The viscosities of aqueous solutions of biguanide (amidinoguanidine) salts and their alkyl and aryl derivatives were measured at relatively low concentrations at various temperatures and analysed by Jones-Dole equation. As shown in Table 3, the ionic B-coefficients (B_ion = B_st + B_size) of all these cations had the positive values. However the value of B_st, the increment of B-coefficient of an ion associated with the change of water structure, were slightly negative for biguanide ion and largely positive for the substituted biguanide ions. B_size is the increment of B-coefficient arising from the shape and size of an ion, and evaluated from Einstein's viscosity equation for a particle. The contributions of these cations to the activation energy of viscous flow, E₊* were small positive value for biguanide ion and large positive values for the substituted biguanide ions as shown in Table 5. From these results, it was concluded that biguanide ion was neither a structure maker nor a stucture breaker, wheile the substituted biguanide ions the structure makers. Concerning the protein denaturation, the order of protein denaturation abilities among b iguanide salts with different anions parallels the order of structure breaking abilities among them as shown in Table 2 and 6. Among the hydrochloride of guanidine derivatives, the protein deaturating abilities decrease in the order N-butylbiguanide ion > biguanide ion > guanidinium ion, which is reverse to the case of structure breaking abilities. These results suggest the importance of direct interactions between protein and salts on protein denaturation in aqueous solutions.

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The intermolecular hydrogen bond of phenol (PhOH) and methyl p-toluenesulfonate (MPTS)in carbon tetrachloride solution was quantitatively studied by use of IR spectroscopy.
In the PhOH-CCl₄ system, the free OH stretching vibration band, v_OHf, shifts from 3615 cm^-1to 3490 cm^-1 by the addition of excess amount of MPTS and a new band appears at 1335 cm^-1. The absorbance of this new band increase in the absorbance at 3490 cm^-1 assigned to the hydrogen bonded PhOH, and the absorbances of antisymmetric-stretching vibration band of S=0 (1376 cm^-1) decreased (Fig.3). From these relations, the band at 1335 cm^-1 was assigne d to the hydrogen-bond-interaction band of S=O. Wave number shifts, Δ v_OH and Δ v_as s=o, were estimated to be 126 cm^-1 and 41 cm^-1, respectivery.
The step-wise equilibrium constants ware calculated on the assumption that the association of PhOH in carbon tetrachloride solution is represented by the reaction formula, (PhOH)_n-1+ PhOH ↔ (PhOH)_n, and that the step-wise equilibrium constants are given by K_n=[(PhOH)_n]/ {[(PhOH)_n-1] · [PhOH]}. The concentration of free PhOH and dimer we re estimated from absorbance at each absorption band (3615 cm^-1 and 3490 cm^-1 respectively). In a dilute solution, the trimer concentration can be estimated by the following equation, [trimer] =1/3 [PhOH]_t([free Ph0H] 2[dimer]).
In this way, the calculated step-wise equilibrium constants, K₂ and K₃, are 0.86 ± 0.02 l· mol^-1and 2.49 ± 0.26l · mol^-1, respectively.
For the PhOH-MPTS-CCl₄ system, the calculation of the equilibrium constant was carried out on the basis of the fact that only the 1: 1 complex was formed under the condition of [MPTS] ≥ [PhOH]. The concentration of each chemical species was determined from the number of hydrogen bonded OH, and the concentration of free PhOH was calculated by taking into account the associatian constant of PhOH in carbon tetrachloride solution. The step-wise equilibrium constant thus calculated was 5.55 ± 0.28l· mol^-1.

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The effect of hydrogen on propylene polymerization with TiCl₃-Al(C₂H₅)₃ is studied. The following results are obtained from the polymerization rate and the isotacticities and the molecular weights of the polymers produced in the presence of hydrogen.
The polymerization rate decreases with hydrogen pressure as e xpressed by
where, R_∞^H, and R_∞^O are the stationary polymerization rates in the presence and in the absence of hydrogen, respectively. The apparent activation energy of a was negative. We propose a reaction mechanism which contains the recovery of polymerization centers deactivated temporarily by the adsorption of hydrogen. This recovery needs cocatalyst, Al(C₂H₅)₃, and propylene. The transfer rate obtained from the molecular weight of polymers supports the above reaction mechanism.

