Small amount of Co, Ni or NO^3- ion was added to a matrix solution CaCl2-1-120 system with various concentrations and the structural change of each ion was investigated in terms of visible and infrared absorption spectroscopy to study the effect of the concentration of a matrix solution on it.
The structure of added ion was appreciably affected by the composition of this solution. It was observed that the coordination number of Co"or Ni"ion changed from six to four and the molecular symmetry of NO₃ ion changed from D3, to C_2C, in terms of the ionic interaction with increasing concentration of matrix solution. These changes took place at the concentration of 3--4molg of CaCl2 and at the vicinity of the above concentration, the matrix solution had 12 water molecules per one calcium ion. However, the effect of concentration of added ion was not observed in the concentration range of this work.
On the basis of these results, it was concluded that the structural change in added ion occurred from a deficiency of water molecules to bring about the normal hydration and from a change in solution structure from water-like to molten salt-like structure. And also, it was proposed that the added Co", Ni"or NO^3- ion was a useful indicator for finding a change in structure of the aqueous solution.

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The permeation rate of hydrogen through a palladium membrane was measured at upstream hydrogen pressures ranging from 0.01 to 1 atm and at temperatures from 27 to 100° C. For a uniphase palladium membrane, either ce- or 8-phase, the permeation rate was expressed as a function of the upstream hydrogen pressure, the downstream hydrogen pressure, the membrane thickness, and the Fick diffusion coefficient (Figs.2, 3, 4). The permeation force was explained to be drived by the difference in concentration of dissolved hydrogen between both surfaces of the membrane in equilibrium with the hydrogen pressure in the gas phase. For a palladium membrane consisting of both a- and R-phase, a hysteresis was observed on the permeation rate vs. hydrogen pressure curve (Fig.9), indicating that the hydrogen pressure at a 8 phase transition differs from that at a phase transition.
The hydrogenation rate of ethylene by permeated hydrogen through the palladium membrane was measured at 100° C over the hydrogen pressure ranging from 0.01 to 1 atm and over the ethylene pressure ranging from 0.01 to 0.8 atm. It was analyzed that, at low pressures of ethylene, the overall rate of reaction controlled by the reaction on the palladium surface is proportional to the ethylene pressure and that, at higher pressue of ethylene, the overall rate is controlled by the diffusion of hydrogen through the palladium membrane, which is expressed as a function of the upstream hydrogen pressure (Fig.11).

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The photochemical reaction of butyl p-hydroxybenzoate (BHB) initiated by irradiation of Hg 3650 A in sodium nitrite aqueous solution was studied. Butyl 3-nitro-4-hydroxybenzoate (BNH) was produced as a main product of photochemical nitration reaction. The quantum yield of the formation of BNH, OBNH was 0.012 under conditions of 8 mmol/l BHB, 0.115 moll NaNO₂, and pH 9.7. The reaction was enhanced in a NO, -bubbled solution but hindered by the addition of sodium thiocyanate and sodium bromide which were used as OH radical scavengers (Table 2). Thus, it is suggested that both of H radical and NO₂ are involved in the nitration reaction. by photodecomposition of nitrite ions in aerated aqueous solution. The reaction mechanism is proposed based on the addition of H to the aromatic ring of BHB and the successive reaction of NO₂. The electron abstruction from NO₂ by the OH-adduct may result in the nitration.

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The reduction characteristics of silica supported nickel oxide-chromia composite catalysts were investigated by the thermal analysis method. The catalysts were prepared with impregnation and coprecipitation. The reduction peak of chromia appeared at 300° C. The thermal analytical data of the nickel oxide-chromia composite catalyst showed that this reduction peak is attributed to the reduction of CrOe contained in Cr2O^2- and that the peak shifts 300° C to 150-170° C due to hydrogen on a small amount of nickel in a reduced state. The reduction curves of impregna tion catalysts differ markedly from those of coprecipitation catalysts at higher temperatures, . The surface of impregnation catalysts consists of a mixture of nickel oxide and oliromia, while that of coprecipitation catalysts consists mainly of nickel silicate. The results of the -chemi sorption mesurements and the reduction curves showed that the surface of imPregnation catalysts is covered with kactive elements more than that of coprecipi%ation catalysts. The in terrelation for the relation between the amount of the active element and its catalytic activity was tested hydrogenation of acetone. The results showed that the catalytic activity depends on the amount of the active element.

