Solution chemistry, effect

PZN-PT, and YBa2Cug02 g. For the preparation of PZT thin films, the most frequently used precursors have been lead acetate and 2irconium and titanium alkoxides, especially the propoxides. Short-chain alcohols, such as methanol and propanol, have been used most often as solvents, although there have been several successful investigations of the preparation of PZT films from the methoxyethanol solvent system. The use of acetic acid as a solvent and chemical modifier has also been reported. Whereas PZT thin films with exceUent ferroelectric properties have been prepared by sol-gel deposition, there has been relatively Httle effort directed toward understanding solution chemistry effects on thin-film properties. 

Numerous investigators have attempted to control the precursor structure and related solution chemistry effects with varying degrees of success, to influence subsequent processing behavior, such as crystallization tempera-ture.40-42,78,109 110 Particular attention has been given to precursor characteristics such as structural similarity to the desired product and the chemical homogeneity of the precursor species. For multicomponent films, this latter factor is believed to influence the interdiffusional distances associated with the formation of complex crystal structures, such as perovskite compounds. Synthetic approaches have been geared toward the preparation of multimetal species with cation stoichiometry identical to that of the desired crystalline phase.40 42 83 84... 

Schwartz, R. W. Assink, R. A. Headley, T. J. 1992. Solution chemistry effects in PZT thin film processing spectroscopic and microstructural characterization. In Ferroelectric Thin Films II, edited by Kingon, A. I. Myers, E. R. Tuttle, B. Mat. Res. Soc. Symp. Proc. 243 245-254. 

This review of the various mechanisms points to the possible existence of a combination of surface composition and local solution chemistry effects. 

This interface is critically important in many applications, as well as in biological systems. For example, the movement of pollutants tln-ough the enviromnent involves a series of chemical reactions of aqueous groundwater solutions with mineral surfaces. Although the liquid-solid interface has been studied for many years, it is only recently that the tools have been developed for interrogating this interface at the atomic level. This interface is particularly complex, as the interactions of ions dissolved in solution with a surface are affected not only by the surface structure, but also by the solution chemistry and by the effects of the electrical double layer [31]. It has been found, for example, that some surface reconstructions present in UHV persist under solution, while others do not. 

First Carbonation. The process stream OH is raised to 3.0 with carbon dioxide. Juice is recycled either internally or in a separate vessel to provide seed for calcium carbonate growth. Retention time is 15—20 min at 80—85°C. OH of the juice purification process streams is more descriptive than pH for two reasons first, all of the important solution chemistry depends on reactions of the hydroxyl ion rather than of the hydrogen ion and second, the nature of the C0 2 U20-Ca " equiUbria results in a OH which is independent of the temperature of the solution. AH of the temperature effects on the dissociation constant of water are reflected by the pH. 

M = Al, Ga, In, Tl). The solution chemistry of Al in particular has been extensively investigated because of its industrial importance in water treatment plants, its use in many toiletry formulations, its possible implication in both Altzheimer s disease and the deleterious effects of acid rain, and the ubiquity of Al cooking utensils.For example, hydrated aluminium sulphate (10-30 gm ) can be added to turbid water supplies at pH 6.5-7.5 to flocculate the colloids, some 3 million tonnes per annum being used worldwide for this application alone. Likewise kilotonne amounts of A1(OH)2.5C1o.5 in concentrated (6m) aqueous solution are used in the manufacture of deodorants and antiperspirants. 

The gifted chemists who worked on the "Manhattan Project" recognized and attempted to quantitatively describe the effects of a self-radiolysis soon after the preparation of macroscopic quantities of 239Pu. The present symposium provides an appropriate time and place to cite a number of these individuals for their contributions to an important aspect of Pu solution chemistry. 

Wildung RE, YA Gorby, KM Krupka, NJ Hess, SW LI, AE Plymale, JP McKinley, JK Fredrickson (2000) Effect of electron donor and solution chemistry on products of dissimilatory reduction of technetium by Shewanella putrefaciens. Appl Environ Microbiol 66 2451-2460. 

Casini, A., Cinellu, M.A., Minghetti, G., Gabbiani, C., Coronnello, M., Mini, E. and Messori, L. (2006) Structural and solution chemistry, antiproliferative effects, and DNA and protein binding properties of a series of dinudear gold(l II) compounds with bipyridyl ligands. Journal of Medicinal Chemistry, 49, 5524. 

Sadana U.S., Takkar P.N. Effect of sodality and zinc on soil solution chemistry of manganese under submergerged conditions. J Agr Sci 1988 111 51-55. 

