Surface Enhanced Raman Scattering (SERS) spectra were measured for 1, 10-phenanthroline, 4, 7dipheny1-1, 10-phenanthroline (batho-phenanthroline), 2, 9-dimethy1-1, 10-phenanthroline (neo-cuproine)and 2, 9-dimethy1-4, 7-dipheny1-1, 10-phenanthroline (batho-cuproine) adsorbed on an electrochemically roughened silver electrode surface. The spectra showed an evident SERS effect and potential dependence. From comparison of the SERS spectra in detail, possible geometries of those molecules on the silver surface were deduced. It turned out that the phenanthroline molecular planes are more or less tilted on the silver electrode surface.

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This paper reports a unified apparatus for measuring transient properties of phosphorescence emission by using a pulsed lighting Xe lamp and a high-speed analog-to-digital converter (ADC) board for personal computers (PC). The apparatus has the advantages of high flexibility and easy construction.
Xe lamp of pulsed operation was adopted for excitation light source. Photoelectric signa ls were converted by means of a high-speed ADC board and were stored on the memory of PC against time axis. Thus phosphorescence decay curves were directly obtained. The phosphorescence intensity at a certain wavelength was obtained by the full summation of decay data on the memory, such that the short-lived emission components corresponding to excitation light pulse were excluded. Phosphorescence spectra were obtained by scanning the observation wavelength and phosphorescence excitation spectra by scanning the excitation wavelength. Time-resolved phosphorescence spectra were also obtained by a selected summation of decay data on a limited time range.
The performance of the apparatus was tested by the measurements of standard samples and the system was found to have satisfactory performance.

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Concerning to the solution to obtain alumina precursor fiber, i. e., (1) NCS solution: A1 (OPrⁱ)₃A1 (NO₃)₃citric acid H₂O system (A1 (OPrⁱ) ₃ mol/A1 (NO₃) ₃ mol =2, H₂O mol/total Al mol = 50, total Al mol/citric acid mol = 10), and (2) NS solution: A1 ( OPrⁱ)₃Al( NO₃) ₃ H₂Os ystem (A1 ( OPrⁱ)₃ mol/A1 (NO₃) ₃ mol = 2, H₂Omol/total A1 mol = 50), it was investigated how the addition of citric acid affected the solution structure by small angle X-ray scattering measurement (SAXS). Crystallization kinetics of aalumina by heating of the gel specimens obtained from these solutions was investigated using quantitative X-ray diffraction (QXRD) measurement. The radius of gyration (Rg) obtained from SAXS measurement decreased accompanying concentration from as-prepared solution to spinnable one in both NCS and NS solutions. The Rg of former solution was 50 Å, and latter's was 100 Å in the concentrated spinnable solution. The structure change of A1 clusters in the solution accompanying concentration was affected with or without addition of citric acid even if the molar ratio of Al (OPrⁱ) ₃ to A1 (NO₃) ₃ was the same in both solutions. It was shown by QXRD measurement that NCS specimen had shorter incubation period than NS specimen in isothermal heat-treatment at 950, 1000°C and 1050°C. Activation energy of NCS specimen obtained from the Arrhenius plot of 1/ T(absolute temperature) and rate constant obtained from Avrami equation were slightly larger than those of NS specimen. These phenomena were considered to be caused by the differences in structure of dried gel specimens, which reflected the differences of carbon quantity andthat of cluster structure in solutions resulting from withor withoutthe addition of citric acid. The Avrami exponents were 1.6 in both specimens. The differences in structure of specimens, which is supposed to reflect the difference in solution structures between with or without citric acid, does not affected the nucleation and growth mode.

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9-Bromo-5, 6-dihydro-4H-benz[de] isoquinoline (2a) was obtained by the reaction of 5, 6-dihydro4H-benz[de]isoquinoline (1) with N-bromosuccinimide (NBS) in concentrated sulfuric acid. Further reaction of 2a with NBS gave 7, 9-dibromo subustituted product (2b). Similarly, 9-bromo subustituted product (5b) was produced by the reaction of 1-chloro-5, 6-dihydro-4H-benz[de] isoquinol ine (4) with NBS in concentrated sulfuric acid.
Chlorination of 9-bromo-5, 6- dihydro-4H-benz[de]isoquinoline N-oxide(3a) gave a mixture of 3chloro and 1-chloro substituted products (5a and 5b). Further, 4 was obtained by the reaction of Noxide of 1 with phosphoryl chloride.

