The surface magnetic anisotropy of the non-stoichiometric iron oxide powders treated with sodium metaphosphate, (NaPO₃)_n, was investigated. In the treated iron oxide powders, anomalous increase in the coercive force and the decrease in the magnetization which was inversely proportional to the coercive force were observed. The maximum coercive force was obtained at a mole ratio of 1.7 (NaPO₃/iron oxide). The coercive force and magnetization of the treated iron oxide powders were restored to the original values after the removal of the coating material by washing with water.
The peak value shown in Fig.3 suggests that the increase in the coercive force neither depends on the decrease in the particle interaction nor on the increase in the magnetostriction of the particle. It might be possible that a large increase in the surface magnetic anisotropy of a particle is caused by a bonding between phosphorous and iron via oxygen ion.

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Crude carbazole (C₁₂H₉N), extracted from coal--tar pitch, contains a small amount of impurities having very similar lattice constants to those of carbazole. In order to remove these im purities, crude carbazole (10 g) was heated with boiling maleic anhydride (20 g) and chloranil (1g) in, 2, 4-trichlorobenzene (30 ml). Next, it was treated with metallic sodium in isopentyl alcohol, subTlhimated, passed through alumina column, and refined by zone melting.
The fluorescence spectra and the wavelength dependence of fluorescence life -time of the evaporated thin film of carbazole were measured in order to detect the impurities. The fluorescen ce maxima of the highly pure carbazole were at 345, 358 and 370 nm at room temperature, and at 345, 351, 370 and 392 nm at liquid nitrogen temperature. The fluorescence maxima of imp u re carabazole were observed not only in the region of 330-400 nm but also in the region s less than 330 nm and more than 400 nm.
On the other hand, the average fluorescence life-time of the evaporated thin film of the ghly pure carbazole was from 18.1 to 21.0 nsec in the region of 345-417 nm at room temperature, and the wavelength dependence was small. The life-time of the impure carba zole was from 7.3 to 22.0 n sec, and the wavelength dependence was large.

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The changes which occur on heating Zn ferrous ferrites have been studied by means of DTA, TGA, X-ray difiractometry and chemical analysis. It is shown that the low temperature oxidation involves no phase change but that hematite precipitates at high temperatures. The increase in ferrite concentration decreases the rate of oxidation. The precipitation is characterized by an apparent incubation period and precipitation isotherms are expressed by the modified first-order equation, log(1 α) =- k (t-t₀), where α, t and k are fractional precipitation, time and proportionality constant which depends on temperature, respectively. The activation energy of this process is 30.0±0.5 kcal/mol irrespective of the ferrite compostion. Substitution of Ni for Zn decreases the rate of hematite precipitation, which has been successfully explained in terms of the cation distribution in spinel lattice.

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The interfacial electrical effects on the detergency, which were calculated from the DLVO theory have been compared with those from the heterocoagulation theory, and they were discussed in terms of the detergency toward soiled cloth or of the soil redeposition toward cloth. In particular, the difference between V_T, _max and V_T, _max/ΔV_T appeared in each theory, which is an important factor in detergency process, has been studied.
The relation between V_T, _max and V_T, _max/ΔV_T obtained from the DLVO theory differs from that obtained the heterocoagulation theory (Fig.1). The detergency toward carbon soiled cotton does not relate to V_T, _max and V_T, _max/ΔV_T obtained from either zeta ( ζ ) potential of cloth or soil particle derived from the DLVO theory. While, the detergency relates to V_T, _max/ΔV_T obtained from both ζ-potentials derived from the heterocoagulation theory (Fig. 2) . The detergency toward mud soiled cotton or the mud soil redeposition toward cotton cloth can also be interpreted in terms of the interfacial electrical effects obtained from the heterocoagulation theory (Table 2, Fig. 3 and 4) . The interfacial electrical effects can be calculated from the DLVO theory by using a geometrical mean of both ζ-potentials Despite the values of, Vcoc, are the same, the relation between V_T, _max/ΔV_T and V_T, _max changes with the ratio of ζ₂ to ζ₁ and the above change is significant in the ratio from 1. 0 to 1. 5 (Fig. 5). In conclusion, the role of interfacial electrical effects on the detergency can be interpreted more exactly in terms of the heterocoagulation theory than the DLVO theory.

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Light scattering measurements were carried out for the mixed aqueous solutions of bovine serum albumin (BSA) and chondroitinsulfate (Chs) at various mixing ratios and at various sodium chloride concentrations. The values of the molecular vcieikkit and of the molecular dimensions decreased remarkably with the increase in the ionic strength. At the infinite con centration of NaCl, the molecular weight approached the value expected when there is no interaction between them. At the finite concentration of NaCl, bowever; it was seen that a complex is formed between them. When the soluble complex was formed, a relation between the number of the BSA molecules bound to one Chs molecule arid the amount of excess BSA existing free in the solution was expressed by a Langmuir-type equation. Thee number of the bound BSA molecules per Chs molecule were 20.6, 11.5 and 5.02, when the concentrations of sodium chloride (mol/l) were 0.0 1, 0.0 25 and 0.0 5, respectively. The constant expressing the strength of the binding in a Langmuir equation k decreased remarkably with the increase in the sodium chloride concentration. It is concluded from these results that BSA molecule would mainly bind to the Chs molecule by the electrostatic force.

