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41.
42.
We observed the two-dimensional plasmons of the two-component electron plasma in the (001) Si-inversion layer resulting from simultaneous population of the [001] valley, E0, and the [010] valley, E0′, subbands under a compressional uniaxial stress along [010]. Our data show an onset of electron transfer from E0 to E0′ at X = (1.4 ± 0.1) kbar for n = 1.67 × 1012 cm?2 and X = (1.2 ± 0.2) kbar for n = 2.60 × 1012 cm?2, consistent with the theory of Takada and Ando that includes the electron-electron correlation effects. 相似文献
43.
J. Schwinger M. O. Scully B. -G. Englert 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1988,10(2-3):135-144
A Stern-Gerlach interferometer combines Stern-Gerlach deflecting magnets to reconstitute initially split beams, in such a way that an arbitrary initial spin state is recovered. Technical and fundamental limitations on the realizability of the device are derived. 相似文献
44.
Purification and structure of porcine calcitonin-1 总被引:3,自引:0,他引:3
45.
Trace anomalies in a conformal invariant theory do not arise when its conformal invariance in four dimensions is extended to an arbitrary number n of space-time dimensions: the theory can be made finite in any order of perturbation theory by conformal invariant counterterms in n dimensions. Such an extension of conformal invariance is possible provided one works in the framework of spontaneously broken conformal invariance. This is shown explicitly by working out several examples at the one-loop level and by examining the Ward identities which lead to a general proof.We speculate upon possible consequences of these results on the nature of gravitation and other fundamental interactions. 相似文献
46.
Gerhard Englert 《Fresenius' Journal of Analytical Chemistry》1961,181(1):447-455
Ohne Zusammenfassung 相似文献
47.
An additional splitting of Shubnikov-de Haas oscillations in (lll) n-type silicon inversion layers in observed. We attribute it to valley splitting, analogous to that previously observed on (100) surface layers, and point out that theoretical explanations of valley splitting, restricted to the valley configuration in (100) inversion layers, are not applicable. 相似文献
48.
49.
Auvray N Basu Baul TS Braunstein P Croizat P Englert U Herberich GE Welter R 《Dalton transactions (Cambridge, England : 2003)》2006,(24):2950-2958
A comparative study of the reactivity of isolobal rhenium and molybdenum carbonylmetallates containing a borole, in [Re(eta5-C4H4BPh)(CO)3]- (2), a boratanaphthalene, in [Mo(eta5-2,4-MeC9H6BMe)(CO)3]- (4a) and [Mo(eta5-2,4-MeC9H6BNi-Pr2)(CO)3]- (4b), a boratabenzene, in [Mo(eta5-3,5-Me2C5H3BNi-Pr2)(CO)3]- (6) or a dimethylaminocyclopentadienyl ligand, in [Mo(eta5-C5H4NMe2)(CO)3]- (7), toward palladium(II), gold(I), mercury(II) and platinum(II) complexes has allowed an evaluation of the role of these pi-bonded ligands on the structures and unprecedented coordination modes observed in the resulting metal-metal bonded, heterometallic complexes. The new metallate 6 was reacted with [AuCl(PPh3)], and with 1 or 2 equiv. HgCl2, which afforded the new heterodinuclear complexes [Au{Mo(eta5-3,5-Me2C5H3BNi-Pr2)(CO)3}(PPh3)] (Mo-Au) (10) and [Hg{Mo(eta5-3,5-Me2C5H3BNi-Pr2)(CO)3}Cl] (Hg-Mo) (11) and the heterometallic chain complex [Hg{Mo(eta5-3,5-Me2C5H3BNi-Pr2)(CO)3}2] (Mo-Hg-Mo) (12), respectively. Reactions of the new metallate 7 with HgCl2, trans-[PtCl2(CNt-Bu)2] and trans-[PtCl2(NCPh)2] yielded the heterodinuclear complex [Hg{Mo(eta5-C5H4NMe2)(CO)3}Cl] (Mo-Hg) (15), the heterotrinuclear chain complexes trans-[Pt{Mo(eta5-C5H4NMe2)(CO)3}2(CNt-Bu)2] (Mo-Pt-Mo) (16) and trans-[Pt{Mo(eta5-C5H4NMe2)(CO)3}2(NCPh)2] (Mo-Pt-Mo) (17), the mononuclear complex [Mo(eta5-C5H4NMe2)(CO)3Cl] (18), the lozenge-type cluster [Mo2Pt2(eta5-C5H4NMe2)2(CO)8] (19) and the heterodinuclear complex [[upper bond 1 start]Pt{Mo(eta5-C5H4N[upper bond 1 end]Me2)(CO)3}(NCPh)Cl](Mo-Pt) (20), respectively. The complexes 11, 16, 17.2THF, 18 and 20 have been structurally characterized by X-ray diffraction and 20 differs from all other compounds in that the dimethylaminocyclopentadienyl ligand forms a bridge between the metals. 相似文献
50.
Claudia J. Diehl Thomas Scattolin Ulli Englert Franziska Schoenebeck 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(1):217-221
While there is a growing interest in harnessing synergistic effects of more than one metal in catalysis, relatively little is known beyond bimetallic systems. This report describes the straightforward access to an air‐stable Pd trimer and presents unambiguous reactivity data of its privileged capability to differentiate C?I over C?Br bonds in C?C bond formations (arylation and alkylation) of polyhalogenated arenes, which typical Pd0 and PdI‐PdI catalysts fail to deliver. Experimental and computational reactivity data, including the first location of a transition state for bond activation by the trimer, are presented, supporting direct trimer reactivity to be feasible. 相似文献