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Metathesis of isobutylene with 2-butene and disproportionation of propylene were studied over the supported rhenium oxide catalysts using both flow and pulse reactor techniques. By the metathesis of isobutylene with 2-butene over Re₂O₇-Al₂O₃₂ catalysts containing, various amount of rhenium oxide, a satisfactry amount of isoamylenes was obtained. The maximum activity was observed in the range from about 5% to 7% Re. The rate of isomerization between cis-2-butene and trans-2-butene is very fast and the mechanism of this reaction over these catalysts was assumed to be the same as that of metathesis.
With rising pretreatment temperature of the catalysts, more water is desorbed through two steps from the surface of the catalysts. At the first step of water desorption, the active site for the polymerization of propylene appears and at the second step which is accompanied by oxygen, the active center for polymerization disappears and that for the disproportionation appears. On the other hand the activity for disprotionation of propylene over a Re₂O₇-SiO₂catalyst is relatively high even at such a low pretreatment temperature as 150°C.
From the above results it was considered that the active center for the olefin metathesis exists in slightly reduced Re ion and the acid site on the carrier is not concerned with the reaction directly.

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The surface acidity of MoO₃-Al₂O₃ catalysts containing 1-63 wt% MoO₃. was measured by butylamine titration using H₀ indicators and by adsorption of NH₃, pyridine and quinoline.
The acid strength of the catalysts containing more than 27% MoO₃ was distribut ed from H, 6.8 to 3.3, while stronger acid sites (H₀<-3.3) were observed on the catalysts containin g less than 12.5% MoO₃. The amounts of NH₃ adsorbed at 200° and 300°C on the catalysts containing more than 27% MoO₃ agreed with the numbers of acid sites at H₀ 3.3 and 1.5determined by amine titration.
Two types of adsorb ed basic molecules were found on the catalysts at 200°C; ( I ) the one was reversibly adsorbed molecule which was easily removed by evacuation at 10^-5 mmHg, and 00 the other was irreversibly adsorbed molecule which was retained on the evacuation. When the catalysis were pretreated with H₂ or H₂S, the amount of irreversibly adsorbed basic molecules increased.
The surf ace structure of the catalysts for these two acidic sites are discussed.

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The hydrogenolysis of pentane, hexane, heptane, and octane on nickel-alumina catalyst was studied in a flow system under hydrogen pressure of 10 atm and at the temperature ranging from 250° to 350°C.
The predomin ant reaction was successive degradation to methane and a hydrocarbon of o ne carbon atom less than the starting hydrocarbon. The probuct contained also relatively small amount of lighter hydrocarbons such as ethane and propane.
Distributions of products in the hydrogenolysis of heptane was studied with respect to the gas flow velocity. Mole fraction of hexane in product was decreased and that of pentane was increased with contact time, and those of ethane, propane, and butane were almost constant (Fig.3).
Rela tive amount of methane to other products given by
was estimated as 1.48 (pentane), 1.15 (hexane), O.97 (heptane), and O.68 (octane) at 260°C (Fig.4), where n is the carbon number of reactant and C_i is yield of the component contai ning i carbon atoms in product. The results sugge st a mechanism involving three types of hydrogenolysis reaction; a splitting of terminal carbon-carbon bonds to give methane and hydrocarbons of one carbon atom less than the starting hydrocarbon ( I ), a total fragmentation of an adsorbed molecule to give methane as the only product (II), and a rupture of other carbon-carbon bonds than terminal to give lighter hydrocarbons (III).
Reaction (II) was decreased, w hile reaction (III) was increased with the carbon number of the reactant.

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The cathodic behavior of manganese dioxides electrodeposited on graphite rod was studied in LiClO₄-propylene carbonate, dimetyl sulfoxide, tetrahydrofuran and γ-butyrolactone by means of potential sweep and galvanostatic method.
Upon heating at about 200°C in an air, the manganese dioxide electrode gives the most distinct cathodic peak current on polarization curve and a single plateau potential on discharge curve corresponding to the reduction of oxide toward lower oxidation state. The polarization curve is also cosiderably influenced by the viscosity of organic solvent.
The apparent discharge efficiency decreases with increasing thickness of the manganese dioxide layer deposited on the graphite and with increasing discharge current. The manganese dioxide is very slightly soluble in those organic electrolytes in the discharged state. Results showed that the manganese dioxide seemed to be reduced in the solid state.