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Particle size effect of supported metal catalysts on oxidation catalysis should be extensively investigated with reference to the optimization of catalyst preparations. This study deals with one of the particle size effects, i. e., "structure sensitivity", of the supported platinum catalysts in the oxidation of propane. While the fresh (untreated) catalysts prepared with FLPtCl6 showed fairly low activities, a remarkable increase of catalytic activity was observed after pretreatments of the catalysts at 750° C in O^2- or 112 stream and at 420° C in the reaction mixture (Table 2, Fig.2). This enhancement may be due to the removal of a small quantity of Cl ion, which remained on the surface of the catalysts during their preparations, from the catalysts. For the catalysts which attained a high level of catalytic activity after the pretreatments, a remarkable particle size effect on propane oxidation was observed in the wide range of platinum particle size from 20 to 2000A, that is, the specific activity (turnover frequency) increased almost proportionally with the increase of the mean particle size (Fig.3). This means that the catalytic activity (rate per unit catalyst weight) for propane oxidation is determined only by the supported amount of platinum regardless of the particle size. This effect was confirmed not to be due to some apparent factors, for example, the rate control by the boundary layer deffusion (Fig.4) or by the micropore diffusion (Table 2), and the increase of effective temperature of the platinum surface. This particle size effect was discussed on the basis of electron transfer from platinum to the supporting materials.

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Although Be+ ion-exchanged zeolite A in hydrated state shows crystalline structure and is stable, its crystal structure disintegrates in terms of heating and dehydration. The reason for the instabilization of its structure is unknown. This paper deals with the investigation of thermal stabilities of (Baex, Na)-A, (Baer, T1)-A, and (Baex, Caex)-A by means of thermal analysis (DTA, TG) and X-ray powder diffraction. It was found that thermal stability of the above compounds is in the order, (Baex, Tlei)-A (Baex, Na)-A (Baex, Caex)-A. All Baex-A zeolites having more ion-exchanged degree than 50% are unstable when including water is removed by heating. The site of Ba"ion was also estimated in terms of X-ray diffraction data of dehydrated samplas.

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Mechanism of CO oxidation over Rh/metal oxide catalysts (Rh/VO^2-, Rh/UO₂, Rh/WO^2-, Rh/ MgWO₄, and Rh/CaWO₄) was studied by means of a pulse reaction method combined with an electromotive force (EMF) measurement.
The activity of each catalyst was propotional to the amount of surface oxygen, but its propotionality constant was different from each other. Its propotionality constant was correlated to EMF change a(4E)10x, related to the removal of oxygen from the catalyst by CO pulse. Furthermore, a(zIE)16x value was correlated to the oxidation activity of the catalyst for CO pulse reaction.
This fact suggested that 8(4E)18x value related to the oxidation ability of the catalyst and would be used for convenience as a measure of its ability.

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Vapor-phase hydrolysis of COS as well as CS, over alumina catalyst xhas been investigated at 230° C with reference to their relative reactivity. The overall relative reactivity, lecosKcos/kcs2. Kosgi where k, and K, are the surface reaction rate constant and the equilibrium adsorption constant for i species (COS or CS), respectively, has been determined to be 6.49 by the initial rate method whereas it to be 7.35 by means of the cohydrolysis of these sulfur compounds. In addition to these, an overall relative reactivity of 6.15 or 29.9 has been 'obtained front the mathematical analysis for the consecutive hydrolysis of CS, to CO, via COS. Since the relative eqUilibrium adsorption constant, Kcos/Kcs2, has been shown to be 2.7 from the inhibition effect of CO, on the hydrolysis reaction, the relative surface reaction rate constant, kcs/ks, , has been estimated to be 2.3-2.7, indicating the higher reactive nature of COS than CS₂; These methods used and the obtained results are discussed. An overall= relative reactivity, : of 6.15-, 4.49 and a relative surface reaction rate constant of 2.3-2.4 are shown to be reasonable values. It is also shown that the reactivity of the sulfur compounds is decisively influenced by the nature of the negatively charged adsorbed molecule as being active species for the surface reaction rather than by that of the free molecule.

