Among the adsorption sites of NH₃ on SK 40-Cu, three kinds of site exist: the site for physical adsorption, Cu²⁺ site for forming Cu (NH₃)4²⁺, and OH⁺ site for forming NH₄⁺
2The adsorption due to the formation of Cu(NH₃)₄²⁺ is markedly influenced by NH₃ concentration. At lower NH₃ concentration, the adsorption of NH₃ on OH⁺site becomes pre-dominant.
3 The adsorption of NH₃ on OH⁺ site occurs markedly at higher temperature than 200°C. It is presumed that the reduction of NO by NH₃, which proceeds easily over SK 40-Cu catalyst at ca.200°C, is closely related to OH⁺ site.
4 The OH⁺ site consists of two kinds, i. e., Cu(OH⁺) and Al(OH⁺), and the amount of NH₃ adsorbed on each site varies with the method of ion exchange of Cu (II).
5 As to the Cu(II)-exchanged A-type zeolite(ML 5 P-Cu), only an adsorption of NH₃ on OH⁺ site was detected.

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Equilibrium diagrams between partial pressure of NO and concentration of Fe(II) (NO)-edta were made in order to elucidate the mechanism of adsorption and desorption of NO in Fe (II)-edta solution. The equilibrium is dependent on temperature and the heat of formation for nitrosyl complex was calculated to be -14. 1 kcal/mol.
The absorption rate of NO in Fe (II) -edta solution was determined by using wetted wall column. The overall mass transfer coefficient based on gas phase (K_G) is influenced by Rey-nolds number of gas {(Re)_o} and not by liquid flow rate (L). The overall mass transfer coefficient based on liquid phase (K_L) is not influenced by Reynolds number of liquid {(Re)_L} when the vacant molar velocity of ga (Gm) is constant.
Then, the absorption rate of NO in Fe(II)-edta solution is expressed by the following equation : K_G=0.068 G_M, where the temperature being 50±3°C, the concentration of Fe(II)-edta being 0.08-0.34 kg-mol/m³, the partial pressure of NO being 100-200 x 10^-6atm, (Re)_G being 1000-3000, and L being 2.0-3.7/hr.
The rate-determining step of the absorption was assumed to ascribe to gas-film under above conditions.
The oxidation rate of Fe(II)-edta by oxygen was determined by using the same colum.The oxidation rate was found to be directly proportional to the partial pressure of oxygen (P₀₂), being followed by first-order kinetics, and to the concentration of Fe(II)-edta by 0.7-order kinetics. Also, the difference in concentration of Fe(II)-edta between the inlet and the outlet of the column was found to be directly proportional to column-height (Z), being followed first-order kinetics and to be inversely proportional to the molar velocity of liquid (L_M) by 2/3-order kinetics. Thus, the oxidation rate of Fe(II)-edta is represented by the following equation :
The rate-determing step of oxidation is not ascribed to gas-film but to liquid-film or reac-tion itself.
The flue gas was allowed to contact with Fe-edta solution in terms of countercurrent method by using large scale sieve-cap shelf column on a large scale and the composition of liquid on each shelf was analyzed. As a result, NO_x was found to be absorbed in Fe(II)-edta at a top of the column and SO₂ in Fe (III) (OH)-edta at a bottom of it.

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Size distribution of maritime background aerosol was measured by use of an eight-staged Andersen impactor with a back-up filter. Sampling was made for 11 days on a cliff, 150 m above sea level, at one of Ogasawara Is. located ca.1000 km to the south of Tokyo. The weighed samples were analyzed by nondestructive neutron activation analysis for 25 elements under experimental conditions shown in Table 1. Neutron irradiation and cooling were conducted so as to reduce interfering activities by radionuclides, especially C1-38 and Na-24, for the measurement of short-lived nuclides. Table 2 shows mass concentrations of the size fractionated aerosol samples, and Table 3 shows the analytical results of the maritime aerosol samples for various elements. The continuous size distribution curves of the elements were drawn with reliable analytical data by numerical differentiation of the cumulative distribution curves. Aerosol concentration was very low, and its size distribution was unimodal with a peak at about 5 pm (Fig.1). These feature is quite different from those in urban aerosols whose size distribution is generally bimodal. Among the elements determined, the major components of sea salt, sodium and chlorine, showed a typical unimodal pattern with 5 pm peak (Fig.2 ( a )), and this fact enables us to conclude that sodium and chlorine could be generated from one common source and/or behave together. A number of cubic crystals of NaC1 were observed by scanning electron microscope in samples collected by a two-staged Lundgren impactor (Fig.5). A peak of "coarse" sea salt particles is thought to depend on arnvitational settling of larger particles while the particles are transported from sea surface to the cliff. Iron, scandium, cobalt and chromium that generated from terrestrial origins are unimodal characteristics with one peak of coarse particles. On the other hand, zinc, selenium and antimony that were more enriched than those in sea water and crustal materials (Fig.3), were mostly found in the "fine" particle range below 2 pm in aerodynamic diameter. This suggests that these elements might be transported from remote sources of industries or other anthropological activities.

