With regard to acetone adsorption on (100) planes of five alkali halide crystals, i. e. LiCl, NaCl, NaBr, KCl and KBr, the adsorbed amounts, the isosteric heats of adsorption, and the adsorption entropies have been determined. The isosteric heat measurements showed that acetone is adsorbed on the surface of these salts by an interaction between the surface cation and an oxygen atom in the carbonyl group with C=O axis oriented perpendicularly to the salt surface. The order of magnitude of the isosteric heats compared at the given equivalent amounts of the adsorbed in low coverage was as follows: NaBr>KBr>NaCl>KCl>LiCI. Since the interaction energies between acetone molecule and the surface cations of NaBr, KBr and NaCl were considerably large, an adsorptive activity of the surface cations being exposed on the surface, i. e. (111) plane, should be taken into account in studies on adsorption of polar substances on alkali halides.
Acetone molecules were recognized to be adsorbed on NaCI and NaBr in the ratio of one acetone to two cations on the (100) planes of the salts, and they were also adsorbed on KCl and KBr, whose lattice spacings are longer than that of NaBr, in a ratio above 1: 2. On the other hand, they were adsorbed on LiCl, whose spacing is shorter than that of NaCl, in a ratio belo; v 1: 2. These phenomena are reasonably interpreted in terms of cross-sectional area of an acetone molecule.

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In order to study the purity of carbazole, the evaporated thin films of carbazole-anthracne and carbazole-phenanthrene mixed crystals containing 10^-8∼10^-8 mol/mol of anthracene and of phenanthrene, respectively, were prepared on quartz plates. Commercial carbazole was purified by treatment with maleic anhydride and chloranil, with metallic sodium in 1-pentanol, followed by chromatography on an alumina column. It was finally zone-refined. The fluorescence spectra, the fluorescence lifetimes and the time-resolved. fluorescence spectra were measured both at room and liquid nitrogen temperatures.
Anthracene of the concentration less than 10^-7 mol/mol in the carbazole can be detected by the fluorescence spectra, and anthracene, less than 10^-9 mol/mol, can be detected by the timeresolved fluorescence spectra. However, it was difficult to measure the, concentration of anthracene in the carbazole by the fluorescence lifetimes, because their fluorescence were in the same range. The - phenanthrene less than 10^-5mol/mol in the carbazole can be detected by the fluorescence spectra, that of less than 10^-6 mol/mol bry the time-resolved fluorescence spectra, and that of less than 10^-7 mol/mol by the fluorescence life times. It was concluded that the concentration of anthracene and plienanthrene: containeci in 'corn mercial carbazole as impurities could be decreased to less than 10^-9mol/mol and 10^-7mol/mol, respectively, by the method described above.

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It was found that 1, 8-diazabicyclo[5.4.O]undec-7-ene (DBU) is an excellent catalyst for the synthesis of methyl formate from methanol and carbon monoxide under mild conditions. The kinetic study of the carbonylation under pressure in methyl cellosolve solution showed that the rate of methyl formate formation is of the first order with respect to carbon monoxide pressure and to the concentration of methanol and DBU, and that the methyl formate decom- poses to carbon to carbon monoxide, and methanol with DBU under the reaction, leading to the equibrium.
Based on these results, the following mechanism was proposed:
On this basis the following rate equation was derived in good agreement with the observed result.
H₀₀: Solubility constant of CO (mol/. atm), fco: Fugacity of CO (atm), mo, do: Initial charges of CH₃OH and DBU (mol), ffeq: Concentrations of HCOOCH8 produced and at equilibrium(mol. /-)., The rate constants k', overall equilibrium constants K', heat of reaction Ha and the apparent activation energy Ea were determined to be k' = 1.83 X 10^-3(80°C), 4.27X10^-3(100°C), 7.53 X 10^-3(120°C), K' = 0.662(80°C), 0.842 (100°C), 1.012 mol.1-1 (120°C), Ha=27 kcal and Ea= 12 kcalimo1^-1