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From a viewpoint of electrophotographic applications, fundamental aspects of the photoinjection of charge carriers from a photoconductor into an insulating liquid were studied. Steady state photoinjection currents were measured in a sandwich structure, Au/a-Se or a-As2Sedliquid paraffin/Au, with or without chemical additives in the liquid layer.
The photoinjection current varied linearly against the applied voltage only in a narrow range of experimental conditions, and over that range, the currents showed a superlinear and a sublinear dependences, successively. The log J vs. log V curve changed as a function of the photoconductor, the insulating liquid and the additive used, and also of the polarity of injected carriers. The photoinjection current scarcely depended on the light intensity, and it is independent of the nature and the concentration of additives. Ionizable additives tended to increase photo- and dark-current, injected charges being stabilized and transported by the added molecules. On the other hand, there were some evidences found that the ions produced from additives at the interface region worked to retard the photoinjection by forming a space-charge layer there.

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The extraction of zirconium(IV) from hydrochloric acid solutions with trioctylamine (TOA, R3N) and tricaprylmethylammonium chloride (Aliquat-336, R3R'NCl) in benzene has been investigated under different conditions. In both extraction systems, it is found that the distribution coefficient increases steeply with increasing of initial aqueous hydrochloric acid concentration at 6.0 molg, although Aliquat-336 is more efficient for the extraction of zirconium(1v) than TOA. It is observed that the stoichiometric composition of the organic extracts with TOA and Aliquat-336 are (R3NH)2ZrCl6 and (R3R'N)2ZrCl6, respectively. This is supported by the dependency of distribution coefficient on solvent concentration. Accordingly it is inferred that the extractions of zirconium(1V) from hydrochloric acid solutions with TOA and Aliquat-336 proceed as the following equilidrium reactions, respectively,
ZrCl4(aq) + 2 R3NHCl(0, 0 (R3NH) 2ZrCloorg)
and
ZrCl62-(aq) + 2 RSR'NCI(org) 4t (R3R'N) 2ZrO6(org) + 2 CI-cud
These results are also confirmed by IR and high resolution NMR spectral studies of the organic phases.
Further the effect of diluent on the extraction is surveyed with Aliquat-336. The results show that the extraction is enhanced in 1, 2-dichloroethane and reduced in carbon tetrachloride and xylene.

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The effects of the reaction conditions of the semibatchwise heterogeneous reaction of the system, Ca(OH), -SO^2-(4-6° C), on the shape and size of the particles of resulting CaSO^2-/2H₂0 have been studied. The dissolution rate of the milk of lime influenced not the diameter of a spherical particle, but the smoothness of the particle surface; the surface was smooth for larger dissolution rates (Figs.1, 3). The mean diameter of the spherical particles decreased linearly with decreasing logarithm of circumferential velocity of the stirring impeller at a rate of about 0 x10-6 in the range of log (circumferential velocity) from 281 to 0.719 (Fig.4). The concentration of Ca(OH), and SO₂ had no influence on the spherical particle formation in the range of 20 wt% and 15-100 vol%, respectively (Figs.6, 7). The feeding rate of SO₂ influenced the uniformity of the particle diameter. At a feeding rate of 250 mu min into a 1 liter reactor, the most uniform particle diameter was obtained (Fig.9). Addition of citric acid, citrates and sucrose prevented the formation of spherical particles, producing the new crystals, which were presumably the crystals of CaS0ex H₂0(x1/2).

