The molecular structure of the complex between copper chlorophyllin (Cu-chin) and flavine mononucleotide (FMN) was investigated by¹H-, ¹³C-, and ³¹C-relaxation times for FMN alone were measured first in order to examine the rigidity and internal motion of FMN. The apparent rotational correlation times of ribose carbons are slightly shorter than those of the carbons on the isoalloxazine ring; this suggests the existence of some degree of internal motion in the ribose chain. The methyl groups showed internal rotation with a correlation time of 4×10^-11 s.
The ¹³C-T₁'s f or FMN in the Cu-chln-FMN complex were measured at 30°C. Computer simulation was applied to determine the probable structure of the complex. The rotational correlation time neccesary in this simulation was esimated from ¹H-T₁ data. The angle between the Cu-chin chlorin ring and the FMN isoalloxazine ring was varied from 0°to 90°and each angle gave a reasonable fit of the calculated T₁'s with those determined experimentally. For a parallel configulation of the two rings, suggested by optical data, the ring-ring distance was determined from the ¹³C-T₁ data to be 4.0Å. The transverse relaxation times measured by ¹H-NMR indicate a partial flow of electron spin from the Cu²⁺ of Cu-chin to the protons of FMN; this suggests that a charge-transfer complex is formed between Cuchin and FMN.

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Humidity-sensing characteristics of the sensor element using antimonic acid proton conductor (Fig.1) were studied at medium temperatures of 100∼200°C. The response rate of the sensor was increased by an addition of diphenylsilanediol binder: with 2 wt% binder, the 90% response time for a change in water vapor pressure (P_H2O) from 7.4 Torr to 43 Torr was as short as 3 min at 105°C, while without the binder it was about 20 min (Fig.2). SEM observation showed that the improvement of response resulted from an increase in porosity of the sensor element (Fig.3). The sensitivity of the element of humidity, i. e., the derivative of electrical impedance (Z) with P_H2O, dZ/dPP_H2O, was considerably large at P_H2O=0.08∼20 Torr at 105°C, while it became smaller at higher P_H2O (Fig.5). The sensitivity coul d be changed by partial ion exchange of H⁺ of antimonic acid with Na⁺ (Fig.7). The sensor was found to exhibit transient behavior before being stabilized. The impedance increased with time for a period of initial about 70 h (Fig.9). Analyses with TG and IR showed that the transient behavior was caused by the formation of hydroxyl groups on the surface of antimonic acid (Figs.10 and 11). The stabilized sensor exhibited relatively good humidity sensing characteristics especially in the low P1120 region (Fig.12). Temperature dependence of the sensor impedance was slight in the range from about 100°C to about 150°C (Fig.13).

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The adsorption behavior of arsenate ions (AsO₄^3-) on hydrous titanium(IV) oxide in aqueous solutions has been studied in detail. The results are summarized as follows: (1) The adsorption of AsO₄^3- was much more effective than that of Cl^- and depended remarkably on the solution pH; e. g., the adsorbed amount of AsO₄^3- was about 50 mg per gram of the adsorbent in a pH range of 2∼3, and decreased gradually with raising pH, although it was still higher than that of Cl^- at pH 10. ( 2 ) Freundlich-type isotherms were obtained for the adsorption from solutions at pH 2 and pH 7, while the slope of the isotherm at pH 2 was smaller than that at pH 7. ( 3 ) While the adsorbed amount of AsO₄^3- on the hydrous titanium(IV) oxide in the amorphous form was slightly larger than that on the anatase form at pH 2, the dydrous titanium(IV) oxide in the anatase form exhibited a much higher adsorba bility than that in the amorphous form at pH 7. ( 4 ) The adsorption rate of AsO₄^3- was hardly affected by the coexistence of Cl^- in the solution at pH 2, whereas it was accelerated 30-fold in the solution at pH 7 by the presence of Cl^- 10 times as much as AsO₄^3-. (.5 )The enthalpy change (ΔH) of the adsorption reaction, +1.62 kcal. indicates that the reaction is endothermic, in contrast to the ion-exchange reaction which is exothermic.
These results suggest that different adsorption mechanisms are operative in the present systern: an ion-exchange mechanism in the low pH region and a non ion-exchange mechanism in the neutral region. In addition, the adsorption behavior of AsO₄^3- was significantly close to that of PO₄^3- among a series of XO₄^n- (X: Si, P, S or Cl) type oxoacid ions.

