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971.
Addition of tricyclo[4.2.2.02.5]deca-3,7-diene and iodine azide was found to be syn on the cyclobutene moiety. Structure determination of the adducts and the formation mechanism are discussed. 相似文献
972.
K L Rinehart H H Mathur K Sasaki P K Martin C E Coverdale 《Journal of the American Chemical Society》1968,90(22):6241-6243
973.
Geldanamycin. I. Structure assignment 总被引:1,自引:0,他引:1
K Sasaki K L Rinehart G Slomp M F Grostic E C Olson 《Journal of the American Chemical Society》1970,92(26):7591-7593
974.
975.
Extreme ultraviolet radiation emitted from He plasma has been studied by means of photoelectron energy analyzer. Relative and absolute intensities of Lyman series of ionized helium have been measured. From these spectral intensities, the electron temperature of the plasma has been estimated at several tens of eV. 相似文献
976.
977.
The transverse electroreflectance of GaSe has been measured near the fundamental edge at 4.2 K. The observed structures have been interpreted in terms of the Franz-Keldysh oscillations, the exciton ground state, the first excited state of exciton, and the phonon replica of the exciton ground state. 相似文献
978.
In order to simplify the mass data processing in a response matrix method for gamma-ray spectral analysis, a method using a Fast Fourier Transform devised. The validity of the method was confirmed by a computer simulation for spectra of a NaI detector. The method uses the fact that spectral data can be represented by Fourier series with reduced number of terms. The estimation of intensities of gamma-ray components is performed by a matrix operation using the compressed data of an observation spectrum and standard spectra in Fourier coefficients. The identification of gamma-ray energies is also easy. Several features in the method and a general problem to be solved in a response matrix method are described. 相似文献
979.
980.
De Franceschi S Sasaki S Elzerman JM van der Wiel WG Tarucha S Kouwenhoven LP 《Physical review letters》2001,86(5):878-881
We report transport measurements on a semiconductor quantum dot with a small number of confined electrons. In the Coulomb blockade regime, conduction is dominated by cotunneling processes. These can be either elastic or inelastic, depending on whether they leave the dot in its ground state or drive it into an excited state, respectively. We are able to discriminate between these two contributions and show that inelastic events can occur only if the applied bias exceeds the lowest excitation energy. Implications to energy-level spectroscopy are discussed. 相似文献