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611.
Patrizia Diana Antonina StagnoPaola Barraja Alessandra MontalbanoAnna Carbone Barbara ParrinoGirolamo Cirrincione 《Tetrahedron》2011,67(19):3374-3379
Derivatives of the new ring system pyrrolizino[2,3-b]indol-4(5H)-one were prepared in four steps starting from substituted benzonitriles bearing a functionalized amino group in the adjacent position. The unsubstituted- and the dimethoxy-pyrrolizinoindolones 5a and 5b exhibited modest activity against the HL-60(TB) human leukemia cell line, whereas the N-methylated dimethoxy-pyrrolizinoindolone 6b showed to be selective against MOLT-4 leukemia, A549/ATCC, HOP-92, and NCI-H460 non-small cell lung cancer, and CAKI-1 renal cancer cell lines. 相似文献
612.
Patrizia Diana Annamaria MartoranaPaola Barraja Alessandra MontalbanoAnna Carbone Girolamo Cirrincione 《Tetrahedron》2011,67(11):2072-2080
A novel synthetic approach to the synthesis of 3-substituted isoindoles through nucleophilic substitution of 3-halo derivatives by charged carbon, and neutral nitrogen, oxygen, and sulfur nucleophiles, assisted by a 1-acyl group, is reported. Aryl-thio-isoindoles, obtained through a direct nucleophilic substitution with sulfur nucleophiles, showed cytotoxic activity, with GI50 values from micromolar to sub-micromolar concentrations, against the total number of cell lines investigated. 相似文献
613.
The complex spatio-temporal dynamics generated by electrohydrodynamics instabilities in a nematic liquid crystal under the
action of a driving oscillating electric field is investigated. Quasi-stationary convective structures which are visible at
large scales are broken into chaotic patterns at higher driving voltages, thus generating small-scale structures. Scaling
analysis reveals that these small-scale structures self-organize in a network of subleading structures which are reminescent
of convective rolls. This network persists well inside the chaotic regimes, disappearing only at very high voltages, where
stochastic dynamical scattering mode takes place. 相似文献
614.
Štefan Chromik Marianna Španková Jozef Liday Peter Lobotka 《Applied Surface Science》2008,254(12):3635-3637
Epitaxial MgO thin films have been grown on semiinsulating GaAs (0 0 1) substrates using electron beam (e-beam) evaporation. X-ray diffraction indicates c-axis oriented MgO with (0 0 2) reflection only and rocking curve widths ∼2.2-3°. Transmission electron microscopy (TEM) analyses confirm an epitaxial growth of the MgO films. We study the microstructure and the defects at the interface between the MgO film and the GaAs substrate. Auger electron Spectroscopy (AES) concentration depth profiles reveal no contamination of the MgO films by As and Ga at different temperatures of the deposition process. 相似文献
615.
By means of time-resolved electron crystallography, we report direct observation of the structural dynamics of graphite, providing new insights into the processes involving coherent lattice motions and ultrafast graphene ablation. When graphite is excited by an ultrashort laser pulse, the excited carriers reach their equilibrium in less then one picosecond by transferring heat to a subset of strongly coupled optical phonons. The time-resolved diffraction data show that on such a time scale the crystal undergoes a contraction whose velocity depends on the excitation fluence. The contraction is followed by a large expansion which, at sufficiently high fluence, leads to the ablation of entire graphene layers, as recently predicted theoretically. 相似文献
616.
G. Morello F. Della SalaL. Carbone L. MannaR. Cingolani M. De Giorgi 《Superlattices and Microstructures》2010
In this contribution we report on an optical nonlinearity featuring colloidal seeded grown CdSe/CdS nanorods (NRs). It consists of a photoluminescence (PL) blueshift of single rod spectra with increasing laser power and a transient, power-dependent redshift of the spectra studied by time resolved PL measurement, strictly related to the multicarrier scattering occurring at high excitation density. We attribute this nonlinearity to a photo-induced screening of an internal field, originating from the piezoelectric polarization induced at the core/shell interface. 相似文献
617.
Välikangas Juho Laine Petteri Hietaniemi Marianna Hu Tao Selent Marcin Tynjälä Pekka Lassi Ulla 《Journal of Solid State Electrochemistry》2023,27(3):641-654
Journal of Solid State Electrochemistry - This article presents a process for producing LiNi1-xAlxO2 (0 < × < 0.05) cathode material with... 相似文献