bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study of Organo(2,2′-bipyridine)nickel Complexes. III. NMR Studies on the Interaction of Dialkyl(2,2′-bipyridine)nickel with Solvents and Olefins
Authors: Yamamoto Takakazu , Nakamura Yoshiyuki , Yamamoto Akio 
Published: July 2006

Abstract
The 1H-NMR spectra of NiR2(bpy)(bpy=2,2′-bipyridine; R=CH3, C2H5, and C3H7) and Ni(C2H5)2(bpy)–olefin systems (olefin=acrylonitrile and acrylaldehyde) have been studied in a temperature range from −70 °C to 80 °C. The temperature dependence of the chemical shifts of ethyl and 2,2′-bipyridine protons of Ni(C2H5)2-(bpy) in non-aromatic solvents (acetonitrile, N,N-dimethylformamide, acetone and tetrahydrofuran) is analyzed on the basis of the formation of 1: 1 solvent-solute complex. The formation constant of the 1: 1 comples, K1, and the thermodynamic parameters ΔF1°, ΔH1°, and ΔS1° are given. The NMR spectra of NiR2(bpy) in aromatic solvents show the aromatic induced solvent shifts, and the chemical shifts of CH2 and CH3 of Ni(C2H5)2(bpy) coincide at 76 °C in benzene to give a sharp singlet peak. The 13C-NMR spectrum of Ni(C2H5)2(bpy) in benzene shows a triplet at 10.63 ppm (CH2, J(13C–H)=132 Hz) and a quartet at 15.97 ppm (CH3, J(13C–H)=128 Hz). The formation constant of Ni(C2H5)2(bpy)(olefin), K2, and the thermodynamic parameters, ΔF2°, ΔH2°, and ΔS2° have been obtained from the temperature dependence of the NMR spectra of the Ni(C2H5)(bpy)–olefin systems. The values of the chemical shift differences between CH2 and CH3 (Δ=δCH2–δCH3) for Ni(C2H5)2(bpy), Ni(C2H5)2-(bpy) (acrylaldehyde), and Ni(C2H5)2(bpy)(acrylonitrile) are −0.30, 0.94 and 0.83, respectively. The increase of the values of Δ by the coordination of the electronegative olefins with nickel is regarded as indicating the increase of the electronegativity of nickel due to the back-donation from nickel to the olefin.
Alkaloids of Rhazya stricta Decaisne: Studies on Rhazinaline and Geissoschizine
Authors: Chatterjee Asima , Banerji Avijit , Majumder Priyalal , Majumder Rekha 
Published: July 2006

Abstract
Chemical investigation of the basic principles of the leaves of Rhazya stricta Decaisne led to the isolation of a number of indolic bases. The studies on two of these, viz., rhazinaline and geissoschizine are described. Rhazinaline, a new alkaloid, has been characterised as 16-formyl-16-epistrictamine. A detailed spectroscopical study of geissoschizine, which had not been previously isolated from a plant source, was carried out confirming the previous structural assignment. The isolation of this alkaloid from a plant source is important from a biogenetic viewpoint, since geissoschizine is one of the key preformed intermediates in the biosynthesis of C19–C20 indole alkaloids.
Rearrangement of 5-Isopropenyl-2-norbornene to 5-Methyl-3a,4,7,7a-tetrahydro-1H-indene
Authors: Iwase Shoji , Nakata Michihiro , Hamanaka Sawako , Ogawa Masaya 
Published: July 2006

Abstract
The Diels-Alder reaction between cyclopentadiene and isoprene gave predominantly endo- and exo-5-isopropenyl-2-norbornenes and also cis-5-methyltetrahydro-1H-indene produced from the endo-product by Cope rearrangement.
The Structure of the Cyclodextrin Complex. III. The Crystal Structure of the α-Cyclodextrin-Sodium Benzenesulfonate Complex
Authors: Harata Kazuaki 
Published: July 2006

