Oxygen reduction activities of gas-diffusion type carbon electrodes loaded with perovskitetype oxides La_i-xCa_xM0₃ (M =Co, Mn, x=0-0.8) were examined in 30 wt% KOH at 25°C. Among the electrodes tested, the highest electrode performance, i. e.3.0 Afcm2 at-125 mV vs. Hg/HgO, was marked with large surface area La_0.6Ca_0.4CoO₃ (17 m²/g) prepared by an amorphous precursor method (Fig.4).
Kinetic analysis based on Rotating Ring Disk Electrode methods showed that Co-containing systems were highly active for both the 4-electron O₂ reduction and the HO₂- decomposition, while Mn-containing systems were highly active only for the former (Table 1). The electrochemical and catalytic activities increased greatly with increasing the specific surface area of the oxides (Table 1, Figs.3 and 4). It was deduced that the electrode performance at low overvoltage (low current density) was determined mainly by the 4-electron O₂ reduction activity of the electrode catalysts while that at high overvoltage (high current density) was by the HO₂- decomposition activity (Figs.7nd 8).

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The synthetic conditions were investigated for preparing the high-T_c (2223) phase of BiPb-Sr-Ca-Cu-O superconductor. TheLhigh-T_c phase could be synthesized with good reproducibility from a mixed solution of nitrates of constituent metals, by evaporation, calcination, and sintering, the optimum temperatures of which were found to be 350°C, 820°C (12 h), and 845°C (60 h), respectively (Figs.1, 3, 4, 5). Mixing of the solution at the evaporation as well as the repetition of the calcination were also important for obtaining the high-T_c phase (Figs.2, 8). As suggested from XRD analysis, the low-Tc (2212) phase was first produced at the calcination stage (820°C) and then changed into the high-T_c phase at the sintering stage (845°C) (Figs.3, 4, 8). It was also suggested that the (2223) phase could be derived more easily, as the (2212) phase was produced in a purer and better grown form at the calcining stage (Figs.8, 9, 10). Pressing and re-sintering of the obtained (2223) phase increased the packing and orientation of planer crystals (Figs.11, 12).

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Synthetic fluorohectorite was pillared with alumina in the presence of poly(vinyl alcohol)(PVA). The interlayer distance, nitrogen adsorption isotherm, and the amount of a lumina were compared with those pillared with alumina in the absence of PVA. The int erlayer distance was 24Å for pillaring in the presence of PVA in contrast to 8.4 Å for pil laring in the absence of PVA. The more pronounced expansion of the interlayer distance sugges t s - that the pillars are three times longer in the former fluorohectorite than the latter. In accordance with the expansion observed, the amount of alumina was three times larger f o r pillaring in the presence of PVA than in its absence, i. e., 0.3 0 g ig-clay vs.0.1 1 g ig-cla y. A BET equation satisfied the nitrogen adsorption isotherm for pillaring in the pre sence of PVA, while a Langmuir equation did for pillaring in the absence of PVA. The order of mixing was found to be important for expansion of the interlayer distance of the alumina pillared fluorohectorite: first PVA was added to fluorohectorite and then cationic o ligomers of hydroxoaluminum, the precursor of alumina pillars, was added dropwise to the mixture. The role of PVA was discussed on the basis of the effect of the concentration of PVA on the expansion of the interlayer distance.

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Tris[1-(p-substituted phenyl)-1, 3-butanedionato] manganese(III) complexes, MnL₃ (L =p-XC₆H₄COCHCOCH₃, X=NO₂ 1, COOH 2, COOCH₃ 3, Br 4, Cl 5, H 6, NHCOCH₈ 7, C₂H₅ 8, CH₈ 9, OCH₃ 10, OH 11), have been synthesized, and their configuration and sta bility were investigated by magnetic and spectral measurements.2, 7 and 11 obtained as hydrate were heated to g ive anhydride at ca.110←C under a reduced pressure. The anhydrous complexes of 1-11 have the high spin octahedral structure of d4configuration in solid state and as well as in chloroform, pyridine and DMSO. As the absorption bands due to v_co+v_oo, Ring dif. + v _Mn-O + v_O-OH3, and ⁵A_Ig-← ⁵B_1g transition, which were related to the bond between carbonyl oxygen and manganese (III), shifted to the higher frequency side with the increase of electron donation of the substituents, the strength of Mn(III)-O bond and the stability of these complexes were found to increase in the order of 1<2<3<4<5<6=7<8<9<10<11. The ligand field band of ⁵A_1g← ⁵B_1g, transition shifted slightly to the higher frequency side with the increase of polarity of the solvent used