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We reported previously an anomaly that the heat of hydrogen adsorption on palladium increased showing a peak at a certain ratio of H to Pd. In this paper, the origin of this anomaly (peaks in Figs.1-3) was studied. Measurement of the X-ray diffraction revealed that there was no correspondence between these peaks and the α → β phase transition of Pd-H₂ system. The peak appeared only in the region of β phase (Fig.3), irrespective of the species of supporting material of Pd (Figs.1-3). The height of the peak decreased with the decrease in the temperature (Fig.4). When the specific surface area of palladium increased, the atomic ratio of hydrogen adsorbed to palladium at the peak increased and the equilibrium pressure of hydrogen decreased (Fig.6). The effects of the pretreatment of palladium by hydrogen (Figs. 7, 8) and the pretreatment by carbon monoxide, as well as the adsorption of hydrogen on the highly dispersed palladium (Fig.9)indicated that the heat of strong adsorption of hydrogen on the surface of palladium was not the origin of the peak. The peak probab ly resulted from the direct dissolution of hydrogen into β phase.

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Photoreduction of aqueous ammonium dichromate solution in the presence of ethanol or 2-propanol was found to be sensitized spectrally by Methylene Blue (MB) over its absorption region at about 700 nm. Efficiency of sensitized photoreduction of Cr(VI) was extremely increased by addition of diammonium ethylene diamine-N, N, N', N'-tetraacetate ((NH₄)₂H₂ edta)in the system. It was confirmed experimentally in the unaerobic condition that the Leuco methylene Blue (LMB) produced photochemically from MB reduces Cr(VI) to Cr(III) and it returns simultaneously to MB.
Supperadditivity was obs erved on the efficiencies of LMB formation and of MB-sensitized photoreduction of Cr(VI) in the system containing both ethanol (or 2-propanol) and (NH₄)₂H₂edta. It was concluded from the experimental results that the rate of the MB-sensitized photoreduction of Cr(VI) is of zeroth order with respect to the Cr(VI) concentration, and it depends on the intensity of light absorption of MB and on the kind and concentration of reducing agents.
A photo reduction scheme which well satisfied the experimental results was proposed.

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As a part of studies on spectrally sensitized photoreduction of aqueous ammonium dichromate solution in the presence of EtOH or diammonium ethylenediamine-N, N, N', N' -tetraacetate ((NH₄)₂H₂edta) as a reducing agent and Methylene Blue as a sensitizer, the pH de pendence of the rates and quantum yields of the photoreduction was measured in the pH range of 3.50-11.60. The rate of photoreduction increased with pH value in the range of pH 3-10, but the photoreduction did not occur when pH was higher than 11. While hydrogen chromate ion (HCrO₂^-) was the only active species of the photoreduction in the intrinsic absorption region. of Cr ( AT), chromate ion(CrO₄^2-) was also reduced in the case of spectrally sensitized photore duction.
The spectrally sensitized photoreduction process under photostationary conditons was considered to be a simple oxidation-reduction system consisted of two redox couples of Cr(VI) -Cr (III)and Methylenene Blue-Leucomethylene Blue.
Quantum yields of the spectrally sensi tized photoreduction of Cr (VI) to Cr(III) were about 10^-3-10^-2 at 650 nm ((NH₄)₂Cr₂O₇: 5X 10^-5 mol/l, Methylene Blue: 1 x 10^-4 mol/l, EtOH: 3 mol/l or (NH₄)₂H₂edta: 1 x 10^-2 mol/l, under N₂ atmosphere at 25°C).

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A new zone-refining apparatus suitable for the purification of inorganic salts with relatively lo\v melting points has been developed. This apparatus has a feature of high speed c lockwise and anticlockwise alternate rotations (0-4000 rpm) with short period (0.5-10 sec). With this apparatus some investigations were carried out to remove 3 d transition metal impurities, especially chromium, in alkali nitrates which are now essential raw materials of multicomponent glasses for optical communications. Chromium forms chromate in. fused alkali nitrates and is dissolved abundantly into them.
The effect of essential fa ctors such as zone travel rate, rotating velocity of the container and alternating period on effective distribution coefficient of chromium (k) is discussed. In conclusion, k decreased by the decrease of the zone travel rate and th e alternating period improving the purification efficiency. Although k decreased abruptly as the rotating velocity increased up to 500 rpm, it then kept almost constant up to 3000 rpm. The reversed rotation of the container on zone-refining is far more effective than stationary upward movement or unidirectional rotation. It is also effective to decrease the alternating period than to increase the rotating velocity to promote zone-refining efficiency. Under the optimum conditions, the k value in the NaNO₃-Na₂CrO₄ system and that in the NaNO₃-Na₂CrO₄ were of the order of 10^-3-10^-2 and this fact suggested the usefulness of this technique for the purifica tion of some inorganic salts.

