A method termed the"modulated diffusion flame method"is proposed to measure the rate constants of reactions in the gas phase under a reduced pressure. The method is essentially a combination of the conventional diffusion flame with the phase shift technique.
A reactive species is supplied periodically to the surface of a small cube (radius, r0) from the inside. The species diffuses (diffusion constant, D) outwards from the surface while decaying by a first-order reaction (rate constant, k). The concentration of the species should obey the following equation:
dcldt=(D1r2)[010r(r20c10r)]c
The boundary condition at the surface is
(47rro2)(0clor), ro=q, sin ml--Q2
From these equations, the phase lag of the concentration of the species at r from the supply function is derived.
The applicability of the present method was demonstrated for atomic oxgen reactions with olefins by use of a simple reaction apparatus. The phase lags observed were found to be consistent with those calculated by using available data for relevant rate and diffusion constants.

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A technique of LEED-AES with work function measurment has been applied to the study of interaction of Fe (100) clean surface with H₂0, H₂S and H₂Se. These adsorbed molecules were observed to form a disordered structure at room temperature. The surface concentration of the adsorbed molecules was estimated by LEED spot intensity and Auger peak height. The initial sticking probabilities of H₂0, H₂S and H₂Se to the Fe(100) surface at room temperature were 0.1, 0.2 and 0.6, respectively and rate of chemisorption decreased in accordance with (0/0m). The work function measurment showed that the distance between the surface and the sulfur atoms of the adsorbed H₂S molecules was shorter than the distance between the surface and the hydrogen atoms at room temperature. Desorption of H₂S molecules was stimulated by 600 eV electron beam.
When the surface with disordered structure was heated under ultrahigh vacuum condition, it was changed to a surface with c(2 x 2) structure. The (1/2 1/2) LEED spot intensity and the sulfur Auger peak height were measured when H₂S molecules were adsorbed on the Fe(100) surface at 600°C. The adsorption of H₂S on Fe (100) surface was found to obey the linear rate law at 600°C and the initial sticking probability was estimated about 0.7 at 600°C. From the analysis of the intensity-energy curve of the (1/2 1/2) LEED spot of the c(2 X 2) structure caused byoxygen, sulfur or selenium, it was concludedthatthis c(2 X 2) structure was reconstructive structure.

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Reaction of the carbon, deposited on nickel catalysts in terms of butane decomposition, with H₂0, CO₂, and Ha was studied by using a pulse technique at 400-475°C.
In the reaction of carbon with H₂0, the amount of CO, produced was independent of the pulse size and pulse number of H₂O and of the amount of carbon deposited on the catalysts, but was proportional to the amount of catalysts. The reaction apparently was of the zero-order, with respect to both reactants. The observed activation energy was 17 kcal/mol.
In the reaction of carbon with CO₂, the activation energy was 22 kcal/mol. Significant difference was not observed between the reactivity of carbon toward H₂O and that toward CO₂.:
The reaction of carbon with H₂O or, with CO, was accelerated by the addition of K2CO₂ or Mg0 to the catalysts, but that with H₂ was decelerated.

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Oxidation of hydrogen sulfide over various poly (metal phthalocyanine) catalysts (Poly-M-Pc) was studied by a continuous flow system at atmospheric pressure. The percentage of the conversion of hydrogen sulfide depended on the kind of central metals. The catalytic activity was found to decrease in the order, Fe>Co>Cu>Mn, whereas the selectivity of the catalysts to sulfur were almost the same irrespective of central metals. Introduction of two kinds of metal ions to the enlarged conjugated system of the catalyst gave little observable effect on the conversion and the selectivity. The order of the reaction over Poly-Fe-Pc catalyst was found to be 0.4 with respect to hydrogen sulfide, and zero with respect to oxygen. The observed activation energy of the oxidation was 8.4 kcal/mol in the temperature range of 160-190°C.