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Titanium(IV) oxide-alumina composite adsorbents were prepared by hydrolysis of titanium (IV) and aluminum isopropoxide followed by drying and calcining their hydroxides, and their cobalt adsorption in high-temperature water was investigated.
The adsorbent composed of titanium(IV) oxide and alumina, being O.5 5 in mole fraction of titanium(IV) oxide and calcined at 500°C for 5 h showed a surface area of 124 m2g-i and an equilibrium adsorption capacity of 110 μeq⋅g^-1 at 280°C in a pH 4.45 solution containing cobalt ion at 3 ppm. \ The specific surface area of the composite adsorbent decreased with increasing mole fraction of titanium(IV) oxide. However, the cobalt adsorption capacity at 280°C increased with the titanium(IV) oxide mole fraction. Therefore, the cobalt adsorption in high temperature water seems to be controlled by titanium(IV) oxide in the composite adsorbent. From the measured adsorption capacity, it appears that a high specifi c surface area of titanium(IV) oxide in the adsorbent is maintained even when the adsorbent is calcined at the sintering temperature of titanium(IV) oxide.

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In order to clarify the contribution of humus to the adsorption behavior of anionic surfactants onto soil, the adsorption properties of some typical anionic surfactants, such as linear alkylbenzenesulfonate (LAS), α-olefinsulfonate (AOS) and sodium alkyl sulfate (SAS), on humic acid were investigated. Two kinds of humic acid commercially available (Wako and Fulka) were examined. It was confirmed that the Freundlich adsorption isotherm obeys for the equilibrium amount of adsorption of these surfactants below CMC (critical micelle concentration), at which the adsorption amount attains nearly constant values. The Freundlich constant 1/n has nearly the same value, O.75∼0.83, for all the surfactants used and this value is in good agreement with that observed on humus soil. Adsorption of surfactants did not depend on the pH under acidic conditions where the humic acid is insoluble. The effect of alkyl chain length of LAS and SAS was examined and it was found that the adsorption amounts increased with increasing length of alkyl chain and the results agreed with the prediction by the Traube's rule. These results suggest that a hydrophobic effect plays an important role in the interaction of surfactants with humic acid. The effect of temperature on the adsorption amount is not remarkable, but there is a definite tendency which the adsorption amount increases with increasing temperature and then decreases in a higher temperature range.

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Hydrolysis of benzophenone azine, which is an intermediate product in catalytic air-oxidation process for hydrazine synthesis, has been studied in the presence of various acids. Among homogeneous acids, p-toluenesulfonic acid was an effective acid comparable to sulfuric acid. Thus attempts were made to apply sulfonated resins as insoluble acids, which are favorable for separation. Macroreticular sulfonated resins with drybasis moisture content of 20∼50% suspended in toluene at 90°C for 1 h resulted in a high conversion of the azine of 95%. The reaction was rather slow in aqueous 2-butanol. Presumably the acid strength of sulfonic acid was lowered due to solvation in hydrophilic media, while unaffected in hydrophobic media. Selection of the appropriate range of moisture content was essential for such an effective conversion of the azine into hydrazine, and no reaction was observed on a resin which was immersed in liquid water, filtered and used without drying. It has been concluded that the most effective conditions for hydration of sulfonated resins would be near around critical moisture content, which was evaluated as 40∼50% from drying-rate curves, where microspheres composing porous texture were hydrated to the upper limit and the interstices of swollen microspheres were vacant. t Ammonia-Hydrazine Convers i on Processes. XV.

