The authors found out that some polymethacrylate esters and polysaccharide derivatives exhibited good chiral recognition as a stationary phase for liquid chromatography. By coating these polymers on silica gel, practically useful HPLC columns were developed and twelve ones have been marketed. Then a preparative liquid chromatography system equipped with a large scale chiral separation column was also established and the commercial optical resolution service by HPLC was started for the first time in the world.
In this account, some technological and scientific points in the development and the scope for the further development are described.

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The physical properties of 3-butylsydnone at various temperatures were investigated by dielectric constant, refractive index, density and viscosity measurements. The dielectric constant (ε) were obtained by 1 MHz and 300 kHz. The dielectric constant at 1 MHz at any temperature is about 2-3 larger than that at 300 kHz (Fig.2). For example, these values at 25 °Cwere found to be 77.9 and 75.1, respectively. Both dielectric constants at the given frequencies for 3-butylsydnone are approximately expressed by the cubic equations of temperature. The refractive index (n D) and density (ρ) for 3-butylsydnone decrease linearly with increase of temperature (Figs.4 and 6). The linear relationship between εand nD² is found in a range from 15 to 60 °C(Fig.5). The Kirkwood equation for 3-butylsydnone holds over the range from 10 to 80 °C(Fig.7). The viscosity (η) of 3-butylsydnone decreases markedly with increase of temperature, as shown in Fig.8. In addition, it seems that the viscosity of four kinds of 3-alkylsydnone becomes equal at higher temperature. A plot of logη vs.17 for 3-butylsydnone gives a straight line. The activation energy of viscosity for 3-butylsydnone calculated from the slope of the line was found to be 29.3 kJmol^-1

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Ti0₂-SiO₂ and Ti0₂-Al₂0₃ binary oxides were prepared by simultan eous hydrolysis of a mixed solution of the respective metal alkoxides, and relationship between the structures and the surface properties of the binary oxides was studied. Both binary oxides calcined at 773 K were foun d to form finely-divided Ti0₂ particles by XRD and EXAFS measurements and to have strong acid sites on the surfaces. Ti0₂ particles in the Ti0₂-Al₂03 were observed to grow with the elevation of the calcination temperature and transformed from an anatase to a rutile structure at about 973 K. While in the Ti0, Si0₂, the growth of TiO₂ particles as well as the phase transformation was strongly suppressed even after a calcination at 1273 K, suggesting the presence of some interactions between the Ti0₂ and SiO₂ particles. The types of acid sites generated on the binary oxides were m easured by infrared spectroscopy of pyridine adsorbed on the surfaces. The results showed that only Lewis acids, sprung from pure TiO₂ and Al₂0₃ particles still remained on the Ti0₂-Al₂0₃, whereas BrOnsted acids were created on the Ti0₂-Si0₂. The generation of the BrOnsted acid sites is considered to be ascribed to the interactions between the component oxide particles in the binary oxide, probably originated in Ti-O-Si bonds. The isomerization of 1-butene was remarkably accelerated by the presence of the BrOnsted acid sites on the surface of Ti0₂Si0₂.

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In order to analyze H₂-O₂-SiCl₄ combustion flames, a simplified and widely appl icable calculation method was proposed to evaluate adiabatic temperatures and also to evaluate partial pressures of materials existing in the flames. Generally, it becomes very complicable to evaluate them when the more kinds of metarials exist in the combustion flames. In this study, starting values adopted on the calculations were giv en based on the main reaction in the H₂-O₂-SiCl₄ combustion flames. Succesively, multiple simultaneous equations to solve were separated into two groups of liner and non-liner ones and attempted to be solved. Thus, an iteration between these two groups was converged, and adiabatic temperatures and partical pressures of the materials were possible to be evaluated easily. Furthermore, the results of calculated adiabatic temperatures were applie d to an analysis of actual H₂-O₂-SiCl₄ combustion flames which generate fumed-silicas. Properties of fumedsilicas generated were examined in relation to adiabatic temperatures which were considerd to be almost the same as actual flame temperatures judging from few results of temperature measurements using CARS methods. As a result, specific surface areas, apparent refractive index and number of hydroxyl groups which characterize properties of fumed-silicas changed dynamically around temperatures corresponding to melting point of SiO₂ (1873-1986 K). We concluded that this resulted from a different formation process of silica primary particles dependent on temperatures. At a temperature lower than melting point, numerous pores exist inside and outside primary particles because particles have formed in a non-melted phase. On the other hand, at higher temperatures particles were assumed to have formed in a melted phase and thus they hardly include pores.

