The effect of added long-chain alcohol (cosurfactant) on the surface and interfacial tensions of fluorinated and ordinary surfactant solutions has been studied. When fluorinated cosurfactant was added to aqueous solution of fluorinated ionic surfactant, regardless of the kind of gegenions, low surface tension, 14-15 dyn/cm, appeared. Aerosol OT or suitable nonionic surfactant considerably reduced the interfacial tension until below 2 dyn/cm, because the Hydrophile-Lipophile-Balance (HLB) of the surfactant was optimum. On the other hand, the interfacial tension between oil and aqueous solution containing ordinary normal-chain ionic surfactant with cosurfactant was almost the same as that without it, despite the low surface tension appeared with cosurfactant. Aqueous solution of a mixture of fluorinated and ordinary surfactants spread over oil surface whose surface tension was only 18-20 dyn/cm.

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A thermal analysis technique was applied to the reduction of supported nickel oxide catalysts prepared by an impregnation. Alumina and silica were used as the supports. The catalytic activity was tested with the hydrogenolysis of propane. The reduction curves and X-ray analysis showed that over a wide range of nickel content, a part of the supported nickel is in the state of free nickel oxide. The morphologic forms of the catalysts before and after calcination were observed with a scanning electron microscope. Before the calcination, the support was found to be covered with nickel nitrate films in almost uniform thickness. On the other hand, octahedron crystals of nickel oxide were observed to be on the calcined sample. This result accords with that obtained from the reductioncurves and X-ray analysis. It was concluded that the presence of free nickel oxide characterizes the impregnation catalyst. Acording to CO chemisorption data, the surface area of exposed nickel on the silica supported nickel catalyst was markedly affected by reduction temperature. The nickel oxide in surface layers (NiO 11.7%) was almost completely reduced at 400°C. Over 400°C a crystal growth of nickel and the bulk diffusion of nickel were considered to be predominant.

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We have recently found that LaCo₅ absorbs a considerable amount of nitrogenin an atomic form above about 250° C. The absorbed nitrogen is hardly desorbed from LaCo₅ below 350° C. In the present study, several samples of LaCo₅ Nn, (n=0, 0.06, 0.10, O.18 and 0.24) were prepared and the hydrogenation of 1, 3-butadiene was conducted over the LaCo₅ Nn catalystsinthe temperature range-65 to-40°C. With the increase in n, the hydrogenation rate increased remarkably and the change of composition of the products from 1-butene-rich to 2-butene-rich (trans-2-butene cis-2v-butene) took place.
The isomerization and hydrogenation reactions of 1-ndash; butene were also conducted over the LaCo₅ Nn catalysts under similar conditions. The rate of the hydrogenation increased remarkably with the increase in n, while the rate of the isomerization was not affected by n. The hydrogen-deuterium equilibration reaction hardly took place during these hydrogenation reac-ndash; tions. These results led to the conclusions that the rate-determining step of these hydrogenations

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Selectivity to COS in vapor-phase hydrolysis of CS₂ over alumina catalyst at 230°C decreased remarkably with increasing contact time of the reaction, showing that the hydrolysis of CS, to CO₂ proceededvia COS as an intermediate. The catalyst was poisoned when pentene isomers were fed during the course ofthe reaction; the poisoning effect, despite scarcely affected by the feed concentration of CS₂, decreased with increasing concentration of water but rather increased with increasing electron-donating nature of pentene isomers. Exposure of alumina to 0₂ at elevated temperatures caused decrease in catalytic activity and in concentration of reduction sites at the surface which was estimated from the amount of SO₂-formed, but the basicity on the catalyst did not always decrease upon above pretreatment. Furthermore, the catalyst was temporarily poisoned by CO₂ and SO₂the poisoning effect followed the subsequent orde: S0₂ CO₂; as expected from their electron affinities. On the basis of these results, the nature of the active sites and the mechanism of the hydrolysis reaction are discussed. It was shown that reduction sites rather than so-called basic sites played an important role in the reaction. It is proposed that CS₂ and COS were adsorbed on the former sites to form negatively charged species, which were then hydrolyzed in terms ofwater adsorbed on acidic sites.

