The measurement of specific surface area of sample powder was studied by means of the flow method using various sample tubes of cylindrical and horizontal types. The apparatus of gas chromatograph was modified and used. The powder used for measurements was alumina (Al₂0₃, 200 mesh) and the adsorbed gas was nitrogen (N₂). The adsorbed temperat ure is 196 °C(liq. N₂). Helium was used as carrier gas and diluent and the flow rate was 30 m//min. The surface area was calculated according to the general procedure of the BET method.
In the case of the tube of horizontal type, the specific surface area was determined to be constant only when the amount of sample was within a range from about 20% to 40% of the tube, while, in the case of the tube of cylindrical type, it was obtained as constant value when the amount exceeds 40% of tube volume. Since it was confirmed that specific surface area was determined to be constant by the static method using a sample tube of cylindrical type whithin a range O.2 to 10.0 g. It was concluded that the specific surface area deter-, mined by the flow method is influenced by the packing fraction of sample in the sample tube.

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In order to reveal the reactivity of monosubstituted benzylamines, we observed the hydrogen isotope exchange reaction (liquid-solid reaction) between benzylamine (or one of monosubstitued benzylamines) dissolved in p-xylene and poly(vinyl alcohol) labeled with tritium at 70 °C. The rate constants for these materials have been obtained with the A"-McKay plot method. Comparing these rate constants (and the rate constants obtained previously)with each other, the followings have been clarified. ( 1) The reactivity of benzylamine can be enhanced with one of the substituents (which have the electron-attractive effect) since the reaction constant (ρ) for monosubstituted benzylamine in the reaction is greater than zero (p=1.6). ( 2 ) The degree of I-effect (or R-effect) of a certain substituent bonded to benzylamine can be expressed quantitatively when the effect of the substituent on the reactivity of CH2I\TH2 group is investigated with the rate constants. ( 3 ) It is fairly certain that the reactivity of monosubstituted benzylamines in the reaction follows the Hammett rule (not the Taft's equation). Accordingly, monosubstituted benzylamines may be regarded as aromatic compounds. ( 4 ) Comparing the reactivity of several compounds with each other using the rate constants obtained previously leads to the following equality: phenol: benzylamine: aniline: benzaldehyde =12: 6.6: 1 3 1.0

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The oxidation process of porous nickel plaques in molten alkali carbonates with different'compositions at 923 K has been studied by using the thermogravimetric analysis under various gas compositions. It was shown that the oxidation process consists of two stages with different oxidation rates. The rate of the first oxidation stage is very close to the rate of gas phase oxidation, and that of the second oxidation stage, which appears immediately after the first oxidation stage, is constant to the final oxidation state of lithiated NiO, depending on O₂partial pressures and Li/K composition ratios. The second stage was attributed to the real process during the in situ oxidation of porous nickel impregnated with carbonate melts, and its rate was discussed in terms of the local cell oxidation of nickel by dissolved oxygen in the melt. It was concluded that the oxidation process is controlled by O₂- and CO₂ mixed diffusion through a thin melt film on nickel particles.

