The molar excess enthalpies HE of the title mixtures have been determined by using twin-microcalorimeter of heat-conduction type which requires only 10 cm³ of each component liquid for a series of runs over the whole range of mole fraction.
The H^E for (carbon tetrachloride+CH₃SOCH₂SCH₃) is endothermic as shown in Fig.1, having a maximum of 286 J·mol^-1 at mole fraction x₂=0.28, of CH₃SOCH₂SCH₃. This maximum value is comparable to the one reported for (carbon tetrachloride+DMSO), For (chloroform+CH₃SOCH₂SCH₃) and (dichloromethane+CH₃SOCH₂SCH₃), both H^E's are exothermic. The minimum values of H^E is -2.38 kJ·mol^-1 at x₂=0.38 for the former mixture and is -895 x₂ at x₂=0.45 for the latter.
For (chloroform +CH₃SOCH₂SCH₃), an equilibrium constant K₁ expressed in terms of mole fractions and standard enthalpy ΔH₁° of formation of 1: 1 associated complex, CH₃·(CH₃SCH₂)SO…H-CCl₃, have been evaluated to be K₁=2.2 and ΔH₁°=-8.7 kJ·mol^-1, by assuming an ideal mixture of monomeric molecules and their associated complexes. Enthalpic stabilization by hydrogenbonding between chloroform and CH₃SOCH₂SCH₃ molecules is smaller than that between chloroform and DMSO molecules by about 20 per cen.

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Inhibitory effects of organic substrates have been studied on the hydrolytic degradation of 12-molybdophosphoric acid (PMo₁₂) in concentrated aqueous solutions at elevated temperature. 10 wt% of dioxane was adequate to inhibit the degradation of PMo₁₂ in 67 wt%solution at 90°C. The effect of dioxane is ascribed to the equilibrium shift toward PMo₁₂ in the hydrolysis of PMo₁₂ to 9-molybdophosphoric acid (PMo₉) by studies using ³¹P-NMR. Other oxygen-containing substrates (“OS”) such as t-butyl alcohol (TBA), tetrahydrofuran etc. were similar character to dioxane. The addition of H₃PO₄ together with “OS” reduced their amount required for inhibiting the precipitation reaction. The effect was interpreted as being due to the equilibrium shift toward PMo₁₂ in the 18-molybdodiphosphoric acid (P, Mo, B) formation reaction from PMo₁₂ and 1131304. The inhibitory effect on degradatio n depended on the “OS” used, and can be associated with the interacting forces of “OS”to PMo₁₂ which were determined by the extent of the equilibrium shift in the hydrolysis: PMo₁₂ _??_ PMo₉, using ³¹P-NMR.
The electron donating property of “OS” can be attributed to the interaction.
The increasing order of the affinity of diethyl ether to vari ous heteropolyacids was determined as SiMo₁₂∼SiW₁₂<<PMo₁₂∼PW₁₂, based on the amount of diethyl ether dissolved in the -aqueous heteropolyacid layers.
The heteropolyacid-“OS” in teraction is considered to require water molecule for the interaction. A proton could play an important role together with water for the interaction between diethyl ether and heteropolyacids. The interactions between PMo₁₂ and either TBA or dioxane, however, were preserved even in the very low acidic solution.