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Studies on the heating process of a mixture of halloysite and potassiu m iodide were carried by TG-DTA, X-ray powder diffraction and mass spectrometry. Halloysite reacts with potassium iodide at its dehydroxylation temperature (-500°C) to generate H20, HI and H2I2. Halloysite (1.0 mol) react with up to 2.2 mol of potassium iodide completely. When above 2.4 mol of potassium iodide is added to 1.0 mol halloysite, excess potassium iodide me lt at 667°C and then evaporate completely below 800°CC. Among potassium halides (KC1, KBr, KI) the largest reaction with halloysite is potassium iodide. A mixture of 2.0 mol of potassium iodide and 1.0 mol of halloysite forms kaliophilite (KAlSia, ) at 1090°CC. The kaliophilite decomposes into leucite (KA1Si206) and corundum (Al203) after above one hour of heat treatment at 1300°C, as the following reaction.
4 KAlSiO, ₂ KA1Si₂0₆ + Al₂0₃ + K₂0
Considering decrease of K20 content and weight loss in heated products, it may be concluded that K20 evaporate at this temperature. When quartz is added to a mixture of 2.0 mol of potassium iodide and 1.0 mol of halloysite, kaliophilite once produced reacts with quartz at 1300°C to form only leucite.

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Cycloaddition reaction of mono-substituted epoxides with benzal dehydes was investigated using quaternary ammonium salts as catalysts. The reaction of phenoxymethyloxirane (PMO)and benzaldehydes with electron withdrawing groups proceeded smoothly to give the corresponding 2, 4-substituted-1, 3-dioxolanes in high yield, while benzaldehydes with electron donating groups did not react. Furthermore, it was found that the reaction proceeded stereoselectively, and trans-dioxolanes were preferentially obtained. The cycloaddition reaction was smoothly proceeded in nonpolar solvents such as toluene or tetralin. The catalytic effect on the cycloaddition reaction was shown in Figs.1 and 2. It was found that the tetrabutylammonium chloride (TBAC) has the highest catalytic activity in cycloaddition reaction of PMO with p-cyanobenzaldehyde. However, when tetrabutylammonium fluoride (TBAF) was used, the polymerization of PMO was mainly occurred. The stereoselectivity of trans-isomer decreased with increasing of the length of alkyl chaines in symmetric tetraalkylammonium salt. On the contrary, the reaction of PMO with aliphatic aldehyde such as heptanal (HPA)led to aldol condensation of HPA in the presence of TBAB, but cycloaddition reaction did not proceed (Scheme 2).

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2-Iodotoluene[1], 3-iodotoluene [2] J and 4-iodotoluene [3] were sulfonated in 85, 92 or 98% sulfuric acid at different temperatures in the range of 20-120 °Cfor 2 h, and isomer distributions of their sulfonation products were determined by HPLC analysis. The influences of substituent groups on sulfonation and disproportionation were examined on the basis of the data obtained. Sulfonation of [1] J and[3] at room temperature gave[8] and [12], respectively, as major products. At higher temperatures, side reactions such as disproportionation and isomerization via iodine migration became apparent, resulting in the formation of complex, sulfonic acid mixtures which contained di- and triiodotoluenes. In contrast, [2] underwent a selective sulfonation without disproportionation below 80 °C to afford [10] as a main product. At 120°C, however, other isomeric sulfonic acids were obtained appreciably at the expense of [10]. As reference compounds for the HPLC analysis, six isomeric iodotoluenesulfonic acids [8]-[13] were prepared independently by reported procedures.

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Matsugasaki, Sakyo-ku, Kyoto-shi 606 Japan The rates and the activation parameters for the thermal cis-to-trans isomerization of three different groups of thioindigo dyes, 5, 5'-dialkylthioindigo dyes [1], 7, 7'-bis(alkoxycarbonyl)thioindigo dyes [2], and 7, 7'-bis[(2-alkoxyethyl)oxycarbonyl] thioindigo dyes [3] embedded in a smectic mesophase of butyl stearate were determined. The transition of the liquidcrystalline to the isotropic phase affected the reactivity for isomerization of 1 and 2, depending upon the alkyl length. Whereas the mesophase had no influence on the isomerization of 3, irrespective of the alkyl length.

