The mechanical mixtures of Co-Ni/MnO-ZrO₂ and zeolite were used as catalysts for the selective synthesis of gasoline by CO hydrogenation. Formation of branched-paraffins was promoted but that of higher hydrocarbons than carbon number of 10 was suppressed by combination with zeolite. The product distribution strongly depended on the type of zeolite catalyst. Pentasil zeolite was active for the formation of branched-paraffins, probably because of the cracking reaction occurring on the strong acid sites. The formation of branchedparaffins was further promoted by ion-exhange with Pt. The mixture of Co-Ni/MnO-ZrO₂and PtH-pentasil zeolite was very active for the formation of gasoline with high octane number.

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It is well-known that clay minerals can be used as acid catalysts for organic reactions. Metal cations held in the interval. spaces of clay minerals have been reported to act as Lewis acids. There are other acidic sites at the broken edges of crystals in clay minerals. How ever, the catalytic activities of these sites have not been studied so far. From this viewpoint, catalytic activity of some unmodified clay minerals have been examined here by means of dehydration, dimerization, and cyclization of 2-phenyl-2-propanol. Clay minerals examined are as follows montmorillonite, acid-treated montmorillonite (Japanese acid Clay), halloysite (tubular, spherical), kaolinite, and amorphous silica-alumina. On montmorillonite, the reactions did not proceed at all, but proc e eded rather smioothly on other five clay minerals investigated. The activity of the clay minerals was been estimated from the rate constants of these reactions. The change in the basal space of the clay minerals did not affect the 'catalytic activity, and the reaction rates did not depetd on the surface area of clay minerals. Phosphoric acid adgOrbed on clay surfaces suppressed the dehydration reaction in the series of reactions. From these results, it is suggested that the catalytically active sites of clay minerals are present at the broken edge of crystals.

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The dehydration of the various particle size of calcium sulfate dihydrate (CaSO₄.2H₂O)has been studied under various nitrogen pressure up to 7 MPa by using high-pressure differential thermal analysis (HPDTA). The intermediate products formed at desired temperatures on HPDTA were identified by X-ray diffractometry and by differential thermal analysis thermogravimetry and/or by differential scanning calorimetory in the self-generated atmosphere and were oberved also by scanning electron microscopy. The sh arp endothermic peak appearing at 120-150°C shifted to higher temperature with an increase in particle size, and the temperatures of the peak was directly proportional to logarithms of the particle size, which was caused by the release of 3/2 water of crystallization and by the transformation to α-hemihydrate (peak A 1). Uner 1 MPa of nitrogen pressure, the large particle dihydrate was rearranged into anhydrate II via a-hemihydrate, while the small particle dihydrate produced α-hemihydrate and β*-hemihydrate. The DSC peak temperature of the latter was lower than that of typical *p-hemihydrate obtained by the dehydration of dihydrate in atmosphere. The SEM micrograph of t he products indicated that the surface of crystals were smooth different from that of the typical β-hemihydrate. It was thought that β*-h emihydrate was an intermediate leading to a-hemihydrate or fine crystals of α-hemihydrate. It was recognized that the rates of the dehydration of dihydrate, the disolution of dihydrate and hemihydrate into the released water, the crystallization of a-hemihydrate were influenced by the particle size of starting material, dihydrate. *

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Ozone production under irradiation of a conventional low-pressure mercury vapor quartz lamp (main spectral line: 253.7 nm, 8 W, cylinder type) was measured for the air containing oxygen, carbon dioxide and ozone in order to estimate the ability of the lamp for ozone production.
The concentration of ozone produced increased at first then decreased with decreasing gas flow rate, and decreased with increasing concentration of carbon dioxide. Moreover, the production of ozone was enhanced in the air containing a small amount of ozone, but it began to decrease when the ozone concentration increased beyond over 52 ppm.
The produced ozone concentration increased with gas flow rate in the range of low flow rate. However, it became to decrease in the range of high gas flow rate. That is, a reversing zone of concentration was always found. The reversing zone shifted toward the ran ge of higher gas flow rate as the concentration of oxygen, carbon dioxide and ozone increased. Formation and Decomposition of Ozone by Ultraviolet Ray. I.

