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Dmitri V. Alekseevsky Andreas Kriegl Mark Losik Peter W. Michor 《Annali di Matematica Pura ed Applicata》2007,186(1):25-58
We investigate discrete groups G of isometries of a complete connected Riemannian manifold M which are generated by reflections, in particular those generated by disecting reflections. We show that these are Coxeter
groups, and that the orbit space M/G is isometric to a Weyl chamber C which is a Riemannian manifold with corners and certain angle conditions along intersections of faces. We can also reconstruct
the manifold and its action from the Riemannian chamber and its equipment of isotropy group data along the faces. We also
discuss these results from the point of view of Riemannian orbifolds.
Mathematics Subject Classification Primary 51F15, 53C20, 20F55, 22E40 相似文献
66.
Alexey P. Ilyin Julia N. Peregudova Elena B. Poutsykina Dmitri V. Kravchenko 《Tetrahedron letters》2006,47(15):2649-2653
We present a convenient synthesis of heterocyclic scaffolds using a novel modification of four-component Ugi condensation. Two complementary variants of this useful synthetic strategy provide an efficient one-step assembly of four novel pharmaceutically relevant (hetero)aryl-fused 1,4-oxazepines with different substituents’ profile. 相似文献
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In this work we present a composite model, which combines the approach of Poisson's function with the filament theory and requires three material parameters. We also suggest the form for a strain-energy function that approximates the constitutive equations of the composite model. Furthermore, a simple asymptotic analysis allows us to reduce the number of material constants to only two, thus, forming a new filament model. The predictive capability of the two models to reproduce the mechanical behaviour of elastomeric materials in deformation experiments is evaluated against the extensive data of Kawabata et al. (Macromolecules 14 (1981) 154). The models give excellent agreement in not only uniaxial and equibiaxial but also non-equibiaxial extension. Although being rather more simplistic in comparison with some successful network models involving non-Gaussian chain statistics, the two models conform much more closely to the classical experimental data of Treloar (Trans. Faraday Soc. 40 (1944) 59). 相似文献
69.
Dmitri Neshumayev Arvo Ots Jaan Laid Toomas Tiikma 《Experimental Thermal and Fluid Science》2004,28(8):4343-886
This experimental research was focused on the investigation of the heat transfer augmentation by various turbulator inserts in gas-heated channels. The work was conducted directly in a convective part of a two fire-tube boiler. The flue ducts were positioned vertically and horizontally for various design applications. Twisted-tape insert (with the twist ratio y=4.12), the straight-tape insert, and the combined turbulator insert (the internal twisted tape with the twist ratio of 180° y=2.16 and an external tape, which spirally winded on an internal tape, with longitudinal pitch H360°=110 mm and the relative height of a tape (rib) e/D0=0.098;0.2) were investigated. The working fluids were the combustion products of light oil fuel and wood pellets. In addition, the experiments were conducted in the two fire-tube boiler without any inserts. Despite of relatively large data scattering obtained in these experiments some qualitative and quantitative conclusions were drawn. 相似文献
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Synthesis and Evaluation of GdIII‐Based Magnetic Resonance Contrast Agents for Molecular Imaging of Prostate‐Specific Membrane Antigen 下载免费PDF全文
Dr. Sangeeta Ray Banerjee Dr. Ethel J. Ngen Matthew W. Rotz Dr. Samata Kakkad Ala Lisok Richard Pracitto Mrudula Pullambhatla Dr. Zhengping Chen Dr. Tariq Shah Dr. Dmitri Artemov Dr. Thomas J. Meade Dr. Zaver M. Bhujwalla Dr. Martin G. Pomper 《Angewandte Chemie (International ed. in English)》2015,54(37):10778-10782
Magnetic resonance (MR) imaging is advantageous because it concurrently provides anatomic, functional, and molecular information. MR molecular imaging can combine the high spatial resolution of this established clinical modality with molecular profiling in vivo. However, as a result of the intrinsically low sensitivity of MR imaging, high local concentrations of biological targets are required to generate discernable MR contrast. We hypothesize that the prostate‐specific membrane antigen (PSMA), an attractive target for imaging and therapy of prostate cancer, could serve as a suitable biomarker for MR‐based molecular imaging. We have synthesized three new high‐affinity, low‐molecular‐weight GdIII‐based PSMA‐targeted contrast agents containing one to three GdIII chelates per molecule. We evaluated the relaxometric properties of these agents in solution, in prostate cancer cells, and in an in vivo experimental model to demonstrate the feasibility of PSMA‐based MR molecular imaging. 相似文献