Novel template effects of 1, 3-disubstituted 1, 1, 3, 3-tetraalkyldistannoxanes and their synthetic applications are summarized. The distannoxanes have a unique dimeric ladder structure induced by coordination of oxygen or hetroatoms to tins in the other chain. The bridging groups in the terminal positions are highly activated and thus easily substituted by an alkoxyl group. The tin atoms bonded to these electronegative groups are acidic enough to undergo coordination by one more carbonyl oxygen. Despite involving a metalloxane core, the distannoxanes are quite soluble in organic solvents. This is attributable to the doublelayered structure of the distannoxanes in which the surface alkyl groups prevent the inorganic core from being exposed to the solvent phase. These characteristic features lead to facile and selective chemical transformations of carbonyl compounds. Following to elucidation of the catalytic mechanism in urethane formation, distannoxane catalyzed transesterification is described wherein synthetiC usefulness and unusual solvent effect are revealed. The distannoxanes catalyze irreversible esterification reaction, the irreversibility arising from the doublelayered structure. Acetalization of carbonyls is also effected where unique transcarbonylation is involved. Finally, synthetically useful deacetalization and desilylation are described.

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The microwave spectra of ¹³C-species of cis, trans-ethyl nitrite were observed in the frequency range from 10 to 34 GHz. The following rotational constants for the ground state were determined;
A B C
¹³CH₈CH₂ONO 18018.90 ± 0.08 MHz 2931.14±0.01 MHz 2604.68±0.01 MHz
CH₃¹³CH₂ONO 17868.37±0.10 MHz 3008.28±0.01 MHz 2662.09±0.01 MHz
The rs value of C-C bond length of this isomer was calculated to be 1.517±0.004Å. The present C-C bond length is compared with the rs, (C-C) values reported for analogous molecules containing ethyl group, and the dependence of the C-C length on the electronegativity of the adjacent atom is discussed.

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Three kinds of non-crystalline alkali metal metatungstate hydrates, M₆H₂W₁₂O ₄₀. RH₂O (M=Li⁺, Na⁺, K⁺), with different water contents were synthesized by an ion-exchange method, in which a H⁺-type ion-exchange resin was used, and a rapid dehydration method. The water content of synthesized products was controlled with freeze drying. Those products were characterized with X-ray diffraction, IR spectroscopy, and thermal analysis, and the electrical conductivity and the transport number were measured. Although X-ray diffraction showed that those were all non-crystalline, the existence of metatungstate anions with Kegginstructure was confirmed by IR spectra. The electrical conductivity of the products depended on both the water content and the kind of alkali cation species. Their electrical conductivity was ca.10² times larger than that of crystalline ones. L The measurement of transport number indicated that the charge carrier was only protons. Thermal analysis showed that those products had no well-defined dehydration temperature in contrast to the crystalline alkali metal metatungstates. From these results, we concluded that non-crystalline alkali metal metatungstates had less restrained water molecules compared to crystalline ones, and were, therefore, good proton conductors.

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The fibrous-structured cheese, called "string cheese", is made from Mozzarella cheese curds by kneading and stretching it. At first, the stretching process was performed by each cheesemaker's individual skill. To mechanize this stretching and hardening process, the rheological properties of the curds such as Young's modulus, viscosity and relaxation time were determined in relation to the process. The results obtained were as follows. Since both Young's modulus (Fig.4) and viscosity (Fig.12) of the curds varied markedly with temperature, we assumed that temperature control is a very important factor in string cheese production. From the apparent viscosity and relaxation time, which were calculated from a rheological model consisting of only one Maxwell model (Figs.8, 9), it was suggested that the curds lost their fluidity and hardened at temperatures below 35°C. Consequently, the molding process of the curds should be finished above that temperature. Yield value of the curds was not observed at temperatures above 50°C and flow behavior was similar to Newtonian in the temperature range of 50 to 60°C (Fig.11). Poisson's ratio ( σ) of the curds was about 0.5, and shear modulus (G) and normal viscosity (λ) were calculated by using the following equations. G=E/2(1+σ), λ=(1+σ)Mechanization of Fibrous-Structured Cheese Production Process. I.

