Crystal structures of modified cyclodextrins and inclusion complexes have been investigated by the X-ray method. The round macrocyclic conformation of native cyclodextrins is maintained by intramolecular hydrogen bonds formed between 2-OH and 3-OH of an adjacent glucose unit. The cylindrical cavity of cyclodextrin is defined by the diameter and depth and accommodates guest molecules having suitable size and shape. The macrocyclic conformation is not significantly affected by the modification of a primary hydroxy group. In the crystal, the substituent group is found to be inserted into the adjacent cyclodextrin ring. Even when all 2-OH and 6-OH hydroxy groups are methylated, cyclodextrins still maintain the round structure because of the formation of intramolecular 3-OH…O-2hydrogen bonds. However, the cavity is extended by the methyl groups attached at both edges of the cylindrical molecule. As a result, the disposition of the guest molecule in the host cavity is not the same as that in the corresponding native cyclodextrin complexes. In contrast, when all the hydroxy groups are methylated, the macrocyclic ring is free from the restraint imposed by the intramolecular hydrogen bonds, and therefore becomes more flexible. The macrocyclic ring changes its conformation to obtain better fit to the shape of the guest molecule. The effect is prominent in the recognition of chiral molec ules in the crystalline complex.

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A new class of vinyl-functionalized polysiloxane-block-polyimides was synthesized and characterized. The copolyimides were derived from 4, 4'-carbonyldiphthalic anhydride/bis [4- (3-aminophenoxy) phenyl] sulfone combined with two kinds of vinyl-containing diamino (poly) siloxanes and imidized by solution method. They were highly soluble in various organic solvents. The vinyl groups of the copolyimides were reacted with various hydrosiloxane compounds for crosslinking. The crosslinked products became insoluble in polar solvents and were analyzed and characterized by TMA, DMA, and ¹³C- and ²⁹Si-NMR. On the other hand, silicate-containing copolyimides could easily be derived by hydrosilylation of the copolyimides having vinyl groups and diethoxymethylsilane. The copolyimides containing silicate finally obtained were soluble in various organic solvents and easily hydrolyzed to give crosslinked copolyimides during the solution casting to prepare their films. The resulting materials have various potential applications as the new organic-inorganic materials.

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In recent years, several kinds of adhesive films have been developed and applied in aerospace and electronic industries. Processability at moderate conditions, high initial lap shear strength, durability under high humidity and high temperature conditions are major requirement in their applications. Recently, the polyimide adhesives have been also applied in microelectronics and printed wiring boards industries in Japan. However, they ought to be processed at high temperature (>300 °C) and pressure (>20MPa) due to the low fluidity. In this work, the relationship between structure and single lap shear bond strength of various polyimides were studied for developing the polyimides suited as film-adhesives with good processability and adhesive strength. It was found that the polyimides derived from 4, 4'-carbonyldiphthalic anhydride (CDPA) and bis [4- (3-aminophenoxy) phenyl] sulfone (BAPSM) exhibit excellent lap shear strength at room temperature. In addition, various kinds of polysiloxane-block-copolyimides were synthesized and examined as film-adhesives to study the effects of polysiloxane incorporation into aromatic polyimides on the initial lap shear strength. The all of copolyimides containing 10 wt% of polysiloxane were found to have excellent lap shear strength, despite the difference in aromatic components. Their adhesive durability under a highly humid condition (25 °C, 90%RH) was also improved mainly due to their lower moisture sorption and lower moisture permeability. However, further incorporation of polysiloxane into polymer backbone gradually lowered the initial lap shear strength and the durability.