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Oxidation of acylferrocenes was carried out in some alcohols in the presence of trichloroacetic acid. The reaction took different course from a normal oxidation reaction observed in alkylferrocenes. The reaction is considered to consist of two steps. In the first step, carbocation was formed by a proton addition to carbonyl group followed by cleavage of cyclopentadienyl ring-iron bond. In the second step, Fe³⁺ ion formed through oxidation of Fe²⁺ ion attacks other ferrocene molecules. The reaction rate of both steps are markely influenced by solvents and substituents and discussed in terms of steric and electronic effects.

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lα, 25-Dihydroxyvitamin D₄ (22, 23-dihydro-lα, 25-dihydroxyvitamin D₂) (1) and D₇ (24-epi22, 23-dihydro-1α, 25-dihydroxyvitamin D2) (3) were synthesized via 25-hydroxyvitamin D₄ (18a) and D₇ (18b) respectively. Condensation of phenylsulfonyl derivatives (6a, b) with 22-iodo derivative (13)obtained from ergosterol followed by deprotection of hydroxyl groups and reductive desulfonylation of coupling product (14a, b) and elimination of the protecting group of ergost-6-ene nucleus on 15a, b afforded 5, 7-diene (16a, b). Irradiation of 16a, b and thermal isomerzation of 25-hydroxyprevitamin D₄(17a) and D₇ (17b) gave 18a and 18b. Conversion of 18a, b into 25-hydroxycyclovitamin D₄ (19a) and D₇ (19b), allylic oxidation of 19a, b, acetolysis of 1-hydroxycyclovitamin D₄ (20a) and D₇ (Mb), and removal of protecting groups of hydroxyl groups of acetolysis product (21a, b) produced 1 and 3. laHydroxyvitamin D₄ (2) and D₇ (4) were prepared via vitamin D₄ (18c) and D₇ (18d).

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A thermosensitive hydrogel prepared from poly (N-isopropylacrylamide) (P (NIPAAm) ) forms a nonpermeable dense surface layer around the gel when it was immersed abruptly in an aqueous solution at a higher temperature than its phase transition temperature 33.5°C. Thus, some matters entrapped in the gel cannot diffuse through the layer into the outer solution at higher temperatures than the transition temperature, but can do at lower temperatures. Then we investigated the applicability of the a denosine 5'-triphosphate (ATP)-entrapped P (NIPAAm) gel (ATP-Gel) to control of pH of the solution containing Zn²⁺ by fluctuating of the outer solution between the two temperatures above and below the transition temperature. ATP was selected as a diffusate from the gel in consideration of some application to the Drug Delivery System (DDS). On immersing the ATP-Gel in the Zn²⁺-containing solution, the release of ATP from the ATP-Gel was confirmed by an increase in UV absorption based on the adenine ring of the ATP molecule and a simultaneous decrease in pH of the solution was observed due to the release of H⁺ with the formation of ATP-Zn^2-C binary complex. In case of the abrupt immersion of the ATP-Gel in the solution at 40°C, the pH of the solution remained almost constant, indicating the depression of the release of ATP from the ATP-Gel. It was able to regulate the decrease and constancy in the pH of the Zn²⁺-containing solution repeatedly by the alternate immersion of the ATP-Gel in the solution between 25°C and 40°C. Further, an ATP-Gel with an increased degree of crosslinking showed a more gradual decrease in the pH of the solution at 25°C.