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An amorphous Au-Zr alloy was easily oxidized by treating in a wet atmosphere (H₂O/N₂; partial pressure of H₂O was 40 Pa) and changed into an active catalyst for hydrogenation of unsaturated compounds. The present catalyst system showed high selectivities in hydrogenation of unsaturated carbonyl compounds, especially 2-butenal to 2-butenol. Furthermore, the present catalyst system showed high selectivities (more than 99%) for hydrogenation of unsaturated hydrocarbons, i. e.1, 3-butadiene, propadiene, propyne and 2-methyl-1, 3-butadiene to monoenes. Hydrogenation rate of 1, 3-butadiene was a hundred times faster than that of 1-butene at the same reaction condition. These results show that the present catalyst system has unique active sites in the hydrogenation,
The present catalyst system contained almost no impurities except for 80 ppm of Fe. No condensation of metals was observed on the surface of an oxidized alloy using XPS. We consider that active sites in the present catalyst system are not the sites formed by impurities but by a part of gold which was highly dispersed.

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ZSM-5 type zeolites containing alkaline earth metal, especially calcium, showed the best catalyst performance for methanol conversion to light olefins at high temperatures above 500°C. In order to extend the catalyst life, the control of the zeolite crystal size was studied. First we investigated the effect of the amounts of aluminium and calcium in the synthesis mixture on the zeolite crystal size. It was found that the crystal size became small with an increase in these amounts. However, we could not obtain the zeolites with Ca/Al₂ ratio of more than 3, which were effective for methanol conversion to light olefins under high temperatures. Then, we tried to control the crystal size of the zeolites containing calcium by adding boric acid. It was found that the zeolite crystal size became small with the amount of boric acid and in the case of SiO₂/B₂O₈ ratio of 20 in the synthesis mixture, the crystal size of the zeolite with Ca/Al2 ratio of 3.29 was below 1 μm (Fig.2, Table 1). Fig.4 shows the results of methanol conversion over the micro-crystalline zeolite with high Ca/Al₂ ratio under the reaction conditions of LHSV=.4h^-1 and 600°C. The initial activity of the zeolite synthesized in the presence of boric acid was similar to that of the zeolite synthesized in its absence. The catalyst life, the time with a selectivity for ethylene and propylene of >50%, of the zeolite prepared in the presence of boric acid was approximately 30 h, which was 1.6 times that of the zeolite prepared without the acid.

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The effect of removal of chloride ion was investigated over Pd/MgO catalysts prepared by the various pretreatment. The residual chloride ion from the catalyst precursor compounds (PdC1₂) depressed the surface area (57 m². g-cat^-1) of MgO-support, as well as Pd dispersion (0.35-0.38) and catalytic activity (40-50 mol% of total conversion) (Table 1). It was suggested that the chloride anion played a role as a promoter in transforming MgO into Mg (OH)₂. This transformation was promoted by boiling the sample with deionized water. T he chloride-free powder sample was obtained by washing the precipitate after the transformation process. Pre-calcination process at 600°C gave the stable Pd0 in which the effluence of Pd₂+ion decreased. Subsequently, dehydration of the chloride-free Mg(OH)₂ at 600°C gave high surface area powders (100-170 m². g-cat^-1) (Table 1). The Pd/MgO catalyst prepared by the procedure (Fig.1), consisting of impregnation with PdC1₂ or Pd(N0₃)₂ over MgO or Mg (OH)₂, pre-calcination (600°C), boiling with water, removal process of chloride, and th en calcination (600°C), revealed higher values in surface area (more than 100 m². g-cat^-1), Pd dispersion (0.6-0.9), Pd content (0.7-0.9 wt%) and catalytic activity (more than 90 mol%with 100 mol% selectivity) in a methanol decomposition (Table 1). The remarkable degrees of Pd dispersion were observed on these Pd/MgO catalysts calcined at 400--700°C, and the highly active catalysts were also obtained by the calcination (500-600°C) and the reduction (400, 600°C).

