This article describes the results of the recent attempts to study the mechanisms of chirality recognition on a silicate surface of a clay meneral. As a first attempt, the liquid column chromatography has been performed on a column packed with an ion-exchange adduct of a metal chelate and a clay. The intermolecular interactions between an adsorbed chelate and a resolved molecule are affected greatly by the hydrophobicity and the steric structure of a ligand of a chelate. Next is described the Monte Carlo simulation of the intercalation of a tris (1, 10-phenanthroline)metal (II) between the model silicate sheets. The theory predicts well the chirality effects on the formation of adsorption layer of the chelate. As a third attempt, the photochemical behaviour of tris (2, 2'-bipyridyl) ruthenium (II) is studied when the chelate is bound by a colloidally dispersed clay particle. From the effects of chirality on the intensity and life time of the fluorescence, it is concluded that the chelate has a tendency to aggregate as a racemic pair rather than as a pure enantiomer. As a fourth attempt, the quartz crystal microbalance method is applied to study the mass transfer on a clay modified electrode. It is revealed that some bound tris (1, 10phenanthroline)ruthenium (II) is dissociated during the electrochemical oxidation. Lastly it is attempted to form a monolayer of clay at the air-water interface. The LB film is prepared by transfering the clay monolayer on a glassy carbon substrate. The film provides a unique modifier when it is used as an electrode.

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Various ZSM-5 type zeolites having different crystal sizes with Si/Al ratio of 80 were synthesized by varing the synthesis time and the OH^-/SiO₂ ratio in the synthesis mixture. The steaming durabilities, the themal durabilities and the catalytic activities for methanol conversion were investigated. The crystal sizes were hardly influenced by the synthesis time, but strongly influenced by the OH^-/SiO₂ ratio in the synthesis mixture.
The large cr ystallites synthesized at the OH^-/SiO₂ ratio of 0.14 had larger amount of acidic sites after steaming than smaller crystallites. The structure of ZSM-5 crystallites was destroyed at a temperature of 1373 K or above, and transformed to the cristobalite structure at 1473 K. The destruction temperature of large ZSM-5 crystallites was higher than that of smaller ZSM-5 crystallites. The conversion of methanol to hydrocarbons decreased with an decrease in the amount of the strong acidic sites by steaming.

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Acidic properties of dealuminated Mordenite treated by hydrochoric acid were characterized by TPD method and isomerization reactions of butenes. The ratio of a luminum contents and th e strong acid amounts in Mordenite is a lmost 1: 1 in the ranges of SiO₂Al₂O₃, 35∼70, and when the ratio of SiO₂Al₂O₃ deviates from these values, the strong acid amounts do not correspond to aluminum contents. The ratio of the weak acid amounts and the stro ng acid amounts is about 1: 2. Since heats of adsorption of NH₃ are 149±2 kJ/mol in all ranges of SiO₂Al₂O₃, it is suggested that the sti-ength of the acid is independent of aluminum contents.
Desorption products of C₃H₆-TPD are dependent on SiO₂Al₂O₃ ratio of Morde nite. In small ratio of SiO₂Al₂O₃, propene molecules are adsorbed directly on the acid sites and desorbed with production of normal hydrocarbons which are produced by interactions between adsorbates. In medium ratio of SiO₂Al₂O₃ oligomers are formed on the acid sites and they are desorbed producing branched isomers.
In the isomerization reactions of butenes, the Mordenite having the larger amount of the acid reveals the higher catalytic activity. The catalytic activity is higher in the isomerization reaction of buten es, as amounts of the acid of Mordenite are larger, but the acid strength of t he catalyst is n ot influenced by t h e amounts of the acid.

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Electronic absorption spectra of bis (salicylaldehydato) Cu (II ) (Cu (II)(sal)₂) in ethanol, and pola. - rized absorption spectrum of Cu (II )(sal)₂ in a stretched PVA film have been measured to clarify the molecular structure and nature of the electronic transitions of the complex in comparison with MO calculations. In the MO calculations for Cu (II )(sal)₂, the central metal ion (Cu (II)) is treated as a point charge ( + 0.3 e) to consider its effect on the 7r-electronic systems of the ligands (sal) and the interaction between n-electronic systems of two ligands is evaluated by resonance integrals between nearest neighbor oxygen atoms. While Cu (II )(sal)₂ is stable in a crystalline state, it dissociates partially in a solvent such as ethanol. The absorption spectrum of pure Cu (II )(sal)₂ in ethanol computed by simulation shows, besides a very weak and broad band at 648 nm assigned to a forbidden dd transition of the central metal, peaks or shoulders at ∼420 (detected by polarized absorption spectrum), 385, 308, 274.4, 241, and 224 nm. The 385, 274.4, 241, and 224 nm bands are assigned to electronic transitions localized on the ligand (sal), and the ∼420 and 308 nm bands are originated from the intramolecular charge transfer transitions between metal and ligand, and between metal and ligand or between the two ligands, respectively. Cu (II )(sal)₂ is found to take a structure where two ligands of sal are in a trans-like configuration with respect to the central metal.