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The preparative methods of the Raney-type catalysts for decomposition of methanol were examined. Ni-Al and Ni-Cu-Al alloys were used as catalyst raw materials.
The catalyst oxide precursors were prepared by leaching the Raney alloys w ith dilute NaOH aq. soln., followed by oxidation and calcination in air. Addition of Cu and K as promoter were carried out by impregnation of the oxide precursors with Cu²⁺ ammine complex ion and K₂CO₃ aq. soln., respectively. For Ni-Al₂O₃ catalyst prepared from Ni-Al alloy, low selectivity toward decomposition of methanol was observed, and extensive dea ctivation and carbon deposition occured. Addition of Cu, the constituents of resulting catalyst were copper-rich Ni-Cu alloy, Ni and η-Al₂O₃, was found to improve selectivity toward decomposition of methanol markedly and to reduce deactivation and carbon depositio n to some extent. For Ni-Cu-Al₂O₃ catalyst prepared from Ni-Cu-Al alloy which consists of nickel-rich Ni-Cu alloy, Cu and η-Al₂O₃, decomposition of methanol and formation of dimethyl ether were predominant. And deactivation due to reversible poisoning by reaction product and carbon deposition was observed (Fig.3). On the other hand, the deact ivation of the Cu added catalyst, as prepared by impregnation of Ni-Cu-Al₂O₃ precu rsor with Cu²⁺, was found to be due to reversible poisoning. And the activity of the cata lyst was higher than Ni-Cu-Al₂O₃ catalyst (Table 3). For the catalysts impregnated with K₂CO₃, the suppression of dimethyl ether formation and the elimination of reversi ble poisoning were observed (Fig.4). For the catalysts impregnated with Cu²⁺, carbon d eposition was suppressed.

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The reduction of NO_x with NH₃ in SO₂-containing gas on activated carbon and V₂O₅-loaded activated carbon was investigated by using a small scale fixed-bed reactor at 408 K. Various gases consisting of NO, SO₂, NH₃, H₂O and O₂ were subjected to the experiment. Activated carbons tested in this experiment were produced from coals which were used in power generation plants.
The amount of NO adsorbed on activated carbon was very small, whereas the removal efficiency of NO_x increased slightly, when O₂ was added to NO. It was assumed that NO was oxidized to NO₂ and then adsorbed on activated carbon. By adding NH₃ in a mixture of NO and O₂, the NO_x removal increased. It increased with the increase of NH₃/NO mole ratio, but it leveled off at NH₃/NO mole ratio larger than 1.
The removal efficiency of NO_x over activated carbon decreased with the increase of SO₂ concentration, whereas activated carbon impregnated with V₂O₅ showed higher activity than the original one. It was found that activated carbon impregnated with V₂O₅ had a higher activity for simultaneously removing SO₂ and NO_x in flue gas.

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Dynamic behavior of Pt, Pd, and Rh catalysts supported on α-Al₂O₃ was investigated with model gas systems such as CO-O₂-NO-C₃H₆, CO-O₂-NO, C0-O₂-C₃H₆, and CO-O₂ at stoichiometric conditions. The cycled feedstreams were prepared by the alternative injections of CO and 0₂. The period of cycled feed composition fluctuation was varied from O.2 to 2 s. These studies were complemented by the chemisorption measurements of CO and C₃H₆ and the CO₂ formation rates for various CO or O₂ injection periods from 0.1 to 0.5 s.
The amount of CO₂ formation was increased when the O₂ injection period wa s increased. On the contrary, it was not increased when the CO injection period was increased (Figs.13and 14). The favorable effect of O₂ injection is due to the elimination of the strongly absorbed molecules such as CO and C₃H₆.
From the experimental studies of the periodic operation effect for various gas compositions and temperatures (Table 2 and 4), it was found that the periodic operation effect was effective in preventing the self-poisoning effect of CO and C₃H₆, which were predominant at low and high temperature, respectively. The order of periodic operation effect was Pt > Pd > Rh, corresponding to the order of their susceptibility to self-poisoning. t Study on Automotive Three-Way Catalysts. IV.

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An amperornetric titrimetry for the determination of methionine and methionine sulfoxide was developed. Detecting the end point by the reduction current of iodate(titrant) at a rotating platinum electrode (2000rpm) applying +0.6 V vs. SCE, methionine and methionine sulfoxide could be titrated at about 45°C with 0.05cm³ portions of a standard pot a ssium iodate solution at intervals of 5-40 s by using a base solution of 3 mol·dm^-3 hydrochloric acid saturated with sodium chloride. Methionine (0.15-29mg) and methionine sulfoxide (0.34-6.5mg) were determined with relative errors of less than 5%. The best results were obtained in the sampling range of 1.5-29mg for methionine and 1.6-6.5mg for methionine sulfoxide with relative errors and coefficients of variation of less than 0.3%. The recommended procedure is as follows. Measure 15cm³ of 10 mol·dm^-3 hydrochloric acid, 12g of sodium chloride and 25cm³ of water into a 100cm³ titration cel l. Heat it to about 45°C and add exacetly 10 cm³ of an aqueous solution containing 2-3mg of methionine or methionine sulfoxide. Titrate immediately the resultant solution at about 4 5°C with 0.05cm³ portions of 10^-2mol·dm^-3 standard potassium iodate solution at intervals of 5s amperometrically. Effect of concomitant compounds were also investigated.

