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111.
112.
Storsberg J Yao ML Ocal N de Meijere A Adam AE Kaufmann DE 《Chemical communications (Cambridge, England)》2005,(45):5665-5666
The first example of a pi,sigma domino-Heck reaction under concomitant rearrangement of the tetracyclic allylcyclopropane endo,exo-bishomobarrelene (5) is reported; the stereoselective reaction proceeds via an intramolecular insertion of a primarily-formed carbopalladation intermediate into a strained cyclopropane C-C sigma-bond, giving 9. 相似文献
113.
J. Kaufmann J. Kronenbitter A. Schwenk 《Zeitschrift für Physik A Hadrons and Nuclei》1975,274(2):87-90
The spin-lattice relaxation timesT 1 of the NMR signals of95Mo and97Mo in aqueous K2MoO4 solutions were determined by the inversion recovery technique. To separate the relaxation rates due to electric quadrupole interaction and due to magnetic dipole interaction, pure H2O and mixtures of H2O and D2O were used as solvent. No dependence of the ratio of the relaxation ratesT 1(95Mo)/T 1(97Mo) on the composition of the solvent was to be detected, i.e. the relaxation due to magnetic dipole interaction may be neglected. From the ratio of the relaxation rates the absolute value of the ratio of the quadrupole moments of the molybdenum isotopes was evaluated: ¦Q(97Mo)/Q(95Mo)¦ = 11.4 ±0.3. 相似文献
114.
D. S. Baranov N. Y. Chabrov V. A. Filipov A. A. Ivanilov P. V. Ivanov V. I. Konyushko V. M. Korablev V. A. Korotkov V. A. Krupnov V. V. Makeev A. G. Myagkov A. Yu. Polyarush A. A. Sokolov E. P. Kuznetsov H. -J. Grabosch H. H. Kaufmann U. Krecker R. Nahnhauer S. Nowak H. Vogt 《Zeitschrift fur Physik C Particles and Fields》1984,21(3):189-196
We present data on the multiplicity structure of inclusive charged hadron production in charged current neutrino and antineutrino freon interactions in the energy range 3–30 GeV resulting from an experiment with the bubble chamber SKAT. Average multiplicities, dispersions and correlation coefficients are investigated. Furthermore, KNO-scaling is studied and average net charges are calculated in different kinematical regions. Our data are compared with results from \(\begin{array}{*{20}c} {( - )} \\ v \\ \end{array} \) -interactions on an isoscalar target of “free” nucleons to study the influence of nuclear effects. 相似文献
115.
Patrizio Angelini Fabrizio Frati Michael Kaufmann 《Discrete and Computational Geometry》2011,45(1):88-140
We show that every c-planar clustered graph has a straight-line c-planar drawing in which each cluster is represented by an axis-parallel rectangle, thus solving a problem posed by Eades, Feng, Lin, and Nagamochi (Algorithmica 44(1):1–32, 2006). 相似文献
116.
For a bounded domain Ω in , N?2, satisfying a weak regularity condition, we study existence of positive and T-periodic weak solutions for the periodic parabolic problem Luλ=λg(x,t,uλ) in , uλ=0 on . We characterize the set of positive eigenvalues with positive eigenfunctions associated, under the assumptions that g is a Caratheodory function such that ξ→g(x,t,ξ)/ξ is nonincreasing in (0,∞) a.e. satisfying some integrability conditions in (x,t) and
117.
Abstract— Ultraweak light emission and light piping of cucumber seedlings was shown using two-dimensional photon imaging via an ultrahigh sensitive photon counting image acquisition system. A macroscopic localization of the photon generating region was achieved. 相似文献
118.
By analysing recent elastic scattering data of 44 MeV/u 40Ar on 60Ni, 120Sn and 208Pb we demonstrate the validity of a semiclassical approximation using complex trajectories in this new energy range. Contrary to an analysis with a quantal code the use of trajectories gives direct information about the sensitivity range of the nuclear potential by looking at the turning point of the most deeply penetrating trajectory. 相似文献
119.
The fluorination of a number of alkyl- and arylchloro- and bromoboranes succeeds upon transhalogenation with lithium or potassium fluoride under mild reaction conditions in good yields. 相似文献
120.
Accuracy and sensitivity of a hole drilling and digital speckle pattern interferometry combined technique to measure residual stresses 总被引:4,自引:2,他引:2
This paper reports on the accuracy and sensitivity of digital speckle pattern interferometry (DSPI) when it is combined with the hole drilling technique for measuring residual stresses. The in-plane displacement field generated by the introduction of a small hole is determined using an automated data analysis approach. This method is based on the calculation of the optical phase distribution through a phase-shifting method and the application of a robust iterative phase unwrapping algorithm. It is experimentally demonstrated that residual stresses can be measured with a relative uncertainty of 7.5%. It is also shown that the minimum value of residual stress that can be determined with the DSPI and hole drilling combined technique is about 10% of the yield stress of the material. 相似文献