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Thermal behavior of hydrous stannic dioxide prepared by several methods has been investi gated by means of thermal analysis, X-ray diffraction, infrared spectroscopy and surface area measurement.
This hydrous stannic dioxide is a hydrogel consisting of a framework formed with the aggregation of ultrafine and spongy stannic dioxide containing water. This hydrogel also contains a small amount of nitric acid or ammonium chloride as impurities. The water included in hydrous stannic dioxide has continuously differing degrees of bonding strength, which are classified into three parts: ( 1 ) absorbed water, bounded to the surface or the pore and being released at a temperature below 200°C; the quantity of the absorbed water varies with the method of preparation; ( 2 ) bonded water, bonded to the bulk by hydrogen b ond and being released gradually from 200 to 400°C; ( 3 ) structural water, being released at a temperature above 400°C.
Hydrous stannic dioxid e, forming a loosely-packed cassiterite structure just after precipita tion, crystallizes rapidly above 400°C, after releasing a large amount of water and adsorbed impurities, without forming any intermediates in the heating process.

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The DC and AC polarographic studies on Eu(III), Yb(III), and Er (III) ions in the molten salts of KNO₃-LiNO₃-NaNO₃ (53+30+17 mol %, mp 120°C) were carried out with DME and Ag/AgNO₃ reference electrode, at 180°C in an argon atmosphere. All the salts were used af ter drying them at 100°C in an argon atmosphere under a reduced pressure. And the values of Yslbo(plell )of E against log[i/ (i_d-i)] are 82.5, 96.0, and 97.5 mV for the reduction of Eu(III ), , and Er (III), respectively. The limiting currents of the metal ions are proportional to the square root of the mercury heights. On the basis of the linear dependence of limiting current on metal ion concentration, in the range of 0-4.0 mmol/kg for Eu(III), 0-1.0 mmol/kg for Yb(IIIM), and 0-1.0 mmol/kg for Er, it was confirmed that such limiting currents are diffusion controlled. The polarographic reductions of these metal ions are one-electron revers ible reactions and the half-wave potentioals Eu(III), Yb(III), and Er (III ) ions are -0.54, -1.10, and -1.21 V vs. Ag/AgNO₃, electrode, respectively. The AC polarogram of Eu(M) ion showed that the potential is -0.45 V vs. Hg counter electrode and the relation of peak current vs. metal ion concentration is linear in the range from 0 to 4.0 mmol/kg.

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About 350 blood samples were taken from the only adult s in healthy condition representing three regional populations Tokyo, Okinawa and New York. The statistical distribution of analytical values of various trace metals and regressi on line between zinc and magnesium in whole blood of human beings were investigated through the det ermination of 7 elements (Cd, C u, Fe, Mg, Pb and Zn) by means of atomic absorption s pectrometry with flame and flameless systems.
Statistical distribution data obtained by the quantitative atomi c absorption analysis showed an approximate “normal” or “log-normal” distribution both for “essential” and “nonessential”trace metals. Further, high correlation coefficients were obtained between magnesium and zinc. r = 0.393***, n = 142
This paper re vealed the levels of and relationships among the concentrations of trace metals i n human blood and the results may be used as one of a base line for the similar investigations.

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Eliminations of acetic acid from 1-(p-nitropheny1)-2-(2 and 4-quinolyl)ethyl acetates ([1 a]and [1b]) to give trans-2 and -4-(p-nitrostyryl)quinolines ([2 a] and [2 b]) have been studied kinetically in some alcohols at 60°C. The elimination was catalyzed by a base (KOH)and several acids (RCO₂H, HCl and BF₃ ). But no reaction was observed in the presence of sodium acetate alone or without any catalyst (Table 1). The catalytic ability of the acids decreased in the order: RCO₂H (R; Cl₃ C>Cl₂CH>CF₃>ClCH₂>Ph>CH₃) >HCl>BF₃ (Tables 1 and 3, and Fig.1). In the acid-catalyzed reaction, the rate of [1 a] was greater than that of [1 b], but [1 a] was less reactive than [ 1 b] in the hydroxide-catalyzed reaction (Tables 1and 4). The rate was expressed as v=k[RCO₂H]₃ [Substrate] for the carboxylic acid catalyzed elimination (Table 2). The rate ratio r= k([1 a])1k([1 b]) decreases from 5.7 to 1.2 with increasing acidity of carboxylic acids and dielectric constant of solvents (Fig.2). Salt effect on the acetic acid-catalyzed elimination was studied in ethanol-water (22: 1 v/v). No normal ionic strength and common anion effects were observed for both substrates. However, the rate increase of [1 b] was proportional to [AcOM]₀^1/2 (Fig.3). The kinetic isotope effect (k_h/k_D)was measured for the elimination of [1 a] in some protic solvents (Table 5). The value of k_H/k_D was larger than unity in all cases, suggesting a rate-determing elimination of β-hydrogen. The value of k_H/k_D increases with the increasing basicity of the attacking base on the β-hydrogen for the carboxylic acid-catalyzed elimination. This is consistent with a transition state from the nearly El to the symmetrical. Possible mechanisms are proposed and discussed.

