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991.
992.
Karl A. G. Meyer 《Colloid and polymer science》1943,106(3):212-214
Zusammenfassung Die angeführten theoretischen Berechnungen werden durch Versuche über die Raumerfüllung von Kugelpackungen im begrenzten Raum
bei kleiner werdenden Kugelradien geprüft. 相似文献
993.
C. Meyer W. Harneit B. Naydenov K. Lips A. Weidinger 《Applied magnetic resonance》2004,27(1-2):123-132
Due to their long electron spin relaxation times, the endohedral fullerenes N@C60 and P@C60 are good candidates for the implementation of qubits in an electron spin quantum computer. A central operation in this context is the rotation of the spin direction by an arbitrary angle. In the present experiment, this nutation behavior was studied in pulsed electron spin resonance measurements. We show that, even at room temperature, about 50 Rabi oscillations (about 100 qubit operations) can be performed without refocusing the spin system, although inhomogeneities are present. A special feature of the group V endohedral fullerenes is the electron spinS=3/2, which complicates the nutation behavior. The zero-field splitting at low temperature gives rise to different nutation frequencies for the (1/2,?1/2) transition and the (±3/2, ±1/2) transitions. The frequency ratio is 2/31/2. 相似文献
994.
Ohne Zusammenfassung 相似文献
995.
The evolution of flame surface area and rate of CH layer extinction are measured during the interaction of a two-phase counterflow diffusion flame with fuel-side vortices of varying size and strength. Planar laser-induced fluorescence (PLIF) of CH is used to mark the flame front and particle-image velocimetry (PIV) is used to measure the strain rate field at various phases of the interaction process. Vortices of similar initial circulation but differing in size showed widely disparate peak strain rates and CH decay rates because of varying levels of flame-induced vortex dissipation. Vortex size is also found to have a significant effect on flame surface area evolution during and after extinction, with the presence of droplets playing a significant role in the latter. Implications of these results for the fundamental understanding of vortex–flame interactions are discussed. 相似文献
996.
997.
998.
Convex underestimators of nonconvex functions, frequently used in deterministic global optimization algorithms, strongly influence their rate of convergence and computational efficiency. A good convex underestimator is as tight as possible and introduces a minimal number of new variables and constraints. Multilinear monomials over a coordinate aligned hyper-rectangular domain are known to have polyhedral convex envelopes which may be represented by a finite number of facet inducing inequalities. This paper describes explicit expressions defining the facets of the convex and concave envelopes of trilinear monomials over a box domain with bounds of opposite signs for at least one variable. It is shown that the previously used approximations based on the recursive use of the bilinear construction rarely yield the convex envelope itself. 相似文献
999.
1000.
The nilsson-potential parameters for neutrons at A≃-100 and new deformation values for103Mo and105Mo
T. Seo H. Lawin G. Lhersonneau R. A. Meyer G. Menzen K. Sistemich 《Zeitschrift für Physik A Hadrons and Nuclei》1985,320(3):393-398
The half-lives of the first excited levels in odd-neutron nuclei103Mo and105Mo have been measured. From these data, values of the deformation parameter of?=0.31±0.05 and 0.29±0.06 for103Mo and105Mo, respectively, have been deduced assuming prolate spheroidal shapes. The present results in combination with previously determined properties of the ground-state bands of these nuclei are used to determineμ, the magnitude of the coefficient of the 12 term, in the Nilsson Hamiltonian, for the new region of deformation atA~-100. 相似文献