Uranyl ion complexes with long chain aminoalcoholbis(phenolate) [O,N,O,O′] donor ligands

Polyhedron ◽  
2007 ◽  
Vol 26 (1) ◽  
pp. 184-196 ◽  
Author(s):  
Harri Sopo ◽  
Ari Väisänen ◽  
Reijo Sillanpää
Keyword(s):  
Uranyl Ion ◽  
Donor Ligands ◽  
Long Chain

Uranyl ion complexes with aminoalcoholbis(phenolate) [O,N,O,O′] donor ligands

Polyhedron ◽  
2006 ◽  
Vol 25 (5) ◽  
pp. 1223-1232 ◽  
Author(s):  
Harri Sopo ◽  
Jukka Sviili ◽  
Arto Valkonen ◽  
Reijo Sillanpää
Keyword(s):  
Uranyl Ion ◽  
Donor Ligands

Uranyl Ion Complexes with Long-Chain Aliphatic α,ω-Dicarboxylates and 3d-Block Metal Counterions

2016 ◽  
Vol 55 (5) ◽  
pp. 2133-2145 ◽  
Author(s):  
Pierre Thuéry ◽  
Jack Harrowfield
Keyword(s):  
Uranyl Ion ◽  
Long Chain

Synergistic extraction of uranyl ion with β-diketones and sulphoxides

1973 ◽  
Vol 26 (1) ◽  
pp. 77 ◽  
Author(s):  
MS Subramanian ◽  
SA Pai
Keyword(s):  
Equilibrium Constant ◽  
Uranyl Ion ◽  
Synergistic Extraction ◽  
Synergistic Enhancement ◽  
Different Temperatures ◽  
Base Strength ◽  
Entropy Factor ◽  
Enthalpy And Entropy ◽  
Long Chain ◽  
Synergistic Reaction

Distribution measurements of the synergistic extraction of uranyl ion with β-diketones and sulphoxide donors indicate that the long-chain aliphatic sulphoxides are ten times more powerful as synergists than the aromatic sulphoxides. Methods of estimating the relative base strength of the donors by i.r. and N.M.R. studies of the donor hydrates are described and the results have been correlated with the equilibrium constant of the synergistic reaction. For a given sulphoxide donor, the synergistic enhancement seems to be affected by the various substituents changing the acidity of the β-diketone. From the values of enthalpy and entropy factors derived for these systems by distribution measurements at different temperatures, the greater stability of the complexes with aliphatic sulphoxide donors has been attributed to the entropy factor.

Polymer Morphology Revealed by Staining Techniques

1981 ◽  
Vol 39 ◽  
pp. 340-341
Author(s):  
A. C. Reimschuessel ◽  
V. Kramer
Keyword(s):  
Polymer Melt ◽  
Nylon 6 ◽  
Morphological Features ◽  
Negative Staining ◽  
Polymer Morphology ◽  
Crystallizable Polymer ◽  
Staining Techniques ◽  
Long Chain

Staining techniques can be used for either the identification of different polymers or for the differentiation of specific morphological domains within a given polymer. To reveal morphological features in nylon 6, we choose a technique based upon diffusion of the staining agent into accessible regions of the polymer.When a crystallizable polymer - such as nylon 6 - is cooled from the melt, lamellae form by chainfolding of the crystallizing long chain macromolecules. The regions between adjacent lamellae represent the less ordered amorphous domains into which stain can diffuse. In this process the lamellae will be “outlined” by the dense stain, giving rise to contrast comparable to that obtained by “negative” staining techniques.If the cooling of the polymer melt proceeds relatively slowly - as in molding operations - the lamellae are usually arranged in a radial manner. This morphology is referred to as spherulitic.

A theory of contamination in electron microscopes by surface diffusion

1978 ◽  
Vol 36 (1) ◽  
pp. 116-117
Author(s):  
J.T. Fourie
Keyword(s):  
Electron Beam ◽  
Surface Diffusion ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Physical Parameters ◽  
Carbon Compounds ◽  
Hydrocarbon Molecules ◽  
Electron Microscopes ◽  
Primary Electrons ◽  
Long Chain

Contamination in electron microscopes can be a serious problem in STEM or in situations where a number of high resolution micrographs are required of the same area in TEM. In modern instruments the environment around the specimen can be made free of the hydrocarbon molecules, which are responsible for contamination, by means of either ultra-high vacuum or cryo-pumping techniques. However, these techniques are not effective against hydrocarbon molecules adsorbed on the specimen surface before or during its introduction into the microscope. The present paper is concerned with a theory of how certain physical parameters can influence the surface diffusion of these adsorbed molecules into the electron beam where they are deposited in the form of long chain carbon compounds by interaction with the primary electrons.

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