Cobalt-ruthenium mixed metal catalysts have been revealed to show synergistic effect on carbonylation reactions such as homologation of methanol and hydroformylation of olefins. Especially, the catalytic activity of Co₂(CO)₃ for the hydroformylation of cylohexene is greatly improved by the addition of Ru₃(CO)₁₂. The hydroformylation by the bimetallic catalyst is remarkably influenced by the nature of the solvent. The synergistic effects for cobalt and ruthenium on these reactions are discussed.
A series of tetrahedral mixed metal clusters M[RuCo₃(CO)₁₂] (M=Na, Et₄N, Ph₄P, PPN, H) have been prepared by reaction of RuCl₃ with 4 molar equiv of Na[Co(CO)₄] followed by cation exchange or protonation. These clusters are also effective for above carbonylation reactions. Metallo-selective substitution reaction of CO ligand in HRuCo₃(CO)₁₂ by amines or phosphines has been discovered. The substitution of amines takes place preferentialy at the ruthenium atom whereas the substitution of phosphine occurs exclusively on the cobalt atom(s).

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The air electrode properties of Pd and Ni metals deposited on an active carbon fiber felt (KF-felt) were examined reffering to a zinc electrode. The maximum power, which w as evaluated from the electric power-current curve for the zinc-air cell at 40°C in air, increased linearly with the amount of Ni deposit up to 50 mg/g-felt. The maximum power for Pd deposited electrode reached a maximum value at 18 mg/g-felt of Pd; it remained constant with deposited Pd between 18 mg and 112 mg/g-felt. The discharge current was measured under the constant terminal voltage O.75 V between 20 and 50°C with the oxygen partial pressure from 0.2 to 1 atm. The current density depended on the temperature. It also varied with the oxygen partial pressure in accordance with Langmuir relation. The apparent activation energy (Ea), the 'relative values for the oxygen adsorption equilibrium constant (b) and of the product (k₀.⋅a) of the apparent rate constant (k₀) and the adsorbed amount for the monolayer (a) for the oxygen activation process on Pd (18 mg) and Ni (50 mg)/KFfelt were estimated as follows: Ea =27 and 24 kJ/mol, b=3.3 and 3.1 atm^-1, k₀.⋅a =83 and 26mA/cm², respectively. By comparing these kinetic data with the corresponding values for Pt (167 mg)/KF-felt, 20 kJ/mol, 0.34 atm^-1, and 167 mA/cm², the Pd metal deposited on KFfelt clearly indicates an excellent catalytic activity in comparison with the Pt deposited in spite of a small amount of the deposit (2.4 mg/cm²).

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Dynamic and static light scattering from chlorpromazine hydrochloride (CP) micelles was measured in 0.07, 0.139, 0.154 and 0.3 M (M=1 mol dm^-3) NaCl solutions. The critical micelle concentration (cmc), apparent molecular weight (M_M) and the second virial coefficient (A_2M) were obtained by light scattering intensity measurements. The diffusion coefficient 1(D)was measured by the dynialtic light scattering method. The hydrodynamic radius of micelles RH was calculated from D_CMC, using the Stokes-Einstein equation. The cmc decreased and M_M increased with NaCl concentration. Linear relationships are established between D and solute concentration (c) in three dilute NaCl solutions: D=_CMC (1+ac). In 0.3 M NaCl, however, D decreased nonlinearly with c. A clear correspondence was obtained between the static and dynamic light scattering results. The linear relationships are also I established only at lower three NaCl concentrations between Kc′/Rθ′ and c′ of the equation Kc′/Rθ′=1/M_M+2 A_2Mc′, where Rθ′=Rθ-Rθ_CMC is reduced Rayleigh ratio and c′=c-cmc is the reduced concentration. But in 0.3 M NaCl the relation is not linear and. A_2M<0. At lower electrolyte concentrations CP micelles are stable thermodynamically and hydrodynamically, and intermicellar interactions both repulsive and attractive dominate micellar diffusion. In O.3 M NaCl solution of high ionic strength, CP micelles formed at cmc are not stabl e and grow up with increasing size shown both in RH and M_M values.

