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SOFCs fed with dry H2 and CH4 fuels were examined using 20 wt% Ni/SDC and 0.2 wt% BaO-added 20 wt% Ni/SDC [Ni(BaO)/SDC] anodes. The i–v characteristics of the cells in H2 and CH4 resulted in a higher output produced by CH4 fuel compared to that produced by H2 fuel in both anodes. In both fuels, better anode characteristics were obtained for Ni(BaO)/SDC. Consequently, the anodic performance was in the order of Ni(BaO)/SDC in CH4 > Ni/SDC in CH4 > Ni(BaO)/SDC in H2 > Ni/SDC in H2. A significant carbon deposition was observed in the Ni/SDC anode in CH4, but the carbon deposition observed in Ni(BaO)/SDC was less. From the DC electrical resistance measurement of the anode films, a remarkable decrease in resistance was observed in Ni/SDC due to the carbon deposition after CH4 exposure. The resistance of Ni(BaO)/SDC was higher than that of Ni/SDC and did not change even after CH4 exposure because of the less carbon deposit. The high dispersibility of Ni particles was confirmed in both anodes and was particularly remarkable in Ni(BaO)/SDC. The highest anodic performance in Ni(BaO)/SDC was attributed to the high Ni dispersibility which might promote CH4 decomposition by producing less carbon deposit. It was speculated that the higher cell output in CH4 than that in H2 is due to the locally high concentration of H2 and/or CO gas on the anode surface by the promotion of CH4 decomposition.

The Ag-loaded perovskite-type oxide catalysts (Ag/LaFeO3-CN and Ag/LaFeO3-imp) were prepared using two different methods, and their catalytic activities for carbon combustion were examined. Ag loading was observed to exhibit a positive effect on the catalytic activity of carbon combustion for an Ag/LaFeO3-CN catalyst that was prepared by the calcination of an Ag-loaded heteronuclear metal cyano-complex precursor. However, Ag loading was not observed to be significantly effective in case of Ag/LaFeO3-imp that was prepared by a general impregnation method. Such a noticeable enhancement in the activity of an Ag/LaFeO3-CN catalyst was assumed to originate from both the high dispersion of Ag that was loaded on LaFeO3 and from the formation of reactive oxygen species between metallic Ag species and the perovskite-type oxide.

The catalytic activity of [Fe(terpy)2]2+ complexes supported on the cation exchange resins, ([Fe(terpy)2]2+@resin), was investigated for the oxidation of benzene with H2O2 to yield phenol. The catalytic activity of an [Fe(terpy)2]2+@Nafion catalyst for the oxidation of benzene with H2O2 was observed to be five times more than that in case of the [Fe(terpy)2]2+@resin catalysts. Among the [Fe(terpy)2]2+@resin catalysts that were investigated in this study, the [Fe(terpy)2]2+@Nafion catalyst exhibits the highest durability against H2O2 because the other resins were dissolved or dispersed in the reaction solvent. Nafion was found to be the best candidate among the polymer supports for loading the Fe complex active to perform the oxidation of a substrate with H2O2.

Fe-bipyridine complexes were encapsulated into cation-exchanged Y-type zeolites (M-Na-Y: M = K+, Cs+, Mg2+, Ca2+, NH4+, TMA+, and TBA+) and their catalytic activities for oxidation of benzene with hydrogen peroxide (H2O2) to phenol were investigated in three types of solvents (CH3CN, H2O, and CH3CN + H2O(1:1)). Regardless of the kind of solvent, the counter cation in [Fe(bpy)3]2+@M-Na-Y did not affect the selectivity to phenol. No significant difference in catalytic activity of [Fe(bpy)3]2+@M-Na-Y appeared in CH3CN + H2O (1:1), while a difference on catalytic activity appeared in each CH3CN and H2O solvent. It was suggested that the catalytic activity is related with the accessibility of benzene to [Fe(bpy)3]2+ site in [Fe(bpy)3]2+@M-Na-Y, controlled by the hydrated ionic radius of the counter cation introduced. The effect of ligand coordinated with Fe ion was investigated by comparing the catalytic activities for oxidation of cyclic hydrocarbons (benzene, cyclohexane, and cyclohexene) over [Fe(bpy)3]2+@Na-Y, [Fe(phen)3]2+@Na-Y, and [Fe(terpy)2]2+@Na-Y (phen = 1,10-phenanthroline and terpy = 2,2′;6′,2″-terpyridine). It was suggested that the expansion of π-electron over the ligands such as phen and terpy improves the uptake ability of substrates having π-electron such as benzene.

[Cu(terpy)]2+ complexes encapsulated into Na-Y zeolite ([Cu(terpy)]2+@Y) were prepared, and their catalytic activities for the oxidation of sulfides using hydrogen peroxide were investigated. Several spectroscopic results, as well as elemental analysis, demonstrated the formation of [Cu(terpy)]2+ complexes in supercages of Y-zeolite. [Cu(terpy)]2+@Y exhibited high selectivity for the oxidation of thioanisole into methylphenylsulfoxide when H2O2 was used. The kinetic study of this oxidation at the catalyst [Cu(terpy)]2+@Y suggests that the reaction of [Cu(terpy)]2+ species with H2O2 is the rate-determining step. The oxidation of thioanisole, benzene, and 2-phenylethylamine using [[Cu(terpy)]2+@Y]*, which was prepared from the reaction between [Cu(terpy)]2+@Y and H2O2, quantitatively proceeded to methylphenylsulfoxide, phenol, and 2-amino-1-phenylethanol, respectively. The reaction of [Cu(terpy)]2+@Y and H2O2 was found to yield thermally stable but active CuII-OOH species in [Cu(terpy)]2+@Y.