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A method for preparing crystalline titanium(IV) bis (hydrogenphosphate) monohydrate, Ti(HPO4)². H²O (α-TiP), was established by the raction of titanium( IV) hydro xide, TiO²nH²O, or titanium(IV) oxide, TiO² (rutile and anatase type), with orthophosphoric acid in an autoclave. In the titanium ( IV) hydroxide and titanium(IV) oxide systems, the preparation of α-TiP was strongly dependent on mixing ratio (P²O⁵/TiO²), heating temperature, and heating time. The recommended method for the prearation of α-TIP is mixing ratio P²O⁵/TiO²=1.2-1.5, heating temperature 200'-225°C, and heating time 5 h. α-TiP prepared by the present method is not soluble in distilled water and hydrochloric acid (0.1 mol dm^-3), but slightly dissolves in sodium hydroxide and ammonia solutions. α-TiP effectively adsorbed ammonia in an aqueous solution and ammonia gas.

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Cation exchange with Mn²⁺, Fe⁺², Co⁺² and Ni²⁺ was carried out for synthetic swelling sodium-flourine micas having variable layer charges [Na_xMg_3-xLi_x(Si₄O₁₀)F₂, x =1.00, 0.76, 0.61, 0.42] and swelling-dehydration characteristics of M²⁺-exchanged micas were investiga ted. The swelling characteristics of exchanged micas depend mainly on interlayer M²⁺ cations and slightly on layer charge. According to the observed basal spacings (d₀₀₁) the stable phase of M²⁺-exchanged micas in air (temp=20°C, R. H. =60%) was two-layer hydrated type (d₀₀₁≈14.6 Å), while that in water was three-layer hydrated type (d₀₀₁≈18.4 A). The b asal spacings of the two-layer hydrated type of M2^+-exchanged micas decreased in three steps with increasing temperature, and thee endothermic peaks appeared on DTA curves, indicating the dehydration of the micas. At the highest one of the endothermic peak temperatures (Th) dehydration of one-layer hydrated micas occurred. Then the temperature of Th was regarded as a parameter representing dehydration tendency of interlayer water molecules. In the case of the micas having the same layer charge, the temperature of Th increased in the order Mn2^+- <Fe²⁺ -<CCo2^+- <Ni²⁺- exchanged mica, and this order is the same as that of hydration energy of M2+. For M²⁺- exchanged micas having the same species of interlayer cation, the Th increased with decreasing layer charge. These facts suggest that the dehydration characteristics of M²⁺-exchanged micas can be explained in terms of the nature of M²⁺cations and the effects of layer charge on the bond between M2+ and H₂O.

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A lead zirconate titanate (PZT) was prepared by following methods: 1) Solid-solid reaction between TiO₂, ZrO₂ and PbO (DRY method), 2) solid-solid reaction between PbO and a mixed oxide prepared by a freeze drying of a mixed solution of titanium nitrate and zirconium nitrate (COMBINATION method), 3) freeze drying of a mixed solution of titanium nitrate, zirconium nitrate and lead nitrate (FULL method),
By the DRY method, PbTiO₃ was formed as an internicdiatc product and a single phase PZT was obtained by a firing at 110°C. By the COMBINATION method, the single phase PZT was obtained by a firing at 90°C without the formation of the intermediate prod uct.By the FULL method, the single phase PZT was obtained by a firing at 580°C without the formation of the intermediate product. A compositional fluctuation of PZT prepared by the COMBINATION method and that by the FULL method were not detected by X-ray diffra ction analysis, The sinterability of PZT prepared by the COMBINATION method and that by the FULL method were higher than that by the DRY method. The permittivity peak of PZT prepared by the COMBINATION method and that by the FULL method at the Curie temperature were about twice as large as that by the DRY method.

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On adding thiocyanate in excess to an aqueous solution of cobalt(II), one or possibly two NCS^- ligands are coordinated and the light red color of the solution is deepened somewha t. However, with the addition of a small amount of Triton X-100, a nonionic surfactant, to the mixture caused it to take on a deep blue color, indicating a complex coordinated with four NCS^- ligands to possibly be formed. At a slightly higher concentration of cobalt(II), a deep blue tarry gel was deposited. This gel whose composition remained essentially constant on treatment with various amounts of potassium thiocyanate and Triton, was a stoichiometric adduct such as K₂[Co(NCS)₄]2 Triton. The recovery of cobalt(II) remaining in the supernatant was minimized when the addition was conducted at a molar ratio of Triton/Co (II)=2. When Triton was insufficient to give this ratio, it precipitated completely and the supernatant took on a light pinkish color at higher Trition concentration, precipitation of the "blue gel" decreased and the supernatant showed a deeper blue color. The structure of the adduct in the "blue gel" was concluded to be such that [Co(NCS)₄]^2- is surrounded and protected by hydrophobic groups of two molecules of Trition; each potassium ion is cover ed by a hydrophilic poly(oxyethylene) chain of Triton so that the electric charge of the complex is neutralized.