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Calcium sulfite tetrahydrate was synthesized from milk of lime containing 0.05 wt% sodium citrate and sulfur dioxide by semibatch heterogeneous reaction at 4-6° C. It was obtained as the transparent crystals with particle diameters of 3-60 gm (average diameter: 15 Atm). The chemical composition of the synthesized calcium sulfite tetrahydrate was CaO: 29.7 wt%, SO₂: 32.5 wt% and H₂O: 35.9 wt%. These values agreed well with the calculated values. In the powder X-ray diffraction pattern, the strong diffraction lines were observed at the dvalues(A) of 5.80, 3.64, 2.88 and 2.68 (Table 2). The thermal analysis of the tetrahydrate was carried out by DTA, TG and DSC under the condition of constant heating and cooling rates. The endothermic weight losses of 30.9 and 3.8 wt% were observed at temperature ranges of 30-69 and 363-390° C, respectively (Fig.1). It was considered that the former resulted from vaporization of 7/2 H₂O, and the latter from vaporization of 1/2 H₂O. It was revealed that the change of tetrahydrate to hemihydrate occurred at a temperature range of 34.3-55.5° C and absorbed the heat of about 17 kjimol(CaSO^2-.4 H₂0).

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Low temperature deposition of pyrolytic carbon onto an artifical graphite plate (8 cm in length) from cis-1, 2-dichloroethylene was attempted by the use of a resistance tube furnace placed horizontally. Source material was supplied with argon gas through an inlet nozzle placed at 0.5 cm upstream from the end of a substrate plate. The deposition began at 500° C and proceeded rapidly with the rise of temperature until 700° C. Most of the experiments were carried out 600° C because the nozzle was plugged up with deposited carbon in the experiments above 700° C. The optical microstructures of the pyrolytic carbon were arranged in the order of columnar, dense isotropic, and porous isotropic types along the gas stream. The length of the columnar zone was extended from 1 cm to 8 cm with the increase of a gas flow rate from 35 m//min to 190 m/Jmin. Deposition rates calculated from thicknesses were not uniformly extended over the whole surface of the plate, but had a maximum in the isotropic zone. The position at which the maximum rate was observed was shifted to the downstream with the increase of a gas flow rate. The increase of concentrations of dichloroethylene from 7 vol% to 25 vol% affected the deposition rate more, but the length of the columnar zone and the positions of maximum deposition rate less. The maximum deposition rate was about 150, um/hr and the pyrolytic carbon layer obtained showed a great adhesion to the graphite substrate. The characteristics of the pyrolytic carbon prepared at 600° C were as follows: specific grayity; 1.50, specific resistance; 3.7 x 10-2 ohmm, X-ray parameter ei; 3.88 A, Le; 10 A, content of Cl; 4.3 atomic%.

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An attempt to grow crystals of MgGa2O^2- was made by slow cooling of Pb0-PbF2-132O^2- flux with varying B2O^2- amount, in which MgO and Ga2O^2- were dissolved as solutes. The growth was conducted by heating mixtures at 1200, 1100 or 1000° C for 10 hours followed by cooling to 500° C at a rate of 5° C/hr. Results obtained were summarized as follows:
( 1 ) When the soaking temperature was 1200° C, the optimum composition of mixture to grow the crystal was MgO (12 mol%)-Ga2O^2-(8 mol%)-Pb0(35 mol%)-PbF2(35 mol%)-B2O^2-(10 mol%). Crystals grown in PbO-PbF2 flux containing a proper quantity of B2O^2- were bigger, more colorless and more transparent than those grown in Pb0-PbF2 flux.
( 2 ) When the optimum composition was used, a tendency for the crystal to grow bigger was increased as the soaking temperature was raised.
( 3 ) A maximum weight of the crystal grown in the mixture of 50 g in weight was about 168 mg (about 5 mm in size). The crystals were basically octahedral form with {111} faces, colorless and transparent.
( 4 ) A density of crystals, picnometrically determined, was 5.32 g/cm3. This value was in good agreement with the one reported in a literature.

