Storage of dissolved

Kattner, G. 1999. Storage of dissolved inorganic nutrients in seawater Poisoning with mercuric chloride. Mar. Chem. 67 61-66. 

Neither of these two preservatives can be recommended here. With the exception of silicate (see Section 2.2.3.2), adding sulphuric acid may be even worse than no treatment. This is particularly true for the preservation of nitrogen compounds. At low pH, nitrite can be lost rather rapidly as a result of its oxidation to nitrate or because of its reaction with ammonia or a-amino acids. The unsuitability of this preservative for the storage of dissolved phosphate has already been outlined in Section 2.2.3.2. 

In the 1950 s, crude oils were either corrosive (sour), or non-corrosive (sweet). Crudes containing more than 6 ppm of dissolved H2S were classed as sour because, beyond this limit, corrosion was observed on the walls of storage tanks by formation of scales of pyrophoric iron sulfides. 

The treatment units used for color removal are the same as those used for turbidity removal. However, the pH must be increased prior to filtration so that the metal hydroxides are removed by the filters. At low pH values, metal ions or their soluble complexes readily pass through the filters and form insoluble species in storage tanks and in the distribution system. For iron salts, it is important that the pH be greater than 6 as the oxidation of iron(II) to iron(III) occurs rapidly above this pH in the presence of dissolved oxygen or other strong oxidants (18). 

The slope of the water solubiUty curves for fuels is about the same, and is constant over the 20—40°C temperature range. Each decrease of 1°C decreases water solubiUty about 3 ppm. The sensitivity of dissolved water to fuel temperature change is important. For example, the temperature of fuel generally drops as it is pumped iato an airport underground hydrant system because subsurface temperatures are about 10 °C lower than typical storage temperatures. This difference produces free water droplets, but these are removed by pumping fuel through a filter-coalescer and hydrophobic barrier before deUvery iato aircraft. 

For the storage of a substance dissolved in a volatile solvent, the solution must be placed directly in the flask, not within a vial. During the evacuation, gently sway the flask and adjust the evacuation speed to avoid sample loss due to a sudden boiling of the solution. Replace the inside space of the flask completely with the solvent vapor (typically methanol) by boiling the sample solution for a period of 1-2 minutes before closing the stopcock. In using this method, however,... 

Since SIAB is water-insoluble, it must be dissolved first in organic solvent prior to addition to an aqueous reaction medium. The most commonly used solvents for this purpose include DMSO and DMF. Typically, a concentrated stock solution is prepared in one of these solvents and an aliquot added to the protein conjugation solution. Long-term storage of the reagent in these solvents is not recommended, however, due to slow uptake of water and breakdown of the NHS ester end. 

Preservation and Storage of Samples for the Determination of Dissolved Organic Carbon... 

Moderate (attenuation and limitation of effects) Use vacuum to reduce boiling point Reduce process temperatures and pressures Refrigerate storage vessels Dissolve hazardous material in safe solvent Operate at conditions where reactor runaway is not possible Place control rooms away from operations Separate pump rooms from other rooms Acoustically insulate noisy lines and equipment Barricade control rooms and tanks... 

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