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In order to simplify and know more in detail about the complex mechanism of ozonolysis of lignin, veratrole and guaiacol were chosen as the model compound of the aromatic moieties of the lignin and ozonolyzed in 50% aqueous dioxane at pH 9 and 4. A sample was analyzed by high-performance liquid and gas chromatography to give the variation curves of yields of ozonolysis products over the reaction time After 3 h the ozonolysis of veratrole (initial concentration 0.06 mol/l) at pH 4 produced oxalic acid (0.003 mol/l), methyl hydrogen oxalate (0.013), dimethyl oxalate (0.015), and dimethyl muconate (0.001)of which amount had reached the maximum value 0.006 mol/l after 1 h. Maleic acid and its monomethyl ester were minor products (10^-3 mol/l). Guaiacol was ozonolyzed at pH 4 to give mainly oxalic acid and its monomethyl ester besides other minor products such as muconic acid, maleic acid, their methyl esters, catechol, and methoxyhydroquinone. The ozonolysis of veratrole and guaiacol at pH 9 gave also methyl hydrogen oxalate as main product and mono- and dimethyl esters of muconic acid in very low yields. Slight amounts of guaiacol and catechol were detected in the ozonolysis of veratrole and guaiacol, respectively, indicating the formation of hydroxyl group by cleavage of ether linkage of methyoxyl group with ozone. The ozonolysis of muconic acid in water at pH 9 produced formic acid and glyoxal at the earlier stage of reaction and glyoxylic acid followed by formation of oxalic acid at the later stage after 5 h. The main route of ozonolysis of the model compounds is considered to be the direct formation of oxalic acid and its methy esters from the aromatic rings rather than oxalic acid formation via the intermediates, muconic acid and its esters, formed by C₁-C₂ bond cleavage of the aromatic rings.

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Heating phenyl isocyanate [PI] with phenyl glycidyl ether [PGE] in dimethyl sulfoxide [DMS0] in the presence of 1-(2-cyanoethyl)-2-phenylimidazole [B] as a catalys t gives mainly 1, 3, 5-triphenyl isocyanurate [TPI]. At first, 1, 3-diphenylurea [DPU] is formed by the reaction of PI with a very small amount of water which is contained in DMSO, and then the trimerization reaction of PI proceeds. This reaction was kinetically investigated below 100°C. This trimerization reaction exhibits a definite induction period before the reaction starts, and is first-order in PI (fig.4, Table 1).
This trimerization mechanism would be expressed as follows;
The following suggests the possibility of the proposed mechanism.
( 1 ) Rate constants are linear with initial concentration of PGE or B (Figs.6 and 7).
( 2 ) When PGE is preheated with B in DMSO, a very small amount of PGE decr eases and electric conductivity of the mixture solution increases approximately by a factor of 4. And then both remain unchanged for several hours (Fig.9). This results suggest the possibility of the formation of ions.
( 3 ) In the trimerization of PI in the presence of the foregoing catalytic system, rate constants rem in unchanged but induction periods decreases (Table 3).

