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Luciano Telesca Michele Lovallo Abuo El-Ela Amin Mohamed Mohamed ElGabry Sherif El-hady Kamal M. Abou Elenean Rafaat ElShafey Fat ElBary 《Physica A》2012
The interevent-time (IET) and interevent-distance (IED) series of seismic events occurred at Aswan area (Egypt) from 2004 to 2010 were investigated by means of the Fisher Information Measure and the Shannon entropy. The analysis was performed varying the depth and the magnitude thresholds. The results point out to an increase of level of organization and order with the decrease of magnitude threshold and the increase of depth threshold for the IET series, while the IED series are characterized by a level of uncertainty approximately constant with the threshold magnitude. The complexity measure, calculated as the product of the Fisher Information Measure and the Shannon entropy power, presents very similar pattern for both the types of seismic series, indicating an increasing complexity with the decrease of the threshold magnitude and the increase of the threshold depth. 相似文献
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The chalcone as (E)-1-([1,1′-biphenyl]-4-yl)-3-(3,4-dimethoxyphenyl)prop-2-en-1-one ( 3 ) was reacted with various active methylene compounds via Michael addition reaction under different conditions. In one hand, chalcone 3 reacted with isatin and glycine in one pot reaction via 1,3-dipolar cycloaddition reaction. On the other hand, chalcone 3 was also reacted with different N-nucleophiles via direct addition on the carbonyl group to award cyclic and/or acyclic products. Meanwhile, the reaction of chalcone 3 with S-benzylthiuronium chloride afforded the thio-Michael addition product. Chalcone 3 and 10 novel synthesized compounds were screened against two cell lines (HepG2 and MCF-7). Among of them, thiosemicarbazone 16 , oxime 14 and pyrimidine-2(1H)-thione 19 derivatives revealed an excellent activity against both cell lines (IC50 values = 6.79-12.91 μM), whereas thiosemicarbazone 16 (6.79 ± 0.5 and 7.58 ± 0.6 μM) showed the highest activity. 相似文献
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Siberian Mathematical Journal - 相似文献
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We have investigated the dynamics of phonon assisted electronic energy transfer between Eu3+ ions, experiencing different crystal fields in an amorphous Ca(PO3)2 matrix, using the technique of time-resolved fluorescence line-narrowing (TRFLN). From the concentration and temporal dependence of the transfer rate, the mechanism of the ion—ion electronic coupling has been identified as electric dipole—dipole. Both the excitation wavelength independence and the power law temperature dependence of the transfer rate identify the mechanism of the phonon participation in the transfer process as one involving a two-phonon process, with one-phonon action at each of two coupled ion sites. 相似文献
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M. A. El-sayed 《Journal of Chemical Sciences》1991,103(3):277-282
The determination of the mechanisms of chemical and physical changes is one of the principal occupations of many chemists
today. To accomplish this, the dependence of the change being examined on a number of intensive variables such as temperature,
pressure, concentration of reactants as well as the pH is usually studied. In this account, we summarize our recent studies
on the reactivity and dynamics of niobium gaseous clusters in which their changes with size are used as a new degree of freedom
that assists in deducing the mechanism of the change studied. 相似文献
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The effect of lead on the structure, electrical resistivity, internal friction, elastic modulus and thermal properties of Sn81Zn9Cd10 ternary alloys have been investigated using different experimental techniques with their analysis. In addition, properties of this alloy were compared with other Sn–Zn or Sn–Zn–Cd alloys and commercial solder alloys. It has a higher electrical resistivity, internal friction and lower elastic modulus when compared with Sn–Zn or Sn–Zn alloys with other additions such as Cd, Bi or In. The Sn61Zn9Cd10Pb20 alloy has a lower melting point, electrical resistivity and internal friction when compared with the commercial Pb–Sn solder alloy, but it has a similar elastic modulus. 相似文献
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Janusz Brzdęk El-sayed El-hady Zbigniew Leśniak 《Journal of Fixed Point Theory and Applications》2018,20(4):143
We prove a fixed point result for nonlinear operators, acting on some classes of functions with values in a dq-metric space, and show some applications of it. The result has been motivated by some issues arising in Ulam stability. We use a restricted form of a contraction condition. 相似文献