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A simple and convenient method for laboratory scale reduction using Raney nickel (Ra/Ni)has been described. The reduction was achieved by adding sulfuric acid to the mixture of substrate and Rail\li either in aqueous solution or aqueous methanol solution at room temperature. According to this method, numbers of ketones and aldehydes were reduced to the corresponding alcohol in good yields. By use of an excess Ra/Ni, the reduction of ketones containing carbonyl group directly attached to an aromatic nucleus gave the corresponding hydrocarbons. Olefinic double bonds were likewise readily hydrogenated under the same conditions. The selective hydrogenation of unsaturated ketones to the saturated ketones was possible with adjustment of the amount of Ra/Ni used.2

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Catalytic activities of a series of PAN-ACF activated with sulfuric acid for the reduction of nitrogen monoxide with ammonia at 150°C were studied through the kinetics, adsorption and analyses of the surface oxygen groups with ESCA and TPDE techniques. PAN-ACF A and B types which retained a considerable amount of nitrogen exhibited higher activities by the treatment at 400°C for 4 h than C type containing much less nitrogen, although the treatment enhanced the activities of all ACF's. The rate of NO reduction with irreversively adsorbed ammonia was found to be comparable to that of the catalytic reaction. The catalytic activities of ACF's exept for C type were correlated to the multiplication of irreversively adsorbed ammonia and the rate of NO reduction with ACF's, indicating the major contribution of the activation abilities of both reactants to the catalytic activities. The active sites seem to be the surfaces groups containing oxygen which activate ammonia and nitrogen monoxide through acidic and oxidative interaction, respectively.

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The performance of a Pd/a-Al₂O₃ catalyst was studied for a NO-CO-O₂ reaction. The catalytic activity was measured using a cycled feedstream system and a non-cycled feedstream system. The period of the cycling feedstream was varied from 0.1 to 2.0 s.
In the non-cycled feedstream system, the rate of CO oxidation under the reducing conditions was the first order with respect to O₂ and the negative order with respect to CO; the rate of NO reduction was almost similar to that of CO oxidation (Figs.5 and 7). The selectivity for CO-O₂ reaction was much better than that for NO-CO reaction (Fig.6). The NO conversion depended strongly on the stoichiometric ratio (S=(2(O₂)+(NO))/(C0)) and was the maximum at the stoichiometric point (Fig.8).
In the cycled feedstream system, the NO con version was much better than that in the non-cycled feedstream system except at the near-stoichiometric point (Fig.9). The dependence of the NO reduction rate on the O₂ partial pressure decreased with the cycling period (Fig.12). The selectivity for NO-CO reaction was much better than that in non-c ycled feedstream system (Fig.13).
The NO conversion in the cycled feedstream system was calculated from both the rate of NO reduction in the non-cycled feedstream system and the change in the stoichiometric ratio with time in the cycled feedstream system (Figs.14, 15, and 16). The cycling period providing the maximum NO conversion was agreed in both calculated and experimental results but there was small difference in the NO conversion level (Fig.17).
In this system, the periodic operation was found to be effective for the NO reduction and this effect could be explained in terms of the self-poisoning of CO as mentioned in our previous paper.

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The thermal decomposition of synthetic acicular microcrystals of β-FeO(OH) coated with silicic acid has been investigated from 200 to 700°C by means of X-ray diffractometry, thermal analyses, electron microscopy, nitrogen adsorption technique and Mössbauer spectroscopy.
At lower decomposition temperatures, an intermediate, amorphous-like iro n oxide which was transformed into α-Fe₂O₃ at higher temperatures was formed. The temperature range of the formation of the intermediate spread over both high and low temperatures by the increase of silicic acid coating. The electron micrograph showed that the intermediate had needle-like shape and porous structure. The peak of pore radius distribution curves of the intermediates obtained by the calcination at 250°C were ca.1. nm independent of silicic acid content. The pore radius became large at higher calcination temperatures. The maximum surface areas were obtained for the intermediate formed by the calcination at 250°C irrespective of silicic acid contents. The pore volume and the specific surface area of the intermediates increased with the increase of silicic acid content. It was thought that the change in the specific surface area depended on the change in the pore structure. These morphological characteristics were compared with those produced from β-FeO(OH) without silicic acid. Chemical analysis showed that the intermediates contained 2∼8%of chlorine in terms of Cl/Fe. The Mössbauer spectra showed that the intermediate, prepared from β-FeO(OH) coated with 6.1% of SiO₂ by the calcination at 300°C, had an internal magnetic field of 40.4 T at 20°C and was antiferromagnetic with the transition temperature of 200°C. The internal magnetic field decreased by the increase of the silicic acid contents, and increased by the elevation of the calcination temperature. It was considered that these changes depend on the change in size of unit particle which was contained in a porous structure of the intermediate.