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EI mass spectra of some fused ring 1, 3-dialkyl-1, 3, 5-triazine-2, 4(1H, 3H)-dione derivatives (abbreviated as TADO) which consist of one 4-quinolone or 4-quinazolinone derivative and two alkyl isocyanate moieties have been measured by means of low resolution, high resolution, and linked scan methods. In the case of a reference type of TADO, [1], the molecular ion (m/z 259) was the most abundant one and an important fragment ion was mlz 145 [M-2 MeNCO] from which further fragmentations occurred. The loss of one molecule of RNCO was not an important pathway in the fragmentation of [1]. However, the structural effects of ( 1 ) aza-replacement, ( 2 ) alkyl-substitution, and ( 3 )dehydrogenation of [1] on the initial EI fragmentation process have been found in the three possible modes of loss of one RNCO moiety from the triazinedione ring. It was considered that each structural change, ( 1 ), ( 2 ) or ( 3 ), makes one or two different RNCO-loss modes important to give a different ELMS pattern.
FAB mass spectra of TADOs have been measured with glycerol matrices where the protonated molecular ion [M+1] peaks were observed in most cases. FAB quantitative measurements were applied to follow a thermal decomposition process of a thermally labile derivative, [8] in a DMF solution (Eq.1), and the first order rate constant was derived.

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The reaction of 2-methyl-6-xylyl-2-heptanol and 6-methy1-5-xyly1-2-heptanol prepared from m-xylene with the acid catalysts afforded tetralin mixtures consisted of 8-methylcalamenene [6A] and its isomer [7A] as a major product, respectively. By the similar treatment 2-methyl-6-xylyl-2-heptanol and 6-methyl-5-xylyl-2-heptanol prepared from ρ-xylene yielded the tetralin [8A] as a main product. The catalytic hydrogenation of 1, 2-dihydro-4isopropyl-1, 6, 8-trimethylnaphthalene, 3, 4-dihydro-4-isopropyl-1, 5, 7-trimethylnaphthalene, and 3, 4-dihydro-4-isopropyl-1, 5, 8-trimethylnaphthalene afforded the tetralins [6B], [7B]and [8B] as an alone product, respectively.
The trans-configuration are te ntatively assigned to the tetralins [6A], [7A] and [8A]and the cis-configuration to the tetralins [6B], [7B]and [8B].
8-Methylcadalene and two isomeric isopropyltrimethylnaphthalenes were also synthesized.

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In order to clarify a relationship between anionic moi ety of alginate and development of the antitumor activity, we attempted to obtain a reduced alginate with both high molecular weight and high degree of reduction. For the purpose, a sodium alginate was reduced under various conditions applying the method of Taylor et al. The polyuronide was first allowed to react with water-soluble carbodiimide; 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC), and then the polyuronide-EDC mixture was reduced on addition of sodium borohydride in the following two procedures;(I) with keeping the reaction mixture at pH 7.0 and then by stirring the mixture for 1 h at room temperature after the addition had been completed, and (II) without controlling the pH and then by heating the mixture at 50°C for 2 h after completion of the addition. The degree of reduction of the alginate obtained by the procedure(II) was slightly higher than one by (I). And the molecular weight of the alginate obtained by procedurean was four times as large as one by (I). Therefore, we reduced alginate by the procedure(H). As the amounts of EDC increased, so the degree of reduction of alginate increased to the constant value (ca.68%), whereas its molecular weight decreased to one sixth of the original one. When the amount of EDC employed was more than 2.6 in the molar ratio of EDC/uronic acid in alginate, the degree of reduction of guluronic acid residues was found to be higher than that of mannuronic acid ones in the obtained alginates.

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The polymerization of methyl methacrylate (MMA) in itiated by several sex hormones (Fig.1) and its analogous compounds was studied as an example of radical rea ction of physiologically active substances in vitro. Although the polymerization was not initiated by these compounds alone, it was found that progesterone (Pro), testosterone (Test), and 11-ketoprogesterone (Kpro) were able to show the initiating activity of polymerization by adding small amounts of FeCl₃ (the polymerization was retarded in above a certain quantity; Table 1). The overall activation energies for the polymerization were estimated to be 48.9 kJ·mol^-1 (for Pro system), 57.3 kJ·mol^-1 (for Test system), and 47.7 kJ·mol^-1(for Kpro system), respectively. The polymerization of MMA by Pro or Kpro system was kinetically studied in methanol, keeping the ratio of hormone to FeCl₃ constant ([Hormone]/[FeCl₃]=50; Table 2, Figs.4 and 5), to give the following equation of polymerization rate (R_p):
R_p=k[MMA] [Pro or Kpro+FeCl₃]^0.5
The initiating radical was assumed to be produced through the redox reaction between the hydrogen at 17-position of steroid ring and Fe³⁺. Follicular hormones having phenolic hydroxyl group acted as a terminator for the radical polymerization.

