Calcium cation properties

Application of the reaction to the 2-azidobenzoyl derivative of diethylene glycol monomethyl ether 92, in a mixture of tetrahydrofuran and diethylene glycol monomethyl ether as the nucleophile, affords 2-(2-methoxyethoxy)ethyl 2-[2-(2-methoxyethoxy)ethoxy]-37/-azepine-3-carbo-xylate (93), which displays metal cation complexing properties towards lithium, potassium, and. to a lesser extent, barium and calcium cations.198... 

Positively charged ion in aqueous solution such as hydrogen (H+) or calcium (Ca2+) ions. Certain chemicals may therefore be cationic and exhibit cationic properties. 

Pectins are best known for their ability to form gels (6), a property which often involves intermolecular binding mediated by calcium cations (7). The principal commercial use of pectin is in the preparation of jelly and jam products (8). Pectins provide firmness in fresh fruits and vegetables (9-11). Historically, natural tobacco pectins also have been used as binders to prepare reconstituted sheets from tobacco by-products that are then incorporated into cigarette filler or cigar wrappers (12-14). 

The discovery of the calcium-transporting properties of lasalocid and A-23187 has prompted numerous studies concerning their physiological activities they were shown to be potential cardiovascular agents. Although clinical apph-cations have been hampered by their potential toxicity, almost all of these antibiotics have become particularly important as coccidiostatics for poultry industries. 

Orthophosphate salts are generally prepared by the partial or total neutralization of orthophosphoric acid. Phase equiUbrium diagrams are particularly usehil in identifying conditions for the preparation of particular phosphate salts. The solution properties of orthophosphate salts of monovalent cations are distincdy different from those of the polyvalent cations, the latter exhibiting incongment solubiUty in most cases. The commercial phosphates include alkah metal, alkaline-earth, heavy metal, mixed metal, and ammonium salts of phosphoric acid. Sodium phosphates are the most important, followed by calcium, ammonium, and potassium salts. 

Many other metal thiosulfates, eg, magnesium thiosulfate [10124-53-5] and its hexahydrate [13446-30-5] have been prepared on a laboratory scale, but with the exception of the calcium, barium [35112-53-9] and lead compounds, these are of Httle commercial or technical interest. Although thaHous [13453-46-8] silver, lead, and barium thiosulfates are only slightly soluble, other metal thiosulfates are usually soluble in water. The lead and silver salts are anhydrous the others usually form more than one hydrate. Aqueous solutions are stable at low temperatures and in the absence of air. The chemical properties are those of thiosulfates and the respective cation. 

Nerve growth factor snake venoms zinc, 6, 613 Neurospora crassa calcium transport, 6, 571 cation transport, 6, 559 Neurosporin, 6, 676 Neurotransmitters secretion calcium, 6, 595 Neutral complexes electrical properties, 6, 143 Neutron absorbers... 

Even when modifiers are not necessary for cement formation, they can lead to improved cement properties. Kingery (1950b) also examined this effect. He found that optimum bonding was achieved with cations that had small ionic radii and were amphoteric or weakly basic, such as beryllium, aluminium, magnesium and iron. By contrast, cations that were highly basic and had large ionic radii, for example calcium, thorium and barium, had a detrimental effect on bonding. 

Heparin is most commonly prepared as the sodium salt, which can be converted into other salts (usually potassium or calcium) by cation exchange.45 For the sake of simplicity, the term heparin will be used throughout this article, instead of the more appropriate term sodium heparinate. Mention of a specific cation other than sodium will be made only when relevant to the property discussed. 

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