This study aimed to investigate a cerium triethanolamine complex precursor for the self-propagating high-temperature synthesis (SHS) of highly dispersed ceria-supported noble metal catalysts. The cerium complex precursor (Ce-TEA) was prepared by mixing cerium nitrate and triethanolamine and analyzed its decomposition by the thermogravimetry and differential thermal analysis. It was found that, in air, Ce-TEA undergoes a thermal runaway at approximately 250 °C. This result suggested the possibility of inducing a self-sustained decomposition process at room temperature. In addition, the precursor can easily coordinate with metal noble nitrates in an aqueous solution. As a result, preparation of ceria-supported noble metal catalyst can be achieved by local ignition of the resulting noble metal doped cerium precursor. This novel approach can be used to yield Pd/CeO2 catalyst with various Pd loading in a single step without further annealing. XRD and XPS results of the prepared catalyst suggest that palladium is highly dispersed in its ionic state on the ceria support.

The effect of oxygen diffusion on the thermal decomposition kinetics of La[Fe(CN)6]·5H2O has been explored. In particular, the critical conditions under which LaFeO3 can be synthesized via solid-state combustion of this cyano complex precursor were analytically and numerically investigated. Thermal analysis experiments as well as simulations showed that the oxygen diffusion enhancement facilitates the formation of a self-propagating combustion front during the decomposition of La[Fe(CN)6]·5H2O. As a consequence, the sample undergoes local overheating that raises its temperature by several hundreds of degrees. This enables the production of LaFeO3 perovskite-type oxide with a minimum contribution of external heat resources. Although the self-propagating high-temperature method has already proven to be successful for the synthesis of perovskite-type oxides from cyano complex precursors under oxygen atmosphere, we will show that under the appropriate settings, air can be used instead. Moreover, the temperature of the front is related to the ease of oxygen diffusion. Therefore, the surface area and the crystal size of LaFeO3 perovskite-type powders obtained via solid state combustion have been controlled by controlling the gas flow rate at which the sample has been exposed during the treatment

Treatment of dialkylbenzylsilanes (1) with trityl tetrakis(pentafluorophenyl)borate (TPFPB) afforded the corresponding silylium ions in equilibrium with their intra- or intermolecular π-complexes, which underwent dehydrogenative annulation with various alkenes to form 1,2,3,4-tetrahydro-2-silanaphthalenes (4) in up to 82% isolated yield. Sterically bulkier substituents on the silicon atom tended to increase the yield of cyclic products 4. The annulation products retained the stereochemistry in cases of the reactions using internal alkenes. The use of diisopropyl(1-naphthyl)silane (2) instead of 1 also resulted in annulation to obtain the 2,3-dihydro-1-sila-1H-phenalene derivatives 6. Electrophilic aromatic substitution at the 8-position was predominant, despite the two potentially reactive positions on the naphthyl group. The steric hindrance of the naphthyl group prevented addition of the cis-alkene to the silylium ion, which would considerably decrease yields of the desired products from 2 compared to those from 1.

Samaria-doped ceria (SDC) possesses a higher oxide ionic conductivity compared to YSZ, furthermore it exhibits a high electronic conductivity under a reducing condition. Therefore SDC can form electron conduction paths instead of Ni particles, which means Ni concentration can be suppressed to avoid their aggregation. As a result of suppressing Ni aggregation, the 20wt% Ni/SDC anode exhibited the higher performance compared to that containing lower or higher concentration of Ni. This is due to the increase in the number of reaction site, i.e., interfaces between Ni particles and SDC. Ni-Fe anodes with the high Ni-Fe concentrations have been already reported. Lu et al. evaluated the 50wt% Ni1-xFex/SDC anode in hydrogen fuel and reported their best performance at x=0.25. They assigned the modified performance to the electronic interaction between Ni and Fe. In the present study, we newly prepared Ni-Fe/SDC anode containing 20wt% Ni-Fe alloy, and their anodic properties were investigated by the impedance analyses. The Ni1-xFex/SDC particles were prepared by the impregnation method using the nitrates of the corresponding metals. The precursors were calcinated at 700oC for 10h. The obtained powers were deposited on the dense 10Sc1CeSZ disk and sintered at 900oC. The cathode was formed with Pt paste on the opposite surface of the 10Sc1CeSZ disk. 100%H2 and air were supplied on the anode and cathode, respectively. All the impedance spectra of the Ni1-xFex/SDC anodes were measured at 800oC with the three-terminal configuration under the OCV condition. The impedance spectra of the anodes exhibited an ohmic component and two depressed arcs. Therefore, the spectra were fitted by assuming the equivalent circuit of R ohm(RHFQHF)(R LH Q LF), where Q is a phase constant element. The R HF component hardly influenced by P H2, and on the other hand, the R LF component was proportional to P H2 0.5. From these results, we assigned the R HF and R LF to charge transfer process of hydrogen and surface diffusion of the hydrogen atoms, respectively. Furthermore, the R LF component sensitively decreased by the humidification of hydrogen. Therefore it was found that the adsorbed water molecule or associated species helped hydrogen atom diffuse on the anode. The i-v characteristics of the cells with the Ni1-xFex/SDC anodes were resulted in order of 0.5 ≥ 0.2 > 0.8 ≥ 0. The crystallite sizes of the Ni1-xFex/SDC were dependent on x, and minimum at x=0.5. The i-v characteristics correlated with the crystallite size. The impedance spectra of the Ni1-xFex/SDC anodes were also fitted by assuming the equivalent circuit of R ohm(RHFQHF)(R LH Q LF). The R LF, which can be assigned to the dissociative adsorption and surface diffusion of hydrogen, was most variable among the resistance components. The x=0.5 anode exhibited the R LF minimum value. Therefore we tentatively conclude that Fe addition to Ni reduces the potential for the hydrogen dissociation and the surface diffusion processes.