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As for the activation energy, E_p^≠, of the propagation step in radical polymerization, Eq.1 was deduced,
where, A and B are constant, andE_SOMO and E_LUMO are eigenvalues of SOMO (radical) and LUMO (monomer), respectively. The reason can be explained from Figs.1, 2 and 3 (Text). In order to derive Eq.1 theoretically, the following discussion was progressed.
According to Nagase et al. the perturbation formura for the addition reaction of a radical Ciwith a monomer CH2=CH-R is expressed by Fig.4 (Text). The first perturbation occurs between SOMO and HOMO (the perturbation energy is ΔE₁). And the second perturbation occurs between the newly generated SOMO and LUMO (the perturba tion energy is ΔE₂). The authors pointed out that in the first perturbation the electron flows from the monomer to the radical, but in the second perturbation the electron flows inversely from the radical to the monomer.
It is considered that the electro n transfer is one of the necessary conditions for the reaction. And the electron transfer is estimated to be proportional to the largeness of (ΔE₁-ΔE₂).
Thus, Eq.10 was proposed.
E_p^≠=C-γ(ΔE₁-ΔE₂) (10)
In this equation, C and γ are constant and ΔE₁ and ΔE₂ can be calculated by Eqs.6and 7 in the text.ΔE₁ is almost constant at 1.9±0.4 eV. Accordingly, Eq.10 can be converted to Eq.3 through Eq.11, in which ΔE₁ was neglected by its small value compaired with Esomo.

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Effect of iron or copper ions on polymerization of methyl methacrylate (MMA) initiated by the hydroxylamine-H₂O₂ redox system was investigated at 40°C. The rate of polymerization increased significantly in the presence of a trace amount of iron(II) or iron (III), whereas it decreased considerably in the presence of a trace amount of copper(II) (Figs.1, 2and 4). The concentration of H₂O₂ or hydroxylamine (HA) decreased rapidly with time in the presence of iron(II) or iron(III), while in the presence of copper(II) their concentration decreased slightly. In addition, in the presence of copperap the decreasing rate of HA or H₂O₂ was smaller (HA) or larger (H₂O₂) than that in the absence of copper(II)(Figs.5 and 6). These results suggested that (1) the reaction of H₂O₂ with HA followed the formation of free radicals is enhanced by iron(II) or iron(III) and hindered by copper(II), and (2) H₂O₂ decomposes slowly without the formation of free radicals rather than reacting with HA in the presence of copper(II).

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A multifunctional polymeric photosensitizer having pendant photosensitizing and substrateattracting groups was synthesized by radical copolymerization of photosensitizer monomers such as 4-nitro-1-naphthyl methacrylate and basic monomers such as 2-(dimethylamino)ethyl methacrylate using 2, 2'-azobisisobutyronitrile in N, N-dimethylformamide or benzene.
The photochemical reaction of methyl cinnamate with these polymeric photosensi tizers was carried out in THF. From the results of these investigations, it was found that the multifunctional polymeric photosensitizer with the pendant substrate-attracting group, which has dipole-dipole interaction between the substrate-attracting group in the polymer and methyl cinnamate, reveals an excellent photosensitizing activity compared with the conventional polymeric photosensitizer having only photosensitizer and with the corresponding low-moleculare-weight photosensitizer. In addition, the multifunctional polymeric photosensitizer has a higher photosensitizing activity at the larger content of the substrateattracting groups.