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Solid solution of CaMn(CO₃)₂ obtained by the coprecipitation method has been studied by thermal analysis and X-ray diffractometry. Upon heating at 800°C in air, CaMn(CO₃)₂ of calcite structure decomposes to produce a mixture of oxides and complex oxides of Ca and Mn (Fig.2). These products change to a simple phase of CaMnO₃ having the perovskite type structure with heating time, and the crystal also grows (Fig.3). The repetition of heating and cooling cycle of CaMnO₃ in air between 808 and 1120°C resulted in linear weight loss of CaMnO₃ with the rise in temperature due to the increase in oxygen defects. The tendency was reversed by the decrease in heating temperature. DTA curve shows an exothermic and an endothermic peaks at 880 and 890°C, respectively (Fig.5). The crystal structure seems to be changed at 880°C in air by the production and the disappearance of oxygen defects in the CaMnO_3-x.

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In polysulfide solution, sulfide, sulfite, sulfate, thiosulfate and polysulfide ions are contained. These species were analyzed by nonsuppressed ion chromatography with conductometric and UV detectors by using 1.3 mmol. dm-3 potassium gluconate-1, 3 mmol⋅dm-3 boric acid (pH 8.5) as an eluent. Polysulfide ion could be precisely determined as sulfide and thiocyanate ions after cyanolysis, adding 2 equivalents of potassium cyanide for polysulfide sulfur to the sample solution and digesting at 90°C for 10 min in a water bath.
Each of sulfur species in sodium polysulfide solutions was analyzed by the present method and compared with the results obtained by potentiometric titration method. Every sulfur species could be detected by the present method. The recovery of the total sulfur content obtained was about 100%, whereas the potentiometric titration method gave poor recovery. The comparison of the analytical results obtained by conductometric and UV detectors revealed that the former showed better detectability for every sulfur species, and that the latter gave better sensitivity and reproducibility except sulfate ion.

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With the aim of concentrating trace amounts of mercury(II) from aquatic environment, the coprecipitation of mercury(II) with bismuth(III) hydroxide which is produced by adding sodium hidroxide to bismuth(III) nitrate solution was studied in the presence of halogenide ions, amino acids, and sulfur-containing organic compounds. It was found that mercury(II)was completely coprecipitated at the pH from 6 to 10 with bismuth(III) hydroxide when cysteine, thiourea, or thionalide was added at a concentration about 1×10^-4 mol/l to a solution containing 5×10^-9 mol of mercury(II). Cysteine and thionalide, however, interfered with the recovery of mercury(II) from the precipite. Thiourea did not interfere. To 51of sample solution containing 5×10^-9 mol of mercury(II), 15 ml of 10 mmol/l thiourea solution and 15 ml of 1 mol/l bismuth(III) nitrate solution were added, and bismuth=hydroxide was precipitated by adding sodium hydroxide solution. After adjusting the pH from 8 to 9, the suspension was stirred for 60 min, filtered with a 0.45 μm membrane filter, and then dissolved in 20 ml of nitric acid. A small amount of potassium permanganate was added to decompose the thiourea and the solution was made up to 100 ml with distilled water. Mercury was recovered up to 93% by the proposed method.

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The nitration and chlorination of 4-phenanthrol [1] as hindered phenol were studied. Nitration of [1] occurred only at a relatively high temperature of 60°C by treatment with an equimolar amount of 65% HNO₃ in AcOH for 3 h, giving 3-nitro- [2] and 1-nitro4-phenanthrol [3] in 63 and 17% isolated yields, respectively. On further nitration, these nitrophenanthrols gave 1, 3-dinitro-4-phenanthrol [5]. When treated with an equimolar amount of SO₂Cl₂ in AcOH at 50°C for 10 h, [1] gave 3-chloro- [9] and 1-chloro-4-phenanthrol [10] in 41 and 32% isolated yields, respectively. These two products gave 1, 3-dichloro-4phenanthrol [11] on further chlorination. Properties and analytical data of these new substances are given in Table 1. Their structures were confirmed by conversion to known compounds as shown in Equation ( 3 ), but that of [9] was determined on the basis of IR-spectra.
The low reactivity and high o/p ratio observed in the nitration of [1] were interpreted in terms of steric effects.