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Air containing 2000 ppm vinyl chloride and a chlorinated compound such as chlorine (Cl₂), sulfur dichloride, thionyl chloride, trichloroethylene, tetrachloroethylene, nitrosyl chloride and nitryl chloride was irradiated by 100 watt high pressure mercury lamp at room temperature. Photo-decomposition of vinyl chloride was accelerated by the addition of these chlorinated compounds, and more than 99% of vinyl chloride disappeared by the irradiation within 60seconds. With the use of Cl₂ as accelerator, photo-decomposition of vinyl chloride in the air by UV irradiation with a high pressure mercury lamp was more accelerated than that with low or super low pressure mercury lamp. The reaction rate was also promoted by the addition of oxygen and ozone. Both hydrogen chloride and carbon dioxide were observed as main products and chloroacetaldehyde as a trace product. The initial degree of decomposition increased with the decrease in the initial concentration of vinyl chloride and with the decrease of Cl₂. The initial degree of decomposition was proportional to the reciprocal of the initial concentration of vinyl chloride and to the square root of Cl₂. The photo-oxidative decomposition of vinyl chloride in the air containing both, Cl₂ and ozone was faster than that containing Cl₂ or ozone alone. The initial degree of decomposition in the presence of chlorine dioxide was half as compared with that in the presence of Cl₂ with same concentration. On the basis of these results, a mechanism of photo-oxidative decomposition of vinyl chloride in the air containing Cl₂ was discussed.

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Air containing one of fluorocarbons (1000 ppm) such as chlorodifluoromethane (CHClF₂), chlorotrifluoromethane (CClF₃), dichlorodifluoromethane (CCl₂F₂), 1, 1-difluoroethane (C₂H₄F₂), bromochlorodifluoromethane (CBrClF₂), bromotrifluoromethane (CBrF₃), 2, 2-difluoro ethylene (C₂H₂F₂), chlorotrifluoroethylene (C₂ClF₃) and tetrafluoroethylene (C₂F₄) was irradiated by mercury lamp at room temperature. In the both cases of CCl₂F₂ and C₂ClF₃, the photo- decomposition in the presence of oxygen was faster than that in the absence of oxygen. Both carbon monoxide and carbon dioxide were observed in the irradiated gas. The initial degree of decomposition of fluorocarbons, chlorofluorocarbons, unsaturated fluorocarbons and unsaturated chlorofluorocarbons increased with the decrease in wavelength, and that of bromofluorocarEons with the increase in wavelength. The initial degree of decomposition of C₂ClF₃ with UV irradiation by a high pressure mercury lamp (100 W) was about 1000 times that of CCl₂F₂ and about 50 times that of CBrClF₂. The photo-oxidative decomposition of C₂ClF₃ also took place by sun light irradiation, 60% of C₂ClF₃ disappeared under outdoor exposure within 3 days. While in the case of CCl₂F₂, t he reaction did not occur under outdo-or exposure during one week. The reaction of C₂ClF₂w as accelerated by both chlorine and ozone, while those o f CCl₂F₂ and CBrClF₂ were not. On the other hand, CF₄ and C₂H₄F₂ scarcely affected th e decomposition of ozone, while CBrClF₂a nd C₂ClF₃ remarkably accelerated that. In the case of CCl₂F₂, t he initial degree of decomposition of ozone increased proportionally with the increase in the initial concentration of CCl₂F₂(log[CCl₂F₂]).