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Liquid phase oxidation of 2, 6-dialkylphenols with molecular oxygen was studied using basic metal oxide catalysts containing various metal ion. The basic metal oxides employed in this study were MgO, CaO, La₂O₃, ZrO₂, and ZnO, and the additive metal ions were Mn^II, Co^II, Fe^II, and Cu^II. The basic oxide were completely inactive for the reacti on, while these oxides containing the metal ions were found to show characteristic activities. The oxidative coupling reaction of 2, 67di-t-butylphenol (DBP) took place readily over Mnn ion-containing MgO catalyst to form diphenoquinone (DPQ) selectively. At an optimum condition. DPQ was yielded in 98% with almost 100% selectivity. Over Co^II i on-con taining.1 1La₂O₃ catalyst, DBP was also converted into DPQ but the selectivity was slightly low because of the formation of a small amount of benzoquinone (BQ). Fe^III and Cu^II ion were ineffective additives for the reaction. It was revealed that benzene was the most effective solvent for the formation of quinones, while the yield of quinones was decreased when polar and protic solvents such as methanol or acetonitrile were used. The Mn^II ion-containing MgO catalyst also showed activity for the oxidation of 2, 6-dimethylphenol but mainly catalyzed C-O coupling reaction to form polyphenyleneoxide. Cl-substituted or non-substituted phenol was not oxidized by use of the present catalysts. It was suggested that the surface base property of the catalyst and the state of the added metal ion on the surface strQngly affect the catalytic activity and selectivity for the oxidation of phenols.

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The electronic absorption spectra of di-2-pyridylethanedione (2, 2'-pyridil) have been measured in EPA at room temperature and 101 K, and compared with those of benzil. The polarized absorption spectra of 2, 2'-pyridil and 2-acetylpyridine have been measured in the stretched PVA film at 101 K, the latter molecule having a half π-electron framework of the former. It is found that, for instance, the weak band system of 2, 2'-pyridil in the wavelength region 320-430 nm consists of two electronic transitions, whose 0-0 bands are at 398 nm and 352.0 nm. Both electronic bands are assigned as the transitions from the n-orbitals of the oxygen atoms to the π*-orbitals. The comparison between the observed and calculated splitting values of the two n--π* transition energies indicates that the 2, 2'-pyridil molecule is twisted around the central C-C bond by about 80° in solution. From the configuration analysis, it is found that the 398 nm band is due to the transition from the n-orbitals of the oxygen atom to the π*-orbitals in the 2-acetylpyridine skeleton to which the oxygen atom belongs, and the 352.0 nm band to the transition from the n-orbitals of oxygen atoms to the π*-orbital in which the n- and π*-orbitals belong to the different 2-acetylpyridine skeleton s.

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Hydroxymethylation of melamine with formaldehyde (F) was kinetically investigated in aqueous N-(2-cyanoethyl)morpholine (B) and the conjugate acid (HB⁺) buffers at pH 4.9([HB⁺]/[B]=2.0)--pH 5.9 ([HB⁺]/[B ]=0.2) at 40--62°C. The second-order rate constant k shown by initial rate R₀=k[MH_f][F] was given by k - k' = k_HB+[HB⁺]+ k₈[B]; here, MHf and k' are the free base of melamine and the rate constant in unbuffered media, respectively. Activation parameters (frequency factor and activation energy) were calculated by the use of Arrhenius plots for acid-catalyzed reaction (the first term of the kinetic equation) and basecatalyzed reaction (the second term). Acid-catalyzed reaction mechanism was discussed on the basis of the frequency factor thus obtained as well as that of Bronsted plots (slope, 0.35), and consequently rate-determining step was proposed to be N-C bond formation by the addition reaction of melamine with formaldehyde (the formation of the zwitterionic intermediate, T-, HB⁺). Studied on Formaldehyde Resin. XXXIII.

