Einfluß der Füllung auf das extraktionschromatographische Verhalten Seltener Erden im System Di-(2-äthylhexyl)-phosphorsäure-Chromosorb-Salzsäure

The effect of saturation of the support with extractant on the height equivalent to a theoretical plate and capacity was studied from 0.25 to 1 g Di-(2-ethylhexyl)phosphoric acid per gram Chromosorb. The results were obtained in the case of high loading with Rare Earths in the column.     

Poröse Struktur der Polyarylate

Ohne Zusammenfassung     

Über das extraktions-chromatographische Verhalten des Neodyms bei höherer Beladung

The effect of HCl concentration in the mobile phase on the extraction chromatographic behavior of Nd with high column loading was investigated. Significant differences in Nd behavior at low and high HCl concentration were established.     

The thermodynamic properties and solvation of ammonium bromide,iodide, and nitrate in methylpyrrolidone at 298.15 K

The heat capacity and density of solutions of ammonium bromide, iodide, and nitrate in methylpyrrolidone (MP) were studied calorimetrically and densimetrically at 298.15 K. The standard partial molar heat capacities and volumes (\(\overline {C_{p_2 }^O } \) and \(\overline {V_2^O } \)) of the electrolytes in MP were calculated. The standard heat capacities \(\overline {C_{p_i }^O } \) and volumes \(\overline {V_i^O } \) of the nitrate and ammonium ions in MP were determined. The mean coordination numbers of the NH ₄ ⁺ and NO ₃ ^? ions in a solution in MP at 298.15 K were calculated.     

Permutation binomials and their groups

This paper is devoted to studying the properties of permutation binomials over finite fields and the possibility to use permutation binomials as encryption functions. We present an algorithm for enumeration of permutation binomials. Using this algorithm, all permutation binomials for finite fields up to order 15000 were generated. Using this data, we investigate the groups generated by the permutation binomials and discover that over some finite fields \mathbb F_q {{\mathbb F}_q} , every bijective function on [1..q − 1] can be represented as a composition of binomials. We study the problem of generating permutation binomials over large prime fields. We also prove that a generalization of RSA using permutation binomials is not secure. Bibliography: 9 titles.     

Ultra small Gd(2)O(3) nanoparticles: Absorption and emission properties

In this paper, we report a facile method for synthesis of ultra small (1-3nm) gadolinium oxide (Gd(2)O(3)) nanoparticles using citric acid (CA) as a capping agent. The dependence of nanoparticle (NP) size on the ratio between CA and gadolinium (Gd) is investigated. Absorption properties of the ultra small Gd(2)O(3) NPs in UV region have four characteristic peaks at 312nm, 274nm, 253nm and 228nm. Finally, we show that the Gd(2)O(3) nanoparticles synthesized by this method induce triplet emission (phosphorescence) from CA and EG in the NIR region.     

Fluorescence Study of Lipid Bilayer Interactions of Eu(III) Coordination Complexes

The interaction between Eu(III) tris-β-diketonato coordination complexes (EC), displaying antitumor activity, and lipid vesicles composed of zwitterionic lipid phosphatidylcholine has been studied using fluorescence spectroscopy techniques. To characterize EC-membrane binding, several fluorescent probes, including pyrene, Prodan and 1,6-diphenyl-1,3,5-hexatriene, have been employed. It has been found that EC display effective partitioning into lipid phase, giving rise to structural modifications of both polar and nonpolar lipid bilayer regions, viz. enhancement of membrane hydration and increase in tightness of lipid chain packing. The fact that EC accumulating in lipid bilayer are incapable of inducing significant disruption of membrane structural integrity creates strong prerequisites for development of liposomal nanocarriers of these potential antitumor drugs. Such a possibility is also corroborated by the observation that EC membrane incorporation does not prevent lipid bilayer partitioning of long-wavelength squaraine dyes which represent promising candidates for visualization of liposome biodistribution.     

Peculiarities of the B8-Solid Solution Formation in Ni(Sb,Sn) and Co(Sb,Sn) Systems Studied by Mossbauer Effect Method

Quadrupole splitting and effective characteristic temperatures of ¹¹⁹Sn in Ni(Sb,Sn) and Co(Sb,Sn) solid solutions with B8-type structure have been studied by Mossbauer Effect method. The electric field gradient at metalloid atoms was estimated in point charge model for different variants of local environment. On the basis of the comparison between experimental Quadruple Splitting values and estimated Electric Field Gradient ones it was concluded that MeII-Sn pairs occur more often than MeII-Sb when the amount of transition metal in ditrigonal-dibipyramidal positions is less than 0.10.