The isomerization of diethyl maleate (A) to diethyl furnarate (B) over a CaO. catalyst suspended in heptane proceeds rapidly in the initial stage but very, slowly in the latter stage. Original basic sites [s]e on the CaO surface mainly promote the reaction in the initial stage, in which the adsorption of A onto [S] limits the reaction rate. A strong adsorption of the product (B) results in a decrease in the surface concentration of [S]e and, when the adsOrption, reaches, the saturation, the initial stage finishes. Only weak basic sites [B_**S]c promote the reaction in the latter. stage, in which the adsorption of A onto. [B_**S]Q limits the rate. The rate of the latter stage obeys the zero-th order kinetics. These characteristic features of the reaction are observed in every one of the other solvents including pentane, hexane, and octane. Furthermore the rate of the latter stage is little affected by the viscosity of the solvent.
In the range between 0 and 150 11413ath e increase in pressure results in a decrease in the reaction rate of the 'latter stage; the experimental activation volume ΔV_exp, is 20±2ml·mol^-1(in heptane). The positive activation volume is explained in terms of a desolvation caused by the formation of transition state with a highly dispersed ionic charge:, A linear relationship between the apparent activation volume and the molar volume of solvent is utilized to estimate the intrinsic activation volume for adsorption ΔV_ads; The negative value of ΔV_ads(-21ml·mol^-1) well conforms to the physical picture of adsorption.

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For the characterization of carrier's role on the catalytic activity of highly dispersed Ni catalysts supported by alumina, silica-alumina, kaolin, acid clay, kieselguhr and silica, magnetic measurements, chemisorption studies with hydrogen and ethylene, X-ray diffraction, differential thermal analysis and X-ray microanalysis have been made (Ni-SiO₂) was the same as that used in the previous studies. Surface areas, average particle sizes and degree of dispersion of Ni crystallites are shown in Table 1.
Magnetisations obtained at different temperatures were superimposed in the plots of magnetisations versus HIT except for the catalyst [5]and [7] in Table 1, in which the latter showed a limit of the average of the size of crystallites showing superparamagnetism. Our previous studies showed that Ni crystallites accepting adsorbates were not uniformly distributed and finer particles of the Ni crystallites have a hydrogen adsorption corresponding to the first stage of magnetisation isotherm, while the larger crystallites have the adsorption corresponding to the second stage. Hydrogen adsorption for the first stage was estimated to be 0-11 ml/g·Ni for the catalyst [6]-[9], while it had been estimated to be about 18 ml/g·Ni for Ni-SiO₂. Migration of adsorbed hydrogen atoms away from the metal and onto the supports was believed to occur on the catalyst [5], [8] and [9] at 100°C.
The number of bonds formed by each metal atom was estimated. In the case of C₂H₄there was magnetic evidence for a bond number of about 4, corresponding, for instance, to the presence of the surface species NiCH=CHNi and two hydrogen atoms adsorbed on the adjacent sites. It seems that dimerization proceeded for C₂H₄ contacted with the bare surfaces of the catalyst [6], [8] and [9] at 15°C and the possibility for occurrence of hydrogenation of C₂H₄ was found in the magnetisation measurements when C₂H₄ adsorbed on an H₂ covered surface and vice versa. The nature and distribution of supports and the degree of dispersion of Ni, that is 0.2 for Ni-SiO₂ and O.05-0.12 for the other catalysts, may have influence on these reaction processes. Surface distribution measurements of Ni, Si and Al before and after reduction revealed the dispersion properties of these elements.

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A study was made of the electrode behavior of the silver-silver oxide electrode in 4.7 mol/l KOH electrolyte containing potassium sulfite and palladium chloride. The influence of these metallic salts was examined by potentiostatic and galvanostatic methods, as well as an observation under the scanning electron microscope.
The following results were obtained:
1) The capacity of the electrode increased up to about 160% by the addition of potassium sulfite at a normal discharging rate, and up to about 200-225% by the addition of palladium chloride at a high discharging rate. But the capacity decreased by the addition of palladium chloride at a normal discharging rate.
2) The coulombic areas under all the peaks in cyclic voltammograms became larger by the addition of potassium sulfite or palladium chloride. From these facts, it is generally accepted that an active mass of the electrode is greater than that present in the non-addition case.
3) The capacities of the electrodes in charge-discharge curves and current-potential curves increased with these additives. According to electron-microphotographic observation, this seems to be due to the formation of fine grained crystals of active material caused either by the adsorption of ionized particle: produced from the added potassium sulfite, or by the adsorption and electrolytic deposition in the case of palladium chloride.