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A standard addition method with an ion-selective electrode which does not require the adjustment of the ionic strength of a sample is proposed.
After the sample, of volume V, is titrated with the first standard solution containing the analyte ion of a known concentration (c_S1), the sample solution of a certain volume V⁰ is added. Subsequently it is titrated with the second standard solution of a known concentration (c_S2) having the same ionic strength as that of the first standard solution.
If the electromotive forces, E₁ and E₂, which correspond to the titration volumes, vsi and vs2, by the first and second standard solutions that satisfy a condition of υ_S2 =υ_S1( V+ V⁰) / V-υ_S1⁰ are read off respectively on the two titration curves, the concentration, c_x of the analyte ion is determined from the slope of a linear plot of y vs. x (vυ_S1⁰ is the final volume of the first standard solution added):
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Concentrations of th e fluoride ranging from 10^-3 to 5×10^-5 mol⋅dm^-3 in the samples of various ionic strengths were determined with an error of less than 0.4% and a relative standard deviation of less than 0.5%.

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1, 2, 5, 6-Tetrahydro-1, 2, 3-triazine derivatives (8) which have a new skeletal ring were obtained in moderate yields by the rearrangement of cis-N-alkyl-3-phenylaziridin-2-yl phenyl ketone semicarbazones (3) with diethyl ether-boron trifluoride (1/1) (7) in dichloromethane. Starting materials 3 were formed in nearly quantitative yields by the condensation of cis-N-alkyl-3-phenylaziridin-2-y1 phenyl ketones (1) with semicarbazide (2) hydrochloride in pyridine at room temperature. Usual conditions (weakly acidic and heating) offered 3 in low yields for the decomposition of 1.

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The carbazole derivatives (5a, b and 9a, b) including isoquinoline skeleton were synthesized via bromo or nitro substituted 1, 8-dimethylisoquinoline (1a) and 5, 6-dihydro-4H-benz[de]isoquinoline (lb). The reaction of la with N-bromosuccinimide (NBS) in concentrated sulfuric acid gave the 5-bro mo compound 2a, which was subjected to Ullmann reaction with acetanilide in the presence of copper, iodine and potassium carbonate to give the 5-acetamide derivative 3a. Then 3a was subjected to hydrolysis in hydrochloric acid to provide the anilino derivative 4a, and finally, the carbazole derivative 5a was obtained by heating 4a in acetic acid in the presence of palladium acetate. The carbazole derivative 5b was prepared from lb by the same procedures.
On the other hand, the reaction of la with potassium nitrate in concentrated sulfuric acid gave the 5nitro compound 6a, which was reduced in hydrochloric acid by tin (II) chloride to provide the amine 7a. Then, the diazotization of 7a with sodium nitrite followed by the reduction with tin (II) chloride gave hydrazine 8a. Finally, the reaction of 8a with cyclohexanone in methanol provided the carbazole derivative 9a. The carbazole derivative 9b was prepared from lb by the same procedures.

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The dependence of growth parameters (deposition temperature and gas composition) on the deposition rate of tungsten nitride was studied by chemical vapor deposition (CVD) under low pressure. Tungsten nitride was deposited on a silicon (100) substrate in a gas mixture of WF₆-NH₃-H₂ (in Ar) at 0.12 kPa. The tungsten nitride films were analyzed by scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The film of tungsten nitride was formed at temperatures of 250to 800°C. Amorphous W₂N was formed at lower temperatures, but W₂N (200) and (111) faces were preferably orientated on to silicon (100) above 500 C. The apparent activation energy was 62 kJ/mol at the temperatures of 250 to 400°C. The reaction orders for W₂N deposition were 1.0, 0.65 and 0 with respect to WF₆, NH₃ and H₂, respectively. From these results, the formation of tungsten nitride is considered to be more limited by surface reaction of WF₆ with NH₃. The film growth rate for tungsten nitride is as follows:

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Reactions of p-benzoquinone (1) with /V, N-dimethylaniline (2a), /V, N-diethylaniline (2b), N, Ndimethylm-anisidine (2c) and /V, N-diethyl-m-anisidine (2d) were carried out. The corresponding monoarylated p-benzoquiones (3) were obtained and diarylated p-benzoquinones were also obtained from reactions of 1 with 2c and 2d. Furtheremore, using a variety of subsutituted p-benzoquinones (5)(subsutituent: a: MeO; b: F; c: Cl; d: COMe; e: COPh; f: COOMe; g: CN; h: Ph; i: p-O₂NC₆H₄), 2-[4-(dimethylamino) phenyl] -p-benzoquinone (3a), 2- [2-methoxy-4- (dimethylamino) phenyl] -p-benzoquinoe (3c), 2, 5- and 2, 6-dichloro-p-benzoquinones (10, 11), same reactions were carried out. Reactions of monosubstituted p-benzoquinones with 2 are susceptible to the natures of those substituents, occurred at 5-position in case of 5a-c, 3-position in csae of 5d-g and 6-position in case of 5h, 5i, 3a and 3c, respectively. It was confirmed by an isolation of the corresponding intermediate hydroquinones in case of 5d-f that reactions in this work proceed via a Michael 1, 4-addition.