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For oxidative coupling of diphenylmethanimine (Im) in excess pyridine, copper (I) bromide and copper 10 halide methoxide were found to be effective catalysts. This showed that the coupling was not specific for copper (I) chloride. The order of the catalyst activity was as follows: Cu (0Cl18)Cl>CuCl>Cu(OCHB)Br>CuBr. Copper (IC) chloride hydroxide Cu (OH) Cl 6 and copper chloride methoxide Cu (OCH9)Cl 7 gave quite analogous spectra in far- infrared region. The former [ 6] did not form complexes with pyridine and diphenylmethanimine, and was inactive, whereas the latter [ 7 ] was highly active. The active catalyst (7) acted on pyridine and the imine at room temperature in such a way that pyCu (OCHE) Cl C, 83 and ImCu(OCH8)Cl [9] were formed, respectively. Complex(9) gave azine in the presence of oxygen. Therefore, E 7 might catalyze the oxidation of imine in the form of C in pyridine, and azine should be formed through 9 by the ligand exchange with imine. Complex 8 was shown to be of a chlorine-bridged, binuclear structure at the cocentration of the reaction, mononuclear py, Cu (OCHE) Cl in infinite dilution and of a polymeric form of binuclear unit in crystalline solid. The strucure of related copper-complexes, CuX L, CuX2.14, CuX2.2 L, Cu (OR)X and LCu (OR)X (L=py, Im; X=Cl, Br; R CH.) in solid and the structural unit in solution were also discussed on the basis of far-infrared spectra, magnetic moments, and molecular weights.

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Significant amounts of methoxy compounds were obtained by co-pyrolysis of 3, 4-dichloro-1- butene and methanol on activated alumina, together with dehydrochlorinated and isomerized compounds. These methoxy compounds were identified by means of gas chromatography, infrared, and nuclear magnetic resonance spectrography.
The methoxy derivatives of 1, 4-dichloro-2-butene (1, 4-DCB-2) were similarly obtained by the reaction of 1, 4-DCB-2 with methanolic sodium hydroxide at 30°C. Other products obtained were 3, 4-dimethoxy-1-butene, 3-chloro-4-methoxy-1-butene, and 3-methoxy-4-chloro-1- butene.
It was suggested that the methoxy compounds f were formed in terms of SN 2 mechanism on solid basic sites and in terms of SN 1 mechanism, a carbonium ion intermediate, on solid acidic sites of activated alumina.

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Toyama Technical College; Hongo, Toyama-shi 930 Japan The co-pyrolysis of dichlorobutenes (3, 4-dichloro-l-butene and trans. -1, 4-dichloro-2-butene) and methanol on activated alumina was carried out to find the optimum conditions necessary for the formation of methoxy compouds and to elucidate the reaction mechanisms.
The reaction was likely to take place in terms of SN 2 and E 2 mechanisms on basic sites, and in terms of Si, 1 and E 1 mechanisms on acidic sites of activated alumina. The probable reaction scheme is given on the basis of the experimental results.
Other results obtained are as follows:
(1) The methoxy compounds are formed in higher yield with increasing molar ratio of methanol to dichlorobutene than with constant one.
(2) The optimum reaction temperature is 190-200°C.
(3) The time factor (W/F) has a minor effect on the yield of the methoxy compounds, because the thermal decomposition of the products occurs on the surface of activated alumina.

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The basicity of ZnO-TiO₂ binary system was studied by using the dehydrogenation of 2- propanol as a test reaction. The addition of ZnO to TiO₂ increased the basicity and the catalytic activity. The formation of ZnTiO₃ in the ilmenite form was observed with the aid of X-ray diffraction analysis. The diffraction intensity of the ilmenite form increased linearly with the increasing content of ZnO up to 25 mol%. The crystalline ZnO was not detectable in these samples. In addition, the specific surface area was almost independent of the amount of ZnO added (Fig.2). These results suggested that ZnO was highly dispersed forming ZnTiO₃. A linear relationship between the dehydrogenation activity and the amount of basic sites at H0 z + 9.5 was obtained (Fig.6). However, it was shown by poisoning test with pyridine and piperidine (Fig.7 and 8) that the acidic sites also take part in the dehydrogenation of 2-propanol. The infrared absorption spectra of surface isopropoxide species was studied and compared with those for alkaline earth metal oxides, to elucidate the roles of acidic sites (Table 2 and Fig.9).

