The effect of urea on the interaction of synthetic polypeptides(poly(β-benzyloxycarbonyl-Lornithine) (PLO(Z)), poly (t-benzyloxycarbonyl-L-lysine) (PLL (Z)) and poly (γ-benzyl-L-glutamate) (PBLG)) with cholesterol was investigated by the monolayer technique and the polarized infrared spectroscopy for the collapsed films.
In the case of mixed PLO (Z)- and PLL (Z)-cholesterol monolayers, the two film components are immiscible in the absence of urea in the subsolution and are miscible in the presence of urea. The miscibility increases with increasing urea concentration. On the other hand, in the case of mixed PBLG-cholesterol monolayers, the two film components are miscible even in the absence of urea, and in the presence of urea the miscibility changes remarkably with the concentration of urea(Fig.3). The change of miscibility is ascribed to the breakdown of the hydrophobic hydrated structure of the film in the interfacial region by the action of urea.
Polarized infrared spectra of the collapsed monolayers showed that polymer components in the monolayer were aligned in the direction parallel to the barrier (Figs.5 and 6).

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The hydrogenation of 1, 3-butadiene over LaCo₅H_n was conducted in the temperature range -65°C to -40°C, and a plausible mechanism of the hydrogenation was proposed. The alloy LaCo₅H_2.4 was prepared from LaCo₅ according to an ordinary procedure with repeated heating and cooling in hydrogen atmosphere. The hydrogenation of 1, 3-butadiene was conducted in a conventional gas circulation system in a pressure range of 1, 3-butadiene 0.85∼5.1 cmHg in the absence of hydrogen in gas phase. The hydrogenation rate was measured with gas chromatography. The rate was unaffected by the pressure of 1, 3-butadiene and increased in proportion to the concentration of the hydrogen atoms absorbed in LaCo₅H_2.4. The rate was approximately the same as the desorption rate of the absorbed hydrogen atoms from LaCo₅H_2.4 under a reduced pressure. Therefore, it was concluded that the migration process of the absorbed hydrogen atoms from the bulk of the alloy to its surface was rate-determining. The composition of the products [1-butene: 65%, cis-2-butene: 3%, trans-2-butene: 18%, (cisltrans=0.17) and butane: 14%] remained unchanged during the reaction. From the NMR and MS spectrometric analyses of the products of the hydrogenation of 1, 3-butadiene over LaCo₅H_2.4, it was also concluded that 1-butene and 2-butene were formed by 1, 2- and 1, 4- addition, respectively.
Under similar conditions the hydrogenation of 1, 3-butadiene mixed with hydrogen was conducted over LaCo₅H_2.4 evacuated at -65°C, 0°C and 350°C for 1 hr under a reduced pressure. This hydrogenation rate, which was much lower than the rate of 1, 3-butadiene over LaCo₅H_2.4 was zeroth- and first-order with respect to the pressure of 1, 3-butadiene and of hydrogen respectively. The reaction of 1-butene was also examined over the degassed catalysts in the absence or presence of hydrogen in the gas phase. The rate of isomerization of 2-butene (cisltrans=15∼20) was independent upon the pressure of hydrogen, while the rate of formation of butane was zeroth- and first-order with respect to the pressure of 1- butene and of hydrogen respectively. From these results, it was concluded that the adsorption process of hydrogen in gas phase was rate-determining in the cases of these hydrogenation reactions.

