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A pretreatment procedure consisting of water vapor oxidation followed by H2 reduction has been developed for enhancing the catalytic activity of as-rolled Ni3Al foils for steam reforming of methane. The catalytic activities of the as-rolled Ni3Al foils in the temperature range of 873–1023 K at a steam to carbon ratio of 1.0 were found to be significantly improved by the pretreatment procedure consisting of a water vapor oxidation at 873–923 K for 1 h followed by a H2 reduction at 873 K for 1 h. Surface characterization of the foils before and after the reactions revealed that many fine NiO particles were formed on the surface by the water vapor oxidation at 873–923 K, whereas much less NiO particles were formed by the water vapor oxidation at low temperatures ( 973 K). During the subsequent H2 reduction treatment at 873 K, These NiO particles were reduced to metallic Ni. It is supposed that the enhancement in catalytic activity is attributed to the fine metallic Ni particles formed on the foil surface by the pretreatment procedure.

The catalytic properties of single-phase Ni3Sn powder in the production of hydrogen via the decomposition of methanol were investigated in isothermal tests at 713, 793, and 873 K. The catalytic activity of Ni3Sn significantly increased with time at 793 and 873 K, but not at 713 K, suggesting that Ni3Sn is spontaneously activated at temperatures above 793 K. At these temperatures, Ni3Sn showed high selectivity for H2 and CO production and low selectivity for CH4, CO2, and H2O production, indicating that methanol decomposition was the main reaction, and that side reactions such as methanation and water–gas shift reaction were suppressed. Surface analysis revealed that fine Ni3Sn particles were formed during the reaction, accompanied by a small amount of deposited carbon. The formation of these particles was suggested to be the cause for the spontaneous activation of Ni3Sn.

The catalytic properties of Ni-25 at% Al (Ni25Al) nanoparticles fabricated by arc plasma evaporation toward methanol decomposition were studied at temperatures ranging from 513 to 753 K. The Ni25Al nanoparticles showed much higher activity than gas atomized Ni25Al powders. They showed a high degree of selectivity for methanol decomposition into H 2 and CO. Side reactions such as methanation and water-gas shift reaction were suppressed to a high temperature of 673 K, which is hardly achieved for common Ni catalysts. Detailed characterization of the Ni25Al nanoparticles showed that they were composed of Ni, Ni 3 Al, and Al 2 O 3 phases with Ni and Al oxides on the surface of the Ni and Ni 3 Al phases. The Ni oxides were reduced to Ni phase by a hydrogen reduction prior to methanol decomposition, while the Al oxides remained unchanged. It is supposed that the Ni phase provided the active sites for methanol decomposition, and the Ni 3 Al and Al 2 O 3 phases acted as supports for the Ni phase. Probably the Ni 3 Al and Al 2 O 3 phases provided good resistance to agglomeration of the Ni phase during the reaction, which might contribute to maintain the high catalytic performance of the nanoparticles for methanol decomposition.

The catalytic activity of Ni-Al (Ni25Al) nanoparticles fabricated by thermal plasma evaporation was examined for methanol decomposition and CO oxidation. The nanoparticles exhibited high activity for both reactions. Characterization of the nanoparticles revealed that the fabricated nanoparticles were mainly comprised of Ni and Ni3Al phases. During CO oxidation, the Ni phase was oxidized to NiO, while the Ni3Al phase remained unchanged. The NiO phase is supposed to serve as the active sites for CO oxidation. In contrast, during methanol decomposition, no obvious oxidation was observed for both Ni and Ni3Al phases. The Ni and Ni3Al phases are supposed to contribute to the high activity for methanol decomposition.

The catalytic properties of Ni3Sn and Ni3Sn2 powders were investigated for producing hydrogen from decomposing methanol during 593–953 K. The activities of Ni3Sn and Ni3Sn2 both increased with increasing temperature, but Ni3Sn showed much higher activity than Ni3Sn2. Furthermore, Ni3Sn and Ni3Sn2 both showed a high degree of selectivity for methanol decomposition.

The effect of acid and alkali leaching on catalytic activity of an atomized Ni3Al powder for methanol decomposition was investigated. It was found that a two-step process, an acid leaching followed by an alkali leaching, was most effective for improving the activity. The optimal conditions of acid and alkali leaching were examined. The effect of the acid and alkali leaching was attributed to the formation of fine Ni species and a porous surface structure.