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The complexing equilibria of oxovanadium(IV) ion with the multidentate ligands, 7-(3, 5dihalo-2-pyridylazo)-8-hydroxyquinoline-5-sulfonic acid (diX-PAHQS, X=. C1, Br), which are expected to coordinate to oxovanadium(IV) ion either with N, N, O-(N-atom in pyridine ring, N-atom of adjacent one in azo group to quinolinol ring, O-atom of quinolinolate)terdentate sites or with N, O-bidentate moiety of the quinolinol, have been investigated both spectrophotometrically and polarographically focusing on the coordination selectivity of the chelate ring. The variations of the reduction potentials and electronic spectra with cornplexations are studied to see whether the azo group in the ligands participate in the cornplexations or not. The complexing equilibria of these complexes are analyzed and the stability constants of the complexes are calculated. It was found that the azo group in these ligands did not participate in the complexations, namely the complexations occurred by using only the quinolinol moiety to form stable N, O-chelate ring in lower pH ranges. On the contrary, in higher pH ranges the complexes were dissociated by the hydrolyses of the oxovanadium(IV) ion. ESR spectral data supported these results. The coordination modes of oxovanadium(IV) ion with the ligands, 2-(3, 5-d ihalo-2-py r idyl a zo)-1-h ydroxynaphthalen e-4sul f on ic acid (diX-αPANS, X=C1, Br), 1-(3, 5-dihalo-2-pyridylazo)-2-hydroxynaphthalene-6sulfonic acid (diX-βPANS, X=C1, Br) and 7-(4-X-phenylazo)-8-hydroxyquinoline-5-sulfonic acid (BAHQS for X=H and Cl-BAHQS for X=C1), are also studiedto see a role of N-atom in pyridine ring and that in quinolinol moiety.

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Partition electrochromatography (PEC), a new separation method based on the combination of electrophoresis effect with a countercurrent partition technique, is established. PEC is carried out by using rotation Jocular countercurrent chromatography (RLCC) apparatus. Two immiscible liquid phases are put into the separation column (Fig.1). The polar phase serves as the medium for migration by electrophoresis (EP), and another as the chromatographic stationary phase. EP is performed in a horizontal rotating column. When direct current voltage is applied across the column, each electrocharging substance in the column moves with a certain rate depending on its electrophoretic mobility and partition coefficient. Results of fundamental experiments for determining experimental conditions are shown in Table 2. Separation of guinea green B from naphthol yellow S and ponceau SX by the proposed method is much improved as compared with RLCC method based only on the partition effect (Fig.3). Brilliant blue FCF was separated from guinea green B (Fig.4, 5) by migration elution (ME) over 150 h (Fig.2), and elution of the latter which has low mobility is achieved by RLCC continued after electrophoretic separation. All the runs were made at room temperature. The present method performs the continuously migrating elution without supporting medium and may be applied to preparation works and separation of macromolecules and particles.

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A simple and rapid method for the determination of trace amounts of anionic surfactants was proposed. When a sample solution was filtered through a filter paper impregnated with mixed hydroxide of aluminum and zinc, anionic surfactants were collected on the filter/paper as reddish violet products given by the reaction with Rhodamine B. The paper was washed with water to remove excess reagents and extracted with ethyl alcohol. The absorbance of the extract was measured. Interference from iron(11), calcium and phosphate could be avoided by the addition of a small amount of zinc chloride and cation-exchange resin. Dodecylbenzenesulfonate as low as 0.02 ppm could be determined. The method was applied to the river water.