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An electroless plating technique was applied to preparation of supported thin palladium films permeable only to hydrogen. Before electroless plating, palladium nuclei were deposited on the outer surface of a porous tube by two step immersion procedure consisting of sensitization and activation treatments with tin(II) chloride and palladium(II) chloride solutions, respectively. The rate of palladium deposition in electroless plating was related to theconcentration of palladium nuclei, which increased with repeated number of the treatments. Palladium deposition was retarded by the presence of tin, which was deposited during the treatments. The treatment with a silver nitrate solution before the activation treatment promoted the formation of palladium nuclei. Electroless plating of palladium was carried out by use of an alkaline solution containing tetraammine palladium complex, EDTA, aqueous ammonia and hydrazine. The rate of plating was influenced by the bath temperature and the concentration of hydrazine. Under the conditions studied, palladium was plated on the porous glass tube by two times faster than the conventional plating method so far reported.

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Four noncyclic diamide compounds (L1, L2, L3, L4) were prepared and extraction and liquid membrane transport measurement were examined for some transition metal ions (Cu²⁺, Ni²⁺, Co²⁺, Zn²⁺). In the presence of the lipohilic anions such as picrate or C1O4^- ions, Cu²⁺ was preferentially extracted and transported by L2 and L4, but Ni²⁺, Co²⁺ and Zn²⁺ were not transported by these ligands. More than 90% of Cu²⁺ was transported by L4. at the equilibrium state. It is noted that active transport of Cu²⁺ was observed for L4. in the absence of the lipohilic anion, but not for L2 under the same experimental conditions. Further a considerable decrease of pH was observed by adding CuCl₂ to the solution contaning L4, but not for L2, L1 and L3. These results suggested that two amide-proton of L4 dissociate upon complex ation even in weak acidic medium and those of L2 do not. Concequently, the deprotonated L4-dianion can form neutral Cu-complex which can pass through liquid membra ne without any accompanying anion. The extractability and the transport rate of Cu²⁺ rapidly decreased below pH=3.

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The photochemical decomposition behaviour of hexacyanoferrateOlnion ([Fe(CN)₆]^3-) in alkaline solution was studied using an ultraviolet light source (low pressure mercuty lamp)in nitrogen atmosphere by means of UV spectra and chemical analyses. The overall photochemical reaction of [Fe(CN)₆]^3- was foun d to cause some complicated processes depending on the concentration of hydroxide ion (OH^-). In 0.1 mol.dm^-3 NaOH solution, [Fe(CN)₆]^3- was first co nverted to aquapentacyanoferrate (II) ion ([Fe(CN)₅.H₂O]^3-) and cyanide ion (CN^-) under the irradiati on. Under further irradiation, iron(II) ion (Fe(II)) produced in the photo-induced decomposition of [Fe(CN)₅H₂O]^3- gave rise to the precipitate of Fe(III) hydroxide and free cyanide ion was oxidized to cyanate ion (OCN^-). OCN^- and Fe(III) hydroxide may be formed by the reaction of CN^- and Fe(II) with the oxygen generated in the following photo-reaction of OH^-.2 OH^- --1/2O₂ + H₂O + 2 eIt is assumed that the electron (e^-) is used to reduce the Fe(III) of [Fe(CN)₆]^3- to the Fe(II) of [Fe(CN)₅. H₂O]^3-. Furthermo re, effects of several semiconductor powders on the decomposition reaction of [Fe(CN)₆]^3- were also examined.

