High-activity products

The process for the thermal activation of other carbonaceous materials is modified according to the precursor. For example, the production of activated carbon from coconut shell does not require the stages involving briquetting, oxidation, and devolatilization. To obtain a high activity product, however, it is important that the coconut shell is charred slowly prior to activation of the char. In some processes, the precursor or product is acid-washed to obtain a final product with a low ash content (23,25). 

If amylases are to be used as tools for the detailed study of the breakdown and structure of their substrates it is obviously important to separate them from other enzymes and from other naturally associated constituents which may influence the results. It is then equally important to study the properties of the purified amylase and to supply it with the chemical environment necessary to protect it from inactivation and to enable it to act efficiently. With beta amylases this ideal has often been approached. Beta amylases from several sources have been prepared by selective inactivation of other enzymes that accompany them in nature23 and highly active products have been obtained by extensive purification.20 24-26 Balls and his associates have recently reported the crystallization of beta amylase from sweet potato.27... 

Amgoune A, Thomas CM, Ilinca S, Roisnel T, Carpentier J-F (2006) Highly active, productive, and syndiospeciflc yttrium initiators for the polymerization of racemic (3-butyrolactone. Ang Chem Int Ed 45 2782-2784... 

High active products can reach a gel-like viscosity, but can be thinned with Isopropanol or Butyl Propylsolv. 

Hydrogen, however, may also react with other impurities such as dissolved oxygen, sulphur, carbon, etc. and form high activity products. Therefore, the effect of hydrogen on the mechanical properties of a crystal is ambiguous. A discussion of fracture at metal/oxide boundaries has been given recently by [F. Ernst (1995)]. 

Each method has its merits and drawbacks. For example, separation technologies remove some of the high-activity products from the streams and convert them into low-activity streams that are easier to stabilize, but generate separated components with high activity that also require stabilization. This two-phase approach adds to the total cost and may turn out to be very expensive. 

Material flows can be classified as order and replenishment flows. For replenishment the relevant flows are from receiving to pallet reserve, carton pick, and item pick areas from pallet reserve to carton pick area from carton pick to item pick area. The other flows, for customer orders, are relatively more frequent. Consider the flow of a typical high-activity product, which is received in pallets and stored in the pallet reserve area (e.g., the upper levels of pallet rack). It is then moved to the carton pick area (e.g., the lower levels of pallet rack). Individual cartons are removed from the carton pick area and placed in the item pick area (e.g., a gravity flow rack holding cartons). The order pickers selectively retrieve items from the flow racks and place them on conveyors, which carry the items to the sorting area. There the items of each order are sorted into totes, which are then sent to the consolidation area and then to shipping. Some customers may order this product in carton quantities, which may be retrieved directly from the carton pick area. If an order requests a quantity equivalent to 4.2 cartons, then 4 cartons may be retrieved from the carton pick area and the remaining... 

As the alcohol ethoxy-sulphate acid is unstable, the product has to be stored and transported in the neutralised form. The "lauryl" ethoxy-sulphates are commercially available in concentrated forms - 60% AM with ethyl alcohol and 70% AM without any addition. The 70% high-active product is a fluid, pumpable material which is made without using viscosity modifiers such as ethanol. 

Amgoune A, Thomas CM, Roisnel T, Carpentier JF. 2006. Ring-Opening Polymerization of Lactide with Group 3 Metal Complexes Supported by Dianionic Alkoxy-Amino-Bisphenolate Ligands Combining High Activity, Productivity, and Selectivity. Chem Eur J 12 169-179. 

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