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111.
Burkhard Kleihaus Jutta Kunz Francisco Navarro-Lérida Ulrike Neemann 《General Relativity and Gravitation》2008,40(6):1279-1310
We consider globally regular and black hole solutions in SU(2) Einstein–Yang–Mills–Higgs theory, coupled to a dilaton field.
The basic solutions represent magnetic monopoles, monopole–antimonopole systems or black holes with monopole or dipole hair.
When the globally regular solutions carry additionally electric charge, an angular momentum density results, except in the
simplest spherically symmetric case. We evaluate the global charges of the solutions and their effective action, and analyze
their dependence on the gravitational coupling strength. We show, that in the presence of a dilaton field, the black hole
solutions satisfy a generalized Smarr type mass formula.
B. Kleihaus gratefully acknowledges support by the German Aerospace Center.
F. Navarro-Lérida gratefully acknowledges support by the Ministerio de Educación y Ciencia under grant EX2005-0078. 相似文献
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Matthias Weil PD Dr. 《无机化学与普通化学杂志》2007,633(8):1217-1222
Single crystals of a third modification of Ag2Te2O6 (denoted as Ag2Te2O6–III) and of Ag4TeO5 have been obtained as minor by‐products during hydrothermal phase formation experiments in the system Ag‐Hg‐Te‐O. The crystal structure of Ag2Te2O6–III (P21/c, Z = 4, a = 6.4255(10), b = 6.9852(11), c = 13.204(2) Å, β = 90.090(3)°, 1885 independent reflections, R[F2 > 2σ(F2)] = 0.0334, wR2(F2 all) = 0.0817) comprises tellurium in oxidation states +IV and +VI and is topologically related to the structure of the Ag2Te2O6–I modification, which consists of similar layers and interjacent layers of Ag+ cations. Ag4TeO5 (C2/c, Z = 8, a = 16.271(2), b = 6.0874(10), c = 11.4373(16) Å, β = 106.730(10)°, 2372 independent reflections, R[F2 > 2σ(F2)] = 0.0288, wR2(F2 all) = 0.0737) is made up of a layer‐like arrangement of isolated [TeVI2O10] double octahedra and of Ag+ cations situated both in layers parallel and inside the layers of the anionic moieties. 相似文献
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DallyMoya Argilagos Roland W. Kunz Anthony Linden Heinz Heimgartner 《Helvetica chimica acta》1998,81(12):2388-2406
The course of the desulfurization reaction of 4-nitro-N,2-diphenyl-3-(phenylamino)isothiazol-5(2H)-imine ( 3 ) is investigated and the formation of the unstable 3-imino-2-nitroprop-2-enamidine ( A ) as intermediate is discussed. Addition of amines and thiophenol to the reaction mixture yielded the amidine derivatives 5 and the thioimidate 6 , respectively, via nucleophilic addition of the respective reagent to A (Scheme 2). Benzoic acid and thiobenzoic acid afforded the amide 7 and the thioamide 8 , respectively, as secondary products of the expected adducts 7a and 8a (Schemes 3 and 4). The presence of (benzylidene)(methyl)amine in the reaction mixture of the desulfurization of 3 led to the 1,2,4-oxadiazole derivative 10 , together with the quinoxaline N-oxide 4 as a minor product. Reaction mechanisms involving an intermediate ketene imine and participation of the NO2 group in the reaction leading to 1,2,4-oxadiazole 10 are proposed. Ab initio calculations of model structures for the nitroketene imine were performed and the results correlated with the experimental results. The structures of 8 and 10 were established by X-ray crystal-structure analysis. 相似文献
117.
Tobias Wunberg Christopher Kallus Till Opatz Stefan Henke Wolfgang Schmidt Horst Kunz 《Angewandte Chemie (International ed. in English)》1998,37(18):2503-2505
Four orthogonally stable protecting groups and a selectively cleavable anchor that are stable under basic conditions are required in order that carbohydrates can be employed as chiral polyfunctional scaffolds in combinatorial solid-phase syntheses of high diversity. The schematic representation shows the combinatorial synthesis with a carbohydrate scaffold (SG=protecting group, A=anchor, P=polymer carrier), which proceeds by sequential selective deprotection, functionalization, washing of the solid phase, and cleavage of the anchor. 相似文献
118.
Solid energetic substances have long played an important technological role as explosives, as well as for fuels. In this article, the authors concentrate on a type of explosive considered a primary explosive, lead azide, and its related compounds, lithium azide and sodium azide. Recent interest in more fundamental questions relating to the basic properties of these systems as materials, coupled with a desire to probe fundamental questions relating to the initiation and sustaining of the chemical reactions leading to combustion/detonation, is generating significant interest in the basic solid-state properties of such energetic systems. In particular, recent analysis of detonation by Gilman emphasizes the need to include excitation of the electronic system in obtaining an understanding. In this article, the band structures of the three solid metal azides are studied. This is done for both the normal lattice geometry and also in isotropically compressed geometries. These studies found that the alkali azide band gaps are far wider than is the lead azide gap and the lead azide gap is far more sensitive to narrowing with lattice compression than are the gaps for the alkali azides. In fact, the gap for sodium azide is found to widen with compression rather than narrow. The authors found that there is much seen in the band structures of these azides to lend some support to the Gilman model and also to demonstrate the importance of solid-state effects on the electronic structure and possible behavior of such energetic systems. © 1997 John Wiley & Sons, Inc. 相似文献
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Dr. Dominique Bruns Dr. Daniel Merk Dr. Karthiga Santhana Kumar PD Dr. Martin Baumgartner Prof. Dr. Gisbert Schneider 《ChemistryOpen》2019,8(10):1303-1308
Constructive machine learning aims to create examples from its learned domain which are likely to exhibit similar properties. Here, a recurrent neural network was trained with the chemical structures of known cell-migration modulators. This machine learning model was used to generate new molecules that mimic the training compounds. Two top-scoring designs were synthesized, and tested for functional activity in a phenotypic spheroid cell migration assay. These computationally generated small molecules significantly increased the migration of medulloblastoma cells. The results further corroborate the applicability of constructive machine learning to the de novo design of druglike molecules with desired properties. 相似文献