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A method was described for the simultaneous determination of zinc, cadmium, lead, copper and/or bismuth in bottom sediments of sea and river by square wave anodic stripping voltammetry (SWASV) and differential pulse anodic stripping voltammetry (DPASV) with a hanging mercury drop electrode. Before the determination by ASV a wet mud was digested with a mixture of nitric and hydrochloric acids. An aliquot of acid-digested sample solution was taken and evaporated to near dryness on a hot plate and the residue dissolved in hydrochloric acid. This solution was heated after the addition of hydroxylamine hydrochloride to reduce iron= to iron(II), because iron (III) interfered with the measurement. Stripping curves of zinc, cadmium, lead and copper in this solution were recorded as well defined peaks. The peak potentials were0.93 V for zinc, -0.57 V for cadmium, 0.36 V for lead and - 0.11 V for copper (vs. SCE). The simultaneous determination of the four elements by ASV was accomplished by the standard addition method. The results obtained are in good agreement with those by atomic absorption spectrophotometry. When bismuth contained in sediments, it could also be determined satisfactorily by this method. A peak potential 0. O^2- V (vs. SCE) came out for bismuth.

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A new type of oscillopolarograph (HeyrovskST-Forejt type) with varying frequencies (102000Hz) was designed and constructed. This apparatus was used for the study of the electrode reactions of lead( IC ) complexes with polyamino polycarboxylic acids. Each Cut-in of lead (II) complex with the ligand (nta, edta(OH)2, ttha, edta, dtpa or cydta) appears only in the cathodic process and its Cut-in potential (vs. SCE) was measured accurately. It was found that with decreasing stability constant of complex, the Cut-in height varies sensitively with change in frequency. On the other hand, the Cut-in potential is affected in the case of complex with large stability constant. The rate constant of electrode reaction kg, was determined. The rate constant increases with increasing E pKt(negative logarithm of acid dissociation constant). The value of k: increases with the sequence of the ligands: ntaedta(OH)2cydta dtpaedtattha. In lead(II)-ttha system, the potential of the Cut-in M2 attributable to the reduction of complex for lead(II)-ttha complex does not change with ttha concentration. On the other hand, the Cut-in M2 is remarkably affected by pH. It may be assumed that the number of proton taking part in the electrode process of leadE-ttha complex changes at pH nearly equal to 5. The Cut-in M2 may be due to the reduction of PbH₂L2- at lower pH than 5 and that of PbHL3- at higher pH than 5. As an application, the determination of bismuth (III) in the presence of lead (II) was examined.

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Synergistic effect of 1, 10-phenanthroline(phen) on the extraction of cobalt(II) with dithizone (H₂dz) was investigated and the extraction of cobalt(II) into chloroform was found to proceed according to the following equation:
Co²⁺ 2 H₂dzorg phenorg Co(Hdz)2(Phen)org + 2 H⁺
The resulting reddish adduct had an absorption maximum at around 521 nm, the molar absorptivity being 3.4 1O^2- dm3ol-1m^-1. The effect of 1, 10-phenanthroline on the above extraction was summarized as follows. ( 1 ) The extraction of cobalt (II) with dithizone was accelerated. ( 2 ) Stabilization of the oxidation state of cobalt( II ) in the dithizonato complex and the enhancement of the extractability of cobalt (II) caused by the formation of an adduct were observed. ( 3 ) Masking effect due to the formation of Co(phen)s in the aqueous phase was alSo found.

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Keto-enol tautomerism and solute-solvent H-D exchange of N, N-dimethylacetoacetamide were followed by the change in H-NMR spectra after dissolving it into methanol-d (8.3% (v/v)). The molar ratio of the keto form passed through a minimum before it approached a final equilibrium value, while the degree of deuterium substitution at the methylene group followed an ordinary first order reaction kinetics. A general reaction scheme (Scheme 2), which includes both keto-enol tautomerism and H-D exchange, was simplified by the use of the experimental conditions so that only five intermediate species were involved (Scheme 3). The experimental data were reasonably reproduced by the theoretical calculations (Eqs.13 and 14) based on the simplified reaction scheme (Figs.2 and 3). The keto-enol tautomerism of N, N-dimethylacetoacetamide in methanol was thus concluded to proceed via solute-solvent proton exchange reaction.

