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911.
A general theory of collineation groups generated by quartic groups of even order is considered. Applications are given to collineation groups generated by ‘large’ quartic groups. © 2005 Wiley Periodicals, Inc. J Combin Designs 13: 195–210, 2005. 相似文献
912.
Mauro Marini 《Journal of Mathematical Analysis and Applications》2004,295(2):459-472
The problem of oscillation of a second order nonlinear difference system is considered and conditions for oscillation are derived by means of a complete analysis of nonoscillatory solutions. The case of systems with deviating arguments is also analyzed, and the results are shown to significantly generalize some existing ones. 相似文献
913.
Gianfranco Cariolaro Mauro Fregolent Alessandro Tonello Costantino De angelis 《Optical and Quantum Electronics》2004,36(10):853-880
Chirped Hermite–Gaussian functions shows outstanding potentialities in mathematical models for linear and non linear pulse propagation in optical fibers. We propose three generalized subclasses of Hermite–Gaussian functions as natural extension to the complex domain. We exemplify the properties of these subclasses by analyzing some relevant cases of pulse oscillatory dynamics governed by nonlinear Schrödinger equation with constant or periodic coefficfients. 相似文献
914.
915.
D. Chowdhury M. Mlejnek Y. Mauro 《Journal of Optical and Fiber Communications Reports》2004,1(2):141-149
A procedure for evaluating system performance considering all orders of polarization mode dispersion (PMD) is
presented. The method provides engineering rules for computing system penalty
introduced by PMD. Computer simulation of PMD induced penalty indicates that
for generating a realistic system budget, effect of higher order PMD in
presence of chromatic dispersion is essential. Considering all of these
penalties, in order to obtain a system-reach of 3200 km at 40 Gb/s, a fiber
PMD of less than 0.04 ps/km1/2 is required when at the signal
wavelength chromatic dispersion is 0. In presence of 18 ps/nm chromatic
dispersion for the same system reach this PMD value reduces to about 0.02
ps/km1/2. 相似文献
916.
Chen Hu Shuping Liu Mauro Fasoli Anna Vedda Martin Nikl Xiqi Feng Yubai Pan 《固体物理学:研究快报》2015,9(4):245-249
Electron traps are known to a have great influence on the carriers transport process in Ce based scintillators. On the other hand, the role of hole traps in the scintillation process has been less considered. By means of electron spin resonance (ESR), we detected hole traps in highly Ce‐doped LuAG:Ce,Mg ceramics in the form of σ‐type O– centers. The g ‐tensor components turn out to be g⊥ = 2.0103, and g|| = 2.0023, revealing the axial symmetry of these defects. Mg‐perturbed variants of O– centers are proposed to exist in LuAG:Ce,Mg. Their occurrence is related to an elongated Mg–O bond as evidenced by DFT calculations. Finally, the multiple role of O– centers in the scintillation process is discussed.
917.
Michele Karoline Lima Daniela Martins Fernandes Marcela Fernandes Silva Mauro Luciano Baesso Antonio Medina Neto Gutierrez Rodriguês de Morais Celso Vataru Nakamura Angelo de Oliveira Caleare Ana Adelina Winkler Hechenleitner Edgardo Alfonso Gómez Pineda 《Journal of Sol-Gel Science and Technology》2014,72(2):301-309
Pure and Co-doped ZnO nanoparticles were synthesized with different cobalt levels (1–10 mol%) via adapted sol–gel method using water as solvent and characterized by X-ray diffraction, transmission electron microscopy, Raman spectroscopy and photoacoustic absorption spectroscopy. The results showed that all the samples have hexagonal wurtzite structure, with no evidence of any secondary phases until 10 mol% of the dopant. The average crystallite size of the samples was in the range of 25–50 nm, do not showing significant differences with the increase of the dopant level. However, the band gap energy of the nanoparticles decreases from 2.98 eV (pure ZnO) to 1.95 eV (10 mol% of Co). The photocatalytic activity of the samples was evaluated on the removal of methylene blue under visible light irradiation, which revealed an efficiency reduction by Co-doping ZnO. The antibacterial property was carried out indicating activity of the prepared samples against gram-positive bacteria. 相似文献
918.
A novel hydrogen pressure swing adsorption system has been studied that is applied to an advanced integrated gasification combined cycle plant for cogenerating power and ultrapure hydrogen (99.99+ mol%) with CO2 capture. In designing the H2 PSA, it is essential to increase the recovery of ultrapure hydrogen product to its maximum since the power consumption for compressing the H2 PSA tail gas up to the gas turbine operating pressure should be minimised to save the total auxiliary power consumption of the advanced IGCC plant. In this study, it is sought to increase the H2 recovery by increasing the complexity of the PSA step configuration that enables a PSA cycle to have a lower feed flow to one column for adsorption and more pressure equalisation steps. As a result the H2 recovery reaches a maximum around 93 % with a Polybed H2 PSA system having twelve columns and the step configuration contains simultaneous adsorption at three columns and four-stage pressure equalisation. 相似文献
919.
Dr. Martín Regueiro‐Figueroa Dr. Gabriele A. Rolla Dr. David Esteban‐Gómez Dr. Andrés de Blas Dr. Teresa Rodríguez‐Blas Prof. Mauro Botta Dr. Carlos Platas‐Iglesias 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(52):17300-17305
Stable Mn2+ mono‐ and binuclear complexes containing pentadentate 6,6′‐((methylazanediyl)bis(methylene))dipicolinic acid coordinating units give remarkably high relaxivities due to the presence of two inner‐sphere water molecules. The mononuclear derivative binds human serum albumin (HSA) with an association constant of 3372 M ?1, which results in the replacement of the coordinated water molecules by donor atoms of protein residues. The dinuclear analogue also binds HSA while leaving one of the Mn2+ centres exposed to the solvent with two coordinated water molecules. Thus, this complex shows remarkably high relaxivities upon protein binding (39.0 mM ?1 s?1 per Mn, at 20 MHz and 37 °C). 相似文献
920.
Cristiana da Silva Dênis A. M. da Silva Fillipe V. Rocha Carolina V. Barra Regina C. G. Frem Adelino V. G. Netto Antonio E. Mauro Eduardo T. de Almeida 《Journal of Thermal Analysis and Calorimetry》2014,117(3):1327-1334
The mononuclear pyrazolyl complexes [PdCl2(HIPz)2] (1), [PdBr2(HIPz)2] (2), [PdI2(HIPz)2] (3), [Pd(SCN)2(HIPz)2] (4), and [Pd(NHCOIPz)2] (5) have been prepared. Compound 1 was obtained from the displacement of acetonitrile from [PdCl2(CH3CN)2] precursor by the 4-iodopyrazole (HIPz) ligand, whereas 2–5 were synthesized by substitution of the chlorido in 1 by the respective anionic group. The compounds were characterized by elemental analysis, infrared spectroscopy, and 1H NMR spectroscopy. The thermal behavior of 1–5 has been studied by TG and DTA. The thermal stability of [PdX2(HIPz)2] compounds varies according to the trends X = Cl? < I? ? SCN?< Br?. No stable intermediates were isolated during the thermal decompositions due to the overlap of the degradation processes. The final products of the thermal decompositions were characterized as metallic palladium by X-ray powder diffraction. 相似文献