In Penning ionization electron spectroscopy (PIES), the k inetic energy of electrons ejected by collisions between targets. (gas or solid) and metastable atoms is analyzed. In a gas phase spectrum, an outer orbital exposed outside the repulsive molecular surface gives a stronger band than does an inner orbital localized inside the surface. Thus, the relative band intensity of the spectrum depends on the spatial electron distribution of individual molecular orbitals. Using this feature of PIES, stereochemical properties of various molecular orbitals can be studied. Further, the relative band intensity of Penning spectra can be interpreted in terms of calculated exterior electron densities (EED) for individual molecular orbitals. If PIES is employed for the study of the solid surface, ( i ) the outermost surface layer is selectively probed, and ( ii ) the electron distribution of individual orbitals exposed outside the surface can be studied. These characteristics of surface PIES can be applied to observe the changes in the molecular orientation and the electronic state of the outermost surface layer during the epitaxial growth and the amorphous-crystal transition of organic films. The change in the structure of monolayers including LB films, and chemical reactions that take place on the outermost surface layer can be sensitively detected by PIES.

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Oxygenation of cyclohexylbenzene (CHB) was studied in the presence and in the absence of hydrogen bromide.
The oxygen ation without hydrogen bromide was a typical autooxidation producing 1phenylcyclohexyl hydroperoxide (PCP). The selectivity of the hydroperoxide depended mainly on the conversion of CHB, irrespective of the temperature (90-140°C) and the pressure of oxygen. In the chain process hydrogens on secondary carbons were also abstracted. Consequently isomeric hydroperoxides were produced up to 10% of PCP.
On the other hand, the oxygenation in the presence of HBr proceeded below ambient temperature at atmospheric pressure, producing phenol and cyclohexanone directly. A radical chain charactor of the reaction was proved by means of inhibition with benzenediol derivatives, although the reaction itself yielded phenol, a radical inhibitor. HBr played roles of an initiator as well as a mediator producing Br radical which was estimated to be the main species for hydrogen abstraction in this catalytic reaction. The conversion of CHB and quantity of oxygen absorbed depended mainly on the quantity of HBr fed. Between oxygen absorbed and HBr fed a relation 0₂/HBr=3.2 mol/mol was found. When HBr concentration went beyond a critical value, the reaction was hindered. Such a critical phenomenon was interpreted in terms of acid-catalyzed formation of stronger radical scavenger from phenol and cyclohexanone.

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A new method (chelate method) was developed to synthesize a ceramic material, Ba(Ma_1/3Ta_2/3)0₃ (BMT), by use of an organic chelating reagent, 8-quinolinol. A solution containing magnesium and tantalum ions was added to an aqueous ammonia solution of 8-quinolinol to make a precipitate of chelate. This precipitate was thermally decomposed and mixed with an equimolar amount of barium carbonate. The mixture was fired at elevated temperatures, resulting in BMT. Evaporation of the Mg-8-quinolinol chelate took place when the precipitate of chelate was simply fired at 1100°C. This evaporation problem was solved by heat pretreatment at 250°C for 6 hours prior to the firing at 1100°C. When the solid state reaction took place among three elementary components: barium carbonate, magnesium oxide and tantalum oxide, an intermediate product, BaTa₂0₆, was formed during the firing process. Single phase BMT was not obtained even when the mixture involving the above three components was fired at 1300°C for 1 h. By the chelate method, on the contrary, single phase BMT was formed directly without any intermediates at the same firing conditions. The formation of a single compound, viz. MgTa₂0₆, containing both magnesium and tantalum is preferable before the reaction with barium carbonate in order to produce BMT without formation of any intermediates.