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The dependence of the concentrations of trace elements (Sn, Cu, Zn and Mn) in muscle and organs of cultured yellowtails on the body weight was examined during a 17 month period from May, 1980 to October, 1981. Four elements were analyzed by means of atomic absorption spectrophotometry after wet digestion with a mixture of nitric acid and hydrogen peroxide. The following results were obtained.
( 1 ) In the liver: the concentrat ions of copper and zinc increased gradually with the increase in body weight of up to 1500 g, whereas those of manganese were invariable.
( 2 ) In the muscle: the concentrations of copper, zinc and manganese w ere invariable.
( 3 ) In the kidney: the concentration of zinc increased markedly with the i ncrease in body weight about 2000 g, and reached 61.8 I/μpig for a body weight of 2800 g.
( 4 ) In the pyrolus: the concentrations of copper, zinc and manganese de creased with the increase in body weight about 500 g, and were constant for body weights of up to 1000 g.
( 5 ) In the blood: the concentrations of copper, zinc and manganese were invariable.
( 6 ) The concentration of tin in every organs was lower than 1.0 μpeg. From results obtained, it was suggested that zinc played an importa nt part of the birth of yellowtail and the kidney was controlling the changes in concentration of elements in the organs with the growth of yellowtail. tStudies on the Behavior o f Some Trace Elements in Bay Area. V.

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Swelling experiments for poly(butadiene) (BR, nonpolar rubber ) and poly(acrylonitrilebutadiene)(NBR, polar rubber) in a saturated vapor phase and in solution of mixture of toluene and ethanol have been studied. In this case, toluene is good solvent and alcohol is nonsolvent for these rubbers.
In NBR, the maxim um degree of swelling in the mixture was obtained at a toluene concentration around 90-80%. In BR, no such maximum was obtained. For both samples, absorption of vapor of the mixture was measured by the method of quartz crystal microbajancc. Results showed that the absorption behavior was affected by polar-polar interaction between NBR and ethanol.
From sw ollen rubbers equilibrated for a enough time in saturated vapor phase of the mixture, title absorbed liquid was recovered and its composition of toluene and ethanol was dete rmined. The composition obtained was compared with that of the liquid used for the saturation. There was almost no difference between them as shown in the Table 2. It m eans there may be no difference between in swellimg behaviors of rubbers when contact in the l iquid and stand in its gas phase.

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A surfactant polyion complex film composed of dihexadecyldimethylamm onium and poly (styrenesulfonate) (PIC-I) was prepared by casting method. The effect of water on the bilayer structure in the film was studied by DSC, wide angle X-ray diffraction, ESR, and viscoelastic measurement. The result s of DSC (Fig.1) and X-ray diffraction (Figs.2 and 3) indicate that the growth of the bilayer structure and the lamella structure parallel to the film surface requires the annealing in hot water above the phase transition temperature (Tc) of the bilayer. The structure of the polyion complex film before and after annealing was schematically shown in Fig.7. Wi th increasing temperature, the dynamic storage modulus, E' of the annealed film ( 2 )1378decreased markedly near the Tc from 300 MPa to 10 MPa in water, because of the thermal movement of the surfactant molecules. In water below the Tc of the bilayer, the nonannealed film ( 1 ) gave a lower value of E' than 2, presumably due to the lack of highly ordered arrangement of the surfactant molecules (Fig.7 ( a )). After drying the annealed film again (3), the sharp endothermic peak disappeared (Fig.1 ( d )). High value of E' for 3 (Fig.6, 200-400 MPa) suggests that the phase' transition phenomenon does not occur in the dried film.. The results of ESR measurement of 12-doxylstearic acid as spin probe in the film were consistent with those mentioned above.

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A chelating resin containing dithiocarbamic acid moiety (Q-10) was prepared by the reaction of a spherical poly(vinyl chloride) (PVC) with an aq. ethylenediamine (EDA) soln. to give an aminated PVC, followed by the reaction of carbon disulfide with the aminated PVC. The aminated PVC obtained under the conditions where EDA/PVC mol ratio was 1.5, EDA concentration was 70%, reaction temperature was 116-123°C and reaction time was 4h. was considered to show the the following structural components.
It was found that (A) component reacted with (B) component to give (C) component by SN2 reaction at room temperature during the preservation of aminated PVC. Its reaction rate constant was 3.06 x 10^-3 h^-1 at 60°C and 3.18 x 10-2h-1 at 90°C, and the activation energy was 77.8 kJ?mol^-1. (C) component reacted li ttle with carbon disulfide at 40-45°C. Therefore, it is important to use the aminated PVC which has been kept under certain preservation conditions as an intermediate of Q-10. The relation of preservation temperature (t/ °C) and preservation permissible term (d/day), wac qi-inwn as following eauation.
Q-10 exhibited outstanding resistance for a high concentration aq. soln. ot suit uric acid, hydrochloric acid or phosphoric acid and an excellent adsorption ability for rnercury(II) in these mineral acids, but was decomposed gradually in aq. nitric acid soln. Q-10 had also an excellent adsorption ability for various metal ions such as CH₃Hg⁺, AuCl₄^- and Ag⁺. Studies on Functional Polymer for Separation. III.

