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101.
M. C. Kouassi J. Dalmasso H. Maria G. Ardisson M. Hussonnois 《Journal of Radioanalytical and Nuclear Chemistry》1990,144(5):387-396
The decay of a225Ac source in equilibrium mixture with its decay products was investigated using high-resolution HP/Ge/ detectors. Energies and intensities of more than 78 -photons were measured with an improved accuracy; 44 of them are reported for the first time. A tentative221Fr level scheme was built on the basis of good energy sum relationships; seven new221Fr excited levels are proposed at 496.9, 570.9, 603.5, 630.7, 637.7, 649.0 and 758.9 keV. 相似文献
102.
M. Serge Dubuc 《Probability Theory and Related Fields》1971,19(4):281-290
Sans résumé 相似文献
103.
An induction period has been observed in the pyrolysis of ethane in a continuous-flow stirred tank reactor at 530°C. The rate constants of the initiation, determining propagation and termination steps, have been determined. 相似文献
104.
Serge Vasilach 《Rendiconti del Circolo Matematico di Palermo》1979,28(3):377-386
In our preceding paper [2], we have studied the fundamental properties of the heterogeneous algebras, and constructed the projective limits in the category of these algebras and in the category of abstract automata. The present article is devoted to the study ofdirect limits in the same categories. 相似文献
105.
Serge Steinblatt 《Optics Communications》1983,47(6):391-394
An experimental method to measure the optical anisotropy profiles of optical fibers and preforms is presented. The local values of nz?nr and nz?n?, (r,?,z) being a cylindrical coordinate system associated with the fiber or preform, are obtained. 相似文献
106.
107.
108.
Le Grand F George G Akoka S 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2005,174(1):171-176
Deuterium site-specific natural isotope abundance (Ai) is routinely measured by NMR spectroscopy and quantified using an internal reference peak. This study demonstrates that the substitution of the chemical compound used as internal reference by an electronically generated signal (the ERETIC method) allows a dramatic reduction of the experimental time. Measurements of Ai on eight samples of methylsalicylate have been performed using either an internal reference (TMU) or ERETIC. No significant difference in accuracy or precision had been found between the two methods. However, because the method is applicable in partially saturated conditions, the experiment time was divided by a factor of 4 and the drawbacks associated with an internal chemical reference were avoided when ERETIC was used. 相似文献
109.
Current optical interferometers are affected by unknown turbulent phases on each telescope. We account for this lack of phase information by introducing system aberration parameters, and we solve the image reconstruction problem by minimizing an original joint criterion in the aberrations and in the object. We validate this method by means of simulations. Tests on experimental data are under way. 相似文献
110.
CO photodesorption from Pt(111) induced by femtosecond laser pulses is probed by IR+visible sum frequency generation (SFG). Steady state analysis of SFG spectra at varying CO pressure and laser fluence allows one to measure a approximately 5 orders of magnitude decrease of the photodesorption rate constant when CO coverage decreases from 0.37 to 0.07 monolayer. We ascribe this effect in the framework of the Menzel-Gomer-Redhead mechanism to electron delocalization in the CO layer. The lifetime of electronic excitation decreases when coverage decreases. 相似文献