Host-guest type interactions based on multipoint hydrogen bonding in apolar organic media were investigated. Porphyrin derivatives having 2-hydroxy-1-naphthyl groups and cyclic tetrakis(resorcinol) served as hosts; these have hydrogen-bonding sites composed of hydroxyl groups. Guests studied here include such biorelevant molecules as amino acids, quinones, dicarboxylic acids, diols, sugars, and nucleotides. “Intramolecular” hydrogen bonds in a multipoint host-guest interaction bring about not only a sizable selectivity for the best-bound guests but also remarkable chain length and stereoselectivities. It is generally noted that an “intramolecular” hydrogen bond is more favorable than the corresponding intramolecular hydrogen bond by a factor of approximately 1.5 kcal/mol. Sugars can be solublized in apolar organic media via such multiple hydrogen bonding interactions, where solubilized sugars show a remarkable selectivity as for the anomeric stereochemistry. The extractabilities of various sugars, on the other hand, are governed by the lipophilicities of the sugar molecules as a whole. Various applications of multipoint hydrogen bonding were also attempted. Most importantly, the host-guest interaction based on noncovalent forces can be utilized for the construction of functional molecular assemblies as well as for the determination of stereochemistry of chiral guests. Application to the development of a new synthetic chemistry of sugars and new multifunctional catalytic systems are also described.

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Alumina- or zirconia-pillared clay with different pi llar distributions was prepared by exchanging (Na/Ni)-montmorillonite, the cation-exchange capacity (CEC) of which had previously been varied, in a solution containing the respective pillar precursor. While the interlayer distance of the pillared clay remained almost unchanged, the amount of alumina or zirconia incorporated in the clay as pillars increased with increasing CEC of the starting montmorillonite. This leads us to conclude that the pillars were distributed in the interlayer space more closely and as a result the lateral distance between pillars was smaller for the clay with larger amount of pillars. The structure and the valency of precursor cations different from each other suggested that the lateral distance of zirconia-pillared clay varied in the range smaller than that for alumina-pillared clay. The catalytic property of the pillared clay with d ifferent pillar distributions was studied for toluene alkylation with methanol and for rn-xylene conversion. In toluene alkylation, xylene (about 80%) and trimethylbenzene (about 20%) were produced as main products on all pillared clays. A considerable decrease in the catalytic activity was also observed with time on stream. The activity decrease was more pronounced on the alumina-pillared clay with larger lateral distance between pillars, although such a clay exhibited lower initial activity. For zirconia-pillared clay, on the other hand, no systematic variation was observed 1058 1991 No.8in the extent of activity decrease, even though the lateral distance was different from one another. In m-xylene conversion, both isomerization and disproportionation occurred on alumina-pillared clay, while only isomerization with negligible disproportionation occurred on zirconia-pillared clay. The catalytic activity increased for both reaction with increasing amount of alumina pillars but isomerization was enhanced much more than disproportionation. The variations of the catalytic porperty with the pillar distribution and also with the kind of pillar were discussed in terms of the relative dimension of coke or of the reaction intermediate with the pore size of the pillared clay.

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The rheological properties of fibrous-structured cheese and their effects on the “stringiness” were studied. And the equations which showed the relationship between the thickness of stringy materials and the rheological properties were proposed. Two samples were prepared: one sample was cut off parallel to the stretching direction of the fibrous-structured cheese (parallel sample), and the other was cut off at a right angle (cross sample). Shear strength (Fig.3) and dynamic modulus (Fig.4) of these samples showed the anisotropy in the rheological properties.The diagrams in Fig.11 show the stringy material observed when the fibrous-structured cheese was torn. Samples were placed parallel to the X-axis, and torn at the tearing angle a of 90° by pulling the end parallel to the Y-axis. Then stringy material with the angle 0 was observed. In many cases, the angle θstayed constant during the tearing process, assuming this constant angleθ corresponded to the balance of the tensile force and tearing force. Let l be the length of sample torn, l_o the original length and l_s the total length of stretched stringy material. Then the strain r is given by the following equation (refer Fig.11 b). r= (l_s -l_o)l_o= {secθ/(1tan θ) }-1 1Furthermore, let A be the sectional area of the original stringy material, E the Young's modulus, B the breaking strength, and P the tear stength. Then the tensile force is given by ATE, the breaking force is given by AB and the tearing force is given by A^1/2P. In many cases, the shape of the cross section of the stringy material maybe approximated as a square. Therefore, it is convenient to regard A as a square of thickness of the stringy materials. A" was used as the effective length in the calculation of the tearing force. As the tensile force is equal to the tearing force, ArE= A1/2 p and r<r <B where, TB is the breaking strain obtained from the tension test. Thus, the angle θ or the thickness of the stringy mater ials were calculated using four rheological parameters, Young's modulus, breaking strength, breaking strain and tear strength. † Mechanization of Fibrous-Structured Cheese Production Process. Ill.