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Thermolysis of bibenzyl in tetralin and 1-methylnaphthalene as typical hydrogen-donating and -nondonating solvents was studied at temperatures of 400 to 480°C, pressures of 10to 80MPa and reaction time of 4 to 33 min by continuous flow reactor. The main product from bibenzyl was identified as toluene by gas chromatography. Thermolysis of bibenzyl obeyed first order rate law regardless of the changes of its initial concentrations and solvents used. The decomposition rates of bibenzyl decreased slightly with increasing pressure. Such a small pressure effect and the difference of the activation volume of the reaction from the literature value were discussed from a viewpoint of solvent cage effect.
The isomerization of tetralin to 1-methylindan was accelerated by pressure or addition of bibenzyl, and the conversion of tetralin to naphthalene in the presence of bibenzyl proceeded only by hydrogen transfer and dehydrogenation reactions. In the latter case, hydrogen transfer was a dominant reaction, whereas the ratio of the both reactions was independent of pressure under our experimental conditions. Demethylation and oligomerization reactions of 1-methylnaphthalene were observed and both reactions were accelerated with increasing pressure. Radical chain mechanisms were suggested to these reactions by the facts that the reactions were accelerated by the addition of bibenzyl. f Study on Coal Liquefaction. V.

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Grayanotoxins (G-I∼G-XX), all of which except G-I and G-III are minor components, are toxic diterpenoids isolated from Leucothoe grayana MAX. In this report, the conversion of one of the major components (G-III) to several minor components (G-II, G-VII, G-VIII, G-XVII, and G-V) and to hitherto-unknown iso-G-II has been described.
Treatment of G-III with acetic acid in methanol gave G-II. Dehydration of G-III with HCl in methanol afforded G-II. in addition to iso-G-II. Reaction of G-III with anhydrous copper(II) sulfate in dioxane provided G-VII and G-VIII. Oxidation of G-III with N-bromosuccinimide (NBS) gave the 3, 6-dioxo derivative (G-XVII). Treatment of G-III with NBS-CaCO₃ afforded the 3-oxo derivative (G-V). Oxidation of G-III with NaBrO₂⋅3 H₂O gave G-XVII in good yield.

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The optical resolutions of DL-alanine (DL-Ala), DL-a-aminobutyric acid (DL-Abu), DLnorvaline (DL-Nva), DL-norleucine (DL-Nle), and DL-methionine (DL-Met) have been achieved by formation of adduct with L-phenylalanine (L-Phe). An alkaline or aqueous solution containing L-Phe and one of these DL-amino acids was employed as an initial solution. The precipitates composed of L-Phe and the D-amino acid in the molar ratio of 1: 1 were crystallized under appropriate conditions, and the infrared spectra indicated that the precipitates are adducts of the D-amino acids with L-Phe and not mere mixtures of these amino acids. The D-Ala, D-Abu, D-Nva, and D-Met with optical purity of 75∼100% were obtained from these adducts, though the yield of the D-Ala was extremely low. However, the D-Nle obtained had low optical purity. In the case of using an aqueous solution as an initial solution, the L-Nva, L-NIe, and L-Met with optical purity of around 30%, and L-Abu with that of 87.3% were also obtained by further concentrating the mother liquor s, cooling, or adding ethanol. The adducts were crystallized under the same conditions by using a solution of hydrochloric acid containing L-Phe and one of the above DL-amino acids, DL-valine, DL-isoleucine, and DL-leucine as an initial solution. These results suggested that the hydrophobic properties of the side chains in these DL-amino acids influence the results of the optical resolutions.

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Several numbers of Fe(II) salts, Fe(III) salts, Fe(II) complexes and Fe(III) complexes were found to initiate polymerization of methyl methacrylate (MMA) in aqueous solution containing a surfactant under a nitrogen atmosphere. The polymerization of MMA by iron(II) ammonium sulfate (Mohr's salt), one of the above iron compounds, was mainl y investigated. The effective surfactant for the polymerization were as follows; Tween series, Brij 35, Triton X405.2, 2-Diphenyl-1-picrylhydrazyl inhibited the polymerization. The copolymer composition curve for the copolymerization of MMA with styrene agreeded with that of ordinary radical mechanism. On the basis of above results it was considered that the polymerization of MMA proceeded through a radical mechanism. The polymerization of MMA by iron(II) chloride or iron(II) sulfate revealed to proceed through the same mechanism.

