Development of GCP Ontology for sharing crop information

Poster presented at 3rd International Biocuration Conference. Berlin (Germany), 17 Apr 200

Strange Particles and Neutron Stars - Experiments at Gsi

Experiments on strangeness production in nucleus-nucleus collisions at SIS energies address fundamental aspects of modern nuclear physics: the determination of the nuclear equation-of-state at high baryon densities and the properties of hadrons in dense nuclear matter. Experimental data and theoretical results will be reviewed. Future experiments at the FAIR accelerator aim at the exploration of the QCD phase diagram at highest baryon densities.Comment: %Invited talk given at the International Invited talk given at the International Symposium on Heavy Ion Physics (ISHIP 2006) April 3-6 2006, FIAS, Frankfurt, Germany Frankfurt, German

Quantum Transport Characteristics of Lateral pn-Junction of Single Layer TiS3

Using density functional theory and nonequilibrium Greens functions-based methods we investigated the electronic and transport properties of monolayer TiS3 pn-junction. We constructed a lateral pn-junction in monolayer TiS3 by using Li and F adatoms. An applied bias voltage caused significant variability in the electronic and transport properties of the TiS3 pn-junction. In addition, spin dependent current-voltage characteristics of the constructed TiS3 pn-junction were analyzed. Important device characteristics were found such as negative differential resistance and rectifying diode behaviors for spin-polarized currents in the TiS3 pn-junction. These prominent conduction properties of TiS3 pn-junction offer remarkable opportunities for the design of nanoelectronic devices based on a recently synthesized single-layered material

Ag and Au Atoms Intercalated in Bilayer Heterostructures of Transition Metal Dichalcogenides and Graphene

The diffusive motion of metal nanoparticles Au and Ag on monolayer and between bilayer heterostructures of transition metal dichalcogenides and graphene are investigated in the framework of density functional theory. We found that the minimum energy barriers for diffusion and the possibility of cluster formation depend strongly on both the type of nanoparticle and the type of monolayers and bilayers. Moreover, the tendency to form clusters of Ag and Au can be tuned by creating various bilayers. Tunability of the diffusion characteristics of adatoms in van der Waals heterostructures holds promise for controllable growth of nanostructures.Comment: accepted, APL Ma

Turning the Ship of State

In his thoughtful article on the future of ADR, Professor Frank Sander notes, On Monday, Wednesday and Friday, I think we\u27ve made amazing progress. On Tuesday, Thursday and Saturday, ADR seems more like a grain of sand on the adversary system beach. \u27 In the federal government, I believe things are somewhat better than that. Perhaps five days out of seven I am impressed with the progress of the government in implementing ADR, particularly in the last ten years, which I will describe below. The other two days, like Professor Sander, I become more discouraged as we run into one of many barriers, which I will also describe below. The United States government is a big ship that doesn\u27t make tight turns, but there has been remarkable progress in this fiel

Directed Growth of Hydrogen Lines on Graphene: High Throughput Simulations Powered by Evolutionary Algorithm

We set up an evolutionary algorithm combined with density functional tight-binding (DFTB) calculations to investigate hydrogen adsorption on flat graphene and graphene monolayers curved over substrate steps. During the evolution, candidates for the new generations are created by adsorption of an additional hydrogen atom to the stable configurations of the previous generation, where a mutation mechanism is also incorporated. Afterwards a two-stage selection procedure is employed. Selected candidates act as the parents of the next generation. In curved graphene, the evolution follows a similar path except for a new mechanism, which aligns hydrogen atoms on the line of minimum curvature. The mechanism is due to the increased chemical reactivity of graphene along the minimum radius of curvature line (MRCL) and to sp$^3$ bond angles being commensurate with the kinked geometry of hydrogenated graphene at the substrate edge. As a result, the reaction barrier is reduced considerably along the MRCL, and hydrogenation continues like a mechanical chain reaction. This growth mechanism enables lines of hydrogen atoms along the MRCL, which has the potential to overcome substrate or rippling effects and could make it possible to define edges or nanoribbons without actually cutting the material.Comment: 10 pages of main text, 37 pages of supplementary information, 1 supplementary vide

How many phases meet at the chiral critical point?

We explore the phase diagram of NJL-type models near the chiral critical point allowing for phases with spatially inhomogeneous chiral condensates. In the chiral limit it turns out that the region in the mean-field phase diagram where those phases are energetically preferred very generically reaches out to the chiral critical point. The preferred inhomogeneous ground state in this vicinity possibly resembles a lattice of domain wall solitons. This raises the question of their relevance for the phase diagram of QCD.Comment: 7 pages, 1 figure; v2: minor corrections, as published in PR