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The vapor-phase carbonylation of methyl chloroacetate (MCA) with carbon monoxide in the presence of methanol was carried out in order to investigate the catalysis of metal halide supAported on the carrier appropriate for the formation of dimethyl malonate (DMM).
Activated charcoal seemed to be suitable for the carrier with rhodium(III) chloride, while methyl methoxyacetate and methyl glycolate were formed in significant amounts on use of active aluminium oxide. The conversion of MCA into DMM increased with increasing th e surface area of activated charcoal with a few exceptions.
The metal chloride capable of forming carbonyl compo u nds was supported on the activated charcoal and was examined for the carbonylation of MCA into DMM. Cobalt(II) chloride, rhodium(III) chloride, palladium(II) chloride, iridium(III) chloride, iridium(IV) chloride and pulatinum(IV) chloride were found to be active for the carboylation. In particuler, rhodium(III) cuhoride was excellent in the reactivity and selectivity. The amount of methylacetate varied widely depending on metal chlorides supported on activated charcoal. It was not possible to suppose all methyl acetate is formed by the release of carbon dioxide from methylhydrogen malonate. It could be assumed that MCA reacted directly with methan ol to convert into methyl acetate and methyl chloride.
Among the rhodium compounds the electronegative substituent group bonded to the rhodiumcontributed to a increase in the reactivity. Metal iodies enhanced remarkably the reactivit of rhodium(III) chloride supported on activated charcoal . The reactivity of promoter was found in the following order : NaI>LiI>KI>BaI₂>CsI>CoI₂>RbI>CaI₂. It was reasonable to speculate that rhodium(III) chloride iodide might be formed by replacing the chlorine of rhodium(III) chloride with iodine partly and preferable to carbonylation of MCA into DMM.

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The seasonal variation of atmospheric concentration and size distribution of particulate mercury have been investigated from March 1985 to April 1987 in Chiba. Particulate mercury was collected on glass fiber filters after separated into nine size fractions by an Andersen sampler. The particulate mercury was determined by flarneless atomic absorption spectrophotometry coupled by a combution-gold trapping-heat vaporization procedure.
At first, the seasonal variation was observed for the atmospheric concentration of particulate mercury and it was found that the particulate mercury in atmosphere had a tendency to become low in concentration during summer and high in winter. The correlation proved that the tendency is contrary to the total mercury concentration in urban air. This seasonal variation in the mercury concentration in the atmosphere is ascribed to seasonal. temperature differences. It has been suggested that the mercury in the atmosphere might behave in a gas from under relativly high vapor pressure and atmospheric temperature, and in a aerosol from under low vapor pressure and atmospheric temperature.
The size distribution of particulate merc ury was usually a bimodal type in all season. Their peaks appeared in coarse particles (above 2 μm) near 4 um in diameter and in fine particles (below 2 μm) near 0.8 urn in diameter. Their size distributions were usually fine mode. The seasonal variation of coarse particles was hardly observed; whereas fine particles were predominant in the autumn and winter.
In late autumn and early winter, i t is known that the concentrations of typical heavy metals, aerosols, chlorides and nitrates released from artificial work sources, increased in fine particles and thier size distributions were fine mode, in Japan.
From these facts, it could be explained that the particulate mercury in atmosphere might be formed by the following factors: 1) The drop of atmospheric temperature and vapor pressure. 2) The amalgamation of gaseous mercury with heavy metals. 3) Adsorption of gaseous mercury onto the surface of fine particles. 4) The compounds formation between chloride or nitrate and gaseous mercury.

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Quartz stills for sub-boiling distillation were newly devised for the purification of analytical reagents such as acids, aqueous ammonia and organic solvents. Compared with those used previously, new stills of better quartz quality have a larger surface area for vaporization of liquid. Distillation rates were improved, for example, those of HNO₃ being 0.287 and 0.993 kg⋅d^-1 at 75 and 95°C, respectively. Without being exposed to the atmosphere, a purified reagent can be transferred to a neighboring still for second sub-boiling distillation. Purification degrees were examined by the use of isotope dilution surface ionization mass spectrometry which had been developed to measure each, 10^-11g of Ag, Cd, Cu, Ni, Pb, Tl and Zn. Final concentrations of impurities in water, hydrochloric acid, nitric acid, perchloric acid, acetic acid, aqueous ammonia, chloroform and ethanol were at a level of 10^-9 g⋅kg^-1. As for heavy metals, the present method can give reagents purer than those ever reported.