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The concentrations of trace elements (Sn, Cu, Zn and Mn) in muscle and organs of the cultured yellowtail were determined by means of atomic absorption spectrophotometry after wet ashing with mixture of nitric acid and hydrogen peroxide, and the sampling methods of muscle segment for the determination of trace elements were studied. From these studies, following results were obtained. The concentrations of copper in yellowtail were liver> blood > kidney, intestine > spleen, stomach > p yrolus, muscle, ovary, zinc were o vary > kidney > spleen > liver, stomach > pylorus, intestine, blood > muscle, manganese were liver > in testine > kidney >stomach, spleen, pylorus > b lood > muscle, ovary, and those of tin in every organs were lower than 1.0 μg/g. On the other hand, the concentrations of copper in red muscle were higher than white muscle. Thus, the concentrations of copper in muscle segment were gradually increased from head to tail of the cultured yellowtail. Studies on the Behavior of Some Trace Elements in Bay Area. IV.

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The concentration ratio between Rb and Sr in soils varies in different localities. The ratio has been used to presume an earthenware-producing district in an archaeological field. In this study, desert soils in Taklamakan, Gobi and Alashan, these deserts were considered to be a major source of Kosa, and soils in Japan were Analyzed by X-ray fluorescence method. The ratios of Rb/Sr in desert soils in China were about 0.47, and those in Japanese soils were more than 0.80 in the western Japan and less than 0.60 in the eastern Japan. These ratios in soils showed clearly different localities. Aerosol samples monthly collected at 11sites in NASN (National Air Surveillance Network), 1981, were also analyzed by X-ray fluorescence method. The ratio of Rb/Sr in aerosols was 0.60 in the western Japan and 0.40in the eastern Japan in the average of 12 months. On the other hand, the ratio of Rb/Sr in aerosols in metropolitan and industrial area such as Tokyo, Nagoya and Osaka was 0.90; higher than other area due to the contribution of Rb from the steel industry.
As the result of measurements of Rb and Sr in both aerosols and s oils, it was found that the ratio of Rb/Sr in aerosols at each site in Japan strongly reflected that in soils except at metropolitan and industrial sites. However, the ratios of Rb/Sr in aerosols at most of sites were close to those of desert soils in China (0.47), on May, 1981 when Kosa phenomenon was observed everywhere in Japan. Especially, in the western Japan, the ratio of Rb/Sr in aerosols largely decreased and became close to 0.47 on May, 1981. This is because the western Japan is geographically near the Asiatic Continent and aerosols in the western Japan were strongly affected by desert soil particles transported by Kosa phenomenon.

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Reactions of 2-cyano-4-(m-methoxypheny1)-3-methy1-2-butenenitrile (2) and ethyl 2cyano-4-(m-methoxypheny1)-3-methyl-2-butenoate (3) with concentrated sulfuric acid afforded 2, 3, 6-trisubstituted 1-naphthylamines ( 4 ) and (5 ), respectively. Reaction of (3)with acetamide afforded 2, 3, 8- and 2, 3, 6-trisubstituted 1-naphthols, (6 ) and ( 7). Compounds, (8 ) and ( 9 ) obtained by methylation of (6 ) and (7), reacted with methylmagnesium iodide to give 2-acetyl-1-naphthols, (1O) and (1 1), which were analogous to musizin (2acetyl-3-methy1-1, 8-naphthalenediol).

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p-Propylphenol was coverted to p-methoxyphenylpropane and then oxidized with lead tetraacetate in acetic acid to give anethole. The synthetic route may be general for a-acetoxylation of the side chain of alkylphenol derivatives. Intermediate α-acetoxylated compounds were also isolated and their 'H- and ¹³C-NMR spectra were presented together with those for final products.

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Yamaguchi University; Tokiwadai, Ube-shi 7 5 5 Japan The reaction of acetanilides with equimolar amounts of benzyltrimethylammonium tribromide and zinc chloride in acetic acid under mild conditions gave the bromo-substit-4-ted acetanilides in good yields. Halogenation Using Quaternary Ammonium Polyhalides, XXV.

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