The. effects of guanidinium ion and its salts (chloride, bromide, thiocyanate, nitrate, acetate, sulfate and carbonate) on the structure of water were studied by the measurements of the mean activity coefficient, conductivity and density at 25° C. The values of mean activity coefficients, of all guanidinium salts were smaller than those of alkali metal salts with the same counter ion except for the case of cesium chloride at low concentration. These low values of r were interpreted in terms of structure breaking actions of these salts. As shown in Table 3, the values of r for 1: 1 valence type lied in the order OAc- >Cl-> Br^- > SCN >NO, - and for 1: 2 type C082- >SO₄2-, which were the reverse orders of structure breaking abilities of these ions. These orders of r can be well interpreted by regarding the guanidinium ion as a structure breaker and using the Desnoyers' model of ion-ion interaction in which the overlapping effect of hydrated cosphere was taken into account.
Partial molar volumes of guanidinium ion at infinite dilution were 44 ml/mol and 49 mi/niol for 1: 1 and 1: 2 type respekively. These values are larger than the molar volume of guanidinium ion in crystal, 40 ml/mol.
As shown in Fig.2, the equivalent conductance of guanidinium chloride obeys the OnsagerFuoss' equation at low concentration, and the values of 129.7 and 53.3 were obtained for the equivalent conductances of guanidinium chloride and guanidinium ion at infinite dilution respectively. Application of, modified Stokes' law gave a value of 75.1 ml/mol for the molax volume of the hydrated guanidinium ion. From these data it was found that guanidiniuni ion was hydrated with about 2 molecules of water. This hydration number is considerablly small as compared to the results of Li+ and Na + which have the hydration numbers of 7 and respectively. From the above results, guanidinium ion was concluded to be a structure breaking ion.

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Ultrasonic absorption spectra in sodium chloride dioxane-water solutions were measured by the ulrasonic pulse method. from 10 to 110 MHz, and ultrasonic velocities were measured by interference of pulse wave and continuous wave at 5 MHz.
Sodium chloride dissociates completely in aqueous solution, and ultrasonic absorption due to relaxation was not found in the solution. If dioxane added to the solution to reduce the dielectric constant, dissociation equilibrium was held between sodium ion, chloride ion and undissociated sodium chloride, and the ultrasonic absorption due to the relaxtion of the reaction was observed.
The volume change due to dissociation of sodium chloride was calculated from the ultrasonic absorption spectra, and compared with the values estimated from pressure change of dissociation equilibrium of sodium chloride in dioxane-water solutions, and the agreement between them was fairly good.
Therefore, the ultrasonic absorption found in sodium chloride dioxane-water solutions is attributed to the relaxation of dissociation equilibrium of sodium chloride in the solutions.

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Crystals of K2SO₄ containing T12SO₄, which were prepared by, crystallization from the aqueous a solution of various Ti contents, were, fired for, 1 -hr at 450-1000° C in each atmosphere of He H₂, 02 or vacuum. The glow curves of the crystals exposed to Sr source were obtained by using a therrnoiuminescence reader.
The-thermoluminescence intensity reached a maximum at Ti Concentration of 1 mol%, and the intensity decreased with the rise of firing temperature in. He. It was suggested that the luminescence center was destroyed by the formation of micropores and cracks on the surface layer of crystal during firing (Fig.5).13y firing in 02, the thermoluminescence intensity increased owing to the formation of electron trap by the diffused oxygen. By firing in H₂, the obtained crystal blackened, Y and the thermoluminescence disappeared. In the case of the mixed crystal of 1C_2CSO₄ and Na₂SO₄ (30 mol%), the thermolurninescence intensity was very strong, and this fact was explained on the basic of the principle of -compensation of volume.

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Oxidation of propylene and isobutylene over mercury (II) chloride-active charcoal catalyst was studied in the presence of excess oxygen and steam at atmospheric pressure. As a main product, propylene gives acrylaldehyde, and isobutylene gives methacrylaldehyde. The yield of unsaturated carbonyl compounds increased in proportion to the concentration of oxygen. The selectivity to acrylaldehyde was 75% under oxygen/olefin =1 (mole ratio) and methacrylaldehyde was obtained 70% selectivity in isobutylene oxidation under the same reaction conditions. Addition of such metal chloride as CuCl2, FeCl3 and BaCl2, stabilized the catalytic activity for acrylaldehyde formation from propylene.
The rate of methacrylaldehyde formation decreased with the amount of CuCl2, FeCl3, and BaCl2 added, while these catalytic activities were nearly constant at 140° C.

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The reaction of NO with CO over various metals or metal oxides supported on alumina was carried out by means of a conventional flow method. The reaction mechanisms over Fe2O^3- Al202 and CuO-Al203 were especially studied here from the kinetic point of view. The oxidation state of the catalyst, as measured by 02 titration, changed with gaseous composition of NO and CO. It was well correlated with the rate of reaction as shown in Figs.1 and 3. The rate of reaction and also oxidation state of the catalyst were expressed as functions of gaseous pressures of NO and CO as given by eq. (10) and ( 9 ), respectively. The equations were verified in Figs.2 and 6 and kinetic parameters were calculated from them. These values existed in rational region when redox properties of the catalyst were taken into consideration. Then, the redox mechanism which was confirmed in our previous papers2(7) for the reaction of NO with H₂ over Fe208-Al203 was also valid for this reaction.
Judging from the values of rate constants, the main resistance in the reaction over Cu0- Al20, catalyst was oxidation step. On the other hand, all the steps contributed in a similar extent over Fe202-Al203 catalyst.