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Chelating resins containing mercapto groups (RES) were developed by the functionalization of macroreticular 2, 3-epithiopropyl methacrylate-divinylbenzene copolymer beads (RE) with alcoholic potassiurn hydrogensulfide. The resins RES with different pore structures were derived from a series of RE prepared by changing the compositions of ternary mixtures consisting of the two monomers and 2-ethylhexyl alcohol as diluent (porogen) in suspension copolymerization. Behavior of RES in adsorption and elution of noble metals was studied. The uptake ofthese metals is strongly influenced by crosslinking densities and specific surface areas (pore structures) of RES. The RES with the highest capacities for the metals can be derived from the highly porous RE prepared by using 10 mol% of divinylbenzene and 100vol% of the diluent per the monomeric mixture. The increasing order in the metal uptake by the RES is as follows: Pt (IV)∼Ir(IV)<Pd (II)<Os (VIII)<A u (III) T he adsorbed Au(III), Pd (II) and Pt (IV) on the RES were effectively and rapidly eluted with 0.1-0.2 mol dm^-3 aqueous potassium cyanide solutions, whereas the elution of the adsorbed Os (VIII) and Ir (IV) with the eluents was extremely difficult to achieve.

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Adsorption behavior of poly (vinyl alcohol) (PVA) containing silanol groups (silanol-modified PVA)to inorganic substances in aqueous solutions was investigated. In the cases of Shokozan clay, calsium silicate and alumina, the amounts of adsorbed PVA increased with increase in the content of silanol groups in PVA, and viscosity increase or gellaion in aqueous slurries was observed. Properties of composites consisting of inorganic particles and a small amount of silanol-modified PVA was investigated. Water absorption of dried sheets made from larger particles and silanol-modified PVA was smaller than those from smaller particle systems. In the former case, penetration of water into voids among the patricles was much smaller, while in the latter case there were ten times more water compared with the volume of voids. Water permeation to the sand layer, on the surface of which silanol-modified PVA aqueous solution were spread, became remarkably smaller. The water permeation constant was much smaller by 10^-4 cm s ^-1 than that of clay which is known to be the smallest value in sands. Adhesion strengths of silanol-modified PVA films to glass plates and alumina plates were markedly larger compared with the ordinary PVA systems. These results were thought to arise from the reactions between silanol groups in PVA and silicon hydroxide and aluminum hydroxide in the surfaces of inorganic particles.

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Measurements were made of the adsorption of trichloroethylene (TCE), tetrachloroethylene (PCE)and o-chlorophenol (OCP) by activated carbon from aqueous solutions, and of the regeneration by supercritical or liquid carbon dioxide. Intraparticle diffusion coefficient was determined to be 3.33×10^-9 cm²s at 20°C for the adsorption of TCE. The activated carbons loaded with these chloro compounds w e/re regenerated by supercritical carbon dioxide at 35°C and 200 kg/cm². The easiness of the regeneration was TCE > PCE > OCP. The regenerated fraction did not depend on pressure so much in case of OCP loaded activated carbon by the extraction with liquid carbon dioxide. Supercritical carbon dioxide is thus better than liquid carbon dioxide for recycling of carbon dioxide after separation and recovery of OCP from carbon dioxide.

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Polychlorobiphenyl (PCB) has been considered harmful substance. In order to dispose of it, burning method is generally investigated. However, to give rich energy to a harmful substance may produce another harmful substance. Considering this circumstance, a low energy detour from a poison to a harmless substance is needed. In the present work, 2.7 g of PCB, 2.0 g of powdered silica gel, 6.3 g of Ti (OC₄H₉)₄, and 500 ml of tetrahydrofuran were mixed in a flat-top beaker while being illuminated by filt ered visible light of fluorescent lamps. The reaction was continued for 1 week at room temperature and 4.9 g of glass-like solid product was obtained. Ninety three per cent of PCB had disappeared and could not be extracted, by methanol, from the solid product. IR and reflectance spectra studies of the substance thus obtained indicated that the product was a copolymer of Ti (OC₄H₉)₄ and PCB from which chlorine atoms have been removed.