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Chemical composition of ancient coins may be useful to know the provenance of raw ore materials, technique of minting, route of circulation, and governmental policy or economical conditions of the epoch when they were minted. Thirteen elements (major: Cu, Pb, Sn, Zn, minor: Fe, As, Sb, trace: Co, Mn, Ni, Au, Ag, Se)in Chinese and Japanese ancient coins were determined by inductively coupled plasma-optical emission spectroscopy and instrumental neutron activation analysis. br
The results show that, in both Chinese and Japanese coins, a transition from Cu-Pb-Sn system to Cu-Zn system occurred in the 15-6 th century in China and in the 18 th century in Japan. Compositional rangesin Cu-Pb-Sn coins extend to 50-80% Cu, 15-35% Pb and 6-15% Sn, respectively, and there seems to be no systematic compositional change with a function of their ages. As to the Cu-Zn coins, the Cu to Zn ratio ofChinese coins is distinctly different from that of Japanese ones, being about unity for Chinese coins and 4 for Japanese ones. In general, Japanese coins are muchmore abundant in As ans Sb than Chinese ones. It is an important problem whetherthey are impurities of major elements or some components intentionally added in the course of minting.

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It has been found that organic bases such as pyridine, γ -picoline or imidazole accelerate considerably the complexation of cadmium (ll) with α, β, γ, δ -tetrakis (4-carboxyphenyl) porphine [T(4-CP)13] or α, β, γ, δ -tetrakis (4-sulfophenyl) porphine [T(4-SP) P]in aqueous solution. In 0.4% pyridine solution adjusted the pH to about 9, the complexation of cadmium (11) with T(4-CP)P is completed almost instantaneously and that with T (4-SP) P in 10 min even at room temperature. On the basis of these observation, two practical spectrophotometricmethods for the determination of cadmium at the ppb level have been developed: one method using T (4- CP)P in the presence of pyridine and the other using T(4-SP)P instead of T(4-CP)P have been established. Straight-line calibration curves were obtained up to about 250 ppb of cadmium for both the methods. The sensitivity for 0.001 absorbance was 0.248 ng Cd/cm² in the T (4- CP)P method and 0.25, ng Cd/cm2in the T(4-SP)P method. Interferences from other ions and salts in the T(4-CP)Pmethod were examined and the tolerance limit was shown for each of them. Only zinc(ll) interfered with the determination.

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Methods for the spectrophotometric determination of cobalt(III) and iron(II) with 4-hydroxy2-dimethylamino-5-nitroso-6-aminopyrimidine (HDNA) have been developed. Cobalt(III) reacts with HDNA to form a water-soluble yellow complex having an absorption maximum at 395 nm. Absorbance of the complex is constant over the pH range from 5.5 to 6.8. Beer's law holds over the range from 0 to 1.4 g/ml of cobalt (III), the molar absorptivity of the complex and the Sandell sensitivity for log(Io/I) =0.001 being 6.30 x 104 l. cm-1. mol-1 and 9.34 X 10-4 gcm-2, respectively. Nickel(II) and copper (II) interfere with the determination, but can be masked by the addition of 1% potassium cyanide solution. Iron(II) also forms a watersoluble blue complex with the reagent, having an absorption maximum at 660 nm. Absorbance of the complex is constant over the final pH range from 9.6_to 10.5. The solution containing up to 2.0 g/cm of iron (II) obeys Beer's law. The molar absorptivity of the complex and the sensitivity for log (Io/I) =0.001 are 3.05 x 104 l. cm-1. mol-1 and 1.85 x 10-3 pg. cm-2, respectively. Tolerance limits are given for 19 ions and 6 salts. The ratio of metal to HDNA is found to be 1: 3 for both complexes by the continuous variation method. The present method can be applied to the consecutive spectrophotometric determination of cobalt and iron, and of iron in zinc sulfate and aluminum alloys with a satisfactory result.