The perovskite-type oxide catalyst, SmFeO3, prepared by decomposition method of heteronuclear cyano complex precursor (CN method) was applied to liquid-phase organic reaction, cyanosilylation of benzaldehyde with TMSCN. The maximum catalytic activity per catalyst weight was achieved at 800 °C of calcination temperature in CN method and it was found that the catalytic activity was strongly related to the crystallinity of SmFeO3 catalyst. The catalytic reaction performed in the presence of pyridine and 2,6-di-tert-butylpyridine suggests that the catalytically active sites are the Bronsted acid sites formed on the SmFeO3 catalyst. The catalytic activity of SmFeO3 catalyst prepared by CN method was much higher than those of acid catalysts: SiO2–Al2O3 and Amberlyst.

Fe-bipyridine complexes encapsulated into Na-Y ([Fe(bpy)3]2+@Y) were prepared and their catalytic activities for oxidation of cyclohexene with hydrogen peroxide in CH3CN and H2O solvents were investigated. The prepared [Fe(bpy)3]2+@Y was characterized by several methods and it was found that slightly distorted or compressed [Fe(bpy)3]2+ ions were formed within supercages of Y-type zeolite. [Fe(bpy)3]2+@Y catalyst exhibited both higher activity and higher selectivity to 2-cyclohexen-1-ol in water solvent than another Fe catalysts. In addition, the selective hydroxylation of cyclohexene to 2-cyclohexen-1-ol with molecular oxygen was successfully achieved for [Fe(bpy)3]2+@Y catalyst.

A Zn-Sn precursor with cubic-shaped particles was successfully prepared by a simple coprecipitation method to obtain Zn-Sn mixed oxide (ZTO) catalysts. The resulting ZTO catalyst maintained the cubic shape even after calcination at 900 °C. The catalytic activity for the cyanosilylation of benzaldehyde with trimethylsilyl cyanide increased with increasing calcination temperature, and reached the maximum value at 600 °C. The ZTO catalyst calcined at 600 °C exhibited higher catalytic activity than the other solid acid catalysts, SiO2–Al2O3 and Amberlyst 15 DRY.

Ni-impregnated SDC powders were prepared as a SOFC anode material. Surface area of the SDC powders was regulated with pre-calcination temperature and it was ranging from 12 to 93 m 2 /g. The averaged Ni particle size on SDC was fairly affected with surface area of the SDC supports. The smallest Ni particle size obtained in this study was 48 nm when the surface area of SDC was 27 m 2 /g. By further increasing the surface area of SDC to 93 m 2 /g, Ni particle size was adversely enlarged. The maximum power density increased with decreasing the averaged Ni particle size of Ni/SDC anode. The maximum power densities were 39.5 mWcm − 2 for dry H 2 and 106.5 mWcm − 2 for dry CH 4 .

Itaconic acid is a platform compound for bio-based renewable materials. This study employs itaconic anhydride (IAn) as a novel monomer for lipase-catalyzed ring-opening addition condensation polyme ...

The giant cubozoan Morbakka virulenta was collected from the central part of the Seto Inland Sea, west- ern Japan in October 2009, in order to observe its development and polyp formation. Fertilization occurred exter- nally. Demersal fertilized eggs were obtained during the incubation of mature females and males kept at a tempera- ture of ca. 17 to 21°C. From the two-cell stage onwards, fertilized eggs developed into blastulae within 4 h. The development of the blastulae stopped for 21 days after forming blastocysts. This formation of blastocysts is up to now unique within the Cnidaria. The planulae, which developed inside the cysts and lacked larval ocelli, this being characteristic for the Cubozoa, finally metamorphosed into polyps bearing only a single tentacle. The 16-tentacled- stage in polyps was reached about three months after this metamorphosis. Budding occurred in eight-tentacled polyps and swimming polyps were released nine days after the commencement of budding. These unique develop- mental features of M. virulenta may shed additional light on the evolution of life history strategies in the Cnidaria.

Treatment of dialkylbenzylsilanes (1) with trityl tetrakis(pentafluorophenyl)borate (TPFPB) afforded the corresponding silylium ions in equilibrium with their intra- or intermolecular π-complexes, which underwent dehydrogenative annulation with various alkenes to form 1,2,3,4-tetrahydro-2-silanaphthalenes (4) in up to 82% isolated yield. Sterically bulkier substituents on the silicon atom tended to increase the yield of cyclic products 4. The annulation products retained the stereochemistry in cases of the reactions using internal alkenes. The use of diisopropyl(1-naphthyl)silane (2) instead of 1 also resulted in annulation to obtain the 2,3-dihydro-1-sila-1H-phenalene derivatives 6. Electrophilic aromatic substitution at the 8-position was predominant, despite the two potentially reactive positions on the naphthyl group. The steric hindrance of the naphthyl group prevented addition of the cis-alkene to the silylium ion, which would considerably decrease yields of the desired products from 2 compared to t...

