The microwave spectra of cis, gauche, gauche-propyl nitrite and its ¹⁵N isotopic species were assigned in a frequency range from 16 to 32 GHz, and the following rotational constants for the around state were determined:
The r₀ structure of this rotational isomer was derived from a least-squares fit of these six rotational constants with reasonably assumed parameters for propyl group as shown in Table 4. The dihedral angles of this gauche-form were calculated to be (CC-ON)=79.9°and (CC-CO) =74.6° from the trans position, respectively.

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The electrochemical characteristics of three kinds of graphite fluoride electrodes ((CF)_n, (C₂ F)_n, and fluorinated active carbon were studied in an aqueous KOH solution. The flatness of the open and closed circuit potentials of (CF)_n electrode was superior to that of the others. However, (C₂F)_n and fluorinated active carbon electrodes showed higher discharge potentials and lower overvoltages than (CF)_n. The XPS spectral data indicated that the graphite fluoride surface was strongly affected by OH^- and a certain amount of K⁺ in the electrolyte was accumulated on the electrode surface during discharge. From the estimation of the polarization resistance and the activation energy of the electrochemical reduction reaction of each graphite fluoride, it can be presumed that the graphite fluoride electrodes differ from one another in the electrode reaction rate but their reaction mechanisms are essentially the same.

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Photovoltaic organic thin films based on a two-layer structure of electropolymerized poly (N-vyinylcarbazole)(PVCz), polypyrrole(PPy) or poly(N-methylpyrrole)(PMPy) and vacu um evaporated rhodamine B (RB) were prepared. Au/PPy/RB/Al sandwich cells show a typical rectifying property at a relatively high bias voltage (±5 V or ±8 V) as shown in Fig.4.
On illumination, the gold electrode always exhibited a positive photopotential with re spect to the aluminum electrode. The best power conversion efficiency η' was obtained under white illumination of I_T =14.0 mWcm-2 for PPy cell: η'= 5.8 x 10^-8%, FF=0.20, Jsc =7.0tiA. cm^-2, and Voc=580 mV. The effect of the direction of illumination on the action spectra of the short circuit photocurrent Jsc given in Fig.5 and 6 suggests that the photoactive region is not the Au/polymer or Al/RB interface but the thin RB layer contacting with polymer.
The photocurrent Jsc and the input light intensity( I ) obey a formula Jsc ∝I^m, where m depends on the nature of polymer as follows: 0.96(PMPy) >0.90(PPy) >O.75(FVCz). The smaller m value for the PVCz cell suggests that recombination and trapping of free carriers during diffusion to electrodes and a high bulk resistivity should reduce the efficiency of the PVCz cell.

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Thin amorphous films of composition Na₂O.xAl₂O₃(5 x 13) were prepared by RF-sputtering1and converted to Na β-alumina by heat treatment. The effects of the sputtering conditions on chemical composition, microtexture, and ionic conductivity of the films were examined. The Na content in the film varied not only with the Na content of the target, but by the surface temperature of the target. In the case of low surface temperature, the atomic ratio of Na to Al in the films was lower than that of the target. The Na deficiency was due to low sputtering yield of Na atoms. However, the Na content in the films increased with the rise in surface temperature of the target. This fact is considered as. a result of thermal evaporation of Na atoms on the target surface. The microtexture of the sputtered films depended on both the RF-power and the gas pressure, and amorphous films of homogeneous texture were obtained at a lower RF-power(50 W) and lower gas pressure(0.53 Pa).
Thin film Na p-alumina of composition Na₂O.6.9 Al₂O₃ obtained by cryst allization of amorphous films exhibited an ionic conductivity of 5.8 x 10^-2 Sicm at 300°C with an activation energy of 0.26 eV the former value is higher than the conductivity of bulk sintered Na β-alumina. This high ionic conductivity, close to that of a single crystal, is due to both the dense microtexture formed, by crystallization of the poreless amorphous films and the preferred orientation of crystallites with the (001) plane parallel to the film surface. The ionic conduction mechanism of an intermediate phase appearing on the amorphous to β-phase transition is discussed in terms of its nonstoichiometry.