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Air containing NO and NO₂ was irradiated by a mercury lamp in the presence of various kinds of gaseous compounds such as NH₃, SO₂ and butadiene. NO in the air was rapidly converted into NO₂ by UV irradiation with a high pressure mercury lamp (100 W) at room temperature. By UV irradiadiation, both NO and NO₂ in the air were reduced by the addition of NH₃, SO₂, ethylene, butadiene, isoprene, vinyl chloride and methanol. And they were decomposed more rapidly by the addition of mixture of NH₃ and butadiene than with NH, or butadiene, alone. The photo-reaction between NO and NH₃ in the air brought about the decomposition of O.8 mol of NH₃ and the formation of 1.1 mol of N₂ with respect to the decomposition of unit mole of NO. The photo-reduction of NO in the presence of NH₃ scarcely proceeded in N₂, while that was remarkably accelerated by the addition of a small amount of 0₂. The reaction rate in the air increased with an increase in the concentration of NH₃. The reaction did not depend on reaction temperature in the range of 0 to 80°C. The photo-reduction rate of NO with NH₃ by different light sources was the order with super low>low> high pressure of mercury lamp. The conversion rate of NO to NO₂ by UV irradiation with low pressure mercury lamp was larger than that with high or super low pressure one. On the basis of these results, a mechanism of the photo-reduction of NO with NH₃ in the air was discussed.

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Stereoisomeric 2-t-butyl-1-methylcyclohexanols [1] were dehydrated under several rerction conditions and the products were examined to disclose the reaction mechanism.1-t-Butyl-6methylcyclohexene [ 5 ] as well as 2-t-buty1-1-methylenecyclohexane [2 ], 1-t-butyl-2-methyl cyclohexene [3] and 6-t-butyl-1-methylcyclohexene [ 4 ] were obtained in an AcOH-H₂SO₄ mixture (method A) or with P₂O₃ in hexane (method B). The composition of these olefins changed gradually to that of the equilibrium mixture during the course of the reaction (Table 1). By using POCl₃ in pyridine (method C) as a dehydrating agent, only [2], [3] and [ 4 ] were formed. The major products were [3 ] and [2 ] from cis and trans [1 ], respectively.

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γ-Ray induced addition reaction of 19 kinds of esters to hexafluoropropene was carried out as a part of studies on synthetic aspects of free-radical addition to fluoroolefins. Esters RCOOR' (R, R' -=CH₃, CH₂CH₃, CH₂CH₂CH₃, CH(CH₃)₂, CH₂CH₂CH₂CH₃, CH₂CH(CH₃)₂ ), [1a-j], gave in considerable yields the corresponding 1: 1 adducts which c onsisted of several isomeric esters carrying a fluoroalkyl-side chain at different positions. The ratios of isomers of the 1: 1 adducts indicated the following trends of apparent addition reactivities of the carbon atoms in an ester molecule: (1 ) -CH>>CH₂ >-CH₃, ( 2 ) the carbons in the alkoxyl group (R'O) were more reactive than those in the acyl group (RCO), and ( 3 ) the carbons with increased distance from the carbonyl group showed much increased reactivities. The last two trends, ( 2 ) and ( 3 ), were opposite to those reported in radical addition reactions of esters to alkenes. Whereas diethyl carbonate [1r] reacted similarly, esters containing an electronegative group RCOOCH₂CH₂ (R=CH₂F, CHClF, CH₂Cl, CHCl₂, CCl₃, CH₂CN, C₆H₅), [1k-q], either gave the 1: 1 adducts in much lower yields or gave no adducts at all, suggesting that the electro negative groups decrease reactivity for addition. γ-Butyrolactone [1 / s] gave no adduct.

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Catalytic hydrodesulfurization of dibenzothiophene over two kinds of cobalt-exchanged Y zeolites (CoNaY and CoNH₄Y) has been studied by using the batch method. The effects of acidic properties, which was estimated by means of amine titration, on the desulfurization activity of zeolite catalysts were examined.
The acid amount ( + 0.8 ≤ H₀≤ +6.8) of CoNaY zeolite, pretreated at 500°C, increased con siderably when ion was exchanged by cobalt from 27% to 61% (Fig.1) and the correlation corresponded to that of acid amount and desulfurization activity (Fig.8). The acid amount of CoDeY zeolite, prepared by the pretreatment of CoNH₄Y at 500°C, was in the range of 1.6 to 2.0 mmol/g (H₀≤ +3.3) and independent of the number of acid sites, regardless of io n exchange level (Fig.1, 9). The catalytic activities of CoDeY and CoNaY zeolites increased with the degree of ion exchange, reaching maximum for 40% and 70% ion exchanged zeolite, respectively (Fig.4). The acid amount of CoY (up to 40%) was in the following order; CoHY (CoNH₄Y pretreated at 350°C) >CoDeY >CoNaY (Fig.1, 3). But the order of desulfurization activity was CoDeY >CoHY>CoNaY (Fig.4). On poisoning the CoDeY and CoNaY zeolites with indole, the activities decreased seriously with the amount of indole until approximately 1 mmol of indole/g-cat and the activity of CoDeY became less than that of CoNaY (Fig.7).
The results indicate that the desulfurization activity of CoNaY catalyst depends on acid amount (+0.8≤ H₀≤ +6.8). However, there is no simple relationship between the acidic propenties of the surface and the desulfurization activity of CoDeY. The hydrodesulfurization of dibenzothiophene is remarkably promoted due to cobalts and acid sites produced by the calcination of ammonium ion sites of CoDeY zeolite.