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Four diastereoisomers were successfully isolated as the crystals from four eluates (E I, E II, E VIII and E IX) of eight separated ones. The elemental analyses indicated that the crystals have the compositions of [Co(adao)(L-pro)]C1O₄·mNaC1O₄·nH₂O {(m, n) = (0, 1.5), (O.5, 2.5), (0, 1) and (0, 0)}, respectively. Their absorption spectra showed that the respective crystals obtained from E I and E II were trans(Ο) isomers, and the crystals from E VIII and E IX were cis(Ο) isomers. As shown in Fig.1, it is apparent that adao in the trans(Ο) isomers coordinates with the β-mer(N) coordination mode. From the circular dichroism (CD) spectra, the configurational effective CD curves and the vicinal CD curves of L-pro in the isomers were calculated. On the basis of the configurational CD curve for the trans(Ο) isomer from E I, it has been deduced that the isomer has the Δ(ΔΔΔΛ)-β-mer(N)-trans(Ο) structure. Therefore, the isomer from E II has been assigned to the Λ(ΛΛΛΔ)-β-mer(N)-trans(Ο) one. Because the configurational CD curve of the cis(Ο) isomer from E VIII is similar to the observed CD curve of the known Λ(ΛΛΛΔ)-β-mer-(N)-cis(Ο)-[Co(adao) (gly)]C104, the isomer from E VIII is considered to have the Λ(ΛΛΛΔ)-β-mer(N)-cis(Ο) structure. Similarly, the isomer from E IX has been assigned to the Δ(ΔΔΔΛ)-β-mer(N)-cis(Ο) one.

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On thermal decomposition of copper(II) hydrogen salicylate tetrahydrate Cu(Hsal)₂·4H₂O(sal=C₆H₄OHCOO)[1], an anhydrous monomer, Cu(Hsal)₂ [2] and a dimer Cu₂(Hsal)₄ [3] were obtained at water vapor pressures under 26.0mmHg and above 143 mmHg, respectivery. In the case of dehydration of copper(II) benzoate trihydrate Cu(C₆H₅COO)₂·3H₂0 [4], an anhydrous dimer [6] was prepared at water vapor pressures under 143 mmHg on the other hand, a new anhydrous complex [7], which is different from [6] was obtained above 273mmHg. Moreover, an amorphous anhydrous complex [5] was obtained at approximately 0mmHg.
For both copper(II) hydrogen salicylate and copper(II) benzoate complexes, different anhydrous complexes were formed at various water vapor pressures. The fact suggests that a gaseous phase-solid phase reaction plays an important role.

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The ion-exchange behavior of hexavalent uranium (UO₂²⁺) complexes with chloride ions was studied by use of a strong anion-exchange resin. The average charge of uranyl complexes adsorbed by the resin was correlated with their standard reduction potential strength for ion exchange which indicates their adsorbability. The values of the average charge and potential strength were determined graphically from the single intersection of correlation curves drawn for varying uranium concentrations. The effects of temperature and liquid-phase concentration of chloride ions on the average charge of adsorbed uranyl complexes were examined in this manner. As a result, several species of uranyl complex ions, including higher-order complexes bearing more than five chlorine atoms, were strongly suggested to coexist on the anion-exchange resin. This finding is noteworthy because these higher-order complex ions are known to be unstable in aqueous solutions due to their steric hindrance and have never been observed either in solutions or on anion-exchange resins. The conventional graphical method for determining the coordination number of adsorbed metal complex ions was reviewed and compared with the present method. The latter provided a drawing of isotherm curves which fitted better the experimental resuls over a rather wide range of uranium concentrations.

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The concentration of tin and copper distributed in the sediments of Bay area have been studied by atomic absorption spectrometry (AAS). About 5 g of a bottom sediment was taken and gently heated in a mixture of hydrochloric and nitric acid (3: 1). After decomposition, the resultant solution was filtered off through Toyo-5 B filter paper and diluted to 100 rn/with 1 mol. dm^-3 hydrochloric acid. The contents of tin and copper were determined by the standard addition method. The atomic absorption of tin was measured by air-hydrogen fuelrich flame at 224.6 nm, while copper was measured by conventional air-acetylene fuel-lean flame at 324.7 nm. From this work, it was found that copper contents increased from inlet to recess of the Bay, but tin was distributed uniformly in the bottom sediment. The tin and copper concentration in the bottom sediment at Kamisaki Bay, Mie Prefecture were estimated to be 6.7-15.3 μg/g (dry weight) and 1.6-40.0 μg/g (dry weight), respectively.