The objective of this study is to investigate the catalytic properties of intermetallic Ni3Fe foil. We fabricated Ni3Fe foil of 30 µm in thickness by a metallurgical process, and examined the catalytic activity of the Ni3Fe foil for methanol decomposition from 513 to 973 K. The Ni3Fe foil showed activity for methanol decomposition above 623 K. The activity increased with the increase of reaction temperature. Surface analysis revealed that a surface structure of fine Ni-Fe particles dispersed on carbon nanofibers was formed on the foil during the reaction. The activity is attributed to the formation of this fine structure.

A two-step pretreatment, oxidation in air followed by reduction in hydrogen, was performed on Ni3Al foils to improve the catalytic activity for methanol decomposition. A two-layer structure, Ni/Al2O3, was formed over the foil surface which was oxidized at 973 K and reduced, whereas a three-layer structure, Ni/NiAl2O4/Al2O3, was formed over the foil surface that was oxidized at 1173 K and reduced. In both cases the outmost Ni layer consisted of polycrystals and continuously covered the underlying oxides. Both pretreated foils exhibited lower onset temperature and enhanced catalytic activity for methanol decomposition into H2 and CO, compared to the untreated foil, and the difference between them was very small. In addition, they exhibited a good stability in catalytic performance at 673 K. The results demonstrate that the oxidation–reduction pretreatment effectively improves the catalytic performance of Ni3Al foil by the formation of an outmost Ni layer on the foil surface.

Selective dissolution of Ni(γ) in a binary Ni(γ)/Ni 3 Al(γ′) two-phase alloy was performed in an aqueous electrolyte including 1 wt.% (NH 4 ) 2 SO 4 and 1 wt.% citric acid to obtain a rough, γ′-terminated surface. The electrochemical potential for the selective dissolution was determined from the polarization curves of the γ and γ′ single-phase alloys. The selective dissolution tests proved that γ was precisely removed above 1.7 V SCE , resulting in the formation of a rough, γ′-terminated surface. Surface analyses revealed that a passive AlO x , which retarded the dissolution, was preferentially formed on γ′, resulting in a successful selective dissolution.

Cold-rolled Ni3Al foils were found to be spontaneously activated up to a high level during methanol decomposition, forming Ni particles on the foil surface. Utilizing this characteristic phenomenon, we pre-activated the Ni3Al foils and subsequently examined the catalytic properties under steam addition to methanol (steam-to-carbon ratio (S/C) = 0–1.0). The pre-activated foils exhibited high catalytic activity for methanol decomposition from the beginning of the reaction under steam addition and sustained the activity during the entire reaction time. Surface analyses revealed that the Ni particles formed by the pre-activation treatment survived after the reaction at all S/Cs, attributing to the high catalytic activity. Ni3Al foils which were spontaneously pre-activated in pure methanol exhibited high catalytic activity for methanol decomposition from the beginning of the reaction under steam addition and sustained the activity during the entire reaction time.

The catalytic activity of oxidation-reduction pre-treated Ni3Al powder for methane steam reforming was examined. The oxidation-reduction pre-treatment consisted of two steps: oxidation in air at various temperatures from 973 to 1373 K, and then followed by reduction in H2 at 873 K. It was found that the oxidation-reduction treatments significantly reduced the onset temperature of activity, i.e., improved the activity of Ni3Al powder at low temperatures. The characterization of Ni3Al surface showed that an outer surface layer of fine NiO particles were formed on the surface of Ni3Al after oxidation. These NiO particles were reduced to metallic Ni by the subsequent reduction treatment, resulting in the high activity for methane steam reforming. These results indicate that the Ni3Al can form highly active surface structure with oxidation-reduction treatment, having excellent heat resistance.

Methanol decomposition tests were carried out for the first time on cold-rolled Ni3(Si,Ti) foils in a temperature range of 513–793 K to investigate their potential catalytic properties for hydrogen production. The catalytic activity was observed at temperatures above 713 K. At 793 K, the catalytic activity changed with the reaction time in three stages: low-activity incubation, rapid spontaneous activation and highactivity state. Surface analysis revealed an intensive formation of fine Ni particles on the foil surfaces after the second stage where rapid spontaneous activation was observed. The formation of the fine Ni particles was considered to be induced by the selective oxidation of Si in Ni3(Si,Ti). The catalytic activity in the second and third stages was due to the fine Ni particles formed by the spontaneous activation.

