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161.
Pavle V.M. Blagojevi? Benjamin Matschke Günter M. Ziegler 《Topology and its Applications》2011,158(12):1445-1452
We prove that any continuous map of an N-dimensional simplex ΔN with colored vertices to a d-dimensional manifold M must map r points from disjoint rainbow faces of ΔN to the same point in M: For this we have to assume that N?(r−1)(d+1), no r vertices of ΔN get the same color, and our proof needs that r is a prime. A face of ΔN is a rainbow face if all vertices have different colors.This result is an extension of our recent “new colored Tverberg theorem”, the special case of M=Rd. It is also a generalization of Volovikov?s 1996 topological Tverberg theorem for maps to manifolds, which arises when all color classes have size 1 (i.e., without color constraints); for this special case Volovikov?s proof, as well as ours, works when r is a prime power. 相似文献
162.
We consider biquadratic number fields whose maximal orders have power integral bases consisting of units. We prove an effective
and efficient criteria to decide whether the maximal order of a biquadratic field has a unit power integral basis or not.
In particular we can determine all trivial biquadratic fields whose maximal orders have a unit power integral basis. 相似文献
163.
Nickel N-confused tetraphenylporphyrin, 1, and nickel 2-N-methyl-N-confused tetraphenylporphyrin, 1-Me, exhibit unusual sign-reversed (positive-to-negative intensities in ascending energy) MCD spectra in the Q-type band region, suggesting a rare ΔHOMO < ΔLUMO relationship between π and π* MOs in the porphyrin core. Simple and reversible deprotonation of the external NH proton in 1 dramatically changes the electronic structure of the porphyrin core into the ΔHOMO > ΔLUMO combination characteristic for the meso-(tetraaryl)porphyrins. DFT, time-dependent DFT, and semiempirical ZINDO/S calculations on 1, 1-Me, and 1(-) confirm the experimental finding and successfully explain the MCD pattern in the target compounds. 相似文献
164.
165.
166.
Thomas Ziegler 《Physik in unserer Zeit》2006,37(5):207-207
167.
K. -H. Schmidt T. Brohm H. -G. Clerc M. Dornik M. Fauerbach H. Geissel A. Grewe E. Hanelt A. Junghans A. Magel W. Morawek G. Münzenberg F. Nickel M. Pfützner C. Scheidenberger K. Sümmerer D. Vieira B. Voss C. Ziegler 《Physics letters. [Part B]》1993,300(4):313-316
Cross sections of iridium and platinum isotopes have been measured, which were produced as fragments from 197Au projectiles interacting with aluminum target nuclei at 1 A GeV. The fragments were identified by a kinematic analysis (ΔE−Bρ-time-of-flight) and by an ion-optical separation at the projectile-fragment separator FRS at GSI. Indications are found for high excitation energies and weak proton-neutron correlations in the peripheral nuclear-collision process. 相似文献
168.
K. Wang C. Steimer D. Wamwangi S. Ziegler M. Wuttig 《Applied Physics A: Materials Science & Processing》2005,80(8):1611-1616
The influence of In doping on the crystallization kinetics of Ge2Sb2Te5 has been investigated using four-point-probe electrical resistance measurements, grazing incidence X-ray diffraction (XRD), X-ray reflectometry (XRR), variable incident angle spectroscopic ellipsometry, a static tester, and atomic force microscopy. For a stoichiometric Ge2Sb2Te5 alloy doped with 3% In, the amorphous-to-crystalline transition is observed at 150 °C in the sheet resistance measurements. XRD reveals the formation of a predominant NaCl-type Ge2Sb2Te5 phase during the amorphous-to-crystalline transition together with small amounts of crystalline In2Te3. Density values of 5.88±0.05 g cm-3 and 6.22±0.05 g cm-3 are measured by XRR for the film in the amorphous and crystalline states, respectively. Perfect erasure can be achieved by laser pulses longer than 165 ns. The retarded crystallization, as compared with the undoped Ge2Sb2Te5 alloy, is attributed to the observed phase segregation. Sufficient optical contrast is exhibited and can be correlated with the large density change upon crystallization. PACS 68.55.-a; 78.20.-e; 78.66.Jg 相似文献
169.
Many families of parametrized Thue equations over number fields have been solved recently. In this paper we consider for the
first time a family of Thue equations over a polynomial ring. In particular, we calculate all solutions of
X(X-Y)(X-(T+x)Y)+Y3=1+xT(1-T)X(X-Y)(X-(T+\xi)Y)+Y^3=1+\xi T(1-T)
over
\Bbb C[T]{\Bbb C}[T]
for all
x ? \Bbb C\xi\in{\Bbb C}
. 相似文献
170.