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Oxidation of cyclohexene by hydrogen peroxide was investigated by using as catalysts various heteropoly compounds having different central and poly atoms. The reaction scheme was proposed based on the time course of the oxidation of cyclohexene as well as the reactivity of the products, i. e., cyclohexene oxide and trans-1, 2-cyclohexanediol, and the stoichiometry of the oxidation of cyclohexene and cyclohexene oxide. The catalytic activity and selectivity-of 12-molybdop hosphoric acid for the oxidation of cyclohexene was affected by the presence of water. The catalytic activity of heteropoly acid increased with the increase in the valence of the central atom; B³⁺< Si⁴⁺ <c⁴⁺ p⁵⁺, and as for polyatom; Mo>W. These trends indicate that the catalytic activity increases with the increase of the redox potential of the polyanion.

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Hidasuki is a characteristic red pattern on Bizen-yaki and the iron components in Bizenclay are closely correlated with the red color of Hidasuki. Corundum is formed in Hidasuki. In this study, the effects of iron(III) oxide and potassium chloride on the formation of mullite and corundum were examined. Potassium chloride and/or iron(III) oxide were added to synthesized mullite and the mixtures were heated to 1300°. When the mixture of mullite and potassium chloride was heated, corundum was formed in addition to mullite. Regardless of the amount of added potassium chloride, the lattice constants of mullite and corundum were constant. Chlorine was not found in the products heated at above 900° When the mixture of mullite and iron(III) oxide was heated, corundum was not formed. The lattice constants of mullite increased with the increasing amount of iron(III) oxide. When various amounts of iron(III) oxide were added to the mixture of mulite and potassium chloride (weight ratio 1: 0.1), the amount of mullite decreased and that of corundum increased with the increasing amount of iron(III) oxide. The increases of lattice constants of mullite and corundum were due to the formation of solid solutionsof mullite-iron(III)oxide and corundum-iron(III) oxide.

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Effect of an additive on the reaction of zirconium(IV) dichloride oxide octahydrateotimes with j3-diketones and the reactions of [Zr(acac)₄] generated from ZrOCl₂ and acetylacetone with aliphatic alcohols (C₄-C₆) or phenols were investigated. Amines are the most efficient additive in the reaction between compound ZrOCl₂8H_°2 and β-diketone, especially triethylamine. The reaction of [Zr(acac)₄ ] with an excess of alcohols at 110-120°Cresult in the formation of the alkoxozirconium compounds: [Zr(acac)_4-n, (OR)_n] (n=2, 3), accompanied with bonds cleavage of the acac ligands. Reactions with phenol or the substituted phenols bearing NO₂, Cl, or CH₃, group at 110 ° in toluene give the corresponding bis(acetylacetonato)zirconiu m complexes: [Zr(acac)₂(0R)₂], but the reaction with the phenols having -COCH₃, or -OCOCH₃yield the tetraphenoxo compounds: Zr(OR)₄.