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The photosubstitution of the bromine atom at 4-position of 1-acetylamino-4-bromoanthraquinone 3D and 1-acetylamino-2, 4-dibromoanthraquinone [ 5] with butylamine has been studied in ethanol and benzene under visible light irradiation. In the case of 31 the 'CT(S) level is very close in energy to the rot (T) level in both the solvents. Kinetic analysis indicates that the photoamination proceeds via the 'CT (T, ) level after the process S, (1CT) -+ T2(3ne) T, (3CT). The rate constants (kr and kd) of the processes via the 8CT(T, ) level and the rate ratios (krdl kin) via the 3n7r(T2) level are evaluated (Fig.6 and Table 2). In the case of [ 5 ], no photoamination took place because of the absence of CT levels (Table 3).

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5-Phenoxymethy1-2-oxazolidinone (PMO), obtained by the reaction of tris (2, 3-epoxypropyl) isocyanurate (TEPIC) with phenol, gave dimorphic crystals, A- and B-forms, or their mixtures (Fig.1). The composition of the mixture depended upon solvents of recrystallization, grinding conditions and thermal treatment. In solution two forms gave the identical IR and NMR spectra, but in solid phase they showed marked differences in the IR spectra (Fig.2), X-ray diffraction patterns (Fig.3), and DTA curves (Fig.4). The transition temperature from Bto A-form was determined by the methods of microscopy and DTA measurement.
No difference in the pyrolytic behavior was observed in these two forms. The activation. energy and order of the pyrolysis were calculated from the TG curves to be 23.0 kcal/mol and zero, respectively.

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Sodium 2-octyl- (R 8), 2-decyl- (R 10), 2-dodecyl- (R 12), and 2-tetradecyl-(R 14) phenothiazinemonosulfonates were prepared and purified. These samples were identified by elemental and NMR analyses. Studies on the surface active and antimicrobial properties of these samples were carried out.
The experimental results obtained are as follows: 1) Surface activity, such as lowering of surface tension, emulsificability of paraffin into water, and wettability of cotton cloth in aqueous solutions, increased with increasing in alkyl chain length.2) The antimicrobial property of R 14 is excellent and comparable to those of commercial agents.

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Effects of cationic, anionic, and nonionic surfactants on the coupling rate have been investigated kinetically. It has been found that micellar effects are affected by the formal charge of both reactants, i. e., diazonium ion and substrate. For example, the reaction of m-chlorobenzenediazonium ion with N, N-bis(2-hydroxyethyl)aniline was considerably accelerated by anionic surfactants such as sodium dodecyl sulfate, sodium alkylbenzenesulfonate, and sodium laurate. In the reaction of diazoniobenzene-4-sulfonic acid with it, however, no pronounced micellar effects have been observed. Whereas the reaction of diazoniobenzene-2, 5-disulfonic acid, bearing net formal charge of with it, was accelerated by cationic surfactant.
The influence of formal charge of reactant on micellar effect has also been investigated by using 1-naphthylamine-4-sulfonic acid as a substrate. The results obtained have been interpreted in terms of electrostatic interaction between micelles and reactants.

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1, 1-Difluoroethylene (VF 2) was obtained by the gas phase pyrolysis of chlorodifluoromethane (CHClF2) with propene (C3H6) or ethylene (C_2CH4). The reaction was carried out by a flow method under atmospheric pressure. The reactants (molar ratios of C31-16 to CHClF2: 0.133.0 and C_2C1-14 to CHClF2: 0.9-30.0) were introduced into a spherical reactor in the temperature range 720900° C in the presence of steam. Residence time was varied between 0. O^2- and 0.52 sec.
Major products in this reaction were VF 2 (3-40% yield based on CHClF2) and tetrafluoroethylene. The yields were dependent on the molar ratio of the reactants and the conversion of CHClF2. Formation of VF 2 was disturbed by the carbonaceous products formed on the reactor wall. The space-time yield of VF 2 amounted to 14.6 molgr. A linear relationship was obtained in the plots of logarithm of the maximum value of the space-time yield of VF 2 at a given temperature vs. the reciprocal of pyrolysis temperature. There was little difference in reactivity between C31-1, and C_2CH4.