For developing broader application of biobased polymers, graft copolymers and comb polymers having poly(lactic acid) (PLA) side chains have been synthesized by using a macromonomer technique. PLA macromonomers (MMm) having a methacryloyl polymerizable group with different PLA chain length with an average length m = 4, 6, 8, 12, 18, and 30 were prepared via ring-opening polymerization of l-lactide using hydroxyethyl methacrylate (HEMA) initiator catalyzed by Sn(Oct)(2). Radical polymerization behaviors of these macromonomers were examined. Radical copolymerization of MMm (m = 4, 6, and 8), with vinyl monomers like n-butyl methacrylate (BMA) and n-butyl acrylate (BA) in water as the reaction medium, gave stable miniemulsions of poly[n-butyl (meth)acrylate-graft-lactic acid]s [PB(M)A-g-PLAm]. MMm with m value higher than 12, however, gave aggregate products in a minor amount besides miniemulsions in a major amount, producing not a stable emulsion system of graft copolymers. The solution copolymerization, on the other hand, produced a wider variety of the graft copolymers, where a wider range of MMm (even m ≥ 12) can be employed. In a 1,4-dioxane solution, the radical copolymerization of MMm with BMA and methyl methacrylate (MMA) gave various graft copolymers [PB(M)MA-g-PLAm]. A new type of comb polymers (PMMm) having PLAm as pendant side chains were obtained by radical homopolymerization of MMm in a 1,4-dioxane solution. The graft copolymers and comb polymers obtained here are amorphous. Physical properties of the polymers from miniemulsions suggested them to be applicable for coatings or elastic materials which are environmentally desirable as a new class of biobased polymers. In addition, the present approach provided fundamental information on relationships between the length of PLA side chain and the bulk properties of the product polymers.

The influence of A-site lanthanoids in the perovskite-type oxide catalysts, LnFexCo1−xO3 (Ln = La, Pr, Sm, Gd, Dy, Ho, Er, and Yb), prepared by the thermal decomposition of cyano complexes, Ln[FexCo1−x(CN)6]·nH2O, on the catalytic activity of CO oxidation was investigated. Using XRD, N2 adsorption, SEM, XPS, and H2-temperature programmed reduction (TPR) techniques, it was found that A-site lanthanoid ions in perovskite-type oxide LnFeO3 affect the formation temperature of single phase, the crystalline structure, and the size of perovskite-type oxide particles. The catalytic activity of LnCoO3 was improved by the replacement of Co ion with Fe ion regardless of the kind of A-site lanthanoid ion. A-site lanthanoids in perovskite-type oxide also affect the reducibility of B-site Co ion in LnFe0.5Co0.5O3, leading to the change in the catalytic property. TPR results of LnFe0.5Co0.5O3 suggest that the reducibility of Co ion is related to the distortion of perovskite structure.

The thermal decomposition reaction of crystalline heteronuclear cyano complex precursor to crystalline perovskite-type oxide catalyst was investigated. From X-ray single crystal analysis and XRD, FT-IR, TG-DTA, SEM, and BET measurements, the thermal decomposition process of Sm[Fe(CN)6]·4H2O precursor was elucidated. It was found that the specific surface area of SmFeO3 decreased monotonously with increasing calcination temperature of Sm[Fe(CN)6]·4H2O, while the highest catalytic activity for CO oxidation was achieved for Sm[Fe(CN)6]·4H2O calcined at 600 °C. The size of Sm[Fe(CN)6]·4H2O precursor depended on the molar concentration of starting materials, Sm(NO3)3·6H2O and K3Fe(CN)6, in aqueous solution (Cs); the size of Sm[Fe(CN)6]·4H2O decreased with decreasing Cs. The decrease in particle size of cyano complex was found to result in the increase in specific surface area of perovksite-type oxide obtained after calcination.

The carbon oxidation over copper ion-exchanged zeolites (Cu-MFI, Cu-MOR, Cu-FAU, and Cu-BEA) pretreated at 700 °C was investigated. The catalytic activities of Cu-MFI, Cu-MOR, and Cu-FAU pretreated at 700 °C were higher for carbon oxidation in NO + O2 atmosphere than that of Cu-BEA. The TEM results demonstrated that Cu fine particles were formed on the external surface of Cu-MFI, Cu-MOR, and Cu-FAU, showing high activity. In addition, it was suggested that the coexisting NO plays an important role in enhancing the catalytic activity of Cu-MFI for carbon oxidation.

多系統萎縮症とは以前よりオリーブ橋小脳萎縮症（OPCA），線状体黒質変性症（SND），Shy-Drager（SDS）と呼ばれてきた3疾患を包括した病理学的疾患概念の総称である。今回我々は本疾患患者に対し，八味地黄丸を投与したところ，起立時の血圧変動に著明な改善を認めた症例を経験したので報告する。症例は79歳男性。緩徐進行性に動作緩慢，すくみ足，手指振戦を認め，その後立ちくらみ症状が出現。起立性低血圧が見られ各種薬剤の投与を行うが効果は不十分であった。このため八味地黄丸を追加投与したところ，体位変換時の血圧変動が小さくなり，さらに諸症状の改善も認めた。八味地黄丸は自律神経機能の改善に効果を示す方剤とされており，本症例においても多系統萎縮症に伴う起立性低血圧の改善に寄与したと考えられた。

The photocatalytic reaction in the partial oxidation of α-methylstyrene (α-MS) to acetophenone (AP) was investigated for TiO 2 supported on H-ZSM-5 (H-MFI), H-mordenite (H-MOR), and H-Y-type (H-FAU) zeolites. XRD results demonstrated that the anatase was the stable phase of TiO 2 supported on zeolites. Photocatalytic activities of supported catalysts decreased in the following order: TiO 2 /H-MFI >> TiO 2 /H-MOR > (TiO 2 ) > TiO 2 /H-FAU >> (blank). TiO 2 /H-MFI catalyst exhibited the best performance for photocatalytic oxidation of α-MS to AP. The maximal activity was obtained by 25 wt% TiO 2 /H-ZSM-5. The addition of water to the reaction solvent resulted in significantly lowering the photocatalytic activity for TiO 2 /H-ZSM-5 catalyst, although its activity for TiO 2 and TiO 2 + H-ZSM-5 mechanical mixture was little influenced by the amount of water added to reaction solvent.