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The isomerization and hydrogenation of 1-butene were studied over MoO₃A1205 catalysts reduced with hydrogen to elucidate the relation between the activity and the acidic property of the catalysts. The catalytic activities for the isomerization and the hydrogenation were remarkably increased by pretreatment with hydrogen above 400°C (Fig.2). The activities were found to be poisoned reversibly with water and irreversibly with triethylamine, but not with carbon dioxide (Fig.4). The increasing catalytic activity for the hydrogenation of butene isomers was in the order cis-2-butene<1-butene<trans-2-butene, and the activity for the iso-merization was almost in the same order. It is suggested that the active sites serve as electron acceptors and the sites for the isomerization are different from those for the hydrogenation. The dehydration and dehydrogenation of 2-propanol were also studied over MoOs-A1208 cata-lysts pretreated with hydrogen or hydrogen sulfide (Table 3) and the catalytic activity was discussed in connection with the surface structure of, the catalysts.

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Oxidation-reduction cycle treatments of powdery iron and copper at 350-650°C were performed for investigating the relationships. between oxide whisker growth on the metal surface, sintering of the metallic powders and the catalytic activity on the metals. The oxidation and reduction processes of the powders were studied by micro-thermogravimetric analysis, and changes of the surface were measured by means of electron microscopes, IT, adsorption at low temperature, and catalytic CO-oxidation rate in a flow method.
O^2- uptake in the oxidation process at the temperature where the whiskers grew decreased with the frequency of oxidation-reduction cycle (n) for both iron and copper powders. Irrespective of this change, there were some O^2- uptakes (elwfn) with a time-independent and high absorption rate in the initial stage of each oxidation process. The linear relationship between zlivin in the nth cycle and the BET surface area of the powder in the (n)th cycle, (S(7, _1)), was observed, i. e., Awryz.=a S (, ). The correlation between the degree of the sintering progress at the nth treatments (R, =4(4w)14n) and the amount of whisker growth (M), Rsn, =7"Ma, (8<l) was found. The n-dependence of R.7, was also shown to be given by the relation, n. CO-oxidation activity decreased with the progress of the sintering as n increased.
On the basis of these results, it is concluded that the sintering is enhanced and deterioration of the catalytic activity proceeds under the condition that the whiskers grow more thick.

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Anodic behaviour of zinc electrode has been studied in concentrated alkaline solutions by using a rotating ring-disk method.
As the rotational speed of the zinc anode was increased, the collection efficiency for zinc deposition at the ring electrode had tendency to decrease in various concentrations of the alkaline solutions.
Those observations lead to an interpretation that a species in the anodic reaction produces an inactive intermediate by charge transfer process and that this intermediate transforms to electrodbemically active products by chemical dissolution in the bulk.
From the observation of the ring current during a linear potential scan, it is suggested that a soluble species, which is reduced at the ring electrode, is passivated when its concentration reaches a critical value on the disk electrode. This species is suggested to be Zn(OH)42- by means of laser Raman analysis.
Those results are consistent with the anodic formation of Zn (OH), in alkaline solutions by a dissolution-precipitation mechanism. It is considered that the passive film is grown by a diffusion control reaction in the vicinity of the metal surface and/or by a direct oxidation at the same metal in the potential region less noble than +0.6 V (against Hg/I-IgO).

