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81.
Michael Winkler 《Journal of Differential Equations》2003,192(2):445-474
We study nonglobal positive solutions to the Dirichlet problem for ut=up(Δu+u) in bounded domains, where 0<p<2. It is proved that the set of points at which u blows up has positive measure and the blow-up rate is exactly . If either the space dimension is one or p<1, the ω-limit set of consists of continuous functions solving . In one space dimension it is shown that actually as t→T, where w coincides with an element of a one-parameter family of functions inside each component of its positivity set; furthermore, we study the size of the components of {w>0} with the result that this size is uniquely determined by Ω in the case p<1, while for p>1, the positivity set can have the maximum possible size for certain initial data, but it may also be arbitrarily close to the minimal length π. 相似文献
82.
In YBa2Cu3O7 − x
films grown on sapphire bicrystal substrates, the Josephson junctions are prepared based on artificial grain boundaries formed
by the turn of the crystal lattices about the [100] axis. The films are deposited by the laser ablation method on the buffer
CeO2 layer. The critical film temperature reaches 88.5 K with a transition width of 1.5 K. Junctions from 2 to 3-μ m wide are
integrated into the planar log-periodic antennas and their characteristics are measured at 77 K. The characteristic voltage
I
c
R
n
reaches 570 μV. With exposure to external radiation at a frequency of 113 GHz, the Shapiro steps were observed on the current-voltage
characteristic. The temperature sensitivity of this detector placed in a quasi-optical receiving unit is measured. At the
modulation of the input radiation temperature 77 K/300 K, a response of more than 200 nV is observed at the detector output.
At the modulation frequency, intrinsic noise is about 1 nV/Hz1/2, which corresponds to a temperature resolution of 1 K.
Original Russian Text ? M. Tarasov, E. Stepantsov, A. Kalabukhov, M. Kupriyanov, D. Winkler, 2007, published in Pis’ma v Zhurnal
éksperimental’noĭ i Teoreticheskoĭ Fiziki, 2007, Vol. 86, No. 11, pp. 828–831. 相似文献
83.
O. Renault N. Barrett L.F. Zagonel J.C. Cezar K. Winkler D. Funnemann 《Surface science》2007,601(20):4727-4732
The importance of energy filtering in PEEM-based imaging methods has been shown in recent years with the availability of powerful instruments. A new instrument, the NanoESCA, combines a fully electrostatic PEEM column and an aberration corrected double hemispherical analyser as energy filter. This paper reports on recently demonstrated XPEEM results using the first commercially available NanoESCA instrument operated with both synchrotron soft X-rays and monochromatic laboratory Al Kα radiation. The implementation of elemental and bonding-state specific imaging is shown with both excitation sources. The presently achieved (but not yet ultimate) lateral resolutions on energy filtered core-level images are 150 nm with a large synchrotron spot and below 1 μm with a focused laboratory source. To date this is the unique example of laboratory XPEEM core-level imaging. 相似文献
84.
Anna K. Migglautsch Melissa Willim Bettina Schweda Anton Glieder Rolf Breinbauer Margit Winkler 《Tetrahedron》2018,74(43):6199-6204
Microbial cytochrome P450 enzymes (CYPs) are able to mimic the metabolism of human CYPs. One challenge is to identify the respective drug metabolites and to compare substrate specificities to those of the human enzymes. In this study, a class VIII self-sufficient CYP from Aspergillus fumigatus (CYP505X) and variants of this enzyme were heterologously expressed in E. coli. The substrate scope of the variants was determined using active pharmaceutical ingredients (APIs) and (hetero)cyclic compounds. Capsaicin – the active compound in chili peppers – was oxidized most efficiently (4.36?μM/min) in a whole cell mediated biotransformation. The products were isolated, purified and their structures elucidated by 1D and 2D NMR. The two major metabolites showed modifications on the lipophilic side chain. Specifically, capsaicin was hydroxylated at position 8 to give (E)-8-hydroxy-N-(4-hydroxy-3-methoxybenzyl)-8-methylnon-6-enamide and epoxidized at the double bond to give N-(4-hydroxy-3-methoxybenzyl)-5-(3-isopropyloxiran-2-yl)-pentanamide. 相似文献
85.
86.
Hyperfine Interactions - Nuclear forward scattering (NFS) of synchrotron radiation was applied to investigate the electronic and magnetic properties of (i) the diamagnetic... 相似文献
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