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Ring-closure reaction of ethyl 4-hydroxyimino-2-oxovalerate [ 1 ], catalyzed by sulfuric acid, brings about isoxazole, and ethyl 3-rnethy1-5-isoxazolecarboxylate (2) is formed in the absence of hydroxylamine. However, in the presence of hydroxylamine, ethyl 5-methyl-3-isoxazolecarboxylate [3 ] and ethyl 3-methyl-5-isoxazolecarboxylate [ 2 ] are formed. The relation between the reaction rate and the sulfuric acid concentration is illustrated in Fig.3. On the basis of the kinetic consideration and the results of analyses of the intermediates formed during the ring-closure reaction, possible pathways for ring-closure of ethyl 4-hydroxyimino-2-oxovalerate in the presence of hydroxylamine were suggested.

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Ethylene hydrogenation catalyzed by molybdenum nitride has been studied at -78°C. The rate of reaction was O.6 th and zero order with regard to hydrogen and ethylene, respectively. An average value of the isotope effect kllIkp=1.8 was observed. The reaction of H₂D₂ mixtures with ethylene and the reaction of H₂ with C_2CH₄-C_2CD₄ mixtures were also carried out at -78°C. Isotopic mixing of hydrogenes in ethylene was quite rapid and reached an equilibrium in 10 minutes both in the presence and absence of hydrogen. While the H₂-D₂ exchange was retarded by ethylene. Hydrogen added to ethylene was not considered to undergo isotopic exchange before the reaction with ethylene, because the isotopic composition of product ethane (d, , d and d2 species) was close to that of the reactant hydrogen (H₂, HD, and D_O). From these results possible mechanisms for the hydrogenation of ethylene are proposed.

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The adsorption of NH₃, H₂0, 1-butene, and 1, 3-butadiene on cation-exchanged sulfonate resins was studied at 60∼130°C. The water coordinated with the cation and the counter anion of the resin was removed by pre-evacuation above 130°C(Fig.1) and the adsorption of 1, 3- butadiene on Fe (III)-exchanged resin was remarkably enhanced by this pretreatment (Fig.2). The amount of adsorption generally increased with the basisity of the adsorbate: 1-butene <1, 3-butadiene<H₂0<NHs, and strongly depended on the electronegativity of the exchanged cation (Fig.6). The fact that the amount of adsorption per unit amount of cation increased with the increase in the cation concentration on the resin indicates that the activity to the cation site is not uniform (Fig.5). As for a series of 3 d-transition metal cation-exchanged resin, the activity for the adsorption of NH₃, 1, 3-butadiene, and H₂0 was in the order, Mn²⁺ <Co²⁺, Ni²⁺, Ni²⁺ >Zn²⁺ (Fig.7). Similar trends were also found for the heat of NH₃ adsorption and for the heat of wetting of water (Fig.8).

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Distribution of nickel ions in the cation sites of NiHY zeolites was studied on the basis of the selective chemisorption of CO and NO which had different adsorption properties. The chemisorptions of CO and NO were examined on a series of the NiHY zeolites having dif- ferent degrees of exchange, and it was concluded that while CO chemisorbed on the nickel ions in site II, NO chemisorbed on those in sites II and Ir. Thus, the amount of the nickel ions occupying sites II and II' can be determined separately by the selective chemisorption of these gases. The most suitable condition in the chemisorption measurement of CO was 25°C and pressures less than 100 Torr, while in the case of NO it was 0°C and the same pressure range. It was also shown that the distribution of nickel ions was markedly dependent on the degree of exchange as well as on the temperature of pretreatment.

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The polarization characteristics of a sintered CdS electrode in aqueous Na2SO4 solution (basic solution) under illumination were studied. The anodic photocurrent began to flow at ca. -1.45 V vs. SCE in a solution containing S^2- ion, but it began to flow at ca. -0.7 V in a solution without S^2- ion. The oxidation of S^2- ion in a solution by a hole to change it into an elemental sulfur at the anode occurred in preference to the photodecomposition of a CdS electrode itself. In a solution containing sufficiently concentrated S^2- ion, the deposited sulfur at the anode by the photoelectrochemical reaction dissolved in S^2- ion to form polysulfide ion (Sx2-). Due to the above reaction, the photocurrent during the photoelectrolysis of the cell showed a steady value. On the basis of these results, an electrochemical photocell using undissolved CdS anode could be realized.