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We have previously reported on the removal of interference of coexisting anions and the increase of sensitivity by the addition of carbon black into sample solutions in FAAS. The effect of carbon black on the absorbance of alkaline earth metals and their ionization in airacetylene flame was studied by using atom resonance lines and ion resonance lines as analytical wavelength in this paper. Observed absorbance by using ion resonance lines enabled us to determine many elements in high concentration solutions (except for beryllium). It was found that the absorbance of both lines was increased by the addition of 0.08 w/v%carbon black, the effect on the ion resonance lines being less than that on the atom resonance lines. Since the ionization of alkaline earth metals in the flame was considered to decrease by the burning of carbon black, the effect was supposed to occur as the result of an efficient thermal dissociation on the surface of carbon black particles. Alkali metals such as caesium suppressed the ionization of alkaline earth metals in the flame. Stronger interaction was considered to occur between caesium and carbon black, since the synergistic effect was found about 3.7 times on magnesium absorbance by the addition of 0.08 w/v % carbon black and 1000 ppm caesium.

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Macroporous gel beads for high-speed gel permeation chromatography applicable-to aqueous macromolecules having a molecular weight higher than 10⁶, were prepared with glucomannan from Amorphophalus konjac. The gel beads were prepared by sphering of glucomannan triacetate by means of a suspension and evaporation method, followed by saponification and crosslinking with epichlorohydrin. The gel beads prepared in the absence of a diluent in the process of sphering were microporous and the value of the exclusion molecular weight (for poly(oxyethylene)) was less than 10³.
The exclusion molecular weight increased remarkably by the presence of a diluent such as decahydronaphthalene, tetrahydronaphthalene, and methyl dodecanoate: for example, it was 2 x 10⁶ and over 4.5 x 10⁶ in the presence of 200 and 300 wt% of decahydronaphthalerte based on glucomannan triacetatte, respectively.
These microporous and macroporous gel beads exhibit almost no hydrophobic and ionic interactions with sample substances, yet showed high flow-rate-resisting property. These favorable properties are attributable to the molecular structure of glucomannan and a lower swelling degree of glucomannan gel.

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The decomposition of t-butyl phenylperacetate (BPA) was carried out at 60°C in nine monosubstituted benzenes [1] and seven normal alkanes [2] and the first order decomposition rate constants (k_d) were obtained over the range of BPA concentrations from 1.00 x 10^-3 to 5.00 x 10^-2 mol/l.
The k_d increased as the polarity of the solvent increased and was related to the polarity parameter, E_T; the k_d in benzonitrile was 2.5 times as large as that in tetradecane and the correlation between log k_d and E_T was observed not only for the decomposition of BPA but also for the decompositions of other five initiators. On plotting the k_d in the corresponding solvents of two decompositions, the linear relationship was obtained, respectively. It has been found that the change of k_d for each decomposition depends mainly upon the solvent polarity and the solvent effects on k_d are similar to each other.
In addition, for the k_d in nonpolar solvent [2], the stra ight line with a positive slope was observed between the k_d and the reciprocal of viscosity, 1/η, and also by use of Pryor's equation on viscosity dependence. However, the straight line was not observed for the k_d in [1] and 1/η. It has been also found that the change of k_d in [2] depends on the solvent viscosity.