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A highly sensitive spectrophotometric method for Zn2+ has been established by using α, β, γ, δ - tetrakis(1-methylpyridinium-4-yl)porphine (TMPyP, H2L4+). The complex, ZnL4+, is formed within 1 min at room temperature in the pH range of 9.2 to 10.8. The Soret band of ZnL4+ (at 437.2 nm, ε = 2.28 X 105 l. mol-1. cm-1) seriously overlaps with that of the reagent (H2L4+, at 422.8 nm). However, the reagent blank can be successfully decreased by converting H2L4+ to its lead complex (PbL4+, at 476.4 nm). Procedure: take a sample solution containing up to 6 μ g of Zn2+ into a 25 cm3 volumetric flask, add 1 cm3 of 10-4 mol. dm-3 TMPyP solution and 5 cm3 of borate-sodium hydroxide solution (pH 9.2-10.8). Allow to stand for 5 min. Add 2 cm3 of 10-4 mol dm-3 Pb2+ solution and dilute to the mark with water. After 2 min, measure the absorbance at 437 nm against water within 2 hr. Beer's law is obeyed over 0-6 μ g Zn2+/ 25 cm3 and the sensitivity for absorbance O.001 is as low as 3.66 x 10-4 μ g Zn2+ cm-2, which is about 4.4 times as sensitive as that of the dithizone method. The coefficient of variation is O.97% for 4.17 μ g of Zn2+(ten determinations). Many metal ions interfere with the determination. However, Zn2+ can be selectively separated from these ions by dithizonate extraction in the presence of masking agents (bis (2-hydroxyethyl) dithiocarbamate for Cd2+, citrate for Fe2+ and Fe3+ and thiocyanate for Cu2+ Ni2+ and Pb2+), followed by back-extraction with 0.1 mol. dm-8 HC1 solution. Results are quoted for the application to the determination of Zn2+in tap water.

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The present paper deals with the study of the A. C. polarographic behavior of the complexes in the potential region where no charge transfer occurs. The complexes studied were [Fe. (bpy) ₃]²⁺, [Zn (bpy) ₃]²⁺, [Ni (bpy) ₃]²⁺, [Fe (phen) ₃]²⁺, [Zn (phen) ₃] ²⁺, and [Ni (phen) ₃] ²⁺, where bpy is 2, 2'-bipyridine and phen is 1, 10-phenanthroline. A. C. polarograms were recorded by Shimadzu polarograph RP-50 with an A. C. attachment BF-1. The complexes are adsorbed on the mercury electrode in the potential region of ca. -0.6-1.2 V vs. SCE (Fig.1). The peaks of the A. C. polarograms of [Fe (bpy)₃]²⁺, [Zn (bpy)₃]²⁺, [Ni (bpy)₃]²⁺ and [Fe(phen)₃]²⁺ are typical adsorption-desorption peaks (Figs, 1, 2). The competitive adsorption between organic analytical regents and their complexes were studied (Figs.3, 4), In the case of 2, 2'-bipyridine and its complexes, it is concluded that the ad- sorbability of the complexes overcomes that of 2, 2'-bipyridine, and the former expels the latter from the electrode-solution interface. While in the case of 1, 10-phenanthroline and its complexes, both of them coexist in the electrode-solution interface. The concentrations of the complexes in the solutions were calculated by using the stability constants, and it was found that the formation of the complexes was almost complete (Tables 1, 2). The effect of pH on the A. C. polarographic peaks of the complexes was explained in terms of the dissociation of the complexes (Figs.5, 6, Table 3),

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The mechanism of a rate promoted synergistic effect of trioctylmethylammonium chloride (R3RiNCl: Capriquat) on the extraction of iron (III) with 2-thenoyltrifluoroacetone (TTA=HE) was studied. The above effect of Capriquat at low chloride concentration region could be explained by a possible formation of R3R'NE. The effect of Capriquat became more remarkable by the presence of large amounts of chloride ion. The rate determining step in the extraction process of FeE3 into benzene was dependent on the TTA concentration used: FeCl3+R3R'N+R3R'NFeCl3(OH)+H+C1R3R'NFeCl3(OH)Cl-R3R'NFeCl4+OHE-R3R'FeCl3E+OHR3R'NFeC13E-E-R3R'NFeCl3E+OHThe final product obtained through the above reactions has already been confirmed to be FeE3 in the benzene phase by the authors (Bunseki Kagaku, 23, 495(1974)).