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New crystals, Na₂Li₂Ti₆O₁₄, Li₂Na_4-2Ti₂O₇, and Li₂Na_4-2Ti₆O₁₄ were synthesized by the hydrothermal reaction of titanium dioxide with sodium hydroxide and lithium hydroxide. The process of formation and the region of synthesis were discussed; and their crystal structures were determined.
Na₂Li₂Ti₆O₁₄ is isomorphous with K₂Li₂Ti₆O₁₄ and orthorhombic, with following cell dimensions: a= 16.38 Å, b=5.76 Å, c= 11.30 Å and Z=4. LixNa₂_Ti30, is also isomorphous with Na₂Ti307 and monoclinic, with following cell dimensions: a=8.55 Å, b=3.78 Å, c=9.11 Å, 8= 101.5° and Z= 2.
Li₂Na_4-2Ti₆O₁₄ is orthorhombic, with space group P21nzn and with following unit cell dimensions: a=37.28 Å, b=9.32 Å, c=2.90 Å, Z=4. The structure of this crystal is outlined below: six octahedra of TiO, are joined by edges, lengthening zigzag in the direction of b-axis and form layers. A unit cell is composed of four layers which are at right angles to a-axis; and among these layers alkali-metal atoms are located.

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The thermodynamic quantities concerning the complex formation of polyphosphate ions (n= 6 and 8, n: the average degree of polymerization of polyphosphate) with Mg(II), Ca (II), and Sr( II ) were determined and compared with those obtained previously for pyro-, tri-, and tetra-phosphate complexes with these metal ions: (1) The thermodynamic stability constants of the complexes of the types ML, MHL, and NM. (where M, H, and Lare metal ion, hydrogen ion, and polyphosphate ion, respectively) were evaluated from pH titration data obtained at various ionic strengths at 25°C. (2) The enthalpy changes associated with the formation of the 1: 1 complexes (ML) at 25°C were determined by a direct calorimetric methed. On the basis of these values and the thermodynamic stability constants of the 1: 1 complexes, the corresponding entropy changes were calculated. As shown in Table 1, the complex formation is endothermic and the entropy change is always positive and large. The 4S° and 4H° increase with increasing average degree of polymerization of the polyphosphates (n); the rate of increase is relatively large below 4, and then becomes smaller (Fig.2). The 4S° and iiH° also increase with decresing radius of the metal cations (Fig.2). All these results are interpreted in terms of the present theories of metal chelate formation in aqueous solution.

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2-Thioxo-5-nitroso-1, 3-dimethylperhydropyrimidine-4, 6-dione (TNDP) was synthesized and fundamental conditions for the determination of iron with the TNDP was investigated. TNDP reacts easily with iron (III) to form a water-soluble blue complex. Iron (II )-TNDP complex has an absorption maximum at 630 nm against a reagent blank and shows a definite absorbance over the pH range from 5.5 to 6.8. The calibration curve obeys the Beer's law over the range from 0 to 3 pglml of iron (II) at 630 nm; the molar extinction coefficient of the complex and the sensitivity for log(10/1) = 0.001 level are 2.23x 10 cm'mol'. l and 2.49x 10-9 μgcm^-2, respectively. The variation coefficient was 0.68% in the case of 1 pg/m/ of iron (II ). The ratio of iron (II ) to TNDP in this complex was confirmed to be 1: 3 by the continuous variation method. Large amount of cobalt (II) and copper 00 interfered with the determination.

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Addition and redox reaction of p-benzoquinone or potassium p-benzoquinonesulfonate with Na₂SO₃ were discussed by comparison of the oxidation-reduction potential of these quinones (Eq) with that of Na₂SO₃ (Eq). It was confirmed that the redox reaction proceeded when the difference (Eq)E, was large and the addition reaction proceeded when this difference was small.
The intermediate formed during the redox reaction was detected with polarographic method on the boundary condition of the addition and the redox reaction. From the structural assignment of this intermediate, the mechanism of the redox reaction is described.

