Browsing by Subject "X ray diffraction analysis"

Article

Antiferromagnetic interactions in 1D Heisenberg linear chains of 7-(4-fluorophenyl) and 7-phenyl-substituted 1,3-diphenyl-1,4-dihydro- 1,2,4-benzotriazin-4-yl radicals

Constantinides, Christos P.; Koutentis, Panayiotis Andreas; Rawson, J. M. (2012)

7-(4-Fluorophenyl) and 7-phenyl-substituted 1,3-diphenyl-1,4-dihydro-1,2,4- benzotriazin-4-yl radicals were characterized by X-ray diffraction analysis and variable-temperature magnetic susceptibility studies. The radicals ...

Article

Bi/Sb distribution and its consequences in solid solution members of the thermoelectric materials K2Bi8-xSbxSe13

Kyratsi, Theodora; Chung, D. Y.; Kanatzidis, M. G. (2002)

In an effort to understand the nature of mass fluctuations introduced when β-K2Bi8Se13 is alloyed with K2Sb8Se13 we determined the detailed crystal structures of two solid solutions of the type K2Bi8-xSbxSe13 with x=4.0 ...

Article

Catalytic behavior of La-Sr-Ce-Fe-O mixed oxidic/perovskitic systems for the NO+CO and NO+CH4+O2 (lean-NOx) reactions

Belessi, Vassiliki C.; Costa, Costas N.; Bakas, Thomas V.; Anastasiadou, T.; Pomonis, Phillippos J.; Efstathiou, Angelos M. (2000)

Mixed oxides of the general formula La0.5SrxCeyFeOz were prepared by using the nitrate method and characterized by XRD and Mossbauer techniques. The crystal phases detected were perovskites LaFeO3 and SrFeO3-x and oxides ...

Article

Design of ball-milling experiments on Bi2Te3 thermoelectric material

Kanatzia, A.; Papageorgiou, Ch; Lioutas, Ch; Kyratsi, Theodora (2013)

In this work, factorial ball-milling experiments have been applied to Bi2Te3 material, for the first time, aiming to investigate the effect of the main process parameters on the structural features and thermoelectric ...

Article

Effects of calcination temperature on the stability of CePO4 detected in vehicle-aged commercial three-way catalysts

Larese, C.; Cabello Galisteo, F.; López Granados, M.; Mariscal López, R.; Fierro, José Luis García; Lambrou, Panayiota S.; Efstathiou, Angelos M. (2004)

Samples extracted from a vehicle-aged commercial TWC monolith (the inlet part of the first cartridge) have been shown to contain CePO4. The effects of calcination temperature in the 773-1173K range on these samples have ...

Article

Fabrication and characterization of superparamagnetic and thermoresponsive hydrogels based on oleic-acid-coated Fe3O4 nanoparticles, hexa(ethylene glycol) methyl ether methacrylate and 2-(acetoacetoxy)ethyl methacrylate

Papaphilippou, P.; Pourgouris, A.; Marinica, O.; Taculescu, A.; Athanasopoulos, G. I.; Vekas, L.; Krasia-Christoforou, T. (2011)

Stimuli-responsive hydrogel nanocomposites comprised of swollen polymer networks, in which magnetic nanoparticles are embedded, are a relatively new class of "smart" soft materials presenting a significant impact on various ...

Article

Femtosecond carrier dynamics of Inx Ga1-x N thin films grown on GaN (0001): Effect of carrier-defect scattering

Lioudakis, Emmanouil E.; Othonos, Andreas S.; Iliopoulos, Eleftherios; Tsagaraki, K.; Georgakilas, A. (2007)

Ultrafast carrier dynamics in ultrathin Inx Ga1-x N ternary alloys were investigated in detail, using femtosecond transient differential optical absorption measurements. Measurements were performed with probing wavelengths ...

Article

From beads-on-a-string to colloidal aggregation: novel crystallization phenomena in the PEO-SDS system

Leontidis, Epameinondas; Kyprianidou-Leodidou, Tasoula; Caseri, Walter; Kyriacou, Kyriacos C. (1999)

The anionic surfactant sodium dodecyl sulfate (SDS) interacts strongly with poly(ethylene oxide) (PEO) in aqueous solution, forming micellar aggregates attached to the polymer chains above the so-called critical association ...

Article

From colloidal aggregates to layered nanosized structures in polymer-surfactant systems. 1. Basic phenomena

Leontidis, Epameinondas; Kyprianidou-Leodidou, Tasoula; Caseri, Walter; Robyr, P.; Krumeich, F.; Kyriacou, Kyriacos C. (2001)

In this work, we examine the rich crystallization behavior that occurs in PbII/S-II/poly(ethylene oxide) (PEO)/sodium dodecyl sulfate (SDS) systems, in which the anionic surfactant interacts strongly with the polymer ...

Article

Investigation of the synthesis and properties of ternary V-Cu-Ce Oxides of Composition VxCuxCe1-2xO2

Attipa, Christothea; Theocharis, Charis R. (2009)

Aco-precipitation method has been used to prepare ternary mixed oxides based on ceria with the general formula VxCuxCe 1-2xO2, where x was varied between 0.05 and 0.45. The structural and surface properties as well as the ...