Abstract
The crystal structure of the α-cyclodextrin-sodium benzenesulfonate complex, which has a channel-type structure, was determined by X-ray analysis. The crystals were orthorhombic with the space group of P21212, cell dimensions of a=21.832(3), b=16.529(2), and c=8.356(1) Å, and Z=2. The structure was determined on the basis of 2894 diffractometer data and refined by the block-diagonal least-squares methods to the final R-value of 0.069. The benzenesulfonate anion is arranged in the channel which is formed by the stack of α-cyclodextrin rings along the c axis. The benzene ring is located in the cavity, while the sulfonato group is hydrogen-bonded to the primary hydroxyl groups of the adjacent α-cyclodextrin molecule. The space outside the channel is filled with water molecules and sodium ions, and the hydrogen-bonding network is formed. The energy of the complex formation was calculated for two possible structures of the 1 : 1 complex in an aqueous solution.
Preparation and Stereochemistry of a New Isomer (Λ-cis-β) of Cobalt(III) Complexes with (3S,8S)-3,8-Dimethyl-1,4,7,10-tetraazadecane
Authors: Saburi Masahiko , Sato Teiji , Yoshikawa Sadao 
Published: July 2006

Abstract
Carbonatocobalt(III) complex of (3S,8S)-3,8-dimethyl-1,4,7,10-tetraazadecane((3S,8S)-dimetrien) was prepared from trans-[CoCl2(3S,8S)-dimetrien)]ClO4 by treating with carbonate or hydrogencarbonate ion. The carbonato complex was assigned to the Λ-cis-β configuration, a novel geometry for the (3S,8S)-dimetrien complexes. The visible absorption, circular dichroism, and proton magnetic resonance data were obtained for the Λ-β and other carbonato complexes. Preparation and assignment of dinitrocobalt(III) complex with (3S,8S)-dimetrien are given. The relative stabilities of the four isomers of (3S,8S)-dimetrien complexes (Λ-cis-α, Λ-cis-β, Δ-cis-β, and trans) are discussed qualitatively.
Studies of the Mixed Amino Acid Complexes of Cobalt(III). IV. Magnetic Circular Dichroism Spectra of the [Co(ox)x(gly)y(en)z] Complexes
Authors: Matsuoka Nobuko , Shimura Yoichi 
Published: July 2006

Abstract
Magnetic circular dichroism (MCD) spectra of a series of sixteen complexes of the [Co(ox)x(gly)y(en)z] type have been measured. The MCD intensity increases with increasing number of the coordinated carboxylato groups. A negative MCD band whose shape is similar to the corresponding absorption band was observed in the first d-d absorption band region. This negative band is assigned to the “B” term, in which the “A” term is swamped. A positive and a negative MCD band appear in the second d-d absorption band region. The origin of the positive band is discussed.
pH-Dependency of Photocyclization of Diarylfumaronitriles
Authors: Ichimura Kunihiro , Watanabe Shoji 
Published: July 2006

Abstract
The photocyclization of diarylfumaronitriles in aqueous ethanol is influenced by pH. The product ratio of 9,10-dihydro-9,10-dicyanophenanthrenes (IV) decreases with decrease in pH. Discussion is given on the acid-catalyzed isomerization of the 4a,4b-dihydrophenanthrenes to IV from results of observation of the colored intermediate.
Studies of Sulfonyl Radicals. II. Relative Reactivities of Addition Reactions of Sulfonyl Free Radicals to Vinyl Monomers
Authors: Takahara Yoshiyuki , Iino Masashi , Matsuda Minoru 
Published: July 2006

Abstract
Addition reactions of various vinyl monomers towards the free methanesulfonyl and arenesulfonyl radicals have been investigated. Relative reactivities of p-methylstyrene (M2) to styrene (M1) towards methane- and para-substituted benzenesulfonyl radicals are hardly affected by the kind of sulfonyl radical, suggesting that an unpaired electron of methanesulfonyl and arenesulfonyl radicals is localized mainly on sulfonyl groups. Relative reactivities obtained with vinyl monomers were correlated to Hammett’s σp values with ρp=−3.6 and also to Alfrey-Price’s e values, indicating that sulfonyl radicals are strongly electrophilic. The highest selectivity of the benzenesulfonyl radical, obtained in the comparison of the selectivity of a number of radicals in addition reactions towards three representative monomers (Table 5), also supports the above conclusion.
The Bromination and the Mercuration of Bis(dimethylglyoximato)(styryl)pyridinecobalts(III), Styryl-type Cobaloximes
Authors: Shinozaki Hiraku , Kubota Minoru , Yagi Osamu , Tada Masaru 
Published: July 2006

