Mixing and Storing

During storage of a suspension, demixing of water and fibers and other components may occur at low and medium consistencies. This has to be avoided. Stirring only a small part of the suspension at regular intervals at different positions in the storing chest is sufficient to hinder or correct separation and reflocculation. Thus the energy demand is limited. 

Vertically suspended stirrer shafts with pairs of propeller blades at several levels of the shaft are used to prevent demixing. In larger diameter storing chests the shaft rotates epicyclically. The kind of equipment in Fig. 4.55 is applied at smaller and medium storage volumes. The energy demand is about 0.02 to 0.1 kW m .  

For large storage volumes towers are used with reduced diameters at the bottom. Only this lower part is agitated by a mixing propeller. In this case stock can also be stored at higher consistencies, even above 10%. 

In storing high consistency stock of about 10 to 15%, the crucial requirement is the continuous removal of the stock. For that the stock is diluted close to the outlet. Here demixing is usually not a problem. 

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Proteinase K (Eluka) or Pepsin (Boehringer Mannheim Biochemicals, Indianapolis, IN) for stock solution 10 mg Proteinase K, 10 mL IX DEPC-treated PBS mix and store 1-mL aliquots in RNase-free Eppendorf tubes at -20°C. 

Forty-two laboratories were identified for inspection. Ongoing and completed studies would be examined as available. The inspections used a checkhst that was divided into two parts, one part covering laboratory operations and the other study conduct. The checklist arbitrarily placed mixing and storing of test substances in the area of laboratory operations and distribution and characterization of the substances in study conduct. 

Galactose-1-phosphate substrate mix 2 ml galactose-1-phosphate (see 1. above) and 1 ml 14C-galactose-l-phosphate (see 2. above). Mix and store at -20°C. UDP-glucose, 21.6 mM UDP-glucose disodium salt (FW variable calculate the concentration for each batch). Dissolve in H20. 

It was not until the nineteenth century that artists began to purchase ready-made commercial paints. Today paint colors have standardized specifications. Regardless of type, paint still consists of pigment and binder, as it has for centuries. Many colors originally produced from natural pigments are now made synthetically. The metal paint tube was developed in 1841. Paints that for centuries had been mixed and stored by the artist in various ways in the studio were suddenly available in an easily portable container. Artists who had found it difficult to paint on location were able to create many masterpieces outdoors, on location, as a result of tube paint becoming available. 

The polyol, the chain extender, and any catalysts are mixed and stored as a separate item. The second item, the diisocyanate prepolymer, is kept as a "B" part until the material is ready for use. When the two parts are mixed, the chain extension and cross-linking take place simultaneously. Methylene diisocyanate and a catalyst such as an organic tin or bismuth salt provide the... 

TDM spray solution was prepared as follows Solution A 2.5 g of 4,4 -tetramethyldiami nodi phenyl methane (TDM) was dissolved in 10 ni. of glacial acetic acid and diluted with 50 nL of H2O. Solution B 5 g of potassium iodide was dissolved in 100 nt of H20. Solution C 0.3 g of ninhydrin was dissolved in 90 mL of H20 diluted with 10 nt of glacial acetic acid. Solutions A and B and 1.5 nt of solution C were mixed and stored in a brown bottle. 

The ingredients are, by weight, 7 parts potassium perchlorate and 5 parts aluminum powder. Both should be as fine as possible. After weighing they are thoroughly mixed and stored in a sealed container until needed. 

Magnesia mixture (reagent for phosphates and arsenates). Dissolve 55 g of magnesium chloride and 105 g of ammonium chloride in water, barely acidify with hydrochloric acid, and dilute to 1 L. The ammonium hydroxide may be omitted until just previous to use. The reagent, if completely mixed and stored for any period of time, becomes turbid. 

Sufficient packages are taken, and their contents are mixed, either with a spatula or by mechanical stirring, preferably at 20-30 C. Similar-sized portions are removed from all the packages with a scoop or cup (packages up to 1 kg or 11) or with a probe appropriate to the viscosity (packages over 1 kg or 11) and combined to give a total of about 11, which is then mixed and stored in an airtight container. 

S-Labeled compounds. Ethyl mercaptan- ss and ethylene oxide added to AICI3 in a Dry Ice-acetone bath, mixed, and stored 24 hrs. at room temp, in a stoppered flask 2-ethylthioethanol-35S. Y 75% based on mercaptan. K. Groves and R. Haguwitz, J. Agr. Food Ghem. 9, 262 (1961). 

Translation mix (7.62x) 1 mM ATP, 63 pM GTP, 26 pg/ml creatine phosphate (Sigma, 10 mg/ml in 10 mM K-HEPES, pH 7.4), 20 mM K-HEPES, 20 mM calf liver tRNA, 13 pM amino acid mix, 263 pM spermidine (in 10 mM K-HEPES, Sigma), and 250 pi distilled water. For analyzing the products of in vitro translation of poliovirus RNA in HeLa cell-free extract, the amino acid mix used for the translation mix is not supplemented with methionine. For production of poliovirus in HeLa cell-free extract, the amino acid mix is supplemented with methionine. Aliquot mix and store at -80°C. Individual components should be stored at -20°C. 

Mixing and Storing To generate a uniform blend of suspension components, and to prevent suspension components from de-mixing. 

Figure 13 Colloidal method for treating powders to fractionate, mix and store.

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