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For thermochemical production of hydrogen from water, the thermal catalytic decomposition of sulfuric acid has been investigated. This is one of common oxygen-producing reactions for many sulfur families of water splitting cycle.
Experiments were conducted with 98% (in wt. ) sulfuric acid and in the temperature region 750, -900°C. Complete decomposition of sulfuric acid into sulfur trioxide and water was observed in this temperature region, but a catalyst was found to be required for the rapid reduction of sulfur trioxide to sulfur dioxide and oxgen. Preliminary experiments revealed that some substances such as Pt, Pd, CuO, Fe2O₃ and V206 were effective as the catalysts. Among them Pt and Pd showed the good catalytic activity which may be brought by chemisorption and desorption. The activity of the metal oxide catalysts could also be interpreted by redox reactions on semiconductive surfaces. In this mechanism the formation of sulfate or oxide sulfate loweres the catalytic activity.
Three catalysts were prepared by supporting Pt, CuO and Fe20, gn such a carrier as alumina. And the kinetics of these catalysts was investigated. A Pt-A1, O^2-(5 wt%) catalyst gave a conversion close to equilibrium conversion of sulfur trioxide to sulfur dioxide and oxygen at 800-, 900°C and the space velocity of 5000-10000 hr-1. The activation energy of the reaction was 16.9 kcal/mol. °K, and the value of frequency factor was 4.2 x 107 hr-'. CuO-A12O^2- (5 wt%) and Fe209-A12O^2- (5 wt/) catalysts also showed good catalytic activity comparable to that of Pt.

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We found that electrodes burnt in an Argon gasstream had a long life in an amalgam cell and that the burnt layer was identified as the metals of the platinum group by X-ray diffrac. tion.
The electrodes burnt in the closed atmosphere had the same life as those burnt in the Argot gasstream. This burnt layer was the mixture of the metals and their oxides. Therefore, ii seems that the burnt metal of the platinum group is useful as the metallic anode for th( electrolysis of alkali chlorides.
Some performances of the metallic anode in an amalgam cell were summarized as follows: 1) The cellvoltage was 3.95 to 4.25 V at 100 A/cm².2) The current efficiency was 96%.3) The H, content in Cl, gas was undetected.

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Cr2O₃ single crystals were grown from the VO, fluxed melt having 10 mol% CrOs and 90 mol% V205 by slow cooling method. Starting mixture was kept in the temperature from 1100 to 1400°C and cooled with the rate of 3.3 to 30°C/hr. Temperature difference of the upper and lower parts of the melt was about 30°C.
Cr, O, single crystals larger than about 1 mm in size were grown near the surface of the melt with their c-plane parallel to the melt surface. They are mostly tabular bounded by c (0001) and n(2243) or r (1011) faces, and their maximum size. was 10.0 X 4.0 X 0.25 mm. Several of these single crystals were twins with twin plane of m(1010).
Small amounts of needle and ribbon crystals were also formed when cooling rate was fast and slow, respectively.
Good crystallinities of the prepared Cr209 single crystals were shown by the analysis of Xray diffraction patterns. The amounts of vanadium, contained in the Cr2O₃ crystals as an impurity, were less than about 0.3 wt%.

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Three geometrical isomers of the [Co(L-asp) (L-orn)] complex and three geometrical isomers of the [Co(D-asp) (L-orn)] complex have been prepared (asp =aspartate ion and orn=ornithinate ion), and their configurations are determined from the visible absorption and proton magnetic resonance spectra. The absorption spectrum of trans 05 trans N5 isomer of No(D-asp) (L-orn) is of particular interest since there is a clear shoulder in the second absorption band region which may be due to the splitting of that band. The isomerization of these six isomers was observed in the aqueous solution containing active carbon. After an equilibrium, the isomer ratio was found to be cis 05 cis N5: trans N5 trans IT, fac = 50: 14: 29. The ratio for the isomers containing L--asp could not been obtained because of their low solubilities. The rates of these isomerization were dependent on the pH of the solution, slow at low pH and rapid at high pH. The addition of the organic material decreased the rates of isomerization. Pyridine and anilin showed a more pronounced effect than ethanol, tetrahydrofuran and dimethyl sulfoxide. It is found that the Co(D-asp) (L-orn) and Co(L-asp) (D-orn) complexes are formed by the isomerization of the mixture of the ECo(D-asp) (D-orn) and Co(L-asp) (L-orn) complexes in the aqueous solution containing active carbon. This fact shows that the isomerization occurs via intermolecular as well as intramolecular mechanisms.

