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21.
Joseph R. Lakowicz Ignacy Gryczynski Henryk Cherek Gabor Laczko Nanda Joshi 《Trends in analytical chemistry : TRAC》1986,5(10):257-263
The fluorescence emission from complex chemical and biological samples can be resolved by measuring the frequency-response of the emission, which is now possible from 1 to 2000 MHz. The frequency-response allows determination of the components in a mixture, construction of time-resolved emission spectra, and measurement of the dynamic and hydrodynamic properties of biological macromolecules. The instrumentation is relatively simple, and data acquisition times can be short. At present, this method may be superior to direct measurements of time-resolved fluorescence emission. 相似文献
22.
Based on the all-valence ZDO SCF approximation a procedure for estimating the basis set superposition error (BSSE ) in semiempirical CNDO /INDO methods has been proposed. The results of the calculation show that the BSSE effect may improve the results obtained from the standard CNDO /INDO supermolecule calculation. The estimated BSSE effect enables one to explain some recently reported artificial structures for water and ethylene dimers. 相似文献
23.
We give a necessary and sufficient condition for the uniformly non-l
n
(1)
property of Musielak-Orlicz sequence spacesl
Φ generated by a sequence Φ=(ϕn:n⩾l) of finite Orlicz functions such that
for eachn∈ℕ. As a result, forn
0⩾2, there exist spacesl
Φ which are only uniformly non-l
n
(1)
forn⩾n
0. Moreover we obtain a characterization of uniformly non-l
n
(1)
and reflexive Orlicz sequence spaces over a wide class of purely atomic measures and of uniformly non-l
n
(1)
Nakano sequence spaces. This extends a result of Luxemburg in [19].
Submitted in memory of Professor W. Orlicz 相似文献
24.
Stańczak P Valensin D Juszczyk P Grzonka Z Valensin G Bernardi F Molteni E Gaggelli E Kozłowski H 《Chemical communications (Cambridge, England)》2005,(26):3298-3300
The interaction between the single hexarepeat unit of chicken prion protein [ChPrP(54-59)] and Cu(II) was investigated by NMR, finding different coordination modes for the trans/trans and cis/trans isomers. 相似文献
25.
Valensin D Luczkowski M Mancini FM Legowska A Gaggelli E Valensin G Rolka K Kozlowski H 《Dalton transactions (Cambridge, England : 2003)》2004,(9):1284-1293
Potentiometric and spectroscopic data have shown that octarepeat dimer and tetramer are much more effective ligands for Cu(II) ions than simple octapeptide. Thus, the whole N-terminal segment of prion protein due to cooperative effects, could be more effective in binding of Cu(II) than simple peptides containing a His residue. The gain of the Cu(II) binding by longer octarepeat peptides derives from the involvement of up to four imidazoles in the coordination of the first Cu(II) ion. This type of binding increases the order of the peptide structure, which allows successive metal ions for easier coordination. 相似文献
26.
We present the Rothe method for the McKendrick-von Foerster equation with initial and boundary conditions. This method is well known as an abstract Euler scheme in extensive literature, e.g. K. Rektorys, The Method of Discretization in Time and Partial Differential Equations, Reidel, Dordrecht, 1982. Various Banach spaces are exploited, the most popular being the space of bounded and continuous functions. We prove the boundedness of approximate solutions and stability of the Rothe method in L ∞ and L 1 norms. Proofs of these results are based on comparison inequalities. Our theory is illustrated by numerical experiments. Our research is motivated by certain models of mathematical biology. 相似文献
27.
28.
29.
Barbara Milczarska Henryk Foks Urszula Dobrzycka Zofia Zwolska Ewa Augustynowicz-Kopeć 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2793-2799
The 4-hydroxyalkyl-1,2,4-triazole-3-thiones cyclization allowed us to work out the effective method of 1,3-thiazacycloalkyl[3,2-b]-1,2,4-triazoles synthesis. Some of the compounds that were obtained were tested for their tuberculostatic activity. 相似文献
30.
Barbara Milczarska Henryk Foks Zofia Zwolska 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):1977-1992
The 2-cyano-6-chloropyrazine's chlorine atom reactivity was substituted with amines 1,4-dioxo-8-azaspiro-[4, 5]-decane and 1-ethoxycarbonylpiperazine. The substrates thus obtained were used in the syntheses of the new derivatives, which were tested for their tuberculostatic activity. Minimum inhibitory concentration (MIC) value of the most active ones ( 5b , 12a , 14b , 16b , 21b ) was 25 μ g/mL. 相似文献