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Reactions of Cr (III) with dithizone (H₂dz) in acetone and of Cr (VI) with diphenylthiocarbazide in 10% (v/v) acetone-water mixture were investigated. The complex formed by these reactions is the 1: 1 cationic complex of Cr (III) with dithizone, [Cr (Hdz)]²⁺, which has an absorption maximum at 525 nm (molar absorptivity, ε = 2.95 x 10⁴ dm³. mol^-1. cm^-1) in acetone and at 530 nm (ε = 2.85 x 10⁴ dm³. mol^-1. cm^-1) in water. The complex reacted with dodecyl sulfate ion (ds^-) to form an ion-pair of [Cr (Hdz)] (ds) ₂, which was extracted into butyl acetate and isobutyl metyl ketone. But, it was not extracted into chloroform and benzene. The extracted ion-pair has an absorption maximum at 530 nm (ε = 2.85 x 10⁴ dm³. mol^-1. cm^-1) in butyl acetate. The partition coefficient, P= { [Cr (Hdz)] (ds) ₂} (o)/{ [Cr (Hdz)] (ds) ₂ }, was determined as 10^0.54 between water phase and butyl acetate phase.

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Hydrolysis products of iron (III) salt solutions of pH 1.5-1.8 were analyzed. It was found that α -Fe0OH precipitates in the presence of nitrate or bromide ions whereas β -Fe00H precipitates if the solution contains fluoride or chloride ions. NaFe₃(SO₄)₂(OH)₆ is obtained in the crystal form when the solution includes sulfate ions. Chemical state and crystal structure of the precipitates depend on the stability of Fe (III) complexes in the solution and on the concentration of anions. The contents of chlorine and bromine in the hydrolysis products were determined by means of thermal-neutron activation analysis. The γ -ray spectra were measured by a 1024 channel pulse height analyzer and a Ge (Li) detector. Atomic ratios, F/ Fe and Cl/Fe in β -Fe0OH, Br/Fe in α -Fe0OH, were found to be O.55, 0.15 and O.012, respectively. The desorption behaviours of chlorine from β -Fe00H and of bromine from cxF e0OH indicated that chlorine is included tightly whithin β -Fe00H crystal whereas bromine is adsorbed loosely on the surface of α -FeOOH crystal. The processes of iron(III) hydrolysis reactions in the various anions were also discussed from the standpoint of solution chemistry. MOssbauer spectra of β -Fe00H with fluolide ions and of α -Fe00H with chloride ions were taken at 78 K. The results indicated the slight difference in the internal magnetic field; 46.3 ± 0.3 T for the former and 47.2± 0.3 T for the latter.

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In the presence of both pyridine and triethylamine, aniline reacted with an excess of benzoyl chloride in chloroform at its refluxing temperature to give N-phenyldibenzamide in almost 90% yield. In the absence of either pyridine or triethylamine, however, no dibenzoylation occurred and only benzanilide was produced, indicating that both pyridine and triethylamine are required to promote the facile dibenzoylation.
To investigate the role of pyridine and triethylamine on the dibenzoylation, the conversion rates of the dibenzoylation of aniline with various molar ratios of pyridine and triethylamine have been studied by high pressure liquid chromatography (HLC) (Fig.1). The optimum molar ratio of pyridine and triethylamine on the dibenzoylation was found in the range of 1: 3-1: 4 (Fig.2). From the study on the conversion rate in the benzoylation of benzanilide by HLC (Fig.3), the dibenzoylation of aniline was found to proceed via benzanilide as an intermediate. Accordingly, the dibenzoylation mechanism has been proposed as shown in Fig.5.

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Cobalt catalyzed hydroesterification of oxiranes with carbon monoxide and methanol was studied as functions of catalysts, solvents, additives, reaction temperature and CO pressure to search for the optimum conditions for β -hydroxy esters, suppressing the side reactions (isomerization, deoxygenation, addition of alcohol, and polymer formation). Under the optimum conditions, methyloxirane[1], 1, 1-dimethyloxirane[ 2 ], and phenyloxirane [ 3 ], gave methyl 3-hydroxybutyrate, methyl 3-hydroxy-3-methylbutyrate, and methyl 3-hydroxy-2-phenylpropionate [ 4 ] as main products in 76% (cf. Run 7 in Table 1), 60% (cf. Run 32 in Table 3), and 32% (cf. Run 48 in Table 5) yields, respectively. In the case of [ 3 ], methyl 2-phenylacrylate and methyl 3-hydroxy-3-phenylpropionate were obtained besides [ 4 ] with the yields of 5% and 8%, respectively. The position of the addition of ester group to oxirane ring was reasonably interpreted in terms of steric and electric effects of the substituent group.

