The effects of hydrogen ion concentration on the absorption and fluorescence spectra of six halogen derivatives of fluorescein (DC'F, TCF, TB'F, TI'F, DCTB'F, TCTB'F) were studied in water-dioxan mixed solvent. These halogen derivatives may have four ionic forms in solution, i. e., monovalent cation, neutral form, monovalent anion and divalent anion. Absorption and fluorescence bands in various solutions were assigned to these ionic forms, and dissociation equilibrium constants, K, were calculated. The stronger the electron attractive force of halogen, the smaller is the pK value. For absorption spectra, the bathochromic effect of halogen atoms was observed and the effect in divalent anions was larger than that in monovalent cations. A red shift of fluorescence spectra (bathochromic shift) was also observed. Decrease of fluorescence intensity by heavy atoms in monovalent cations was larger than that in divalent anions.

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Crude chrysene (C181-112), extracted from coal-tar pitch, contains a small amount of anthracene and/or naphthacene as impurities. The most effective purification method was as tollows. The crude hydrocarbon (10 g.) was heated in boiling maleic anhydride (150 g.) with chloranil (8 g.) as an oxidizing agent about 2 hr. Hot toluene was added onto the reacted mixture, and the solution was boiled further for 1 hr. After removing the precipitates from the parent solution by filtration, the solid chrysene was obtained from the solution by about 50°C. And it chrysene was recrystallization from benzene. Further purification by zone refining was applied repeatedly. The fluorescence spectra and its life-time of solid chrysene were very effective to detect the impurities contained in the hydrocarbon. The fluorescence peaks of the high-purity chrysene at room temperature and also at liquid nitrogen temperature exist at 390, 412, and 435 nm, but the peaks of 400 and 425 nm result from homologous impurities. The life-time for the high-purity chrysene, 30.2 n. sec. at room temperature, decreased to 20 n. sec. when the sample was contaminated by a small amount of impurities.

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The distribution of the various doped cations (Li⁺, Al³⁺, Ga³⁺, and In³⁺) in the Co³o⁴ spinel was studied by the quantitative X-ray analysis and the electrical conductivity measurement. Li⁺ and Ga³⁺ ions exclusively occupied the A sites in the doped spinel, about 80 atom% of Al³⁺ ion the B sites, and Ins+ ions were distributed over both A and B sites. The solubility of In³⁺ and Li⁺ ions in the spinel was about 5 atom% respectively. The electrical conductivity measurement revealed that Li⁺ ions markedly increased the conductivity, and Ins+ and Ga³⁺ ions significantly and Al³⁺ ions slightly reduced the conductivity. These results support Wagner's model on the mechanism of the electrical conduction in the spinel.

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The state of dispersion and the electrochemical properties of iron oxide-sodium pyrophosphate solution system were studied. A commercial iron oxide powder prepared by calcination of FeSO₄.7H₂0, (BET surface area, 7.55 m²/g; hematite structure) was used in this study. The pH of zero point of surface charge (ZPC) obtained from pH titration (Fig.2) was 7.9. At this pH, iron oxide was most poorly dispersed in medium (water). In Na4P2O7 solution, the degree of dispersion generally increased with the increase of the concentration of solute, and complete dispersion was observed at the concentration of 4 x 10^-4mol/l. In acidic medium containing Na₄P₄o₇, however, the suspension was found to flocculate. For instance, the flocculated concentration at pH=4.0 was (0.38-1.88) x 10^-4 mol/l. The adsorption of Na₄P₂o₇ on α-Fe₂O₃ (at 25°C) followed Langmuir's isotherm. The mono-layer capacity varied with the pH of media, from 14.15 x 10^-7 mol/m2 at pH=4.0 to 5.34 x 10^-7 mol/m2 at pH=9.5. These results suggest that sodium pyrophosphate ions are adsorbed only on positively charged sites of a-Fe₂O₃ surfaces. The mechanism of dispersion is proposed as shown by a schematic illustration in Fig. 12. It was concluded that the degree of dispersion depended on the net charge of surface which was determined by both the pH of media and the adsorption of sodium pyrophosphate ions on a-Fe₂O₃ surfaces.

