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991.
992.
Selective Exo‐Enzymatic Labeling of N‐Glycans on the Surface of Living Cells by Recombinant ST6Gal I
993.
994.
E. A. Annenkova W. Kreider O. A. Sapozhnikov 《Bulletin of the Russian Academy of Sciences: Physics》2017,81(1):76-79
A theoretical study of the growth of a spherical vapor bubble in a spherically symmetric superheated region is described. The modeling of bubble dynamics is based on considering the hydrodynamic and thermal processes inside a bubble and the surrounding liquid. 相似文献
995.
W. Helbig 《Isotopes in environmental and health studies》2013,49(3):108-109
Procedures are given for the title compounds, which allow their preparation in high chemical purity and without any depletion of the 15N-content. A nitrogen isotope exchange between NOBF4 and 15N2O3 was found, but it is too slow for preparative purposes. 相似文献
996.
The absorption spectra of a number of saturated hydrocarbons in the vacuum ultra-violet region have been examined and compared with their photoelectron and electron-loss spectra. Important conclusions about the quantum defect associated with the excited electrons and the nature of the excited states have been drawn from the relative positions of these spectra. The Rydberg bands of ethane, which were initially thought to originate in the C-C bond, have been shown to be associated with an electron largely localized in the CH3 group. 相似文献
997.
The reaction of nitrogen dioxide with carbonyl compounds having a methylene or vinyl group adjacent to the corbonyl leads to the formation of stable iminoxy radicals1-3. Evidence1,2,4 has been presented that the precursor of these iminoxy radicals is probably the corresponding oxime formed by rearrangements of the intermediate nitroso compounds. There have also been reports on the e.s.r. detection of some cis-trans isomers of some iminoxy radicals in methanol or in neat liquid1,5. We wish to report here a drastic solvent effect on the conformations of some iminoxy radicals formed by the reaction of NO2 with trifluoroacetylacetone. 相似文献
998.
J. W. Shaner 《高压研究》2013,33(1-6):469-471
Abstract The recent discovery of a solid-solid phase change in shock-compressed Mo and the theoretical interpretation suggest valence d-electron density as a major influence on structural stability. The relationship of this experimental result to the transition metal structures and alloy phase diagrams will be discussed. Specific predictions will be presented for the locations and slopes of transition metal and transition metal alloy phase boundaries. 相似文献
999.
1000.
Computer-generated binary holograms are written on a polished copper surface using single 800-nm, 120-fs pulses from a 1-kHz-repetition-rate laser system. The hologram efficiency (i.e. the power in the holographic reconstructed image relative to the incoming laser power) is investigated for different laser-structuring parameters. Theoretical diffraction grating efficiencies for a binary amplitude grating show good agreement with the experimental measurements for diameters of the laser-formed holes below the pitch. Modelling based on straightforward geometrical arguments is used to find the optimal hole size. For a coverage (i.e. relative laser-structured area) of ~43 %, the efficiency reaches ~10 %, which corresponds to a relative power transferred to one reconstructed image of ~20 %. The efficiency as a function of pitch (for fixed coverage) is fairly constant from 2 to 6 μm. 相似文献