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991.
992.
John N. Helbert Edward H. Poindexter Burkhard E. Wagner 《Chemical physics letters》1977,52(3):546-548
Strongly scalar 1H intermolecular dynamic nuclear polarization (DNP) of solvent 1H nuclei in solutions of organic free radicals has now been observed at room temperature. Transient protonation of the CF3COOH/pyridyl imidazoline-1-oxyl radical system accounts for the observed effects. 相似文献
993.
994.
Let denote the set of all n × n Hadamard matrices. For , define the weight of H to be w(H) = number of 1's in H, and . In this paper, we derive upper and lower bounds for w(n). 相似文献
995.
S. Louis Hakimi Edward F. Schmeichel 《Journal of Algorithms in Cognition, Informatics and Logic》1984,5(4):526-530
Consider a system of n units, at most t of which are faulty. An adaptive diagnosis algorithm is presented which uses a sequence of tests to identify a fault-free unit. The algorithm requires at most 2t − ν(t) tests, where ν(t) is the number of 1's in the binary representation of t. Moreover, many of the tests can be performed simultaneously. The previously best algorithms for the same purpose required 2t − 1 tests, none of which could be performed simultaneously. 相似文献
996.
997.
J. A. Hermann J. N. Elgin P. L. Knight 《Zeitschrift für Physik B Condensed Matter》1982,45(3):255-258
We show that bistable behaviour in a two-photon resonant system within a cavity may be attributed to interactive mode-pulling via the two-photon optical Kerr effect and also to absorptive bleaching (atomic saturation). The interactive Kerr process may be regarded as giving rise to a new category of optical bistability. Moreover, a mechanism for the recently-predicted tristability can be found in terms of simultaneous competition between the interactive Kerr effect and bleaching. 相似文献
998.
999.
1000.
Edward R. Hogan 《Historia Mathematica》1981,8(4):439-455
Theodore Strong was a prolific contributor to the mathematical and scientific journals of ante-bellum America. His work was not remarkable in its originality, but it dealt with mathematics that was quite sophisticated for its time and place. Strong's published work was a significant factor in the dissemination of advanced mathematics to his countrymen, and he played an important role in the education of a few mathematicians who were active in the latter part of the 19th century, most notably George William Hill. 相似文献