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The adsorption of lignosulfonate (LSA) on montmorillonite (Mtm) with different exchangeable cations (Nat, Ca²⁺ and Al³⁺) was studied over a wide range of pH. The LSA used was a fraction with an average molecular weight of 36000. The adsorption on Na-, Ca- and Al-Mtm was carried out in the aqueous solutions of NaCI (0.4 N), CaCl₂ (0.04 and 0.2 N) and A1C13 (0.03 N), respectively, so that the size of the spherical LSA molecule estimated from the intrinsic viscosity could remain almost constant as shown in Fig.2 throughout the experiments. Moreover, it is probable that the adsorption of LSA occurs compactly on the surface of Mtm, because the electrostatic repulsion among the molecules of LSA is reduced in such salt solutions. The surface area available for adsorption of the LSA, therefore, could be calculated as a function of the amount adsorbed alone. All the adsorption isotherms determined were of Langmuir type. As shown' in Fig.8, at the pH range from 1.6 to 7.1, the maximum amounts adsorbed and the surface areas available for the maximum amounts adsorbed per gram of Na- and Ca-Mtm remained within the range of 40-60 mg and 50-70 m², respectively. On the other hand, those of Al-Mtm at the pH range from 1.8 to 3.3 amounted to about 3 times (about 150 mg and 190 m2, respectively) as large as those of Na- and Ca-Mtm. These experimental results indicate that the adsorption of LSA on Na- and Ca-Mtm is limited within the edge surface of the Mtm particles, while the adsorption on Al-Mtm occurs at both edge and external basal surfaces.

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Carbon monoxide was oxidized with palladium chloride-active charcoal catalyst in the presence of water. Carbon monoxide was catalytically oxidized to carbon dioxide even in the absence of redox reagent such as cupric chloride. The catalyst system was assumed to be composed of the oxidation of carbon monoxide by palladium (if) chloride and palladium being further oxidized by oxygen gas with the catalytic action of active charcoal. Its reactivity was about ten times that of ethylene.
The reaction rate was well simulated by the following equation.
It resulted in the conclusions that among several complexes present in the reaction system the active complex is [PdCl₂(C0)(Fl₂O)], , or the like, and that the rate determining step is the hydrolysis of the complex to form carbon dioxide and reduced palladium. The effects of the partial pressure of carbon monoxide and steam are understood according to the mechanism mentioned above.
The reoxidation of palladium by oxygen is very fast, and consequently, it is not rate determining despite the oxidation rate of carbon monoxide is very high.

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Hydrolysis of ethyl and metyl acetates catalyzed by four types of cation exchange resins with different degrees of crosslinking was studied in a well stirred tank reactor.
Catalytic effectiveness factors and the Thiele moduli were estimated from the observed rates of reaction with different sizes of resin particles. The apparent rates of reaction were corrected for the effect of diffusion in the resins by the use of the effectiveness factors. The effective diffusion coefficients and the true rates of reaction were also evaluated. The differences in ester. concentration between swollen resin phase and bulk solution were taken into account using the adsorption equilibria measured for the esters. It was shown that the intrinsic rates of reaction thus corrected for the resistance to diffusion and the adsorption of ester by resin were independent of the degree of crosslinking.
The method of evaluating the effective diffusion coefficients from the Thiele moduli is valid when the resin particles are spherical and the active sites are distributed uniformly. This method is also useful for the direct determination of dffusion coefficients in the catalytically active H form resin.

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A new method is proposed for the measurement of zeta potential of particles dispersed in insulating solvent such as developers used in electrophotography. It is theoretically expected that the electrophoretic deposition current between two parallel electrodes and absorbance of the liquid decay exponentially during the process of electrophoresis, provided that the drift velocity of toner particles is sufficiently lower than their diffusion velocity. The transit time can be determined directly from the time constant of the decay of current or absorbance. The zeta potential of particle can be calculated from the above values of transit time and measured values of viscosity and the dielectric constant of the solvent. The other parameters of toner particles, such as mass, radius and electric charge, can also be determined. This theory has been verified by the experimental results.