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For the purpose of preparing useful chelating resins from poly (glycidyl methacrylate) beads, the influence of pore structure of the polymer beads on the adsorption of copper( II ) ion was 'investigated.
Chelating anion exchange resins were prepared by amination of the polymer beads with triethylenetetramine. The amination was carried out easily. The chelating resins obtained from gel type polymer beads did not have good adsorption ability for copper(II) ion. It was found that the satisfactory chelating resins were prepared by the amination of macroreticular polymer beads which were obtained by suspension polymerization of glycidyl methacrylate in the presence of 2, 2, 4-trimethylpentane (50 vol% per monomer). The chelating resins obtained were moderately resistant against acid and alkali.

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In the previous investigation, it was found that the macroreticular polymer beads of glycidyl methacrylate are favorable for the preparation of chelating resins.
In this study, the introduction of mercapto groups into the macroreticular poly (glycidyl methacrylate) beads was investigated by the following two methods. ( 1 ) By the reaction of polymer beads with a dioxane solution of mercaptoacetic acid, favorable chelating resins (RGS-TGA) containing 9-10 wt% sulfur could be prepared. ( 2 ) By the reaction of polymer beads with a methanol solution of ammonium thiocyanate, followed by the reaction of these products with ethanolic potassium hydrogensulfide, favorable chelating resins (RGS-KSH) containing 17-18 wt% sulfur were obtained.
The chelating resins obtained by the two methods had good resistance against air oxidation and showed the selective adsorption ability for Au3+, Ag+ and Hg²⁺ in a lower pH region.

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For the purpose of recovery of mercury (II) from aqueous sulfuric acid solution, the adsorption behavior of mercury (II) on some chelating resins was tested by batch and column methods. A macroreticular chelating resin (RMH) containing hydrazide groups turned out useful for the purpose. In the batch method, adsorption ability for mercury (II) of RMH in aqueous sulfuric acid decreased with increasing acid concentration. Even from a 60% sulfuric acid solution, RMH showed a good affinity for mercury (II). However, mercury (II) does not favor the resin to any great extent from 2 N hydrochloric acid medium. In the column method, RMH exhibited a satisfactory adsorption ability for mercury (II) under the following conditions: loading solution, Hg(II) 2000 rng/l, sulfuric acid 20%, space velocity 6/hr. When potassium permanganate contained in the loading solution, the permanganate should be reduced with 10% hydrogen peroxide solution before the solution was passed through the column. The elution of mercury (II) adsorbed was accomplished by allowing 12 N hydrochloric acid to pass down the column. The recycle of adsorption and elution was found to be satisfactory.

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ZrN whiskers are grown on various substrates. It is found that Ni, SiO, and mullite substrates are effective in whisker density and in growth rate for the growth from a ZrCl4-H₂-N, system. The presence of Si-carrying species in a vapor phase also accelerates the nucleation of whiskers. ZrN whiskers grow at the temperature range of 1000-1300°C and in the direction of (100) and (111).

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To prepare pyrazolone-series monomeric azo dyes containing polymerizable group in the coupling com. ponent, 3-methyl-l-[p-(methacrylamido)phenyl]-2-pyrazolin-5-one C as the coupling agent has been synthesized. Then 4-arylazo derivatives [5] were prepared by the coupling reaction of [1] with aromatic diazonium salts in which the aromatic moieties are C6115, p-CH₃C6H4, m-CH₃C6H4, p-CH₃OC6H4, m-CF-130C6H4, p-ClC8H4, m-ClC8H4, P-NO₂C6114, m-NO₂C61-14 and P-(CH₃)2NC6H4. Tautomerism in [1] and [5] was investigated by IR and NMR spectra.

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