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It has been revealed from spectroscopic investigation that when nickel (II) ion in aqueous solution is mixed with an equimolar amount of crystalline 1, 10-phenanthroline(phen), a greater part of nickel forms [Ni(phen), ]2+ complex, leaving a part of ENi(H₂O)O^2-+ uncomplexed. Then, the complex slowly changes to an equilibrium complexes, the most abundant species being ElsTi(phen) (H₂O)42 This phenomenon is not observed for hydrophilic ligands such as ethylenediamine. The amount of [111(phen). ]2+ formed immediately after the mixing decreases with increasing concentration of ethanol when an ethanol-water system is used as solvent. Manganese(11), cobalt( if ) and copper ( ) complexes, which are more labile than the corresponding nickel (II) complex, do not form 1: 3 complexes of metal and 1, 10-phenanthroline at the moment of mixing of these ions in aqueous solution with 1, 10-phenanthroline crystals by the mole ratio of 1: 1. The formation of 11(phen)92+ at the moment of mixing of nickel (11) ion and 1, 10-phenan. throline crystals may be due to the non-uniform distribution of 1, 10-phenanthroline in the reaction system, very quick formation of the 1: 3 complex owing to the hydrophobic property of 1, 10-phenanthroline and rather slow aquation of the complex.
The, i2+-catalyzed decarboxylation of oxaloacetic acid is accelerated by the 'addition of one mole of_1, 10-phenanthroline crystals per mole of nickel (II) ion, and the rate constant increases with lapse of time after the addition. The increase of the rate constant probably results from the gradual change of [Ni(phen), ]2+, formed immediately after the addition of 1, 10-phenanthroline crystals, to the more catalytic species, [1Ti(phen) (H₂0), ]", through the aquation.

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Thirty-five pyrimidine compounds have been studied as reagents for the spectrophotometric determination of cobalt (11).2-Amino-5-nitroso-1, 4, 5, , 6-tetrahydropyrimidine-4, 6-dione (ANP) reacts with cobalt (11) to form a water-soluble yellow complex. Cobalt (111)-ANP complex has an absorption maximum at 375 nm against a reagent blank and shows a constant absorbance over the pH range from 4.8 to 6.0. Beer's law holds over the range from 0 to 2 iug/m/ of cobalt at 375 nm; the molar absorptivity of the complex and the sensitivity for log (I01) = 0.001 are 5.30 x 10^2- / mol-1 and 1.11 x 10-3 mg cm^-2, respectively. The coefficient of variation was 0.40% for 1 juglml of cobalt (III) Copper ( II) and iron (Ill) interfered with the determination, but could be masked by the addition of 6 N hydrochloric acid. The ratio of cobalt On to ANP in this complex was found to be 1: 3 by the continuous variation method.

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Linear simultaneous equations based on exact material- and charge-balance relationships were proposed in order to determine the composition of mixtures of weak acids or cations by using the results obtained by a potentiometric titration.
The procedure is as follows; Titration curves for the reference solutions of components of the mixture (known concentrations) and the sample mixture were obtained at a constant ionic strength by using an ion-selective electrode. Volumes of titrant required to reach a constant ionic concentration (i. e., constant electrode potential) were read off respectively on titration curves of the mixture and its components. Then, the composition of the mixture could be determined by solving simultaneous equations involving the measured ionic concentrations and the volumes of titrant as variables (see Eqs. ( 4 ) and (11)).
The present method has an advantage that equilibrium constants are not necessary for the calculation of the concentration.

