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排序方式: 共有485条查询结果,搜索用时 15 毫秒
481.
We have recently investigated the aggregation behavior of zwitterionic n-dodecyl phosphocholine in the presence of high salt. As double logarithmic Corrin-Harkins plots of the critical micellar concentration versus the salt concentration were not linear, here we re-examine those data in the context of the binding model of surfactant aggregation, as previously developed by us for ionic surfactants. We have also re-examined plenty of data available in the literature on the salt-dependent aggregation of neutral surfactants. The use of double-logarithmic plots allowed us to show that the binding model is of general applicability. Indeed, it permits unified treatment of ionic and uncharged aggregation without requiring the introduction of linear terms in the salt concentration, as needed in the empirical Corrin-Harkins treatment of nonionic surfactants. The use of this model could be of help in a broad range of surfactant-based applications in the presence of high salt. 相似文献
482.
We have investigated the effect of ionic strength on the aggregation behavior of n-dodecyl phosphocholine. On the basis of the classical Corrin–Harkins relation, the critical micellar concentration of this
detergent decreases with a biphasic trend on lithium chloride addition. It is nearly constant below 150 mM salt, with a mean
value of 0.91 mM, whereas it undergoes a dramatic 80-fold decrease in 7 M LiCl. Such a drop in the critical micellar concentration
could be explained by the effect of salting out and the implication of phosphocholine head groups on the organization of surrounding
water. Knowledge of the effective critical micellar concentration of n-dodecyl phosphocholine could be useful in the purification of membrane proteins in non-denaturing conditions. 相似文献
483.
Alessandro Michelangeli Alessandro Olgiati Raffaele Scandone 《Journal of Nonlinear Mathematical Physics》2018,25(4):558-588
We establish the local and global theory for the Cauchy problem of the singular Hartree equation in three dimensions, that is, the modification of the non-linear Schrödinger equation with Hartree non-linearity, where the linear part is now given by the Hamiltonian of point interaction. The latter is a singular, self-adjoint perturbation of the free Laplacian, modelling a contact interaction at a fixed point. The resulting non-linear equation is the typical effective equation for the dynamics of condensed Bose gases with fixed point-like impurities. We control the local solution theory in the perturbed Sobolev spaces of fractional order between the mass space and the operator domain. We then control the global solution theory both in the mass and in the energy space. 相似文献
484.
Raffaele Mezzenga Louis Boogh Bo Pettersson Jan‐Anders E. Mnson 《Macromolecular Symposia》2000,149(1):17-22
The morphology build‐up in toughened epoxy blends using reactive hyperbranched dendritic polymers (HBP) and amine‐cured epoxy resins has been investigated in the present work. By changing the processing conditions or the surface chemistry of the modifier, very different morphologies can be obtained, ranging from homogeneous blends to coarse two‐phase systems. The morphology characterised by electron and optical microscopy has been interpreted combining constitutive equations for phase separation and thermodynamic modelling of phase interactions. The latter model, based on the Flory‐Huggins lattice theory, was modified in order to take into account the addition reactivity of the HBP modifiers. This approach proved successful and can be used as a tool for final morphology prediction in any reactive blend formulation. 相似文献
485.