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To elucidate the chemical reactivity of the hydrogen atom absorbed in LaNi₅, the hydrogenation of unsaturated compound such as acrylonitrile, 1-hexene, or 2-methyl-1, 3-butadiene in liquid phase was carried out over LaNi₅H_6.0. The hydrogenated alloy LaNi₅H_6.0 was pre- pared from LaNi₅ according to an ordinary procedure by repeated heating and cooling in hydrogen atmosphere. The reactions were carried out approximately at a room temperature in the absence (A) or the presence (B) of gaseous hydrogen, and in some instances in the solvent such as cyclopentane, oxolane, or etc. The rate of hydrogenation was followed by gas chromatography.
The hydrogenation of substrates except benzene and methyl acetate markedly proceeded, and the reaction rate in the presence of additional molecular hydrogen was almost the same as that in the absence of molecular hydrogen. When molecular hydrogen was added to LaNi₅, no change in hydrogenation reaction occurred. In the case of (A), a certain amount of hydrogen in the alloy was desorbed in gas phase during the reaction, and it remarkably influenced the substrate. In this case, the total decreasing rate of hydrogen in the alloy, whose hydrogen is the sum of that consumed by the hydrogenation and that desorbed as a molecular hydrogen, was relatively lower than the desorption rate in the absence of the substrate under vacuum.
The desorption rate of hydrogen from LaNi₅H_6.0 in hexane, cyclopentane, or oxolane, which was used as a solvent in the hydrogenation, was remarkably lower than that under vacuum. Considering the above results, it was concluded that the rate-determining step of the hydrogenation is the migration process of the absorbed hydrogen atoms from the bulk of the alloy to its surface which was almost completely covered with the strongly adsorbed substrate.

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A method of obtaining reliable kinetic data for the reaction of methanol over a copper catalyst (180°C, 1 atm) is described.
On account of a significant decay in the catalytic activity, it was difficult to derive a rate equation from experimental data without corrections. Thus the decays of the catalytic activity were measured under standard conditions, and the resulting decay rates were used to correct and normalize the experimental data.
The normalized data could be expressed by the experimental equation v₀=. Since this being a good approximation of the theoretically predicted equation
where k=1.83mol/g-cat.hr and K_MeOH = 9.94atm^-1, it was concluded that the treatment presnted in this paper is reasonable.

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Effective Nd segregation coefficient in the Nd: YAG (Nd-doped Y₃Al₅O₁₂) crystal growth by pulling method was determined precisely over 0∼1.3 atom% Nd concentration range at a 0.6 mm hr^-1 growth rate, Two Nd: YAG crystals (∼20 g) were grown from a large melt (∼1kg). Neodymium concentrations in the crystals and residual melts were estimated by 4orescent X-ray analysis, and a value of 0.21 was obtained as the effective segregation epefficient. Next, the optical absorption coefficient of Nd: YAG crystal at 5889 A absorption peak was measured in order to analyze a small specimen for Nd by optical absorption nleasurements. The optical absorption coefficient of 0.97 mm^-1 atom%^-1 was determined in tills way.
The Nd concentrations, calculated by the segregation coefficient, agreed well with those obtained by optical absorption measurements at 5889 Å for six successively grown Nd: YAG oystals. Therefore, the obtained segregation coefficient, 0.21, was confirmed as a reliable value for the Nd: YAG crystal growth by the pulling method.

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Hydrous Ti(IV) oxides were prepared, at room temperature, by adding aqueous ammonia to concentrated or diluted Ti (SO₄)₂ solutions until pH of the solutions were raised to 3.0, 4.5, 6.0 and 8.0, respectively. Chemical, thermal, IR absorption spectrum and X-ray diffraction analyses were made of these hydrous oxides. Their specific surface areas and adsorption capacities of (UO₂(CO₂)₂)^4- ions in alkaline solutions were also measured. The results obtained can be summarized as follows:
1) The crystallinity of the hydrous Ti (IV) oxide decreased linearly with increasing pH of the mother solution the crystallinity of the hydrous oxide prepared at pH 8.0 was about one fifth of that of the hydrous oxide prepared at pH 3.0 (Fig.6).
2) The specific surface area of the hydrous oxide increased linearly and markedly with increasing pH of the mother solution (Fig.7). The adsorption capacity of the oxides showed a remarkable increase with increasing pH of the mother solution (Fig.8). The oxides with maximum adsorption capacity were prepared from the solution of pH6.0 for the concentrated Ti(IV) solution, and from the solution of pH4.5 for the diluted Ti(IV) solution.
3)The chemical composition of the hydrous oxide was greatly dependent on the concentration of Ti(SO₄)₂ in the mother so1ution (Table 1 and Table 2). The result revealed that the chemical composition had close relation ship to the hydrolytic mechanism in Ti(SO₄)₂ solution.
4)The dependencies of the crystallinity and the adsorption capacity etc. on pH of the mother solution were explained in terms of the hydrolytic mechanism, the growth and aggregation model of hydrous Ti(IV) oxide polymers, and the constitutional formulas of the hydrous oxides after heated at 50°C (Fig.12, 13 and Table 3).