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The transmission and emission spectra of plastic containing Riboflavin tetrabutyrate (RTB) showed that the effect of concentration and thermal gradient on the transannular interaction between th e isoalloxazine (IA) rings could be divided into three clases. The diference in energy between the interacting IA rings and the isolated ring of the S_o s tate were estimated to be nearly the same as the excitation energy for the following vibrational motions, 1. A vibration of III, IV, V, VI of amid absorption band or single bond of t he side-chain lowar than 1450 cm^-1, 2. Combination tone of v ibration of 1V, V or VI o f amid absorption band and skeleton of the IA ring of 2000-2500 cm^-1, 3. A harmonics of the skeletal vibrration of the IA ring, that is, (1500 or 1600 cm^-1) × vibrational quantum number.
Differences in the energy state correspond to the changes in conformation m entioned below. 1. The formation of a contact complex of two IA r ings. 2. The formation of a overlapped dimer at the IA ring. 3. Shortening of the distance between the IA rings to form a tightly overlapped dimer.
These changes in conformation suggest that the tansformation of the RTB molecule with increases in concentration or thermal gradient is due to vibrational excitation at specific bonds.
First, the distance between hydrogen bonds is shortened with increasing c oncentration, which then changes the conformation of the side-chain. At this point, however, the relative orientation of the IA rings is random and unfolded.
As the concentration continues to increase, the IA rings overlap each other and the ring distance becomes shorter.
As the result of the occurrence of thermal gradient in plastic with polymerizaton of methyl methacrylate, step by step the IA rings reach higher levels of skeletal vibration, and the rings become closer and closer.
The charge transfer interaction of the S_o state is promoted by the acceleration of the transannular interaction and RTB at last quenches its emission.

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Gel-composite electropolymerized films were prepared by means of combination of the electropolymerization and sol-gel methods. Monomers such as aniline, thiophene and pyrrole were electrooxidatively polymerized in acidic solutions of metal alkoxides [ (EtO) ₄Si and (n-BuO) ₄Ti] . The polymerization and gelation could take place simultaneously on the anodes to form the stable, uniform and electroactive films, when composition and acidity of the solutions were optimized. From SEM and EPMA observations, it was confirmed that gel components are uniformly dispersed in the polymer matrices. The films thus prepared were characterized by their unique electrochemical and mechanical properties such as redox responsibility, electrocatalytic activity, potential window, durability, etc.
Introduction of gels as insulators into the films did not cause any considerable decrease in their electroconductivity and stability on repeating potential sweep, though their elecroactivities (redox responsibility) were somewhat decreased. A substrate-selective electrocatalytic activity was observed in the electrochemical redox reaction of Fe (II/ III) species on an electrode coated with a titanium oxide gelpolyaniline composite film.337

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We have carried out the feasibility study on the contact decomposition of NO by metal complexes such as metallotetraphenylporphyrins (MTPPs: M = Co (II), Cr (III), Zn (II), Ag (II), Ru (II) ) and Co (salen). Firstly, the NO adsorption properties of these metal complexes were evaluated by UV-vis and FT-IR spectroscopy. Among these complexes, both CoTPP and Co (salen) showed excellent NO adsorption ability. Two kinds of NO- species adsorbed on the center metal ion were observed for both CoTPP and Co (salen), and a new peak (1528 cm^-1) which was assigned to a bridging NO between two adjacent NO^- molecules appeared gradually for Co (salen) by the exposure to NO at around 1000 ppm. In the case of CoTPP, the bridging NO was observed by the exposure to NO of higher than 1 %.
Secondly, the contact decomposition properties of NO were investigated using CoTPP and Co (salen). These complexes were impregnated with porous glasses and employed as catalysts. Main decomposition species were N₂0 and N₂. The performance of the NO decomposition by Co (salen) was better than that of CoTPP. The maximum efficiency of NO decomposition at 190 °C by Co (salen) was 84% for inlet gas (NO: 300 ppm, O₂: 0.9%, in He). These results indicate that the NO contact decomposition is possible under O₂ coexistence condition without any reduction reagent.