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Three eluents of benzoate, phthalate and 1, 3, 5-benzenetricarboxylate were investigated to separate seven sulfur species of sulfate, thiocyanate, thiosulfate, dithionate, trithionate, tetrathionate and pentathionate in their mixtures by suppressed ion chromatography with an anion exchange column (HPIC-AG4A, 50 mm x 4 mm i. d. ) and a conductivity detector. The flow-rate of the eluents was maintained at 3 ml/min and a 50-μl aliquot of the sample solution was used. Phthalate was more effective than benzoate, and so the phthalate eluent with the lower concentration could be used for the separation of each sulfur species from their mixtures.1, 3, 5-Benzenetricarboxylate was the most powerful as an eluent among the three eluents and caused the three sulfur species except dithionate and polythionates not to be separated from water dip, even when the 1, 3, 5-benzenetricarboxylate of low concentration (1 × 10^-5 mol/l) was used. Sulfate, thiocyanate, thiosulfate and dithionate could be separated by using 2× 10^-4 mol/l phthalate eluent (pH 5.7), and tri-, tetra- and pentathionate by 5 × 10^-3 mol/l phthalate eluent (pH 5.7). The high sensitivity of conductivity detection for sulfur species was achieved by using anion micro membrane suppressor (AMMS). The observed detection limits as S/N=3 were 1.83 × 10^-6 mol/ lfor SO₄^2-, 2.61 × 10^-6 mol/l for SCN-, 2.2 5 × 1 0^-6 m ol/l for S₂0₃^2-, 1.5 0 × 1 0^-5 m ol/l for S₂0₆^2-, 8.7 0×1 0^-6 m olf/ for S₃0 ₆²and 3.60 × 10^-5 mol/l for S₄0₆^2-, respectively. Calibration graphs plotted as peak heights vs. concentrations of sulfur species were linear up to 5× 10^-4 mol/l except for pentathionate.

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The reactions of 8-bromomethyl-1-methylisoquinoline hydrobromide 1 with sodium hydroxide and sodium alkoxide (alkoxide=methoxide, ethoxide, propoxide, and isopropoxide)gave the corresponding 8-hydroxymethyl and 8-alkoxymethyl 1-methylisoquinolines (3 a and 3 b-e), respectively. The reaction of 1, 8-bis(bromomethy)isoquinoline hydrobromide 2 with sodium alkoxides gave 1, 8-bis(alkoxymethyl)isoquinolines 4 a-d. The reactions of the compound 1 with ammonia and alky lamines (alkyl=methyl, ethyl, propyl, and isopropyl) gave 8-aminomethyl and 8-alkylaminomethyl-1-methylisoquinolines (5 a and 5 b-'e). On the reaction of the compound 2 with the same amines, the ring closure occurred to give 1 H-2, 3-dihydrobenzo[de][1, 7]naphthyridine derivatives 6a-e.

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The reaction of isocyanatosilanes Me_4-n Si(NCO)_n with ethanol in the presence of hydrochloric acid or triethylamine was investigated. In the absence of the additives the reaction with trimethylisocyanatosilane (TMIS, n=1) in the molar ratio (EtOH/TMIS =2) at 40°C in ether formed trimethylethoxysilane (TMES) in the yields of 2% (ca.1 mol/l), 10% (ca.2 mol/l) and 63% (without solvent) depending on the concentration of TMIS. In the presence of HCI, it was observed that trimethylchlorosilane and hexamethyldisiloxane were produced in addition to TMES (30-40% yield). In the presence of triethylamine, on the other hand, the reaction was found to form TMES in a quantitative yield (96%). On the basis of these results, the reaction with isocyanatosilan e (n=2, 3) in the presence of triethylamine was investigated to synthesize isocyanatosilane derivatives. The reaction proceeded smoothly at below 0 °C or more lower temperature to provide Me_4-nSi(NCO)_n-x⋅ (0Et), , (n=2, 3 and x=1, 2) in a good yield. In addition, silazane de rivatives [Me, Si⋅(OEt)]₂NH, [MeSi(OEt)₂]₂NH and [MeSi(OEt)NH]₃ were obtained by the reaction of the isocyanatosilane derivatives with ammonia.