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In the activated-carbon processes for flue gas desulfurization, SO₂ is catalytically oxidized to 1-12SO₄ on activated carbon. In the previous paper, it was proposed that this reaction consists of an anodic oxidation of SO₂ and -a cathodic reduction of 02. Such electrochemical mechanism was confirmed in the case of the reaction on Pt in H₂SO₄ solution. In this paper, it was intended to make clear this reaction on carbon from the electrochemical point of view. Carbon powder was suspended in the electrolyte (1 N H₂SO₄) in which SO₂ and/or 02 were dissolved and the current-potential curves were determined by using Pt gauze as a collector electrode, while the rate of catalytic oxidation of SO₂ was measured by an analytical method. Anodic and cathodic polarization curves were obtained reproducibly, which corresponded to electroche- mical oxidation of SO₂ and reduction of 02 on suspended carbon particles, respectively (Fig.2). Reciprocal slope (di/dE), of micropolarization curve around rest potential in the presence of dissolved SO₂ and 02 was proportional to the amount of suspended carbon and the stirring rate. The rate of catalytic reaction of SO₂ and 02 dissolved in FI2SO₄ solution was proportional to (di/dE), for various carbons (Fig.11). This fact was interpreted by the quantitative consideration of charge which transfered between the carbon particles and collector electrode on collision. It was found that carbon which exhibited high- activity to cathodic reduction of 02 was also active to catalytic oxidation of SO₂.

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An improved extraction method with 8-quinolinol has been studied on the determination of lower molecular weight iron (III) ions in aqueous solution in the presence of higher molecular weight iron (111) ions. The extractable iron (III) species were considered to be the monomeric species. The monomeric species (lower molecular weight iron (Ill) ions) were also confirmed by UV spectroscopy and ultrafiltration (Diaflo Membrane UM). The rate of hydrolysis of iron (ff) ions was measured by the improved extraction method. The reaction rate is of the second order, and the Arrhenius plots of the rate constants vs. temperature gave a straight line. The Arrhenius activation energy (4E4), activation freeenergy (tIGI. K) and activation entropy (4S) are 39.5 kcal/mol, 16.4 kcal/mol and 73 e. u. ([Fes]: (1.40.1) x 10-4 mol/l, pH: 3.40 0.05) respectively.

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High temperature gas-flow DTA apparatus working up to 1500° C was used to investigate the reversible reaction among calcium sulfate, aluminum oxide, calcium aluminate, and 'air-S02 mixture, shown in the following equation;
For the forward reaction, the experiments were carried out by using- GaSO₄-77-Al203 and CaSO₄: -ce-Al203 mixtures (1: 1 in mole ratio) in flowing nitrogen (100 m//min) up to 1400° C. For the reverse reaction, the experiments were carried out by -using air-SO₂ gas mixture (1: 1 in mole ratio and the flow rate of 100 m//min) and calcium alurninate samples prepared from -CaSO₄-Al203 mixtures by heating them at 1300° C for 1 hr. Thermal decomposition of pure CaSO₄reaction of CaO with Al203 and that of Ca-0 with air-SO, mixture were also tesied. to compare them. with the reactions in CaSO₄-Al203 sy'ste'rng.
The results are summarized as follows: (1) In the CaSO₄-Al203 system, the decomposition of CaSO₄ (CaSO₄ Ca0 S08, 4H° (1373 K)=89.7 kcal/mol) and the formation of calcium aluminates (for example, CaO + Al203 CaO. Al203, .411° (1373 K)=.5 kcal/mol) occur simul7 taneously. The corresponding endothermic DTA peaks appear at 1140° C and 1190° C for CaSO₄ -n-Al203 and CaSO₄r-Al203 systems, respectively (Fig.1). (2) The decomposition of CaSO₄ is promoted by Al203; the decomposition occurs at lower temperature and the rate is higher when Al203 is present.72-Al203 was found to be more effective than a-Al203 (Fig.1 and 2). (3) CaO formed by the decomposition of CaSO₄ shows higher', reactivity than commercial CaO for the formation of calcium aluminate. Various types of aluminates, CaO. Al203, 12 Ca().7 Al203, 3 CaO.5 Al203, 3 CaO Al20 CaO.6 Al203 and x Ca0. y Al203 are formed and the kind of aluminates formed seemed to depend on the reactivity of CaO and/or Al203, as well as upon the composition of system under the working state. A new unknown aluminate x-CaO Al203 is formed for which x is assumed to be smaller than y (Table 1 and Fig.3 and 5). (4) Calcium aluminates are more reactive than commercial CaO for air-SO₂ mixture and the starting reaction temperature with SO₂ is lower for the aluminates prepared from 7-Al203 than that from ce-Al203 (Fig.4 and 6). (5) Calcium aluminates react with air-SO₂ mixture to produce CaSO₄ and 77-Al208, and the aluminates with values of m/n 1 are active (Fig.5 and 7). (6) The above results were confirmed by -the consecutive DTA experiments carried out in air-SO₂ mixture and in N2 (Fig.6).