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Catalytic activities of three kinds of noble metal catalysts (Rh, Pd and Ru) supported on TiO2 for CO-hydrogenation reaction were studied to find factors which may define their activities. Although the activities of these catalysts at 250°C were found to be in the order of Rh>Ru>Pd, those depended significantly on the reduction temperature: Rh and P d catalysts exhibited higher activities by the reduction at 400°C than those at 200 and 500°C, whereas reduction at 200°C provided the maximum activity for Ru catalyst. Near the reaction temperatures, adsorption amounts of H2 and CO on the catalysts which were reduced at 400°C decreased in the order of Rh>Pd>Ru which was the same for the amount of irreversively adsorbed CO. The order was very different from that of the catalytic activity. The reactivity of irreversibly adsorbed CO with H2 at 200°C observed by using FT-IR revealed. that its conversion rate into CH, decreased in the following order, Rh>Ru>Pd, corresponding to that of catalytic activity. The rate over Rh catalyst was much larger than that of the catalytic reaction, whereas those over Ru and Pd catalysts were similar to those of the latter reactions. Major portion of the irreversibly adsorbed CO on Ru and Pd catalysts were found to be converted into surface carbon, confirming the acceleration effects of H2on the production of the carbon from adsorbed CO. Such carbon- on Ru and Pd catalysts hindered the adsorption of CO. Catalytic activities of these catalysts for the hydrogenation of acetone are not necessarily related to CO-H, reaction. Based on such results, activation abilities for irreversibly adsorbed CO were suggested to be the important factor for the catalytic activity. The poisoning effect of carbon produced on the surface may not be ignored in the catalytic reactions.

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Recently we have found that the zeolites containing calcium (AEZ-Ca) are excellent in the production of light olefins from methanol. An increase in the amount of the strong acid sites by the release of calcium from the weak acid sites during the reaction has been also found to promote the production of B. T. X and coke deposit which is responsible for the deactivation of the catalyst. In this paper, it is examined to extend the catalyst life of AEZ-Ca, by commingling various alkaline earth metal compounds with the zeolite. About 0.3-1.0 g of MgO, CaCO₃, SrCO, and BaCO₃ were commingled with 1 g of AEZ-Ca. Also, silicalite, which has few acid sites, was used as a reference. The accelerated life test was carried out at 600°C and LHSV=4.6h^-1 until dimethyl ether was detected in the effluent gas. As listed in Table 1, the catalyst life of AEZ-Ca was 22 h and the commingling of MgO or silicalite hardly changed the catalyst life. However, the catalyst life of AEZ-Ca commingled with Ca, Sr and Ba carbonates was extended extremely to 75-150 h. This indicates that these alkaline earth metal carbonates are effective for th e extension of the catalyst life.
Next, the changes of th e product distribution, the coke deposit, and the physical properties of Ca, Sr and Ba carbonates-commingled catalysts with the reaction time were studied (Table 2). Moreover, the chemical composition of the catalyst after the reaction followed by the treatment of HC1 solution (Table 3) and the chemical reactivity of silicalite with BaCO₃ (Table 4) were studied. From the results, it was suggested that commingled alka line earth metal ions entered in the pore of the zeolite to modify the acid sites, resulting in the extension of the catalyst life due to depressing the production of B. T. X and coke.

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The adsorption isotherms of ten kinds of adsorbates (mainly dyes) in the liquid phase were measured on nine kinds of the fibrous activated carbons (ACF) which were prepared from the phenolic resin fabric. For comparison, the adsorption on five kinds of the granular activated carbons (ACG) prepared from the coconut shell were also studied. Each of ACF has a sharp pore distribution in the range of diameter less than ca.4 nm. Each of ACG has transitional and macro pores besides micro pores. The dyes are different in their molecular shapes and sizes. The relation between the cr itical pore diameter (dc) and the critical molecular size of adsorbate was studied on the basis of the adsorption amount.
Main results and informations obtained were as foll ows:
( 1 ) The adsorption of dyes in aqueous solutions pro ceeds within the micro pores of ACF and ACG, but does not proceed within the pores larger than ca.20 nm-diameter on ACG.
(2) The critical pore diameter (dc) for the molecular sieving adsorption is determined by a short-axis size of the adsorbate, and the relation between de and the critical shortaxis size (Le) was obtained as dc=-1.74 L.
( 3 ) The design concept for the prep aration of ACF having the required critical pore diameter (dc) for the objective adsorbates was proposed.

