Browsing by Subject "Nickel"

Article

Coordination Complexes of a Neutral 1,2,4-Benzotriazinyl Radical Ligand: Synthesis, Molecular and Electronic Structures, and Magnetic Properties

Morgan, I. S.; Mansikkamäki, Akseli; Zissimou, Georgia A.; Koutentis, Panayiotis Andreas; Rouzières, M.; Tuononen, H. M.; Clérac, R. (2015)

A series of d-block metal complexes of the recently reported coordinating neutral radical ligand 1-phenyl-3-(pyrid-2-yl)-1,4-dihydro-1,2,4-benzotriazin-4-yl (1) was synthesized. The investigated systems contain the ...

Article

Dry reforming of methane over 5 wt% Ni/Ce1-xPrxO2-δ catalysts: Performance and characterisation of active and inactive carbon by transient isotopic techniques

Vasiliades, Michalis A.; Makri, M. M.; Djinović, P.; Erjavec, B.; Pintar, A.; Efstathiou, Angelos M. (2016)

The effects of Ce1-xPrxO2-δ support composition (x = 0.0–0.8) and reaction temperature (550–750 °C) on the catalytic activity and selectivity and important features of the mechanism of the dry reforming of methane (DRM) ...

Article

Effect of support composition on the origin and reactivity of carbon formed during dry reforming of methane over 5 wt% Ni/Ce1-xMxO2-δ (M = Zr4+, Pr3+) catalysts

Makri, M. M.; Vasiliades, Michalis A.; Petallidou, Klito C.; Efstathiou, Angelos M. (2016)

Carbon dioxide reforming of methane to synthesis gas in the 550-750°C range over 5 wt% Ni/Ce1-xMxO2-δ (M = Zr4+, Pr3+) solids has been investigated with respect to the effects of support chemical composition and reaction ...

Article

Electrically tunable spin injector free from the impedance mismatch problem

Ando, K.; Takahashi, S.; Ieda, J.; Kurebayashi, H.; Trypiniotis, Theodossis; Barnes, C. H. W.; Maekawa, S.; Saitoh, E. (2011)

Injection of spin currents into solids is crucial for exploring spin physics and spintronics. There has been significant progress in recent years in spin injection into high-resistivity materials, for example, semiconductors ...

Article

Exothermic reaction characteristics of continuously ball-milled Al/Ni powder compacts

Hadjiafxenti, A.; Gunduz, I. E.; Kyratsi, Theodora; Doumanidis, C. C.; Rebholz, Claus (2013)

Self-propagating reactions in compacted pellets of continuously low-energy ball-milled aluminium (Al) and nickel (Ni) powders at a composition corresponding to AlNi3 were investigated. The formation of a bi-modal structure ...

Article

Hydrogen production by ethylene decomposition over Ni supported on novel carbon nanotubes and nanofibers

Savva, Petros G.; Olympiou, G. G.; Costa, Costas N.; Ryzhkov, V. A.; Efstathiou, Angelos M. (2005)

Ethylene decomposition over Ni supported on novel carbon nanotubes (CNT) and nanofibers under consecutive reaction/regeneration cycles to form CO-free hydrogen and carbon deposits have been investigated. The present work ...

Article

Investigations on the self propagating reactions of nickel and aluminum multilayered foils

Gunduz, Ibrahim Emre; Fadenberger, K.; Kokonou, Maria; Rebholz, Claus; Doumanidis, C. C. (2008)

The self-propagating reaction of nickel-aluminum thin film multilayers with a bilayer thickness of 43 nm was investigated using high-speed optical camera and infrared thermometry. The results indicate a two-stage reaction ...

Article

Low-temperature catalytic decomposition of ethylene into H2 and secondary carbon nanotubes over Ni/CNTs

Savva, Petros G.; Polychronopoulou, Kyriaki; Ryzkov, V. A.; Efstathiou, Angelos M. (2010)

The present work reports on the production of H2 and secondary carbon nanotubes (CNTs) during catalytic decomposition of ethylene over a novel catalytic system, namely, nickel supported on carbon nanotubes (Ni/CNTs) at ...