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Synthesis and physiological activity of amides, sulfides and thiocyanates with an ionone residue was examined. α- and β-Ionones 1, 2 were converted to primary amines by a convenient method, followed by succesive reaction to afford objective amides, sulfides and thiocyanates. lonone 1 and 2 were converted to primary amines by oximation with hydroxylamine hydrochloride, followed by reduction with lithium aluminum hydride. These primary amine derivatives were finally transformed into amides lc-2f, sulfides 1h-2i and thiocyanates 1j-2j.
Sixteen ionone derivatives obtai ned were tested the efficiency for growth-regulating activity toward plants and antimicrobial activity. As activity of the former toward Lactuca sativa L., cv New York, lh-2h at 100 ppm indicated an inhibition of ca.90% toward root growth. As activity of the latter toward Bacillus subtilis (B. subtilis), Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), Aspergillus niger (A. niger), Penicillum citrinum (P. citrinum) and Fusarium oxysporum (F. oxysporum), 1, 1-Diisopropyl-3-{ (E) -1-methyl-3-[(R)-2, 6, 6-trimethyl-2-cyclohexen-1-yl] -2-propenyl} urea (1e), { (E) -1-methyl-3-[ (R) -2, 6, 6-trimethyl-2-cyclohexen-1-yl] -2-propenyl} aminomethyl thiocyanate (1j) and { (E) -1-methyl-3- [ (R) -2, 6, 6-trimethyl-2-cyclohexen-1-yl] -2-propenyl}aminomethyl thiocyanate (2j) (at0.01-0.001μg/mL) derived from 1 and 2 completely inhibited the growth of A. niger, P. citrinum and F. oxysporum.

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Catalytic degradation of polyethylene was carried out at 400 °C by the fluidized reactor with various catalysts. Oily liquid product consisting of hydrocarbons of carbon number up to ca.20 was pro duced over the catalysts of silica-alumina and the silica-alumina treated with sulfuric acid and Y-type zeolite, but over the catalysts of iron, nickel and copper supporting on silica-alumina the residue containing relatively a large amount of carbon was produced.
When the degradation was carried out over the silica-alumina catalysts at the temperature range from 350 to 700 °C, the largest amount of the liquid product was formed at 450 °C. W axy product was formed at 350 °C, but not over 370 °C and the amount of the gaseous product increased at 600 °C and 700 °C, respectively.
The fo rmation of carcinogenic product, i. e., benzo [a] pyrene, was detected in all the reactions carried out over any kind of catalyst examined and its amount increased with increasing the degradation te mperature. The formation of other kinds of products such as naphthalene, pyrene and fluorene was also detected.

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Magnetic susceptibility measurements for the aqueous iron (III) -triethanolamine (TEA) systems of [iron (III) ion] =2.5 mM ( 1 M=1 mol dm^-3) and R= [TEA]/ [iron (III) ion] ≥ 20 in a wide pH range 1 to 13 at room temperature have been carried out by the Gouy method with much attention to precipitation reactions in these solutions. It has been revealed that, at pH 3-7, TEA scarcely solubilizes iron (III) hydroxide-like clusters, while, at pH> 8, it strongly coordinates to an iron (III) ion with its deprotonated hydroxyethyl group and finally forms some stable and soluble mononuclear iron (III) complex with a TEA/Fe ratio of 2 or 3. It appears well established that the masking of iron (III) ions by TEA in analytical chemistry is identical with the formation of the above-mentioned mononuclear iron (III) complex in alkaline media.

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It was investigated by cyclic voltammetry that the titled [amino (carboxy) phthalocyaninato] cobalt (II) can work more effective on the decomposition of acetaldehyde than (polycarboxyphthalocyaninato) iron (III) from the point of electrochemical interaction. It is already reported that (polycarboxyphthalocyaninato) iron (III) has catalytic activity on the decomposition of acetaldehyde as if it works like enzyme catalase; however, phthalocyaninatoiron (III) has a crucial problem that it is easily deteriorated via, μ-oxo dimer in basic solution. In addition, from our practical experiments by the measurements of odor-decay with gas inspection tubes, (tetracarboxyphthalocyaninato) cobalt (II) did not work on the decomposition of acetaldehyde. We propose in this article that the titled [amino (carboxy) phthalocyaninato] cobalt (II) could be a practical odor-remover against acetaldehyde included in tabacco odor.

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Catalytic dehalogenation of organic halides was carried out in a 2-propanol solution of NaOH with Pd/C at temperatures below 82 °C. It was found that the aliphatic halides were converted to the corresponding halogen-free hydrocarbons with high yields, although the reaction rate was much slower than that of aromatic halides. Among the substrates containing I, Br and Cl, the order of dehalogenation rate was I>Br>Cl. The halogen at the terminal position of the carbon chain was easily dehalogenated rather than the internal halogen.

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