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The adsorption isotherms of eight kinds of the polyethylene glycols (PEG: mean molecular weight: 106-9 x 10⁵) in aqueous solution on nine kinds of the fibrous activated carbons (ACF), prepared from the phenolic resin fabric, were measured. For comparison, the adsorption on five kinds of the granular activated carbons (ACG), prepared from the coconut shell, was also studied. Each of ACF has the mono dispersed pore distribution in the range of diameter less than ca.4 nm. Each of ACG has transitional and macro pores besides micro pores.
The relations betw een the molecular weight of PEG and the critical pore diameter (do)for the molecular sieving adsorption were studied on the basis of the equilibrium adsorption amount. Main results and informations obtained were as follows:
( 1 ) The adsorption of PEG on ACF and ACG proce eds only within the micro pore whose diameter is smaller than ca.4 nm, but the adsorption does not proceed in the transitional pore and macro pore of ACG. The adsorption state of PEG appears to be a solid crystal of, the straight chain-helical structure.
( 2 ) The critical molecular size (Le) of PEG to be adsorbed was found to be controlled by a short-axis size, and was determined to be ca.0.4 nm. Also, de was determined to be ca.1.8 nm.

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Catalytic hydrogenation of olefin is affected by the properties of metal surface. In this research, the hydrogenation of propylene in the presence of supported nickel metal was carried out in the range of temperature (215--252°C) and of the concentrations (C³H⁶: 0.7O-8.2 mol/m³, H²: 3.9--36 mol/m³).
The support materials of the catalysts were silica, titania, niobium oxide, and tantalum oxide. Some of these materials are interesting because it is well-known that the catalytic activity of metal dispersed on the supports changes remarkably with the pretreatment temperature.
The properties of the catalysts were analyzed based on the kinetic measurement of the reaction and on the measurement of the amount of hydrogen irreversibly adsorbed.
For the kinetic study a flow-type micro reactor was used and the l oaded amount of the catalyst was so small as to keep the differential reaction conditions. The adsorption amount of hydrogen on each catalyst was measured by the so-called pulse-flow method.
The observed catalytic reaction rate based on one gram of catalyst changed w ith support materials and with pretreatment conditions. However, the initial rate was found to be proportional to the adsorption amount of hydrogen of the catalyst independent of the change of support and of the pretreatment temperatures. It was proved that this, proportionality is established in a wide range of reaction conditions.

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The variation in crystal shapes of calcium sulfite hemihydrate (sulfite) and a-calcium sulfate hemihydrate (α-hemihydrate), and the crystal growth of α-hemihydrate during the oxidation of the sulfite suspended in water at 125°C- and at 2 kg/cm² in pressure were studied.
Addition of sulfuric acid, to the slurries gave platelike calcium sulfate dihydrate (dihydrate), which was formed on the- surface of spherical sulfite crystals at room tepperature. When temperature was raised from room terriperature to 125°C, both spherical sulfite and platelike dihydrate crystals were obtained in the slurries. As the oxidation proceeded at 125°C, the platelike dihydrate rapidly disappeared, and then needlelike or radial α-hemihydrate crystals grew gradually. It depends on the degree of supersaturation of the solution whether needlelike crystals grew predominantly or not.

