Dendritic salt

Dendritic polymers, fullerene, 12 252 Dendritic salt, 22 805 Dendritic siloxanes, synthesis of, 22 554 Dendrobine, 2 102... 

Food-grade dendritic salt, which is porous, can be used as an absorbent for liquid medications, and as a tablet diluent in specific formulations. 

Other support materials of minor importance include various fluorocarbon powders, glass beads, carbon, and dendrite salts. Fluorocarbon powders are used primarily for the separation of reactive compounds that would destroy or be destroyed by other materials. A low surface energy and electrostatic properties make fluorocarbon powders difficult to coat and pack into columns. Because of their controlled shape, glass beads are used mainly for theoretical studies but have a low loading capacity and an active surface. 

A structurally different form of ordinary table salt (sodium chloride NaCl). Normally table salt crystals are cubes. Dendritic crystals are branched or star-like, hence the term dendritic. The following advantages are listed for dendritic salt lower bulk density, rapid solution, and an unusual capacity for absorbing moisture before becoming wet. 

A number of attempts to produce tire refractory metals, such as titanium and zirconium, by molten chloride electrolysis have not met widr success with two exceptions. The electrolysis of caesium salts such as Cs2ZrCl6 and CsTaCle, and of the fluorides Na2ZrF6 and NaTaFg have produced satisfactoty products on the laboratory scale (Flengas and Pint, 1969) but other systems have produced merely metallic dusts aird dendritic deposits. These observations suggest tlrat, as in tire case of metal deposition from aqueous electrolytes, e.g. Ag from Ag(CN)/ instead of from AgNOj, tire formation of stable metal complexes in tire liquid electrolyte is the key to success. 

After the end of the interaction, the melt is cooled down to room/ambient temperature, and the metal and salts are crushed and leached using mineral acids and water to separate the metal. The metal precipitates mostly in the form of dendrites, which are pressed and sintered into bars to be converted into wire, sheet and powder. 

Koshina et al. have reported that there are three kinds of morphology [40] dendritic, granular and mossy. Mossy lithium is formed when the deposition current is small and the salt concentration is high. This mossy lithium provides a high cycling efficiency. 

Aqueous electrolytes proposed in the literature for cathodic electrodeposition of lead selenide are generally composed of dissolved selenous anhydride and a lead salt, such as nitrate or acetate. Polycrystalline PbSe films have been prepared by conventional electrosynthesis from ordinary acidic solutions of this kind on polycrystalline Pt, Au, Ti, and Sn02/glass electrodes. The main problem with these applications was the PbSe dendritic growth. Better controlled deposition has been achieved by using EDTA in order to prevent PbSeOs precipitation, and also acetic acid to prevent lead salt hydrolysis. 

The composition of the electrolyte is quite important in controlling the electrolytic deposition of the pertinent metal, the chemical interaction of the deposit with the electrolyte, and the electrical conductivity of the electrolyte. In the case of molten salts, the solvent cations and the solvent anions influence the electrodeposition process through the formation of complexes. The stability of these complexes determines the extent of the reversibility of the overall electroreduction process and, hence, the type of the deposit formed. By selecting a suitable mixture of solvent cations to produce a chemically stable solution with strong solute cation-anion interactions, it is possible to optimize the stability of the complexes so as to obtain the best deposition kinetics. In the case of refractory and reactive metals, the presence of a reasonably stable complex is necessary in order to yield a coherent deposition rather than a dendritic type of deposition. 

One of the first results on the use of phosphine dendrimers in catalysis was reported by Dubois and co-workers [16]. They prepared dendritic architectures containing phosphorus branching points which can also serve as binding sites for metal salts. These terdentate phosphine-based dendrimers were used to incorporate cationic Pd centers in the presence of PPh3. Such cationic metalloden-dritic compounds were successfully applied as catalysts for the electrochemical reduction of C02 to CO (e.g. 9, Scheme 9) with reaction rates and selectivities comparable to those found for analogous monomeric palladium-phosphine model complexes suggesting that this catalysis did not involve cooperative effects of the different metal sites. 

Lin Y, Liao Q, Jin X. Molecular dynamics simulations of dendritic polyelectrolytes with flexible spacers in salt free solution. J Phys Chem B 2007 111 5819-5828. 

Pyridine-based ligands which have been used for dendrimers are 2,2-bipyridine (bpy) 17,2,3-bis(2-pyridyl)pyrazine (2,3-dpp) 18 and its monomethylated salt 19, and 2,2 6, 2"-terpyridine 20. Their transition metal complexes possessing dendritic structures were first reported in the collaborative work of Denti, Campagne, and Balzani whose divergent synthetic strategy has led to systems containing 22 ruthenium centers. - The core unit is [Ru(2,3-dpp)3] 21 which contains three... 

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