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81.
In order to get results of non-embedding of flag-manifolds in the total space of sphere bundles we consider algebraic properties
of these two families of manifolds.
The main theorem (2.3) gives a general a non-embedding result in terms of algebraic invariants and this theorem is applied
to the case of the flag-manifolds. 相似文献
82.
83.
Andresa JS Reis RM Gonzalez EP Santos LS Eberlin MN de Paula Nascente PA Tanimoto ST Machado SA Rodrigues-Filho UP 《Journal of colloid and interface science》2005,286(1):303-309
The present paper describes the one-pot procedure for the formation of self-assembled thin films of two silanes on the model oxidized silicon wafer, SiO2/Si. SiO2/Si is a model system for other surfaces, such as glass, quartz, aerosol, and silica gel. MALDI-TOF MS with and without a matrix, XPS, and AFM have confirmed the formation of self-assembled thin films of both 3-imidazolylpropyltrimethoxysilane (3-IPTS) and 4-(N-propyltriethoxysilane-imino)pyridine (4-PTSIP) on the SiO2/Si surface after 30 min. Longer adsorption times lead to the deposition of nonreacted 3-IPTS precursors and the formation of agglomerates on the 3-IPTS monolayer. The formation of 4-PTSIP self-assembled layers on SiO2/Si is also demonstrated. The present results for the flat SiO2/Si surface can lead to a better understanding of the formation of a stationary phase for affinity chromatography as well as transition-metal-supported catalysts on silica and their relationship with surface roughness and ordering. The 3-IPTS and 4-PTSIP modified SiO2/Si wafers can also be envisaged as possible built-on-silicon thin-layer chromatography (TLC) extraction devices for metal determination or N-heterocycle analytes, such as histidine and histamine, with "on-spot" MALDI-TOF MS detection. 相似文献
84.
Fernando?CobosEmail author Luz M.?Fernández-Cabrera Antonio?Manzano Antón?Martínez 《Mathematische Zeitschrift》2005,250(2):267-277
We study the interpolation properties of Asplund operators by the complex method, as well as by general J- and K-methods.Mathematics Subject Classification (2000): 46B70, 47B10 相似文献
85.
We investigate how the insertion of an oxygen atom in an atomically thin gold nanowire can affect its rupture. We find, using ab initio total energy density functional theory calculations, that O atoms when inserted in gold nanowires form not only stable but also very strong bonds, in such a way that they can extract atoms from a stable tip, serving in this way as a clamp that could be used to pull a string of gold atoms. 相似文献
86.
The dynamics of the title five-atom atmospheric reaction is studied by the quasiclassical trajectory method for vibrational states of OH over the range 2 < or = v < or = 9 and initial vibrational energies of O3 between 9 and 21 kcal mol-1 using a previously reported double many-body expansion potential energy surface for HO4(2A). The results show that the reaction is controlled by both capture- and barrier-type mechanisms, with the rate constants depending strongly on the reactants' internal energy content. Also suggested from the magnitude of the calculated rate coefficients is that the title processes may not be ignorable when studying the stratospheric ozone budget. 相似文献
87.
A graph is terminal-pairable with respect to a demand (loopless) multigraph on the same vertex set as , if there exist edge-disjoint paths joining the end vertices of every demand edge of . In this short note, we improve the upper bound on the largest with the property that the complete graph on vertices is terminal-pairable with respect to any demand multigraph of maximum degree at most . This disproves a conjecture originally stated by Csaba, Faudree, Gyárfás, Lehel and Schelp. 相似文献
88.
Luz?M.?Fernández-CabreraEmail author Antón?Martínez 《Journal of Fourier Analysis and Applications》2018,24(5):1181-1203
We establish an analog for bilinear operators of the compactness interpolation result for bounded linear operators proved by Cwikel and Cobos, Kühn and Schonbek. We work with the assumption that \(T:(A_0+A_1) \times (B_0+B_1) \longrightarrow E_0+E_1\) is bounded, but we also study the case when this does not hold. Applications are given to compactness of convolution operators and compactness of commutators of bilinear Calderón–Zygmund operators. 相似文献
89.
Lopes SC Soares CM Baptista AM Goormaghtigh E Cabral BJ Castanho MA 《The journal of physical chemistry. B》2006,110(7):3385-3394
The analgesic dipeptide kyotorphin (L-Tyr-L-Arg) and an acylated kyotorphin derivative were studied by a combination of theoretical (molecular dynamics simulation and quantum mechanics methods) and experimental (fluorescence and infrared spectroscopies) approaches both in solution and in model systems of membranes. At biological pH the peptides have a neutral net charge. Nevertheless, their phenolic rings interact with phospholipid molecules (partition coefficient varies from 6 x 10(2) to 2 x 10(4), depending on the lipid and pH used) despite being exposed to the aqueous bulk medium. The lowest energy transition dipole moment is displaced from the normal to the lipid bilayer by 20 degrees on average. The observed extensive interaction, pK(a), precise location, and well-defined orientation in membranes combined with the ability to discriminate rigid raftlike membrane domains suggest that kyotorphin meets the structural constraints needed for receptor-ligand interaction. The acylated kyotorphin derivative mimics kyotorphin properties and represents a promising way for entrapment in a drug carrier and transport across the blood-brain barrier. 相似文献
90.