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New solid-state enzyme sensors capable of potentiometric or amperomet ric detection of glucose were explored based on the proton-conductive thick-film of antimonic acid spin coated on a porous alumina substrate. Two types of planar sensor element were fabricated by depositing the sensing electrode (Pt), counter electrode (Au) and/or reference electrode (Ag) on top of the proton-conductive film by RF sputtering (Figs.1 and 2). Glucose oxidase (GOD)was applied on the Pt electrode together with a carbon paste which not only immobilized GOD but also protected the proton-conductive film from deterioration in the phosphate buffer solution (Fig.4), while the remaining surface was covered with a water-proof coating layer. The two-electrode type element attached with a pair of sensing and counter electrodes worked as a potentiometric sensor which varied emf logarithmically with a change in the concentration of dissolved 02, H₂O₂, and glucose (5 x 10^-4-4 x 10^-2M) in the phosphate buffer solution (Figs.5 and 6). The Nernst's slope (-54 mV/decade) for glucose coincided perfectly with that for H202, indicating that the response to glucose is generated through its enzymatic reaction product, H₂0₂. The sensitivity to glucose was fairly stable for 10 days (Fig.7). The same element could be used as an amperometric sensor when the sensing Pt electrode was polarized vs. an external Saturated Calomel Electrode (SCE) (Fig.8), and the electrolytic current at the fixed polarization of O.7 V (vs. SCE) was well correlated with the glucose concentration (Fig.9). This finding facilitated the design of three-electrode type element by incorporating an internal reference Ag electrode which was inactive to H₂O₂ (Fig.10). The electrolytic current of this element increased as the Pt electrode was polarized vs. the Ag electrode (Figs.11 snf 12), and the amperometric response at the polarization of 0.7 V was linear to the concentrations of H202 and glucose (0-7 x 10^-3M) (Fig.13), with the rather rapid response rates (Fig.14). It was further shown that the short-circuit current of the two-electrode type element could also be utilized for the amperometric detection of dissolved 02, H₂O₂, and glucose (0-4x 10^-3M) in the buffer solution (Figs.15, 16, and 17).

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Various AI₂O₂-supported iridium catalysts for the decomposition of hydrazine were prepared by using the thermostable alumina synthesized by an improved sol gel method. The thermal stability of the catalysts was evaluated by comparison of the catalytic activities before and after thermal treatments at high temperatures (750-850°C) in an inert gas atmosphere. It was found that the performances of the Ir/Al203 catalysts using the thermostable alumina were better than those of the Ir/Al₂O₃ catalysts using commercial alumina. The performances and the deterioration of the Ir/Al₂O₃ catalysts strongly depended on the solvents used at the Ir impregnation step: C₂H5OH was better suited for the catalyst preparation than CH₃CN and H₂O. C₂H₅OH solvent gave finer dispersion of iridium on the catalysts after aging than CH3CN. XPS analyses showed that C₂H₅OH tended to have a larger amount of iridium deposited on the surface region of catalysts than H₂O.

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By using the instantaneous mixing method, silica alumina co-gels with different compositions were prepared from aqueous solutions of sodium silicate and aluminium nitrate. The Al203 compositions of the co-gels were found to be correlated with the compositions of the solutions by a relation similar to that of a vapor-liquid equilibrium. This suggests that the escaping tendency of each chemical species in the solution influences the composition of the solid deposit as similarly observed in the case of liquid condensation from vapor phase. Although the specific surface areas and the primary particle diameters of the co-gels went through a minimum and a maximum, respectively, at an alumina content of 50 mass%, both the amounts of solid acid and the catalytic activities for the isomerization of 1-butene went through maxima at two alumina contents of 20 and 70 mass%. The two maxima in the solid acid amount can be predicted based on a surface arrangement model.

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The liquid-phase hydrogenation of crotonaldehyde has been investigated with silver-manganese mixed oxide catalyst. Relationships between activity, 2-buten-1-ol selectivity and crystal states of catalysts calcined at different temperatures were examined. The catalyst calcined at 500 °C had a high conversion of 85.1% and 2-buten-1-ol selectivity of 71.8%. The catalyst was prepared from a mixed solution of silver nitrate and manganese nitrate and an aqueous solution of sodium hydroxide by coprecipitation method. The active catalyst is mainly composed of amorphous Ag₂O, amorphous MnO_, and a crystalline γ-Mn₂O₃. The effects of manganese oxide in the catalyst are to inhibit the reduction of amorphous silver oxide to silver crystal at low temperature, and to cause an increase in the concentration of active silver in the catalyst surface, which probably lead to a high activity and a high selectivity of the catalyst.