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Macromolecular complexes (MC) consisting of three materials “polyaluminium chloride”, and iron(III) hydroxide sulfate (PFS) with potassium poly(vinyl sulfate) (PVSK) (PAC) and/or sodium dextran sulfate (DS) and/or sodium tetraphosphate (TPP) and/or sodium metaphosphate (PMP) have been prepared and their properties and structures were studied, focusing the change of conformation for the structure of DS and PVSK and the change of structure for various complexes produced in PAC, and PFS solution according to the experimental conditions. The MC prepared differed from one another in properties and structure.
The MC membrane composed of PAC, PFS as inorganic cationic ma cromolecule and PVSK as an organic polyanion was stable in acidic and alkaline solutions.
The transport ratio of Na⁺, selectivity of K⁺ and Na⁺, and electric potential difference between left and right sides of membrane were measured. As the results, the transport ratio was very high when the electric potential difference was large and maintained for a long time and the methanol solution was used instead of aqueous solution in right side cell. An increase of selectivity was observed in methanol solution of both side cells, but little difference in selective transport of K⁺ and Na⁺ was observed in aqueous solution of both side cells and methanol solution in another side of cell. Methanol as a solvent played an important role in an increase of transport ratio and selective through MC membrane.
It was revealed that functional appearence of active and selective transport of alkali metal ions depended on the physical and chemical factors in the MC membrane. The MC, MC membrane were compared with that constituted of glycol chitosan and PVSK as macromolecules for the difference of characteristics.

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The thermal analysis of copolymers of acrylonitrile with allyl chloride (AC) and α-chloroacrylonitrile (CAN) (the mole fractions of AC and CAN units being 0.035) was carried out in order to clarify the effect of hydrogen chloride on thermal degradation of polyacrylonitrile (PAN). It was recognized from TG and DTA curves that pure PAN gives a very sharp transition accompanied with polymerization of cyano groups at ca.260°C but PAN-CAN and PAN-AC are subjected to a violent pyrolysis at ca. 280 and 300°C, respectively. The degrees of dehydrochlorination from AC and CAN units were determined by IR analysis. During heating process the dehydrochlorination was approximately completed at ca. 225°C in PAN-CAN but proceeded mainly at 250-275°C in PAN-AC. It proved from the relation between dehydrochlorination and polymerization of cyano groups that hydrogen chloride accelerates and retards the latter reaction below and above the temperature at which pure PAN begins to be subjected to a sharp transition respectively. Such effect was explained to be attributable to the action of chlorine atom which was formed by the reaction of thermally degraded polymer radical with hydrogen chloride.

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As one of the application studies on the separation with ceramic membrane, this paperreports on separation of glucose from starch sacc'harified solution with ceramic membrane.In order to increase the rejection of an enzyme, a ceramic membrane was coated by zirconiumcompound to make a dynamic membrane. It was found that the optimum rejection wasobtained at more than 0.95 at 0.27 m/s for feed velocity and at more than 1kg/cm² for the gauge piessure with thedynamic membrane made from 0.05 mol/dm3 ZrOCl₂. The saccharificationof corn starch and the separation of glucose were carried out at 55°C continuously with the conditions described above. Three dm³ of starch suspension contain 270g of glucoseand 1g of gltircoamylase in water. The volume of starch suspension in the feed tank waskept constant by adding newly prepared starch suspension without the enzyme.
The following results were obtaind :(i) The concentration of glucose permeated increasedwith lapse of time up to 15h, and then reached almost constant for 15-40h. (ii) Meanwhile, the enzyme activity decreased gradually but slightly. (iii) The rejection of the enzymemaintained at more than 0.9.
It was concluded that the hydrous zirconium(IV) oxide-dynamic membrane on ceramicmembrane was able to be applied to the separation of glucose from starch saccharified by theenzyme which was not immobilized.