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In order to help characterization of organic pollutants released from coal and to assess their possible health effect, several fused furans were synthesized as reference material by starting from simple phenols [1a]-[1u]. By the oxidative coupling of phenols [1c], [1d], [1f], [1l], [1m], [1t] with potassium hexacyanoferrate in alkaline media, 2, 2′-dihydroxybiaryl [2d], [2d, m], [2d, t], [2m, t], [2t] were obtained. Successively, they were converted, to diden-zofuran-type fused furans [4′d], [4d, m], [4′d, t], [4m, t], [4t], [4′t] in 4.2-57% yield by their dehydrative cyclization using phosphoric acid, 2, 3-dichloro-5, 6-dicyano-p-benzoquinone (DDQ) or bromine. On the other hand, condensation of phenols [1a], [1b], [1e], [1u] with 2, 3-dickloro-1, 4-naphthoquinone (DCNQ) in pyridine, afforded fused furans [5l], [5m], [5q], [5t] with dinaphthofuranquinone structure in 18-98%

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The condensation reaction of. phenols [1a]-[1j] wiih chloranil in pyridine afforded benzoquinone-annulated furans [3d′], [3e′], [3h′], [3i′], [3i′] with in 2.6-26% yield. Hexacyanoferrate(III)-aided oxidative coupling between 1, 3-dicarbonyl compounds [1h], [1k], [1l] and dihydric phenols [1c], [1f] provided 8, 9-dihydroxy-6 H-benzofuro[3, 2-c][1]benzopyran-6-one [2c, h] and 2, 3-dihydroxybenzo[b]naphtho [2, 3-d]furan-6, 11-dione[2c, k]. Subsequent condensation reaction of these dihydric phenols with 2, 3-dichlo ro-1, 4-naphthoquinone (DCNQ) gave heptacyclic fused furans [3c, h], [3c, k] in 17 and 25% yields, respectively. Using the Rössing′s reaction, naphtho[2, 1-b]furan [3m] and 3-phenylbenzofuran [3n] were synthesized from (1-formyl-2-naphthyloxy)acetic acid (2′m) and (2-benzoylphenoxy)acetic acid (2′n) in 14 and 30% yields, respectively. Nitration of fused furans[3e, j]-[3n] yielded nitro compounds [4e, j]-[4n] each with 1-4 of nitro groups being introduced.

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Decomposition of ethylene glycol by ozone under ultraviolet irradiation was studied by changing the concentration of ethylene glycol, that of ozone in the feed gas, and the irradiation intensity of a low pressure mercury lamp.
The overall reaction rate was represented as follows.
where k is rate constant, I is the irradiation intensity of a low pressure mercury lamp, F is the concentration of ozone in the feed gas, and C is that of ethylene glycol. Oxalic acid, glyoxylic acid, glyoxal, glycolaldehyde, formaldehyde and formic acid were detected as decomposition products, and the removal of total organic carbon (TOC) was observed too. Based on the decomposition behavior of ethylene glycol and change of its decomposition products, the decomposition route was estimated.
From the estimation of the decomposition route and the fact that a considerable amount of oxalic acid was produced, it was suggested that the TOC removal via oxalic acid was more important than that via formic acid. The TOC removal was affected by the concentration of ethylene glycol in addition to that of ozone in the feed gas and the irradiation intensity of low pressure mercury lamp.

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The reactivity in the pyrolysis of alkylp*h e nylsulfonium bis(methoxycarbonyl)methylides was investigated for four kinds of derivatives (S-alkyl groups are ethyl [1], propyl [2], butyl [3], and 2-phenylethyl[4]). The rates of the pyrolysis of all substrates gave a good fit to first-order kinetic equation (r=0.999). Rate constants of the sulfonium ylides for [1], [2] and [3] were 3.7 -4.5×10^-4s^-1, at 150°C, while that for [4] was 23.1×10^-4s^-1. Acti vation parameters for the sulfonium ylides calculated from the Arrhenius equation were as follows; Ea=ca.135 kJ⋅mol^-1, and ΔS= -2.4--3.9 JK^-1⋅mol^-1. Substituent effect of Sphenyl group of [1] correlated well with Hammett ρ constants with a ρ-value of +0.45(r= O.997).
The reactivity of [1] in the pyrolysis was compared as a reference substrate' with those of other related substrates such as ethyl phenyl sulfoxide [5], and S-ethyl-S-phenyl-Ntosylsulfimide [6]. The ratios of the reactivity: [1], 1.0; [5], 0.7; [6], 42.1, indicated that the reactivity of the sulfonium ylide was similar to that of [5], but considerably, lower than that of [6]. It was thus suggested that the pyrolysis of the sulfonium ylides may proceed essentially via E 1 type mechanism in Ei reaction.