Abstract
cis and trans-p-Cyanostyryl(pyridine) cobaloximes (I and II) and cis and trans-p-methoxystyryl(pyridine)cobaloximes (V and VI) were prepared by the reaction of the reduced form of cobaloxime, bis(dimethylglyoximato)(pyridine) cobalt(I), with cis and trans-p-cyanostyryl bromides and with cis and trans-p-methoxystyryl bromides, respectively. The styryl-type cobaloximes thus obtained retained the stereochemistry, cis or trans, of the starting bromides. The bromination of these styryl-type cobaloximes (I, II, V, and VI) and of the cis and trans-styryl(pyridine)cobaloximes (III and IV) in polar or non-polar solvents gave styryl-type bromides with the retention of configuration. The mercuration of these cobaloximes with mercury(II) acetate in DMF gave styryl-type mercurials, again retaining the original configuration.
The Formation and Reaction of Carbonyl Ylide. The Copper Chelate-catalyzed Decomposition of 1-(Diazoacetyl)fluorenone in the Presence of Ethylenic and Acetylenic Compounds
Authors: Ibata Toshikazu , Motoyama Tadayuki , Hamaguchi Masashi 
Published: July 2006

Abstract
1,3-Dipolar cycloadducts were obtained by the copper chelate-catalyzed decomposition of 1-(diazoacetyl)fluorenone in the presence of acetylenic and ethylenic dipolarophiles. The reaction proceeded via intermediate carbonyl ylide (3), which has been generated by the carbene-carbonyl reaction of 2. The cycloaddition of 3 with ethylenic dipolarophiles was determined to proce d stereospecifically.
The Photochemical Sulfenylation of Halides with Organic Disulfides
Authors: Fujisawa Tamotsu , Ohta Hiromichi 
Published: July 2006

Abstract
The reaction of organic disulfides with aryl radicals photochemically generated from aryl halides was investigated. Diaryl sulfides were obtained from diaryl disulfides when the radiation was provided by a low-pressure mercury lamp, while dialkyl disulfides afforded alkyl aryl sulfides whether the radiation source was a low- or a high-pressure mercury lamp.
Rotational Isomerism and Intermolecular Interaction in the Liquid Phase
Authors: Fujiyama Tsunetake , Kakimoto Masao 
Published: July 2006

Abstract
The Raman intensities of some fundamental lines of 1,2-dichloroethane and 1,2-dibromoethane and related molecules with internal rotation axes were observed at various temperatures. The observed relative intensities were corrected for some systematic errors expected in the intensity measurement. The importance of a local-field effect was emphasized. The van’t Hoff plot of the observed intensity ratios of the trans and gauche isomers showed the existence of strong intermolecular interactions in the liquid phase. The intermolecular interaction energy in the liquid phase was theoretically estimated from both the macroscopic and microscopic points of view. The usefulness of a dipole-dipole interaction model was emphasized.
Equilibrium Dialysis Studies of the DNA-Acridine Complexes
Authors: Kubota Yukio , Eguchi Yoshio , Hashimoto Kazumasa , Wakita Masaaki , Honda Yumi , Fujisaki Yasuo 
Published: July 2006

Abstract
The strong binding of acridine dyes with DNA was studied by means of equilibrium dialysis. Ten acridine derivatives were used to elucidate the effect of the dye structure on the nature of strong binding. In the strong binding, up to one dye molecule per 4–6 nucleotides was bound with the change of free energy in 5–9 kcal mol−1. The introduction of bulky groups to the 10 or 3,6-positions of the acridine ring led to a marked decrease in both the association constant and the maximum number of binding sites per DNA phosphate. These findings suggest that, when a dye molecule is intercalated, the dye is located in such a way that the bulky groups attached to the acridine ring produce some steric hindrance to the binding.
Studies of Iron(II) Complexes with Several Schiff Bases: New Examples of 5T2-1A1 Equilibrium
Authors: Maeda Yonezo , Takashima Yoshimasa , Nishida Yuzo 
Published: July 2006

Abstract
Iron complexes with the Schiff bases of quinolinecarbaldehyde and pyridinecarbaldehyde were prepared. Mössbauer spectra and magnetic susceptibilities of the compounds, Fe(pipa)2(NCS)2, Fe(pa)2(NCS)2, Fe(pot)2(NCS)2·1/2CHCl3, Fe(ppt)2(NCS)2, Fe(ppca)2(NCS)2, and Fe(ppa)2(NCS)2 were studied in the temperature range between 298 and 27 K. It was found that these complexes showed an incomplete 5T2-1A1 transition in the solid. The compound Fe(poca)2(NCS)2 also showed a similar phenomenon. The observations of the behavior of the various complexes indicated that the magnetic changeover from spin-paired to spin-free would be closely associated with a modification of the crystal lattice. The FeL′Cl2(L′: the Schiff bases of quinolinecarbaldehyde) were found to have distorted tetrahedral structures.
The Kinetic Study of the Oxidation Reaction of the Tris(2,2′-bipyridine)cobalt(II) Ion and the Ethylenediamine-N,N,N′,N′-tetraacetato cobaltate(II) Ion by the Peroxodisulfate Ion
Authors: Ohashi Kousaburo , Matsuzawa Morito , Hamano Eichi , Yamamoto Katsumi 
Published: July 2006