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The self-supporting disk surfaces of Cs and/or Re-doped silver powders (500 ppm of each element referred to Ag) were measured by XPS, in order to investigate the electric charges of Cs, Re, and 0, their surface concentrations, and their dynamical behaviors during the operation of O₂-Jet in ultra high vacuum system (UHV).
On the single element-doped silver samples, the binding energies (BE) of Cs 3 d 512a nd Re 4 f_7/2 were 723.9 and 45.7 ev, respectively, after being oxidized by oxygen, whereas they. shifted to 725.6 and 40.8 eV, respectively, after being kept under the most reducing conditions (heating at 483 K in UHV). On the (Cs+Re)-doped sample, BE of Cs 3 d_5/2was 0.2-0.7 eV lower than those on Cs-doped one under every condition, and the lowest value, 724.4eV, was obtained after being oxidized by oxygen; the highest BE, 46.5 eV, of Re 4 fv, was observed during the operation of O₂-Jet at 483 K, but the spectrum at around 45.7 eV indicated above was not detected under any condition. The Re 4 f_7/2, spectra at 46.5, 45.7, and 40.8eV were assigned to Re₇₊, Re₆₊, and Re_O, respectively, whereas the Cs 3 d_5/2 spectrum at 725.6 eV would result from Cs0., species (x<1/2) and the spectrum at 723.9 eV did from CsO₂.0 1 s spectra had large full width at half maximum (FWHM) and could be deconvoluted into four or five core spectra (FWHM-1.7 eV) by curve-fitting method. The spectrum at the lowest BE (528.4-529.0 eV), assignable to oxydic oxygen, was observed only with the (Cs+Re)-doped sample oxidized at 483 K. Surface atomic compositions varied depending on the sample conditions. For the Cs- or Re-doped sample, compositions of Cs, Re, and 0 were in the ranges of 1.0, 3.3, 0-0.4, and 7.6 -27 atom%, respectively, while those for the (Cs+Re)-doped sample were 3.2-7.2, 0-1.1, and 30-38 atom%, respectively. It was noted that the 0 composition was far larger in the last sample. Especially conspicuous responce to Or. Jet were exhibited by the (Cs +Re)-doped sample heated at 483 K; with increasing exposure time, Re 4 f_7/2 spectrum rapidly shifted from 40.8 to 46.5 eV and Cs 3 d_5/2 did from 725.4 to 724.6 eV, whereas 0 1 s gradually did to the low BE side. The O 1 s core spectrum at 528.7eV increased up to 18% of the total area ofO 1 s specrum. From these results, it was estimated that the simultaneous addition of Cs and Re enhanced the sorption of oxygen, increasing the amount of the oxygen species of lower BE, as well as facilitating to keep the Re7+ state and the Cs state surrounded by a large number of oxygen atom.

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The influences of oxygen contents on the structural parameters and superconducting properties of Pb-doped Bi-Sr-Ca-Cu-O samples (2223 and 2212 phases) were examined. Temperatureprogrammed-desorption (TPD) measurements revealed that sorption and desorption of small amounts of oxygen (2-3 x10^-5 mol/g) took place reversibly for both samples below 600 °C (Figs.3, 8). The lattice parameter along c axis and the structural modulation period along b axis in each sample were found to increase as oxygen content decrease and vice versa (Figs.5, 7). These reversible changes in structural parameters could be explained to r esult from the desorption and sorption of excess oxygen in Bi-O layer. The dependence of T, on the oxygen content for the 2223 sample was quite different from that for the 2212 sample, i. e., with decreasing the oxygen content T_, of the former decreased by 15 K from 111 K to 96 K, while the latter increased (Figs.4, 9). These results suggest that for both samples T_, is related with the hole concentration in Cu0₂ plane which is controlled by oxygen co ntent.