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Flow rate disturbance of carrier gas at a column outlet, which sometimes perturbs the quantitative analysis, were measured using a orifice type flow meter. In order to avoid the viscosity effect of sample vapor, a long delay tube was connected between the column outlet and the orifice. Pressure fluctuations due to the flow rate disturbance was recorded on a strip chart recorder by means of a diaphragm type pressure transducer and associated electrical circuits.
When helium was used as a carrier gas, flow rate increase caused by (1) an initial surge due to sample introduction, (2) a decrease of the viscosity of gas inside the zone and (3) emergence of vapor from the solution in the column, was observed in the order for benzene, but the increase caused by the three factors was observed evenly for diethyl ether.
Maximum increase in flow rate was reached up to 6% for benzene (1μ;l) using PEG 20 M column (2 m) at 120°C.
For a mixture of ethyl methyl ketone and octane, a fluctuation of flow rate was observed as a sum of individual fluctuation of single runs.
When the special column, where the stationary liquid phase gradually decrease from the column inlet to the outlet, was connected to the outlet of main column in order to decrease the perturbation on quantitative analysis, the increase in flow rate caused by the factor (3) can be reduced.

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Substituent effects on the absorption and fluorescence spectra of coumarin derivatives have been investigated in various solvents. No absorption band attributed to nπ* transition is observed. However, its existence is suggested from the fact that coumarin is non-fluorescent. As the electron donating tendency of the substituent at 7-position increases, the wave number of the first absorption band decreases and the amount of solvent shifts increases. These observations indicate that the first excited singlet state or the fluorescent state has a character of the intramolecular charge transfer (CT) state arising from an electron transfer from the substituent to the coumarin skeleton. Coumarin itself is non-fluorescent. However, coumarin derivatives having an electron donating group at 7-position are fluorescent. The relative fluorescence yield becomes higher with the increase in the electron donating tendency of the substituent. Since nπ* state is not so much affected by the substituent, the above results lead to the conclusion that an increase in the energy gap between nπ* and ππ* state enhances the fluorescence process. Effects of the solvent and temperature on the relative fluorescence yield are also discussed.

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Four secondary hydroperoxides with six-membered rings, i, e., cyclohexyl hydroperoxide, 2-chlorocyclohexyl hydroperoxide, 2-tetrahydropyranyl hydroperoxide and 1, 4-dioxanyl hydroperoxide, were prepared and subjected to thermal decomposition in benzene. The first order rate constants, the activation energies and entropies were determined. Then the relationship between their structures and these kinetic date were examined.
The examination of the IR and NMR spectra of these hydroperoxides reveals that cyclohexyl and 2-chlorocyclohexyl hydroperoxides have equatorial hydroperoxy groups whereas 2-tetrahydropyranyl and 1, 4-dioxanyl hydroperoxides have axial ones. Intermolecular hydrogen bonding is greatly reduced in such dilute solutions as those used in our experiments and no intramolecular hydrogen bonding is present in the solution of 1, 4-dioxanyl hydroperoxide. The dissociation energies of the O-O bonds of these hydroperoxides were found to be nearly the same and 30 kcal/mol and do not depend upon the number of oxygen atoms, their positions in the ring and the conformation of these hydroperoxides molecules.
1, 4-Dioxanyl hydroperoxide decomposes extremely faster than other hydroperoxides and the activation entropy is positive. It could be explained in terms of the repulsion between oxygen atoms of the axial hydroperoxy group and those of the 1 and 4-position in the 1, 4-dioxane ring.