Among diabetes mellitus type 2 (DM2) patients, the frequency of cognitive dysfunction is higher and the relative risk of Alzheimer’s disease (AD) is approximately twice that of nondiabetics. Cognitive impairment symptoms of AD are induced by limbic system dysfunction, and an early-stage AD brain without dementia has the potential for atrophy in the hippocampal region. In this study, we estimated potential hippocampal region atrophy in DM2 and pursued the association between DM2 and cognitive impairment/AD. Voxel-based morphometry analysis was performed in 28 diabetics (14 men, 14 women; ages 59–79 years, mean 70.7 years) and 28 sex- and agematched (±1 year) nondiabetics. Severity of gray matter loss in the hippocampal region and whole brain were investigated. Group analysis was performed using twotailed unpaired t-test; significance was assumed with less than 1% (P < 0.01) of the critical rate. There was a significant difference between diabetics and nondiabetics regarding the severity of hippocampal region atrophy and whole-brain atrophy. Only diabetics showed a positive correlation for severity of hippocampal region atrophy and whole-brain atrophy (rs = 0.69, P < 0.0001). Aged DM2 patients have the potential for hippocampal region atrophy, and its dysfunction can be related to the expression of a cognitive impairment that resembles AD.

Pt catalysts supported on Al2O3 beads prepared by a sputter deposition method showed the higher surface concentration of Pt than impregnated Pt catalysts. The catalytic activities of the oxidation of acetylene carbon black over the sputtered Pt catalysts were higher than those over the impregnated Pt catalysts with the same Pt content.

The carbon oxidation was investigated over copper ion-exchanged MFI zeolite (Cu-MFI) as a function of pretreatment temperature. Cu-MFI pretreated at 700 °C exhibited high activity for carbon oxidation in NO + O2 atmosphere. The activity of Cu-MFI pretreated at 700 °C increased with increasing the amount of copper ion exchanged. XRD and ESR measurements suggest that the CuO fine particles as an active site for carbon oxidation were formed on the surface of MFI zeolite by pretreatment at 700 °C.

A novel dialuminum-substituted silicotungstate TBA(3)H[gamma-SiW(10)O(36){Al(OH(2))}(2)(mu-OH)(2)] x 4 H(2)O (1, TBA = tetra-n-butylammonium) was synthesized by the reaction of the potassium salt of [gamma-SiW(10)O(36)](8-) (SiW10) with 2 equiv of Al(NO(3))(3) in an acidic aqueous medium. It was confirmed by the X-ray crystallographic analysis that compound 1 was a monomer of the gamma-Keggin dialuminum-substituted silicotungstate with the {Al(2)(mu-OH)(2)} diamond core. The cluster framework of 1 maintained the gamma-Keggin structure in the solution states. The reaction of 1 with pyridine yielded TBA(3)[(C(5)H(5)N)H][gamma-SiW(10)O(36){Al(C(5)H(5)N)}(2)(mu-OH)(2)] x 2 H(2)O (2), and the molecular structure was successfully determined by the X-ray crystallographic analysis. In compound 2, two of three pyridine molecules coordinated to the axial positions of aluminum centers and one of them existed as a pyridinium cation, showing that compound 1 has two Lewis acid sites and one Brønsted acid site. Compound 1 showed high catalytic activity for the intramolecular cyclization of citronellal derivatives such as (+)-citronellal (3) and 3-methylcitronellal (4) without formation of byproduct resulting from etherification and dehydration. For the 1-catalyzed cyclization of 3, the diastereoselectivity toward (-)-isopulegol (3a) reached ca. 90% and the value was the highest level among those with reported systems so far. The reaction rate for the 1-catalyzed cyclization of 3 decreased by the addition of pyridine, and the cyclization hardly proceeded in the presence of 2 equiv of pyridine with respect to 1. On the other hand, the reaction rate and diastereoselectivity to 3a in the presence of 2,6-lutidine were almost the same as those in the absence. Therefore, the present cyclization is mainly promoted by the Lewis acid sites (aluminum centers) in 1. DFT calculations showed that the formation of the transition state to produce 3a is sterically and electronically more favorable than the other three transition states for the present 1-catalyzed cyclization of 3.