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A chromium sheet was phosphidized in phosphorus vapor of 10 to 760 Torr at 800∼1000°C in a closed vessel. The apparatus and experimental methods were the same as in previous papers.
The layer structure of the reaction zone proved to be (P₄ and P₂ vapor) /CrP/Cr₂P/ (Cr) from X-ray analysis and electron microprobe analysis for phosphide layers formed. The phosphidation followed a parabolic behavior and therefore the rate was regarded as limited by a diffusion process. A marker experiment indicated that chromium was the component that diffused. The parabolic rate constant, K_p, in 1 atm phosphorus was given as a function of the absolute temperature, T, by the following expression:
K_p=0.14 exp(-35 x 10³/RT), g².cm^-4.min^-1, (800∼1000°C)
The pressure dependence of K^p was not clearly recognized.
It could be concluded from the diffusion profiles and the above result that the rate-determining lattice-diffusion of cation took place in the course from the inner layer (Cr²P) to the outer layer(CrP). The diffusion coefficient varied with the concentration of diffusion species.

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The oxygen-pressurized leaching of metallic nickel powder was studied kinetically in ammoniacal ammonium carbonate solution. The dissolution of nickel required the presence of ammonium ions as well as oxygen; the degree of dissolution was determined by the amount of ammonium ions. When the sample amount was less than 6 g-Ni/200 ml, the rate-determining step was assumed to be diffusion of dissolved oxygen through a liquid boundary film. In this case, the initial velocity of dissolution of nickel powder was expressed by the following equation, an apparent activation energy being L 5 kcal/mol (30∼410°C):
1-(1-x)^1/3=k't,
where x was the degree of nickel dissolution, k' was constant, and t was reaction time. The dissolution of nickel powder was significantly accelerated by increasing the partial pressure of oxygen and the stirring velocity. These phenomena also supported that the rate-determining step was diffusion of oxygen. When the sample amount was more than 6 g-Ni/200 ml, the rate-determining step was assumed to be dissolution of oxygen into the solution.
The nickel in coal ashes obtained by steam-gasification was easily leached as long as the nickel was present in a state of metal. Thus, more than 90% of the nickel could be leached within 10 min from a coal ash sample, in which the gasification degree was about 70%, under the conditions: (NH₄)₂CO₃0.5 mol/l, free NH₃ 3 mol/l, reaction temperature 50°C, partial pressure of oxygen 4 atm and stirring velocity 1000 rpm. When the gasification degree. was nearly 100%, 80% of the nickel was converted to oxide and the degree of leaching of nickel was as low as about 20% under the same conditions.

