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Alain Miranville Ramon Quintanilla 《Mathematical Methods in the Applied Sciences》2016,39(15):4385-4397
Our aim in this paper is to study generalizations of the nonconserved and conserved Caginalp phase‐field systems based on the Maxwell–Cattaneo law with two temperatures for heat conduction. In particular, we obtain well‐posedness results and study the dissipativity of the associated solution operators. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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The relative aromaticity of benzenoid rings in the linear polyacenes is investigated using two novel aromaticity approaches. According to the first, the aromaticity of individual benzene rings was gauged by the values of six-center bond indices (SCI) calculated within the so-called Generalized Population Analysis (GPA). In the second approach, the same goal is addressed using the theory of Molecular Quantum Similarity (MQS). Both independent approaches are found to correlate very well, and both point toward decreasing aromaticity in any linear polyacenes upon going from the outer to inner rings. 相似文献
126.
Humic acid (HA) solutions provide an unexpected medium for direct fabrication of gold nanoparticles (HA-AuNP) and a clear window for surface-enhanced Raman scattering (SERS) with many potential applications in the ultrasensitive chemical analysis of environmental pollutants. It is demonstrated that the HA-AuNP fabrication can be easily achieved in a wide range of pH (2 to 12). The background SERS spectra of HA is relatively weak in absolute intensity, allowing the detection of the enhanced Raman signal from trace amount of contaminants. An in-situ approach is illustrated where the HA-AuNP fabrication is carried out with a HA solution containing the target pollutant. The technique may allow for the direct detection of organic pollutants present in the humic fraction of soil. 相似文献
127.
DNA polymerase fidelity is of immense biological importance due to the fundamental requirement for accurate DNA synthesis in both replicative and repair processes. Subtle hydrogen-bonding networks between DNA polymerases and their primer/template substrates are believed to have impact on DNA polymerase selectivity. We show that deleting defined interactions of that kind by rationally designed hydrophobic substitution mutations can result in a more selective enzyme. Furthermore, a single-atom replacement within the DNA substrate through chemical modification, which leads to an altered acceptor potential and steric demand of the DNA substrate, further increased the selectivity of the developed systems. Accordingly, this study about the impact of hydrophobic alterations on DNA polymerase selectivity--enzyme and substrate wise--further highlights the relevance of shape complementary and polar interactions on DNA polymerase selectivity. 相似文献
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Pericet-Camara R Cahill BP Papastavrou G Borkovec M 《Chemical communications (Cambridge, England)》2007,(3):266-268
Weakly charged solid substrates can be nano-patterned in liquid-like order with large and well-defined spacing by adsorbing poly(amido amine) (PAMAM) dendrimers; highly charged substrates lead to lower spacing due to electrostatic three-body attractions between the dendrimers and the substrate. 相似文献
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Ibrahem I Rios R Vesely J Zhao GL Córdova A 《Chemical communications (Cambridge, England)》2007,(8):849-851
The highly chemo- and enantioselective organocatalytic tandem reaction between N-protected hydroxyl amines and alpha,beta-unsaturated aldehydes is presented; the reaction provides access to 5-hydroxyisoxazolidines and beta-amino acids in high yields and with 90-99% ee. 相似文献