Abstract
The kinetics of the oxidation of CoII–EDTA and CoII(bpy)32+ by the peroxodisulfate ion (S2O82−) in acidic media have been studied spectrophotometrically; EDTA and bpy represent ethylenediamine-N,N,N′,N′-tetraacetic acid and 2,2′-bipyridine respectively. The stoichiometry of the reactions of CoII–EDTA with the peroxodisulfate ion was 2CoII–EDTA+S2O82−=2CoII(edta)−+2SO42−. The rate for the oxidation of CoII–EDTA by the peroxodisulfate ion is independent of the concentration of CoII–EDTA, but first-order dependent with respect to the peroxodisulfate-ion concentration. The rate law is d[CoII(edta)−]/dt=2k[S2O82−]. The rate-determining step must be the decomposition of S2O82− into 2SO4\ewdot. The first-order rate constant, the activation enthalpy, and the activation entropy are 5.5×10−8 s−1, 24 kcal mol−1, and −12 eu respectively at pH 3.60, 25 °C, and I=0.50 (NaClO4). Two moles of CoII(bpy)32+ are oxidized by one mole of the peroxodisulfate ion. For the oxidation of CoII(bpy)32+, the following reaction path and rate law were proposed:
& Co^II(bpy)_3^2++S_3O_8^2-\oversetk_e\ightleftarrows[Co^II(bpy)_3^2+·S_2O_8^2-]\xrightarrowkCo^II(bpy)_3^3++SO_4^2-+SO_4^\ewdot
& Co^II(bpy)_3^2++SO_4^\ewdot\xrightarrowfastCo^III(bpy)_3^3++SO_4^2-
& \fracd[Co^II(bpy)_3^3+]dt=\left{\frac2k·K_e1+K_e[S_2O_8^2-]\ight}[S_2O_8^2-][Co^II(bpy)_3^3+]_T
At pH 3.60, 25 °C, and I=0.50 (Na2SO4), the rate constant, k, and the equilibrium constant, Ke, are 0.53 s−1 and 5.6 M−1 respectively. The difference in the rate law and mechanism between CoII–EDTA and CoII–(bpy)32+ may come from the difference in charge on the cobalt(II) complexes.
Halogenation and Nitration of Some Mixed Ligand Acetylacetonato cobalt(III) Complexes
Authors: Kuroda Kashiro , Yoshitani Kouzou , Kunigita Kazufumi , Kamiiba Yukiko , Watanabe Kiyokatsu 
Published: July 2006

Abstract
In six kinds of mixed ligand acetylacetonatocobalt(III) complexes ((NH3)4-, (en)2-, α-trien-, β-trien-, fac(N)-i-dtma-, and mer(N)-i-dtma-complexes), the methine hydrogen of the coordinated acetylacetonate ion has been substituted with chlorine, bromine, and iodine, and in five of them excepting the mer(N)-i-dtma complex, it has been substituted with a nitro group. The halogenated and the nitrated complexes were isolated and identified by means of electronic absorption spectra and NMR spectra. The effects of the substitutions on the properties and the characteristics of the substitution reactions are described and discussed.
Equilibria of Complex Formation in Aqueous Solution between Lead(II) and Thallium(I) Ions, and Cyclic and Linear Poly ethers
Authors: Kodama Mutsuo , Kimura Eiichi 
Published: July 2006

Abstract
logK, ΔH and ΔS values were polarographically determined for the interaction in aqueous solution of Pb2+ and Tl+ ions with a cyclic polyether, 1,4,7,10,13,16-hexaoxacyclooctadecane(18-crown-6), and a linear polyether, tetraethylene glycol dimethyl ether (tetraglyme). The stability constant of a 1:1 Pb2+ complex with the macrocyclic ligand is four figures higher than that with the linear ligand. This macrocyclic effect is explained in terms of entropy.
Preparation and Reactions of 4-Alkoxy-2,2-bis(trifluoromethyl)thietanes and 5-Alkoxy-3,3-bis(trifluoromethyl)dithiolanes
Authors: Kitazume Tomoya , Otaka Toru , Takei Ryutaro , Ishikawa Nobuo 
Published: July 2006

