Salt concentration dependence

In equation (C2.6.14) it can be seen that tire required salt concentration depends strongly on tire valency of tire ions... 

Sakurai K, Iguchi R, Mizu M et al (2003) Polysaccharide-polynucleotide complexes. Part 7. Hydrogen-ion and salt concentration dependence of complexation between schizophyllan and single-stranded homo RNAs. Bioorg Chem 31(3) 216-226... 

An example of a calculation of the salt concentration dependence of the CMC on the basis of Eq. (6.13) is shown in Fig. 6.2. A fair agreement between theory and experiment is observed using only one adjustable parameter which fixes the absolute value of the calculated CMC. The slope (=. 73) of the approximately straight line is... 

Addition of salt leads to an additional screening of the Coulomb interaction [28, 32]. Our calculations for a multicomponent (polymer counterions salt) and a two component system (polymer counterions) demonstrate that the correlation functions can very well be described using the De-bye-Hiickel potential with a salt concentration dependent screening length. The effective potentials, however, strongly depend on the salt concentration. The counterion-counterion potential is weaker, whereas the monomer-monomer potential is stronger. The latter is a consequence of salt ion condensation on the polymer chain. 

Analyte ion association (pH and salt concentration-dependent process)... 

A number of PS II inhibitor treatments, such as Tris-washing and NH2OH extraction, had been well established as releasing Mn from the OEC [109]. Aker-lund, Andersson and co-workers showed that these treatments also released the peripheral polypeptides [71]. Mathis and co-workers showed that the ns phases in P-680 reduction that occur in untreated preparations are replaced by fxs components in inhibited samples [180]. The predominant decay phase is pH dependent, =2 ijs at pH 8 and =45 /is at pH 5, and is attributed to P-680 reduction by a secondary donor, usually designated D in optical work, which is identical to the EPR-detectable Z species [180,194,195]. The bulk pH and salt concentration dependencies of this phase implicate local membrane pH in influencing its time course... 

Matsuoka, H., Harada, T., Kago, K., and Yamaoka, H. Exact evaluation of the salt concentration dependence of interparticle distance in colloidal crystals by ultra-small-angle x-ray scattering. 2. the universality of the maximum in the interparticle distance salt concentration relationship. Langmuir, 1996,12, No. 23, p. 5588-5594. 

These results show that the solubility of polyelectrolytes in the presence of multivalent salt, especially at high salt concentration, depends on the relative affinity between charged groups of the polyelectrolyte and counterions. With organic multivalent cations, as spermidine and spermine, where... 

Actomyosin threads made from actomyosin which has been repeatedly precipitated contain no other proteins, and the salt concentration depends only on the composition of the bath. Those contractile properties which are common both to the extracted muscle fiber (fiber model) and the actomyosin thread (thread model) can therefore be ascribed to the actomyosin. 

Distribution of ions around a solute can be deduced from the frequency shift in characteristic vibrational modes of the solute upon increasing the salt concentration in solution. Such measurements with Raman-MCR (multi-curve resolution) technique were performed by Een-Amotz and co-workers for low-concentration TEA aqueous solutions at various concentrations of Nal and NaF [37]. These measurements show no frequency shift in CH stretch region of TEA in a presence of NaF, in agreement with EFP simulations showing no fluoride ions in proximity of TEA. On the other hand, there is a small reproducible red shift in CH stretch vibration in Nal solutions, with a magnitude of 1 cm /M. That is, a total shift of 3 cm in a 3M Nal solution was observed. The QM/EFP scheme, in which TEA and iodide ions were described by MP2/6-311-I—l-G and water molecules were represented by effective fragments, was used to reproduce this salt concentration dependent frequency shift. For that, 100 snapshots from the EFP... 

Na Cs whereas Li does not induce any change. This stability order is confirmed by the salt concentration dependence of the fluorescence polarization. Furthermore, Na NMR spectroscopy reveals that the product system is stabilized by the addition of cations, suggesting that the OH group in schizophyllan and the phosphate anion in poly(U) synergistically form a specific ligand system for the cations. 

For the upper boundary of this regime, see discussion below.) In this regime, the chain size shows slightly stronger salt concentration dependence Re ... 

Equation [210] explains the minimum in salt concentration dependence of the solution viscosity of weakly charged polyampholytes with/= 0.2 and 0.3 at salt concentration Cs = 0.1M NaCl observed by McCormick and Salazar. ... 

Fig. 2 Salt concentration dependence of the decay length (Do) of the long-range attraction between amine-modified surfaces. Data were taken for samples exhibiting attraction at different pHs (pis ) pH 9 (1), pH 5.6 (m and n), pH 6 (o). Debye length is also included as a reference (dotted line)...

Whereas for the adsorption of strong polyelectrolytes there is a distinct salt concentration dependence, the ionic strength is much less important for weak polyelectrolytes, which are characterized by a pH-dependent charge density. The reason is that weak polyelectrolytes can adjust their degree of dissociation in order to compensate the surface charge more effectively. As a result, the substrate-adsorbate complex is virtually neutral, which renders the effect of the salt concentration relatively unimportant. Such small ionic strength dependence for weak polyelectrolytes has indeed been found, both theoretically and experimentally. ... 

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