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With the purpose to obtain humic. acid from peat, an investigation was conducted to examine the conditions of dry oxiation using nitrogen dioxide.
By the reaction for 6 h using 1 vol% of nitrog en dioxide with a space velocity of 1000 h ^-1, a product containing 80 wt% humic acid was formed in a yield of 107 wt% based on the starting material.
The am ount of humic acid derived from peat did not increase even with a prolonged reaction time.
As the reaction behavior was found to be very similar to the reaction model of Jander′s equation, it was suggested that the rate-determining step in this oxidation is the internal diffusion of an oxidizer.
By increasing the nitrogen dioxide concentration to 34 vol%, the reaction ended in 1/6 of the time taken for the previous case, and the amount of humic acid contained in the resultant product was almost equal to the former reaction.
It was concluded that this oxidation me thod is superior, when compared with conventional nitric acid and air oxidation methods, in the following points: higher yield of oxidized peat, higher content of humic acid, and no operations such as waste processing.

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Ternary metal complexes comprising an aromatic amino acid and an aromatic amine such as 1, 10-phenanthroline (phen) and 2, 2′-bipyridine have recently been shown to have the intramolecular aromatic ring stacking in dilute aqueous solution. With a view to understanding the precise binding mode of the stacking interaction, the crystal structure of [Cu(phen)(L-tryptophan)]ClO₄⋅2.5H₂O has been determined by the X-ray method. Crysta ls of the complex are orthorhombic, space group P 2₁2₁2₁ with a=28.362 (28), b=11.063 (5), c=8.139(12) A, U=2554 (4) Å3, and Z=4. The geometry about the copper(II) ion is five-coordinate square-pyramidal, with the two nitrogen atoms of phen and the nitrogen and oxygen atoms of L-tryptophan coordinated at the equatorial position in an apprOximately planar form and one oxygen atom of the carboxyl group of the neighboring complex molecule at the axial position. The most interesting structural feature of the complex is the existence of the intramolecular stacking between the L-tryptophan indole ring and the aromatic rings of phen with the average spacing of 3.51Å from the vacant axial position. To understand the binding mode of the stacking interactions, we calculated the charge densities of a model system, protonated phen-L-tryptophan, by the CNDO/2 MO method. The charge densities obtained from the MO calculation suggest that the intramolecular stacking interactions are dominated by the electrostatic interactions between the two aromatic rings.

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Passive transport of amino acid derivatives by a variety of lipophilic amines or the amines combined with crown ether was carried out in a chloroform liquid membrane system containing N-benzoylamino acid salt of tris(hydroxymethyl)aminomethane in the source phase (phase I) and tris(hydroxymethyl)aminomethane in the receiving phase (phase II) under the initial conditions shown in Tables 1 and 2.
All of the amines examined in this novel s ystem were found to mediate the transport of four kinds of N-benzoylamino acid (BzGly, BzSar, BzAla, and BzPhe) with much higher efficiency than those by crown compounds in the known systems (Tables 1, 2, and 3).
In comparison among the amine carriers with the same total number of carbon at oms in the molecule, the order of the efficiency was primary<<secondary<tertiary. And the transport efficiency for BzAla increased with increasing alkyl chain length of primary amine, but in the case of tertiary amine an optimum chain length was observed for the transport. An apparent enhancement of transport efficiency due to cooperative action was observed only for the combination of primary amine and crown ether as a carrier (Tables 1 and 2). The order of the transport rate for the substrates was BzGly<BzSar<BzAla<<BzPhe, regardless of kind of the carriers used, but primary amines had the highest substrate-selectivity (Table 2).
These results were explained mainly in terms of lipophilicity of the carriers and the substrates.