The molecular details by which NAMI-A exerts antimetastatic effects in vivo have not been definitely determined, and may occur by multiple mechanisms. The solution chemistry of NAMI-A involves both loss of Cl and DMSO. Interestingly, the antimetastatic activity is retained under a wide variety of experimental conditions producing solvolyzed intermediates.192 The exact nature of the active species may be difficult to resolve. 

Pitzer, K. S., 1975, Thermodynamics of electrolytes, V, effects of higher order electrostatic terms. Journal of Solution Chemistry 4, 249-265. 

Shape selectivity and orbital confinement effects are direct results of the physical dimensions of the available space in microscopic vessels and are independent of the chemical composition of nano-vessels. However, the chemical composition in many cases cannot be ignored because in contrast to traditional solution chemistry where reactions occur primarily in a dynamic solvent cage, the majority of reactions in nano-vessels occur in close proximity to a rigid surface of the container (vessel) and can be influenced by the chemical and physical properties of the vessel walls. Consequently, we begin this review with a brief examination of both the shape (structure) and chemical compositions of a unique set of nano-vessels, the zeolites, and then we will move on to examine how the outcome of photochemical reactions can be influenced and controlled in these nanospace environments. 

This chapter has discussed the transition metal-catalyzed synthesis of allenes. Because allenes have attracted considerable attention as useful synthons for synthetic organic chemistry, effective synthetic methods for their preparation are desirable. Some recent reports have demonstrated the potential usefulness of optically active axially chiral allenes as chiral synthons however, methods for supplying the enantiomerically enriched allenes are still limited. Apparently, transition metal-catalyzed reactions can provide solutions to these problems. From the economics point of view, the enantioselective synthesis of axially chiral allenes from achiral precursors using catalytic amounts of chiral transition metal catalysts is especially attractive. Considering these facts, further novel metal-catalyzed reactions for the preparation of allenes will certainly be developed in the future. 

One of the objectives of this paper will be to show some specific examples of these effects in electrolysis and illustrate the substantial need for a better understanding of the thermodynamics of the solution chemistry involved in electrodics. Some of these needs are more obvious and have been indicated previously ( 3) and include such items as AG°, Kg0 and Cp data on the systems of interest. However, much more extensive information is necessary on adsorption phenomena, complex ion formation and the equilibrium concentrations of these influential species. This need has always existed but it is even more important now if the current challenges being imposed by energy and materials shortages and environmental control are to be met. 

Ranee, G.A. and A.N. Khlobystov, Nanoparticle-nanotube electrostatic interactions in solution the effect of pH and ionic strength. Physical Chemistry Chemical Physics, 2010. 12(36) p. 10775-10780. 

Abstract Two systems are discussed in this chapter, which are copper activating zinc-iron system with and without depressants. Firstly, the system in the absence of depressants is discussed. And it is obtained that at a specific pH the activation for each mineral occurs in a certain range. Through the electrochemical methods and surface analysis the entity contributing to the activation can be identified which are usually copper sulphides and vary for different minerals. Secondly, the system with depressants is researched. And also the effects of pulp potential on the activation are discussed. The same conclusion can be obtained as the one from the former system. Furthermore, zeta potential are involved in the discussion of activation and die mechanism can be explained firom the changes of zeta potential. Similarly, the activation mechanism of this system is also studied through solution chemistry, bonding of activator with mineral surfaces and surface analysis. 

The effect of solution chemistry on the speciation of the organic contaminant 1-naphtol (1-hydroxynaphthalene) and its complexatiom with humic acid is reported by Karthikeyan and Chorover (2000). The complexation of 1-naphtol with humic acid (HA) was studied during seven days of contact, as a function of pH (4 to 11), ionic strength (0.001 and 0.1 M LiCl), and dissolved concentration (DO of 0 and 8 mg L ) using fluorescence, UV absorbance, and equilibrium dialysis techniques. In a LiCl solution, even in the absence of HA, oxidative transformation of 1-naphtol mediated by was observed. In addition, the presence of humic acid in solution, in the absence of DO, was found to promote 1-naphtol oxidation. These reactions are affected by the solution chemistry (pH, ionic strength, and cation composition). 

Fig. 16.20 Fluorescence quenching (FQ) of 1-naphthol in the presence of HA as a function of pH and reaction time (1-naphthol = 8pmol LHA = 11 ppm C ionic strength of O.IM LiQ) F and F denote fluorescence intensities in the absence and in the presence of the quencher (HA), respectively. Reprinted with permission from Karthikeyan KG, Chorover J (2000) Effects of solution chemistry on the oxidative transformation of 1-naphtol and its complexation with humic acid. Environ Sci Technol 34 2939-2946. Copyright 2000 American Chemical Society...

---