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The reaction between ZrP₂O₇ and CaCO3 in the solid state has been studied for the compressed mixtures of various concentrations ranging from 1O to 9O mol% CaCO₃. All the mixtures were heated at 13OO°C for 24 h in air. The samples containing 5O mol% CaCO₃ were also heated at elevated temperatures up to 14OO°C for 2 h. After the reactions had completed, the samples were quenched to room temperature and subjected to X-ray powder diffractometry. The reactions between ZrP2O7 and CaCO3 yielded the following compounds; CaZr₄(PO₄), CaZr(PO₄)₂, Ca₃(PO₄)₂ (a and 19 phase), ZrO₂(monoclinic and tetragonal) and CaZrO₃. The compound CaZr(PO₄)₄ was isolated from the reactant of the mixture containing 65 mol%CaCO₃. X-ray diffraction pattern of CaZr(PO₄)₄ was different from that reported by Bettinli et al. The compound CaZr₄(PO₄)₆ was formed in the range from O to 65 mol% CaCO3 and CaZr(PO₄)₂ in the range from 33.3 to 75 mol% CaCO3 upon the solid state reaction. In the sample containing 5O mol% CaCO₃, CaZr₄(PO₄)₆ and CaZr(PO₄)₂ were formed on heating at elevated temperatures up to 135O°C. The latter, however, decomposed to CaZr₄(PO₄)₅ and a liquid phase of CaO-P₂O₄ system above 135O°C.

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Red mud was treated in acid solution under various conditions; varying temperatures, time intervals and acid concentrations, and the effect of these parameters on solubility of the coponents of red mud were observed (Fig.1). It was estimated that the mud contained some stable aluminosilicates such as kaolin, which were insoluble in fairly concentrated hydrochloric acid at room temperature. A discussion on the principal constituents of red mud was given, based on X-ray diffraction patterns (Fig.2).
The exclusion of titanium in red mud was tried by adding hydrogen peroxide in cold the solution, and the resultant product from red mud contained titanium dioxide as low as 3%, ` while iron(III) oxide content increased to 83%.
Separation of constituents of red mud was achieved in the following way. Gentle heating with concentrated sulfuric acid was first applied to dissolve all the components except silica, and then, fractional precipitation of the components was carried out by hydrolysis after the partial neutralization with ammonia, at either presence or absence of some reducing agent (Fig.3 and Table 7). t Studies on the Method of Treatment of Red Mud. II.

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The leaching reactions of manganese nodule(CM-16) with ammonium sulfite solution have investigated putting particular emphasis on the effects of temperature, ammonium concentration, and particle size of the nodules. leaching proceeded through the following simultaneous reactions. MnO₂ + 3 (NH₄)2SO₃ + 2 H₂O =(NH₄)2Mn(SO₈)2. H₂O (NH₄)2SO₄ + 2 NH₄OH MnO₂ + 4 (NH₄)2SO₃ + 3 H₂O =(NH₄)2Mn(SO₃)₂. H₂O (NH₄)2S₂O₆ + 4 NH₄OH Copper, nickel, and cobalt were extracted simultaneously in the forms of metal ammine complex from their metal oxides, which are dispersed in the manganese nodule. The leaching rate from fine nodule was expressed as a function of the reduction ratio of manganese (N)oxide(x), or the leaching ratios of nickel and cobalt(x_N1 x_co) as follows:
-1n(1-Xi)-Xi=Kt·C₂·t
i:Mn, Ni, Co
Kt: Apparent rate const., C: Ammonium sulfite concn., t: Duration of leaching.
The activation energy was 117 kJ/mol. The effect of particle size on the leaching rate was analyzed considering the pore diffusion of ammonium sulfite. The effective diffusion constant was estimated to be 6.2 x1O-8cm²/s. In the IR spectrum of manganese(ff) ammonium sulfite monohydrate, the characteristic doublet for the double salts of ammomium sulfite, NH bending mode of NH₄+ appeared in the 15OO∼-125O cm^-1 region. Ammonium dithionate decomposes to sulfur dioxide and ammonium sulfate at 176°C.