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Some dicinnamates containing quaternary ammonium salt were synthesized by the quaternization of N-methylbis[2-(cinnamoyloxy)ethyl]amine with various alkyl bromides. The photochemical behavior of the obtained compounds was evaluated in water or some organic solvents. The rate of photochemical reaction of the dicinnamates obeyed second order kinetics on the initial stage, and it was found that the reaction proceeded quantitatively by the photo-irradiation for long time. The photochemical reactivity was also strongly affected by the kind of reaction media. That is, the rate of bis[2-(cinnamoyloxy)ethyl]dimethylammonium bromide (3 a) in water was about three times higher than that of 3 a in methanol, and the rate in dichloromethane was two times higher than that in methanol. However, the rate of 3 a was not affected by the kind of substituent on the ammonium salt. Furthermore, it was found that the dicinnamates containing quaternary ammonium salt have higher photochemical reactivity than the corresponding hydrophobic compound 1, 5-pentanediol dicinnamate. The photochemical reversion of, the resulting photoproduct was also studied in water. As a result, although the photodimerization was proceeded quantitatively by irradiation with 313 nm light, the extent of photoreverse reaction by irradiation with 254 nm light was about 20%.

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The present work is the fundamental research of metal phthalocyanine (M-PC) as catalyst for hydrocracking of Khafji asphaltene. Co-PC, cobalt tetrapyridopor phyrazine (Co-TPP, in which 4 benzene rings are replaced by pyridine rings) and cobalt dibenzodipyridoporphyrazine (Co-2 P, in which 2 benzene rings are replaced by pyridine rings) were used as M-PC catalysts (Fig.1). The reaction products are liquid product, BS-HS, BS-HI, BI-TS and BI-TI fractions. In the reaction with Co-TPP catalyst, liquid product is produced only 0.9% at 300 min period, while the formation of BS-HS fraction usually developed to about 30%. Yield of BI-TS and BI-TI fractions are larger than that with Co-PC (Figs.2, --4).
In. the reactian with Co-2P catalyst, the liquid product was not observed until 120min. The liquid praduci was sirnilar to thecaseof Co-PCat240min. On the other hand, BI- TS fraction was twice as much as that with Co-PC catalyst(Fig.5).From thesef ractional distributions and thestru.ctur alanaly sesofreaction products, Co-2P catalyst has an effect similar to Co-PC While Co-TPP was faund not to ha ve the catalytic activity(Table3). ItwasrecognizedthatPCtypecatalystsworkasahydrogenationcatalystexceptCo-TPP (Fig.6). We think the hydrogen holding of PC type compounds is attributable to the following. In the Co-PC molecule, reduction can take place at the 16 peripheral carbon atoms of the four fused benzene rings. Reduction of Co-TPP occurs at only 4 nitrogen atoms of four fused pyridine rings. Co-2 P has the characteristics of Co-PC and Co-TPP combined. The catalytic activity of PC type compunds depend on the difference of hydrogen holding except Co-TPP, namely their reduction ability.

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Amino polycyclic aromatic hydrocarbons (APAH) and polycyclic aromatic nitrogen heterocycles (PANH) in coal-derived oil (bp 150--400°C) were analyzed in detail. The coal-derived oil was distilled into four fractions. Basic compounds were extracted with acid and APAH was converted into trifluoro acetylamino derivative (TFA-APAH). Subsequent acid extraction enabled the complete separation of insoluble TFA-APAH and soluble PANH (Fig.1). They were analyzed qualitatively by a new technique combining the information obtained, from capillary GC-MS, retention index (RI) for capillary GC and HPLC-fluorescence spectroscopy, and analyzed quantitatively by mass chromatography (MC).
The components of PANH increased in the order of C₀-C₈ substituted quinoline (23.90% in the basic fraction) >C₀---C₇ substituted. benzoquinolined-phena. nthridine (13.71%) >C₀--C₇ substituted Azapyrene (11.28%)>C₀--C₇ substituted phenylpyridine (10.75%)>C₀--C₇ substituted phenylquinoline (5.35%) (Table 6). The componsnts of APAH incr eased in the order of C₀-C₈ substituted aniline (5.00% in the basic fraction) >C₀-C₆ substituted aminoindan (4.17%) >C₀--C₆, substituted aminobiphenyl (1.94%) >C₀--C₈ substituted aminonaphthalene (1.30%) >C₀--O₅ substituted amino phenanthrene (1.06%) >C₀--C₅, substituted aminofluorene (0.79%) (Table 7). Carcinogenic PANH was constituted 33.4 % and carcinogeni c APAH was constituted 5.3%of the basic fraction, respectively. Carcinogenic components of them are described (Table 6 and 7).