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Pressure calibration and pressure distribution measurement in the sample holder were carried out on the girdle type high pressure apparatus with cone angle of 90' of both piston and cylinder, and the relation between arrangement of specimen cell and gasket assembly was discussed.
In the apparatus where the diameter of the piston tip was equal to the inner diameter of the cylinder (Fig.1), the composite gasket as shown in Fig.2-(b) was found favorable. In this case, the hydrostatic condition in the sample was almost satisfied (Fig.5). However, the considerable amounts of stresses loaded on the walls of the cylinder and the apparatus could not last so long. The fracture of the piston and cylinder was experienced (Fig.6). In the improved apparatus where the diameter of the piston was smaller than the inner diameter of the cylinder (Fig.7), the gasket shown in Fig.8-(c) was found to be the best among ones examined. Higher pressure could be attained due to intensification effect and the load on the walls of the piston and cylinder was less, although hydrostatic condition was not attained (Fig.10). This improved girdle type apparatus was able to operate sufficiently long at, pressure in the range of 15-60 kb.

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Some properties of pitch carbon were measured and were compared with those of the other carbon materials.
Pitch carbon was prepared from the variant pitch materials which take both parts of binder pitch and filler cokes of the ordinary artificial graphite.
Pitch carbon which has high breaking strength and low electrical resistivity was prepared from the variant pitch materials with low softening point, that is, with high sintering ability. The highest transverse breaking strength of pitch carbon was about 700 kg/cm², which was twice as that of carbon electrode and was close to those of the some glassy carbon. Pore size distribution of pitch carbon was also affected by the state of sintering and it exhibited the intermediate character between those of carbon electrode and Vitro Carbon (glassy carbon).
In the resistance to oxidation and thermal expansion, on the other hand, pitch carbon was similar to carbon electrode. As compared with Vitro Carbon, the coefficient of thermal expansion is greater and the resistance to oxidation is superior. Since, both pitch carbon and carbon electrode are prepared from pitch, these properties seem to be depend on the more substantial structure of carbon than the state of sintering among pitch particles.

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The thermodynamic stability constants of the complexes of pyrophosphate and triphosphate ions with Mg (II), Ca (II) and Sr (IL) are evaluated by the pH titration method. The enthalpy changes associated with the formation of the 1 : 1 complexes at 25°C are determined by a direct calorimetric method or calculated from the variation of the thermodynamic stability constants with temperature. From these values of the themodynamic stability constants and enthalpies, the corresponding entropy changes are calculated. The results are as follows (Table 2); (a) in all cases the complex formation is endotherm and entropically favored, (b) the ΔS⁰ decreases with increasing radius of the metal cations, while the ΔH⁰ does not, (c) theΔS⁰ of a triphos- phate complex is always larger than that of the corresponding pyrophosphate complex. All these results are explained in terms of present theories of metal chelate formation in aqueous solution.

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Reduction of cis- and trans-Co(N₃)₂(en)₂₊, cis- and trans-Co(N₃)₂(pn)₂, cis- and trans-CoN, (H²O)(en)22+, and cis- and trans-CoNs(H₂0)(pn)₂²₊ by Fe(II) was investigated spectrophoto-metrically under the conditions of Σ[CI0₄^-]=1.0mol/l and 25±0.1°C. The rate equation for the trans-Co(N3)₂(en)²⁺ is represented as follows:-d[Co(M)]idt=(k, + k_H+[H⁺]) [Co(ti)] [Fe(II)]. The values of le, is 9.0x 10-4M^-1.sec-1 and km-, 1.5x 10^-2 M-2.sec-i. The large increase in the reduction rate of trans-Co(N₃)₂(en)²⁺ with the hydrogen ion concentration is ascribed to protonation of trans-N3- to the bridging one in trans-Co(H₃)₂(en)²⁺; protonation of trans-N3- would reduce the free energy of activation to stretch the trans-N3- away from the Co(III) center before the electron-transfer occurs. Hydrogen ion dependence is not observed for the reduction rate of cis-Co(N3)₂(en)²⁺ under the conditions investigated. The results obtained for the reduction of cis-Co(N₃)₂(en)₂ suggest that the reaction of cis-Co(N₃)₂(en)²⁺ with Fe(II) procceds via the double bridged activated state.
The rate constant of trans-CoN₃ X(en)₂" increases in the order X=H₂O>C1->N3-. Such a reactivity pattern would mainly be caused by the difference in energy required to stretch to stretch the trans-ligand of X.

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Ammonia is converted to copper ammine complex ion when it is absorbed into cupric chloride solution. Then, by adding chromotropic acid solution into this complex ion, the color of absorbing solution changes into purplish red.
The spectrophotometric determinations were made on ammnonia by making use of that its maximum absorption wavelength is 520 nm.
It was also tested the absorption spectrum, adding amount and stability of reagents and heating time etc.
On the basis of results obtained, this method was applied to determine nitrogen in steel. By using standard sample, experimental values were found to agreed well with the standard ones.