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Rheological behavior of polymerized vesicle suspensions was studied by rotating viscometry. The suspensions showed Newtonian fluid, or non-Newtonian fluid-Bingham plastics at low concentrations. By increasing the concentration of vesicle, the behavior of the suspensions changed to non-Newtonian fluid-non-Bingham plastic. The Casson plots of polymerized vesicle suspensions showed linear realtion, and the value of Casson yield stress(S_c) was determined by extrapolation of the plots to the vertical axis. It was pos sible to estimate the degree of aggregation of vesicles from the value of S_c. The interaction of vesicles was enhanced by increasing the ionic strength or lowering the pH of suspensions. The aggregation of vesicles triggered by dextran-adding was dependent on the average molecular weight and the adding concentration of dextran.

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After the activation of polypropylene film by ozone-oxidation, methyl methacrylate was graft copolymerized onto it. The mechanism of ozone -oxidation and initiation of graft copolymerization was similar to that of the powdered polypropylene reported previously. The total conversion and the degree of grafting were smaller than those for the powdered polypropylene, on the other hand, the graft efficiency was nearly equal to it. The number of branch was 10^-2 order. The activation energy of the graft copolymerization was 11.9 kcal. mol^-1. Methyl methacrylate was graft-copolymerized onto uniaxially stre tched or simultanuously biaxially stretched polypropylene films in order to examine the influence of the inner structures on the ability of the graft copolymerization. The degree of grafting for stretched polypropylene film was higher than that for unstretched one. These results were discussed from the view points of cryst allinity, crystallite size, coefficient of orientation, content of the hydroperoxide, and the specific surface area.

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Amphiphilic cationic polyelectrolytes were obtained by the chemical modification of poly(allylamine)(PAA) with long alkyl chains and benzyl groups. These polymers showed highly surface activity and had compact conformation in aqueous solutions. This indicated the appearance of rigid hydrophobic domains similar to micelles formed by simple surfactants. In the present work, the structural effect of the polymeric amphiphilies on the hydrolysis of p-nitrophenyl acetate were examined. N-Octylated PAA and N-ben zylated PAA exerted the larger accelerating effect on the reaction than PAA. The higher the degree of substitution (D. S. ), the lower is the polarity of the polymer domain, and the higher the hydrolysis activity. It was suggested that the acceleration is controlled mainly by the concentration effect, and the more compact micellelike structure provides the hydrophobic reaction field, effective in including the substrate. In the case of N-dodecylated PAA, the less polar microenvironment of polymer mice lle was shown clearly even at D. S. =0.12. And the PAA derivative of D. S.≠ O.2, which has the hydrophobicity of E_T≠55 and lowest viscosity, exhibited the maximum catalytic activity. However, a higher D. S. decreased the rate of the hydrolysis; thus, the bulky dodecyl side groups are supposed to perturb the effective structure of the domain, resulting in the reduction of the capability to trap substrate molecules. On the other hand, the change in pH and the addition of ethanol or sodium chloride were found to influence the conformational structure of the polymers and their hydrolytic properties.

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Hydrolysis of gelatin by diluted hydrochloric acid has been believed to proceed through random breakdown of the polypeptide. This standpoint was examined through determination of the molecular weight distribution of the hydrolytic product of alkali-processed gelatin (isoionic point, pH 4.8; alpha-gelatin rich) by gel permeation chromatography using Asahipak GS-620 and GS-310 columns. The GPC chromatogram obtained at the middle stage of hydrolysis was bell-shaped, and agreed well with that drawn based on the theory of Sakurada and Okamura in which the hydrolytic rupture is assumed to proceed with equal probability for all main chain bonds linking the monomers.