Abstract
4-Alkoxy-2,2-bis(trifluoromethyl)thietanes, 3 (R=Me and Et), were prepared by the reactions of 2,2,4,4-tetrakis(trifluoromethyl)-1,-dithietane with alkyl vinyl ethers in a KF–DMF system. A bimolecular condensation product, bis[4,4-bis(trifluoromethyl)thietan-2-yl]ether, 5, was obtained by the treatment of 3 with concentrated sulfuric acid. On the other hand, when treated with sulfur in DMF in the presence of diethylamine, 3 gave 5-alkoxy-3,3-bis(trifluoromethyl)-1,2-dithiolanes, 8, in rather good yields. Several reactions of these thietanes and 1,2-dithiolanes, including those with butyllithium, were examined.
Carbonization of Aromatic Hydrocarbons. II. Carbonization of Modified Pyrene in the Presence of Aluminum Chloride
Authors: Mochida Isao , Fukuda Noriyoshi , Maeda Keiko , Takeshita Kenjiro 
Published: July 2006

Abstract
The carbonization of four hydrogenated and two methylated pyrene derivatives in the presence of aluminum chloride was investigated to elucidate the effects of the slight structural perturbation on the carbonization properties of pyrene. Hexahydropyrene was found to give coke having a needle-like structure via similar carbonization steps as naphthalene followed. In contrast, dihydropyrene formed coke of a mosaic structure for the most part. Although 1-methylpyrene produced coke with a needle-like structure, in part, reductively methylated pyrene was converted to a mosaic structure as was pyrene. In the case of needle-coke formation, the carbonization process of hydrogenated and methylated pyrene followed the steps of appearance, growth and coalescence of anisotropic spheres where the reaction started at a lower temperature and proceeded more moderately compared with the case of pyrene. It is thus indicated that a partially lowered aromaticity of pyrene may favor its carbonization into needle coke.
The Solubilities and Kraft Points of Fatty Acid Soaps of Odd Carbon Numbers
Authors: Ogino Keizo , Ichikawa Yukinori 
Published: July 2006

Abstract
The solubilities of sodium soaps of odd carbon-number fatty acids were measured at various temperatures and the Kraft points of the soaps were determined from the phase diagrams showing the temperature dependence of equilibria among monomers, micelles, and hydrated solid. It was found that the Kraft points were related with the carbon numbers of the fatty acids in a zig-zag curve.
Preparation and Geometrical Isomers of Cobalt(III) Complexes with Tridentate O–S–O Ligand Thiodiacetate or 3,3′-Thiodipropionate
Authors: Kanamori Kan , Sudani Tokiko , Kawai Kiyoyasu 
Published: July 2006

Abstract
cis(S)-fac- and trans(S)-fac-Isomers of bis(thiodiacetato)cobaltate(III), trans(O)-mer-, s-cis(O)-fac- and u-cis(O)-fac-isomers of (thiodiacetato)(diethylenetriamine)cobalt(III) and trans(O)-mer-isomer of (3,3′-thiodipropionato)(diethylenetriamine)cobalt(III) were prepared. Their geometrical configurations were assigned on the basis of their absorption and PMR spectra. The stereochemistry of the Co(III) complex with a tridentate ligand thiodiacetate is similar to that of the Co(III) complex with iminodiacetate.
The Vibrational Spectra and Rotational Isomerism of Chloro(chloromethyl)silanes
Authors: Sera Keiichi , Suehiro Keigo , Hayashi Michiro , Murata Hiromu 
Published: July 2006

Abstract
The infrared spectra of chloro(chloromethyl)methylsilanes ClCH2SiCl3−n(CH3)n (n=0–2) in the liquid and crystalline states and a part of the Raman spectra in the liquid state have been measured. It has become apparent that, for ClCH2SiCl2CH3 and ClCH2SiCl(CH3)2, two rotational isomers coexist in the liquid state, while only one isomer persists in the crystalline state. The fundamental vibrations for these molecules have been assigned, and the normal vibrations have been calculated on the basis of a modified Urey-Bradley force field. The solvent effects and the calculation of the normal vibrations have indicated that the gauche form for ClCH2SiCl2CH3 and the trans form for ClCH2SiCl(CH3)2 persist in the crystalline state. For ClCH2SiCl3, the barrier height, V3(SiCl3), has been estimated to be 4.6 kcal/mol from the torsional force constant.
The Partial Molar Volumes of Normal Alkanols in Aqueous Sodium Dodecyl Sulfate Solutions
Authors: Manabe Masahiro , Shirahama Keishiro , Koda Masaharu 
Published: July 2006

