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21.
C. M. Lerner Y. P. Ma J. S. Brooks R. Messervey P. Tedrow 《Applied Physics A: Materials Science & Processing》1991,52(6):433-437
The longitudinal and transverse magnetoresistance to fields of 19 Tesla and 4.2 K has been measured for bismuth films ranging in thickness from 0.01 to 2 m. We have observed a pronounced maximum in the longitudinal magnetoresistance which is thickness dependent. We compare these results with classical size effect theories for the longitudinal magnetoresistance in terms of magnetic-field-dependent electron scattering at grain and film boundaries. Measurements of the longitudinal magnetoresistance to 38 Tesla show a quenching of the classical size effect in the high field limit. This result strongly supports our analysis.Work supported by NSF grant #DMR 8113456Supported by the National Science Foundation 相似文献
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Lozhkomoev A. S. Bakina O. V. Glazkova E. A. Svarovskaya N. V. Lerner M. I. 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2018,92(12):2530-2534
Russian Journal of Physical Chemistry A - Porous composites of different phase composition are synthesized via oxidation in a water–ethanol mixture of bimetallic Al/Zn nanoparticles obtained... 相似文献
24.
Wei Xu Dr. Karoly Kozma Tianxiang Sha Yi-Jen Wu Prof. May Nyman Prof. Michael M. Lerner 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(36):8101-8104
The alkaline earth metals (M=Mg, Ca, Sr, and Ba) exhibit a +2 oxidation state in nearly all known stable compounds, but MI dimeric complexes with M−M bonding, [M2(en)2]2+, (en=ethylenediamine) of all these metals can be stabilized within the galleries of donor-type graphite intercalation compounds (GICs). These metals can also form GICs with more conventional metal (II) ion complexes, [M(en)2]2+. Here, the facile interconversion between dimeric-MI and monomeric-MII intercalates upon the addition/removal of en are reported. Thermogravimetry, powder X-ray diffraction, and pair distribution function analysis of total scattering data support the presence of either [M2(en)2]2+ or [M(en)2]2+ guests. This phase conversion requires coupling graphene and metal redox centers, with associated reversible M−M bond formation within graphene galleries. This chemistry allows the facile isolation of unusual oxidation states, reveals M0→M2+ reaction pathways, and present new opportunities in the design of hybrid conversion/intercalation materials for applications such as charge storage. 相似文献
25.
M. Sc. Timo Trageser Dr. Michael Bolte Dr. Hans-Wolfram Lerner Prof. Dr. Matthias Wagner 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(20):7800-7805
The tetraaryl μ-hydridodiborane(4) anion [ 2 H]− possesses nucleophilic B−B and B−H bonds. Treatment of K[ 2 H] with the electrophilic 9-H-9-borafluorene (HBFlu) furnishes the B3 cluster K[ 3 ], with a triangular boron core linked through two BHB two-electron, three-center bonds and one electron-precise B−B bond, reminiscent of the prominent [B3H8]− anion. Upon heating or prolonged stirring at room temperature, K[ 3 ] rearranges to a slightly more stable isomer K[ 3 a ]. The reaction of M[ 2 H] (M+=Li+, K+) with MeI or Me3SiCl leads to equimolar amounts of 9-R-9-borafluorene and HBFlu (R=Me or Me3Si). Thus, [ 2 H]− behaves as a masked [:BFlu]− nucleophile. The HBFlu by-product was used in situ to establish a tandem substitution-hydroboration reaction: a 1:1 mixture of M[ 2 H] and allyl bromide gave the 1,3-propylene-linked ditopic 9-borafluorene 5 as sole product. M[ 2 H] also participates in unprecedented [4+1] cycloadditions with dienes to furnish dialkyl diaryl spiroborates, M[R2BFlu]. 相似文献
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Svarovskaya N. V. Bakina O. V. Pervikov A. V. Rubtsov K. V. Lerner M. I. 《Russian Physics Journal》2020,62(9):1580-1586
Russian Physics Journal - Using a simultaneous electrical explosion of two twisted wires, bimetallic Ti–Ag and Fe–Ag nanoparticles are synthesized, where the component ratios are... 相似文献
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The possibility of the two-dimensional electron crystallization in the strong magnetic field is discussed by comparison between electron free energies in liquid and crystal states. The electron free energy in the liquid state is determined in Hartree-Fock approximation, while the correlation phenomena are proved to be negligible. The electron free energy in the crystal state is calculated in the harmonic approximation. The magnetic field is shown to “nonmonotonously” affect the crystal formation. From one hand, an electron crystal may exist in an interval of the strong magnetic field H at rather high density, where that is impossible at H=0. From the other hand, at any density the sufficiently strong field forces electron lattice to melt at finite temperature. 相似文献
29.
NMR linewidths and magnetic susceptibilities of 3He adsorbed on Grafoil have been measured by a continuous wave technique between 0.40 K to 4.21 K for five fractional monolayer coverages, x, between 0.20 and 0.96. Interpretations in terms of the phases of the submonolayers are presented. 相似文献
30.
L. Lerner 《Zeitschrift fur Physik C Particles and Fields》1990,46(3):489-506
The calculation of hadron distributions ine + e ?→4-jets using the 4-parton matrix element diverges unless cuts are imposed on the parton phase space. Experimentally cuts can be applied only on the hadron spectrum and not at the 4-parton level. Test observables for the three gluon vertex relying on jet-jet angular correlations are found to be particularly sensitive to these parton cuts. The contribution from the parton phase space below the cut region is calculated to modified logarithmic approximation accuracy using a Monte Carlo simulator HERWIG and is found to be of order 45%. This modifies the predictions of the tests so that differences between QCD and ‘QED’ are diminished significantly. A tagging method based on the average energy of particles in a jet is found to be best at identifying both gluon jets with a possible 9:1 success to failure ratio and it allows the presence of the three gluon vertex to be verified. 相似文献