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排序方式: 共有365条查询结果,搜索用时 265 毫秒
21.
22.
Iuliu O. Marian Nicolae Bonciocat Cecilia Cristea Robert Săndulescu Monica Bucşa Mircea Vlassa 《Electroanalysis》2010,22(5):542-548
The electrochemical and spectroelectrochemical behavior of 9‐substituted with ? CN and ? COOH acridine N‐oxides with potential antitumor activity was investigated. In SER spectra of the investigated compounds, the ring stretching vibration at 1568 cm?1 for 9‐CN‐substituted compound respectively 1639 cm?1 for 9‐COOH‐substituted compound was analyzed. Cyclic voltammograms indicates that the reduction potential ?0.766 V for ? CN substituted compound increase towards ?0.745 V for ? COOH substituted compound. The proposed theoretical method in the electrochemical impedance spectroscopy uses a reference redox dielectrode and a multielectrode containing the compound. To account for the change of electrochemical impedance we have considered two theoretical quantities: a pseudocapacitance and a pseudo inductance. Two possible arrangements of them: in series, respective in parallel can be used like criteria of drug classification. 相似文献
23.
This paper considers three dichotomy concepts (exponential dichotomy, uniform exponential dichotomy and strong exponential dichotomy) in the general context of non-invertible evolution operators in Banach spaces. Connections between these concepts are illustrated. Using the notion of Green function, we give necessary conditions and sufficient ones for strong exponential dichotomy. Some illustrative examples are presented to prove that the converse of some implication type theorems are not valid. 相似文献
24.
Nicolae Adrian Secelean 《Mediterranean Journal of Mathematics》2014,11(2):361-372
Generalized countable iterated function systems (GCIFS) are an extension of countable iterated function systems by considering contractions from X × X into X instead of contractions on the compact metric space X into itself. For a GCIFS endowed with a system of probabilities we associate an invariant and normalized Borel measure whose support is just the attractor of the respective GCIFS, extending the classical Hutchinson’s construction. 相似文献
25.
In this paper we study integration with respect to a bimeasure with finite semivariation. The bimeasures as well as the functions
to be integrated, take on their values in Banach spaces.
Entrata in Redazione il 25 settembre 1998 e, in versione riveduta, il 25 giugno 1999. 相似文献
26.
Florin Nicolae 《Journal of Number Theory》2007,124(1):26-30
Let K/Q be a finite Galois extension with the Galois group G, let χ1,…,χr be the irreducible non-trivial characters of G, and let A be the C-algebra generated by the Artin L-functions L(s,χ1),…,L(s,χr). Let B be the subalgebra of A generated by the L-functions corresponding to induced characters of non-trivial one-dimensional characters of subgroups of G. We prove: (1) B is of Krull dimension r and has the same quotient field as A; (2) B=A iff G is M-group; (3) the integral closure of B in A equals A iff G is quasi-M-group. 相似文献
27.
Nicolae Manolache 《Mathematische Nachrichten》1994,167(1):157-202
28.
Nicolae Anghel 《manuscripta mathematica》1994,85(1):25-31
In this note we present a simple derivation of the Chern character of a certain finitely summable Fredholm module, associated
to the algebra of pseudodifferential operators of order ≤0 on the unit circle S1.
Research supported in part by the Texas Advanced Research Program under Grant No. 003594-071 相似文献
29.
30.
Adriana Popa Smaranda Iliescu Nicolae Doca Titus Vlase Gabriela Vlase 《International Journal of Polymer Analysis and Characterization》2017,22(1):43-50
A commercial styrene–divinylbenzene copolymer was functionalized by multistep reactions with alpha-isopropylaminophosphonic acid groups. Three different functionalized copolymers were obtained in which the phosphonic groups are in meta (1E), para (2E), and ortho (3E) positions. The thermal behavior was studied using the TG/IR hyphenated technique and kinetic analysis of thermo-oxidation under nonisothermal conditions. The evolved gas analysis confirms the partial thermo-oxidative degradation of polymeric materials, with significant preservation of the aromatic ring. The kinetic analysis was performed by three methods: Friedman, Flynn–Wall–Ozawa, and nonparametric kinetic. 相似文献