The synthesis of Cu(II) complexes derived from Schiff base ligands obtained by the condensation of 2-hydroxybenzaldehyde or terephtalic aldehyde with 4-amino-antipyrine (4-amino-2,3-dimethyl-1-phenyl-3-pyrazolin-5-one) is presented. The newly prepared compounds were characterized by( 1)H-NMR, UV-VIS, IR and ESR spectroscopy. The determination of the antimicrobial activity of the ligands and of the complexes was carried out on samples of Escherichia coli, Klebsiella pneumoniae, Acinetobacter boumanii, Pseudomonas aeruginosa, Staphylococcus aureus and Candida sp. The qualitative and quantitative antimicrobial activity test results proved that all the prepared complexes are very active, especially against samples of Ps. aeruginosa, A. Boumanii, E. coli and S. aureus. 相似文献
We define a multifractal random walk (MRW) as an anticipating pathwise integral, as limit of Riemann sums. The MRW is usually defined as the limit as \(r\rightarrow 0\) of the family of stochastic processes \((X_{r})_{r>0}\) where
where W is a Wiener process and Q an infinitely divisible cascading noise (IDC noise) not adapted to the filtration generated by W. In order to define the stochastic integral \(X_{r}(t)\) and to simulate it, one usually assumes that Q and W are independent. Our purpose is to define the MRW with a dependence structure between the IDC noise Q and the Wiener process W. Our construction is done by using Riemann sums, and it allows the simulation of the process.
We analyze the transient nonclassical behaviour of a single-mode field whose interaction with an environment is governed by
the quantum optical master equation. Our analytic method makes use of the generalized characteristic function of the field
state. First, we find a time at which all squeezing effects disappear by decoherence regardless of the initial state of the
mode. In the case of an input even coherent state, an unusual modification of higher-order squeezing at low values of thermal
mean occupancy transferred to the field is found and discussed. For the same initial state, we also perform a comprehensive
analysis of the mixing process during the interaction with the reservoir. We prove that a maximum in the evolution of the
2-entropy of the attenuated mode exists on condition that its initial mean photon number exceeds the mean occupancy of the
reservoir. This transient mixing enhancement can be considered as a quantum effect of the initial state on the mode damping.
Received 22 April 1999 and Received in final form 2 November 1999 相似文献
The homogeneous-inhomogeneous transitions of a two-dimensional electron gas in a strong perpendicular magnetic field are studied in the particular case when half of the states in a spin splitted Landau level are occupied. To this end the dielectric susceptibility in the homogeneous states as well as the free energy in the modulated states are calculated. Unless theg factor dos not exceed a certain value the charge-density waves are stable in an interval of finite temperatures. 相似文献
In this label-free surface-enhanced Raman scattering (SERS) study of genomic DNA, we demonstrate that the cancer-specific DNA methylation pattern translates into specific spectral differences. Thus, DNA extracted from an acute myeloid leukemia (AML) cell line presented a decreased intensity of the 1005 cm−1 band of 5-methylcytosine compared to normal DNA, in line with the well-described hypomethylation of cancer DNA. The unique methylation pattern of cancer DNA also influences the DNA adsorption geometry, resulting in higher adenine SERS intensities for cancer DNA. The possibility of detecting cancer DNA based on its SERS spectrum was validated on peripheral blood genomic DNA samples from n = 17 AML patients and n = 17 control samples, yielding an overall classification of 82% based on the 1005 cm−1 band of 5-methylcytosine. By demonstrating the potential of SERS in assessing the methylation status in the case of real-life DNA samples, the study paves the way for novel methods of diagnosing cancer.