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The decompositions of azobisisobutyronitrile were studied at 70°C under nitrogen and oxygen atmosphere in the presence or absence of transition metal salts to elucidate the interactions between metal ions and peroxyl radicals. The rate of gas evolution or absorption was measured by following the pressure change using pressure transducer. The decomposition with or without added radical inhibitor suggested that, in contrast with ordinary alkyl peroxyl radicals, significant fractions of 1-cyano-1-methylethylperoxyl radicals undergo the mutual interactions without evolution of oxygen.
In acetic ac id, the addition of manganese (II) acetate gives an anomalous pressure-time curve, which suggested that peroxyl radicals are captured efficiently by manganese(II) ions to yield hydroperoxide, and the manganese(II) ions are in turn oxidized to manganese(III) ions. As hydroperoxide accumulates, its decomposition by manganese ions becomes important. The analyses in terms of visible absorption and iodometric titration suggested the following reaction to occur:
Despite cobalt(II) and cobalt(III) salts react with peroxyl radicals rapidly, they are stabilized predominantly without electron transfer. At higher cobalt concentrations, the rate of gas evolution approaches to the value, calculated by assuming that all the biomolecular interactions of 1-cyano-1-methylethylperoxyl radicals evolve one molecule of oxygen like ordinary alkylperoxyl radicals. Manganese(III) ions contributes similarly.
In chlorobenzene, both manganese(II) and cobalt(II) ions are oxidized efficiently by peroxyl radicals to higher valence states. Acetylacetone chelate and particularly manganese salts are liable to be attacked by peroxyl radicals. Manganese phthalocyanine was also considered to stabilize the peroxyl radicals probably in terms of the electron transfer mechanism.

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The dediazoniation of substituted (m-or p-) benzenediazonium tetrafluoroborate (R-C₆H₄-N₂BF₄, R=H, Me, MeO, Cl, Br, NO₂, COOR' and OPh) in aqueous solutions (pH 1-7) was studied kinetically. The concentrations of diazonium salts were determined by measuring the concentration of the azo compound formed by NW acid colorimetrically. The main products of the dediazoniation were phenols and phenylazophenols. The decomposition rate is of first order with respect to the concentration of the diazonium salt and the rate constants ( k ) are markedly dependent on the pH values of the medium: at lower pH the values of k are constant, but above a certain value of pH it increases with pH linerly. These results were explained in terms of the equilibriums between diazonium ion and diazotate, ArN₂⁺ ↔ ArN₂OH ↔ArN₂O^- and it was concluded that the values of observed k at lower pH is the rate const ant of the dediazoniation of diazonium ion. The values of k depend also on the substituents. Hammett's relation between log k and σ is set up linerly for meta and several para (CN, NO₂and COOEt) substituents whereas for other para substituents some scatter from the linearity is found. The scatter was reduced by using σ₁+1.8|σ_R| instead of σ in plotting. This deviation was explained in terms of the resonance electron donability of the substituent and the stabiliza tion of the initial state.

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Polypropylene resin composites, comprised of fine particles of sulfonated graft-polymers of titanium(IV) oxide (average diameter of particles being O.4, μ) / styrene dispersed in a polypropylen e matrix, were shaped into sheets. By treating the sheets with hot water, the heterogeneous cation exchange membranes of excellent electrical and mechanical properties, were obtained. The effects of concentrations of poly ( styrenesulfonic acid), bonded to surfaces of titanium(IV)oxide particles, on the properties of heterogeneous cation exchange membrane were investigated in detail. This kind of heterogeneous cation exchange membrane has low specific resistance and high ionic transport number, despite the low concentration of poly (styrenesulfonie acid) in this membrane (salt splitting capacity being 0.64 meq. /g-dry membrane). This result was quite surprising when considering the fact that only the surfaces of cation exchange resins are effective for migration of cation through the heterogeneous cation exchange membrane. These facts may give another proofs against the effective roles of the cavities, which are formed between the cation exchange resin particles and the interface of polypropylene matrix as a result of hot water treatment, and of the surfaces of cation exchange resins in these heterogeneous cation exchange membranes.

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Polyurethanes containing benzimidazole units were prepared by the polycondensation reactions of bis(phenylurethane)s with diols. The reactions were initiated after dissolution of urethanes in initially molten diols. The reaction products solidify as the reactions proceed, and the polymerization reactions proceed in solid state at such two stages, the previously reported reaction of bis(phenylurethane) with diamines or with diamino dicarboxylic acids. It was elucidated by this study, that the latter stage of polymerizations proceeds at above the glass transition temperatures of the formed polyurethanes. The polyurethanes containing benzimida zole units have an excellent thermal stability.

