Ionic water

In general, the compounds best separated by LSC are those which are soluble in organic solvents and are non-ionic. Water soluble non-ionic compounds are better separated using either reverse-phase or bonded-phase chromatography. 

In general, binary compounds of two nonmetals are molecular, whereas binary compounds formed by a metal and a nonmetal are ionic. Water (H20) is an example of a binary molecular compound, and sodium chloride (NaCl) is an example of a binary ionic compound. As we shall see, these two types of compounds have... 

DC Harsh, SH Gehrke. Characterization of ionic water absorbent polymers Determination of ionic content and effective crosslink density. In L Brannon-Peppas, RS Harland, eds. Absorbent Polymer Technology. Amsterdam Elsevier, 1990, pp 103-124. 

Average treatment volume was 600 gallons. All fluids contained 1% (by volume) of water wetting non-emulsifier. The treatments utilizing a cationic organic polymer included the polymer in all aqueous based fluids. The reported polymer concentration of one percent by volume of the aqueous polymer solution as supplied. Active polymer concentration is actually less than this. When the clay stabilization polymer was part of the well treatment, a non-ionic water wetting nonemulsifier was used. 

UV data for the non-ionic water-soluble polysilane 41 (see Section 3.11.4.2.1.(0) were recorded in 20 different solvents.149 Selected spectra are shown in Figure 17. 

The behaviour of ternary systems consisting of two polymers and a solvent depends largely on the nature of interactions between components (1-4). Two types of limiting behaviour can be observed. The first one occurs in non-polar systems, where polymer-polymer interactions are very low. In such systems a liquid-liquid phase separation is usually observed each liquid phase contains almost the total quantity of one polymer species. The second type of behaviour often occurs in aqueous polymer solutions. The polar or ionic water-soluble polymers can interact to form macromolecular aggregates, occasionally insoluble, called "polymer complexes". Examples are polyanion-polycation couples stabilized through electrostatic interactions, or polyacid-polybase couples stabilized through hydrogen bonds. 

This chapter is limited to compounds in group 2 of both classifications, that is, polar, even ionic, water-soluble compounds of MW < 500 that are less lipid-soluble than those of group 1. These polar compounds, in most cases, are volatile enough for GC separation or can be made volatile enough by derivatization. However, some of MW < 500 are still not volatile enough for GC under any conditions these must be separated by HPLC. These compounds are covered elsewhere in this book (2). 

Kulicke W-M (1986) Unusual instability effects observed in ionic and non-ionic water soluble polymers Makromol Chem, Macromol Symp 2 137... 

Ionic water-soluble compounds can be retained by ion-exchange sorbents or by reversed-phase (RP) sorbents if ionization is controlled by ion suppression (i.e., by pH control that produces the nonionized form). In ion-exchange SPE, retention occurs at a sample pH at which the analyte is in its ionic form, whereas the analyte is desorbed in its neutral form if the analytes are ionic over the entire pH range, desorption occurs by using a solution of appropriate ionic strength [92],... 

Electrodialysis Electrical potential Selective ion transport Charged species (ions) Symmetrical ionic Water desalination, fractionation... 

The element whose hydroxide is shown above is indicated noncommittally as E and may have bonds other than the ones shown. If the E—O bond is very nearly covalent, the O—H bond in the hydroxide is broken, (a) if the E—0 bond is ionic, water tends to attack E, displacing the OH ion, and forming the hydrated ion (represented as H20—E+), (b). 

These severe requirements are met principally by ionic, water-soluble polypeptides in which there is little solvent change over the helix-coil transition and in which X = Xn. Poly-L-glutamic acid and poly-n-lysine, which... 

Morais PC, da Silva SW, Soler MAG, Sousa MH, Tourinho FA (1999) Raman study of ionic water-based copper and zinc ferrite magnetic fluids. J Magn Magn Mater 201 105-109... 

Since these bisulfite addition compounds are ionic water-soluble compounds and can be formed in up to 90% yield, they serve as a useful means of separating aldehydes and methyl ketones from mixtures of organic compounds. At high sodium bisulfite concentrations these adducts crystallize and can be isolated by filtration. The aldehyde or ketone can be regenerated by adding either a strong acid or base ... 

An aromatic compound can be W ater soluble If several polar or ionic (water-soluble) groups are bonded to its aromatic ring. The structure of vitamin is based on an aromatic ring, but the ring contains aldehyde, phosphate, hydroxyl, and amine groups. Consequently, vitamin is water soluble... 

Rosati G, Leto di Priolo S, Tirone P. Serious or fatal complications after inadvertent administration of ionic water-soluble contrast media in myelography. Eur J Radiol 1992 15(2) 95-100. 

Yadav RK, Sharma A, Mishra DS, Airon RK, Kalra M, Dua S. An evaluation of myelography with non-ionic water soluble contrast medium—iohexol. J Indian Med Assoc 1999 97(1) 16-19. 

Phospholipids can form organized structures, as shown in Figure 1.12, when suspended in water solutions. The small circles represent the ionic water-soluble ends of the phospholipid molecules, containing phosphate and amino groups. The... 

Fu, X.A. and Qutubuddin. S., Synthesis of titania-coated silica nanoparticles using ono-ionic water-in-oil. Colloids Sutf. A. 178. 151. 2001. 

O-terf-Butyldimethylsilyl groups on the side chains in triarylbismuthines are deprotected by tetrabutylammonium fluoride or p-toluenesulfonic acid to yield non-ionic water-soluble triarylbismuthines bearing neutral hydroxyl groups [98JCS(P1)2511]. 

K.-Ch. Ullman, Stabilisation of TiC>2 dispersions with non-ionic water-soluble molecules. Thesis, University of Stuttgart, 1989. 

Water-soluble polymers, such as polyethylene oxide), can be attached covalently to, e.g., phosphine ligands, to render them water-soluble. Most often this concept has been applied to biphasic catalysis as an alternative to the introduction of ionic water-soluble moieties, such as the sulfonate groups of the archetypical trisulfonat-ed triphenylphosphine (TPPTS cf. Section 3.2.1). 

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