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The photoreactions of dimethyl acetylenedicarboxylate and methyl propiolate in diethyl ether and tetrahydrofuran were studied under irradiation of ultraviolet light with a low pressure mercury lamp.
The irradiation resulted in the abstraction of α-hydrogen atom of the ethers to yield olefinic- ethers. The reactivities of the esters and ethers were discussed from the results of the quantitative analysis.
In the quenching experiment with 2, 5-dimethyl-2, 4-hexadiene for the reaction of dimethyl acetylenedicarboxylate with tetrahydrofuran, a Stern-Volmer plot gave a straight line. The sensitized reaction were carried out with sensitizers which have the various triplet excitation energies using a high pressure mercury lamp. From these results, it was found that the triplet excited state has an important role in the above reactions, and the lowest triplet ex- citation energies of dimethyl acetylenedicarboxylate, dimethyl(tetrahydro-2-furyl)fumarate and dimethyl(tetrahydro-2-furyl)malate were estimated to be 58∼59.5 and 76.3∼kcalimol, respectively.

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In the preceding paperl of this series, we reported that cis- and trans-Δ⁴-tetrahydrophthalic acic and their dimethyl esters react with benzene in the presence of aluminium chloride to produce the corresponding 1, 2, 4-trisubstituted cyclohexanes. Thus, cis-Δ⁴-tetrahydrophthalic acid [1 A] or its dimethyl ester [2 A] gives, stereoselectively, trans-4-phenyl-cis-hexahydrophthalic acid [3 A] or its dimethyl ester [4 A], respectively. Meanwhile, tran-Δ⁴-tetrahydrophthalic acid [1B] or its dimethyl ester [2 B] gives, stereoselectively, cis-4-phenyl-trans. hexahy dr ophthalic acid [3 B] or its dimethyl ester [4 B]. (Scheme 1). The present paper deals with some reactions of benzene with such compounds 4, 5-disubstituted cyclohexenes having the double. bond and a different polar substituent as trans-2-benzoy1-4- cyclohexene-1-carboxylic acid [5], its methyl ester [6], and methyl trans-2-chloroformy1-4- cyclohexene-1-carboxylate [7]. The aluminum chloride-catalyzed reactions of the [5] acid and the [6] ester with benzene gave stereoselectively t-5-phenyl-c-2-benzoylcyclohexane-r-l-carboxylic acid [8] and its methyl ester [9], respectively. Similarly the reaction of the [7] ester with benzene gave the ester [9]. The reaction is explained in terms of the interaction of lone pair electrons of oxygen in the axial carboxyl group with a vacant p-orbital of the carbonium ion which produced by protonation to the double bond of the [5, 6, 7]. Scheme 2 summaries the reaction of benzene with trans-4, 5-disubstituted cyclohexenes [5, 6, 7].

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It was shown in our previous paper that the reactions of halobenzenes with NaSH in liquid ammonia resulted in nucleophilic substitution of the halogen atoms with mercapto group.
The reaction of pentachloronitrobenzene [1] with NaSH afforded 2, 3, 4, 5-tetrachloro-6-nitrobenzenethiol and pentachlorobenzenethiol either in liquid ammonia or methanol. The yield of the products was better in the former medium.
In the reaction of 2, 3, 5, 6-tetrachloronitrobenzene [2] in liquid ammonia, 2, 3, 5, 6-tetrachlorobenzenethiol was produced by substitution of the nitro group with the mercapto group. The Cl atom ortho to the nitro group in 2, 3, 4-[3], 2, 4, 5- [4] and 2, 4, 6-trichloronitrobenzenes [5], 2, 5-dichloronitrobenzene [6] and 2-methyl-4, 6-dinitronitrobenzene [8] was more preferentially displaced by the mercapto group.
In the case of 3, 4-dichloronitrobenzene[7], p-Cl atom was easily displaced.
In the reactions of 2-[9] and 4-chloronitrobenzenes[10], the corresponding nitrobenzenethiols were formed in high yields.