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Free sodium hydroxide and sodium chromate was separated from the reaction product of chromite with molten sodium salts by the two-step leaching with methanol and water.
In the first step, the reaction product was leached with methanol. About 90% of free sodium hydroxide was selectively dissolved in methanol under the following optimum conditions; weight ratio of 90% methanol solution to the reaction product: 4.0, leaching temperature: 35° C, leaching time: 1 hr.
In the second step, the leached residue was leached with water. Whole sodium chromate was dissolved in water.
On the basis of experimental results, a process for the production of sodium chromate from chromite was proposed.

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Copper (II) ion reacted with 2, 2'-bipyridine (Bipy) and Chromazurol S (ChS) to form a mixed ligand complex, and it had an absorption maximum at 510 nm in a weakly basic pH medium. The molar ratio of three components in the complex was estimated to be Cu( II ) Bipy: ChS =1: 1: 2 by means of the continuous variation method and by the mole ratio method, and then the logarithmic value of the apparent formation constant of the complex was calculated to be about 19.12. The mixed ligand complex gave a maximum absorbance at 510 nm in the pH range from 10.0 to 10.6. The color development was almost instantaneous, and the absorbance remained constant for many hours. Under the optimum conditions of pH, Bipy and ChS concentrations, a linear relationship was found between the absorbance and copper (II) concentration up to 6. Ox 10-5 mol/l (Beer's law). The molar absorptivity at 510 nm was about 20600 /cm-imol-', corresponding to Sandell's sensitivity index' of 0.003g/cm².

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Anodic stripping voltarnmetry for As (III), Te (W) and Se ( IV) using codeposition with copper and for Ga (III) with Zn(II) has been studied, and the mechanism of the codeposition and the dissolution of As-Cu, Te-Cu, Se-Cu and Ga-Zn systems investigated by electrolysis and chemical analysis is presented. The working electrode used was a rotating platinum electrode.
Current-potential curves for the deposition of these systems (Fig.6) indicated that two elements are codeposited on the cathode at potential between deposition potential of two elements. Simultaneous codeposition was also confirmed by controlled-potential electrolysis. The deposition behavior of As-Cu system differed from those of the other systems as shown in Fig.2; the cathode potential drifted considerably to negative at first when constant current electrolysis was performed. The peak areas of the second peak in the stripping voltammogram showed maximum when constant current electrolysis was carried out at 1 mA/cm² and minimum at 10-133 mA/cm². Although hydrogen was liberated during codeposition remarkable interference was not observed in these systems except As-Cu system. Arsine is generated during electrolysis of As-Cu system when the deposition current is higher than 1.7 mA/cm². The generation of arsine determined by the spectrophotometric method was maximum when the deposition was carried out at the current of 133 mA/cm² (Table 2). This result clearly explains the fact that the current efficiency for the deposition is minimum at 133 mA/cm².
The current-coulomb curves in the stripping step show that only one electrode reaction is taking place at the working electrode. Mole ratios of two elements in the deposit determined by chemical analysis revealed that the second peaks in the stripping voltammograms were resulted from the dissolution of such compounds as Cu3As and Cu2Te3 and Cu2Se3 deposited from sample solutions containing As and Cu, Te and Cu, and Se and Cu, respectively.

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A simple and rapid X-ray fluorescent method was proposed for the determination of trace amounts of manganese and iron in titanium. The sample was dissolved by the successive addition of sulfuric acid, hydrofluoric acid and nitric acid, and 3 g of boric acid was added. The sample solution was diluted to a definite volume with water, and 50 pg of cobalt was added as an internal standard. After the addition of 5 ml of 10% sodium citrate solution to an aliquot (less than 100 pg or 200 pg of each manganese and iron) of this solution, the pH was adjusted to 7-9 with ammonium hydroxide and 5 ml of 10% sodium diethyldithiocarbamate (DDTC) solution was added. The precipitate of DDTC complex was collected on a membrane filter and dried. Then, the ratios of Ka fluorescent intensity for each element to that for cobalt were calculated referring to the calibration curves, which were linear up to 100 pg of manganese and 200, ug of iron. The coefficients of variation for five determinations were O.66% and O.42% for 50 pg of manganese and 100 pg of iron respectively, in the presence of 50 mg of titanium. The analytical results for each element in the titanium by the propsed method were in good agreement with results obtained by other methods.

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The thermal decomposition of MgCl2 H₂0 has been studied by thermogravimetry (TG) and differential thermal analysis (DTA) in the pressure range from one to 30 atm, and by the thermal analytical technique based on electrical conductivity (EC) at atmospheric pressure.
Although the TG curves of the decomposition under one and 3 atm indicated the presence of four step reactions, the TG curves of decomposition above 10 atm showed two step reactions apparently. Six endothermic peaks appeared on the DTA curve at one atm. The temperature of 1 st peak (at 117° C) was unshifted but the other 5 peaks shifted to higher temperature with the increase of pressure. The 1 st peak on the DTG curves corresponded to the 3 rd peak on the DTA curve, and the initial and final positions of EC peak corresponded to the 1 st and 3 rd peak on the DTA curve, respectively.
From examination of these results, the 1 st peak on DTA curves was attributed to the dissociation of two moles of water and 2 nd and 3 rd peaks on DTA curves were interpreted as due to the evaporation of MgCl2 solution.