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Studies were made on the calcination reaction, constitution, and solubility of potassium silicate fertilizer manufactured by calcination of fly ash from coal at 800-950°C with potassium carbonate and magnesium hydroxide. The fertilizer has been recently developed in Japan as a slow-release potassium fertilizer; it normally contains about 22% K₂O and 3% MgO. The citric solubility of K₂O ranges from 70 to 98% according to the calcination conditions and the type of fly ash (Fig.1).
The fly ash consists of fine glassy par ticles (1-60 pm) containing SiO₂, Al₂O₃, CaO and Fe₂O₈ and crystalline minerals such as mullite 3 Al₂O₃. 2SiO₂ and quartz SiO₂. Duri ng the calcination, potassium diffused into the glassy particles, while calcium in the particles moved to the surface (Photo.3, Fig.7). The glass phase was thus destroyed, forming mainly K₂OAl₂O₃2 SiO₂. Mullite partly reacted to form K₂O. Al₂O₃. Magnesium hardly diffused into the particles and formed K₂0MgOSi0₂ and 2 CaO. MgO₂ SiO₂, reacting with potassium, quartz and calcium. Those compounds are soluble in 2% citric acid.
A portion of potassium formed insoluble glass and K₂O.MgO₃ SiO₂. With th e ash rich in CaO, the total of K₂O and CaO was almost sufficient to form soluble compounds. With CaO-lean ash, insoluble compounds were formed because SiO₂ and Al₂O₃ were in exc ess. The solubility was increased from 80 to 93% with the CaO-lean fly ash by increasing the K₂O content from 22 to 30%.

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Fine metal particles (Ag, Pd and Ag-Pd alloy) were prepared by spray-pyrolysis technique from metal nitrate solutions. The aqueous solutions of metal nitrate were sprayed into the flames (H₂-O₂, H₂-air or H₂-air-N₂) formed by a cylindrical coaxial burner. The shapes and sizes of particles produced differed with the particle formation processes, which could be divided into three depending on the flame temperature. When the flame temperature was lower than the melting point of the metal under consideration, the metal particles were nonspherical (process 1). When the flame temperature was sufficiently above the mp of the metal, particles were formed via the melt and became perfectly spherical (process 2). When the flame temperature was extremely high, the metal evaporated in the flame and ultrafine metal particles (average diameter <0.1-4.2 μm) were produced from the metal vapor with nucleation and growth (process, 3). In processes 1 and 2, the particle sizes were determined mainly by the concentration of the spraying solution (average diameter of Pd particles were 0.5-0.8 μm for concentration of solutions of 0.01-0.1 mol⋅dm^-3). In process 3, the particle sizes were determined mainly by the feeding rate of metal nitrate. In the preparation of alloy particles, the composition in the particles produced by process 2 was identical with that of the spraying solution. In the formation of alloy particles, the contribution of process 3 made the composition in alloy particles non-uniform. When the particle concentration in gas phase was high, the collisions between the particles had a significant effect upon the shapes and sizes of the particles.

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Understanding how property of coal is affected by solvent is of importance to prepare a fuel of coal-water mixture, coal-oil mixture, and to liquefy coal. In order to clarify interaction between coal and solvent, the heats of wetting, swelling ratios, and apparent specific gravities of coals with various carbon contents have been investigated in polar solvents, nonpolar solvents, or polar solvent/nonpolar solvent mixtures. Yallourn, Tenpoku, Taiheiyo, Miike, and Hongei coals were used as coals with various carbon contents. Following results were obtained:
1) The heats of wetting, swe lling ratio, and apparent specific gravity were larger for methanol than for other solvents examined.
2) The heas of wetting and swelling ratio decreased with increasing number of carbon atoms in alcohols.
3) Addition of small amounts of methanol resulted in increasing the swelling ratio of low rank coal in nonpolar solvents.