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Polyaminated poly(vinyl chloride) (PVC)s were prepared by the reaction of a spherical and porous PVC with polyamines such as hydrazine, ethylenediamine or diethylenetriamine (DET). The aminated PVC (MC-3) prepared by the reaction of PVC with DET showed a good adsorption ability for the metal ions of HgCI₂, CuSO₄, ZnSO₄, CdCI₂, CrCla and Pb (NO₃)₂. and the adsorption for these metal ions was improved by the coexisting of NaC l. The saturated adsorption quantity of Hg²⁺ on MC-3, was large to be ca.1 kg-Hg. (kgRes. )^-1, but it did not show the removal ability of low concentration Hg²⁺ less than 0.0051394mg-Hg.dm^-s. Several polymers were prepared by the reaction of MC-3, epichlorohydrin and amino compounds such as aniline, 3-aminopyridine, p-phenylenediamine, dimethylamine or diethylenetriamine. A polymer bearing anilino end group (MC-5) showed an excellent ability for uranyl ions in a sea water enriched Na₂UO₂(CO₈)₂. The adsorbed uranyl ions were easily eluted with an aqueous solution of ammonium carbonate. Studies on Functional Polymer for Separation. IV.

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TiO₂-ZrO₂ films were prepared by CVD using Ti(O_i-C₈H₇)₄, Zr(O_t -C₄H₉)₄ and O₂ as starting materials under an atmospheric pressure. The effects of deposition temperature and input gas composition on the deposition rate, constituent phase, chemical composition and microstructures of TiO₂-ZrO₂ films were investigated comparing with that of TiO₂ and Zr O₂films. Deposition rate of TiO₂-ZrO₂ films was lowered with respect to the expectations based on each deposition behavior of TiO₂ and ZrO₂ films at any deposition temperature. Though Ti/(Ti+Zr) in TiO₂-ZrO₂ films was in good agreement with expectations from TiO₂ and ZrO₂films at 350°C, it was surplus in Ti at 550°C. TiO₂-ZrO₂ films were consisted of finer particles comparing with TiO₂ and ZrO₂ films.

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The vapor-liquid equilibria of the system noted above were measured over the range of 0.0 003 mole fraction of ethanol in liquid composition to 0.0003 mole fraction of toluene, co rresponding to 0.9997 mole fraction of ethanol, at an atmospheric pressure. The results at the dilute ranges of ethanol and toluene were examined by plotting an infinitely dilute activity coefficient γ ^∞ vs. the reciprocal of temperature T^-1(Fig.3), coefficients which were obtained from the extrapolated, differential ebulliometric and gaschromatographic techniques, and from the values of heat of mixing. The examination showed the results had a good agreement with those of the literature.

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In the preparation of [Co(adao)(NO₂)₂] (adao: -00CCH₂NH(C H₂)₂NH(CH₂)₂NH₂) by using the modified Collman's method, it was found that an nitrocobalt(III) complex other than [Co(adao) (NO₂)₂] could be obtained as reddish orange crystals, The elemental analysis indicated that the complex contained a quinquedentate ligand, 3, 6, 9-triazaundecanedioate (^-COOCCH₂NH(CH₂)₂NH(CH₂)₂NHCH₂COO^-: taud), and had the composition of [Co(taud)(NO2)]. From these facts, it has been found that the aqueous solution of adao pro duced by the modified collman's method contains the above taud as a by-product. It has also been clarified that taud can be easily separated from the solution containing various components by the complex formation of [Co(taud)(NO₂)]. On the basis of the aqueous absorption spectrum of [Co(taud)(NO₂)], its structure has been determined to be trans(O), and the coordination mode of taud is necessarily trans(O). The complex of [Co(taud)(H₂O)]CIO₄ too could be isolated as pinkish red crystals from the reaction product of [Co(taud)(NO₂)] with HCIO₄, , Taking into consideration of the 1H-NMR spectrum and the preparative route for the complex, it has been inferred that the coordinated taud is a linear-chain quinquedentate ligand and has the trans(O) coordination mode.

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