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991.
992.
H. Busch G. Jakob K. -H. Speidel J. Cub S. Kremeyer U. Grabowy A. Gohla J. Gerber A. Meens P. Maier-Komor C. Rezny M. Schulz P. Padberg 《Zeitschrift für Physik A Hadrons and Nuclei》1996,355(1):9-15
Measurements of transient magnetic fields (TF) were performed on swift heavy ions of56Fe and80Se, with Coulomb excitation of their first 2+ state as probe, traversing thin Fe layers with segmented and unsegmented structures. The 50 µm×50 µm squares of the segments were accomplished applying the techniques of photolithography and ion etching. The magnitude of the TF deduced clearly shows that by segmentation of the targets the ion beam induced attentuations can be eliminated. This finding has direct applications tog-factor measurements. 相似文献
993.
The Landauer-Büttiker approach is used to describe electron transport along a chain of scatterers which allow elastic as well as inelastic processes. The inelastic scattering takes place via side branches coupling the chain to electron reservoirs which serve as a heat bath. For small inelastic coupling of the scatterers to the heat bath strong interference effects lead to spatial fluctuations of the charge density. The corresponding oscillations of the chemical potential are discussed in view of phase-sensitive experiments measuring the four-probe resistance. 相似文献
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Riaz Ahmed Fred G. Schreiber Robert Stevenson John R. Williams Hilary M. Yeo 《Tetrahedron》1976,32(12):1339-1344
The phenolic coupling of halogen-containing ferulic acid and methyl ester derivatives was examined with particular reference to the synthesis of lignans of the aryltetralin and tetrahydrofuran classes. (±)-Isolariciresinol dimethyl ether (18) and (±)-veraguensin (27) have been synthesized. 相似文献
999.
Frequency map of the spiral ganglion in the cat 总被引:1,自引:0,他引:1
A frequency map of the cat spiral ganglion has been determined on the basis of reconstructed cochleas in which individual spiral ganglion cells were labeled with horseradish peroxidase following determination of their characteristic frequency; the cochleas were the same as those used by Liberman and Oliver [J. Comp. Neurol. 223, 163-176 (1984)]. By matching this map to one previously described for the organ of Corti [M. C. Liberman, J. Acoust. Soc. Am. 72, 1441-1449 (1982)], an estimate of the afferent innervation density of the inner hair cells was derived. Counts of myelinated nerve fibers at the habenula perforata and inner hair cells were also performed and yielded similar results in all but the most basal 10%-15% of the cochlea. Between 0.1 and 20 kHz there is a gradual monotonic increase as a function of frequency in the number of spiral ganglion cells terminating on each inner hair cell, from about eight ganglion cells per inner hair cell to about 30 ganglion cells per inner hair cell. Above 20 kHz, it seems there is a decrease to about ten ganglion cells per inner hair cell. The greatest innervation density is at approximately the region of the basilar membrane with the greatest density of inner hair cells per millimeter. 相似文献
1000.
Some balanced complete block designs 总被引:1,自引:0,他引:1
Shmuel Schreiber 《Israel Journal of Mathematics》1974,18(1):31-37
Letq=6t±1, ν=2q+2. The (ν/3) tri ples on ν marks may be partitioned intoq sets, each forming a BIBD of parameters (ν,3,2). Related results, some of them known, are also discussed briefly. 相似文献