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951.
Victor Marcelo Deflon Karl Eberhard Bessler Martin Kretschmar Ulrich Abram 《无机化学与普通化学杂志》2000,626(7):1545-1549
Tris[3‐hydroxy‐2(1 H)‐pyridinonato] Complexes of Al3+, Cr3+, and Fe3+ – Crystal and Molecular Structures of 3‐Hydroxy‐2(1 H)‐pyridinone and Tris[3‐hydroxy‐2(1 H)‐pyridinonato]chromium(III) Tris[3‐hydroxy‐2(1 H)‐pyridinonato] complexes of Al3+, Cr3+ and Fe3+ are obtained by reactions of 3‐hydroxy‐2(1 H)pyridinone with the hydrates of AlCl3, CrCl3 or Fe(NO3) in aqueous alkaline solutions as polycrystalline precipitates. The compounds are isotypic. X‐ray structure determinations were performed on single crystals of the uncoordinated 3‐hydroxy‐2(1 H)‐pyridinone ( 1 ) (orthorhombic, space group P212121, a = 405.4(1), b = 683.0(1), c = 1770.3(3) pm, Z = 4) and of the chromium compound 3 (rhombohedral with hexagonal setting, space group R3c, a = 978.1(1), c = 2954.0(1) pm, Z = 6). 相似文献
952.
In this paper we determine a very particular example of a Picard modular variety of general type. On its non-singular models there exist many holomorphic differential forms. In a forthcoming paper we will show that one can construct Calabi–Yau manifolds by considering quotients of this variety and resolving singularities. 相似文献
953.
Eberhard Widmann 《Hyperfine Interactions》2014,229(1-3):123-128
The CRYRING accelerator, previously located at the Manne Siegbahn Laboratory of Stockholm University, has been chosen by the FLAIR collaboration as the central accelerator for the planned facility. It has been modified to allow for high-energy injection and extraction and is capable of providing fast and slow extracted beams of antiprotons and highly charged ions. It is currently being installed at the ESR of GSI Darmstadt where it can be used with highly charged ions. The future possibilities for its use with slow antiprotons will be discussed. 相似文献
954.
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956.
We propose a theoretical model for spatial variations of the temperature variance σ~2( z, r)( z is the distance from the sample bottom and r the radial coordinate) in turbulent Rayleigh-Bénard convection(RBC).Adapting the "attached-eddy" model of shear flow to the plumes of RBC, we derived an equation for σ~2 which is based on the universal scaling of the normalized RBC temperature spectra. This equation includes both logarithmic and power-law dependences on z/λ_(th), where λ_(th) is the thermal boundary layer thickness. The equation parameters depend on r and the Prandtl number Pr, but have only an extremely weak dependence on the Rayleigh number Ra Thus our model provides a near-universal equation for the temperature variance profile in turbulent RBC. 相似文献
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958.
A basic method to calculate van der Waals dispersion force distributions for submicron superquadric particles in particle-wall systems is presented. The force distribution is achieved by rotating particles through a large number of arbitrary spatial orientations, each time keeping constant the contact distance to the wall surface while calculating the dispersion force. To accomplish this, the use of 2D particle shape suffices, that is, through using an inter-dimensional function, which has been determined previously. A further development of the method within digital image analysis may lead to possible applications to forecasting the macroscopic properties of particle systems, for example, flowability, agglomeration behavior or dispersibility. For small ranges of superquadric particle shapes, each with a different size, the way from determining the inter-dimensional function up to applying image analysis is shown in an example. 相似文献
959.
Bemerkungen zu einem Satze von S. Bernstein aus der Theorie der elliptischen Differentialgleichungen
Eberhard Hopf 《Mathematische Zeitschrift》1929,29(1):744-745
Ohne Zusammenfassung 相似文献
960.
In this note we in the spirit of [1], we give ta structure theorem for a graded ring of modular forms related to the orthogonal group O(2, 5). Our results generalize some results obtained by Klöcker in his Ph.D thesis. 相似文献