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Thiosulfate was titrated with silver nitrate utilizing the formation of thiosulfatoargentate. The end point was detected with silver ion selective electrode and SCE. It was found that thiosulfate ion reacted with silver ion to form thiosulfatoarge. ntate ion quantitatively at a temperature below 20°C in the presence of calcium nitrate above 0.01 moll/. The effects of some concomitant compounds on the titration were also investigated. The recommended procedure is as follows.
( 1 ) Standardization of sodium thiosulfate solution Place 10 ml of 0.005 moll/ sodium thiosulfate in a titration cell. Add 4 ml of 0.5 mol/l calcium nitrate and make upto about 100 ml with oxygen free water. Titrate this solution with 0.1 moll, silver nitrate at room temperature below 20°C. The relative error and the coefficient of variation were respectively 0.2% when the titration was carried out in 6 minutes.
(2) Determination of sodium thiosulfate in the presence of sodium sulfite Titrate 100 ml of 0.00005 mol/l thiosulfate solution containing large amounts of sulfite with 0.01 moll/ silver nitrate at the temperature of about 10°C. Before titration, add 4 ml of 0.5 molt calcium nitrate and adjust the pH of the solution to 1.5-2.0 with dilute sulfuric acid.
A small amount of sodium thiosulfate (e. g.100 ppm) in sodium sulfite was determined with the relative error of +3.3% and the coefficient of variation of 0.5% when the titration was carried out in 25 minutes. This titration method is rapid, simple, precise and especially suitable for the determination of thiosulfate in the presence of sulfite. A conventional silversilver sulfide indicator electrode could be also used.

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The rates of the reaction of (diethylamino)dialkylphosphine with ethylene carbonate have been determined by measuring with IR spectra the decrease in the amount of ethylene carbonate. The rates varies according to the class of the alkyl substituents on the phosphorus atom, i. e., the order of the rate was as follows:
Secondary alkyl>Primary alkyl>Methyl
Good correlations with Taft equation were found in each class of the alkyl substituents, and the p was found to be positive. The results are consistent with a mechanism involving a four-centered transition state where the phosphorus atom acts as an electrophile site and accepts the electron pair from the ester-oxygen atom of ethylene carbonate. In addition, the electrophilicity. of the phosphorus atom is affected considerably by the hyperconjugation effect of the substituents on the phosphorus atom.

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The reaction of isooctane (2, 2, 4-trimethylpentane) with carbon monoxide was studied in the presence of HF-SbF, super acid system with various HF/SbF5 molar ratio (2, 20) at 0°C under atmospheric pressure. The reaction products were 2, 2, 5-trimethyl-3-hexanone, 2, 2, 5-trimethy1-4-hexen-3-one [ 2 ], a, 8-unsaturated cyclic ethers (Cl314240) 3, and 2, 2-dimethylpropionic acid.
Although the reaction seems to be initiated by the protolysis of isooctane giving 1, 1, 3, 3- tetramethylbutyl cation which in turn cleaves into t-butyl cation and isobutylene, the main reaction path for the formation of 1, 1, 3, 3-tetramethylbutyl cation can be considered to proceed via the intermolecular hydride transfer between isooctane and t-butyl cation. t-Butyl cation thus formed reacts with carbon monoxide to give pivaloyl cation. The formation of Cl J, [2], ( 3 ), and 2, 2-dimethylpropionic acid can be explained in terms of the reaction paths, shown in the equations ( 5 ), ( 8 ), ( 9 ), (10), (11) and (12).

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The alkaline hydrolyses of bis(nitromethyl)benzenes with aqueous sodium hydroxide were studied. The hydrolysis of the o-isomer at elevated temperatures proceeded smoothly to afford disodium phthalate in a good yield. However, m- and p-isomers as well as phenylnitromethan were not hydrolyzed. At room temperaure, the treatment of the o-isomer with aqueous sodium hydroxide produced the sodium salt of phthalimide and N-hydroxyphthalimide in addition to the sodium salt of phthalic acid. N-Hydroxyphthalimide was hydrolyzed more easily than phthalimide in aqueous alkaline media. These results summarized in Tables 2 and 3 suggest that the high reactivity of the o-isomer arises from the interaction of the two adjacent nitromethyl groups on the benzene ring and the main intermediate is N-hydroxyphthalimide.