Methanol decomposition was carried out under steam addition (steam-to-carbon ratio (S/C) = 0–2.0) over cold-rolled Ni 3 Al foils at temperatures ranging from 513 to 793 K. The spontaneous activation was clearly observed at S/C = 0.1 and below, while suppressed at S/C = 0.5 and above. Surface characterization of the spent foils revealed that fine Ni particles were formed at S/C = 0.1 and below due to the selective oxidation/hydroxylation of Al, while further steam addition suppressed it due to the oxidation/hydroxylation of both Al and Ni. The results confirm the spontaneous activation mechanism due to the formation of fine Ni particles which is induced by the selective oxidation/hydroxylation of Al. Reaction analysis revealed that methanol decomposition mainly occurred even under steam addition. It also revealed the effect of steam addition on the minor side reactions, methanation, water-gas shift reaction and carbon deposition.

cis-[Ru(NO)(CH3CN)(pyca)2] and trans-[Ru(NO)(OH)(pyca)2] (pyca = 2-pyridinecarboxylato) were synthesized and characterized by X-ray crystallography. Electrochemical behaviors of cis-[Ru(NO)(CH3CN)(pyca)2] and cis-[Ru(NO)(CH3O)(pyca)2] in acetonitrile were studied. These complexes showed two reduction processes in CH3CN. The controlled potential electrolyses of cis-[Ru(NO)(CH3O)(pyca)2] in a methanol–acetonitrile mixed solution were performed at the potential of the first reduction process. trans-[Ru(NO)(CH3O)(pyca)2] was isolated from the electrolyzed solution and characterized by IR and CV. The cis–trans geometrical change reaction occurred in the electrochemical one-electron reduction of cis-[Ru(NO)(CH3O)(pyca)2].

The catalytic activity of Ni3Al for methane steam reforming was investigated for the first time using its atomized powder. It was found that the activity was significantly enhanced by the combined pretreatment of acid and alkali leaching, while it was quite low for the as-received powder. The high activity was attributed to the formation of fine Ni particles on the porous surface of the powder.

Methanol decomposition was carried out over flat cold-rolled foils of intermetallic compound Ni3Al in a temperature range 513–793 K. The methanol decomposition into H2 and CO was effectively catalyzed at 713–793 K, without any need for coating catalyst layers on the foil surface before reaction. Both catalytic activity and selectivity to H2 and CO production increased with time during the initial period of reaction, indicating that the Ni3Al foils were spontaneously activated under the reaction conditions. Analysis of the catalytic reaction revealed that the methanol decomposition accompanied three minor side reactions: the Boudouard reaction, (reverse) water–gas shift reaction, and methanation. Surface analyses revealed that fine Ni particles dispersed on carbon nanofibers formed on the Ni3Al foils during the reaction at 713–793 K. We attribute the high catalytic performance at 713–793 K to the gradual formation of this nanostructure.

Hydrogen was produced by methanol decomposition over cold-rolled foils of intermetallic compound Ni3Al which is known as an excellent high-temperature structural material. We found high catalytic activity and selectivity for methanol decomposition in flat cold-rolled Ni3Al foils. The catalytic activity was enhanced above 713 K by the spontaneous formation of fine Ni particles dispersed on carbon nanofibers during the reaction, resulting in high catalytic performance. The results demonstrate that the Ni3Al foils can be used both as catalyst precursors and as structural materials of microreactors for hydrogen production.

The catalytic properties of Ni3Al intermetallics were studied for hydrogen production from methanol. It is found that the alkali-leached Ni3Al powders show a high catalytic activity for the methanol decomposition (CH3OH→2H2+CO). The rate of hydrogen production increases rapidly with increasing reaction temperature. Furthermore, the Ni3Al catalysts suppress the formation of methane and water gas shift reaction, i.e. they show higher selectivity for methanol decomposition than nickel catalysts. These results indicate that the Ni3Al catalysts are highly promising as a catalyst for hydrogen production.