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Colloidal stability formed from trioctanoylglyceride(TriC₈) a nd cholesterol-bearing pullulans (CHP) has been investigated. Pullulans (Mw.30000, 50000, and 137000) were substituted in part by cholesteryl groups, and the substitution degree of the cholesterol moieties was 2-6per hundred glucose units. When TriC₈ was emulsified with a given amount of CHP under sonication, a very stable O/W-emulsion was obtained. The hydrodynamic diameter determined by DLS was approximately 100-200 nm. The particle size of oil droplets was due to the temperature, the duration, and the power of sonication. The higher the substitution degree of cholesterol of CHP employed was, the more stable the emulsion obtained was, and the less the amount of CHP required was to obtain relatively stable emulsion. Similarly, the larger the molecular weight of CHP was, the smaller the particle size was. The O/Wemulsion so obtained was stable enough even in the presence of the Ca²⁺ ion of physiological concentration. Using this technique, a lipophilic antitumor drug, a-linolenic acid (ALA), also was able to be well emulsified by mixing with a suitable amount of TriC₈ in the presence of CHP. These newly developed 0/W-emulsion stabilized by cholesterol-bearing pullulan derivative was promising in making a potent carrier of lipophilic drugs.

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From type I collagen extracted from the lathyritic rat skin with a n eutral salt solution, α₁ theα1 polypeptide chain was separated on CM-cellulose column. The α₁, chain was cleaved by cyanogen bromide, and the peptide supposed to be corresponded to the a1-CB 1 peptide (N-ter minal telopeptide) was isolated. The isolated peptide was found to be incomplete as the α1-CB 1 peptide by amino acid analysis, but contained almost all sequences of N-termina l telopeptide. The obtained peptide was designated as α₁-CB 1'. The CD spectra in UV region revealed that 30% of the α₁-CB 1' peptide was the β-sheet structure and the remainder 70%the random coil state. By measurement of 11-I-NMR spectra in D20 in the temperature range of 5-50°C, the difference of 0.034 ppm for Tyr-α CH chemical shift and the difference of 0.022 ppm for Ala-α CH chemical shift were observed between 5 °C and 50 °C. The intensity of fluorescence of the peptide (excitation at 275 nm and emission at 305 nm) decreased as 34%, whenα1-CB 1' was mixed with CB 6. The intensity of fluorescence did not change, whenα₁-CB 1' was mixed with the CB 7. These results suggest the possibility that this α₁-C B 1'peptide interacts with the CB 6.

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Alginate gel spheres were prepared by pouring an aqueous solution of sodium salt of alginate (NaAlg) into CaC1₂, SrCl₂, and BaC1₂ solutions. The changes of weight and volume of the gel during the gelling process were measured. A rapid dehydration occured initially (1-2h), and slow one was followed (3-4 d). The ratios of equilibrium weights of the gels to those of the original NaAlg drops wg, e/ws, depended on the kinds of electrolytes and showed the minimum (0.4'0.5) about at the concentration of electrolytes C_M=-0.05 mol/dm3. The order of wg.e/ws.o were C a->Sr-=BaAalgn dw erer eversoe f thes electivitioefst hec ounterions and the magnitudes of the elastic moduli. The equilibrium CaAlg gels were analyzed by Flory's theory of swollen network, and interaction parameter x, was found to decrease with increasing the concentration of CaCl₂.

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Calix[n]arene derivatives (n=4, 6 and 8) and alkanoic acids were studied as carriers to examine the passive and competitive transport of alkali metal cations in the chloroform membrane system. Calixarene derivatives did not transport any cation by themselves, except proton ionizable ones, which selectively transported Cs₊ as reported previously. The mixture with alkanoic acid, however, mediated the transport effectively, so that they acted as carriers cooperatively in this system. In the presence of dodecanoic acid almost all the neutral calixarenes transported Li₊ efficiently and selectively.2-Bromododecanoic acid was more effective than dodecanoic acid on the transport rate in all systems. Structural effects on the transport abilities of th e cooperative carriers are discussed on the basis of the results.

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Copolymers of 2, 3-epithiopropyl methacrylate (ETMA)-styrene derivatives were prepared by a solution polymerization in benzene using azobisisobutyronitrile as an initiator and the electron-beam exposure characteristics of these copolymers were investigated. p-Chlorostyrene (pCS), m-chlorostyrene (mCS), and (chloromethyl) styrene (CMS) were used as styrene derivatives. The copolymers with lower molecular weight distribution were obtained by fractionation of bulk copolymers using dissolution-precipitation method. The following resuits on electron-beam exposure characteristics were obtained: electron-beam sensitivity of these copolymers increased with increasing molecular weight and ETMA content. The copolymers with lower molecular weight and lower molecular weight distribution showed higher contrast. The sensitivity of ETMA-pCS copolymers was slightly lower than that of ETMAmCS copolymers, and the order of contrast was reverse to that of sensitivity. However ETMA-CMS copolymers had higher sensitivity than ETMA-pCS and ETMA-mCS, the ETMA-CMS was unstable as electron beam resist. ETMA-pCS 'copolymers had higher dry etching resistance than ETMA homopolymer. ETMA-pCS and ETMA-mCS copolymer showed resolution capacity of O.6 pm and 0.45 pm, respectively.