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A new method of preparation of α-chloroisovaleric acid in excellent yield (78%) has been discovered as a result of chlorination of isovaleric acid with a mixture of gaseous oxygen and chlorine in the presence of chlorosulfuric acid and chloranil at 140° C. The effects of reaction conditions on the yield and conversion were discussed.

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Chlorine-sensitized photooxidation of tetrachloroethylene (TCE) was carried out in order to investigate the effect of oxygen pressure on the formation of trichloroacetyl chloride (TCAC). The results obtained are summarized as follows.
(1) TCAC is the main reaction product and the rate of formation of TCAC is of the first order with respect to TCE.
( 2 ) The relation between the rate constant of TCAC formation (kand the presmin) oxygen pressure (Po, : mmHg abs) at 40° C is given by the equation:
kpres(min-1) =5.71 X 10-5 P02-0.0283
( 3 ) The rate of reaction increases withan increase in the concentration of chlorine dissolved in TCE, and shows a maximum value in the range of 1.4 to 1.8 wt% of chlorine.
( 4 ) The rate constants for the formation of TCAC under atmospheric and higher pressure (by 300 mmHg), respectively, are expressed as follows:
katm (min-1) =4.53x 10 exp(030/R T)
kpres (min-1) =2.94x 108 exp( 070/R T)

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The reaction of diphenylketene N-p-tolylimine with various Schiff's bases was carried out by heating in toluene or xylene under reflux.
Schiff's bases in which R1=(CI-10)2N or CH₃O, H, CH₃O, or Cl, and R3=H gave four-membered-ring compounds (azetidine derivatives). Their reactivities and yield S varied over a wide range with the change in the substituent R1. When R. and R2 were both H and R3 was C8H₅, no product was obtained.
The mass spectra were discussed and a reaction mechanism has been suggested.

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Some of imidazole- and pyridine-carboxylic acids were reported in the previous paper to be converted to the corresponding trichloromethyl compounds by their reaction with phosphorus pentachloride in excess of thionyl chloride. In the present work, carboxyl groups of 4-chloropicolinic acid and 6-methylpicolinic acid were also converted to trichloromethyl groups under the similar condition, while those of 3-chloropicolinic acid, 6-chloropicolinic acid, pyrazine-2, 5-dicarboxylic acid, pyrimidine-4, 6-dicarboxylic acid and pyridazine-3, 6-dicarboxylic acid failed in the conversion, only giving the corresponding carbonyl chlorides.
The differences in reactivity of these carboxylic acids were studied in connection with the basicities of the heterocyclic nitrogens, and it was found that the acids with pK, higher than about 3.5 were successfully converted to the trichloromethyl derivatives.

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o-Acetylbenzophenone [1] reacted with aniline in benzene or in methanol in the presence of acetic acid to give a red pigment, C42H30N2 [5 d], mp 257° C, a deep blue pigment, C47F135N3 CH₃CO₂H [ 6 ], mp 275° C and two pale brown compounds, C41H30N2 [l2], mp 185° C and C611143N8 [l3], mp 310° C. However, from [1] and aniline in methanol in the presence of hydrochloric acid, the red pigment C5 dj and the blue pigment, (C41H₂91\12) +0- C3 dp were obtained. This blue pigment [3 d] was also prepared from [l2] and [I3] with hydrochloric acid.
On the basis of their spectra and chemical behaviors, the structures of these products were determined to be acetate of 1-anilino-1-[o- (a-phenyliminobenzyl) phenyl]-2- (2, 3-dipheny1-1- isoindolyl) ethylene C 61 bis-[l2] and tris- (2, 3-diphenyl-1-isoindolyl) methane [l3], respectively. From reaction mixtures of [1] and isopropyl- and cyclohexylamine in the presence of acetic acid, stable deep blue pigments, C_2C91-1, 8NOR 14 e, fD were isolated. By treating these reaction mixtures with hydrochloric acid, (C_2C91-119N2R2) +Cl- 1i3 e, f and [4 e, f] were isolated. However, in the presence of hydrochloric acid [1] did not react with these amines. [3 e, f] changed into [4 e, f] on standing in various solvents.
t-Butylamine did not react with [1] under the same conditions. The mechanisms of the formations of C 6 J and C4 e, fp from [3 e, f] were proposed.

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Trimethyl(trifluoroacetoxy)silane and diphenylbis (trifluoroacetoxy) silane reacted with alcohols at room temperature, to give the corresponding alkyl trifluoroacetates in good yields. With polyols such as ethylene glycol and glycerol, the diester and the triester were formed. The gas-chromatographic investigation revealed that the reaction proceeded via following three steps:
R3SiOCOCF3 ROH R3SiOR CF8CO₂1-1 R3SiOR CF3CO₂H
R3SiOH CF3CO₂R R3SiOH 1/2 (R3SiOSiR3 + H₂0)
The reaction of trimethyl (trifluoroacetoxy) silane with epoxy compounds also proceeded smoothly at room temperature. In this case, the ring-opening of the epoxide, followed by an insertion between Si and OCOCF3 occurred. Thus, with propylene oxide it gave a mixture of two isomers, CF3CO₂CH(Me)CH₂0SiMe8 and CF8CO₂CH₂CH (Me)0SiMe, , and with epichlorohydrin, it gave almost pure CF3CO₂CH₂CH(Cl-12Cl)0SiMe3.