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Hydration of various isoprene dimers (2, 6-dimethyl-2, 6-octadiene [2], 2, 6-dimethy1-1, 6- octadiene [3], 2, 7-dimethyl-2, 6-octadiene [4] and 2, 3, 6-trimethyl-1, 5-heptadiene [5]) with an equimolar amount of chloroacetic acids (mono-, di-, and trichloroacetic acid) has been studied.
Hydration of [2] yielded 2, 6-dimethyl-6-octen-2-ol [6] as the main product and 2, 6- dimethy1-2-octen-6-ol [7] as the minor one. Isomer [3] yielded mainly [6] and gave 2, 6- dimethy1-1-octen-6-ol [8] as the minor product. Only 2, 7-dimethyl-6-octen-2-ol [9] was obtained from [ 4 ]. Hydration of [5] yielded both 2, 3, 6-trimethyl-5-hepten-2-ol [10] and 2, 3, 6-trimethyl-1-hepten-6-ol [11].
These reactions proceeded almost quantitatively under optimum conditions.

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An adsorbent was prepared from Australian brown coal (8-16 mesh) by treating 100 g of the coal with 10 g of NaOH in 60 ml water at room temperature for 90 minutes. It was necessary to impregnate the NaOH treated coal with 10 mg/g of CA²⁺ for preventing the elution of humic acid.
Since the NaOH treated coal from Australian brown coal was easily degradated into the fine particles during the manufacturing processes, it was pelleted by using commercial vinyl acetate emulsion as a binder agent. In the drying process, the moisture of the sample was adjusted closely to 45% and the particle size was sieved in the range of 8-16 mesh. The compressive strength of each particle was 800-1200 g.
The measurement of adsorbability of the pelleted samle for dyes and metal ions was carried out in aqueous solutions. The values of ion exchange capacity expressed in meq/g were 1.38, 1.25, 1.24, 1.21, 1.15, and 0, 96 for Pb²⁺, Zn²⁺, Cu²⁺, Ni²⁺, Cd²⁺ and Methylene Blue, respectively. On the other hand, adsorption was hardly observed with a dye anion, CI. acid blue 62. Discussion is given on these results.

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It was found that ethylbenzene was oxidatively dehydrogenated at about 200 to 300°C on supported palladium catalysts modified by halogen ions to give styrene in high selectivity. Since bromine ion was found to be most effective in modifying the activity and selectivity of the catalyst, sodium bromide was use in this experiment. The apparent activation energy was 7.8 kcal/mol and 16.1 kcal/mol for styrene formation and carbon dioxide formation, respectively. While the rate of styrene formation was proportional to the partial pressure of ethylbenzene, it was expressed by a Langmuir equation with respect to oxygen.
Other alkylbenzenes such as propyl- and butylbenzenes were also oxidatively dehydrogenated on the catalyst to form alkenylbenzenes in which double bond existed at the β-position to aromatic rings. The reactivity of each alkylbenzene decreased with the increase in the carbon number of the alkyl group. The alkylbenzene with straight chain exhibited high activation energy in the reaction and suppressed the formation of styrene when it was reacted competitively with ethylbenzene. This fact was explained on the basis of a possible assumption that the alkylbenzene with straight chain adsorbed on the catalyst in larger quantities than ethylbenzene.

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The structure of acacetin-7-trioside [1], a component of the leaves of Robinia pseudoacacia, was elucidated. Upon hydrolysis of [1] with hydrochloric acid, acacetin, D-glucose, L-rhamnose, and D-xylose were obtained, while upon partial hydrolysis of [1] with 10% acetic acid, linarin (acacetin-7-8-rutinoside) and D-xylose were formed as main products. Upon methylation of [1] with dimethyl sulfate, nonamethylate [2] was obtained; upon hydrolysis of this with acid, 5, 4'-dimethylapigenin, 2, 3, 4-tri-O-methyl-L-rhmnose, 2, 3, 4-tri-O-methyl-D-xylose, and 3, 4-di-O-methyl-D-glucose were formed. In terms of NMR spectrum, Cl linkage of D-xyloside was confirmed to be β-bond.
On the basis of the above results the structure of [1] is 7-0- [O-α-L-rhamnopyranosyl0-[8- D-xylopyranosyl- (1-2) ]-8-D-glucopyranosyl] acacetin.