Article

Mechanics and energetics modeling of ball-milled metal foil and particle structures

Aureli, M.; Doumanidis, C. C.; Gunduz, I. E.; Hussien, A. G. S.; Liao, Y.; Rebholz, Claus; Doumanidis, C. C. (2017)

The reported research establishes a semi-analytical computational predictive model of fractal microstructure in ball-milled metal foils and powder particulates, with emphasis on its transformation mechanics via an energy-based ...

Article

Novel Zn-Ti-based mixed metal oxides for low-temperature adsorption of H2S from industrial gas streams

Polychronopoulou, Kyriaki; Fierro, José Luis García; Efstathiou, Angelos M. (2005)

The efficiency of various Zn-Ti-based mixed metal oxides prepared by the sol-gel method towards H2S adsorption from a gas mixture containing 0.06 vol.% H2S, 25 vol.% H2, 7.5 vol.% CO2 and 1 vol.% H2O was studied in the ...

Article

Origin and reactivity of active and inactive carbon formed during DRM over Ni/Ce0.38Zr0.62O2-δ studied by transient isotopic techniques

Vasiliades, Michalis A.; Djinović, P.; Davlyatova, L. F.; Pintar, A.; Efstathiou, Angelos M. (2016)

The role of Ce0.38Zr0.62O2-δ redox support and that of reactants CH4 and CO2 in the carbon-path of dry reforming of methane (DRM) at 750°C over a 3wt% Ni/Ce0.38Zr0.62O2-δ catalyst were investigated. In particular, meticulously ...

Article

Simulations of nanoscale Ni/Al multilayer foils with intermediate Ni2Al3 growth

Gunduz, I. E.; Onel, S.; Doumanidis, C. C.; Rebholz, Claus; Son, S. F. (2015)

Nanoscale multilayers of binary metallic systems, such as nickel/aluminum, exhibit self-propagating exothermic reactions due to the high formation enthalpy of the intermetallic compounds. Most of the previous modeling ...

Article

Sn:In2O3 and Sn:In2O3/NiS2 Core-Shell Nanowires on Ni, Mo Foils and C Fibers for H2 and O2 Generation

Zervos, Matthew; Leontidis, E.; Tanasǎ, E.; Vasile, E.; Othonos, A. (2017)

Sn:In2O3 nanowires have been grown by the vapor liquid solid mechanism on Si, Ni, Mo, and C fibers. These were used to obtain Sn:In2O3/NiS2 core-shell nanowires by the deposition of 10 nm Ni over the Sn:In2O3 nanowires ...

Article

Spark ignitable ball milled powders of Al and Ni at NiAl composition

Hadjiafxenti, A.; Gunduz, I. E.; Doumanidis, C. C.; Rebholz, Claus (2014)

Low-energy ball milling of aluminum and nickel particles with an overall composition corresponding to the NiAl intermetallic phase was performed up to milling durations of 13 h. The milled powders and cold-compacted pellets ...

Article

Spark ignitable Ni-Al ball-milled powders for bonding applications

Gunduz, I. E.; Kyriakou, A.; Vlachos, N.; Kyratsi, Theodora; Doumanidis, C. C.; Son, S.; Rebholz, Claus (2014)

Ball milling of aluminum (Al) and nickel (Ni) particles at the NiAl composition can produce reactive powders with low spark ignition thresholds similar to magnetron sputtered multilayer foils (MFs). Such powders can replace ...

Article

Temperature programmed reduction of silica supported nickel catalysts

Afzal, M.; Theocharis, Charis R.; Karim, S. (1993)

Nickel oxide promoted catalysts are prepared by simple precipitation, precipitation from homogeneous solution and impregnation methods and their reduction behavior is monitored with temperature programmed reduction (TPR) ...