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The cobalt[II] complexes of two types, CoL₂ 2H₂O([1a]∼[11a]) and CoL₂([1 b]∼[11b]), were synthesized with 1-(p-substituted phenyl)-1, 3-butanediones (HL, L =p-XC₆H₄COCH COCH₃, X=NO₂[1], COOH[2], COOCH₃, [3], Br [4], Cl[5], H[6], NHCOCH₃[7], C₂H₅[8], CH₈[9], OCH₃[10], OH[11]), and their configurations were investigated by the measurements of magnetic moment and electronic spectra in the visible and ultraviolet regions. It was found that [1a]∼[11a]were monomeric octahedral in benzene, chloroform, pyridine and DMSO as well as in solid state. [1b]∼[11b]were tetrahedral in DMSO, but they changed their configurations to octahedral by the coordination of two solvent molecules in pyridine. These anhydrides except for [7b]were trimeric octahedral in solid state or in chloroform. Since the absorption bands of v, and v3 observed in the UV-visible spectra of octahedral complexes and of v2 observed for the tetrahedral complexes shifted linearly to the higher frequency side as the substituents became more electron donative, the stability of these complexes was found to increase in the order of [1]<[2]<[3]<[4]<[5]<[6]=[7]<[8]<[9]<[10]<[11]. The crystal field splitting energy 10 Dq and the electron repulsion parameter B were calculated from the p values of the →d transitions.

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The reaction of nitrobenzene with a mixed ligand complex of cobalt(II) with cyanide ion and ethylenediamine(en) at 30°C in the absence of oxygen produced azoxybenzene selectively. Under a nitrogen atmosphere the yield was better than under a hydrogen atmosphere, so that. subsequent experiments were carried out under a nitrogen atmosphere. The yield was maximum when the molar ratio of Co/CN/en was 1: 3: 1. The existence of the complex of this compostion was confirmed by the measurements of conductivity and absorption spectra. The reaction mechanism was discussed.

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2-Thioxo-5-nitroso-1, 3-diethylperhydropyrimidine-4, 6-dione(TNEP) has been examined as a reagent for the spectrophotometric determination of iron(II). The ironaD-TNEP complex has the molar absorptivity of 2.24 x10⁴ /·cm^-1·mol^-1 at 650 nm in aqueous solution. Absorbance of the complex is constant over the pH range from 5.0 to 6.8. A large amount of cobalta(II), copper (II) and nickela(II) interferes, but can be masked by the addition of a pH 10.3 buffer solution. The other common ions do not interfere. The ratio of metal to TNEP in the complex is 1: 3 according to the continuous variation method. The irona(II)-TNEP complex, Fe(C₈H₁₀N₃O₃S)3·3H₂O, has also been isolated. The procedure for determination of iron is as follows.1) Non extractive method. Place a sample solution into a 10 ml volumetric flask, and add 1 ml of acetate buffer solution(pH 5.5) and 3 ml of an ethanolic TNEP solution. Dilute to the mark with water. Measure the absorbance at 650 nm against the reagent blank.2) Extraction method. Into a 30 ml separatory funnel, take 5 ml of, a test solution, 4 ml of acetate buffer solution (pH 5.5) and 5 ml of the TNEP solution. Shake the mixture with 5 m/ of isopentyl alcohol for 30 s (If a large amount of cobaltaa copper (II) and nickela) coexists, add 3 ml of ammonium chlorideammonia buffer solution (pH 10.3). Measure the absorbance of the organic phase at 640 nm against a reagent blank. Iron in aluminium alloys and die casting zinc alloy or magnesium base alloy can be determined accurately and rapidly by this procedure.

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Effect on conductivity of a polymer fixed with a conducting compound, containing 2-hydroxyethylamino group, in side chains as a part of a polymer composition (chemical dispersion)was compared with that of a polymer simply mixed with it as a dispersion (physical dispersion). Poly(methyl methacrylate) or polyamide-6 was used as a matrix. Concentrations of conducting compound to yield good conductivity in each matrix system were 96.0mol% (97.2 wt%) and 52.0 mol% (60.1 wt%) for chemical dispersion, and 6.7 mol% (9.6 wt%)and 0.6 mol% (0.7 wt%) for physical dispersion. The fact that physical dispersion was effective by the addition of minute amount of a conducting compound would be due to the formation of continuous layer of additives in a matrix.