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The solution polymerization of 2-amino-4-anilino-6-isopropenyl-1, 3, 5-triazine (AAIT) and 2, 4-dianilino-6-isopropenyl-1, 3, 5-triazine (DAIT) was studied in dimethyl sulfoxide using azobisisobutyronitrile as an initiator. The equilibrium monomer concentration ([M]e) was determined at different temperatures from the relationship between the initial rate of polymerization (Rp) and the initial monomer concentration ([M]o). The heats (ΔHp) and entropies (ΔSp°) of polymerization derived from [M]e were 11.7 kcal/mol and 31.0calfdeg mol for AAIT and. -11.8 kcal/mol and 30.7 cal/deg⋅mol for DAIT. The thermal polymerization of DAIT was also studied by means of a differential scanning calorimeter (DSC). The heat of polymerization (-11.1 kcal/mol) obtained from the dynamic DSC measurement is in good agreement with that measured by [M]e which was determined by the isothermal DSC measurement.

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The ordinary process for manufacturing gelatin from chrome-tanned leather discharges a large quantity of wastewater containing chromium and organic substances dissolved by acid. Since sulfuric acid used in the ordinary process induces the problems of wastewater, the authors tried a modified method for preparing gelatin by lime treatment without sulfuric acid.
After liming for 3 d, washing and pH adjustment, the limed leather was treated for 3 h at 70°C. Gelatin was obtained in 40% yield and its quality was good: viscosity 158mp, gel strength 415g, chromium content 30∼70 ppm, calcium content 0.8∼0.2%. When the extraction was continued for 2 h at 90°C after extraction at 70°C, gelatin was further obtained in 40% yield, but its quality was not good as compared to that of the gelatin extracted at 70°C.
The chromium(III) in liming solution and wash water was less than 0.09 ppm and chromium (VI) was not detected. The chromium in the chrome-tanned leather could be rec overed as unextractive residue. The water pollution will be improved by the method developed here. However, the further study is necessary for obtaining the better yield with less calcium content.
On liming chrome-tanned leather, the color changed, the denaturation temperature was lowered and calcium content increased. These data indicate that the lime soak brings about dechromination and subsequently free carboxyl groups in collagen molecule forms calcium salts.

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Organic wastes are thermally decomposed into gas, oil and/or solid residue which are used as fuels, starting materials for industry or substances for reclamation. Heavy metals in organic wastes may give rise to secondary environmental pollution through the thermal decomposition process.
Inthis study, wastes of PVC resins, rubbers, lubricating oils and coatings were subjected to dry ashing or wet ashing treatment followed by determination of Cd, Zn, Pb, Cu, Fe and Cr in them with flame atomic absorption spectroscopy. Next these organic wastes were decomposed in a stream of air at various temperatures (390∼1000°C) with the decomposition apparatus as shown in Fig.1, and then the content of heavy metals in the resulting residues were determined by the method described above. The evaporation behavior of these heavy metals w ere different from one another, depending on the origins of the wastes as well as their composition.
Cadmium in the waste of PVC resin evapo rated at the lowest temperature (550-750°C)among the heavy metals tested. Zinc in the waste of PVC and four heavy metals (Zn, Pb, Cu and Fe) in the waste of water-soluble lublicating oil and of the emulsion coating evaporated at the temperature around 750°C, while Zn in the wastes of synthetic rubber containing carbon black evaporated at about 900°C.
Heavy metals (Zn, Pb, Cu, Fe and Cr) in m ost of other wastes tested were found to remain in the residues after thermal decomposition.

