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111.
An X-ray topographic method utilizing non-parallel (+,-) setting for measuring lattice mismatches between epitaxial films and substrates is reported. This method gives quantitative as well as topographical information on lattice distortions in a distorted crystal and allows us to study any reflection from various crystals, in which the fractional variation of lattice spacing, δd/d, is of the order of 10-4?10-5. Examples of applications are lattice mismatches between epitaxial magnetic garnet films and (111) gadolinium garnet (GGG) substrates. The spacing of the epitaxial film was slightly larger along the [111] direction than that of the substrate and the apparent crystal symmetry of the epitaxial film is rhombohedral. 相似文献
112.
An auto-ranging circuit which accommodates the erratic nature of the electrometer output signals from a spark-source mass-spectrometer is described briefly. 相似文献
113.
Chloro[N-3′5′-η-(4′-methylpentenyl)quinoline-2]palladium was synthesized; the NMR-spectrum of this compound is helpful in distinguishing the cis/trans-isomers of other non-bridged π-allyl-base-palladium chloride complexes. 相似文献
114.
I.J. Galpin F.E. Hancock B.K. Handa A.G. Jackson G.W. Kenner R. Ramage B. Singh R.G. Tyson 《Tetrahedron》1979,35(23):2779-2783
The fully protected 17–26 fragment of a lysozyme analogue has been synthesised. A fragment condensation approach has been employed using the protected subfragments 17–19, 20–22 and 23–26. In the synthesis of the subfragments the use of the diphenylphosphinyl mixed anhydride method has been demonstrated. 相似文献
115.
Tien-Sung Lin Michael K. Bowman James R. Norris Gerhard L. Closs 《Chemical physics letters》1981,78(2):283-286
ENDOR frequencies of randomly oriented triplets have been measured from the fast Fourier transform of electron spin echo envelope modulation. Important experimental conditions are low temperatures, high microwave power and long phase memory time in a proper form of solvent. The technique is exemplified by using diphenylmethylenes in rigid glasses, polycrystalline forms and single crystals of benzophenones. 相似文献
116.
J.W. Gadzuk 《Chemical physics letters》1981,80(1):5-10
The vibrational spectrum of an atom or molecule adsorbed on a metallic surface is influenced by the dynamic interaction between the localized oscillator and the continuum of electron-hole pair excitations in the solid. Features of an exactly soluble model for this interacting system are presented, the local spectral function is obtained in terms of calculable level shift and broadening functions, and some prototypical numerical results are displayed and discussed. 相似文献
117.
118.
A general quadratic force field is determined for the out-of-plane vibrations of florobenzenes. The force constants for the out-of-plane wagging of both CH and CF bonds decrease by about 10 % for each ortho fluorine substituent. No significant meta dependence could be detected. It is shown that the present field is in excellent accord with the chlorobenzene field of Scherer and with the benzene fields of Whiffen and of Kydd when due allowance is made for differences in coordinate definitions. 相似文献
119.
Fluorescence lifetimes and fluorescence quenching rates are reported for several vibronic levels in the A2Πu electronic manifold of BO2. The relationship of these results to earlier Hanle-effect measurements is discussed. 相似文献
120.