Ni3Al has attractive high temperature properties, such as high strength and good oxidation/corrosion resistance, and is possible to be used for high temperature chemical processing and manufacture. Until now, the catalytic properties of Ni3Al were rarely investigated since the leaching of aluminum from Ni3Al is difficult to obtain a porous Raney-Ni compared to NiAl3 and Ni2Al3. In the present work, the catalytic properties of Ni3Al were examined for hydrogen production reactions from methanol. It was found that alkali-leached Ni3Al showed high activity for methanol decomposition (CH3OH→ 2H2+CO). Furthermore, Ni3Al catalysts suppress the formation of methane, i.e. they show higher selectivity for the methanol decomposition reaction than Ni catalyst. These results indicate a possibility for Ni3Al used as a catalyst for hydrogen production reaction.

The reaction of cis-[Ru(NO)(CH(3)CN)(bpy)(2)](3+) (bpy = 2,2'-bipyridine) in H(2)O at room temperature proceeded to afford two new nitrosylruthenium complexes. These complexes have been identified as nitrosylruthenium complexes containing the N-bound methylcarboxyimidato ligand, cis-[Ru(NO)(NH=C(O)CH(3))(bpy)(2)](2+), and methylcarboxyimido acid ligand, cis-[Ru(NO)(NH=C(OH)CH(3))(bpy)(2)](3+), formed by an electrophilic reaction at the nitrile carbon of the acetonitrile coordinated to the ruthenium ion. The X-ray structure analysis on a single crystal obtained from CH(3)CN-H(2)O solution of cis-[Ru(NO)(NH=C(O)CH(3))(bpy)(2)](PF(6))(3) has been performed: C(22)H(20.5)N(6)O(2)P(2.5)F(15)Ru, orthorhombic, Pccn, a = 15.966(1) A, b = 31.839(1) A, c = 11.707(1) A, V = 5950.8(4) A(3), and Z = 8. The structural results revealed that the single crystal consisted of 1:1 mixture of cis-[Ru(NO)(NH=C(O)CH(3))(bpy)(2)](2+) and cis-[Ru(NO)(NH=C(OH)CH(3))(bpy)(2)](3+) and the structural formula of this single crystal was thus [Ru(NO)(NH=C(OH(0.5))CH(3))(bpy)(2)](PF(6))(2.5). The reaction of cis-[Ru(NO)(CH(3)CN)(bpy)(2)](3+) in dry CH(3)OH-CH(3)CN at room temperature afforded a nitrosylruthenium complex containing the methyl methylcarboxyimidate ligand, cis-[Ru(NO)(NH=C(OCH(3))CH(3))(bpy)(2)](3+). The structure has been determined by X-ray structure analysis: C(25)H(29)N(8)O(18)Cl(3)Ru, monoclinic, P2(1)/c, a = 13.129(1) A, b = 17.053(1) A, c = 15.711(1) A, beta = 90.876(5) degrees, V = 3517.3(4) A(3), and Z = 4.

Single-crystal growth of the decagonal Al–Ni–Co quasicrystal has been performed using the floating zone method. Composition of starting polycrystalline rods was selected as Al 72 Ni 12 Co 16 . A large single-quasicrystal of approximately 1 cc was obtained at the growth speed of 0.5 mm/h. High quality of the grown single-quasicrystal was confirmed by the X-ray Laue back-reflection and neutron diffraction methods.

Ni 3 Al is known as promising high-temperature structural materials because of its excellent high temperature strength and corrosion/ oxidation resistance. Recently, we found that Ni 3 Al shows high activity for methanol decomposition (CH 3 OH → 2H 2 + CO), and little effect for steam reforming of methanol (CH 3 OH + H 2 O → 3H 2 + CO 2 ) in the case of feeding methanol and water. In the present study, we examined the catalytic activity of Ni 3 Al powders by feeding pure methanol at a reaction temperature range from 523 to 633 K. It was found that Ni 3 Al shows not only a high activity for the methanol decomposition but also suppresses the methanation. The catalytic properties of Ni 3 Al were compared to that in the case of feeding both methanol and water.