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Kinetics of the transesterification of methyl benzoate (MB) with ethylene glycol (EG) catalyzed by the metal acetylacetonates was studied at 15O-17O°C. The rate constants determined from the relation R_D=k[MB] ([EG]>1 mol, [Complex] <3 x1O^-3 mol) are in the following order:
Zn( acac)₂ ( eg) > Zn (acac)₂ > Co( a cac)₂ ( e g) > Co( acac)₂ ( H ₂O)₂ >>Ni ( acac)₂ ( H ₂O)₂ > N i ( acac)₂ ( eg) ( H₂O>) Cu( acac)₂ On the basis of the data of electronic as well as infrared sp ectra, gas chromatography, acid values, and X-ray diffraction, the reaction mechanism for this reaction was discussed by considering ( 1 ) the change in coordination structure of the metal complexes, ( 2) the nucleo philicity of the mixed complex formed between the catalyst and EG, ( 3 ) the side reactions.

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Zinc methacrylate (ZMA), prepared from methacrylic acid and zinc hydroxide, was polymerized and copolymerized by using α, α'-azobisisobutyronitrile as an initiator in N, N-dimethylformamide. The polymer formed is insoluble in any of the organic solvents examined and contains unchanged carbon-carbon double bond (20-30%) as a pendant group. The content of the double bond was found to be independent of the monomer concentration and of the conversion. This could be explained as follows: the intermolecular addition occurs during the formation of poly- ZMA and the poly-ZMA, having double bond in its side chain, is formed. Next, the rapid exchange reaction between the polymer and ZMA monomer to form methacryloyloxy group continues. The ligand exchange reaction brings about crosslinking of the polymer.
Content of syndiotactic triad of the polymers obtained from ZMA wa s determined after conversion of them to poly (methyl methacrylate). The poly (methyl methacrylate) contains syndiotactic triad (about 40%) and this content is almost independent of polymerization temperature over the range from -78 to 150°C.
In order to estimate the radical polymeriza tion ability of ZMA, copolymerizat ions with styrene and methyl methacrylate were made. Q and e values of ZMA were calculated on the basis of the results of the copolymerization with styrene to be 1.45 and 0.68, respectively.

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The polymerization of 2, 4-, 2, 5-, 2, 6-, 3, 4- and 3, 5-dimethylstyrene (DMS) and their copolymerization with methyl methacrylate (MMA) were carried out by using azobisisobuty ronitrile (AIBN) as an initiator. The rates of polymerization (R_p) were expressed by the following equations: 2, 4- D M Sand 2, 5-DMS at 60°C: R_p=const. [AIBN]^0.4[Monomer]^1.4, and 3, 4-DMS and 3, 5-DMS at 60°C: R_p= const.[AIBN]^0.4[Monomer]^1.2.
The polymer of 2, 6-DMS was scarcely obtained by the use of AIBN at 60°C. In the copolymerization, the order of Q values of the o, o' -disubstituted group is one-tenth, which belongs to unconjugated type. The interplanar angles between ethylenic bond and benzene ring in the o-substituted groups were calculated on the basis of the ultraviolet absorption spectra. The result shows that the lowering of Q values of o, o'-disubstituted group is not attributed to the bulkiness of o-substituted methyl groups but to the inhibition of conjugation, resulting from planar twist between ethylenic bond and benzene ring, and that relative reactivity of 2, 4-, 2, 5 or 2, 6-DMS correlates to the interplanar angle between ethylenic bond and benzene ring.

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A sulfonic acid cation exchanger was prepared by bromoacetalizing the previously reported poly ( vinyl alcohol) beads, followed by crosslinking with sodium sulfide and sulfonatin g with sodium sulfite; a carboxylic acid cation exchanger was prepared by acetalizing the beads with glyoxylic acid; a phosphorylated cation exchanger was prepared by allowing the beads to react with phosphoryl chloride in chloroform. Further, amphoteric ion exchangers were prepared by allowing the bromoacetalized beads to react with phosphoryl chloride in chloroform, followed by amination with various amines. The cation exchange capacities of sulfonic, carboxylic and phosphorylated types are 2.4, 3.8 and 4.9 milliequivalents per gram of resin, respectively. The cation and anion exchange capacities of amphoteric ion exchangers are 2.4 and 2.6 milliequivalents per gram of resin, respectively. The degrees of swelling of sulfonic, carboxylic, phosphorylated and amphoteric ion exchangers are approximately 11, 15, 4 and 6 milliliters per gram of resin, respectively. The bead-shaped exchangers are extremely resistant to alkali and acid.