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Cyclic methylphenyl(o-phenylenedioxy)silane [ 1 ] was synthesized by the reaction of methylphenyldichlorosilane with catechol in the presence of pyridine in 72% yield, and could also be prepared by the alcohol interchange reaction of methylphenyldimethoxysilane and catechol in 83% yield. The product [ 1 ], after distillation, crystallizes readily as a mixture of two isomeric dimers C_2CJ, mp 100-110° C. One of the isomer (mp 121° C) C_2C which was isolated by slow recrystallization, was assigned to the trans dimer on the NMR chemical shift (8(s1cH) O.53 ppm), and the other (mp 105° C) C_2C cp which was separated by rapid extraction from the mixture, the cis one (8(sicn3) 0.68 ppm).
The degree of polymerization in solution changed with time and finally reached a constant value between 1 and 2, which depends on the temperature and the concentration (Fig.1, Table 1). It was confirmed from NMR spectrum patterns (Figs.2, 3) that in solution, two isomeric dimers [2 t] and [2 c] were in equilibrium with monomer. Mole fractions of the monomer and two dimers at equilibrium state were obtained at various temperatures (Fig.4) and activa- tion energies (-4E) were found to be 7.5 kcal/mol for [2 t] and 8.3 kcal/mol for [2 c].

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An attempt has been made to correlate the carbon structure of cokes with the chemical structure of their raw materials.
Detailed physical and structural analyses were carried out on the extractive fractions (pyridine soluble and n-hexane insolube) of a series of pitches which were mutually different in cracking conditions and raw materials. At the same time their coking products were analyzed in terms of X-ray intensity factor of "Imax/B" (see, Fig.1) from (002) diffration patterns.
An electronic computer simulation based on the above results led to a simplified equation which would predict the structural differences of product cokes from chemical structure of raw materials.
Calculated results by using the equation coincided well with the intensity factor "Imax/B" from observed X-ray (002) diffraction patterns (Table 3). Thus the characterization of coke structure became possible based on the physical data and structural analysis of the raw materials.

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Molten zinc chloride is known as an e:: cellent catalyst for hydrocracking polynuclear aromatics such as coals and coal extracts when used in a high concentration.
In this study the catalytic properties of molten zinc chloride were elucidated from the reaction products of hydrocracking of simple and pure cyclic compounds which have similar molecular structure to coal extracts.
Polynuclear aromatic hydrocarbons were most readily hydrocracked, and the dehydroxylation also easily occurred. Compounds with hydroxyl group such as m-cresol were hydrocracked and hydrogenated, while benzene was not.
A characteristic absorption band observed in molten zinc chloride and anthracene system indicated the formation of proton or charge-transfer complex between molten zinc chloride and cyclic compounds, This complex is likely to take part in the reaction as a reaction intermediate, since cyclic compound with lower ionization potential reacted more easily.

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The kinetics of the oxidation of 2, 4Tdimethylpentane, a model compound of polypropylene, were studied at 70° C with azobisisobutyronitrile as an initiator. The kinetic order of the rate of oxidation on the substrate concentration was 0.76. This low kinetic dependence was interpreted by the contribution of intramolecular propagation. The ratio of the rate constants of intramolecular propagation to intermolecular propagation was estimated as about 100, which was in reasonable agreement with the literature value determined by product analyses. The kinetic order increased in the presence of added t-butyl hydroperoxide. It was suggested that kinetic study may be useful in elucidating the importance of intramolecular propagation in the oxidation of polypropylene, where the product analysis is quite difficult.

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The rheological studies were carried out on the hydrogels obtained from samples from seaweeds Gracilaria blogetti of Chile (Co) as well as Argentina (Ag. b.) and Gelidium amansii of Izu (Ig. a. ) of Japan under various alkali-pretreatment condition. Alkaline concentration during pretreatment varied within the range from 0 to 10% NaOH. The concentrations of gels p-repared were 1.5, 2.0 and 3.0 wt %.
Relaxation curves up to 4 hrs were obtained within the temperature range from 25° C to 55° C. These curves were represented. by a six-element mechanical model consisting of three Maxwell elements in parallel.
The results obtained are as follows; 1) The elastic modulus, E1 for the desulfated Cg, b. sample is nealy zero, but after pretreatment with a solution containing 2% NaOH it increases rapidly with increasing concentration of NaOH. The desulfated Ag. b. sample produces a strong gel in which the magnitude of E1 increases with increasing concentration of NaOH up to 4%, and then decreases slowly.2) The magnitude of E1 increases rapidly, when 3, 6-anhydrogalactose content in the samples is more than about 28%. 3) An apparent activation energy obtained from the temperature dependence of the longest relaxation time ri is nearly constant and about 5 kcal/mol. The effect of increase in alkaline concentration during pretreatment upon the ability of gelation in agar gels is explained in terms of the conformation of agar molecules in water.