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The polymerization of isobutyl vinly ether (IBVE) initiated by carbon black surface was investigated. When the polymerization of IBVE was carried out in the absence of carbon black, no polymerization could be detected. In the presence of acidic -color channel black such as Carbolac 1, Neospectra II, or FW 200, the polymerization of IBVE was initiated even at below room temperature. The apparent activation energy of the polymerization was 15kcal/mol. The polymerization was inhibited by pyridine and N, N-dimethylformamide, which indicates that this is a reaction of cationic nature. The rate of polymerization was of the second-order with respect to the amount of carbon black and of the first-order with respect to the monomer concentration up to ca.2.5 mol/l above this concentration it became independent of the concentration of IBVE. The above results were explained in terms of a conventional cationic mechanism. On the other hand, furnace black such as Philblack 0 which contains few carboxyl groups was unable to initiate the polymerization. Upon treatment with diazornethane and sodium hydrogen carbonate, Carbolac 1 lost the ability to initiate the polymerization. On the basis of these results, it was suggested that acidic sites, especially carboxyl groups, on the surface of color channel black play an important role in the initiation of the polymerization.

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The polymerizations of methyl methacrylate (MMA), styrene, and acrylamide were carried out in the presence of CC!, and water, by using the complex DAC-Cu(II) or DAC-Fe(III)perpared from “diaminocellulose” (DAC) and Cu(NO₃₂) or Fe(NO₃)₃, respectively. It was found that the polymerization was especially rapid in the present polymerization system of MMA(6 ml) by using the complex DAC-Cu (II) 50 mg which contained 0.05 mmol of Cu (10) in the presence of 29 ml of water and 1 ml of CCl₄, and the more the amounts of chelating Cu(II) ion and NH₂ group in the complex, the higher became the catalytic activity of this complex. As a result of a Kinetic study of the polymerization, the following rate equation of polymerization was obtained.
R_p=const. [DAC-Cu(II)]^0.5·[MMA]^1.0
In addition, the apparent overall activation energy of the present polymerization system 0.5was estimated to be 11.7 kcal/mol.

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For the purpose to establish a combustion method for low NO_x-formation, in noncatalytic oxidation of NH₃ with O₂ under coexistence of highly concentrated H_xO, CO and H_x, the relations among gas composition, temperature, residence time, fractional oxidation of NH3, fractional formation of NO, and the reaction mechanism were investigated. The experiments were carried out by using a flow reactor, under an atmospheric pressure and at 6OO-195O°C (mainly.85O°C). The inlet gas composition was O-15OO ppm NH₈-O-2O%CO-O--57OH₂-O-3%O2-O-1O%H2O-N₂ and the residence time was O.19-1.45 Ns (mainly O.37 Ns).
The main results obtained are as follows:
1) A Chain reaction mechanism where OH radical was a main carrier was discussed as follows: since the oxidation of CO and H₂(CO+O₂→CO₂+O, O+H₂O→2OH, CO+OH→ CO₂+H, H₂+O→OH+H, H₂+OH→H₂O+H) occurred at a low temperature, the oxidation of NH3 with O and OH radicals(NH₃→NH₂→NH) and consequently the reactions of NH+O₂→NO+OH and NH+NO→-N₂+OH occurred more or less according to the reaction conditions.
2) At a combustion under a lack of O₂, the performance of NIL-oxidation played an important role. The optimum air ratio(mole ratio of O₂ to fuel) was required to make the fractional denitrifican (removal of NI-18 minus formation of NO) maximum in NIL-oxidation. The lower the temperature, the shorter the residence time, the lower the more ratio of CO/H₂, the higher the total concentration of CO plus H₂, and the higher the concentration of NH₃ and H₂O, the higher became the opimum air ratio.