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By the reaction of iodoform with dialkylzinc [4] in benzene, alkyl iodide [5], tropilidene [6], 7-alkyltropilidene [7], and two olefins ([8] and [9]) (Scheme 1 and Table 1) were obtained. Olefin[8] has the same number of carbon atoms as the alkyl residue of [4], and olefin [9] has one more carbon atom than that of [4]. The relative amounts of [6] and [7] are considerably influenced by the structure of [4] used: diethylzinc [4 a] gives chiefly [7a], whereas diisobutylzinc [4 d] gives [6] as a major product. Alkylzinc iodides are also effective for the benzene ring expansion originated from the iodocarbenoid reaction (Table 2). Methylzinc iodide gives 7-methyltropilidene only, and [6] is not detected in the reaction mixture.
The mechanism of the formation of [6] from benzene by the iodocarbenoid reaction was discussed in terms of the fact that [6] and olefin [8](R¹R¹C=CH₂), which has the same number of carbon atoms as the alkyl residue of C 4D (R¹R²CH-CH₂-Zn-), are formed in almost equal yields. A direct reduction mechanism of the intermediate tropylium iodide by alky lzinc species was proposed, in which β-hydrogen was transferred as hydride from alkylzinc compound to tropylium ion intermediate (eq. ( 5)).
Ring expansion of alkylbenzenes due to iodoform and dipropylzinc was also studied (Table 3). Formation of [9] was explained as follows: the insertion of iodomethylene group, originate d from the idocarbenoid reagent, into alkyl-zinc bond afforded alkylcarbenoid [11] and then [11]transferred to [9] via 1, 2-hydride shift (eq. ( 6 )).

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In order to produce half ester salt type surfactant, phthalic and maleic half esters were synthesized with primary or secondary higher alcohols. Conversion rate of the reaction, acidities of the half esters and the properties of their sodium salts were studied.
In the equimolar reaction of alcohols with maleic anhydride at 1l4-115°C for 15 hr, over 90% of conversion was obtained on all alcohols examined.
The acidity of the half ester was enhanced by connecting carboxyl group with ester group through phenylene or vinylene group. The pK_a values of maleic derivatives were smaller than that of lauric acid by 1.50-1.79 units.
Sodium salts of phthalic and ma leic half esters derived from C₁₂ and C₁₆ alcohols (secondary and primary) reduced the surface tension of aqueous solution to about 30 dyne/cm. Critical micelle concentration depended upon the substitution position of hydroxyl group of alcohol. As to hexadecanol esters, for instance, cmc values were; 1- and 2-isomers: 0.3 x 10^-3, and 8-isomer: 1.0x10^-3 for maleic esters, and 1 and 2-isomers: 0.3 x 10^-3, and 8-isomer: 3.Ox 10^-3 mol/l for phthalic esters.
Hard water stability of sodium salt of half ester was situated between those of sodium dodecylbenzenesulfonate and sodium myristate, and was considered to be improved tolerably.
Sodium alkyl maleate was found to be less stable to hydrolysis of the ester g roup in an aqueous solution compared with sodium alkyl phthalate, which was quite stable under the same conditions.

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The interaction of nonionic dyes with sodium poly (styrene sulfonate) (PSSNa) was investi gated by means of solubility measurement and equilibrium dialysis. The solubilities of p- aminoazobenzene (PAAB) and naphthalene (NA) increase in the presence of PSSNa. The increase in solubility depends on the degree of sulfonation (D. S.) of the polymer but is independent of the molecular weight when its value is above 9 x10⁴ (D. S. =100%). The smaller the D. S., the larger becomes the solubilization. The solubilizing effect of PSSNa is remarkably larger than those of sodium p-ethylbenzenesulfonate (EBSNa) and sodium p-toluenesulfonate (PTSNa), and the effect is enhanced by the presence of NaCl. In the case s of EBSNa and PTSNa, the addition of NaCl brings about salting out. The solubilities of PAAB and NA in aqueous PSSNa solution increase linearly with concentration of PSSNa and the tendency accords with the results of equilibrium dialysis.
The thermodynamic quantities of trans fer of PAAB from water to the aqueous solutions of PSSNa and aromatic sulfonates are ΔH_tr < 0, ΔS_u.tr < 0, and ΔH_tr > 0, ΔS_u.tr > 0, respectively.
It was suggested that the interaction between PAAB and PSSNa could be inte rpreted in terms of partition of PAAB between polymer and aqueous phase similar to the dyeing system of nonionic dye and polymer. The mechanism of solubilization of PAAB in the presence of PSSNa and PTSNa was explained in terms of an exothermic interaction of PAAB with the PSSNa moiety and of an entropy contribution due to the water structure change.