Ruthenium complexes bearing ethylbis(2-pyridylethyl)amine (ebpea), which has flexible -C(2)H(4)- arms between the amine and the pyridyl groups and coordinates to a metal center in facial and meridional modes, have been synthesized and characterized. Three trichloro complexes, fac-[Ru(III)Cl(3)(ebpea)] (fac-[1]), mer-[Ru(III)Cl(3)(ebpea)] (mer-[1]), and mer-[Ru(II)Cl(3){η(2)-N(C(2)H(5))(C(2)H(4)py)═CH-CH(2)py}] (mer-[2]), were synthesized using the Ru blue solution. Formation of mer-[2] proceeded via a C-H activation of the CH(2) group next to the amine nitrogen atom of the ethylene arm. Reduction reactions of fac- and mer-[1] afforded a triacetonitrile complex mer-[Ru(II)(CH(3)CN)(3)(ebpea)](PF(6))(2) (mer-[3](PF(6))(2)). Five nitrosyl complexes fac-[RuX(2)(NO)(ebpea)]PF(6) (X = Cl for fac-[4]PF(6); X = ONO(2) for fac-[5]PF(6)) and mer-[RuXY(NO)(ebpea)]PF(6) (X = Cl, Y = Cl for mer-[4]PF(6); X = Cl, Y = CH(3)O for mer-[6]PF(6); X = Cl, Y = OH for mer-[7]PF(6)) were synthesized and characterized by X-ray crystallography. A reaction of mer-[2] in H(2)O-C(2)H(5)OH at room temperature afforded mer-[1]. Oxidation of C(2)H(5)OH in H(2)O-C(2)H(5)OH and i-C(3)H(7)OH in H(2)O-i-C(3)H(7)OH to acetaldehyde and acetone by mer-[2] under stirring at room temperature occurred with formation of mer-[1]. Alternative C-H activation of the CH(2) group occurred next to the pyridyl group, and formation of a C-N bond between the CH moiety and the nitrosyl ligand afforded a nitroso complex [Ru(II)(N(3))(2){N(O)CH(py)CH(2)N(C(2)H(5))C(2)H(4)py}] ([8]) in reactions of nitrosyl complexes with sodium azide in methanol, and reaction of [8] with hydrochloric acid afforded a corresponding chloronitroso complex [Ru(II)Cl(2){N(O)CH(py)CH(2)N(C(2)H(5))C(2)H(4)py}] ([9]).

Nitrosylruthenium complexes containing 2,2':6',2"-terpyridine (terpy) have been synthesized and characterized. The three alkoxo complexes trans-(NO, OCH3), cis-(Cl, OCH3)-[RuCl(OCH3)(NO)(terpy)]PF6 ([2]PF6), trans-(NO, OC2H5), cis-(Cl, OC2H5)-[RuCl(OC2H5)(NO)(terpy)]PF6 ([3]PF6), and [RuCl(OC3H7)(NO)(terpy)]PF6 ([4]PF6) were synthesized by reactions of trans-(Cl, Cl), cis-(NO, Cl)-[RuCl2(NO)(terpy)]PF6 ([1]PF6) with NaOCH3 in CH3OH, C2H5OH, and C3H7OH, respectively. Reactions of [3]PF6 with an acid such as hydrochloric acid and trifluoromethansulforic acid afford nitrosyl complexes in which the alkoxo ligand is substituted. The geometrical isomer of [1]PF6, trans-(NO, Cl), cis-(Cl, Cl)-[RuCl2(NO)(terpy)]PF6 ([5]PF6), was obtained by the reaction of [3]PF6 in a hydrochloric acid solution. Reaction of [3]PF6 with trifluoromethansulforic acid in CH3CN gave trans-(NO, Cl), cis-(CH3CN, Cl)-[RuCl(CH3CN)(NO)(terpy)]2+ ([6]2+) under refluxing conditions. The structures of [3]PF6, [4]PF6.CH3CN, [5]CF3SO3, and [6](PF6)2 were determined by X-ray crystallograpy.

The stability of catalytic activity and selectivity of Ni3Al for methanol decomposition were studied by life test at 633 K on the alkali-leached powder samples. The characterization of the samples was carried out by X-ray diffraction, inductively coupled plasma (ICP) analysis, SEM observation, and surface area measurement. The life test showed that the alkali-leached Ni3Al exhibits a very stable activity and a high selectivity for methanol decomposition. The surface characterization after reaction suggests that the high selectivity and stable activity may be attributed to the formation of tiny particles and porous structure which increased the surface area significantly during reaction. These results indicate a possibility of Ni3Al as a catalyst for hydrogen production reaction.

The catalytic cracking of various aliphatic sulfides on the silica-alumina catalyst by the use of a pulse reactor was investigated. The cracking reactivity of these sulfides increased in the following order.CH3SCH3