Article

KSb5S8: A wide bandgap phase-change material for ultra high density rewritable information storage

Kyratsi, Theodora; Chrissafis, K.; Wachter, J.; Paraskevopoulos, K. M.; Kanatzidis, M. G. (2003)

The reversible glassformation and glass crystallization properties of KSb3S8 was described. On the basis of glass transition and crystallization kinetics of KSb5S8, it was found that the crystallization rate and assoicated ...

Article

LaSrMnCoO6: A new cubic double perovskite oxide

Androulakis, J.; Katsarakis, N.; Giapintzakis, John; Vouroutzis, N.; Pavlidou, E.; Chrissafis, K.; Polychroniadis, E. K.; Perdikatsis, V. (2003)

Single-phase polycrystalline powder samples of the double perovskite oxide LaSrMnCoO6 were synthesized by the Pechini (citrate-gel) technique. The structural, magnetic and electrical properties of the obtained powders were ...

Article

Magnetic properties of Fe/AlO x/GaAs(001) structures

Vaz, C. A. F.; Ionescu, A.; Trypiniotis, Theodossis; Bland, J. A. C.; Dalgliesh, R. M.; Langridge, S. (2005)

We report results on the effect of the Al Ox barrier layer on the magnetic moment of Fe using polarized neutron reflection. The sample has nominal composition 25 nm Au5 nm Fe1.3 nm Al Ox GaAs (001). The metal deposition ...

Article

Magnetic properties of the half-metallic ferromagnet NiMnSb grown on InSb by pulsed laser deposition

Androulakis, J.; Gardelis, S.; Giapintzakis, John; Buckle, P. D. (2004)

We have grown films of the half-metallic ferromagnet NiMnSb on single crystals of the narrow gap semiconductor InSb by pulsed laser deposition. NiMnSb is a possible candidate for spin injection applications. The film ...

Article

Nanostructure, mechanical and tribological properties of reactive magnetron sputtered TiCx coatings

Polychronopoulou, K.; Rebholz, Claus; Baker, M. A.; Theodorou, L.; Demas, N. G.; Hinder, S. J.; Polycarpou, A. A.; Doumanidis, C. C.; Böbel, K. (2008)

This study describes the correlation between microstructure, mechanical and tribological properties of TiCx coatings (with x being in the range of 0-1.4), deposited by reactive magnetron sputtering from a Ti target in ...

Article

The nanostructure, wear and corrosion performance of arc-evaporated CrBxNy nanocomposite coatings

Polychronopoulou, K.; Baker, M. A.; Rebholz, Claus; Neidhardt, J.; O'Sullivan, M.; Reiter, A. E.; Kanakis, K.; Leyland, A.; Matthews, A.; Mitterer, C. (2009)

The composition, nanostructure, tribological and corrosion behaviour of reactive arc evaporated CrBxNy coatings have been studied and compared to CrN. The CrBxNy coatings were deposited on a commercial Oerlikon Balzers RCS ...

Article

New antimony(III) halide complexes with dithiocarbamate ligands derived from thiuram degradation: The effect of the molecule's close contacts on in vitro cytotoxic activity

Urgut, O. S.; Ozturk, I. I.; Banti, Christina N.; Kourkoumelis, Nikolaos; Manoli, Maria; Tasiopoulos, Anastasios J.; Hadjikakou, Sotiris K. (2016)

Antimony(III) halide complexes of the formulae {[SbBr(Me2DTC)2]n} (1), {[SbI(Me2DTC)2]n} (2) and {[(Me2DTC)2Sb(μ2-I)Sb(Me2DTC)2]+.I3-} (3) (Me2DTC = dimethyldithiocarbomate) were synthesized from SbX3, (X = Br or I) and ...

Article

PLD of Fe3O4 thin films: Influence of background gas on surface morphology and magnetic properties

Paramês, M. L.; Mariano, J.; Viskadourakis, Z.; Popovici, N.; Rogalski, M. S.; Giapintzakis, John; Conde, O. (2006)

Ablation of Fe3O4 targets has been performed using a pulsed UV laser (KrF, λ = 248 nm, 30 ns pulse duration) onto Si(100) substrates, in reactive atmospheres of O2 and/or Ar, with different oxygen partial pressures. The ...

Article

Preparation and characterization of a cerium(IV)-incorporated manganese oxide OMS-2. Effect of cerium(IV) template on octahedral molecular sieves of manganese oxide and characterization of manganese oxide molecular sieves with cerium(IV) as dopant

Hapeshi, Evroula; Theocharis, Charis R. (2008)

The manganese oxide material K-OMS-2 was synthesized both via a redox reaction between potassium permanganate and manganese nitrate in an acidic medium (nitric acid) under reflux conditions and by the sol-gel reaction ...

Article

Reaction of tetracyanoethylene with SCl1

Koutentis, Panayiotis Andreas; Rces, C. W. (2000)

The chloride ion catalysed addition of SCl2 to TCNE gives the 4-dicyanomethylene-l,2,6-thiadiazine 2 (60%) with two minor products (5%) of extensive molecular rearrangement, the pyrimidine 4 and the pyrroloimidazothiadiazine ...