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The effects of added nitrile and sodium pyrophosphate on the autoxidation of cyclohexane and the decomposition of cyclohexyl hydroperoxide (CHPO) have been studied.
The selectivity for CHPO in the autoxidation of cyclohexane was 8.27 mol% higher in the presence of sodium pyrophosphate alone or together with a nitrile than in the absence of these addenda. The addition of sodium pyrophosphate and/or acetonitrile slowed down the decomposition rates of CHPO and 1-tetralyl hydroperoxide (THPO) in cyclohexane and tetralin, respeceively.. The added sodium pyrophosphate appears to mask the aluminium ions which accelerate the decomposition of CHPO and THPO. CHPO and, THPO can be stabilized by associating with nitriles and sodium pyrophosphate.

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The influence of sodium halides on the kinetics of the dyeing of formalized ( I ) and acidtreated formalized (II) PVA fibers with direct dye has been studied at 80°C and 90°C. Each dyeing was made in an infinite bath with 3x10-5 moll/ of Congo Red and with 0.1 mol/l of sodium halide. The apparent diffusion coefficient (D) (Table 2) and the apparent rate constant of dyeing (K) (Table 3) decreased with an increase in degree of formalization of the fiber. These values decreased gradually in the order NaF<NaCl<NaBr<NaI, but the equilibrium sorption of dye (C.. ) (Table 1) increased in the order NaF<Nael<NaBr<NaI. The D, K, and Cm values for II were markedly larger than those of I. The kinetics of the dyeing of I and IT with direct dye appear to be appreciably affected by the inorganic electrolytes (sodium halide) and by the cross-linking formed in the formalization reaction of the polymer.

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In an aqueous solution, the polymerization of vinyl monomers initiated with sodium poly (2-propene-1-sulfonate) (PPS-Na) was carried out. The polymerizations of methyl methacrylate(MMA) and acrylonitrile were promoted by the addition of PPS-Na but those of styrene and methacrylonitrile were not. The polymerization proceeded through the radical mechanism and the rate obeyed Michaelis-Menten equation. The relationship between the conversion of MMA and pH of the aqueous solution or the polymerization temperature was of downward bell type. Thus the polymerization system could be regarded as an enzymatic model.

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This paper deals with the novel chemical reaction of carboxymethyldextran (CMD) with gelatin, comprised of various proteins having different isoelectric points, bringing about complex, and the properties of the complex produced.
The resolubilization of a precipitate occurred when an excess of CMD solution was added dropwise to a gelatin solution. In addition, the coagulation of a precipitate was observed at pH 5 but not at pH 8 when a gelatin solution was added to a CMD solution. It seemed that the degree of dissociation, the conformation of CMD, and the net charge of gelatin changed with a concentration of hydrogen ion.
With reference to the addition of guanidine hydrochloride or urea to the reaction system, IR spectra, elemental analyses, the resolubilization of a precipitate, and the fractionation of gelatin, developed by Dr. Sevensson et al., suggested that the binding of gelatin to CMD was attributed to the ionic bond between COO- and amino groups, the hydrogen bond between OH or CO group in CMD and CO or amino group in gelatin, and the distribution of cation and anion charges in gelatin.

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The effect of natural zeolite on the thermal decomposition of polypropylene has been examined in the range of 400 to 550°C by analyzing the decomposition products with gas chromatography and infrared spectroscopy.
The presence of zeolite accelerated the decomposition of the polymer and remarkably affected the decomposition products. While main products without zeolite were pentane and alkenes such as propylene, 2-methy1-pentene, and 2, 4-dimethy1-1-heptene. Alkanes such as propane, isobutane and isopentane were mainly produced in the presence of zeolite.
The results suggest that the thermal decomposition of the polymer proceeds via radical mechanism without zeolite and mainly through carbonium ion formation in the presence of zeolite.