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Catalytic actions of HgSO₄ and PdSO₄ for the sulfonation of anthraquinone with SO₃ were studied by using sulfolane in place of sulfuric acid as a solvent.
Reactions were carried out under the conditions free fr om moisture. Products were analyzed by high speed liquid chromatography.
In the presence of HgSO₄, oleum gave considerable amounts of by-products (Fig.1 a), whereas, SO₃-s-ulfolane system gave almost wholly α- and β-monosulfonic acids and only trace amounts of the by-products such as disulfonic acids (Fig.1 b). But the value of [α / (α+β)]x100 was ca.80% at the most, indicating that HgSO₄ also accelerated the formation of; 3-sulfonic acid (Fig.2 b and 1 b). Moreover, the isomerization of α-sulfonic acid to β-sulfonic acid was observed by prolonged heating (Fig.1 b and 3).
The result with still higher value of [α / (α+β)] x 100 (more tha n 97%) and less by-products was attained by using PdSO₄-sulfolane complex (Fig.2a). In this case the selectivity was not affected largely by the reaction temperature. The optimum ratios of SO₃/anthraquinone and PdSO₄/anthraquinone in order to achieve the high value of α / (α+β) and to avoid the formation of the by-products were ca. 0.5-1.0 (mole ratio) and 2-3 wt%, respectively (Fig.5).

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The intrinsic birefringence of nylon 6 crystal (Δ_c⁰) was estimated by means of theoritical calculation and experimental extrapolation.
The theoritical calculation of Δ_c⁰ was carried out in a usual way using the values of bond polarizabilities according to Bunn et al. and the atomic arrangements in the crystal according to Holmes et al. The calculated value of Δ_c⁰ is 94.4X10^-3.
The experimental extrapolations based on the assu mption of two-phase model composed of crystalline and amorphous phases and the additivity of birefringence, viz., total birefringence is the sum of the orientation contributions of crystalline and amorphous phases and of form birefringence. Poorly and highly oriented specimens were used for the experimental extrapolation. The value extrapolated by the use of poorly oriented specimens is ca. 30 x 10^-3, which is too small to be ascribed to Δ_c⁰. The value extrapolated by the use of highly oriented specimens is 78 x 10^-3, which is the most reliable value among the results obtained in the present investigation.
Also, the problems concerning with these theoritical and experimental procedures were discussed.

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Polypropylene resin composites, consisting of cation exchange resin particles (the diameter was less than 149, μ) and finely dispersing in polypropylene matrix, were formed into sheets. By treating the above sheets with hot water, the heterogeneous cation exchange membranes of good electrical and mechanical properties were obtained. The effects of crosslinking and particle diameter of cation exchange resins on the heterogeneous cation exchange membrane properties were investigated in detail. The higher the degree of crosslinking of cation exchange resins, the larger are the ion transfer coefficient and the specific resistance of the heterogeneous cation exchange membranes. On the other hand, the smaller the particle diameter of cation exchange resins, the lower is the specific resistance. These, phenomena were explained in terms of the presence of cavities which are formed between cation exchange resin particles and the polypropylene matrix by the hot water treatment. It was concluded that the preferable cation exchange resins to obtain the better heterogeneous cation exchange membranes are those whose degrees of crosslinking are as high as possible and whose particle diameters are as small as possible.

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The polymerization of isoprene by means of catalyst systems consisting of titanium alkoxide and organoaluminum compound was studied in benzene solution. Effects of synthetic conditions of several catalysts on the yield, the microstructure and the molecular weight of the polymer were investigated.
In the case o f titanium tetrabutoxide [Ti(OBu)₄], the cis-1, 4-polymerization occurs in the presence of diethylaluminum chloride [AlEt₂Cl] or ethylaluminum sesquichloride as [AlEt_1.5Cl_1.5] a cocatalyst.
Besides, when butoxytitanium chloride combines with organoaluminum compound having appropriate numbers of chlorine atom, it showes an activity for the cis-1, 4-polymerization. In conclusion, the present results suggested that the optimum Cl/Ti mo le ratio for the cis 1, 4-polymerization of isoprene remains constant being 9-12, although the optimum Al/Ti mole ratio changes in each catalyst system.