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When a fluorine bearing mineral is heated, a part of hydrogen in the mineral is released as hydrogen fluoride. To determine H₂O(+) content of such samples, hydrogen fluoride released must be converted to water. In this work the tube filling materials which can quantitatively convert hydrogen fluoride into water are investigated. The sample is weighed into a platinum crucible. The crucible is placed in the combustion tube. After passing a purified nitrogen gas to sweep water adsorbed in the apparatus, the gas is introduced into a Karl Fischer titration vessel which contains an anhydrous mixture of methanol and ethylene glycol, and the mixture is titrated by the Karl Fischer reagent(factor 0.9 mg H₂O/m/). After a blank test, the sample is heated in a high frequency induction furnace at a constant flow rate of carrier gas. Hydrogen compounds, such as hydrogen and hydrogen fluoride, are released from the sample and converted to water by reacting with reagents in the conversion tube. The water is determined in the same manner as in the blank test.
Potassium hydrogendifluoride which yields hydrogen fluoride quantitatively by its thermal decomposition is used as a standard sample. The conversion ability of three kinds of the tube filling materials is examined. The quantitative conversion of hydrogen fluoride into water is attained at about 400°C, by filling palladium asbestos, copper (II) oxide and their mixture, as shown in Fig.2. The recovery of hydrogen in potassium hydrogendifluoride as water is 100.1 %, 95% confidence limits being 100.1 ± 0.49%.
Water content of muscovite which contains 0.47% fluoride is determined by the proposed method, yielding ay.4.26%. The 95% confidence limits are 4.26 ± 0.03_x%. For the same sample mixed with a known amount of potassium hydrogendifluoride, the results are in excel- lent agreement with the former results.

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A method for selective and sensitive determination of antimony in atmospheric dusts was developed. This method consisted of three consecutive stages i. e., the extraction of antimony (III) into benzene, the conversion of antimony to stibine with zinc powder, and the sweeping of evolved gases into quartz cell of atomic absorption spectrophotometer.
A given amount of sample dust was digested with 9 mol/l sulfuric acid containing a small amount of hydrogen peroxide on a hot plate. After filtering the insoluble residue off, the filtrate was evaporated to nearly dryness. The residue was taken up with 20 ml of 9 mol/l sulfuric acid-O.1 mol/l ascorbic acid-0.01 mol/l potassium iodide and extracted twice with 10 ml portions of benzene. Antimony in the combined organic phase was stripped with 10 ml of 0.005 mol/l EDTA solution. The EDTA solution was evaporated to nearly dryness together with 5 ml of 9 mol/l sulfuric acid and a small amount of hydrogen peroxide. The residue was dissolved in 25 cm of 6 N hydrochloric acid. The solution containing less than 0.7 μg of antimony was put into a reaction vessel, followed by the addition of a pellet of zinc, and the solution was covered tightly with a plunger. After one min, generated stibine was swept into the cell with nitrogen as the carrier gas. Antimony ranging from 0.1 to 3 μg was determined with an error of 5%. Without the extraction with benzene, Fe, Ni, Co, Cu, Cr, and Se much interfered with the determination. The proposed method can be applied to the determination of antimony in natural, marine, and industrial waste waters as well as rocks.

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The polarographic behaviors of copper (II), lead (II), cadmium (II) and manganese(II) in oxydiacetate solutions were studied adjusting the ionic strength to 0.4 with sodium perchlorate. The reversible two-electron reduction waves were obtained in the pH ranges from 3.0 to 8.6 and from 9.4 to 11.5 for the copper system, from 1.2 to 7.3 and from 12.2 to 12, 6 for the lead system, from 1.4 to 10.1 for the cadmium system and from 5.3 to 8.6 for the manganese system. Metal complexes, MX, MX₂^2-, MX₃^4-, M (OH)X^-, M (OH)X₂^3-, M(OH)₂X^2-, M (OH)₂X^4-, M(OH)₃X^3- for copper, the same type of species and M(OH)₄X^4- for lead and MX, MX₂^2- and MX₃^4- for cadmium and manganese were assumed and their stability constants were calculated by Schaap and DeFord-Humens' method. The logarithms of the overall stability constants at 25°C were 3.1, 4.7, 5.7, 10.0, 11.9, 12.7, 14.6, 15.8 for copper complexes, 5.0, 5.9, 7.3, 10.9, 12.9, 16.3, 18.6, 19.2, 21.0 for lead complexes, 2.6, 3.9, 5.2 for cadmium complexes, 2.7, 3.8, 5.3 for manganese complexes.
The square-wave polarograms for copper(II), bismuth (III), lead (II) and cadmium (II) at pH 8.0 were obtained separately from each other in the oxydiacetate solutions of 4.0 × 10^-2 mol/l. The lower limits for determination of the metals were O.06, 2.0, 0.2, 0.3, 0.5 and 0.3 ppm, respectively.