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A fuel of coal-water mixture (hereinafter simply called CWM) is preferable to be combustible without being dehydrated. For such an advantage, it is necessary to increase the coal content of CWM by using an appropriate type of coal. The CWM samples with various types of coal were prepared in order to examine how the coal composition had an effect on concentrating the CWM. Following results were obtained:
1) Types of coal remarkably varied the maximum coal concentration (hereinafter called MxCC) of the CWM. However, a highly-loaded CWM could easily be prepared by the use of good dispersants. (Table 1-5)
2) The MxCC of CWM was lowered with an increase in the number of oxygen atoms or of water molecules per 100 carbon atoms in coal. These factors were very closely correlated with each other. (Figs.1-4)
3) The MxCC of CWM was also lowered with an increase in the water wet tability of coal. (Figs.5, 6)
4) The tendencies mentioned in 2) and 3) were also found when such dispersa nts as sodium salt of formalin naphthalenesulfonate condensate and (N-polyoxyalkylene)polyethy lene imine were used. (Figs.1-6)

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For improving the wear resistance of chemical composite coating of Ni-P, the chemical composite coating of Ni-P-SiC has been investigated. The proper. composition of the electrolytes and the factors which affect the properties of the codeposited composite coating are described. The optimum conditions are as follows: temperature 86°C, pH 4.6, deposition rate 8-12 μm·h^-1, mean diameter of SiC 3 μm, and the amount of additive 5 g·l^-1. The hardness and resistance of the coating to wear were also measured. The dispersion state at, the surface and the cross section of the coating have been examined using a scann ing electron microscopy.

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A new type of metal imaging system is reported.
When n-type semiconductor electrodes we re illuminated in the electrolytic solution which contained aromatic compounds, a thin organic layer was formed on the irradiated region of the surface. The deposition was found to be effective for changing the rate of zinc evaporation. The image formed by the photoelectrolysis (latent image) could be developed by selective zinc vapor evaporation in a vacuum chamber and brought about a fine zinc pattern on the semiconductor electrode.
The mechanism of the zinc pattern formation was studied by measuring the rate of zinc deposition on the semiconductor surface.

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The decomposition pressures (P_NH3) of the reaction, (NH₄)₂HPO₄⇔NH₃+NH₄H₂PO₄, were measured at temperature range from 80°C to 165°C by using a Bourdon-type sickle gauge. The temperature dependence of the decomposition pressures was given by the following equation.
log P_NH3(Torr) =13.20-4.70×10³/T(T=353-438 K)
The decomposition pressures of ammonium dihydrogen phosphate were similarly measured, and it was found that the thermal decomposition took place evidently at higher temperature than 166°C and did not participate significantly with the decomposition equilibrium of diammonium hydrogenphosphate in a temperature range below 165°C.

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The thiolysis of acid halide-N, N-dimethylthioformamide (DMTF) adducts has been investigated. In this reaction, aliphatic, alicyclic, aromatic, substituted aromatic acid halides and these dibasic acid halides gave the corresponding thiocarboxylic acids in quantitative yield.
Thiocarboxylic acid, in the presence of hydrogen sulfide, was preferentially generated from the reaction of the adduct with acid halide via acid thioanhydride rather than the direct cleavage of C-S bond of the adduct.

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When equimolar solutions of DMSO and TiCl₄ in carbon tetrachloride were mixed, DMSO-TiCl₄ (1:1) complex (complex A) (mp 218.5 °C) deposited immediately in 91.5 % yield. The oxidation of benzoin [1] ρ-toluoin [2], o-anisoin [3] and ρ-anisoin [4] with complex A gave the corresponding benzils in more than 92% yield under mild conditions [room temperature, 15 h, molar ratio (complex A/benzoins) =0.25] (Table 1). The reaction of [1] with complex A was accelated by adding slight amounts of tribenzylamine (Table 1).

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Phenoxymethyllithium, which was prepared from t ributyl (phenoxymethyl) tin by tinlithiumexchange reaction, reacted with various electrophiles to give alkylation and/or condensation products in good yields.

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