Au+Au central collisions at 150, 250 and 400 AMeV energies in QMD with relativistic forces

An extensive comparison of the recent experimental data published by the FOPI collaboration at GSI with the results of a relativistically covariant formulation of a QMD code is presented. For most of the quantities we find agreement with the experimental results showing that the derived force has a reasonable momentum dependence.Comment: 33 pages with 18 EPSF figures included. Final version to appear in Nucl. Phys.

Three-body confinement force in a realistic constituent quark model

We show that in realistic constituent quark models based on a two-body confinement interaction color states appear in the middle of the experimentally known spectrum. To avoid this situation we implement a three-body confinement interaction, introduced on an algebraic basis, into a semirelativistic version of the Goldstone-boson-exchange constituent quark model and by solving the Faddeev equations we show that this interaction can increase the gap between singlet and colour states, such as the latter can be ignored and the known baryons can be described as $q^3$ systems. We analyze the effect of a $\Delta$- and a Y-shape three-body interaction.Comment: 14 pages, 3 figures, revised version to appear in Nucl. Phys.

Selective Hydration of Nitriles to Corresponding Amides in Air with Rh(I)-N-Heterocyclic Complex Catalysts

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Other rooms, other texts, other selves: Alice Munro’s “Sunday afternoon” and “Hired Girl”

La nouvelle "Hired Girl" d'Alice Munro, se veut une suite qui, non seulement complète "Sunday Afternoon" mais aussi porte un regard critique sur celle-ci en ayant recours à un point de vue plus complexe : d'une adolescente sur la défensive - l'héroîne de "Sunday Afternoon" - Munro passe à un narrateur adulte qui se penche sur son passé et s'adonne à une autocritique ; à travers l'ironie de l'intertexte, ce narrateur commente de manière metatextuelle les deux histoires mais aussi définit l'identité de Munro, l'auteur

Other rooms, other texts, other selves: Alice Munro’s “Sunday afternoon” and “Hired Girl”

La nouvelle "Hired Girl" d'Alice Munro, se veut une suite qui, non seulement complète "Sunday Afternoon" mais aussi porte un regard critique sur celle-ci en ayant recours à un point de vue plus complexe : d'une adolescente sur la défensive - l'héroîne de "Sunday Afternoon" - Munro passe à un narrateur adulte qui se penche sur son passé et s'adonne à une autocritique ; à travers l'ironie de l'intertexte, ce narrateur commente de manière metatextuelle les deux histoires mais aussi définit l'identité de Munro, l'auteur

Key Parameters for the Synthesis of Active and Selective Nanostructured 3d Metal Catalysts Starting from Coordination Compounds – Case Study: Nickel Mediated Reductive Amination

The design of nanostructured catalysts based on earth-abundant metals that mediate important reactions efficiently, selectively and with a broad scope is highly desirable. Unfortunately, the synthesis of such catalysts is poorly understood. We report here on highly active Ni catalysts for the reductive amination of ketones by ammonia employing hydrogen as a reducing agent. The key functions of the Ni-salen precursor complex during catalyst synthesis have been identified: (1) Ni-salen complexes sublime during catalyst synthesis, which allows molecular dispersion of the metal precursor on the support material. (2) The salen ligand forms a nitrogen-doped carbon shell by decomposition, which embeds and stabilizes the Ni nanoparticles on the γ-Al2O3 support. (3) Parameters, such as flow rate of the pyrolysis gas, determine the carbon supply for the embedding process of Ni nanoparticles

Key Parameters for the Synthesis of Active and Selective Nanostructured 3d Metal Catalysts Starting from Coordination Compounds – Case Study: Nickel Mediated Reductive Amination

The design of nanostructured catalysts based on earth-abundant metals that mediate important reactions efficiently, selectively and with a broad scope is highly desirable. Unfortunately, the synthesis of such catalysts is poorly understood. We report here on highly active Ni catalysts for the reductive amination of ketones by ammonia employing hydrogen as a reducing agent. The key functions of the Ni-salen precursor complex during catalyst synthesis have been identified: (1) Ni-salen complexes sublime during catalyst synthesis, which allows molecular dispersion of the metal precursor on the support material. (2) The salen ligand forms a nitrogen-doped carbon shell by decomposition, which embeds and stabilizes the Ni nanoparticles on the γ-Al2O3 support. (3) Parameters, such as flow rate of the pyrolysis gas, determine the carbon supply for the embedding process of Ni nanoparticles

General and selective deoxygenation by hydrogen using a reusable earth-abundant metal catalyst

Chemoselective deoxygenation by hydrogen is particularly challenging but crucial for an efficient late-stage modification of functionality-laden fine chemicals, natural products, or pharmaceuticals and the economic upgrading of biomass-derived molecules into fuels and chemicals. We report here on a reusable earth-abundant metal catalyst that permits highly chemoselective deoxygenation using inexpensive hydrogen gas. Primary, secondary, and tertiary alcohols as well as alkyl and aryl ketones and aldehydes can be selectively deoxygenated, even when part of complex natural products, pharmaceuticals, or biomass-derived platform molecules. The catalyst tolerates many functional groups including hydrogenation-sensitive examples. It is efficient, easy to handle, and conveniently synthesized from a specific bimetallic coordination compound and commercially available charcoal. Selective, sustainable, and cost-efficient deoxygenation under industrially viable conditions seems feasible. © 2019 The Authors

The Phase Diagram of the Quark-Meson Model

Within the proper-time renormalization group approach, the chiral phase diagram of a two-flavor quark-meson model is studied. In the chiral limit, the location of the tricritical point which is linked to a Gaussian fixed point, is determined. For quark chemical potentials smaller than the tricritical one the second-order phase transition belongs to the O(4) universality class. For temperatures below the tricritical one we find initially a weak first-order phase transition which is commonly seen in model studies and also in recent lattice simulations. In addition, below temperatures of T <~ 17 MeV we find two phase transitions. The chiral restoration transition is initially also of first-order but turns into a second-order transition again. This leads to the possibility that there may be a "second tricritical" point in the QCD phase diagram in the chiral limit.Comment: 19 pages, 4 figures,v2; minor corrections in the text, references added, slightly extended conclusion, to appear in NP