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Intercalation of monoalkylamines and aniline into layered aluminium dihydrogentriphosphate dihydrate, A1112133010H.2 0 (abbreviated to ADHP), was examined by using powder X-ray diffraction method, DTA-TG, and IR spectroscopy. A linear relationship was recognized b e tween carbon numbers of alkylamines and the interlayer spacings of intercalation compounds. The slope of the straight line was 2.1, sugge s ting the formation of bilayers such that alkylamines are intercalated into ADHP lay e r at a tilting angle 563. The interlayer spacing (d=7.9A) of ADHP was extended to 18.8A. by intercalation of aniline. When the facility of intercalation of alkylamines into ADHP w a s compared, alkylamines of relatively large carbon numbers such as octyl-(C8) and decylam i ne (C, o) were intercalated more readily into ADHP than those of small carbon number s (C1--C4)or of carbon numbers above C, 2. When intercalation compou n d s of methyl-, ethyl-, and propylamine were treated with 0.1moldm-3 phosphoric acid, these alkylamines in interlayer were removed to give the origin al ADHP. However, intercalation compounds of alkylamines of carbon numbers above C 6 and aniline showed stronger water-repellency and floated on water surface. Results of DTA a nd TG revealed that alkylamines and aniline were held firmly between ADHP layers and thu s, were stable at above their boiling points. Alkylamines intercalated in ADHP began to de c ompose at around 350°C.

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A laser irradiation nuclear magnetic resonance (NMR) instrument has been developed for the purpose of measuring high resolution NMR spectra under the irradiation of a laser. The laser irradiation was carried out from the bottom of a sample tube passing through the inside of temperature controller. This instrument first enable us to observe NMR paramagnetic shifts and paramagnetic relaxations resulted from the photo-excitation of diamagnetic metal ions. In this paper, the photo-induced effects on the ligand exchange reactions of various uranium(M)(uranyl) complexes were studied. In bis(acetylacetonato) (dimethyl sulf oxide)uranyl complex, the rate of intramolecular exchange reaction of acetylacetonato ligands was accelerated by the laser irradiation. The remarkable photo-induced effect was observed for the oxygen 17 NMR measurements. On the other hand, no photo-effect was observed in the associative fluoride exchage reactions of fluoro uranyl(V) complexes with fluoride in the bulk.

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A novel chemiluminescent(CL) method for the determination of hydrogen peroxide was developed. The method was based on a fluorescein (FL)-CL reaction catalyzed by horseradish peroxidase at pH 7. O. Effect of four buffer components, citrate, phosphate, imidazole and 2-morpholino-l-propanesulfonic acid (MOPS) on the determination was tested. Citrat e, phosphate and imdazole yielded higher CL intensities than MOPS. Citrate gave a lower detection limit of H₂O₂ than MOPS by a factor of 2.5. Citrate and phosphate were superior to MOPS and imidazole in view of masking transition metal ions which interfered with the determination. A combination of MOPS with EDTA was also effective for precluding the interference from the metal ions.
The CL emission was attribu table to the formation of an excited FL dianion in comparison with the fluorescent and CL spectra of FL. Singlet oxygen also played an impotant role in the formation of the dianion, which was deduced by testing the reactivity of several quenchers and enhancers for active oxygens. Thus, the mechanism of the CL reaction was proposed, in which FL serves dual functions of producing singlet oxygen and of being an energy acceptor from singlet oxygen.