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Solvent sorption properties for sulfonated ion-exchange resins in nonaqueous solvents, by comparing them with those for unsulfonated resins, were investigated. Seventeen polar and nonpolar organic solvents were used and the resins used were of gel and macroreticular (MR) types.
The solvent sorption of ion-exchange resins (Dowex 50 WX 8 of gel type and Amberlyst 15 of MR type) is stronger for MR type resin, retaining a rigid and porous structure, than for gel type resin. The swelling of these resins increases with increasing solubility parameter of the solvents (δ1 ) in δ1≥10 for H-form or δ1≥12 for Na-form, and does not increase in the solvents, whose 8, is less than the above value. These were considered to be due to the interac- tion between solvents and sulfonate groups in the resin. The correlation between swelling properties of resins and solvent properties, such as dielectric constant, dipole moment, and donor number, was not good.
The swelling properties of unsulfonated resins differ from those of the sulfonated ion-exchange resins. The swelling of gel-type polystyrenes with 1 and 8% divinylbenzene contents is the strongest in the solvent with δ1=9. On the other hand, MR-type Amberlite XAD resin (styrene-divinylbenzene copolymer) adsorbs any solvents tested equally in the pore of the resin, and hence, the swelling was scarecely observed.

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The extruded films of high density polyethylene were stretched at a room temperature and. the effects of crystallization induced by drafting under extrusion on the stress-draw ratio were investigated. The necking was produced at an early stage of stretching. With increasing draft ratio from 1 to 200, the necking stress an increased from O.85 x 10⁸ to 3.3 x 10⁸ dyne/cm' and the neck draw ratio αn decreased from 7.5 to 2.4. The equation of necking stress derived from thermodynamics, an=xt1Gml(αn -1), well explained the relation observed about the extruded film, where x is the crystallinity and ziGm is the free energy of fusion.
The stress a at a uniform deformation, induced by further stretching after neck draw, increased with a draw ratio a. The measured values of a and a were tested whether they obeyed the equation of a unform deformation, =x4Gmlar, (1-α/αm), and the maximum draw ratio am at completely extended state was estimated by this equation. The estimated value was proved to decrease from 24 to 6.8 with an increase in draft ratio.
Assuming that the microfractures of lamellae into small crystal blocks were induced at a process of deformation by the concentration of stress on tie molecule and tie link which were produced by drafting, the maximum draw ratio was considered to be related to the size of crystal block or the number of folded chains in it. The size of crystal block estimated by this assumption decreased from 100 to 30A with increasing draft ratio, and therefore, the concentra tion of tie at the surfaces of lamellae was found to increase from 0.04 to O.15 with increasing draft ratio.

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The photodegradation of celluloic materials or of certain model compounds, due to exposure to ultraviolet light, has been followed mainly by a change in infrared spectra or in the degree of polymerization of the samples. The degree of polymerization of common cellulose fiber containig amorphous regions or of amorphous cellulose, decrystallized specially, was reduced by the scission of glucosidic bonds in the molecule in terms of an irradiation with a light of 253.7 nm; and carbonyl groups were detected in the irradiated samples. However, highly crystalline cellulose (acid-hydrolysis residue) did not show an appreciable change in the degree of poly- merization and its infrared spectra did not change in terms of an irradiation with a light above 200 nm.
The scission of molecular chain in the amorphous cellulose proceeds randomly and obeys the first-order kinetics.
The presence of water in the samples retarded the degradation of cellulose in terms of an irradiation with a light in the region of 253.7 nm. Thiseffect was attributed to water molecules, adsorbed to cellulose by hydrogen bonding, which may decrease an optical sensitivity in disordered regions.

