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1.
Synthesis,spectral investigation and development of tetrahedral copper(II) complexes as artificial metallonucleases and antimalarial agents 下载免费PDF全文
Seven new copper(II) complexes of type [Cu(A)(L)]?H2O (A = sparfloxacin, ciprofloxacin, levofloxacin, gatifloxacin, pefloxacin, ofloxacin, norfloxacin; L = 5‐[(3‐chlorophenyl)diazenyl]‐4‐hydroxy‐1,3‐thiazole‐2(3H)‐thione) were synthesized and characterized using elemental and thermogravimetric analyses, and electronic, electron paramagnetic resonance (EPR), Fourier transform infrared and liquid chromatography–mass spectroscopies. Tetrahedral geometry around copper is assigned in all complexes using EPR and electronic spectral analyses. All complexes were investigated for their interaction with herring sperm DNA utilizing absorption titration (Kb = 1.27–3.13 × 105 M?1) and hydrodynamic volume measurement studies. The studies suggest the classical intercalative mode of DNA binding. The cleavage reaction on pUC19 DNA was monitored by agarose gel electrophoresis. The results indicate that the Cu(II) complexes can more effectively promote the cleavage of plasmid DNA. The superoxide dismutase mimic activity of the complexes was evaluated by nitroblue tetrazolium assay, and the complexes catalysed the dismutation of superoxide at pH = 7.8 with IC50 values in the range 0.597–0.900 μM. The complexes were screened for their in vitro antibacterial activity against five pathogenic bacteria. All the complexes are good cytotoxic agents and show LC50 values ranging from 5.559 to 11.912 µg ml?1. All newly synthesized Cu(II) complexes were also evaluated for their in vitro antimalarial activity against Plasmodium falciparum strain (IC50 = 0.62–2.0 µg ml?1). Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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P. C. Mehta 《Hyperfine Interactions》1987,37(1-4):325-345
Optical data processing is an advancing field which has received much attention in recent years. Optical techniques have already
shown their applicability in target identification, advanced signal processing operations and advanced linear algebra operations.
The potential capabilities of processing of data using photons instead of electrons as the carrier of information have established,
beyond any doubt, that the optical techniques will be the next generation technology surpassing electronic techniques in some
important areas such as air traffic control, missile guidance and remote sensing. Although great strides have been made in
all the areas of optical data processing, the goal of high performance, high speed and very accurate all-optical computers
would be realised only around the year 1995. The main difficulty is that the required materials for high resolution and fast
spatial light modulators and optical interconnects are yet to be perfected. The present paper reviews the recent trends and
the future prospects of optical data processing. 相似文献
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The objective of this paper is to investigate the role of the set of irrational numbers as the codomain of order-preserving
functions defined on topological totally preordered sets. We will show that although the set of irrational numbers does not
satisfy the Debreu property it is still nonetheless true that any lower (respectively, upper) semicontinuous total preorder
representable by a real-valued strictly isotone function (semicontinuous or not) also admits a representation by means of
a lower (respectively, upper) semicontinuous strictly isotone function that takes values in the set of irrational numbers.
These results are obtained by means of a direct construction. Moreover, they can be related to Cantor’s characterization of the real line to obtain much more general results on the semicontinuous
Debreu properties of a wide family of subsets of the real line.
相似文献
6.
W.P. RDZANEK JR 《Journal of sound and vibration》2002,249(2):307-323
The standardized mutual active and reactive sound power of a clamped plate, representing the energy aspect of the reciprocal interactions of two different in vacuo modes, has been computed. It was assumed that the vibrations are axisymmetric, elastic and time harmonic, the plate's transverse deflection is small as compared with the plate's size, and that the vibration velocity is small as compared with the acoustic wavenumber generated. The Kirchhoff-Love theory of a perfectly elastic plate was used. The integral formulae for the mutual sound power were transformed into their Hankel representations which made possible their subsequent computation. A closed path integral was used to express the integral in its Hankel representation to compute the mutual active sound power. The asymptotic stationary phase method was used to compute the two magnitudes, i.e., the mutual active and reactive sound power. The results obtained are the asymptotic formulae valid for the acoustically fast waves. The oscillating as well as the non-oscillating terms have been identified in the formulae to make possible their further separate analysis. The availability of the asymptotic formulae makes possible some fast numerical computations of the mutual sound power. Moreover, the formulae presented herein, together with those for the individual modes known from the literature, make a complete basis for further computations of the total sound power of the plate's damped and forced vibrations in fluid. 相似文献
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Excess volumes V
E
of binary liquid mixtures of quinoline with alkanols have been determined from densities at 30°C as a function of composition. The excess volumes are negative over the whole mole fraction range for all the mixtures and decrease with increasing length of alkanol (C1–C10). The VE data have been analyzed in terms of an approach which uses graph theoretical connectivity parameters of the third degrees for two components. The analysis gives information regarding associated species in the pure state and in the mixture. It is suggested that, in the mixture state, no change occurs in the association of alkanols. 相似文献
10.
The transformation of gibbsite have been studied under hydrothermal influence. Results of the X-ray diffraction analysis of the samples heated at different temperatures from 170°C to 265°C are also discussed in detail. The percentage of the boehmite phase formed, due to the transformation of the gibbsite, have been determined by comparing the intensity of the most strongest reflection of the boehmite phase with a fully transformed sample. The activation energy value calculated form X-ray diffractograms is almost comparable with the value calculated from main DTA endotherm of gibbsite.Es wurde die Umwandlung von Gibbsit unter hydrothermalem Einfluß untersucht. Weiterhin werden auch Ergebnisse der Röntgendiffraktionsanalyse an den bei verschiedenen Temperaturen zwischen 170°C und 265°C erhitzten Proben besprochen. Durch Vergleich der Intensität der stärksten Reflexion der Böhmitphase mit einer vollständig umgewandelten Probe wurde der prozentuelle Anteil der während der Umwandlung von Gibbsit gebildeten Böhmitphase bestimmt. Der Wert für die Aktivierungsenergie, berechnet aus den Röntgendiffraktogrammen ist annähernd vergleichbar mit dem aus der DTA von Gibbsit berechneten Wert.
RRL Contribution No. 2028. 相似文献
RRL Contribution No. 2028. 相似文献