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Polarographic behavior of purine alkaloids at the dropping mercury electrode was studied in neutral and basic DMF solutions. Caffeine was reduced at E_1/2=-3.14 V(vs. Ag/0.1 mol/l Ag⁺) in neutral and basic DMF solutions. Since theobromine and theophylline have an imino hydrogen atom, and dissociate into the nonreducible anions in basic DMF solutions, these alka, loids gave well-defined anodic waves corresponding to the reaction with a mercury electrode, at E_1/2=-0.74 V for a theophylline anion, and E_1/2=-0.92V and -1.00V for a theobromine anion.
R^- + Hg(electrode) R-Hg⁺ + e
The height of the anodic waves of these anions and a cathodic wave of caffeine, were not affected by the presence of less than 3% of water in DMF solutions, and were proportional to the concentration of each purine alkaloid.
Simultaneous polarographic determination of the purine alkaloids from 1 × 10^-4 to 2 × 10^-3 mol/l was possible in the basic DMF solutions containing 0.01 mol/l tetraethylammonium hydroxide and 0.25 mol/l urea. The proposed method is simple and rapid, since no prior treatment or separation procedure is required.

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Additivity of ¹³C-NMR chemical shifts of the ring carbons and amide carbonyl carbons of benzamide derivatives was examined. The additivity rule is quite precise in the cases of ring carbons, and those chemical shifts are estimated within the errors of ± 0.5 ppm. In the case of carbonyl carbons the influences of the second and third substituents on the chemical shift is less than that of the first substitution of the same substituent groups. The correlation between Hammett's σ values of each substituents and the para-carbon chemical shifts of the benzamide derivatives is not so precise compared with the strictness of the additivity rule. Alkyl group substitutions give the shifts to somewhat lower fields than the other groups, and substitution by halogens give the shifts somewhat to higher fields. Thus the correlation diagram shows a band of ± 2ppm in width.
The correlation between the carbonyl shifts and the Hammett's a values also shows deviations in a range of ± 2ppm in width.

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The dehydration reactions of BaCl₂.2H₂O and SrCl₂. thermogravimetry (TG and DTG) and differential thermal analysis (DTA) under pressures of 1, 4, 10 and 40 atm.
For BaCl₂.2H₂O, the DTA curves showed two peaks at 1 atm and three or four peaks at pressures above 4 atm, and the TG curves showed two steps over the range of 1∼10 atm and 3 steps at 40 atm. For SrCl₂.6H₂O, the DTA curves showed five peaks at respective pressure, and the TG curves showed three steps at 1 atm and two steps at pressures above 4 atm. As a common effect of pressure to the dehydration of these two salts, DTG peaks and some of DTA peaks shifted to higher temperatures with a increase in pressure, but a few peaks remained unshifted on DTA curves in spite of increasing pressure. The peaks which corresponded to these unshifted peaks on DTA curves were not observed on DTG curves. The unshifted peaks on DTA curves were attributed to the endothermic reaction accompanied by the dissociation of coordination water. The DTA and TG curves suggested that both salts formed the intermediate state between anhydrous and monohydrate states.