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The behavior of electrification induced by photopolymerization at the contact interface between photosensitive layer and insulator films was studied with the aim of developing a new recording material and the methord of preparing plastic electrets. The photosensitive system to induce electrification is m ade of a photosensitive layer, comprising a polymer as a binder, an initiator for photopolymerization, a chain-transfer agent and acrylic monomer, which is coated on aluminium plate, and a polymeric insulator film as a contact material is then laminated on the photosensitive layer. Negative or positive charge was induced on the polymerized layer surface by peeling off the cover film after imagewise exposure according to the triboelectric series of the contact films. The negative charge was obtained with the films such as 66 nylon and poly(vinyl alcohol) that tend to be positive charge in the triboelectric series. In contrast with that, the positive charge was obtained with cellulose triacetate or polyethylene film that tends to be negative. The quantity of the charge induced on the layer also depended on the triboelectric series of the films, and on the thickness and the composition of the photosensitive layer. The above and other experimental results suggest that the photoinduced electrification is attributed to the contact tribocharging involving the contraction of the photosensitive layer.

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Environmental behavior study was carried out for alkylbenzenesulfonates (LAS) in Tokyo Bay and main rivers of its drainage basin. LAS represents a mixture of homologues having various alkyl chain lengths with isomers of varying phenyl position. The concentrations of each LAS homologue and 2-phenyl isomer in the environment, the influents and effluents of some sewage treatment plants, and some domestic detergents were analyzed using high performance liquid chromatography with fluorescence detection. The compositions of the LAS found in these samples were different among each sample and reflected biological or physicochemical processes which each LAS component was removed by. (1 ) About 90% of LAS was removed by sewage treatment. A shift toward shorter alk yl chain length in the residual as compared with the original LAS was quite apparent. The selective removal of 2-phenyl isomer during activated sluge treatment process also occurred. ( 2 ) After LAS had been discharged into the rivers, longer rchain, more sorpti ve LAS homologues and 2-phenyl isomer were relatively enriched in the river sediment.2-phenyl isomer was also removed by biodegradation. Thus average LAS chain length was found to be shorter and 2-phenyl isomer ratio to be poor in the river waters. ( 3 ) Longer chain LAS homologues and 2-phenyl isomer w ere abundant in the bay water samples in comparison with the river water samples or the effluent sewage samples. This can be explained by much release of the absorbed LAS from the river sediment and running into the bay as dissolved and suspended LAS by the rise of the rivers in heavy rainfall. Thus chemicals in river sediment may contribute to bay water pollution.

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To develop a new disinfection method for drinking water, estimations of electric current densities and consumed electric powers have been investigated for a practical disinfection electrodialysis system with cation- and anion- exchange membranes under various conditions. Equations of the current densities and consumed electric powers have been derived by applying an equivalent electric circuit equation and a process design equation to the unit cell of the electrodialysis system. The calculated val ues were compared with the experimental values obtained from the practical disinfection experiments using Tama river sample solution added with various amounts of sodium chloride. It was found that the calculated values are almost equal to the experimental ones, i. e., the electric current densities and consumed electric powers necessary for perfect disinfection can be estimated from the equations.

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Hydrous lithium metatitanate (Li₂TiO₂⋅nH₂O) fine particles were formed from the alcoholic solution of lithium and titanium alkoxides. Titanium tetraisopropoxide was added to the butanol or ethanol solution of lithium tert-butoxide, and then the mixed solution was hydrolyzed with H₂0-i-C₂H₂OH solution. In the case of Ti/Li mole ratio=0.5, the sharp XRD profiles of Li₂TiO₃only were observed in the XRD pattern of the precipitate when heattreated at 800°Cfor 1 h. The weight loss of 15% of the precipitate was observed due to dehydration in the temperature range from 100°C to about 800°C, which corresponded to n=1.4 in the chemical formula described above. The remarkable grain growth of the precipita te by the heat-treatment at 800°C for 1 h was recognized in the SEM observation; the wellshaped Li₂TiO₃ particles of about 200 nm in length was obtained.

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