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81.
Johannes ZagermannAnthony Deally Nils Metzler-NolteHelge Müller-Bunz Denise WallisMatthias Tacke 《Polyhedron》2011,30(14):2387-2390
An alkyne-substituted fulvene was transformed via hydridolithiation followed by transmetallation with titanium tetrachloride into bis-[p-(prop-2-ynyloxy)-benzyl-cyclopentadienyl] titanium(IV) dichloride. Single crystals of this titanocene derivative could be obtained and the structure determined by X-ray diffraction. It showed that this compound crystallises in the space group C2/c with four molecules in the monoclinic cell. The alkyne-substituted titanocene dichloride derivative was then subject to a copper-catalysed azide-alkyne cycloaddition with its azide-functionalised methylester-protected phenylalanine reaction partner in order to form a linking triazole. This reaction was performed under anhydrous conditions employing a dichloromethane/acetonitrile solvent mixture with copper(I) iodide and 2,6-lutidine as the catalyst system. Under these conditions the adduct between the protein mimic and the titanocene was formed without hydrolysing the titanium dichloride moiety. 相似文献
82.
83.
84.
Nils Ackermann 《Journal of Functional Analysis》2006,234(2):277-320
In an abstract setting we prove a nonlinear superposition principle for zeros of equivariant vector fields that are asymptotically additive in a well-defined sense. This result is used to obtain multibump solutions for two basic types of periodic stationary Schrödinger equations with superlinear nonlinearity. The nonlinear term may be of convolution type. If the superquadratic term in the energy functional is convex, our results also apply in certain cases if 0 is in a gap of the spectrum of the Schrödinger operator. 相似文献
85.
Nils A. Reinke 《Optics Communications》2006,266(1):191-197
Display and illumination technology require light sources with angular independent emission behaviour. Conversely, a strongly angular dependent spectral emission can be desirable for other applications in information technology or spectroscopy. In order to elucidate the potential of organic light-emitting devices (OLEDs) for the latter fields, we performed experimental and numerical studies of the angular dependent emission characteristics of cavity like OLEDs. The light generated in the organic multilayer structure and guided in leaky modes was coupled out by a prism. Here, a semitransparent gold anode, acting as a hole injection layer, was used to enhance the coupling of leaky modes guided inside the OLED to external modes (Kretschmann configuration). The observed light emission was strongly angle dependent, with the spectral emission peak of the device shifting from a wavelength of 680 nm to 500 nm as the angle is varied between 20° and 70° with respect to the normal of the substrate plane. Also, the emitted light shows a high degree of polarization. The observed behaviour can be predicted quantitatively by simulations, which are based on the transfer matrix formalism. 相似文献
86.
87.
Nils R Scheithauer 《Journal of Algebra》1998,200(2):419
We construct Lie algebras from vertex superalgebras and study their structure. They are sometimes generalized Kac–Moody algebras. In some special cases we can calculate the multiplicities of the roots. 相似文献
88.
Nils Byrial Andersen 《Journal of Mathematical Analysis and Applications》2003,288(1):124-135
We prove real Paley-Wiener theorems for the (inverse) Jacobi transform, characterising the space of L2-functions whose image under the Jacobi transform are (smooth) functions with compact support. 相似文献
89.
The acylated guanine-glyoxal adduct (I) has been alkylated with 4-bromobutyl acetate and in the presence of sodium hydride the reaction was regioselective to give 7-alkylguanine. 相似文献
90.
Richard L. Liboff Nils Weimann Mason A. Porter 《International Journal of Theoretical Physics》2002,41(7):1389-1395
We construct a prime symmetry relation for integers that is equivalent to Goldbach's conjecture and show that numerical computations of this prime symmetry property strongly resemble a chaotic sequence. We define and examine the notions of global and local prime quasientropies. Finally, we employ the fact that the prime number sequence satisfies the property of deterministic randomness to consider its utility for the field of quantum computation. 相似文献