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2, 4-Bis (p-nitroanilino) -6-substituted 1, 3, 5-triazines were prepared by the nitration of corresponding dianilino-1, 3, 5-triazines.2- (m-Nitroanilino) -4- (p-nitroanilino) -6-substituted L 3, 5- triazines were prepared by the nitration of 2-anilino-4- (m-nitroanilino) -6-substituted 1, 3, 5- triazines.2, 4-Bis (aminoanilino) -6-substituted 1, 3, 5-triazines, whose 6-position having no or a substituent such as methyl or phenyl group, were obtained by the reduction of the above dinitro compounds. Poly (amide-guanamine) [A] or poly (pyromellitamic acid-guanamine) [B] was prepared by the reaction of the above diamines with terephthaloyl and isophthaloyl dichlorides or with pyromellitic dianhydride, respectively. Poly (pyromellitimide-guanamine) [C] J was prepared by heating [B] in vacuo. Thermal properties of [A], [B], and [C] were determined by means of the TGA method. Decomposition temperature of [A] was 355∼454°C, that of [B] or [C] obtained from symmetric diamines was 480∼510°C, and that of [B] or [C] obtained from unsymmetric diamines was 450∼480°C.

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Polyamides containing a-diketone linkage in their main chains were prepared in terms of the method of low-temperature solution polycondensation of 4, 4'-bis (chloroformyl) benzil with aro- matic diamines in N-methylpyrrolidone (NMP)-LiCl solution. The resulting polyamides were allowed to react with o-phenylenediamine to give polyamides containing quinoxaline ring in their side chains. Thermal properties of these polyamides were characterized by means of DTA, DSC, and TGA. It was found that polyamides of m-phenylenediamine and 4, 4'-diaminodiphenyl ether containing quinoxaline ring were thermally more stable than the corresponding parent polyamides containing α-diketone linkage.

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Mechanism of an initiation reaction of graft copolymerization onto 6-nylon was investigated by using a monomer mixture (1: 9) of methacrylic acid (MAA) and methyl acrylate or methyl methacrylate. With regard to BPO, as the conversion rate of the monomers was very low, AIBN or a mixture of a, a-dimethylbenzyl hydroperoxide and L-ascorbic acid was employed as an initiator. Graft efficiency slightly decreased with increasing amount of an initiator but increased with increasing concentrations of CaCl₂ and MAA. The graft efficiency was very high at the initial stage of the reaction if the concentration of MAA was high, but decreased with increasing reaction time and reached a constant value of 23%. On the basis of these results, the mechanism of the initiation of the graft copolymerization is the extraction of a hydrogen contained in 6-nylon in terms of a radical formed from MAA and not a direct initiation in terms of the radical in an initiator.

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For the purpose of an effective utilization of plastic wastes, thermal gasification of polyethylene was carried out under atomospheric pressure by using a flow procedure of fixed bed reactor, in which the overheated steam introduced as a heat carrier. By deriving an experimental equation, Ip= Tθ, the product yield was estimated, where IF is intensity function (°Cseca), θ is a reaction temperature (°C), θ is a residence time (sec), and a is constant (-).
Pyrolysis conditions were: temperature, 590∼800°C; residence time, O.6∼6.5 sec; dilution ratio of polymer toward steam, 2.5 (by weight).
Gasification easily proceeded even in a relatively low temperature range, and olefins containing mainly ethylene were obtained in high yield.
When the residence time was 3.2∼3.4 sec And dilution ratio was 2.5∼2.7, the maximum ethylene yield of about 32 wt% at 700°C, the total yield of ethylene, propylene, and 1-butene of about 58 wt% and the total gas yield of about 75 wt% were observed at 650°C.
As a dilution ratio was not so important, operating factors were restricted to reaction temperature and residence time. For a given yield of the product, they were interchangeable. The equation for methane wasoTθ0.04.
As IF correlated with product yields, the product yield could be successfully predicted by an appropriate choice of pyrolysis conditions.

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The purpose of this research is to elucidate the mechanism of the extraction of uranium by trioctylamine in benzene. The extraction equilibria of uranyl ( VI) nitrate were investigated in an aqueous solution of nitric acid, whose concentration being less than 6 mol/l. The extraction rates of uranyl(VI) nitrate in 3 mol/l nitric acid solution were measured by using a stirring cell with a flat liquid-liquid interface, and analyzed in terms of a simple model.
The distribution equilibrium could be expressed by the following equation upon considering the extraction reaction, in which one mole of UO₂ (NO₃)2 associates with two moles of amine nitrate (R3NHNO₃):
where n=2, Ka = 2.20, 81= 5.0, 1/2= O.001, K= 5.50 x 10^-4.
It was found that the extraction rates could approximately be expressed by the model, in which UO₂NO₃⁺ alone, as an uranyl complex in an aqueous phase, and an electric field were considered.