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Pyrolysis, of atactic. polypropylene (APP).1, means of fluidized bed was studied. APP was melted and then fed continuously into a bed of 110 mm I. D. where sand particles were fluidi zed by air. Temperature of the bed was sustained enough by partial oxidation of APP in the range from 400°C to 640°C, and APP was decomposed to gas and oil.
The yields of gas and oil were 7-36 wt% and above 50 wt%, respecti'vely. Physical proper ties such as viscosity, heat of combustion, boiling temperature and molecular weight of pro duced oil were studied with relation to operation conditions of fluidized beds, and it was found that oil' can be reutilized as a good substitute for fuel oil.

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The effects of pore size distribution, pH, and electrolytes on adsorption of sodium dodecylbenzenesulfonate (SDBS) on activated carbons with different pore size distributions were investigated in aqueous solutions with various electrolytes.
The adsorption isotherms of SDBS on activated carbons were of Langmuir type. The apparent occupied area per molecule (Sm) of SDBS was small for the activated cardon with many large pores (LP carbon) and was large for the activated carbon with many small pores (SP carbon). The adsorption equilibrium constant (a) was small for LP carbon and was large for SP carbon. The adsorption isotherm in low equilibrium concentration represents the adsorption mainly for small pores and the isotherm in high concentration represents the adsorption for large pores. These results could be explained by the concept that adsorption by dispersion force for small pores was larger than that for large pores.
The amount of adsorption remarkably increased in the pH below 4 was probably caused by carbon surface oxides or the adsorption of dodecylbenzenesulfonic acid.
The effect of coexisting cation on the adsorption was larger than that in coexisting anion. In the cases of electrolytes with same anion, the removal efficiency of SDBS by activated carbon increased with increasing charge of cation, or with increasing ionic radius. SDBS formed a complex with a cationic surfactant, and the removal efficiency significantly increased because of low solubility of the complex.

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Size distributions for and concentration ratios between silicon and aluminium in atmospheric particulates were investigated in order to make clear the characteristic of naturally born aerosols in the air. Fractions of atmospheric particulates collected with an Andersen cascade impactor were ashed and solubilized by alkaline fusion.
Silicon was determined photometrically by a Molybdenum Blue method, aluminium by a Chromazurol S-hexadecyltrimethylammonium chloride method. About 90% of the atmospheric silicon and aluminium were concentrated in the particulates larger than 2, u in diameter. The size distribution characteristic for silicon was in good agreement with that for aluminium, e., the mass median diameter (M. M. D. ) was about 5, u and the size distribution curve foliwed approximately log-normal distribution in which the modal diameter was 3-5, u.
The concentration ratio (Si/A1) gave an arithmetic mean of 2.6, and the coefficient of variation of 12.1%. These size distributions and the Si/Al ratio were little affected by yellow sand wind. It is supposed that atmospheric silicon and aluminium come from the same common windblown soil, and keep its original mineral composition.

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A tribophysical process for producing extremely small particles of platinum uniformly dispersed on alumina is described in this Note. The platinum-alumina catalyst has been tested with a slow combustion of gaseous hydrocarbons over it. The test showed that this catalyst performed well and exhibited a long life span when compared with the platinum-alumina catalyst manufactured by ordinary chemical means. Platinum particles in this catalyst differed from platinum bulk in structure.

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The solubility of iron (III) fluoride trihydrate (FeF3.3 H₂0) in mixtures of nitric acid and hydrogen fluoride at 20°C can be expressed lay the following formula:
where mFo is the solubility of FeFe 3 H₂O, msF and mHN are the respective concentrations of HF and HNO₃ (mol/1000' g H₂0), and a is the degree of dissociation of HF in water at 20°C. The equation indicates that the solubility of FeFe 3 H₂O decreases with increasing concentration of HF and/or HMO. The equation was found applicable in the concentration range mFe. <0.4 mol/1000 g H₂O.

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