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81.
A. Beckmann K. D. Böklen G. Bremer D. Elke 《Zeitschrift für Physik A Hadrons and Nuclei》1975,272(2):143-145
Using the atomic beam magnetic resonance method the Zeeman interactions of12C in the3 P 1 and3 P 2 states at magnetic fields of about 3.4 kOe have been measured. The measured quantities areg J (3 P 1)?gJ(3 P 2)=15.4(1.0)·10?6 g J (3 P 2)=1.5010616 (50), from which the following value for gJ(3P1) can be calculated:g J (3 P 1)=1.5010770 (50). The experimental results are in moderate agreement with theoretical calculations. 相似文献
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85.
We report on the experimental demonstration of the internal bosonic Josephson effect in a rubidium spinor Bose-Einstein condensate. The measurement of the full time dynamics in phase space allows the characterization of the theoretically predicted π-phase modes and quantitatively confirms analytical predictions, revealing a classical bifurcation. Our results suggest that this system is a model system which can be tuned from classical to the quantum regime and thus is an important step towards the experimental investigation of entanglement generation close to critical points. 相似文献
86.
A polygon in ${{\mathbb R}^2}$ is called self-affine if it can be dissected into k ≥ 2 affine images of itself. Self-affine convex polygons have at most five vertices. Triangles are trivially self-affine. It is shown that every convex quadrangle is self-affine, whereas only some, but not all convex pentagons are self-affine. 相似文献
87.
T. E. Golikova F. Hübler D. Beckmann N. V. Klenov S. V. Bakurskiy M. Yu. Kupriyanov I. E. Batov V. V. Ryazanov 《JETP Letters》2013,96(10):668-673
Specific features of the proximity effect and Josephson behavior of submicron planar SNS junctions fabricated by electron beam lithography and shadow evaporation have been studied experimentally and theoretically. The critical current of the junctions has been found to drastically increase with a decrease in temperature, which is associated with a change in the effective size of the weak link owing to the additional SN interface. 相似文献
88.
G. Dersch R. Beckmann G. Feige T. Lund P. Vater R. Brandt 《Isotopes in environmental and health studies》2013,49(6):303-304
A recent article interpreted the experiment by Dersch et al. on the formation of 24Na in 40Ar + Cu interactions in a very simple manner. The results from emulsion experiments performed with 3.6 AGeV 22Ne were adapted for the interpretation of the experiments with 1.8 AGeV 40Ar. The model used the same mean value for the energy of minimum ionizing protons and pions at all angles. It is argued that a more complex approach is needed for a satisfactory interpretation. 相似文献
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90.
Philipp Niermeier Sebastian Blomeyer Younes K. J. Bejaoui J. Louis Beckmann Beate Neumann Hans‐Georg Stammler Norbert W. Mitzel 《Angewandte Chemie (International ed. in English)》2019,58(7):1965-1969
Bidentate boron Lewis acids based on 1,8‐diethynylanthracene were synthesised in two steps by initial stannylation of the terminal alkynes and subsequent tin–boron exchange with different chloroboranes. The reactions were very selective, and the target compounds were obtained in high purity and good to excellent yields. Complexation experiments of 1,8‐bis[(diphenylboranyl)ethynyl]anthracene with nitrogen bases (pyridine, pyrimidine, TMEDA) afforded three stable adducts, which were structurally characterised by X‐ray diffraction. Competition experiments demonstrated the selective exchange of guests, and quantum‐chemical calculations provided information on their energetics. NMR experiments at low temperature gave insight into the dynamic behaviour of the TMEDA adduct. 相似文献