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We discussed the behavior of epoxy groups in the curing reaction of ammoniacal resolewith epoxy resin using phenyl glycidyl ether (PGE), 2, 4-xylenol (2, 4-X) and its hydroxymethyl derivative (2, 4-XM) as models of above resin. And PhCHilTCH, PhOaH, (DBAO) which acts as catalyst was added tolhis, mixture as a model of intermediate reaction product of ammoniacal resol. The reaction conalitions were studied in the range from room temperature to 210° C. We confirmed by using NMR that, epoxy groups react mainly with phenoljc hydroxyl groups and form secondary hydroxyl groups, while hydroxymethyl groups in the resol produce methylene or dimethylene ether linkage by intramolecular condensation reaction. -We could-not, findany evidences for the reaction between epoxy and hydroxymethyl groups, although hydroxymethyl groups seemed to accelerate the reaction of epoxy groups with phenolic hydroxyl groups. Then we considered that proton released from phenolic hydroxyl groups as a result of intermolecular hydrogen bonding between hydroxymethyl groups and phenolic hydroxyl groups accelerated the above reaction.
DBAO promotes also the reaction of PGE with 2, 4-X or 2, 4-XM.
While with rising temperature, the ratio of reacted eP-ox-y groups to phenolic hydroxyl groups increases remarkably. This fact suggests that the epoxy groups react with secondary groups which are formed by the reaction between epoxy groups and phenolic hydroxyl groups.

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The mechanisms of reaction between 1, 3-diphenoxy-2-propanol (DP 2 P) and 2, 4-xylenol (2, 4-X) or its hydroxymethyl derivative (2, 4-XM) were discussed as a model of cross-linking reaction between secondary hydroxyl group i4 epoxy resin and amnoniacal resol type phenolic. /1 resin. In some cases PhCl-1-2NCH₂PhOali (DBAO) was added to the above mixture as a model of ammoniaclly catalyzed resol. The reaction conditions were studied in the range from 130° C to 210° C.
It was confirmend by using NMR that a reaction does not occur between secondary hydroxyl group in DP 2 P and phenolic hydroxyl group, while this secondary hydroxyl groups reacts with hydroxymethyl group in 2, 4-XM and forms 1, 3-diphenoxy--2-benzyloxypropane (DP 2 BOP). As the reaction proceeds, this structure decomposes into original secondary hydroxyl group (DP 2 P) and polymerized xylenols. The apparent activation energies of these reactions are 20 kcal/mol for formation reaction, and 24 kcal/mol for decomposition reaction, respectively.
The DBAO is not effective for the reaction of DP 2 P with 2, 4-XM while it accelerates selfcondensation of hydroxymethyl groups in 2, 4-XM.

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Polyquinazolinediones containing benzimidazole units were prepared by the solid phase polycondensation of O-phenylurethanes with diamino dicarboxylic acids. The solid phase reaction was investigated by TGA and DSC. The quinazolinedione formation involved the addition of amino group to the isocyanate group, formed by the thermal decomposition of phenylurethane, and the subsequent cyclodehydration of formed urea with acid. The polymerization proceeded in two stages, as reported previously in the reaction of bisphenylurethane with diamine. The intramolecular cyclodehydration was suggested to depend uppri the -easiness of mobility of the main chain of the polymer when compared it with that if model reaction., These polymers were thermally stable and partially soluble in organic sclvents. The T, of these polymers was estimated by DSC.

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The effects of additives on the polymerization of pyruvaldehyde [ 1 ] were studied by means of NMR spectroscopy at 20° C for 96 hr. The polymerization of [ 1 ] was initiated by acidic and basic compounds but showed no evidences of radical initiation.
In the presence of oxygen and light, acidic compounds were found to be present in [ 1 ] and to increase with time, and the polymerization was retarded by basic compounds or DPPH. Acetal linkage, acetyl group and small amount of acetoxyl group were found in the hard glassy polymer of Cl J in terms of 13C-NMR sperctrum.
Accordingly, it was assumed that the spontaneous polymerization of [1] was catalyzed by acidic compounds such as acetic acid which were produced by autoxidation of C and proceeded by means of cationic mechanism.

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The irreversible thermal shrinkage of nylon 6 fibers which were cold-drawn or heat-treated was measured by heating them successively from room temperature to 190° C.
The thermal shrinkage occurred in two stages, namely ( 1 ) in the range from room temperature to 60° C, and ( 2 ) starting at 90° C. The former was almost unaffected by the history such as cold-drawing or heat-treating. On the other hand, the latter was sensitively influenced by a difference in fine structure caused by cold-drawing and heat-treating. When these results were compared with temperature dependence of fine structure and of other physical properties, it was found that the thermal shrinkage is closely related to the release of strains and to the relaxation of molecular chains in amorphous region, associated with a breakdown of intermolecular hydrogen bond in this region. As crystallites would act as crosslinking points in crosslinked polymers and inhibit the relaxation and the motion of segments in amorphous region, the behavior of shrinkage seemed to be decided by the network-density in net-structure composed of crystallites as well as amorphous chains and by the extent of tension of amorphous chains. On the basis of this assumption, the mechanism of irreversible thermal-shrinkage for each specimen was discussed.

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Bisphenol type epoxide resin was cured with 4, 4'-diaminodiphenylmethane, and the process of curing was followed by observing the changes of, reactive groups, molecular weight distribu- tion, gel content, mechanical, dynamic mechanical and bonding properties of the system.
From these observations, process of curing of the system can be divided into three stages; namely ( 1 ) linear structure having molecular weight less than 1300, ( 2 ) non-crosslinked but branched structure having molecular weight less than 104 and ( 3 ) crosslinked structure.
In these three stages, good correlations were observed among mechanical, dynamic mechanical and bonding properties of the system. Chemical structures corresponding to these three stages were proposed and the correlations among above mentioned properties were also discussed.