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For the purpose to establish a new combustion method to reduce NOs-formation, by NH₃, without catalyst and under coexistence of highly concentrated H₂0, CO and H₂, the relations among gas composition, temperature, residence time, fractional reduction of NO, fractional oxidation of NH₃, and the reaction mechanism were investigated. The experiments were carried out by using a flow reactor under an atmospheric pressure and at 600-1050°C (mainly 850°C). The inlet gas composition was 0-750 ppm NO-500-1500 ppm NH₃-0-20%C0-0-5%112-0-3%O₂-0-10%H₂O-N₂ and the residence time was 0.19-1.45 Ns(mainly 0.37 Ns).
The main results obtained are as follows:
1) The optimum air iatios were necessary to make the fractional reduction of NO and the fractional denitrification (the removal of both NO and NH₃) highest. The higher the concentration of CO+H₂, H₂ and, H₂0, the lower the temperature and, the shorter the residence time, the higher became the optimum air ratio.
2) When OH radical was a main carrier, the chain reaction mechanism was discussed as follows:
Since under coexistence of CO, H₂0, and a small amount of O₂, the oxidation of CO(CO +O₂→CO₂+O, H₂O+O→2 OH, CO+OH→CO₂+H, H+O₂→OH+O and H₂O+H H₂+OH) occurred at a low temperature, the oxidation of NH₃ with O, OH, and H radicals (NH₃→HN₂→NH) and consequently the reduction of NO(NO+NH→N₂+OH) occurred at 650-700°C. Also, under coexistence of H₂, the reduction of NO occurred from ca.600°C. The reduction mechanism was the same as that of the above case.

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The disproportionation of mercury(I) ion into mercury(II) ion and mercury(0) was studied in a highly dilute mercury(I) perchlorate solution with concentrations ranging from 10^-7 to 10^-8molg. The equilibrium constant, [Hg²⁺][Hg]/[Hg₂²⁺], for the disproportionation reaction was determined by using both a disproportionation equation derived by the authors and the gas-aqueous distribution equilibrium of mercury(0) formed by the disproportionation of mercury(I) ions, which was measured by a cold-vapor atomic absorption spectrophotometer. The equilibrium constant was found to be (3.0±0.2)×10^-9mol/l at the ionic strength below μ=0.1 at 25°C. The mercury(0) distribution ratio, [Hg]_gas/[Hg]_aq, under the gas-aqueous distribution equilibrium conditions was found to be O.40+0.02 at 25°C.

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Amphoteric latices with carboxyl and amino surface groups were synthesized with a water soluble, cationic initiator, 2, 2'-azobis(2-amidinopropane) hydrochloride. The electrochemical nature of the surface of the latices was studied with conductometric and potentiometric titrations. Clear inflections were found on the conductometric titration curves at their points of zero charge. The inflection was explained as a point where a change in surface charge from desorption to adsorption of counter ions occured. The surface charge density of the latices obtained from the conductometric titrations was less than that obtained from, potentiometric titrations. It was concluded that the accurate surface charge density of an amphoteric latex can be obtained from potentiometric titrations rather than conductometric titrations.

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Self-association of phthalimide in dioxane lioscopic measurements. Trimer is formed 2.17 at 11.8°C and 2.41 at 101.4°C. From (Gibbs free energy), ΔS (entropy change)-reaction were calculated. solution has been studied by cryoscopic and ebulin the solution, its association constants being these data, thermodynamic quanties such as ΔG and ΔH (enthalpy change) for this association reaction were calculated .

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The catalytic hydrogenation of chalcones with pentacyanocobaltate(II) afforded r-2-benzoyl, t-3, c-4-triphenylcyclopentanols, dimeric products from chalcones. The use of 50% aqueous t-butyl alcohol as a solvent and the addition of potassium hydroxide resulted in the increase of the dimeric product yields. The replacement of hydrogen at 4-position of chalcone with chlorine increased the yield of the corresponding dimeric product whereas the methoxy groupe at 4- or 4'-position of chalcone entirely suppressed the reaction.

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The oxidation of (trifluoromethy) naphthalene s[1] with CrO₃ in acetic acid has been eicamined for the synthesis of (trifluoromethyl)phthalic acids [2]. (Trifluoromethyl) naphthalenes generally nuderwent cleavage of the ring having no trifluoromethyl group, and the resulting (trifluoromethyl) phthalic acids were isolated in 14-63% yield from naphthalenes: 1-CF₃, 2-CF₃-C₁₀H₇, 1-CF₃-4-F-, 1-CF₃-4-F-, 1-CF₃-2-F-, 8-CF1-CF₃-2-F-, 1-CF₃-4-CL-, 1-CF1-CF₃-4-NO₂, 2-CF₃-1-NO₂-and 1-CFC-2-OCH₃-CCF₁₀HCF₆. However, 4-methoxy-1-(trifluoromethyl)-naphthalene gave 3-(trifluoromethyl)phthalide [3] together with 3-(trifluoromethyl)-3-1-xydroxyphthalide [4], and 5-nitro-1-(trifluoromthyl)-naphthalene remaind intact under these conditions.

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