Multi conditions which promote

Conditions which promote multi-domainic goethites are high ionic strength (either [KOH] or salt) and also low synthesis temperature (<40°C). In alkaline solutions, multi-domainic character decreases and domain width increases as Al substitution increases to Al/(Fe-i-Al) of 0.15, whereas at Al/( Al-nFe) >0.15 single domain crystals result (Schulze Schwertmaim, 1984 Mann et al., 1985). Multidomainic goethites can recrystallize to single domain crystals as a result of hydrothermal treatment at 125-180 °C (Fig. 4.9) (Schwertmann et al., 1985). 

The tautomerism of dialkyl phosphonate permits new synthetic protocols in dehalogenation and/or C-P bond formation. The multi-component system consisting of a catalyst, a co-reductant, and an additive promoter cooperates with each other to achieve the catalytic reactions through efficient one-electron reduction, hi this system, the active catalyst is smoothly regenerated by redox interaction with the co-reductant. The selection of the co-reductant is important from this point of view. Furthermore, the oxidized form of the co-reductant should not interfere with, but assist the reduction reaction or at least, be tolerant under the conditions. Additive promoters, which are considered to contribute to the redox cycle, possibly facilitate the electron transfer and/or liberate the catalyst from the reaction adduct. 

Cytokinins play a central role in the regulation of fruit set in many multi-fruited species. Because of their primary site of synthesis in the roots, this provides a mechanism for the plant to maintain fruit load consistent with the plant s ability to produce viable seed based on such important soil conditions as fertility and water availability. The complete mechanism by which cytokinins induce development of fertilized ovaries is unknown, but carbohydrate metabolism in the ovary is one process involved. The cytokinins have the ability to promote carbohydrate metabolism and associated sink strength of the ovary by enhancing the level of the regulator F-2,6-bP. How cytokinins cause modulation of F-2,6-bP levels, and what other metabolic or molecular processes are involved are further questions to be answered. In a general sense, cytokinins act as metabolic stimulants of fertilized ovaries which have become quiescent, and, as such, induce their full development into mature seed-bearing fruit. 

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