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81.
Vitali Chkliar 《Integral Equations and Operator Theory》1997,29(3):364-367
Letu inH
2 be zero at one of the fixed points of a hyperbolic Möbius transform of the unit diskD. We will show, under some additional conditions onu, that the doubly cyclic subspaceS
u
=V
n=–
C
n
u contains nonconstant eigenfunctions of the composition operatorC
. This implies that the cyclic subspace generated byu is not minimal. If there is an infinite dimensional minimal invariant subspace ofC
(which is equivalent to the existance of an operator with only trivial invariant subspaces), then it is generated by a function with singularities at the fixed points of . 相似文献
82.
Wahl P Diekhöner L Schneider MA Vitali L Wittich G Kern K 《Physical review letters》2004,93(17):176603
Based on the experimental observation that only the close vicinity of a magnetic impurity at metal surfaces determines its Kondo behavior, we introduce a simple model which explains the Kondo temperatures observed for cobalt adatoms at the (111) and (100) surfaces of Cu, Ag, and Au. Excellent agreement between the model and scanning tunneling spectroscopy experiments is demonstrated. The Kondo temperature is shown to depend on the occupation of the d level determined by the hybridization between the adatom and the substrate with a minimum around single occupancy. 相似文献
83.
We prove the existence of solutions for some semilinear elliptic equations in the appropriate H4 spaces using the fixed‐point technique where the elliptic equation contains fourth‐order differential operators with and without Fredholm property, generalizing the previous results. 相似文献
84.
85.
Diogo Alexandre Siebert Flávia de Mello Michele Debiasi Alberton Luciano Vitali 《Natural product research》2020,34(18):2683-2688
AbstractAlzheimer’s disease and diabetes mellitus are contemporary diseases of great concern. Phenolic compounds are linked to several health benefits and could lead to novel strategies to combat these ailments. The objective of this study was to evaluate by electrophoretically-mediated microanalysis the potential inhibitory activity of the fruit juices from Plinia cauliflora (“jaboticaba”) and Eugenia uniflora (“pitanga”) toward acetylcholinesterase (AChE) and α-glucosidase, target enzymes in strategies for the treatment of these diseases. The phenolic profiles of the samples were also investigated. Jaboticaba and pitanga juices inhibited 85.90?±?1.73 and 52.67?±?1.24% of AChE activity at 5?mg mL?1, and 57.91?±?2.60 and 69.47?±?2.89% of α-glucosidase activity at 1?mg mL?1, respectively. Total phenolic content of the juices were 303.54?±?28.28 and 367.00?±?11.42 mgGA L?1, respectively. The observed inhibitory activity can be explained, at least in part, by the presence of the phenolic compounds. 相似文献
86.
We study the Banach spacesX with the following property: there is a numberδ in ]0,1[ such that for some constantC, any finite dimensional subspaceE ⊂X contains a subspaceF ⊂E with dimF≧δ dimE which isC-isomorphic to a Euclidean space. We show that if this holds for someδ in ]0,1[ then it also holds for allδ in ]0,1[ and we estimate the functionC=C(δ). We show that this property holds iff the “volume ratio” of the finite dimensional subspaces ofX are uniformly bounded. We also show that (althoughX can have this property without being of cotype 2)L
2(X) possesses this property iffX if of cotype 2. In the last part of the paper, we study theK-convex spaces which have a dual with the above property and we relate it to a certain extension property. 相似文献
87.
A simple interaction model is employed to show that radiation pressure effects, i.e., ponderomotive effects, can be profitably used to entangle radiation fields, as well as macroscopic oscillators such as movable mirrors. 相似文献
88.
Vitali Sinitsyn Koichi Hamamoto Yoshinobo Fujishiro Sergei Bredikhin Masanobu Awano 《Ionics》2006,12(3):211-213
A new multilayered electrochemical cell for NOx decomposition was prepared. The cell demonstrated good characteristics at moderate temperatures (350–450 °C) and possessed much higher selectivity with respect to NOx decomposition than previous one. It was found that the “crossover” process from high selective regime to the normal regime depends on the chemical composition of the catalytic electrode. 相似文献
89.
Victor M. Ishchenko Boris M. Bulychev Grigori L. soloveichik Vitali K. Belsky Olga G. Ellert 《Polyhedron》1984,3(7):771-774
The reduction of copper (II) chloride by molybdenum and rhenium biscyclopentadienyl hydrides upon their interaction in donor-type solvents has been studied by NMR, X-ray diffraction, and magnetic methods. It is established that the ionic complex [(η5-C5H5)2Re]+[CuCl2]? forms ortho rhombic crystals with a - 13.696(2) Å, b = 7.317(1) Å, c = 5.969(1) Å, space group Pm21n, Z = 2. The cyclopentadienyl rings make a bent-sandwich with an angle between the ring centres and Re atom of 150.1°; the ClCuCl angle being 174.8° and the ReCu minimum distance 4.346(29) Å. The solution of [(η5-C5H5)2Re]+ [CuCl2]? seems to activate the CH bond of the C5H5 rings, which results in the addition of the [(C5H5)(C5H4)ReH]+ hydride ion. 相似文献
90.
P. Danesh M. Kalitzova B. Pantchev S. Simov C. De Blasi G. Vitali M. Rossi 《Applied Physics A: Materials Science & Processing》1988,47(3):301-307
TEM, THEED and field-assisted silver ion exchange have been employed to study the glow discharge (GD) SiHCl films deposited from SiH4-SiCl4 gas mixtures. The character of the THEED patterns shows that the films are rather amorphous, and that their structure does not alter with the change in the gas mixture. The honeycomb-like morphology of the films is strongly affected by the type of gas in which SiH4 is diluted (Ar or H2). An increase in the SiCl4 partial pressure leads to the uniformity and to the decrease of the island dimension only for the films deposited from SiH4(H2)-SiCl4. A possible correlation between the film morphology and the micropore density is proposed. 相似文献