Search results for "SPLIT"
showing 10 items of 362 documents
Ni-Fe alloy nanostructured electrodes for water splitting in alkaline electrolyser
2021
Abstract In this work, nickel-iron alloy nanostructured electrodes obtained by template electrosynthesis method are investigated for both hydrogen and oxygen evolution reactions. Electrodes consist of nanowire arrays with high surface area that are able to ensures a high electrolytic activity. To obtain different alloy compositions, the concentration of the elements in the deposition baths is appropriately tuned. Results show that the composition of nanowires does not change linearly with the composition of deposition bath but are richer in Fe. Nanostructured electrodes are tested as both cathodes and anodes in 30 wt% KOH aqueous solution, at room temperature to determine the best alloy com…
Efficient H2 production by photocatalytic water splitting under UV or solar light over variously modified TiO2-based catalysts
2019
Abstract This paper focused for the first time on the comparison between three different approach to modify the chemico-physical properties of TiO2-based photocatalysts and their effect in the H2 production by photocatalytic water splitting both under UV and solar light irradiation, under the same experimental conditions. The application of pulsed laser irradiation to aqueous TiO2 suspensions (first approach) induced structural transformations both on the bulk and on the surface of TiO2, boosting the H2 production, under UV light irradiation, of almost three times (20.9 mmol/gcat·h) compared to bare TiO2 (7.7 mmol/gcat·h). The second strategy was based on a templating method to obtain TiO2 …
New coordination polymers based on a novel polynitrile ligand: Synthesis, structure and magnetic properties of the series [M(tcnoetOH)2(4,4′-bpy)(H2O…
2008
International audience; A novel polynitrile anionic ligand, tcnoetOH−(=[(NC)2CC(OCH2CH2OH)C(CN)2]−), has been synthesized by a one-pot reaction from a cyclic acetal and malononitrile. This ligand has been successfully used to prepare, with 4,4′-bpy as co-ligand, a novel series of coordination polymers formulated as [M(tcnoetOH)2(4,4′-bpy)(H2O)2] with M(II) = Fe (1), Co (2) and Ni (3). These isostructural compounds present a linear chain structure consisting of octahedrally coordinated metal ions bridged by trans 4,4′-bpy ligands. The coordination sphere of the metal ions is completed with two terminal tcnoetOH− ligand and two water molecules. The magnetic properties indicate that the three …
Structure and Properties of YbZnSn, YbAgSn, and Yb2Pt2Pb
1999
Abstract YbZnSn, YbAgSn, and Yb2Pt2Pb were synthesized by reacting the elements in sealed tantalum tubes in a high-frequency furnace. The structures of YbAgSn and Yb2Pt2Pb were refined from single crystal X-ray data: YbAgPb type, P 6 m2, a=479.2(2) pm, c=1087.3(3) pm, wR2=0.050, BASF=0.34(8), 509 F2 values, 18 variables for YbAgSn and Er2Au2Sn type, a=776.0(1) pm, c=701.8(2) pm, wR2=0.072, 426 F2 values, 18 variables for Yb2Pt2Pb. The lattice constants of YbZnSn are confirmed: NdPtSb type, P63mc, a=464.7(1) pm, c=747.7(2) pm. The stannides YbZnSn and YbAgSn crystallize with superstructures of the AlB2 type. The zinc (silver) and tin atoms form ordered Zn3Sn3 and Ag3Sn3 hexagons, respectivel…
Slow magnetic relaxation and water oxidation activity of dinuclear CoIICoIII and unique triangular CoIICoIICoIII mixed-valence complexes
2020
Construction of efficient multifunctional materials is one of the greatest challenges of our time. We herein report the magnetic and catalytic characterization of dinuclear [CoIIICoII(HL1)2(EtOH)(H2O)]Cl·2H2O (1) and trinuclear [CoIIICoII2(HL2)2(L2)Cl2]·3H2O (2) mixed valence complexes. Relevant structural features of the complexes have been mentioned to correlate with their magnetic and catalytic properties. Unique structural features, especially in terms of significant distortions around the CoII centre(s), prompted us to test both spin–orbit coupling (SOC) and zero field splitting (ZFS) methodologies for the systems. The positive sign of D values has been established from X-band EPR spec…
Power Losses Minimization for Optimal Operating Maps in Power-Split HEVs: A Case Study on the Chevrolet Volt
2021
The power-split architecture is the most promising hybrid electric powertrain. However, a real advantage in energy saving while maintaining high performance can be achieved only by the implementation of a proper energy management strategy. This requires an optimized functional design before and a comprehensive analysis of the powertrain losses after, which could be rather challenging owing to the constructive complexity of the power-split transmission, especially for multi-mode architecture with multiple planetary gearing. This difficulty was overcome by a dimensionless model, already available in the literature, that enables the analysis of any power-split transmission, even in full electr…
Ultrastable Holographic Cyclic Interferometer
1990
ABSTRACT We propose to use an off-axis zone plate, as beam splitter and as beam recombiner, to set a cyclic interferometer. We show that this optical device can be tuned to generate, with high stability, cosinusoidal gratings and/or cosinusoidal zone plates. 1. INTRODUCTION Several modern optical devices incorporate holographically generated optical elements; either for substituting conventional optical elements, or for introducing novel techniques for manipulating light.In particular, in the field of interferometry there are attemps to use diffracting ele ments for testing large optics; without using large beam splitters1"^.The aim of this work is to suggest, and to experimentally verify,…
2D slab models of TiO2 nanotubes for simulation of water adsorption: Validation over a diameter range
2020
Financial support provided by Scientific Research Project for Students and Young Researchers Nr. SJZ/2019/2 realized at the Institute of Solid State Physics, University of Latvia is greatly acknowledged. Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under Grant Agreement No. 739508, project CAMART 2 .
Preparation and XAFS studies of organotin(IV) complexes with adenosine and related compounds and calf thymus DNA
2007
Complexes of adenosine and related compounds (adenosine-5’-monophosphate, adenosine-5’-triphosphate and pyridoxal-5-phosphate) with Bu2SnO and/or BuSnCl2 were prepared in the solid state. The compositions of the complexes were determined by standard analytical methods. It was found that the complexes contain the organotin(IV) moiety and the ligand in a ratio of 1:1. The FT-IR spectra demonstrated that Bu2SnO reacts with the D-ribose moiety of the ligands, while Bu2SnCl2 is coordinated to the deprotonated phosphate group. The basic part of the ligands does not participate directly in complex formation. Comparison of the experimental Mossbauer Δ (quadrupole splitting) values with those calcul…
Dynamic instability in absence of dominated splittings.
2006
We want to understand the dynamics in absence of dominated splittings. A dominated splitting is a weak form of hyperbolicity where the tangent bundle splits into invariant subbundles, each of them is more contracted or less expanded by the dynamics than the next one. We first answer an old question from Hirsch, Pugh and Shub, and show the existence of adapted metrics for dominated splittings.Mañé found on surfaces a $C^1$-generic dichotomy between hyperbolicity and Newhouse phenomenons (infinitely many sinks/sources). For that purpose, he showed that without a strong enough dominated splitting along one periodic orbit, a $C^1$-perturbation creates a sink or a source. We generalise that last…