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Effects of poly (vinyl alcohol) (PVA) as a binder on pressed compacts of alumina powder were investigated from the viewpoints of bending strengths, bending moduli and densities of green bodies. With increasing water contents in granules at press molding, the strengths and moduli increased. This shows the importance of the decrease in glass transition temperature (Tg) of PVA owing to absorbed water to a temperature below the press molding temperature. PVA should be plasticized well at press molding, but should not contain a lot of plasticizer after molding to enhance the strengths.
Several PVAs modified with comonomers were studied as a binder. PVA copolymerized with a small amounts of VeoVa (vinyl ester of C₁₀ carboxylic acid) and itaconic acid was found to be a good binder showing the marked increase in the green strength and density. Effects of the contents of the two comonomers were investigated in more detail. The PVA system with the most suitable composition revealed 3 times stronger in bending strength and 4 times larger in toughness compared with the ordinary PVA system. This is thought to arise from the lubricating effect of long parafinic chains in the comonomer moiety to afford the deformation and compaction of the granules.

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The electric contact at the sliding part of small power motors, which are used at relativery low voltages and small currents, often encounters serious problems of so called “black powder” formation. The problems have been settled successfully by using certain vapor lubricants developed by our group. This paper deals with the mechanism of how and why the vapor lubricants give rise to (an) excellent performance. The following conclusions have been obtained mainly on the base of ¹⁴Ctracere xperiments. (1)When certain organic compound, such as ethylene glycol, is present in the surrounding atmosphere of motors, it adsorbs preferentially onto the surfaces of sliding parts, commutators and blushes, and forms a lubrication film through some mechanochemical reactions. Mass spectrometry indicated that the film is consisted of at least nonvolatile dimeric materials. (2) Frictional motion of commutator provides renewal of its surface to promote the formation of lubricant film. (3) Once the contact surface is covered by the lubricant film, the adsorption of undesirable aromatic compounds is inhibited and the black powder formation is prevented.

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In order to obtain an imaging diagnostic agent which adsorbs selectively to atheroma, three kinds of [tetrakis (phosphonooxyphenyl)porphyrinato]manganese (III) were synthesized. Namely, they ar e manganese (III) complexes of 5, 10, 15, 20-tetrakis [4- (phosphonooxy) phenyl]porphyrin [Mn (tPPPm)5, 10, 15, 20-tetrakis [3, 4-bis (phosphonooxy) phenyl] porphyrin [Mn (OPPd) 1, and 5, 10, 15, 20 -tetrakis [3, 4, 5-tris (phosphonooxy)phenyl]PorPhYrin [Mn(tPPPt)] (Fig.1). Among these, [Mn(tPPPd)] adsorbed well to calcium carbonate (rate of adsorption: 48%) and [Mn(tppt)]adsorbed well to deoxycholic acid (rate of adsorption: 54%).

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Treatment of azulene (1) with 0.2% formaldehyde in acetic acid under nitrogen at 25°C for 1 h gave five products: Namely, 1, 1'-methylenebisazulene (2), 1, 3-bis (1-azulenylmethyl) azulene (3), 1, 1'-methylenebis [3- (1-azulenylmethyl) azulene] (4), 1, 3-bis [3- (1-azulenylmethyl) -1-azulenylmethyl]azulene (5), and 1, r-methylenebis[ [3- (1-azulenylmethyl)-1-azulenylmethyl]azulene] (6). The structures of the products were established on the basis of their spectroscopic (UV-vis., MS, and 1H-NMR) data.

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It was examimed to improve the catalytic activity of octasodium (2, 3, 9, 10, 16, 17, 23, 24octasulfonatophthalocyaninato)cobaltate (II) (CoPc) for decomposing acetaldehyde which is one of the factors of cigarette smell. By the impregnation of water-soluble polymers into CoPc-containing filter paper used as a deodorant filter, the author was able to raise the decomposition efficiency of acetaldehyde (η)from 16% to 74%. It was also found that η of the deodorant filter is inversely proportional to the equilibrium constant K for complex formation between CoPc and impregnated water-soluble polymer. The each value of K was calculated from Hildebrand's equation of the difference spectra between CoPc plus water-soluble polymer and CoPc only.

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