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Characteristics of sodium ion-selective electrodes (Na-ISEs) with polymeric membranes incorporating cyclic and acyclic compounds as ionophores were studied and their applicability to analysis of physiological fluids was examined. In this study, bis[(12-crown-4)methyl]methyl(dodecyl)malonate [bis(12-crown-4)] and polyether-amide com pounds (ETH 157, ETH 2120) were used as ionophores and adipic esters [bis(2-ethylhexyl) adipate, bis(1-butylpentyl)adipate] were used as plasticizers. These Na-ISEs showed Nernstian slope of 54-57 mV/decade and response time of <10 s. Among three ionophores examined, bis(12-crown-4) was the most selective to Na ⁺ in the presence of drugs [1, 1-dimethy1-5-methoxy-3-(di-2-thienylmethylene)piperidinium bromide monohydrate and [2-(α, α-dicyclopentyl acetoxy)ethyl]triethylammonium bromide] and lipophilic quaternary ammonium salts such as a cationic surfactant (trimethyloctadecylammonium salt) as well as cations. The cause of interference to three Na-ISEs by the above two drugs was studied. Then, the migration of interfering substances into the sensing membrane was suggested by the measurement of potential response characteristics. In the analysis of control serum samples, good reproducibility (C. V. =0.3-0.4%) was obtained by all Na-ISEs. But accuracy in the analysis of patient serum samples was varied with the type of ionophore of Na-ISE. The deviation of error (S_yx) was as follows,
ETH 157>ETH 2120>bis(12-crown-4)
Therefore, Na-ISE based on bis(12-cro wn-4) was applied to the analysis of serum, plasma and urine samples. Good correlation was obtained between the results of this Na-ISE and flame photometry. From the point of stability of Na-ISE and accuracy in the analysis of physiological fluids, it was suggested that the Na-ISE based on bis(12-crown-4) as an ionophore would be useful in the field of clinical analysis.

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Synthesis of high quality quartz glass was accomplished by the thermal decomposition of a quaternary ammonium silicate about 1000 °C. Quaternary ammonium silicate was prepared at room temperature in a Yield of 65% by adding 1 mol quaternary ammonium salt to a 0.5 m ol/1 of sodium metasilicate aqueous solution, with adjusting pH to 11.8 by the addition of 0.01 mol HC1.
It was con sidered that the reaction proceeds according to the following expressions ( 1 ) and ( 2 ).
Na₂SiO₃ + 2[(CH₃)₄N]Cl_??_ [(CH₃)₄N]₂SiO₃+2 NaCl ( 1 )
[(CH₃)₄N]₂SiO₃+31/2O₂_??_ SiO₂ +8CO₂+2NO₂ + 12H₂O( 2 )

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The azo coupling reaction of p-dimethylaminobenzenediazonium tetrafluoroborate with mphenylenediamine has been investigated in a water-1, 2-dichloroethane two-phase system. It has been found that, among the organic acids examined, dipicrylamine and thiols such as pentachlorobenzenethiol and 2, 4-dinitrobenzenethiol acted as efficient anionic phase-transfer catalysts.

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We succeeded to solubilizing 4-dicyanomethylene-2-methyl-6-(p-dimeth ylaminostyryl)-4 Hpyran (DCM) in poly(N-vinylpyrrolidone) (PVP) aqueous solution, but its fluoresent intensity one hundredth decreased.
From the equi librium constant between DCM and PVP, it was assumed that the interaction between DCM and PVP is due to the hydrogen bond between NH, group of DCM and C=0 group of PVP.
The mechanica l properties and fluorescent wavelength of the film which was casted from the system of DCM-PVP aqueous solution differed from the film which was casted from the system of DCM-PVP DMSO solution.

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The sorption amount into soil of atmospheric alkanes and alkenes of carbon number 3 to 10 was measured to elucidate the relation of sorption amount to carbon number of hydrocarbons. The Henry's law was possible to be used for showing sorption amount of these hydrocarbons. Henry's law constant became larger with the increase of carbon number, and the relation of Kh to N was shown by equation log Kh=0.53 N-3.33 (r=0.99) for alkanes and log Kh=0.62 N-3.75 (r=0.99) for alkenes. Kh is the Henry's law constant and N is the carbon number.

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Single crystals of [Sr₂Cu₂O₃]x15[CuO₂] (x= 0.696) were successfully obtained using KC1 as a flux. This compound takes a composit crystal structure. The first subsystem is [Sr₂Cu₂0₃]and the second one [Cu0₂]. Both subsystems h ave an orthorhombic structure with superspace group mArs The compound has mutually incommensurate periods along the c axis. The lattice prameters are a= 11.457( 5 )Å, b=13.409( 9 ) Å, c1= 3.935( 3 ) Å, c2= 2.740 ( 2 ) Å. Characteristic features of this compound are chains and sheets composed of Cu and O atoms.

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