Abstract
The partial molar volumes of normal alkanols (CmH2m+1OH, m=1–10) in aqueous sodium dodecyl sulfate solutions were measured by a dilatometric method at 25 °C. For the alkanols (m=4–8), different constant partial molar volumes appeared below and above the CMC value, whereas no such difference was observed for lower alkanols (m=1–3), and for higher alkanols (m=8–10) the partial molar volumes above the CMC value are nearly identical with their own molar volumes. The partition coefficient of the alkanols between the bulk and micellar phases is estimated on the basis of the volumetric results.
The Dissociative Excitation and Dissociative Ionization of Simple Aliphatic Hydrocarbons by Controlled Electron Impact
Authors: Tsuji Masaharu , Ogawa Teiichiro , Nishimura Yukio , Ishibashi Nobuhiko 
Published: July 2006

Abstract
Photoemissions from the following excited species were observed from simple aliphatic hydrocarbons (CH4, C2H2, C2H4, 1,3-C4H6) under controlled electron-impact excitation (0–400 eV) at wavelengths from 300 to 600 nm: H(Balmer), CH(A–X, B–X, C–X), CH+(A–X, B–A, b–a), C2(C–A, d–a; not from CH4), and C4H2+(A–X; not from CH4). All the excited species except for C4H2+ from C2H2 and C2H4 were confirmed to be primarily produced. The excitation function (0–400 eV) and the appearance potential of H, CH, and CH+ produced from CH4 and C2H2 were measured, and the corresponding processes of the fragmentation near the threshold were determined. The CH4+e→CH+(B)+H2(X)+H(n=1) and C2H2+e→CH+(B)+CH(X) processes were concluded to be responsible for the formation of CH+(B). The formation of ionic species, H+ and CH+, can be considered as the limiting case of the dissociative excitation for producing H and CH. A triplet excitation process may contribute to the formation of CH(A) from C2H2. The observed threshold energies indicated that superexcited states were involved in the formation of excited neutral fragment species.
Dehydroannulenes. I. Synthesis and Properties of 1,5,10,14-Tetramethyl-6,8,15,17-tetrakisdehydro[18]annulene
Authors: Ojima J\={u}ro , Katakami Tsutomu , Nakaminami Gen , Nakagawa Masazumi 
Published: July 2006

Abstract
1,6,10,15-Tetramethyl-7,9,15,17-cyclooctadecatetraene-2,4,11,13-tetrayne-1,6-diol (VII), a 18-membered cyclic glycol, was synthesized by a stepwise reaction sequence starting from 3-methyl-2-penten-4-ynal (III). Treatment of the cyclic glycol (VII) with stannous chloride dihydrate in concentrated hydrochloric acid yielded tetramethyltetrakisdehydro[18]annulene (VIII). Examination of the NMR spectra clearly indicates that the tetrakisdehydro[18]annulene (VIII) containing formal diacetylene and hexapentaene units sustains a strong diamagnetic ring current and has a high conformational stability.
Carbon Monoxide Oxidation over Chromium Sesquioxide. II. Adsorption Behavior of CO and CO2
Authors: Kobayashi Masayoshi , Date Tomoyuki , Kobayashi Haruo 
Published: July 2006

Abstract
The adsorption behavior of carbon monoxide and carbon dioxide on oxidized and reduced surface of α-Cr2O3 catalyst was studied experimentally by the application of a transient response method. From the analysis of response curves obtained for the concentration of effluent gas component and for the electrical conductivity of catalysts, it was shown that neither carbon monoxide nor carbon dioxide can be adsorbed on the oxidized surface, but they are adsorbed on the reduced surface without electron transfer between adsorbates and the catalysts. Adsorption of carbon monoxide is almost reversible, but that of carbon dioxide is both reversible and irreversible. Oxygen markedly accelerates the desorption of both carbon monoxide and carbon dioxide. It is concluded that this can be attributed to the effect of adsorbed oxygen in lowering the degree of coordinative unsaturation of Cr3+ ions.