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The oligomerization of isoprene and its simultaneous cis-1, 4-polymerization occur by the use of titanium tetrabutoxide [Ti(OBu)₄]-diethylaluminum chloride [AlEt₂Cl] catalyst system. On the basis of gaschromatography and infrared spectrum the dimers of isoprene obtained were found to be the same as those obtained by the use of TiCl₄-Al (i-Bu)₃, catalyst system. Thus, 2, 6-dimethyl-1, 3, 6-octatriene[1] is a chain dimer and 2, 4-dimethyl-4-vinyl-1-cyclo hexene[2] is a cyclic dimer and these are the main products.
The rate equation of the dimerization of isoprene is shown below:
Despite the variation of Al/Ti mole ratio in the catalyst system, the[1]/[2] ratio is constant. The dimerization of isoprene is inhibited by the addition of 2, 2'-bipyridyl, which acts as a bidentate ligand. On the basis of the above mentioned facts, it was assumed that the dime rization of isoprene proceeded in terms of the bimolecular reaction between the isoprene monomers coordinated unidentately and/or bidentately on the same Ti active species.

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Polymerization of butadiene initiated by lithium alkylamide (LiNR₂) was studied. The polymerization does not occur with LiNR, in hydrocarbon media, but the reactivity of LiNR₂ increases markedly in the presence of hexamethylphosphoric triamide (HMPA), which initiates the 1, 2-polymerization of butadiene.
By adding three moles of HMPA to one mole of LiNR₂, the exothermic polymerization occurs and 88-89% of polybutadiene has 1, 2-structure without cis-1, 4-structure.
It was found that the microstructure is independent of the amount of HMPA and a type of amides added. An approximate linear relationship exists between the logarithm of the amount of catalyst and that of the polymer viscosity. After polymerization of butadiene, when styrene is added to the polymerized mixture, butadiene styrene block copolymer is formed. From these results, this polymerization would proceed by means of the mechanism of living type.

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A novel reaction of polybutadiene with vinyl substituted aromatic hydrocarbons, e. g., styrene and bromine compound, e. g., t-butyl bromide, was studied at 120-460°C under the condition of unquenched state of nickel catalyst after polymerization of butadiene. The polybutadiene was obtained by using nickel organic compound/boron trifluoride etherate/trialkylaluminum catalyst system. This reaction brings about an increase in molecular weight and in Mooney viscosity of polybutadiene and is called “Molecular weight jump reaction”.
The mode of the reaction varies with the concentration of nickel catalyst, vinyl substituted aromatic hydrocarbon and bromine compound as well as reaction temperature and the reaction does not occur when any of the above substances is not present. If a compound of chlorine or iodine is used instead of that of bromine, the reaction does not occur or gives a gelled polymer. When butadiene monomer is present, the reaction is retarded.
The resulting products, having Mooney viscosity by a factor of about two or three than that of the starting polybutadiene, are consist of almost linear polybutadienes containing trace or small amount of vinyl substituted aromatic hydrocarbon unit, give no gel and are suitable for industrial material after oil extending.
As is shown in the molecular weight distribution curve, the resulting products has wider high molecular weight region than that of the starting polybutadiene and the heterogeneous jump reaction in this high molecular weight region might presumably occur.
It was also assumed that the reaction proceeded in terms of radical coupling of styryl radicals attached to the ends of polybutadiene catalysed by active nickel.

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New acylation reagents, 4-acetyl-2-phenyl-1, 3, 4-oxa- and thia-diazolin-5-ones and -thiones [6 a-d], prepared by the reaction of 2-phenyl-1, 3, 4-oxa- and thia-diazolin-5-ones and -thiones [5 a-d] with acetic anhydride in reasonable yields, were allowed to react with various amines at room temperature to give the corresponding amides quantitatively. The aminolyses of [6 a-d] by cyclohexylamine indicated that [6 a-d] are 10²-10⁷ times more reactive than p- nitrophenyl acetate, and thiadiazolines [6 c, d] are 4-50 times more reactive than corresponding oxadiazolines [6 a, b] and thiones [6 b, d] are 10³ -10⁴ times more reactive than corresponding ones [6 a, c]. Existence of linear relationship between log k₂ and the wave number of acetyl groups (v_c=_o) of [6 a-d] was confirmed. Further, 4-leucyl derivatives [11 a, b], obtained from [5 a, b] and Z-LeuOH, were allowed to react with HGlyOEt to give non-racemized Z-Leu-GlyOEt almost quantitatively. The polymers [14], [20] containing [ 6 ] structure were found to be useful polymeric reagents for acylation.