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The object of this investigation is by the ion flotation method to remove Hg( II) from a dilute aqueous solution containing various metal salts, using N-alkylethylenediamines (R-en). The formation constants betreen metal ions and R-en were determined at 25°C. These values were similar, regardless of alkyl chain length, but the values of Hg(II) complexes were smaller than that of ethylenediamine-Hg(II) complex. The order for the formation of these R-enmetal complexes was as follows: Fe (III) > Cu(II) > Hg(II) > Pb( II ) > Zn (II) > Cd(II) > Ca (II) (Table 2).
The optimum pH region in the ion flotation was above 4.0 for Hg(II) and above 6.5 for Fe(M). Cu(II), Pb(II), Zn(II) Cd(II) and Ca(II) scarcely showed a flotation effect (Fig.2-4). From an aqueous solution containing Hg(II), Fe(III), Cu(II), Pb(II), Zn(II), Cd(II), and Ca(II), He(II) could be selectively floated at pH 4.5 by usig R14-en or Ri-en, and at pH 5.7 by R-en or 1: Z12-en, leaving other cations in a solution (Fig.6).
R16-en, containing the largest alkyl chain, was the most effective agent for the elimination of Hg(II) and the minimum amount of Hg(II) in a residual aqueous solution was 1.2 ppm at pH 4.6. The minimum amount of Hg(II) was lowered to 0.031 ppm at pH 8.0 by the addition of Pe(II) and by using R-en (Fig.7).

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An anomalous increase in coercive force and stability of the acicular iron oxide powder (Fe²⁺ /Fe³⁺: 1.1) treated with (NaP0₃)n was investigated at a room temperature∼300°C under the pressure of 0.4 mmHg in an air. The maximum coercive force was observed upon heating at 150°C. This increased coerive force decreased linearly with treating time. The coercive force of the sample treated at 150°C for 40 minutes was approximately constant. An anomalous increase in coercive force was observed when some water was present during the process of treatment. The experiments suggested that water may play an important role to form a chemical bond between iron and phosphorous ions.

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Various diols, containing 3, 3, 4, 4-tetrafluoro-1, 2-cyclobutylene and 3, 3, 4, 4, 5, 5-hexafluoro1, 2-cyclopentylene group, HOIVIVCCH(CF2)HCCR3R4OH (n: 2 or 3;: H or CHs), have been synthesized by the addition reaction of alconols, e. g., methyl, ethyl, and isopropyl alcohol, with (polyfluorocyclobutenyl) or (polyfluorocyclopentenyl)alkanols under the irradiation of r-ray.
The apparent reactivity of alcohols observed in this addition reaction is in the following order:
C₂H₅0H> CH₃OH>(CH₂) ₂CHOH
The reverse was found for the effect of substituents in polyfluorocycloalkenes on the reactivity; and the reactivity of cycloalkenes having -C(CHs)20H group is the most and that of -those having -CH₂OH group is the least.
The (tetrafluorocyclobutenyl)alkanols are generally more reactive than the (hexafluorocyclopentenyl) alkanols.

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Dehalogenation with excess tin powder in polyphosphoric acid was used for the synthesis of triphenodioxazine (5, 12-dioxa-7, 14-diazapentacene) [5 a] and its analogues. For example, 6, 13-dichlorotriphenodioxazine [4 a] was converted to [5 a] in 55.8% yield. Similarly, 3, 10- dibromo- [4 b], 3, 10-dichloro- [4 c], and 1, 2: 8, 9-dibenzo- [4 d] derivatives of [4 a] were reduced to the corresponding halogen free compounds.
A facile route to triphenodithiazine (5, 12-dithia-7, 14-diazapentacene) [9] was also established with these reagents. Replacement of halogenes by hydrogens in these heterocycles brought about a decrease in melting point and strong hypsochromic shifts in electronic spectrum.

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