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Network bis(phthalonitrile) polymers were prepared by thermal polymerization of 4, 4′-(4, 4′biphenylyienedioxy)diphthalonitrile (BPPN) or the mixture of BPPN and tetracyanobenzene (TCB) in the presence of amine coreactants. The pyrolysis of these polymers was performed in a nitrogen atmosphere at temperatures stepwise elevated at an interval of 50°C. The thermal degradation began at about 450°C and was accelerated with increase of temperature. In the pyrolysis between 600 and 650°C, remarkable increases in density and elastic modulus were accompanied with a simultaneous sharp drop in resistivity. From results of X-ray, Raman, FT-IR, and 13C CP-MAS NMR measurements, it was found that the two-dimensional partially carbonized structures containing a considerable amount of nitrogen were formed for the pyrolyzates pyrolyzed at 500-700°C.
In the pyrolysis between 80 0 and 900°C, the planar cyclic structures formed at the temperature of 600'-650°C were partially broken into the three-dimensional networks of amorphous carbon with the progress of carbonization. The highly carbonized pyrolyzate of moulded sheets was found to have a density of I.65 g/cm³, an elastic modulus of 27 GPa, and a resistivity as low as 0.02 Ωcm.

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It has been studied on influence of moisture content in Nylon 6 pellet on the processability in the spinning and drawing for fiber production and on the tensile strength of the tyre yarn produced.
The experimental result showed that the optimum moisture content of the pellet was required to give minimum frequency of filaments/yarn break in drawing and maximum tensile strength of the yarn. This optimum moisture content was not more than water solubility in polymer melt at the remelting temperature of extruder/spinhead and brought no or little increase in relative viscosity of the polymer by remelting (Figs.4 & 5).
The moisture content of zero relative viscosity change can be calcu lated in the following formula:
here K: polycondensation equilibrium constant at remelting temperature
P: number-average degree of polymerization of the pellet
a and b: mole fraction of viscosity stabilizers, acid and amine type each.

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The permeation behavior of various carboxylate ions through an anion-exchange membrane have been studied by means of the measurements of the electrodialysis in the mixed solution of sodium carboxylate and NaCl, the.. Donnan atisorption, the electric conductivity, the water content, the water-splitting phenomenon and the current-voltage curve.
The permeability of carboxylate ions was smaller than Cl except salicylate ion. The poor ciirrent efficiency (<50%) of the concentration was Observed in the mixed solution system s of aromatic carboxylateshnd NaCl. The conductivity and the water content of these carboxylate ionic-form membrane were very small compared with those of Cl^-, HCO₂^- and CH₃CO₂^- in spite of the abnormally large Donnan adsorption. Whereas the anion-exchange membran e was subjected, to water-spl, itting at a lower currept, density easily in, HCO₂Na and CH₃CO₂Na solutions than in NaCl solution, the water-splitting of the membrane was not observed even at higher current density than in CH₃CO₂Na, HCO₂Na and NaCl solutions in aromatic carboxylate solutions.
These results wi ll be explained by considering poisoning of the anion-exchange membrane by the aromatic carboxylate ions. These ions were tightly exchange-adsorbed to the fixed ionic group in the anion-exchange membrane, and consequently the effective fixed charge concentration in the membrane decreases, and the membrane apparently become a non-charged membrane Le., less-permselective membrane.

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Methyl derivatives [3d] of benzo[1, 2, 3-kl: 4, 5, 6-k′l′]dixanthene [3a] were synthe; ized by the cyclization of 1, 5-diphenoxyanthraquinones, which were prepared from 1, 5-dichloroanthraquinone and potassium salt of cresol or xylenol. Electronic absorption spectra of [3b]-[3d] showed almost the same profile as that of [3a]. The photooxidation of the above red compounds[3b]-[3d] with visible light of 541 nm gave the colorless endoperoxides[4b]-[4d]. Tetramethyl derivative [3d], which is the most sterically hinder ed one among the compounds from [3a] to [3d] photooxidized about 1.5 times faster than [3a]-[3c]. Endoperoxide [4d] showed better thermal stability than those of [4a]-[4c].