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For an ettective utilization of plastic wastes, thermal gasification of polypropylene was carried out under atmospheric pressure by using a flow system of fixed bed reactor, in which the overheated steam was introduced as a heat carrier.
Pyrolysis conditions were; temperature, 500-650°C; residence time, 1.3-2.7 sec; steam to polymer dilution ratio by weight, 0-3.1.
Gasification easily proceeded even in the range of relative low temperatures and large amounts of olefins containing mainly propylene were obtained.
Under the conditions of residence time, 2.7 sec and steam di lution ratio, 3.1, the maximum propylene amount of about 26 wt% was attained at 600°C, and the total amount of ethylene, propylene and isobutylene of about 40 wt% as well as the total gas amount of about 65 wt% were obtained at 650°C.
In thermal gasifi cation of polypropylene using overheated steam, the reaction temperature is an important operating factor and the amount of product is largely affected by residence time. However, an increase in steam dilution ratio is not so important. Therefore, operating factors are limited to reaction temperature and residence time.

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Studies on gasification of polypropylene under atmospheric pressure have been carried out by using an apparatus consisting of a flow system of fixed bed reactor, into which the overheate d steam was conducted as a heat carrier.
In this study, by making an experimental equation of intensity function (I_F) concerning pyrolysis conditions, the product yield was estimated.
I_F is dependent only upon reaction temper ature and residence time and is expressed by the following equation: I_F=Tθ^0.05 with reference to methane, where θ is the residence time (sec), T is temperature (°F) and methane is assumed to be a final product of pyrolysis.
As I_F correlates with product yields (as shown in Figs.4, 5, 6 and 7 ), the product yield could be successfully predicted by appropriate choice of pyrolysis conditions.

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Thermal degradation of polystyrene (50 g) was carried out under an atmospheric pressure and at 240-385°C in an isothermal batch reactor.
The rates of the degradation of polystyr ene were determind by the change distribution of molecular weight measured by GPC and of the amount of volatile products. The degradation was treated as a consecutive first-order reaction such as
Relations between rate constants for the com ponents of the degradation products and time are k_a= ln c/θ, k_c= ln(1-c)/θ where A, B and C are polystyrene compounds, trimer like compounds and volatile products, respectively. The rate constants are shown below:
k_a, =1.7 2 e xp (37) X exp (-45.3 x 10³/RT ) (1/hr) and k_c=1.19 exp (39) X exp (-50 X 10³/R T) (1/hr) The ratio k_a to k_ca is k_a/k_c=0.19exp(2000/T)

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In the process of interphase mass transfer, the Marangoni instability, induced by surface tension gradient, has been known to enhance the mass transfer rate. The mass transfer is depend on the enhancement factor, F, of mass transfer coefficient, given by the penetration theory.
For the three or four components system containing one or two solutes transferred, respectively, the enhancement factors were determined by the rate of mass transfer through a quasi- stationary liquid-liquid interface, and the effect of interfacial tension on the instability of the interface was examined.
The variation of F with solute concentration relates to the difference between interfacial tensions, γ_i, which corresponds to the equilibrium concentration at the interface, γ_b, which does to the concentration of the bulk of phase. By the simultaneous counter diffusion of two solutes, the effect of interfacial tension difference, Δγ, on F was determined under the constant values of γ_i. As a result, it was found that (F-1) parallels the 0.6 power of (Δγ/γ_i). Furthermore, by the existence of the fourth component, which decreases the interfacial tension of the system, the more instability of the four components system is promoted than that of the three components system.