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As an extension of our series of experimental studies on nucleophilic substitution reaction of halobenzenes and halonitrobenzenes with NaSH in liquid ammonia, the reactions of aromatic nitro compounds with NaSH have been investigated.
ms-Dianthryldisulfide was obtained nearly quantitatively by the reaction of 9-nitroanthracene [1] with NaSH in liquid ammonia.
The reactions of following aromatic nitro compounds with NaSH were carried out in liquid ammonia; 1, 2-dinitrobenzene[2], 1-nitronaphthalene[3], 2-[4] and 4-nitrotoluenes[5], nitrobenzene C6j, 1, 3-dinitrobenzene[7], 2-nitroaniline[8], 4-nitrophenetole[9] and 4-nitrobiphenyl [10].
The results are summarized as follows.
1) In the reaction of [2], 2, 2'-dinitrodiphenyldisulfide was obtained.
2) In the reaction of [3], 4, 4'-dinitrodinaphthyldisulfide and 4, 4'-diaminodinaphtyldisulfide were obtained.
3) The methyl group was oxidized and the nitro group was reduced in the products of the reactions of [4] and [5].
4) In the reactions of aromatic nitro compounds such as [6], [7], [8], [9] and [10], the corresponding substituted aniline and substituted azobenzene were preferentially obtained.
The reaction mechanism are discussed.

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As an extension of our studies of the nucleophilic substitution and oxidation-reduction reactions of the aromatic compounds with NaSH in liquid ammonia, we investigated the reactions of aromatic nitriles with NaSH.
The reaction of benzonitrile with NaSH and NH₄C₁ in liquid ammonia was quite similar to the reaction with H2S and gave thiobenzamide in high yield.
In the absence of NH₄Cl, the reaction of benzonitrile with anhydrous NaSH in liquid ammonia gave thiobenzamide inefficiently, but with the use of aqueous NaSH, benzamide was given efficiently.
Benzonitrile did not react with H₂o in liquid ammonia.
In the presence of NH₄Cl, the reactions of cyano phenols and their tosylates with NaSH were carried out in liquid ammonia, and the corresponding thiobenzamides were obtained.
The reaction of p-chlorobenzonitrile with NaSH in liquid ammonia in the presence of NH4C1 was found to give p-chlorothiobenzamide and the products in which the chlorine atom had undergone the nucleophilic attack.

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The deep blue pigments formed by the reaction of o-acylbenzophenones with ammonia are stable and were found to be meso-alky1-5, 5'-dipheny1-3, 4; 3', 4'-dibenzo-2, 2'-pyrromethenes [1] by one of the authors. However, the pigments formed by the reaction of o-acylbenzophenones with primary amines are generally unstable and their structures can not be explained similarly.
In benzene, o-acetylbenzophenone gave with cyclohexylaniine in the presence of acetic acid a stable blue crystalline pigment, C₃₅H₂₉N0(mp 217°C). On the basis of its spectra and chemical behaviors this pigment was determined to be 2-[2-cyclohexy1-3-pheny1-1-isoindoly1]-3-phenylindone[3] and its formation mechanism was proposed.

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The partial benzylation of 3-methoxy-2, 4, 6-trihydroxy-acetophenone [3] was investigated. The reaction products were purified on silica gel column chromatography with chloroform. The separated compounds were identified as 4, 6-dibenzyloxy-2-hydroxy-[4] (mp 140∼441°C), 2, 4-dibenzyloxy-6-hydroxy-[5] (mp 70%sim;71°C), 5-benzy1-2, 4-dibenzyloxy-6-hydroxy-[6] (oil) and 2, 4, 6-tribenzyloxy-[7] (oil)-3-methoxyacetophenone on the basis of NMR spectra (Table 1).
By the Baker-Venkataraman transformation, 5-benzy1-2, 4-dibenzyloxy-6-hydroxy-3-methoxyw-(acyl)acetophenones [9] were obtained from CC and substituted benzoyl chloride, via the corresponding benzoyl esters. The cyclization of the acetophenones [9] with sodium acetate in acetic acid could afford 8-benzyl-7-benzyloxy-5-hydroxy-6-methoxyflavones [12] (Table 7). The hydrogenolyses of the flavones [12] yielded the desired 8-benzy1-5, 7-dihydroxy-6-methoxyflavones [13] (Table 8).
The UV and NMR spectra of these flavones have been discussed (Table 3, 4 and 5).

