Biomedical subjects

Kelei Zhuo

Publications and source records attributed to Kelei Zhuo.

4 recordsLinked to original sources

PubMed2005

Thermodynamics of the interaction of RbCl with some monosaccharides (D-glucose, D-galactose, D-xylose, and D-arabinose) in aqueous solutions at 298.15K.

The Gibbs energy interaction parameters of RbCl with some monosaccharides (D-glucose, D-galactose, D-xylose, and D-arabinose) in water, g(ES), were obtained from electromotive force (emf) measurements of the electrochemical cell without liquid junction and containing two ion-selective electrodes (ISE): K-ISEmid R:RbCl(m(E))mid R:ISE-Cl and K-ISEmid R:RbCl(m(E)),saccharide (m(S))mid R:ISE-Cl, at 298.15K. The enthalpy interaction parameters of RbCl with these monosaccharides in water, h(ES), are determined according to the McMillan-Mayer theory from the measurements of the enthalpies of mixing of aqueous RbCl solutions with aqueous monosaccharide solutions, as well as the enthalpies of dilution of RbCl and monosaccharide solutions in pure water at 298.15K by a calorimetric method. Furthermore, the entropy interaction parameters, s(ES), can be evaluated through g(ES) and h(ES). The results suggest that the electrostatic interactions of these monosaccharides with RbCl in water are predominant compared with structural interactions, and these parameters are controlled primarily by the stereochemical structure of the monosaccharides in water.

Arabinose↗

PubMed2005

Activity coefficients and thermodynamic parameters for RbCl/CsCl + amide (acetamide, propanamide, and n-butanamide) + water system at 298.15 K.

Electromotive force (emf) of the chemical cell without liquid-junction K-ISE | RbCl/CsCl ( m(E)) | ISE-Cl and K-ISE | RbCl/CsCl (m(E)), amide (m(N)) | ISE-Cl, have been measured at 298.15 K, where m(E)=(0.005 to 0.5) mol kg(-1) and m(N)= (0.05 to 3.0) mol kg(-1). The activity coefficients of RbCl/CsCl in amide (acetamide, propanamide, and n-butanamide) + water mixture can be obtained from these electromotive force data and in the mean time the Gibbs free energy interaction parameters of RbCl/CsCl + amide pair in water, g(EN), as well as the salt constant, k(S), can be evaluated. The results show that both g(EN)>0, k(S)>0 at 298.15 K, and all the activity coefficients of electrolyte in amide + water mixture increase with increasing the m(N), but it is a little complicated for the dependence of activity coefficients on m(E). These thermodynamic parameters were discussed in terms of a model of the structural interaction and electrostatic interaction and the dependence of them on the number of carbon atoms in amide as well as the radius of metal ions were interpreted by the group additivity principle.

Acetamides↗

PubMed2005

Thermodynamic pair interaction parameters on various concentration scales.

Derivations are given for the relationships of the conversions of thermodynamic pair interaction parameters on various concentration scales. A comparison is made between the free energy pair interaction parameters obtained from different measurement methods or conversions, indicating that the values on the same concentration scale are in good agreement with each other.

Journal Article↗

PubMed2005

Interactions of nanosized Al2O3 and ZnO with poly(ethylene oxide)-NaSCN polymer electrolytes.

The effect of nanosized Al2O3/ZnO fillers on the interactions in PEO-NaSCN polymer electrolytes has been studied by FT-IR, XRD, and DTA measurements. The experimental results are discussed according to the grain boundary effect, the principle of Lewis acid-base, and epitaxial effect. It is shown that the hard Lewis acid centers on the surface of Al2O3 exhibit strong interactions with ether oxygens in PEO, even with ether oxygens that coordinated to Na+. Therefore, the modes of the interaction of Al2O3 with PEO-NaSCN electrolytes are dependent on the salt content. Al2O3 cannot influence the ionic association in P(EO)8NaSCN electrolyte, but do reduce significantly the solvating ability of PEO toward NaSCN in P(EO)60NaSCN electrolyte. However, NaSCN in P(EO)20NaSCN-30%Al2O3 nanocomposite appears as a state that resembles the situation of NaSCN in PEO amorphous phase. In contrast with Al2O3, the epitaxial effect of ZnO is not found in the interested systems where only weaker interaction is observed between ZnO and ether oxygen, and the modes of interaction of ZnO with PEO-NaSCN electrolytes are hardly related to the salt content. In addition, the soft Lewis acid groups on ZnO surface exhibit stronger complexation with SCN- in PEO-NaSCN electrolytes, and both can form the complex anion ZnO...SCN-.

Journal Article↗