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31.
For a connected finite graph G and a subset V0 of its vertex set, a distance-residual subgraph is a subgraph induced on the set of vertices at the maximal distance from V0. Some properties and examples of distance-residual subgraphs of vertex-transitive, edge-transitive, bipartite and semisymmetric graphs are presented. The relations between the distance-residual subgraphs of product graphs and their factors are explored. 相似文献
32.
Daniela Silva Maranho Renata Galvão de Lima Fernando Lucas Primo Roberto Santana da Silva Antonio Claudio Tedesco 《Photochemistry and photobiology》2009,85(3):705-713
Under continuous photolysis at 675 nm, liposomal zinc phthalocyanine associated with nitrosyl ruthenium complex [Ru(NH.NHq)(tpy)NO]3+ showed the detection and quantification of nitric oxide (NO) and singlet oxygen (1 O2 ) release. Photophysical and photochemical results demonstrated that the interaction between the nitrosyl ruthenium complex and the photosensitizer can enable an electron transfer process from the photosensitizer to the nitrosyl ruthenium complex which leads to NO release. Synergistic action of both photosensitizers and the nitrosyl ruthenium complex results in the production of reactive oxygen species and reactive nitrogen species, which is a potent oxidizing agent to many biological tissues, in particular neoplastic cells. 相似文献
33.
Fernando L. Primo Marcilene M.A. Rodrigues Andreza R. Simioni Maria V.L.B. Bentley Paulo C. Morais Antonio C. Tedesco 《Journal of magnetism and magnetic materials》2008,320(14):e211-e214
In this study was developed a new nano drug delivery system (NDDS) based on association of biodegradable surfactants with biocompatible magnetic fluid of maguemita citrate derivative. This formulation consists in a magnetic emulsion with nanostructured colloidal particles. Preliminary in vitro experiments showed that the formulation presents a great potential for synergic application in the topical release of photosensitizer drug (PS) and excellent target tissue properties in the photodynamic therapy (PDT) combined with hyperthermia (HPT) protocols. The physical chemistry characterization and in vitro assays were carried out by Zn(II) Phtalocyanine (ZnPc) photosensitizer incorporated into NDDS in the absence and the presence of magnetic fluid, showed good results and high biocompatibility. In vitro experiments were accomplished by tape-stripping protocols for quantification of drug association with different skin tissue layers. This technique is a classical method for analyses of drug release in stratum corneum and epidermis+dermis skin layers. The NDDS formulations were applied directly in pig skin (tissue model) fixed in the cell's Franz device with receptor medium container with a PBS/EtOH 20% solution (10 mM, pH 7.4) at 37 °C. After 12 h of topical administration stratum corneum was removed from fifty tapes and the ZnPc retained was evaluated by solvent extraction in dimetil-sulphoxide under ultrasonic bath. These results indicated that magnetic nanoemulsion (MNE) increase the drug release on the deeper skin layers when compared with classical formulation in the absence of magnetic particles. This could be related with the increase of biocompatibility of NDDS due to the great affinity for the polar extracelullar matrix in the skin and also for the increase in the drug partition inside of corneocites wall. 相似文献
34.
De Sousa RP Barbosa LF De Oliveira AF Mathias L Braz-Filho R Vieira IJ 《Natural product research》2005,19(2):151-155
Cymosanine (1) and three further known quassinoids, cedronin (2), chaparrinone (3), and simarolide (4), were isolated from the root bark of Simaba subcymosa. The structures were established by spectroscopic data, mainly 1D, 2D NMR and mass spectra. 相似文献
35.
Primo? Rebernik Ribi? 《Surface science》2007,601(5):L25
Morphology of high-vacuum deposited rubrene thin films on the annealed (0 0 0 1) vicinal sapphire surfaces was studied by atomic force microscopy in non-contact mode. Atomic force microscopy images of rubrene thin films indicate that a regular array of steps on the sapphire surface acts as a template for the growth of the arrays of rubrene nanosize wires. To further demonstrate that morphological features of a substrate are crucial in determining the morphology of rubrene layers we have grown rubrene on the sapphire surfaces that were characterized by the terrace-and-step morphology with islands. We have found preferential nucleation of rubrene molecules at the intersection between a terrace and a step, as well as around the islands located on terraces. 相似文献
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37.
Martin Juckel Primož Koželj Yurii Prots Alim Ormeci Ulrich Burkhardt Andreas Leithe-Jasper Eteri Svanidze 《无机化学与普通化学杂志》2020,646(14):1238-1243
Intermediate valence behavior is frequently observed in materials containing Ce, Yb, Eu, Sm, or Tm. In the current work, we report synthesis and characterization of Yb2Cu9Al8 (Th2Zn17 structure type). Its intermediate valence behavior can be described by an excitation energy Eex/kB = 319 K and a spin fluctuation temperature Tsf = 60 K. The valence state of Yb is estimated to be close to 2.04 for the low-temperature region. The valence gradually evolves to the value of 2.80 at T = 400 K. The specific heat coefficient of γexp = 59 mJ · molYb–1 · K–2 indicates a moderate effective mass enhancement, together with finite density of states at the Fermi level. The latter is also confirmed by the band structure calculations. 相似文献
38.
Primo A Marino T Corma A Molinari R García H 《Journal of the American Chemical Society》2011,133(18):6930-6933
When irradiated with visible light (λ > 400 nm) 1 wt % gold-supported ceria nanoparticles generate oxygen from water (10.5 μmol·h(-1)) more efficiently than the standard WO(3) (1.7 μmol·h(-1)) even under UV irradiation (9.5 μmol·h(-1)). This remarkable photocatalytic activity arises from a novel preparation method to reduce the particle size of ceria (5 nm) by means of electrostatic binding of Ce(4+) to alginate gel, subsequent supercritical CO(2) drying, and calcination. The low loading of Au is crucial for the observed high catalytic activity. 相似文献
39.
40.
Pérez-Andrés M Benito JJ Rodríguez-Fernández E Corradetti B Primo D Manzano JL Orfao A Criado JJ 《Dalton transactions (Cambridge, England : 2003)》2008,(44):6159-6164
The present paper describes for the first time an intrinsic fluorescent square-planar platinum(II) complex carrying two ursodeoxycholate ligands ([Pt(UDC)2(en)], where UDC(-) = ursodeoxycholate), that emits at room temperature once free in solution. Kinetic studies were carried out in aqueous solution and in the presence of different NaCl concentrations: 4 mM (similar to cytoplasmic concentration) and 150 mM (similar to plasmatic concentration). This novel compound was synthesized from a [PtCl2(en)] complex and shows increased cytotoxic activity against both resting and cycling HeLa cells, with no toxicity for cell lines derived from neoplastic haematopoietic cells. 相似文献