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Jordi de Mier‐Vinu ngel M. Montaa Virtudes Moreno María J. Prieto 《无机化学与普通化学杂志》2005,631(11):2054-2061
Two 1,4‐diamine ligands were synthesized having 1,2‐bis(aminomethyl)‐cyclohexane and 1,2‐bis(aminomethyl)‐benzene structures. The two ligands have different electron density in the six‐membered ring: a cyclohexane versus a phenyl ring. The organic synthesis of the ligands was carried out by synthetic pathways of seven and four steps, respectively, starting from 1,2,3,6‐tetrahydrophthalic anhydride and diethyl phthalate. The coordination of platinum to these ligands afforded platinum(II) complexes which are analogue to the clinical drug cisplatin but form a seven‐membered chelate ring. The interaction of the platinum compounds with DNA was studied in order to know the relationship between the electron density of ligands and their capability to chelate DNA, by using three techniques: Circular Dichroism, Agarose Gel Electrophoresis and Atomic Force Microscopy. The degree of interaction of both compounds with DNA was slightly different, but both complexes showed a cisplatin‐like behaviour and are promising candidates to follow an extensive study of their cytotoxic activity. 相似文献
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Negatively buoyant jets consist in a dense fluid injected vertically upward into a lighter ambient fluid. The numerical simulation of this kind of buoyancy‐driven flows is challenging as it involves multiple fluids with different physical properties. In the case of immiscible fluids, it requires, in addition, to track the motion of the interface between fluids and accurately represent the discontinuities of the flow variables. In this paper, we investigate numerically the injection of a negatively buoyant jet into a homogenous immiscible ambient fluid using the Particle Finite Element Method and compare the two‐dimensional numerical results with experiments on the injection of a jet of dyed water through a nozzle in the base of a cylindrical tank containing rapeseed oil. In both simulations and experiments, the fountain inlet flow velocity and nozzle diameter have been varied to cover a wide range of Froude Fr and Reynolds Re numbers ( 0.1 < Fr < 30, 8 < Re < 1350), reproducing both weak and strong laminar fountains. The flow behaviors observed for the different numerical simulations fit in the regime map based on the Re and Fr values of the experiments, and the maximum fountain height is in good agreement with the experimental observations, suggesting that particle finite element method is a useful tool for the study of immiscible two‐fluid systems. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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F. Barbadillo A. Fuentes S. Naya R. Cao J. L. Mier R. Artiaga 《Journal of Thermal Analysis and Calorimetry》2007,87(1):223-227
The aim of this paper is to evaluate and explain the fitting of dynamic
TG curves by a mixture of logistic functions. This model assumes that more
than one physical process may be involved in each mass loss step and that
each physical process may extend along all the experiment. One of the main
sources of difficulties in TG is that, very often, different stages of decomposition
substantially overlap each other. Several real and simulated TG curves were
analysed in this paper. An optimal fitting of the TG curves was obtained by
a mixture of logistics. In many cases the optimal fitting reproduces accurately
the TG curve. Accordingly, the TG curve can be understood as a sum of parallel
reactions, where each single reaction is represented by one or a small number
of logistic components. Additionally, making use of the analytical derivative
of the fitting, a mixture of Arrhenius reaction order equations was applied
to the same curves. In all the cases, the fitting obtained with the mixture
of Arrhenius was worse than the obtained with the mixture of logistics. A
software was developed to automatically perform these tasks. The physical
meaning of the fitting was explained. 相似文献
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Anna de Mier 《Discrete Mathematics》2005,301(1):57-65
We prove that if a graph H has the same Tutte polynomial as the line graph of a d-regular, d-edge-connected graph, then H is the line graph of a d-regular graph. Using this result, we prove that the line graph of a regular complete t-partite graph is uniquely determined by its Tutte polynomial. We prove the same result for the line graph of any complete bipartite graph. 相似文献
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Peptide-based molecular probes identified by bacteriophage (phage) display technology expand the peptide repertoire for in vivo diagnosis and therapy of cancer. Numerous peptides that bind cancer-associated antigens have been discovered by panning phage libraries. However, until now only few of the peptides selected by phage display have entered clinical applications. The success of phage derived peptides essentially depends on the quality of the library screened. This review summarizes the methods to achieve highly homogenous libraries that cover a maximal sequence space. Biochemical and chemical strategies for the synthesis of DNA libraries and the techniques for their integration into the viral genome are discussed in detail. A focus is set on the methods that enable the exclusion of disturbing sequences. In addition, the parameters that define the variability, the minimal numbers of copies per library and the use of alternating panning cycles to avoid the loss of selected hits are evaluated. 相似文献
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G. de Jongh MIEKE BERGERS J. B. M. Boezeman A. R. Verhagen P. D. Mier 《Photochemistry and photobiology》1984,39(5):625-629
Abstract— The lethal effect of UVA and PUVA radiation was studied in cultures of fresh and mature monocytes. UVA radiation alone was shown to possess a lethal effect at doses which are attained in the dermis in vivo. The synergistic action of 8-methoxypsoralen and UVA radiation predominated in PUVA radiation, but again a residual effect of UVA alone was demonstrated mathematically. Mature cells were less sensitive than fresh monocytes.
Our results indicate that a monolayer culture of non-dividing, mesenchymal cells offers considerable advantages over in vivo systems as a model for the study of phototoxicity. 相似文献
Our results indicate that a monolayer culture of non-dividing, mesenchymal cells offers considerable advantages over in vivo systems as a model for the study of phototoxicity. 相似文献
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Henry Insuasty Paola Mier Gina Suarez John N. Low Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(1):o27-o30
The molecular dimensions of 2‐ethylsulfanyl‐7‐(4‐methylphenyl)‐4‐phenylpyrazolo[1,5‐a][1,3,5]triazine, C20H18N4S, (I), 7‐(4‐chlorophenyl)‐2‐ethylsulfanyl‐4‐phenylpyrazolo[1,5‐a][1,3,5]triazine, C19H15ClN4S, (II), and 4,7‐bis(4‐chlorophenyl)‐2‐(ethylsulfanyl)pyrazolo[1,5‐a][1,3,5]triazine, C19H14Cl2N4S, (III), show evidence for some aromatic delocalization in the pyrazole rings. The conformations adopted by the ethylsulfanyl substituents are different in all three compounds. There are no hydrogen bonds in any of the crystal structures, but pairs of molecules in (II) and (III) are linked into centrosymmetric dimers by π‐stacking interactions. 相似文献
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