Hydrogen atom abstraction reactions have been implicated in oxygenation reactions catalyzed by copper monooxygenases such as peptidylglycine alpha-hydroxylating monooxygenase (PHM) and dopamine beta-monooxygenase (DbetaM). We have investigated mononuclear copper(I) and copper(II) complexes with bis[(6-neopentylamino-2-pyridyl)methyl][(2-pyridyl)methyl]amine (BNPA) as functional models for these enzymes. The reaction of [Cu(II)(bnpa)]2+ with H2O2, affords a quasi-stable mononuclear copper(II)-hydroperoxo complex, [Cu(II)(bnpa)(OOH)]+ (4) which is stabilized by hydrophobic interactions and hydrogen bonds in the vicinity of the copper(II) ion. On the other hand, the reaction of [Cu(I)(bnpa)]+ (1) with O2 generates a trans-mu-1,2-peroxo dicopper(II) complex [Cu(II)2(bnpa)2(O2(2-]2+ (2). Interestingly, the same reactions carried out in the presence of exogenous substrates such as TEMPO-H, produce a mononuclear copper(II)-hydroperoxo complex 4. Under these conditions, the H-atom abstraction reaction proceeds via the mononuclear copper(II)-superoxo intermediate [Cu(II)(bnpa)(O2-)]+ (3), as confirmed from indirect observations using a spin trap reagent. Reactions with several substrates having different bond dissociation energies (BDE) indicate that, under our experimental conditions the H-atom abstraction reaction proceeds for substrates with a weak X-H bond (BDE72.6 kcal mol(-1)). These investigations indicate that the copper(II)-hydroperoxo complex is a useful tool for elucidation of H-atom abstraction reaction mechanisms for exogenous substrates. The useful functionality of the complex has been achieved via careful control of experimental conditions and the choice of appropriate ligands for the complex.

In order to gain an understanding of the role of the sulfenyl group of nitrile hydratase (NHase), a new Co(III) complex with a sulfenyl-type ligand (LC=O:N2(SO)2), Na[CoIII(LC=O:N2(SO)2)(tBuNC)2] (2), was synthesized. The compound includes two amide groups, two sulfenate sulfurs in the equatorial plane, and two tBuNC molecules in the axial positions. Characterization of the compound was performed by UV-vis spectroscopic, IR spectral, thermogravimetric (TG), and X-ray structure analytical methods. The results are discussed in the context of Co(III) complexes containing the corresponding sulfur-type (LC=O:N2S2) (1) and sulfinyl-type ligands (LC=O:N2(SO2)2) (3). Complex 2 crystallized with the formula Na[CoIII(LC=O:N2(SO)2)(tBuNC)2].urea.2H2O.0.5EtOH. The X-ray structure revealed that the Co(III) complex has an octahedral geometry with Co-S=av. 2.221 A, Co-N=av. 1.998 A, and Co-C=av. 1.87 A. The sulfenyl oxygen and amidate carbonyl oxygen are linked to urea, water, EtOH, and Na+ and participate in a hydrogen-bond and an electrostatic interaction. IR and TG measurements demonstrated that the coordination strength of tBuNC to the Co atom increases as follows: 1

A novel (μ 3 -oxo)tetraruthenium cluster ( 2 ) was synthesized in an isolated yield of 73% by the reaction of a zerovalent ruthenium complex, Ru(η 6 -cot)(η 2 -dmfm) 2 ( 1 ) [cot = 1,3,5-cyclooctatriene, dmfm = dimethyl fumarate], with water under reflux in 1,4-dioxane for 6 h. The structure and the X-ray characterization of this novel complex 2 as well as a possible formation mechanism of 2 are disclosed.

The decomposition of La[Fe(CN)6]·5H2O and La[Co(CN)6]·5H2O under different atmospheres has been analyzed by thermogravimetry (TG) and differential thermal analysis (DTA). In addition, the decomposition temperature at different sample locations was monitored for sample masses around 2 g of La[Fe(CN)6]·5H2O and La[Co(CN)6]·5H2O, when they were calcined for 1 h at temperatures ranging from 200 to 400 °C in a controlled gas-flow system. Results showed that, the large enough of the cyano complex precursors undergo combustion when they are decomposed under oxygen atmosphere. X-ray diffraction results revealed that perovskite-type oxides crystallize due to the overheating of the process. As a result, it has been possible to produce LaFeO3 and LaCoO3 perovskite-type oxide powders by SHS under oxygen atmosphere using La[Fe(CN)6]·5H2O and La[Co(CN)6]·5H2O as a precursor. The effect of the ignition temperature has been investigated. The specific surface area of the perovskite-type oxides produced via SHS using heteronuclearcyano metal complex as a precursor is significantly higher than that of other LaMO3 produced using the same technique but obtained from other type of precursors.

In an attempt to understand the unique active site structure of nitrile hydratase, four Co III complexes with square-planar N 2 S 2 - or N 2 (SO 2 ) 2 -type donor sets, Na[Co III (L:N 2 S 2 )] (1-Na), PPh 4 [Co III (L:N 2 S 2 )] (1-PPh 4 ), PPh4[Co III (L:N 2 S 2 )(tBuNC) 2 ] (2), and PPh 4 [Co III {L:N 2 (SO 2 ) 2 }(tBuNC) 2 ] (3) were synthesized and characterized on the basis of electronic absorption spectroscopy, IR spectroscopy, cyclic voltammetry, and X-ray structural analysis. Both of the crystal structures of complexes 1-Na and 1-PPh 4 revealed a square planar structure with N 2 S 2 donating atoms, and 2 exhibited an octahedral structure coordinated with two tert-butylisocyanide (tBuNC) molecules at the axial sites of complex 1-PPh 4 . Complex 3, which showed an octahedral structure with sulfinate sulfur atoms equatorially coordinated to the center, was synthesized by the treatment of 2 with a suitable oxidant. The reduction potential values from Co III to Co II for complex 3 in solution demonstrated a larger positive shift when compared with those of complexes 1-PPh 4 and 2, which indicates that the oxygenation of the sulfur atoms increased the Lewis acidity of the Co III center. Interestingly, the coordination equilibrium, the C=O stretching frequency, and the redox potential for 1-PPh 4 were all closely related to the acceptor number (AN) of the solvents. Furthermore, the coordination of monodentate tBuNC to the axial position of 1-PPh 4 was dependent on the solvents used. These findings indicate that an electrophilic interaction between the carbonyl oxygen atoms and the solvent molecules control the Lewis acidity of the metal ion. On the other hand, such a solvent dependence was not detected in the S=O stretching frequency of sulfinates 3. We have concluded that the increase in the redox potential/ Lewis acidity of the metal center is a result of the oxygenation of sulfur, and that this increase is controlled by the interaction of the amidate carbonyl oxygen with the secondary coordination sphere. As demonstrated in previous mutation studies, this study suggests that the interaction of the nitrile hydratase active site with the functional groups from the peptide backbone is essential for the catalytic activity of the complex.