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Methyl-substituted p-benzoquinones are known to undergo the two type reactions with Na₂SO₃ -the redox reactions (Eq. (1) and (2)) and the reaction via 1, 4-addition (Eq. (3)).
MPQ + HSO₂^- + H₂O=MH₂Q + SO₄^2- + H⁺ (1)
MPQ + 2HSO₃^-=MH₂Q + S₂O₆^2- (2)
MPQ + HSO₂^-=MH₂QS^- (3)
where MPQ, MH₂Q and MH₂QS^- represent methyl-substituted p-benzoquinones, methylhydroquinones and methylhydroquinonesulfonates, respectively.
The progress of those two type reactions have been investigated from the standpoint of the difference ΔE(=E_MPQ-E_SS) between the redox potential of methyl-substituted p-benzoquinones (E_MPQ) and that of Na₂SO₃ (E_SS), and it was described in the preceding paper that those two type reactions mainly proceeded in the case of ΔE>0. In this paper, it was confirmed by the identification of the reaction products at by means of the polarographic method and the spectrophotometric measurement that the reaction different from Eq. (1), (2) and (3) proceeded mainly in the case of ΔE<0. The product in the trimethyl-p-benzoquinone-Na₂SO₃ system is, for example, 3, 4, 6-trimethyl-2, 5-dioxo-3-cyclohexene-1-sulfonate. In the methylsubstituted p-benzoquinone-Na₂SO₃ and the p-benzoquinone-Na₂SO₃ systems, a small amount of other products which were easily oxidized by the electrolytic oxidation were detected by polarographic method.

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Reactions of nitrosobenzenes with nitrogen monoxide were carried out under various conditions. Nitrosobenzene was easily diazotized by nitrogen monoxide in an aqueous ethanolic pyridine solution or in a weakly acidic aqueous ethanolic solution, but more than 3 molar equivalents of nitrogen monoxide were required to prepare the diazonium salt in a good yield (Table 2). Reaction of nitrosobenzene with nitrogen monoxide in an ammoniacal ether or dioxane gave an ammonium salt of N-nitrosophenylhydroxylamine (Table 3). The yield of the ammonium salt was increased by adding hydroquinone to the reaction mixture.

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The Claisen rearrangement of allyl phenyl ethers that have a number of ortho or para substituents varying from electron withdrawing to electron releasing groups was found to be catalyzed by zinc chloride. In the case of p-substituted compounds, the order of the magnitude of the catalytic effect of zinc chloride on the conversion was observed as follows.
CH₃O>CH₃>H>t-Bu>Cl>CHO≅/≈COCH₃>NO₂
Namely, the catalytic effect decreased with increasing the electronegativity of the substituent. In the case of o-substituted compounds, the catalytic effect of zinc chloride was remarkably different from that of para isomers, and the order was as follows.
CH₃O>COOCH₃>COCH₃>CH₃, CHO>H>Cl>NO₂>t-Bu
Particularly, the catalytic effect to the compounds having ortho carbonyl group was larger than that of para isomers. From the data of IR and others, it was considered that the cata- lytic action of zinc chloride on the Claisen rearrangement was occurred by coordination of zinc chloride to the ether oxygen at the transition state.
Consequently, it was supposed that the magnitude of the catalytic effect of zinc chloride to the conversion was governed by the intensity of coordination of zinc chloride at the ether oxygen, and that the intensity of coordination was controlled by inductive effect, steric hindrance and chelating effect of ortho substituent.

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The photochemical reaction of 4, 6, 6-trimethyl-5, 6-dihydro-2-pyridone [1] with ethyl vinyl ether [2] gave four [2+2]cycloadducts in which the ring junctions were cis-fused. The main product was exo-7-ethoxy-4, 4, 6-trimethyl-cis-3-azabicyclo[4.2.0]octan-2-one. The reaction was sensitized by sensitizers with triplet energy higher than 70 kcal/mol and promoted by aprotic, polar solvents. The reaction of [1] with methyl acrylate [7] gave three cis-fused [2+2]cycloadducts and 3-[2-(methoxycarbonyl) ethyl]-6, 6-dimethyl-4-methylene-3, 4, 5, 6-tetrahydro-2-pyridone. The main product was methyl 4, 4, 6-trimethyl-2-oxo-cis-3-azabicyclo[4.2.0]-octane-exo-8-carboxylate. This reaction was also sensitized, whereas fluorescence of [1] was quenched by [7] and not by [2].
From a kinetic study based on the quantum yields for the reaction of [1] with [2], several rate-constants were estimated.