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The direct characterization of potassium polyphosphate was carried out in conjunction with fractionation by gel filtration and molecular weight measurements. By using TOY0PEARL gel, the time for the fractionation was shortened by 1/3 compared with the case by agarose gel.
The chrom atograms of low molecular weight samples of potassium polyphosphate showed two peaks. Various experiments, such as the measurements of specific refractive index increments of the fractionated solutions and fractionation of the raw materials of potassium polyphosphate and potassium dihydrogenphosphate, were made in order to study the phenomenon. The results indicated that this phenomenon was related to the heating time in condensation polymerization. The light scattering and viscosity measurements were carried out for each f the fractionated solutions. The relationship between the molecular weight, M, and the intrinsic viscosity, [η], of potassium polyphosphate in a saline solution (0.1mol/l) was found to be [η] = 4.94 × 10^-5M^0.80 at 25°C in the raige of moleculawr weight from 1.9 × 10⁴ to 96.1 × 10⁴.

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Polymerization of various vinyl monomers was carried out by use of inorganic materials, such as silica gel, hydroxyapatite, silicon nitride, and silicon carbide, activated by plasma exposure. Argon gas or aqueous vapor was used as an active plasma generator. The silica gel exposed to an aqueous plasma can rapidly polymerize methyl methacrylate and styrene, while an argon plasma exposure was not so remarkably effective for polymerization. The polymerization rate of methyl methacrylate and styrene in benzene solution was dependent on both the monomer concentration to the three halves order and the amount of the silica gel to the one half order. Further, the monomer reactivity. ratio for the copolymerization of methyl methacrylate (M₁) with styrene (M₂) by the silica gel exposed to an aqueous plasma is r₁=O.55 and r₂= O.56. These results suggest the formation of initiation radicals by the transfer of electron trapped on the surface of inorganic material to the monomer adsorbed on the surface.

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Macromolecular complexes (MC) composed of inorganic and/or organic macromolecules were prepared by mixing iron(III) hydroxide sulfate (PFS) with potassium poly(vinyl sulfate)(PVSK), sodium tetrapolyphosphate (TPP), or sodium metaphosphate (PMP), by mixing [2-(diethylamino)ethyl]dextran hydrochloride (EA) with TPP or PMP, and by mixing “polyaluminium chloride” (PAC) with PVSK, TPP or PMP. Their properties and structures have also been studied.
The MCs prepared from inorganic and inorganic macromolecules were less soluble than those from inorganic and organic macromolecules.
The MCs prepared from the TPP-EA and PMP-EA systems at pH 1.0 were formed in orthophosphate with EA, and those prepared at pH other than 1.0 were formed in tetrapolyphosphate and metaphosphate with EA.
The chemical structure of MC prepa red from the PFS and PAC system could not be determined because of various types of structures proposed by numerous investigators.
Phase diagrams of the three-component system NaBr/acetone/H₂O were obtained for MCs composed of PFS with PVSK, PMP with EA, and TPP with EA in inorganic and organic systems, but those for MCs from the inorganic and inorganic systems were not obtained.
The MCs consisting of PFS and PVSK were cast into stable and stronger membrane in acidic and alkaline solutions from 1, 4-dioxane-HCl solution. However, stable and stronger membrane in other systems could not be obtained because it was brittle and soluble in water. The transport ratio was high when the membrane potential difference was larger and maintained for a long time in the HCl-NaCl system. In addition, the active and selective transport were also measured when that poly(styrenesulfonate) ion of large ion size was used as a counter ion. It was revealed that the functional appearence of the active and selective transport of alkali metal ions depended only on the physical factor of the MC membrane without but not on the chemical factor.

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A new Langmuir-Blodgett (LB) through has been constructed having the same width as a solid substrate. It has two moving walls which can move together with the float on the water surface during compression and deposition. Since a monolayer moves wi th the moving walls, there exists no friction between the monolayer edge and the wall.
In the case of ordinary LB trough, which width is much wider than that o f solid substrate, the monolayer is compressed unhomogeneously between the center and edges of the trough. Upon its deposition, the monolayer moves irregularly around the substrate because of shear force. Therefore, the films deposited on the substrate have different molecular assembly from that on the water surface.
Using the new LB trough we could succes sfully prepare good LB films of trivalent metal (lanthanum and aluminium) stearates, which are well-known for not forming LB films by means of the ordinary LB trough. Sharp and higher X-ray diffraction patterns were obtained from those multilayer assembly films having highly ordered structures.