A disodium tetrakis(phthalimide) palladium(II) complex, [Na2Pd(phthal)4] (1), was synthesized by reaction of four phthalimide molecules with Pd(OAc)2 in the presence of Et3N. The above and below axial sites of the Pd coordination plane formed the spaces suitable for capturing Na+ ions, which were coordinated with the four imidato oxygen atoms. The complex 1 was linked through the Na+ ions bridged by the water molecules, building an infinite chain structure along the crystallographic a axis. The four phthalimidato moieties contacted in the four orthogonal directions together through their π-π stacking interaction. Such a self-assembly of molecule 1 constructed nanopores with a pore size of ca. 3 × 4 Å in the crystals.

Enantiopure organoruthenium aqua complexes, Ru(dppe)(dmfm)2(H2O) (1) [dmfm = dimethyl fumarate] and Ru(QUINAP)(dmfm)2(H2O) (2) [QUINAP = 1-(2-diphenylphosphino-1-naphthyl)isoquinoline], were prepared and the absolute structures were determined by X-ray crystallography. In the crystals of these complexes, the water molecule is captured in the chiral coordination environment assisted by two different hydrogen bonds; that is, a chiral center is generated on the coordinated oxygen of water. The behavior of the coordinated water in 1 and 2 was monitored by variable-temperature 1H NMR measurement. At lower than −60 to −70 °C, the nonequivalency of the geminal protons in the coordinated water molecule was observed even in solution. On the basis of the VT NMR data and DFT study, the behavior of the coordinated water was discussed. Complex 1 reacts with ammonia to give Ru(dppe)(dmfm)2(NH3) (4), which is the first example of the isolated mononuclear Ru(0) ammonia complex. Complex 4 was reversibly converted into 1 ...

In order to understand the effect of an oxygen-containing ligand on the physico-chemical properties and reactivities of hydrogenperoxocopper complexes, new copper(II) complexes with the N3O-type tr...

Ruthenium(II/III) complexes with tripodal tris(pyridylmethyl)amine ligands bearing one, two, or three pivalamide groups (MPPA, BPPA, TPPA: amide-series ligands) or neopentylamine ones (MNPA, BNPA, TNPA: amine-series ligands) at the 6-position of the pyridine ring have been synthesized and structurally characterized. The X-ray structure analyses of the single crystals of these complexes reveal that they complete an octahedral geometry with the tripodal ligand and some monodentate ligands. The amide-series ligands prefer to form a Ru(II) complex, while the amine-series ones give a Ru(III) complex. In the presence of PhIO oxidant, the catalytic activities for epoxidation of olefins, hydroxylation of alkane, and dehydrogenation of alcohol have been investigated using the six ruthenium complexes [Ru(II)(tppa)Cl(2)] (1), [Ru(III)(tnpa)Cl(2)]PF(6) (2), [Ru(II)(bppa)Cl]PF(6) (3), [Ru(III)(bnpa)Cl(2)]PF(6) (4), [Ru(II)(mppa)Cl]PF(6) (5), and [Ru(III)(mnpa)Cl(2)]PF(6) (6). Among them, the amide-series complexes, 1, 3, and 5, showed a higher epoxidation activity in comparison with the amine-series ones, 2, 4, and 6. On the other hand, the latter showed a higher reactivity for hydroxylation, allylic oxidation, and C=C bond cleavage reactions compared with the former. Such a complementary reactivity is interpreted by the character of the ruthenium-oxo species involving electronically equivalent formulas, Ru(V)=O and Ru(IV)-O.