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10-Methyl-9-(p-substituted phenyl)-9, 10-dihydroacridines were synthesized by the condensation reaction of 10-methylacridones with substituted benzenes: with anilines in POCl₃, with Grignard reagents or with phenyllithium.
The visible spectra of the synthesized 9, 10-dihydroacridines were observed in acetic acid to investigate the effect of substituents X and Y on the 9, 10-dihydroacridine moiety and the pendant phenyl group, respectively. Their excitation energy were calculated by the PPPMO method. A little shift. of λmax was observed for the compounds with a relatively low electrondonating substituent Y, 'while a remarkable shift of λmax observed for the compounds with a strong electron-doniting ubstituent Y=NMe₂. The calculated π elecitron density changes by the PPPMO method may support an inteamolecular charge-tiansfer charactor of the first absorption band in which electron densities transfered from ring C (with substituent Y=H, OCH₃, and NME₂) to acridine rings A, B, and D (with no substituent); and from ring A (with substituent X=NMe₂) to the rings B, C and D (with substituent and OCH₃).

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Benzo[1, 2, 3-kl: 4, 5, 6-k'l']bisthioxanthene [1b] was synthesized by the cyclization of 1, 5bis(phenylthio)anthraquinone, which was prepared from benzenethiol and 1, 5-dichloroanthraquinone. The photooxidation of the above red compound [1b] with visible light of 541 nm, gave the colorless endoperoxide [2b]. The photochemical and thermal properties of the endoperoxide [2b] to give [1b] were also investigated.

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The oxidation of 1, 8- and 4, 5-dialkyl-substituted isoquinolines: 1, 8-dimethylisoquinoline [1], 1, 4, 5, 8-tetramethylisoquinOline [2], 1, 4, 6, 8-tetraMethylisoquinoline [3], and 5, 6dihydro-4H-benz[de]isoquinoline [4] with manganese dioxide and with selenium dioxide was investigated.
On the oxidation with manganese dioxide, 1, 8-dimethylisoquinolines [1] gave 1-hydroxy8-isoquinolinecarboxylic acid [5a] and 8-methyl-1-isoquinolinol [5b], so that the 1-isoquinolinol [5b] was assumed to be the intermediate product of the acid [5a]. However, the oxidation of [4] with manganese dioxide gave 1, 8-naphthalenedicarboximide [6] through dehydrogenation.
On the oxidation with selenium dioxide, it was observed that 1-methyl group of isoquinoline was oxidized to aldehyde selectively. Consequently, [1], [2], and [3] gave 8methyl-1-isoquinolinecarbalde [7], 4, 5, 8-trjmethyl-1-isoquilninoecarbaldehyd [8], and 4, 6, 8-trimethyl-1-isoquinolinecarbaldehyde [9], respectively, but [4] was not o xidized.

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Polycondensed fused polynuclear aromatics (COPNA) resins, which are thermos etting, were successfully prepared by heating the mixtures of naphthalene(N) or its derivatives and 1, 4benzenedimethanol(PXG) as a crosslinking agent with p-toluenesulfonic acid(PTS) catalyst. The derivatives used are 1- and 2-methylnaphthalene (α- and β-MN) and 1- and 2-naphthol (α- and β-HN). Reaction rates and some properties of the resulting resins are discussed on the basis of substituent group and substituent position of naphthalene ring.
The PXG/Aro (naphthalene or derivatives) mixtures (0.75-2.50 in molar ratio) were heated with PTS at 90-180°C in a stream of argon. The reaction rate for preparations of these COPNA resins was dependent on the nature of Aro, the PXG/Aro molar ratio, the amount of catalyst, and a reaction temperature. Under identical conditions, the reaction rate was in the order of β-HN> α-HN>N≥β-MN>α-MN.
The optimum conditions to prepare B stage resins are as follows. For N, β- and α-MN, PXG/Aro; 1.50, PTS; 5wt%, Temperature; 120-130°C, Reaction period; 2-5h. For β-and α-MN, 1.25, 5wt%, 113°C, 1.5-2.5h.
The resulting B stage resins fuse at ca.70-90°C and dissolve into organic solvents such as pyridine and THF. By heating at 120°C for 20h and then at 200-300°C for 1h, they became infusible and insoluble completely. After curing and post-curing, α- and β-HN resins showed serious weight loss at 400°C and the other resin at 500°C in both air and nitrogen. When allowed to stand in air at 200-250°C for 50 h, the weight change was scarcely observed in N, α-MN and α-HN resins, but β-MN and β-HN resins increased their weight through oxidation.