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Complex resins obtained by the reaction of polyethyleneimine with maleic anhydrideisobutene copolymer around 100°C revealed selective ion adsorption depending on the equivalent ratio of nitrogen to carboxyl group (N/COOH). In detail, polyanion-excess complex resins (N/COOH<1) have high adsorption capacity especially for metal cations such as Cu²⁺, Pb²⁺, Zn²⁺ and NO+, and resins containing excess polycation (N/COOH>1) for metal com plex anions such as [CrO₄]^2-, [Ag(S₂0₃)₂]^3- and [Fe(CN)₆]^4-. Furthermore, the polycationexcess complex resins had high adsorption capacity for uranium in solution, for example, a polycationic resin (N/COOH=1.79) had an adsorpion capacity of more than 100 mg U/g-dry base resin in a 75 ppm uranium solution. It also adsorbed and recovered uranium from solution contatining such infinitesimal amounts of uranium as sea water.
The results from electron probe X-ray microanalyser (EPMA) of a polycationic resin (N/COOH=1.79) indicated that cations such as Ca²⁺ and Mg²⁺, abundant in sea water, were not adsorbed at all while such anions as Cl^- and S^2- were adsorbed. It was found that Br^-, I^-, etc. were not adsorbed from sea water while these anions were adsorbed from the solutions containing them independently. The result indicated that Cl^- in sea water probably interfered the adsorption of Br^-, I^-, etc. However, uranium was adsorbed from sea water in spite of its extremely low concentration without any disturbance of other co-existing ions. It was found that Ni²⁺ and Cu²⁺ were also adsorbed. Further investigation is required on these points.

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The complexation reactions of iron(II) with four water-soluble hydrazones derived from 2-(3-sulfobenzoyl)pyridine have been investigated kinetically by using a stopped-flow spectrophotometric technique. The rate of the complex formation is proportional to each of the concentrations of iron(II) and hydrazone and independent of the hydrogen ion concentration. On the basis of these results, the rate-determining step in each reaction system was found to be the 1: 1 complex formation reaction between iron(II) and undissociated hydrazone. The rate constants and activation parameters at an ionic strength of 0.2 and at 25°C were calculated. Further, it was clarified that the difference in the rate constants including that of 2-pyridyl(3-sulfophenyl)methanone 2-pyrimidinylhydrazone (PSPmH) reported previously is attributed to the difference in the structure of the complex.

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The formation of the complex between synthetic fluorine micas, Li-taeniolite [LiMg₂Li (Si₄O₁₀)F₂] and Na-F-hectorite [Na_1/3Mg_{2 2/3}Li_1/3(Si₄O₁₀)F₂], and aluminum phosph ate was studied at various reaction conditions in order to elucidate the factors affecting the reaction and mechanism of complex formation. The complexes were formed from the suspension of fluorine micas in the solution of AlCl₃, Ca(OH)₂ and H₃PO₄ in certain concentration ranges. The compositions of interlayered materials and basal spacings of the complexes varied with the concentration of solution, the reaction time, and the particle size and layer charge of starting samples. The interlayered materials can be generally expressed as n[Al(PO₄)x(OH)y], where PO₄/Al ratio increases with reaction time and finally tends to converge to a value in the range of 0.8∼M.9. These results suggest that the aluminum phosphate complex is formed through an intermediate, so-called Al-hydroxy complex.

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Chlorophyll a (chl a) could be dissolved into water in the presence of deoxyribonucleic acid (DNA). The electron specrtum of this water-soluble chl a differed from that of chl a in petroleum ether which ccntains 0.5% isopropyl alcohol (PI solution). Fluorescence quanturn yield of water-soluble chl a was O.070 times larger than that of chl a in PI solution.
Chl a in PI solution was completely photobleached by 10 min photoillumination, but water-soluble chl a was not photobleached at all even by 30 min photoillumination.

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The Adsorption and reaction of formic acid were studied on waste mold sand for its application to the removal of injurious acid gases. The mold sand containing sodium carbonate chemisorbed completely formic acid vapor (4.4 vol% in air) at 50°C. The sm aller the particle size of sand, the higher the rate of adsorption, the particle size of 30 μm being the best choice. The catalytic decomposition of formic acid was observed at temperatures higher than 100°C.
The sand accelerated preferentialy the dehydration reaction at temperatures lower than 275°C, but at higher temperatures both dehydration and dehydrogenation reactions were catalyzed.
The waste mold sand can be used as a catalyst material for the removal of formic acid vapor.

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