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For the second-order optical nonlinearity, the organic molecule has to crystallize in the lack of inversion center. We have statistically studied the designing of molecules which form easily noncentrosymmetric structure and make effective orientation for bulk phase matching. Our MO calculation by MOPAC AM 1 method demonstrated that the conformation of methanediamines, in which two aniline derivatives are bonded together with methylene bridge (-CH₂-), fold down and two aromatic rings are twisted. We call them as Λ type conformation. A Λ type molecule seems to crystallize into noncentrosymmetry because it easily stacks along same direction. The intramolecular char ge transfer contribution to the nonlinear polarizabilities of methanediamines has almost a two-dimensional character, therefore the largest molecular hyperpolarizability tensor β_ijk, i, is a non-diagonal component, for example β_yxx calculated by Finite-Field method. All methanediamines synthesized in our laboratory are SHG active as studied by the powder method. From the analysis of the crystal structure determined by X-ray method, we found that the molecule forms a Λ type conformation and crystallize in the noncentrosymmetric space group. In the crystal unit cell, Λ type molecules stack along one direction, which means all the molecular dipoles align along the crystal axis. This is close to a optimum orientation which two aniline analogues can attain in order to maximize the crystal phasematched nonlinearity, as reported by Zyss et al. As a consequence, the largest β tensor effectively contributes to the phase-matchable nonlinear optical coefficient calculated according to the oriented gas-model.

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Rhodamine 6 G used for spectroscopic dye laser is decolored by the irradiation of visible light, and the output power of dye laser becomes lower. For improving this problem, the substances which form its molecular complexes were added and their effect of them on the photobleaching rate of Rhodamin 6 G was studied. Positive effect was observed by addition of β-cyclodextrin, γ-cyclodextrin and sodium deoxycholate. Addition effect of caffein and thiourea were small and of α-cyclodextrin was negligible α-cyclodextrin with 4.5 Å hole diameter cannot include the active site for singlet oxygen, of Rhodamine 6 G which is as large as 7 Å. On the other hand, γ-cyclodextrin with 8.5 Å hole diameter allows penetration of the singlet oxygen. Fluorescent intensity of Rhodamine 6 G in aqueous solution decreased a little by addition of β-cyclodextrin, γ-cyclodextrin, sodium deoxychoate and caffein, and it was not affected by addition of α-cyclodextrin. But it largely decreased by addition of thiourea and guanosine-5'-monophosphate.

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A coprecipitation method with silver bromide was studied for fluorescent X-ray spectrometry of trace amount of chloride ion in natural water. Twenty nil of 50 w/v% ammonium nitrate was added to 500 ml of sample water, followed by adding 10 ml of 0.2gBr/l potassium bromide solution and 10 ml of 5.0gAg/l silver nitrate solution. Chloride ion was quantitatively precipitated. The precipitate was collected onto a membrane filter and the fluorescent X-ray intensity of chloride was measured. The linear range of calibration curve was from 0.1 to 1.0 mg/l, the detection limit for chloride ion was 0.04 mg, and the lower limit of determination was 0.14 mg. This method was not influenced by sample water from 100 to 1500 ml, an d was satisfactorily applied to determination of chloride ion in natural water.

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It was studied to use a ceramic membrane, which is known to be efficient for the separation of compounds having varoius molecular weight, for the purpose of separation of amylose from starch. A tube of ceramic membrane (5 mm in outside diameter, 50 cm long, 74.5cm2 of surface, 0.05 tm in average dimeter of hole), which is loaded into a metal tube (7.5 mm in inside diameter), was used for the separation with connecting a pump an d a feed tank filled by 2 dm3 of 1% corn starch suspension. As a result of surveying the optimum condition for the separation of amylose, the lower pressure, the higher feed velocity and the higher temperature were found to bring out the higher concentration of amylose in the filtrate through the ceramic membrne. The working of separation was carried out during 24 h with a condition of 3.0 m/s feed velocity at 0.3 kg/cm2 of gauge pressure and 60°C. The solid material was obtained by freeze drying after evaporating the filtrate to reduce the volume by 1/10. The yield was 3.0 g from 22 g of corn starch.

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Although eggshell is partially covered by collagen film, it is sufficiently porous to adsorb a considerable amount of formic acid gas (72 cm3/g) in contrast to calcium carbonate reagent. A high temperature treatment at 700°C removed completely the collagen film, and decomposed the eggshell to calcium oxide which showed the same adsorptive property as that of the high temperature treated reagent. The eggshell can be used as the economical basic adsorbent with or without heat treatment at higher temperatures,

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