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For the purpose of utilization of waste plastics, the product obtained from wet dehydrochlorination of poly (vinyl chloride) (PVC) was converted into an ion exchanger by treating it with sulfuric acid. This may be applicable as a collector of heavy metals. The wet dehydrochlorination products were prepared in the presence of NaOH (Product 1) or Fe (Product 2) under nitrogen atmosphere by the use of pelleted PVC or in the presence of NaOH and FeA (ProduCt 3) un-cter oxygen atmosphere by the use of powdered PVC. By sulfuric acid treatment sulfonic and carboxyl groups were introduced into the carbonaceous products. The amount of the sulfonic group introduced was nearly independent of treating temperature, reaching about 2: theq/g, Whereas the amount of the carboxyl group introduced increased with rising temperature. The ion 'exchangers containing 2 nieq/g of sulfonic, group and 2 meq/g of carboxyl group were converted into Na- or H-from, . and a solution containing 0.00612 moll/ of each Cua+, Zn²⁺, c42+ or Hg²⁺ was allowed to flow through them at SV=4, -5 to prepare break through curves. The presence of slow exchange part was noted in H-form and this part was inferred to be due to the carboxyl group.
The ion exchanger obtained from Product 1 showed the following order in the amounts of exchange: Cu²⁺>Cd²⁺, Ni²⁺, Zn²⁺>Hg1+ form Na-for and Cu"- >Zn²⁺, Cd²⁺>Ni2>Hg²⁺ for H-form. The same is true for the ion exchanger obtained from Product 2: Cd²⁺, Ni²⁺, Zn²⁺, Cu²⁺>Hg²⁺ for Na-form and Cu²⁺ >Cd²⁺, Ni²⁺, Zn²⁺>Hg²⁺ for H-form, and for the spherical ion exchanger form Product 3: Cu²⁺, Cd²⁺, Ni²⁺, Zn²⁺>Hg²⁺ for Na-form and Cul+, Cd²⁺, Ni²⁺, Zn1+>Hg²⁺. for, H-form.
Virtually ion exchange of Hg²⁺ does not occur on ion exchanger of H-form but beside ion exchange, such interaction as adsorption due to activated carbon is observed on ion exchanger of Na-form and the precipitation of mercury(I) chloride results on the surface of exchanger.

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Humic acid was obtained in excellent yield by oxidation of the char, which was derived from poly (vinyl chloride) (PVC) by thermal decomposition, with nitric acid. PVC (P: 830) was heated at a rate of 2° C/min in the ranges from 80° C to 300, 350, 400 and 450° C in a stream of air. The resulting char was found to have carbonyl groups, other oxygenated groups and aromatic structures in terms of IR spectroscopy. The yield of the char war 28.6-40.2% and the oxygen content of the char was 4.0-10.1%. The atomic ratio of hydrogen to carbon in the char decreased from 0.99 to 0.62 with rising temperature of thermal decomposition.
It was pointed out that lactone and/or ester linkages were formed in the char obtained at 450° C.
Humic acid was obtained in 82.4 and 90.5% yields from the char prepared at 300 and 350° C, respectively, by oxidation with 3 N nitric acid at 100° C for 5 hr. From the Char pr!pared at 400 and 450° C, humic acid was obtained in 93.6% yield by oxidation with 5 N nitric acid. The humic acid has similar properties to those of the regenerated humic acid obtained from coal by oxidation with nitric acid.
The humic acid has good adsorptive ability for heavy mdalic ions. By shaking 100 ml of 2x10' molf/ CdCl2 aqueous solution containing 0.1 g of the humic acid for 5 hr, 84.0-96.5% of Cizl ion was adsorbed on the humic acid.
The structure of the char from PVC and the properties of the humic acid were also discussed.

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The catalytic reduction of nitrogen oxide with ammonia in the presence of NO-02-H₂0-N2 and NO-S02-0g-H₂0-N, mixtures (N0 (2/3) NH, -+ (5/6)N2+ HP) was studied using a flow reactor (inside diameter: 12.0 mm) at atmospheric pressure and temperatures of 300 to 500° C (mainly 400° C).
The catalysts used were coprecipii'ated metal oxides (CuO-Al203, Fe2O^3-A1, 03 etc.), metal oxides treated ith S02-02-N2 mixtures, - and supported sulfates on alumina [CuSO₄-Al203, Fe2(SO₄), -Al203, FeSO₄-Al208]. The average diameter of the granular catalysts was 1.0 min. Inlet gas, concentrations ware 500 ppm NO-0--3000 ppm (mainly 1000 ppm) SO^2-334-1000 ppm (Plainly 667 ppm) NI-1370-45%, (mainl3n5670) 0, -0-20% (mainly 10%) H₂0-N2, and the total gas flow rate was 1000 Ncm3/min for 0.25 3.00 g of the catalyst.
Copper and iron sulfas were found to be excellent with respect to activity and selectivity at lower temperatures -below ca.400° C. It was also confirmed that t4e reaction between NO and NH₃ proceeded equimolally, and that higher as the concentration of 0, increased the -red-action' rate became. For copper sulfate catalyst the presence of SO s made the reduction rate higher.
From these results, the reduction mechanisms were described as follows.