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The particulate and gaseous matter sampling was carried out at Institute for Nature Study, National Science Museum in Tokyo during June 11-22, 1985, and February 4-9, 1986, in order to investigate the behavior of ammonium chloride and ammonium nitrate in the atmosphere. Gaseous HCl and NH₃ were collected by Na₂CO₃ and H₃PO₄ impregnated filters in series, after the removal of particulate matter containing ammonium chloride and ammonium nitrate with Teflon filter. The diffusion denuders were used for the collection of gaseous HNO₃. Each component was extracted with distilled water from the collected samples and its amount was determined by ion chromatography. The average concentrations of gaseous NH₃, HCl and HNO₃ over more than 100 measurements were O.18, 0.026, and 0.006 μmol/m³ in summer period, and O.09, O.008 and 0.004 μmol/m³ in winter period, respectively. On the other hand, the average concentrations of particulate ammonium, chloride and nitrate were O.13, O.04 and 0.07 μmol/m³ in summer period, and 0.015, 0.09 and 0.03 μmol/m³ in winter period, respectively. The concentration ratios NH₃/(NH₃+NH₄⁺), HCl/(HCl+Cl_-) and HNO₃/(HNO₃+NO₃^-) were higher in summer period than those in winter period, and a correlation between these ratios and temperature was observed. Furthermore, a strong correlation between the measured concentration products ([NH₃] [HCl] and [NH₃] [HNO₃]) and reciprocal temperature (1/T) was observed. These results could be explained by the following dissociation equilibria,
NH₄Cl( s )_??_NH₃(g)+HCL(g) and NH₄NO₃(s)_??_NH₃+HNO₃(g).

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Extraction and removal of mecury from an anaerobic sludge was studied. The sludge was obtained from a sedimentation tank of laboratory wastewater treatment plant. Mercury in the sludge could be extracted by aerating the sludge suspension under the presence of KI. To remove the extracted mercury, the supernatant solution in aeration tank was circulated via either anion-exchange resin or activated carbon column (Fig.1, Table 2). Anion-exchange resin was more effective for the removal of mercury than activated carbon; the mercury content in the sludge decreased from 125 to 10.4mg⋅kg^-1 in the presence of O.1 mol⋅dm^-3 KI (Method I ). In this case, about 91% of mercury in 560g of anaerobic sludge could be concentrated in 10cm³ resin (Table 4). Extraction of mercury with KI could be done more effectively when the anaerobic sludge was converted to aerobic one prior to the addition of KI (Method II). In this case, the mercury content in the sludge decreased to 1.6-3.7 mg⋅kg^-1. Extraction of mercury by 0.02 mol⋅dm^-3 KI was also possible and the mercury content of 6.0 mgkg-1 was obtained (Table 5). About 86% of cadmium in the sludge could be removed with O.1 mol⋅dm^-3 KI, but other heavy metals such as copper, zinc and lead were scarcely extracted (Method I ). When the extraction was done in the presence of 0.1mol⋅dm^-3 KI plus 0.01mol⋅dm^-3 EDTA (Method II), over 90% of metals were released. But these metals could not be removed by anion-exchange resin under the presence of EDTA (Table 6). These results indicated that this method was effective and specific for the removal of mercury from an anaerobic sludge.

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The effect of reducing powders (metal hydrides, sulfur and carbon black) were. zompared and scrutinized on the flame atomic absorption spectrometry of magnesium, which shows the highest degree of enhancement by the addition of reducing powders among alkaline earth metals. Measurement was carried out after dispersing these reducing powders by ultrasonic agitator in sample solution that contained 0.05 μg/ml of magnesium in water, N, N-dimethylfolmamide (DMF) or dimethyl sulfoxide (DMSO). Absorbance increased about 2.5 times for DMSO solution with the addition of O.08 w/v% calcium hydride and about 1.2 times for DMF, compared with the absence of the reducing powder. Synergistic effect of organic solvents was also observed.

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