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Adducts of 1-benzoy1-2-ferrocenylethylene [1], a chalcone analog of ferrocene, with pentane-, benzene- and p-toluene-thiols, have been synthesized. Comparison of the nmr spectra of these adducts [2, a∼d] with those of the corresponding adducts of chalcone [3, a∼d], Fc replaced by Ph in [1], revealed some interesting regularities. The difference in the chemical shifts of the a-protons between [2] and the corresponding [3], Δτα=ταFe-τβPh, was found to be 0.05∼0.17 ppm, while that in the -protons, Δτβ=τβFe-τβPh, was -0.13∼ -0.15 ppm for aliphatic thiol adducts, and 0.06∼0.04 ppm for aromatic thiol adducts (Table 2). The results are tenta- tively explained in terms of weak intramolecular bonding between iron and sulfur atoms in thiol adducts [2, ad].

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Previously, one of the authors difined the percentage fixation of reactive dyes and proposed its new simple measuring method.
In this study the definition and the measurement of this fixation were examined from the point of view of dyeing chemistry.
The whole dyestuffs on the dyed cloth were assumed to consist of the dyestuff (Φ) adsorbed in the interior of fibre by the substantivity of dye and the dyestuff (σ) merely attached on the fibre. Both quantities, Φandσ, were measured separately and the results were discussed. The results are summarized as follows:
1) The results calculated by Eq.1 are similar to the true percentage fixation.
2) The presence of urea decreases the quantity of c6, but increases the contribution from the a-part.

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When the thermal polymerization of vinyl bromide was carried out, the dehydrobromination always occurred competitively. Example, when the thermal polymerization was carried out for 60 minutes, the formation of double bond was 2.70, 4.80 and 5.25 mole % at 40°, 50° and 60°C, respectively. The emulsion polymerization of vinyl bromide without occurring dehydrobromination was studied. When it was carried out using Fe-H₂O₂ system as initiator, the yield of polyvinyl bromide was 10 weight percent for 4 hours. But being used Fe-H₂O₂ascorbic acid system as initiator, it was 94.0 weight percent for the same reaction times and the dehydrobromination was not almost recognized. Emulsion polymerization being compared to bulk one, the polymerizability of vinyl bromide was studied and the monomer reactivity ratios were gained as follows.

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The effect of oxygen on the polymerization of acrylonitrile(AN) initiated by ceric ion was investigated. The results obtained are as follows: 1) Ceric salt initiates the polymerization of AN after some induction period in the presence of oxygen in aqueous solution, and the yield of polymer increases with increasing oxygen content(Fig.2, Fig.3).2) The oxygen in aqueous solution is almost consumed during induction period(Fig.6).3) The ceric ion in aqueous solution is not consumed by monomer during induction period, but begins to decrease its concentration after the initiation of polymerization(Fig.7).
From these results, oxygen in water was found to take part in the initiation of polymerization, and it is assumed that oxygen reacts with monomer in the presence of ceric salt to form primary radical.

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The apparent activation energy of cellulase-hydrolysis reaction of fibrous cellulose in heterogeneous system was estimated by the temperature dependence of the maximum velocity of the reaction. The maximum velocity was derived from the Hofstee plots using the rate of glucosidic linkage splitting, which was theoretically calculated from the weight loss of sample.
The values obtained in such method were in a range of 5.4-8.9 kcal/mol, depending upon the reaction conditions such as reaction time, shaking condition, swelling capability and sort of cellulose samples, while Whitaker reported the values 11.9-12.7 kcal/mol for oligoglucoside.
The values obtained in the present study are markedly lower than 29.8 kcal/mol for acidhydrolysis, and suggest the characteristics of enzyme reaction clearly. It is believed that the fluctuation of the values is originated in the difference in the structural factors as well as in the chemical composition of the samples, although the structural factors mentioned here have a different meaning from the one in acid-hydrolysis, as previously reported.