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Bisphenol-, α, ω-diol and glycol type epoxide resins were cured with p, p'-diaminodiphenylmethane, a, w-diamines and triethylenetetramine.
Relaxation behavior was fo llowed by observing dynamic mechanical properties and segmental structures of these resines, and α-, α'-, β- or γ-relaxation was observed in the neighborhood of 170, 80, -50 or -130°C, respectively.
The β-relaxation is attribu ted to the motion of hydroxyl-ether group and the γ-relaxation is attributed to the motion of methylene linkage or polyethylene glycol linkage in these resines.

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As N-(β-hydroxyhexadecyl)diethylenetriamine forms chelate complexes with metallic ions in an aqueous solution showing excellent foaming ability, this character may be utilized to remove metallic ions by foaming. The adsorptive character of an aqueous solution of β-0HC₁₆DT- Cu(II) complex in a batchwise type column has been studied to know the effective conditions for removing metallic ions by foaming.
From a result of the rate of r emoving copper ion in the range of 1.57 x 10^-8-3.15 X 10^-7mol/cms, keeping the concentrations of the agent (collector) and copper ion to be equimolar, it has been presumed the mechanism of the adsorption to be of Langmuir type. If the kinetics was dealt with by assuming the average diameter of bubbles to be constant, the solution to be complete by miscible and the foam to leave from the column as a piston flow under the condition of equilibrium, the plots of the reciprocal of initial rate against the initial concentra tion of residual solution gave a straight line. From the slope and the intercept, the parameters of Langmuir adsorption, i. e., 6 Γ*/d and K, have been derived to be 1.84 X 10^-8 molfcms and 2.13 X 10^-8 mol/cm³, respectively.
From the concentr ation curves of residual solutions derived from the above values, it has been found that experimental values agreed well with the theoretical ones when the value of C/C₀ was more than 0.4.

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The adsorption characteristics of polyethylene glycols (PEG) with various molecular weights on two kinds of commercial activated carbons were investigated.
The experimental data for adsorption equilibria of P EG were expressed by Langmuir-type adsorption isotherm within the range of equilibrium concentration from sev e r al to several hundreds of mg/i. The adsorption capacity q_∞(g/g-C) tended to increase with incr e asing molecular weights of PEG. However, _∞* ( mmol/g-C) had the maximum value at m olecular weights of 150 or 300. The adsorption of PEG with higher molecular weights was c o nsidered to be affected by the pore size of the activated carbons.
The effective intraparticle diffusion coefficients D₁'(cm²/sec) were calculated from the estimated values of adsorption rates in an agitated tank, and those values showed a tendency to decrease with increasing molecular weights. The breakthrough times by down flow column ad s o rption exhibited complicating features with molecular weights, because of the competing e ffects of adsorption equilibria and adsorption rates on molecular weights.

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Adaptabilities of the liquid metal (alloy) catalysts to the dehydrogenations of C₁₀-terpene alcohols and aromatic alcohols have been experimentally investigated using a conventional flow reaction technique. The catalysts were In, Tl, Ga, Zn, Zn-In, and Zn-Sn; the experimental conditions were as follows; temperature: 330-580°C, pressure: 1 atm.
Experimental results (Table 1) have shown that the dilution of the ractant alcohol with acetone is effective not only to elevate the convertibility but also to raise the selectivity. Almost all alcohols except for nerol, isopulegol, and myrtenol have been found to be catalytically dehydrogenated to give corresponding aldehydes or ketones with enough high convertibility and high selectivity (Table 2). Excellent activity and selectivity of the liquid thallium catalyst have been found in the reaction of terpene alcohol.

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The reduction of K₂Cr₂O₇ with (NH₂)₂CSO₂ in 1 N H₂SO₄ solution was studied. From qualitative analysis of reaction solution and mass balance, reaction equation was determined as follows: 2Cr₂O₇^2-+3 (NH₂)₂CSO₂ + 10 H⁺ 4 Cr³⁺+ 3(NH₂)₂C0 + 3 SO₄^2- + 5 H₂O The rate of reduction can be expressed by the following 2 nd order rate equation dx/dt = k (n₀-x ) (m₀-3 x/2)where n₀ (mol/l) is the initial concentration of K₂Cr₂₇, m₀ (mol/l) is the initial concentration of (NH₂)₂CS0₂ and x (mol/l) is the concentration of K₂Cr₂O₇ reacted at time t.

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The hydration of r-cadinene [ 1 ] and 8-cadinene [ 2] with mono-, di and trichloroacetic acids was investigated and five products were isolated by means of distillation and gas chromatography.
The structures of 1(10)-cadinen-4 α-ol [ 3 ], 4-cadinen-10 α-ol (T-cadinol) [ 4 ], 1(10)-cadinen 4 β-ol. [ 5 ], 4-cadinen-10 β-ol (α-cadinol) [ 6] and 10(15)-cadinen-4-ol [ 7 ] were assigned on the basis of their physical constants, IR and NMR spectra.
Hydration of [1] yield [6 ] as a major product, while [2 ] yielded mainly [3].

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