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21.
G. W. Englert 《Applied Scientific Research》1972,25(1):201-214
A model of the random walk is formulated to allow a simple computing procedure to replace the difficult problem of solution
of the Fokker-Planck equation. The step sizes and probabilities of taking steps in the various directions are expressed in
terms of Fokker-Planck coefficients. Application is made to many particle systems with Coulomb interactions. The relaxation
of a highly peaked velocity distribution of particles to equilibrium conditions is illustrated.
Part I of a thesis submitted in partial fulfillment of Doctor of Philosophy requirements at Colorado State University. 相似文献
22.
The adsorption of CO and O on Ni (111) was studied by low-energy ion scattering (ISS) and low-energy electron diffraction (LEED). For the ordered (√7/2) × (√7/2) R19.1° CO layer ion scattering gives a coverage greater than monolayer, and for the (2 × 2) O layer a coverage of monolayer. The CO is non-dissociatively adsorbed, with the C bound to the Ni. The molecules are oriented parallel to the surface normal. Island formation at lower CO coverages is possible. 相似文献
23.
The three methoxycarbonyl-substituted quadricyclanones 7a , 7b and 7c have been synthesized in good to excellent yields. Some of their physical (UV., NMR.) and chemical properties (e.g. condensation and pyrolysis reactions) are discussed. 相似文献
24.
Reinterpretation of the pioneering work of Nielsen and Olesen and others on magnetic confinement in (electric) superconductors leads to simple models which exhibit electric confinement of the type hoped for in quantum chromodynamics. “Electric” flux tubes joining “quarks” arise at a semi-classical level as a result of the existence of (pseudo) particles. The theory can be described in terms of a classical action principle only upon suitable modification of the action; this modification has profound topological significance as it is intimately related to the quantization condition for (pseudo) particles. 相似文献
25.
McGuinness DS Wasserscheid P Keim W Morgan D Dixon JT Bollmann A Maumela H Hess F Englert U 《Journal of the American Chemical Society》2003,125(18):5272-5273
Cr(III) complexes of tridentate SNS ligands have been prepared and evaluated as catalysts for ethylene trimerization, with several giving very high activity and excellent selectivity toward 1-hexene when activated with methylaluminoxane. The new complexes illustrate the potential of sulfur-based ligands on early transition metals for catalysis. 相似文献
26.
27.
State tomography on qubit pairs is routinely carried out by measuring the two qubits separately, while one expects a higher efficiency from tomography with highly symmetric joint measurements of both qubits. Our numerical study of simulated experiments does not support such expectations. 相似文献
28.
A. Heiduschka und F. Englert 《Fresenius' Journal of Analytical Chemistry》1921,60(5-6):161-166
Ohne Zusammenfassung 相似文献
29.
30.
Silver meso- and rac-tartrate and silver squarate have been synthesized, and the crystal structure of a new polymorph of the latter is reported.
Three reaction products of these silver salts with pyrazine have been obtained and structurally characterized: From silver
squarate, a chain polymer with linear coordination of Ag(I) by two pyrazine ligands is formed, whereas the silver tartrates
yield solids in which the inner coordination sites around the metal are only partially occupied by N donors; in contrast to
expectation, oxygen coordination prevails. All the four new Ag(I) coordination compounds reported show high packing coefficients
in the range between 0.789 and 0.885. In order to put these results into a meaningful context, packing coefficients for the
crystal structures of almost 30,000 compounds retrieved from the Cambridge Structural Database have been determined. Tartrates
pack significantly closer than pyrazine complexes or metal-containing compounds in general. The exceptionally high packing
coefficient of the new polymorph of silver squarate is due to stacking of anions and concomitant Ag···Ag contacts, both along
the shortest lattice parameter which amounts to only 3.3990(9) ?. 相似文献