Stabilizing solutes

Gra.des. There are three primary commercial sodium dithionite products 88 min wt % anhydrous product, 70 wt % dry product (often blended with other stabilizers or additives), and 125 g/L stabilized solution. 

Low temperatures can cause a phase separation in stabilized solutions in which case one phase can become deficient in stabilizer and subject to runaway reactions. Acrylic acid can crystallize out of stabilized solution, and subsequent thawing of these essentially pure acrylic acid crystals can initiate runaway reactions, often with severe consequences. Thawing of crystallized (frozen) materials needs to be accomplished using established procedures in thaw boxes or similar devices. If established procedures are not available, a safety review needs to be conducted and a procedure developed prior to thawing the material. 

J. H. Crowe, J. F. Carpenter, L. M. Crowe, and T. J. Anchordoguy, Are freezing and dehydration similar stress vectors A comparison of modes of interaction of stabilizing solutes with biomolecules, Cryobiology, 27, 219 (1990). 

Macromolecular crystals grow in an equilibrium state with their mother liquor. Disrupting this equilibrium can often destroy the crystals or their ability to diffract X-rays. This situation can be exacerbated by the transfer of the crystal to a solution containing a heavy atom. Therefore, it is important, once crystals are removed from their sealed environment, to first transfer them to a stabilizing solution and let them re-equilibrate before further transfer to the heavy atom solution. Usually, a stabilizing solution is identical to the mother liquor in which the crystal was grown, but with a higher concentration of precipitant. 

Determination of Emulsion Stability and Oil Droplet Size. A combination of centrifugation and spectrophotometric techniques was used for the evaluation of emulsion stability. Solutions... 

A stock solution of 3.0% potassium permanganate in 10% nitric acid (prepared fresh daily) was used to stabilize the mercury collected in the rinses from the sampling train. The stabilized solutions were then returned to TraDets Columbus, Ohio laboratory for analysis. 

Figure 3. Apparatus for analyzing the mercury in the permanganate-stabilized solutions...

Both hydrolysis and condensation are reversible. Alcohols will reverse the silane hydrolysis stabilizing solution of silanols for a period of time. Solution stability measured in days or weeks can be achieved. 

Chlorine dioxide is almost never used in a concentrated liquid form, as the liquid is unstable and can explode. It is not stored in any significant quantity, although it is available in a stabilized solution form (typically 3 to 12% CIO2, with carbonate/bicarbonate or other stabilizers). The more concentrated solutions (>5%) require activation with acid, while the more dilute forms (<5%) become self-activating when diluted a further four to five times. 

Instead, for Set A, 18 cm by 18 cm. fabric samples were soaked in the stabilizer solution for 30 minutes and then immediately placed on pin-frames to drain and dry. As shown in Table III, the add-ons obtained by this procedure were much closer to those expected. 

Set B was prepared in substantially the same way, but with minor alterations. Larger samples were used, 15 cm by 91 cm. The samples were loosely folded and allowed to soak in the stabilizer solution for 30 minutes, then rinsed with distilled/deionized water to remove any stabilizer left on the surface. The fabrics were then hung over a glass rod and allowed to air dry. Again, the add-ons were much closer to those desired (Table IV). 

High importance Flowability Absolute and bulk densities Compressibility Polymorphism Solubility Solid-state stability Solution stability... 

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