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The dynamic mechanical property of poly(amic acid) and polyimide films with various draw ratios has been measured in air over a range from room temperature to 500°C at a frequency of 110 Hz, to elucidate the effect of molecular orientation on the dynamic viscoelasticity of these polymers. The variations in the dynamic strage modulus, E', and the dynamic loss modulus, E', of poly(amic acid) films with imidation were very complex, because the elimi-nation of absorbed solvent, the breakdown of hydrogen bonds, and the plasticizer-action of water, formed upon imidation, occurred simultaniously. The α-dispersion peak for polyimide was observed at 350∼390°C in the E'- or tan δ-temperature curve, and the E' value decrea- sed distinctly in the corresponding temperature range. Since this dispersion peak shifted toward lower temperature side with increasing draw ratio, the relaxation process seemed to be attributed to the slipage of the main chains along the drawing direction, being promoted by the arrangement of parts of ring-structure in the main chains parallel to the film plane.
The increase in the E' value, which is known to be due to the thermal deterioration, caused by crosslinking reaction, was observed in the temperature range from 355° to 400E°C. The temperature, at which E' value began to increase, shifted toward lower temperature side as the draw ratio became higher. This fact suggested that the orientation of molecular chains promoted the crosslinking reaction. Furthermore, from a comparison of the results obtained by the measurements in air with those in nitrogen, it was found that the air oxida-tion retarded the thermal deterioration being responsible for crosslinking reaction.

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The formation of the complexes of poly (methacrylohydrazide) (PMH) with bivalent transition metal ions, Mn(II), Co(II), Ni(II), Zn(II), Cu(II), and Hg(II), was investigated in terms of pH titration method in an aqueous solution with ionic strength of 0.1 at 25°C.
When the acid dissociation constants of PMH were measured in an aqueous solution with ionic strength of 0.10(KNO₃) at 25°C, pK_a1 and pK_a2 became 3.20 and 10.61, respectively. The formation constants for PMH-metal(II) complexes and the average number of ligand combined with each metal ion were measured by using the modified Bjerrum's method. The formation curves of PMH-metal(II) complexes showed that Cu(II), Hg(II), Co(II), Zn(II), Mn(II), and Ni(II) ions formed coordination 'compounds with six, four, four, three, two and one hydrazide group, respectively, in a high pH region. The order of each formation constants is shown below: Ni(II)<Mn(II)<Zn(II)<Co(II)<Cu(II)<Hg(II). It was recognized that the mercury(II) ion could form the stable complexes with PMH in a lower pH region than the case of other metal(II) ions.

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A simple method, to remove nitrogen monoxide of ppm levels from an air by passing this air through a bet of alkaline earth peroxides, was investigated. Removal efficiency depended on the relative humidity of sample gas and a small amount of nitrogen monoxide was removed without water. Each peroxide showed the maximum removal efficiency at the definite relative humidity; the relative humidity showing the maximum removal efficiency was the highest for BaO₂ and the order of it for each maximum removal efficiency was BaO₂>SrO₂>CaO₂>MgO₂. It was presumed that atomic oxygen produced by the reaction of peroxide with water oxidized nitrogen monoxide to dioxide at the first step, and the nitrogen dioxide was absorbed by the hydroxide of alkaline earth metal, produced upon reaction of peroxide with water. Presence of the maximum removal efficiency at the definite relative humidity was explained in terms of the balance of generation and consumption of atomic oxygen due to water; the more the excess water was the produced atomic oxygen, but the produced atomic oxygen recombined with excess water yielding hydrogen peroxide and therefore, oxidation of nitrogen monoxide decreased above the definite relative humidity.