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Novel monoterpene alcohols, 1(7), 4(8) -p-menthadien-2-y1 acetate [6], tr ans-1 (7)-pmenthen-2, 8-diyl diacetate[ 9 ] and 1-p-menthene-7, 8-diyl diacetate [10], were obtained by the oxidation of 2(10)-pinene [ 1 ] with lead tetraacetate. trans-4(8)-p-Menthen-2-ol [12] and its cis-isomer [13] were obtained in equal amounts by hydrogenation of 1(7), 4(8)-pmenthadien-2-ol [6 a].1 (7)-P-Menthene-2, 8-diol [9 a] was easily converted into 1(7), 8-p-menthadien-2-ol [11].

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The rates and products of the ozonization of poly (vinyl alcohol) have been studied at 70°C in neutral and alkaline aqueous solutions. Ozonization of several model compounds and possible intermediates such as 2, 4-pentanediol, 4-methyl-4-hydroxy-2-pentanone and 4-methy1-3-penten2-one was also carried out. Poly (vinyl alcohol) was cleaved quite effectively by ozone to give ketones, carboxylic acids and aldehydes as the major products, the primary reaction being the oxidation of hydroxyl group to a ketone. Formic acid was the major carboxylic acid. It was found that the anomalous ozonolysis played an important role for a double bond conjugated with the carbonyl group. Ozonization in an alkaline aqueous solution was much faster than in a neutral solution and the major products were formic acid and acetic acid, the latter being formed through a β -hydroxy ketone by the reverse aldol type reaction and subsequent oxidation of acetaldehyde. The amount of carboxylic acids formed was larger than that of statistical chain scission of poly (vinyl alcohol). The mechanism of ozonization is discussed.

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The title compounds [ 3 ] were synthesized by the alkali treatment of 1-alkyl-2-(acylamino) pyridinium halides [2], prepared from 2- (acylamino)pyridines [ 1 ] and alkyl halides. The characteristic IR spectra of carbonyl group in [ 3 ] shifted to lower frequencies than those of [1] and [2]. The chemical shifts of methyl or methylene protones, attached to nitrogen in pyridine ring in [3] appeared at a lower field than that in 1-alkyl-2-iminopyridine [ 4 ].The solubilities of [3] in water were higher than those of the corresponding [1]. The pro-perties and behavior of the aqueous solutions of [ 3] were similar to those of the amine imides. And, some of [3], with the suitable alkyl and/or acyl groups, showed an excellent ability to lower a surface tension of the solution. Therefore, the significant contribution of zwitter ionic structure of [3], especially in a polar solvent, can be presumed from these results.

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Toward the autoxidation of liquid paraffin with air at 170 or 180° C, sulfides showed the synergistic effects as antioxidants in combinations not only with HPA but also with 1, 2, 4- trichloro-3 H-phenothiazin-3-one (PTO) which is the oxidative intermediate of HPA. In the latter combinations, the reduction of PTO to HPA was observed by means of UV spectra, which indicates that the regeneration of HPA contributes to the synergisms. The reducing agents of PTO were considered to be involved in the thermal decomposition products of sulfoxide which are produced by the oxidation of sulfide, From the additional observations that the sulfoxides have only low activity as synergists and p-chlorophenyl phenethyl sulfide behaves as an excellent synergist compared with phenyl or p-tolyl phenethyl sulfide, it was concluded that the rate-determining step for the formation of the unstable reducing agents is the oxidation of sulfides to sulfoxides, and that the oxidative stability of sulfides is one of the factors to determine the magnitude of the synergism. The synergisms between phenothiazine and sulfide at various concentrations were found to have some common features to those between HPA and sulfide, and the synergism in the former combination was also discussed from a standpoint of the redox reaction mechanism.

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Bisphenol, α, ω -diol and glycol type epoxide resins were cured with primary and tertiary amines. The relaxational behavior of these cured resins was followed by comparing tan δ curves with structural shemes of the cured systems. On the basis of the above observations, the relaxational behavior of the systems was interpreted to be responsible for the local mode relaxation and the relaxation induced from the hydroxy ether moieties. The new relaxational peak due to hydroxy ether moiety was detected by comparing tan δ curves of the cured systems with or without hydroxy ether moiety. Height of the peak was found to be proportional to the content of hydroxy ether moiety in the system.