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Electrophoretic mobilities of silica sols modified with a trace of alumina have been studied in the pH range from 2 to 7.5. The effects of alumina content and particle size of sols on mobility as well as the effects of concentration of silica sols and temperature dependence were also measured. The mobilities of those particles carrying negative charge are relatively high in aqueous solutions as compared with those of un-modified silica sols. This fact indicate the presence of strong adsorption of hydroxyl ions onto the surface of the particle. The modified silica sols were quite stable even in the acidic region.

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Measurement was made on the dielectric properties of Y-type zeolites in which the cations were exchanged with Li⁺, K⁺ and Cs⁺ to various degrees. In the LiHY samples, dielectric loss peaks (Fig. I-a) were observed in the same manner as NaHY which was reported previously.In the KHY and CsHY samples two loss peaks (Fig.1-b, 2) were found, and these peaks were classified into type- I and type- II, on the basis of the dependencies of the peak frequency on the degree of exchange. Type- I peaks, whose frequency changes with the degree of exchange, appear commonly in all samples exchanged with Li⁺, Na⁺, K⁺ and Cs⁺. Type- II peaks, whose frequency does not change with the degree of exchange, appear only in the samples exchanged with K⁺ and Cs⁺.

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The oxidation of propylene was studied at 350°C with alumina supported copper sulfate (catalyst-A) and copper phosphate containing a small amount of potassium (catalyst-B) as catalysts. When W/F was 5.0 g-cat. secimi, acrylaldehyde was formed by the partial oxidation of propylene on the catalyst-A, but no propylene oxide was obtained. However, when W/F was decreased to O.04 g-cat secfm/, propylene oxide was found to be produced together with CO₂, CO, acrylaldehyde, propionaldehyde and acetaldehyde.
The effect of operating conditions on propylene oxide formation was studied with the catalyst-B and the maximum selectivity of propylene oxide reached 25% under the following conditions (W/F=0.4 g-cat -secfm/, 350°C, propylene: 0₂: H₂0:N₂=78: 2: 8: 12). The effects of W/F on the reaction products indicated that propylene oxide was formed in the range of low W/F and that a part of acrylaldehyde produced was derived through the subsequent oxidation of the propylene oxide.

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The X-ray K-absorption spectra were applied to the state analyses of arsenic in its sulfide precipitates obtained in the process of the systematic qualitative analysis, and of selenium in the water extracts of alkali carbonate melts as well as in the solution of metallic selenium dissolved with hydrogen peroxide.
An X-ray diffractometer with a molybdenum-target tube was used. A large single crystal of topaz was set in the center of the goniometer as an analyzing crystal, and the sample was placed between a divergence slit and the single crystal. The precipitate sample was mixed with vaseline, coated uniformly on a piece of 6 p-Mylar film, and stuck on a -, filter frame without filter. A Mylar-window cell specially prepared was used for the liquid samples. The intensity of X-rays transmitted through the sample was measured at an interval of 0.01° in 20 over the range of about one degree around the absorption edge by the fixed time (40 sec) method. The product of the linear absorption coefficient p and thickness x of each sample was calculated by the use of the relation px=ln(I₀/I), where I is the intensity of X-rays transmitted through the sample, and I is the intensity measured without the sample. Each value of As was plotted against 2 0 to obtain the absorption spectrum of the sample, as shown in Fig.1 or 2.
The chemical state of each sample was determined by the comparison of the energy differences (Table 1 or 2) of the absorption edge, fine structure maxima, and minima from the K-absorption edge of each metal as follows. The precipitate described above, usually referred to as diarsenic pentasulfide, was revealed to be diarsenic trisulfide. Selenium was present as selenate ions in the solutions described above. The present method is easily applicable to the state analyses of amorphous precipitates and elements in solutions.

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Dimerization of 1-buten-3-one (MVK) in the presence of triphenylphosphine (TPP) has been studied.3-Methylene-2, 6-heptanedione was obtained in high yield in t-butyl alcohol at room temperature. The yield of was similary good in benzene or toluene (Tabe 1).1, 2- Bis(diphenylphosphino)ethane was also found to be effective as a catlyst for the dimerization of MVK.
The co-dimerization of MVK with other vinyl compounds such as acrylonitrile or ethyl acrylate promoted by TPP has also been examined.

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he compressibility of polymer solutions was measured at 30±0.015°C by the ultrasonic interferometer at MHz range, and the partial specific compressibility of the solute at infinite dilution (k₂₀) was determined.
Masuda et al. pointed out that k₂₀ in a good solvent depends on segmental density as shown in Fig.1, but this is not the case for the polymer solution near 0-state.
We proposed a new model for the compressibility of polymer solution composed of the hypothetical segmental liquid and solvent.
The experimental behavior of k₂₀ in this work was explained by the model.

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