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Microwave discharge in N₂ is known to produce N radicals, which react with NO in the following way:
N + NO → N₂ + O
The discharge was employed in order to study the decomposition of NO gas.
Experimental works were carried out in the two methods:
(I) Gas mixtures(sample gas) containing NO were passed through microwave discharge.
(II) Nitrogen gas was passed through microwave discharge and then mixed with the sample gas.
The measurements were made in a flow system at various pressures, flow rates and microwave output. The effect of additives and temperature on the decomposition of NO was also studied.
Microwave discharge was shown to decompose effectively NO gas in the both methods, I and II. Increase of the microwave output accelerates the decomposition of NO, whereas higher pressures and flow rates retard it. In these experimental conditions temperature shows no effect on the decomposition. Microwave discharge takes place only below certain pressures, which depend on the microwave output and flow rate.
The experimental observations were tentatively interpreted in terms of the production, reaction and quenching of N radicals.

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The selective adsorption ability of zinc ion on the macroreticular chelating resin (RMH) which had hydrazide groups and a few carboxyl groups, was investigated in batch and column operations.
In the batch operation, it was found that RMH did not adsorb calcium ion in a solution of ([Zn²⁺]/([Zn²⁺]+[Ca²⁺]))>0.6 and exhibited a favorable selective adsorption ability for zinc ion. However, when solutions of ([Zn²⁺]/([Zn²⁺]+[Ca²⁺]))>0.6 were passed through the RMH column, a considerable amount of calcium ion was adsorbed on RMH together with zinc ion. On the other hand, when waste solutions containing sodium ion, zinc ion and calcium ion produced in viscose rayon industry were passed through the RMH column, the amount of calcium ion adsorbed was smaller than that in the case of the above solution. This suggested that the adsorption of calcium ion on RMH was affected by sodium ion in the waste solutions. Calcium ion adsorbed on RMH decreased with increasing amount of sodium sulfate in the solution and with the decrease of the rate of flow during the adsorption operation. The break-through capacity of RMH was 22.2 grams of zinc per liter resin under the following conditions: loading solution of Zn²⁺ 445 mg/l and Ca²⁺, Mg²⁺ 37 mg/l (as Ca²⁺), total salt concentration 18.2g/l, pH 6.7, and space velocity 15/hr. This capacity was higher than that (Zn 13.2 g/l-R) in the case of a polyethylenepolyamine type resin reported previously. The elution of zinc ion adsorbed was made by passing 2∼3 N sulfuric acid solutions through the column. The solution of zinc sulfate recovered contained a few percent of calcium sulfate as an impurity.

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Several title compounds have been prepared by treatment of the corresponding benzyl alcohols with nitrosyl chloride in pyridine, and their decompositions in acetic acid and carbon tetrachloride have been investigated under various conditions. With lightly substituted benzyl nitrites, decompositions in both media led to the predominant formation of the benzaldehyde, while the benzyl acetate and benzyl nitrate were the respective, major products from the decompositions of hindered benzyl nitrites such as 2, 4, 6-trimethyl- and 2, 3, 4, 5, 6-pentamethylbenzyl nitrites. Hindered polymethylbenzyl nitrites and nitrites were found to behave differently towards the action of lithium aluminium hydride; the formers gave the expected benzyl alcohols while the latters were mostly reduced to the parent hydrocarbons.

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In air or in vacuo, photo- and thermal polymerization of methyl methacrylate (MMA) in the presence of α-tocopherol or its acetate were investigated. It was found that α-tocopherol inhibited the photopolymerization of MMA sensitized by benzoin ethyl ether and the thermal polymerization induced by benzoyl peroxide. On the other hand, it was confirmed that α-tocopherol acetate was able to initiate photopolymerization of MMA in the presence of oxygen. α-Tocopherol acetate acted as plasticizer and lowered glass transition temperature of the polymers. A fraction of α-tocopherol actate was presumed to be contained in the polymer chains from their spectral data.

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