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The reduction of NO with NH₃ and the oxidation of NH₃ with O₂ under coexistence of H₂ were investigated to establish the relations among gas composition, temperature, residence time, fractional conversion of NO, and the reaction mechanism in non-catalytic reduction of NO with NH₃. The experiments were carried out by using a flow reactor under an atmospheric pressure and at 600-1000° C. The composition of the inlet gas was 0-1500 ppm, NO-0-1500 ppm, NH₃-0-5000 ppm, H₂-0-5%, 0₂-0-13%, H₂O-N₂ and the residence time 0.37-2.9 Nsec.
The results obtained are as follows:
(1) Temperature range both for the reduction of NO and oxidation of NH₃ was reduced by adding H₂, and the higher the H₂ concentration, the larger became the effect. However, the fractional conversion of NO showed maxima at a certain temperature which depended on H₂ concentration. Above this temperature, by adding H₂ the oxidation of NH₃ to NO was promoted and the fractional conversion of; NO decreased considerably. It was difficult to obtain the high fractional conversion of NO under a coexistence of H₂.
(2) The same apparent stoichiometric reaction was obtained as in the absence of H₂: NO+ NH₃+ (1/4) 0₂ N2+ (3/2) H₂0.
(3) A chain reaction mechanism where OH radical was a main carrier was discussed as follows:
Since the oxidation of H₂ with 0₂ (H2+0 → H+ OH, H₂+ OH → H+ H₂0, H+02 → OH+ 0) occurred at a low temperature, and the oxidation of NH₃ (NH₃ → NH₂ → NH) with OH, H, and 0 radicals occurred at a low temperature (ca.600° C). And, it was deduced that NO was reduced to N₂ by the reaction NO+NH → N2+0H, and that above the temperature at which the maximum fractional conversion of NO occurred, the formation rate of NO became high in terms of the reaction NH+0₂ → NO+0H.

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The hydrogenation of sorbic acid catalyzed with cyanocobalt(II) complexes in the range of the CN/Co ratio from 2 to 8 has been studied at 30° C and 1 atm. Main products obtained were 2-hexenoic acid at CN/Co> 5 and 3-hexenoic acid at CN/Co < 4. Addition of potassium chloride to the complex increased the rate of hydrogenation remarkably. Analysis of the products -showed- that in the range of CN/Co from 2 to 4, 2-hexenoic acid was obtained in nearly the same amount as 3-hexenoic acid. However, for CN/Co> 4, the selectivity for 2- hexenoic acid increased with an increase in CN/Co ratio. Potassium hydroxide showed a different effect on the hydrogenation from the effect by potassium chloride. In this case, composition of the products remained constant in the range of CN/Co from 2 to 8. The effect of various neutral salts and bases on the hydrogenation has been studied.

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The isomerization of [Co (L- or D-asp) (L-his)] (asp =aspartate ion and his= histidinate ion) in water without catalyst has been studied. The changes in equilibrium mole fractions and rate constants of isomerization at various temperatures have been measured. The avarage activation energy of isomerization for [Co (L-asp) (L-his)] is about 250 kJ/mol and that for [Co(D-asp) (Lhis)] 180 kJ/mol. The rate of isomerization decreased at lower pH of solution, increased at higher pH, and decreased in D₂0 solution. The isomerization did not occur in any other organic solvents. The CMR spectra of five isomers have been obtained and suggested that all the carboxyl groups of asp and his have coordinated to Co(III), because the lower field shifts of carboxyl carbon signals are observed in comparison with those for the free ligands in basic solution.

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Rose Bengal has a catalytic activity for the nuclear bromination of toluene. Thus, 10 ml of toluene containing 100 mg of Rose Bengal was treated with 0.98 ml of bromine at 30°C for 5 hr to give p- and o-bromotoluenes (p-/o-=1.5) in ca.90% yield. Without Rose Benga4l p- and o-bromotoluenes (p-/o-=1.6) and benzyl bromide were produced in yields of 17% and 74%, respectively.

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