A series of the copper(II) complexes with tripodal tetradentate tris(pyridyl 2-methyl)amine-based ligands possessing the hydrogen-bonding 6-aminopyridine units (tapa, three amino groups; bapa, two amino groups; mapa, one amino group) have been synthesized, and their copper(II) complexes with a small molecule such as dioxygen and azide have been studied spectroscopically and structurally. The reaction of their Cu(II) complexes with NaN(3) have given the mononuclear copper complexes with azide in an end-on mode, [Cu(tapa)(N(3))]ClO(4) (1a), [Cu(bapa)(N(3))]ClO(4) (2a), [Cu(mapa)(N(3))]ClO(4) (3a), and [Cu(tpa)(N(3))]ClO(4) (4a) (tpa, no amino group). The crystal structures have revealed that the coordination geometries around the metal centers are almost a trigonal-bipyramidal rather than a square-planar except for 1a with an intermediate between them. The UV-vis and ESR spectral data indicate that the increase of NH(2) groups of ligands causes the structural change from trigonal-bipyramidal to square-pyramidal geometry, which is regulated by a combination of steric repulsion and hydrogen bond. The steric repulsion of amino groups with the azide nitrogen gives rise to elongation of the Cu-N(py) bonds, which leads to the positive shift of the redox potentials of the complexes. The hydrogen bonds between the coordinated azide and amino nitrogens (2.84-3.05 A) contribute clearly to the fixation of azide. The Cu(I) complexes with bapa and mapa ligands have been obtained as a precipitate, although that with tapa was not isolated. The reactions of the Cu(I) complexes with dioxygen in MeOH at -75 degrees C have given the trans-micro-1,2 peroxo dinuclear Cu(II) complexes formulated as [((tapa)Cu)(2)(O(2))](2+) (1c), [((bapa)Cu)(2)(O(2))](2+) (2c), and [((mapa)Cu)(2)(O(2))](2+) (3c), whose characterizations were confirmed by UV-vis, ESR, and resonance Raman spectroscopies. UV-vis spectra of 1c, 2c, and 3c exhibited intense bands assignable to pi(O(2)(2)(-))-to-d(Cu) charge transfer (CT) transitions at lambda(max)/nm (epsilon/M(-1)cm(-1)) = 449 (4620), 474 (6860), and 500 (9680), respectively. The series of the peroxo adducts generated was ESR silent. The resonance Raman spectra exhibited the enhanced features assignable to two stretching vibrations nu((16)O-(16)O/(18)O-(18)O)/cm(-1) and nu(Cu-(16)O/Cu-(18)O)/cm(-1) at 853/807 (1c), 858/812 (2c), 847/800 (3c), and at 547/522 (2c), 544/518 (3c), respectively. The thermal stability of the peroxo-copper species has increased with increase in the number of the hydrogen-bonding interactions between the peroxide and amino groups.

In order to clarify the effect of hydrogen bonding on the stabilities of (μ-peroxo)dicopper complexes with a trans-μ-1,2-peroxo form, novel copper complexes with intramolecular hydrogen bonding interaction sites have been synthesized, and their spectroscopic properties and thermal stabilities studied. The selected tripodal tetradentate ligands were tris(2-pyridylmethyl)amine (TPA) derivatives bearing pivalamido and amino groups at the 6-position of the pyridine ring in TPA, {[6-(pivalamido)pyrid-2-yl]methyl}bis(pyrid-2-ylmethyl)amine (MPPA) and [(6-aminopyrid-2-yl)methyl]bis(pyrid-2-ylmethyl)amine (MAPA). The single-crystal X-ray structure of a monomeric CuII complex with N3− namely [Cu(mppa)N3]ClO4 (1a), revealed an interligand hydrogen bonding interaction between the substituent NH group of MPPA and the azide nitrogen atom in the axial position. The CuI complexes of MPPA and MAPA were immediately oxygenated with dioxygen in acetone solution at −78 °C to give the μ-peroxo dinuclear copper(II) complexes [{Cu(mppa)}2(O2)]2+ (1b) and [{Cu(mapa)}2(O2)]2+ (2b). These complexes exhibited two kinds of characteristic absorption bands (π*σ⇄dσ, π*v⇄dσ) originating from the ligand−metal charge transfer (LMCT) of O22− to Cu. Affected by the hydrogen bonding interaction, the π*σ⇄dσ CT band shifted significantly to a higher energy region and the π*v⇄dσ CT absorbance decreased due to stabilization of the π*σ orbital and restriction of the Cu−O bond rotation. The thermal stabilities of the (μ-peroxo)dicopper(II) complexes were estimated from their decomposition rates which decreased in the order, 2b ≈ [{Cu(tpa)}2(O2)]2+ (3b) > 1b >> [{Cu(6-metpa)}2(O2)]2+ (4b) {6-MeTPA = [(6-methylpyrid-2-yl)methyl]bis(pyrid-2-ylmethyl)amine}. The above findings indicate that the interligand hydrogen bonding interaction, although overcome to some extent by the adverse effect of the steric bulk of the NH group, is inclined to stabilize (μ-peroxo)dicopper(II) complexes. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

The selective hydroxylation of cyclohexene to 2-cyclohexen-1-ol with hydrogen peroxide in water was successfully achieved using [Fe(bpy)3]2+ complexes encapsulated into Y-type zeolite.

Structural strengths of the piping and components in NPPs have been designed with seismic margin. They are classified seismically S, B and C class in terms of the influence rate to nuclear safety. For the highest seismic class (Class S) equipment, it is clarified that they have enough seismic margins against design seismic conditions by shaking table tests or numerical simulations. However, for the lower seismic class (Class B and C) equipment, their seismic margins have not been clarified quantitatively. In this paper, in order to evaluate seismic robustness of the lower seismic class equipment with no clarification of seismic margin, seismic influences of the lower seismic class equipment in NPPs damaged by actual large earthquakes have been surveyed and sorted as a database, and the integrity of the lower class equipment have been discussed. Seismic effects on 24 plants damaged by the recent large 6-earthquakes are surveyed, sorted as a database, and investigated. As a result, a total of 29 cases of function deterioration or loss were observed. Considering the total number of components and piping, the frequency of those cases in class B and C components and piping was low. And also, as it is found there are a few cases of degradation or loss of function in the equipment installed on the bedrock or in the buildings.

Both Ni and alkaline earth metal oxide (MO: CaO, SrO, and BaO)-impregnated SDC powders were prepared as an SOFC anode material. The averaged Ni particle size on SDC was affected by the kind of alkaline earth metal oxide added. The addition of SrO and BaO to Ni/SDC anode enhanced power densities of both H2-SOFC and CH4-SOFC and the addition of CaO lowered them. The maximum power density increased with decreasing the averaged Ni particle size of Ni-MO/SDC anode.