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991.
Attila Vértes Ilona Czakó-Nagy Philip Deck Henry Leidheiser Jr. 《Hyperfine Interactions》1988,41(1):729-732
The emission Mössbauer technique is used to study the chemical structure of the interphase formed between a cobalt substrate and a polyimide coating. The results are interpreted to indicate that the coating is bonded to the cobalt substrate by means of carboxylate bonds with Co2+ ions in the oxide film at the interface. 相似文献
992.
993.
George A. Baker Jr. 《Journal of statistical physics》2003,110(3-6):971-979
We examine the intuitive, classical idea that an interactive system involving commonly used attractive potentials should always have a pressure which is less than that of an ideal Fermi gas. We find that quantum effects are of crucial importance and that, while this idea is normally correct, under certain circumstances, the pressure can exceed that of the ideal Fermi gas. 相似文献
994.
C. M. Johnson Jr. T. L. Rucker M. A. Smith E. L. Tan 《Journal of Radioanalytical and Nuclear Chemistry》1995,192(2):339-344
Neutron activation analysis data quality must be validated to serve evidentiary purposes for environmental restoration and health protection projects. This paper gives a basis for determining the technical validity of neutron activation analysis data. 相似文献
995.
S Clark Ligon Jr. 《Journal of fluorine chemistry》2003,123(1):139-146
4-Bromotrifluorovinyloxybenzene (4-Br-TFVE) undergoes cyclodimerization upon heating at 150 °C affording cis and trans isomers of 1,2-bis(4-bromophenoxy)hexafluorocylcobutane. Stereoisomers were separated by selective crystallization, confirmed by single crystal X-ray, and further characterized by NMR. Remarkable difference in the solid state structures include aryl to aryl dihedral angles of 12° for the trans isomer and 88° for the cis isomer. Polymers containing roughly equal amounts of cis and trans fused perfluorocyclobutyl (PFCB) rings should be expected to have low crystallinity due to the marked difference in the two unit cells as is observed. 相似文献
996.
The heats of formation of the trifluoromethanol (CF3OH) and carbonic difluoride (CF2O) molecules are calculated with theoretical methods of demonstrated high accuracy. The results are used to assess the accuracy of the reported value of the heat of formation of CF2O and to provide an accurate estimate for CF3OH. The implications of these results for atmospheric chemistry are discussed. 相似文献
997.
998.
P. H. Dionisio A. Vasquez B. Hallouche D. H. Mosca Jr. S. R. Teixeira W. H. Schreiner 《Hyperfine Interactions》1991,67(1-4):493-499
The composition, structure, magnetic properties and stability of iron-tin thin films produced by co-evaporation with de magnetron sputtering are studied. Rutherford backscattering. Auger electron spectroscopy. X-ray diffraction and conversion electron Mössbauer spectroscopy indicate the formation of a homogeneous solid solution of tin in iron with a concentration well above the limit of equilibrium solid solubility. Measurements with a vibrating-sample magnetometer show that the films present saturation magnetization and remanence similar to those of pure iron, but a much smaller coercivity. Thermal treatment or aging lead to second-phase precipitation, which is accompanied by a growth of coercivity and remanence. 相似文献
999.
1000.
J. M. Wouters R. H. Kraus Jr. D. J. Vieira G. W. Butler K. E. G. Löbner 《Zeitschrift für Physik A Hadrons and Nuclei》1988,331(3):229-233
The direct mass measurements of the neutron-rich nuclei11Li,14Be,17B,19–20C,20–22N,23–24O, and25–27F have been performed using the Time-of-Flight Isochronous (TOFI) spectrometer. We observe a notable drop in the two-neutron separation energies for the oxygen and fluorine isotopes afterN=15. This behavior is interpreted using the shell model. 相似文献