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Dunaliella sp. cells were analyzed for the concentration and chemical speciation of arsenic accumulation by using diethyldithiocarbamic acid-Ag/pyrizine method and benzene extraction. The growth of Dunaliella sp. was affected by the addition of arsenate more than 1.0 mg⋅l^-1. The amount of accumulated arsenic by Dunaliella sp. cells increased rapidly at initial stage and became maximum within 6-20 h. The maximum accumulation of arsenic depended both on the growth phase and on the arsenate concentration.
Arsenic excretion was observed after the arsenic concentration in Dunaliella sp. cells had reached a maximum in all cases. The arsenic in Dunaliella sp. cells was in the forms of arsenate, arsenite and organic arsenic, and most of it was arsenate.

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Galvanostatic electrolysis of an aqueous suspension of E. coli (AB-1157) containing 0.45 wt%NaCl was studied. The surviving fraction of E. coli decreased upon electrolysis in the presence of NaCl. However the fraction did not change in the absence of NaCl or in the case of no electrolysis. The apparent energy required for 99% sterilization was constant irrespective of the current density, and increased in proportion to the reciprocal of NaCl concentration. The 99% sterilization energy in the electrolysis was less than that in the γ-radiolysis by a factor of about 100. The lethal damage of E. coli (AB-1157) was accelerated by dissolved oxygen, as observed in the aerated and oxygenated systems, but was not induced by preelectrolysis of an aqueous NaCl solution for 4 min at 1 mA followed by incubation of E. coli.

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The reaction of propylene oxide (PO) with dichloroacetic acid (DCA) in the presence of lithium dichloroacetate was studied kinetically in ethereal solvents, dioxane and diglyme. The ring-opening of PO obeyecl the following kinetics,
ν=k3(a-x)²(b-x)+k2(a-x)(b-x)
k2=k′3C0
where a-x, b-x, and C0 are the concentration of DCA, PO, and lithium dichloroacetate, respectively. The reaction was accelerated to a considerable extent by the addition of lithium dichloroacetate. The linear relationship between k2 and C0 was not observed, and the higher the common salt concentration, the less the extent of acceleration of the reaction, which is presumably due to the association of the lithium salt. Then the rate constant k′3 was estimated from the slope of the above curve at C0=0. The acceleration of the reaction could be accounted for by the activation entropy rather than the activation enthalpy.

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On irradiation, the title compound (HPT) in various organic solvents saturated with N₂ yielded the dimerized products, 2, 2′-dithiobis[pyridine] and 2, 2′-dithiobis[pyridine] 1, 1′dioxide. The results of triplet-quenching experiments suggest that the reaction proceeds preferentially through the excited singlet state. The mechanism of this dimerization reaction was discussed based on the results of the solvent-viscosity and HPT-concentration effects on the quantum yields for the disappearance of HPT.

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Treatment of grayanotoxin (G)III With oxalic acid in methanol gave G-II iso-G-==II and 1, 5-seco derivative. The structure of 1, 5-seco derivative was identified by comparison of its IR and NMR spectra with those of 3, 6, 14, 16-tetrahydroxy-5, 10-seco-ent-kaurl (10)-en-5-one. It was clarified that the 1, 5-seco compound was an intermediate in the transformation of G-III to G-II and iso-G-II.

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A macromolecular complex (MC) consisting of [2-(diethylamino)ethyl]dextran, (carboxymethyl)dextran, and poly(vinyl sulfate)was prepared in a solution of 1.10 mol⋅dm^-3 and was cast into the membrane from the casting solution. The transport behavioF of Na⁺ through the MC membrane was investigated in the systems of [PVSNa+PVSH (aq.)/NaOH (aq.)] and [NaCl+HCl (aq.)/NaOH (MeOH)]. In the former case the transport ratio was much higher than that in the [NaCl+HCl (aq.)/NaOH (aq.)] system, because the membrane potential difference i. e., the driving force of the transport, was large and maintained for a long time. In the latter case, the transport ratio was also higher, since Na⁺ was transported by the potential energy.

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The iron(III) hydroxide sulfate solution of pH 1.5 is considered to be consisted of various complex cations on the basis of experimental results obtained by numerous investigators. The scanning electron micrographes revealed that the macromolecular complexes consists of iron(III) hydroxide sulfate and sodium metaphosphate or poly(potassium vinyl sulfate)comprised of two different phases or one phase.

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