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A few factors which affect the accuracy of the determination of molecular weight and its distribution of phenolic resins were discussed. For the purpose of improving the accuracy, a new calculation method for molecular weight is proposed. The method can be applied to discontinuous GPC curves of phenolic resins, epoxy resins and other thermosetting uncured oligomers. The net peak area which corresponded to the dimer fraction was obtained by integrating the peak area from the middle point between the monomer peake and the dimer peak to the middle point between the dimer peak and the trimer peak. Similarly, the net peak areas of a trimer, a tetramer, a pentamer and so forth can be obtained in the same way as above.
The other successive calculation procedures for molecular weight determination were the same as taken for GPC curves of such polymer as polyethylene. Pore sizes of polystyrene gels were 5000-45000A, 700-2000A, 350-700A and 50-80A. Tetrahydrofuran was used as carrier solvent at room temperature. The flow rate was 1 ml/min.
Mw was found more available than Mn as the cure index of phenolic resins because of its high sensitivity to high molecular weight fractions. The range of polydispersity (Mw/Mn) of phenolic, p-terbutylphenolic and p-phenylphenolic novolac resins was between 1-2, and Mw/Mn of fractions by the solvent fractionation method was between 1.12 and 1.36 to 1.44 of the original resin.
Furthermore, it was found that a small amount of molecular weight fraction above 5000 exists in uncured phenolic novolac and resole resins.

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Effect of aluminium phosphate (AP) on defluorinating-reaction of fluorapatite (FAp) was studied. The decomposion rate of FAp and its fluorine volatility were measured under several atmospheres and various heating conditions.
The decomposition was active above 1050°. The decomposition reaction was more preferable to the volatilization reaction in a nitrogen atmosphere, whereas the rate of above reactions were nearly equal in nitrogen-water vapor atmosphere. In the FAp-AP-H₂O system, H₂O acted to accelerate the decomposition and the volatilization. On the other hand, when SiO₂ was used in place of AP, SiO₂ itself was considered to accelerate the above reactions.

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New metal monothiobenzoates SnL₄ (where HL is monothiobenzoic acid) as well as SbL₃ have been synthesized. The former was obtained from tin (IV) chloride and potassium monothiobenzoate in an absolute ethyl alcohol medium. The same complex was also obtained by the reaction of free monothiobenzoic acid with tin (IV) chloride. The latter, SbL₃, was obtained from antimony (III) chloride as well as antimony (V) chloride and potassium monothio- benzoate or the free acid. Sn(II) and Sb(V) complexes were not yet obtained. This fact is probably due to the higher stability of the Sn(V) and Sb(II) complexes when compared with the Sn(II) and Sb(V) ones, respectively.
In these complexes, the ligand coordinates to the central metal ion only through the sulfur atom as shown in the Hg(II), Cu(I) and Ag(I) complexes of the ligand. The infrared spectra of the products were shown and discussed.

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Separation behavior of positional isomers of alkylbenzenes was studied by gas liquid chromatography with liquid crystals, 4, 4'-dimethoxyazoxybenzene and 4, 4'-diethoxyazoxybenzene, as stationary phases.
It was found that the separation of m- and p-isomers of dialkylbenzenes, in the nematic state of liquid phases, depends upon the polarity of alkyl groups in the alkoxy group of liquid phases, the separation of o- and (m, p)-isomers depends slightly upon the polarity of them and the separation behavior of mono-alkylbenzenes with long alkyl group is the same as that of p-dialkylbenzenes which have the same carbon number in the side chain.

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Methyl methacrylate is polymerized by the addition of carboxylates of Cu(II), Sn(II), Ni(II), Co(II), Zn(II), Mn(11), and Al(III). The catalytic activity of the carboxylates is found to be low in benzene solution, but appreciably high in cyclohexanone solution. Addition of CCl⁴ into polymerization systems in the presence of carboxylates of Mn(II) and Al(III) increases remarkably the polymer yield. The chelating agents such as 1, 10-phenanthroline and 1, 1'- dipyridyl activates the carboxlates of Ni(II) and Cu(II). Acetylacetone increases the functions of polymer yield in the presence of carboxylates of Ni(II), Co(II), and Mn(II). Benzoic acid accelerates the polymerization of styrene in the presence of tris(acetylacetonato)Mn(III).

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Catalytic activity and surface area of powdered tantalum monocarbide(TaC) evacuated under high vacuum (∼10^-5 mmHg), were investigated as a function of the evacuating temperatures between 400 and 1100°C. It was found out that the conversion activity for hydrogenation of benzene was negligibly small at the lower evacuation temperature than 900°C; the sample was, however, abruptly activated when it had been evacuated at above 1000°C, and that the surface areas measured by BET method using krypton, were nearly constant (1.5 m²/g) regardless of the evacuating temperatures. These results suggested that the activation created catalytically active sites on the surface.

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