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Fluorescence spectra of 4-methyl-7-anilinocoumarin (MAC) and 4-methyl-7-diethylaminocoumarin (MDC) were measured in aqueous solutions of anionic surfactants. CMC was determined from solubilization curves of fluorescent probes in surfactant micelles. This CMC was lower than the value determined from specific electric conductivity. The polarity of the region where the solubilization of fluorescent probes took place was estimated by the measurements of quantum yield and maximum wave number of the probe in aqueous solutions of surfactants.
MAC formed a complex with sodium dodecylbenzenesulfonate (SDBS) by a strong hydrophobic interaction below CMC. However, MDC did not form a complex with SDBS.

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Phenylfluorone reacts with cobalt in the presence of zephiramine and sodium nitrite to form a blue water-soluble chelate. The absorption maximum was found at 645 nm and its absorbance was constant in the pH region 4.55-5.O. The molar absorptivity is 4.8 x 10⁴ at 645 nm and the sensitivity is 0.0012 Co μg/cm² for log (I₀/I) (absorbance) = 0.001. This complex formation was applied to the determination of a microamount of cobalt. The calibration curve prepared at 645 nm was linear for the cobalt concentration up to 2.0 μg/ml.
The composition ratio of cobalt to phenylfluorone in the complex was estimated to be 1 to 2 in the presence of both zephiramine and sodium nitrite.

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By the reductive cleavage of N-N bond in N, N'-dialkylhydrazobenzenes N-alkylanilines is produced during gas chromatographic analysis (injection temp.: 300°C). The thermolysis temperatures of the above compounds, determined by differential thermal analysis, are lower as far as, about 70-80°C than those of the corresponding N, N'-diacylhydrazobenzenes and upon reduction of which with lithium aluminium hydride N, N'-dialkyl compounds are produced. The hydrogen source for the reductive thermolysis arises from water. The above two reaction is provide a convenient means for analyzing ring-substituted N-acyl- and N, N'-diacylhydrazobenzenes.

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“Resin Spot Test” method has been applied to the detection of a minute amount of chromium (VI). A few particl es of the anion-exchange resin (Dowex 1-X1 [SO₄]) were mixed with a drop of the sample solution on a white spot plate. After chromium (VI) was concentrated on the resin particles, the solution around the particles was removed by a piece of filter paper. On addition of a drop of O.2 N H₂SO₄ and a drop of 0.02% 1, 5-diphenylcarbonohydrazide, red purple color appears on the resin particles. The limit of identification is 0.0003 μg, and the dilution limit is 1: 10⁸. Sn (II), Fe (II), Mo (VI) and W(VI) ions interfere with this test.

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The reaction of ferrocene with carbon dioxide in the presence of aluminum trichloride was investigated. It was found that the reaction was available as a simple and convenient meth o d for the preparation of ferrocene. carboxylic acid. In contrast to the reaction between alk y lben zene and carbon dioxide which requires relatively high reaction teniperatures and p r e ssures, the present reaction proceeds smoothly under mild conditions (e. g., 1atm, 50°C) to give ferrocenecarboxylic acid in good yields. From the results of the experiments, ferrocenec ar, boxylic acid seems to be formed via a complex of the type (C₅H₅)₂Fe·(AlCl₃)₂·CO₂.

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The polymerization of methyl methacrylate (MMA) initiated by organozinc compounds (R₂Zn; R=C₂H₅, C₆₂H₅CH₂, or C₅H₂) was carried out in dipolar aprotic solvent such as hexamethylphosphoramide (HMPA) or dimethyl sulfoxide (DMSO). The polymerization initiated by (C₆₂H₅CH₂)₂Zn or (C₅H₂)₂Zn proceeds alone in the presence of large amounts of HMPA, while the polymerization initiated by (C₅H₂)₂Zn does not occur under similar condition. The results obtained from the copolymerization of MMA with styrene initiated by (C₅H₂)₂Zn indicated that the polymerization of MMA initiated by the organozinc compounds proceeds in terms of an anionic mechanism. It was concluded that the coordination of HMPA or DMSO to the zinc atom in R₂Zn increases its ionic character of the zinc-carbon bond and induces the polymerization of MMA. The effects of the structure of R₂Zn and the solvents on the reactivity of R₂Zn were discussed.

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