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A simplified and rapid analytical procedure for the determination of lead and cadmium in PVC resin was proposed.
The sample of PVC resin was cut into pieces (ca.2mm × 2mm) and about 50 mg of them was packed in the powder paper as shown in Fig.2. The package was placed in between the platinum basket and platinum coil, and set in the 1000ml oxygen flask as shown in Fig.1. After the air in the flask, the inner wall of which was prewetted with 0.5 mol. dm^-3 nitric acid was replaced with oxygen, the sample was ignited by electricity and subjected to combustion. The flask was cooled in an ice bath. Then 0.5 mol. dm^-3 nitric acid was sprayed into the flask and it was shaken for 3 min. After the solution containing the combustion products was concentrated by heating and made up to the volume, the lead and cadmium were determined by flame atomic absorption spectrometry.
The detection limits of lead and cadmium were 40 and 3.0μg/g, respectively. The variation coefficient was less than 11% as sholwn in Tables 3 and 4. The analytical results obtained by the proposed method were in agreement with those obtained by the dry ashing and the wet ashing methods. Usually 30 min was required to carry out the whole procedure. Additional 30 min was necessary for hard-to-burn samples such as the wire covering tube. The lead and cadmium content in several PVC resins were determined by this method and analytical results were shown in Table 7.

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For the zeolites containing calcium, which are superior catalysts in high temperature MTO conversion, the effect of the time of adding calcium salt during the crystallization process on the physical properties and the catalytic performance was studied. It was found that large amounts of calcium were contained in the zeolite when calcium salt was added before or during the crystallization, while calcium was hardly done after the completion of it. It indicated that there were at least two kinds of modification states of the acid sites with calcium, because calcium contained by the addition of calcium salt before the crystallization was hardly ion-exchanged with potassium ions, while calcium during the crystallization can be done. Further, it was confirmed by methanol conversion that the amounts of calcium contained affected the yields of ethylene and propylene.

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A selective and sensitive method has been developed for the determination of traces of copper (II) in water sample. This method is based on the extraction of copper(II) as the benzoylacetone complex into dichloromethane followed by differential pulse polarography. An aliquot of the aqueous sample solution containing 0.1-1.5 μg Cu(II) is placed into a 100 ml separatory funnel with stopper, and 5.0 ml of 1 mol·dm^-3 acetate buffer (pH 4.6) is added to it. The total volume of the aqueous solution is then made up to 50.0 ml with water. The aqueous solution is shaken with 10.0 ml of dichloromethane containing 0.1 mol·dm^-3 benzoylacetone and 0.1 mol·dm^-3 tetrabutylammonium perchlorate for 5 min. After extraction, an aliquot of the organic phase is taken into a polarographic cell. The differential pulse polarogram is recorded with a modulation amplitude of 50 mV, a scan rate of 5.0 mV/s, a drop-time of 1.0 s. The peak height at -0.31 V vs. Ag/AgCl is directly proportional to the concentration of copper(II) at the ng/ml level. This method has been applied to the determination of copper in the waste water taken at the campus of Fukui University.

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The hydrogenation of cyclohexanone was carried out at 70°C under atmospheric or high pressure (100kg/cm²) of hydrogen over platinum group metal catalysts in the presence of ethylene glycol. Although only hydrogenated product (cyclohexanol) was detected over osmium, iridium and platinum catalysts, the rapid formation of acetal was preferred over ruthenium, rhodium and especially palladium ones under hydrogenation condtitions. It was suggested that hydrogen took part in the acetal formation, and two mechanisms were postulated for acetalization over metal catalysis.

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