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The research reported preliminarily (This Journal, 1974, 1819) was extended in more detail, using three separating columns whose effective length is one meter however whose inner diameters are different (8, 10 and 12 mm). The results obtained under an atmospheric pressure are as follows: ( a ) As shown in Fig.2, a stationary state of separation was reached after about half an hour, irrespective of column diameter. ( b ) Separation degree showed a maximum at wire temperature of ca.450° C (Fig.3) ( c ) The 10 mm column showed the most effective separation and its qo value became ca.104 at wire temperature of 290° C (Fig.4), ( d ) When a reservoir was attached at the top of the column and the gas mixture was supplied continuously, krypton could be highly enriched, e. g., ca.99% in the case when the initial concentration was about 10% (Fig.5). (e) High separation could be possible for Kr/Ar system equally for Kr/N2 system. It may be concluded that this method is promising and can be applied for the separation of krypton from air.

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Adsorption characteristics of phenol, p-nitrophenol, 2, 4-dichlorophenol, sodium dodecylbenzenesulfonate and sodium ligninsulfonate for spherically granulated activated carbon from coal have been compared with those of a commercial activated carbon from coconut shell.
Spherically granulated activated carbon is inferior to commercial carbon for adsorption capacities of phenol, p-nitrophenol and 2, 4-dichlorophenol. But spherically granulated activated carbon is superior to coconut carbon for adsorption rates and capacities of large molecular adsobates such as sodium dodecylbenzenesulfonate and sodium ligninsulfonate.
Effective diffusivities for phenot and sodium dodecylbenzetiesulfonate were calculated in terms Of the Boyd equation using the data of the adsorption rate obtained by agitating under the condition of intraparticle diffusion control. For spherically granulated activated, carbon, effective diffusivities of 220 me phenol and 150 me sodium dodecylbenzenesulfonate are 1.9 x108 cm²/sec and 4.3 x 10- cm²/sec, respectively. These values are larger than those of commercial coconut carbon.
In fixed bed adsorption, the calculated break point agreed well with the experimental data.

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The heat (411) and entropy (4, 5) of adsorption of water on iron(III) oxide hydroxides (a-, 8-, and T-FeOOH) were calculated from the adsorption isotherms and heats of immersion. The state of adsorbed water molecules on each iron(III), oxide hydroxides was discussed.
Values of z1H and z1S for a-FeOOH and T-FeOOH increased with the degree of crystallization, suggesting that localized adsorption takes place on the less crystallized samples. The values: of 414 and 4Sa, in an order of 8-Fe0OH<a-Fe0OH<r-Fe0OH, were discussed for the crystal structures of iron(III) oxide hydroxides.

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1, 1, 2-Trichloroethane (TCE) was coverted into 1, 1-dichloroethylene (VD) in a good yield by co-pyrolysis with ethers or alcohols on activated alumina.
The co-pyrolysis of TCE and ethers with bulky alkyl groups at low temperature proceeded slowly in the pores of alumina pellets. The contribution of the surface reaction appeared to increase as the reaction temperature rose. The reactivity of the higher ethers might also be increased owing to the inductive effect of larger alkyl groups. The -selectivity for VD decreased gradually with the increasing reaction temperature. The co-pyrolysis of TCE and ethers on activated alumina is a nucleophilic reaction and of first order in TCE.
The rate constants for TCE consumption in the co-pyrolysis with diethyl ether, n-Pr20 and n-Bu20 (kEt, o, kn-Pr2o and kn-Bu20, respectively) are expressed by the following equations.
kEt20/ (g-moljg hr) =0.360 ex p (500/R T)
len_p20/(g-molig hr) =1.52 x 104 exp(-19300/RT)
k0/(g-moligr) =2.12 x 105 exp(-21400/R 71)

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The contribution of the extra-column to the peak broadening was investigated by varying the length of column and connecting tube between column and detector.
For the system of 480 mm long and 2.1 mm i. d. column packed with Corasil I, 300 mm long and 0.8 mm connecting tube, and detector cell of 60 At/ in volume, peak broadening stemmed from the connecting tube and sample injection (septum injection) and proportions of contribution to peak broadening were 47.4% and 5.2%, respectively. Broadening in the detector was negligible.

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The effect of addition of tin (IV) chloride on the radical polymerization of styrene with benzylideneacetone or benzylideneacetophenone was investigated by using a, a'-azobisisobutyronitrile as an initiator. The addition of tin (IV) chloride increases the rate of copolymerization and the content of benzylideneacetone or benzylideneacetophenone unit in copolymers. The increase in added amounts of tin (IV) chloride results in a decrease in values of monomer reactivity ratios r1 and r2 and an increase in value of e2. These results would be due to the complex formation between tin (IV) chloride and benzylideneacetone or benzylideneacetophenone.

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Water soluble polymers were prepared by the reaction of poly (methyl acrylate) (PMA) with amino alcohols such as 2-aminoethanol (AE), 3-amino-l-propanol or diethanolamine, and examined in the removal effect of heavy metals from waste water by a foam treatment method. AE showed the best result among the amino alcohols used.
More than 99.9% of zinc was removed by the polymer prepared by the reaction of PMA with AE (molar ratio 1:5) in dimethylformamide at 130° C for 10 hours. More than 99% of copper or 98% of cadmium was, also, removed by this polymer.

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