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Thermal behavior of a synthesized hectorite-organic complex, which transforms to a porous material by heating the complex and removing the organic material from interlayers, were examined by thermal, specific surface area (SSA), infrared spectra (IR) and X-ray diffraction analyses. This complex was made from a hydrothermally synthesized hectorite and dialkyldimethylammonium ion having mainly octadecyl group as alkyl. The largest SSA was obtained in a sample heated at 600 °C. This temperature corresponds to that the IR absorption bands originated in alkyl chain of organic ion disappear. Pores of the porous material were, therefore, considered to be formed by eliminating the organic ion, which acted as a template, from hectorite interlayers. Products of heating the alkyl group depended on the atmosphere; under nitrogen flow, the alkyl group decomposed into hydrocarbon gases to volatilize at relatively low temperature, about 400 °C. Under air flow, on the other hand, oxides showing C=O IR absorption band were generated about 400 °C and remained in the interlayers up to over 700 °C. The dehydroxylation of the organic comple x shifted about 90 °C to higher temperature than the synthesized hectorite. As N-H bending vibration band was recognized in IR spectra of specimens heated between 400 and 700°C, ammonium ion balanced the charge with silicate negative charge and, consequently, contributed to the thermal stability of a produced porous material.

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A simple and rapid method for determining trace amounts of phosphate in aquatic environment was proposed. A O.5 ml portion of 1 mol. dm^-3 iron(III) nitrate solution and 0.3 ml of 1 mol. dm^-3 bismuth(III) chloride solution were added to a 1 l of test solution, and the pH was adjusted with sodium hydroxide in the range from 7 to 8 to precipitate mixed hydroxide of iron(III) and bismuthan(III) with which phosphate coprecipitated. The suspension was stirred for 30 min and filtered through a 1 μm membrane filter. The precipitate on the filter was dissolved in 5 ml of 5 mol⋅dm^-3 sulfuric acid and then 6ml of 10mol⋅dm^-3 sodium hydroxide was added to the solution to release the phosphate from the regenerated precipitate. The total volume of the suspension and washings was made up to 20 ml with distilled water and stirred for 10 min. After centrifugal separation, the pH of the solution was adjusted from 3.0 to 4.0 with sulfuric acid and ammonium molybdate and tin( II ) chloride were added to develop a blue color. The absorbance was measured at 710 nm. Phosphate as low as 3 ppb could be determined. Up to 60 ppm of silicate did not interfere. The method was applied to the determination of phosphate in river water samples.

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Hydrogen isotope exchange raction between HTO vapor and one of the sodium salts of a-, m-, and p-aminobenzoic acid (solid) was observed at 50-80°C. The acidity (acidity based on kinetic logic) for the materials at each temperatur has been obtained with the A"-McKay plots based on the respective data obtained. The followings have been clarified by comparing these acidities (and the acidities obtained previously).1) The acidity of aromatic amines can be expressed in terms of the acidity based on kinetic logic.2) The reactivity of aromatic amine is strongly affected by both I-effect and R-effect.3) It can be deduced that aromatic amines are more reactive than aliphatic amines.

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Transformation of tetrabutylphosphonium bromide, whic h worked as a phase transfer catalyst in chloride-fluoride exchange reaction of 1, 2-dichloro-4-trifluoromethylbenzene using potassium fluoride, was investigated by ¹³C- and ³¹P-NMR. The phosphonium salt exclusively changed into tributylphosphine oxide in the halide exchange reaction. About 10% of the catalyst turned into the phosphine oxide through dehydration at 150°C for 3 h and halide exchange reaction at 185 °C for 16 h. After the reaction was repeated five times, approximately 50% of the phosphonium salt remained. The residual amount of the phosphonium salt had good correlation with repeated number of the reaction.

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In order to understand the behavior of chromium at the confluence of the river and sea waters, the surface distributions of several chromium species have been investigated at the Ibo River with the influence of tannery effluents and Harima Nada (see Fig.1). The concentrations of particulate Cr, dissolved inorganic Cr (III) and dissolved organic Cr(III) gradually decreased from the upper stream in the Ibo River to the estuary, rapidly decreased from the estuary to O.5 km offing from the estuary and gradually decreased from O.5 km to 20 km offing from the estuary. These results indicate that the chromium species in the river waters rapidly diffuse into and are diluted with the sea water near the estuary. The concentrations of Cr(VI) in the sea waters at several sites fell within a narrow range (0.06-0.11 μg/l).

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