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The behaviour of shrinkage stress during oxidation and carbonization of polyacrylonitrile (PAN)fibers was studied under various conditions, such as tension and oxidation time, and the effects of these conditions on tensile properties of resultant carbon fibers were discussed. The shrinkage stress during carbonization of the fibers oxidized at 255°C under the tension of 10∼100 mg/d was found to decrease with heating temperature up to 420°C (region III) and then increase (region IV). This behaviour of shrinkage stress of oxidized fibers in the regions III and IV depended on the crystallite orientation, chemically-bound oxygen and stabilization index SI. To produce carbon fibers of high tensile strength with high productivity, it was preferable that the oxidized fibers with the chemically-bound oxygen of about 8 wt%, corresponding to SI value of about 80%, and the degree of crystallite orientation of 76%were carbonized under a tension of about 250 mg/d in the regions III and IV.

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The surface and internal defects of the fibers, such as coalescence of fibers, cavitation in the fiber and formation of micropores, are known to govern the tensile properties of the polyacrylonitrile (PAN) based carbon fibers. The precursor PAN fibers were sized with two kinds of the process oil, oxidized under two steps oxidation conditions and then carbonized at various heating rate. Stabilization degree SI and chemically-bound oxygen of the oxidized fibers, density and tensile properties of the carbon fibers were measured. The effects of process oil and heating conditions on the formation of defects and tensile properties of the resulting carbon fibers were discussed. In order to produce carbon fibers with less surface and internal defects, as a consequence having high tensile strength, it was preferable that the oxidized fibers with the chemically-bound oxygen of about 8% using polydimethylsiloxisane as a process oil were carbonized at the heating rate below 15°C/s.

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Polyacrylonitrile (PAN) -based carbon fibers with the thermal oxidative stability (TOS) as well as the interlaminar shear strength (ILSS) are very useful for high-temperature resin composites. The effects of the process conditions, such as the heat-treatment temperature, the surface treatment and the additives, on weight loss, tensile properties and surface characteristics of the fibers were studied after oxidized in the air by using thermogravimetry, SEM, ESCA and laser Raman. The results indicated that oxidation weight loss of the fibers was decreased with elevating the heat-treatment temperature, but increased by the surface treatment. It was also recognized that the growth of the crystallites of graphitelike layers in the fibers caused to make the pits with the sharp edges on the surface by oxidation in air. To get the carbon fibers with high TOS and good ILSS, it was preferable to treat the surface of carbon fibers by electrolysis method in phosphoric acid at less than 1600°C.

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To improve the the functional properties of Nylon-6, several s-triazine compounds with phenoxy substituents were reacted with Nylon-6 at its melting conditions. Especially, triphenoxy-s-triazine was found to react with the terminal amino groups of Nylon-6, without decreasing the original relative viscosities of Nylon-6, if its molar ratio relative to the terminal amino groups was 1-1.2. From the model reaction of triphenoxy-s-triazine and octadecylamine, the rate constants of the three phenoxy groups of tris (p-substituted phenoxy)-s-triazines were determined, the Hammett plot for different substituents produced a strait line with a positive slope p, indicating a nucleophilic reaction. Since the triazine groups introduced in the terminal amino groups of Nylon-6 has residual phenoxy groups, they can be used as the site of other functionalization. This technique is possively applied to production of industrially new type Nylon fibers or plastics which have several functional properties. t Studies on Functionalization of Polymers by Reactive Processing. I.

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Reduction of 4-trichloromethy1-4-methyl-2, 5-cyclohexadien-1-one (1) and 4-dichloromethy1-4methy1-2, 5-cyclohexadien-1-one (7) by the use of bakers' yeast was studied. Reduction of 1 proceeded at the C = 0 bonds electiveltyo h ivec -4- andt -4-trichloromethy1-4-methyl-2, 5-cyclohexadien-r-1-ol (c- 4: t-4=42: 58). On the other hand, 7 was reduced to c-4-and t-4-dichloromethyl-4-methyl-r1-cyclohexanol (c- 4: t- 4 =72: 28) through cyclohexen-1-one (8) and cyclohexanone (9). The reduction of 4-trichloromethyl-4-methylcyclohexanone (4) proceeded more stereoselectively to afford c-4-and t-4-trichloromethyl-4-methyl-r-1-cyclohexanol (c- 4: t- 4 =97: 3).

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Transformation of 4-hydroxybutyl vinyl ether (HBVE) in an acidic medium was investigated by GCMS and ¹³C-NMR. The ether monomer was copolymerized as bridging group in solvent-soluble fluoropolymer. The monomer changed into intramolecular 7-membered cyclic compound, 2-methyl1, 3-dioxepane and linear oligomers in intermolecular addition of vinyl and hydroxy groups when the monomer modified with dilute hydrochloric acid. The transformation proceeded fast in acid, though it progressed slowly by heating and did not in alkali at all. Practical paints modified with succinic anhydride contained the linear oligomers originated from unpolymerized HBVE monomer.

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