Air float technique

Figure 4.4 The equipment used in the integrating rising air float technique.

Sargent, D.M. (1982a) The rising air float technique for the measurement of stream discharge. Advances in Hydrometry (proceedings of the Exeter Symposium, July 1982). lAHS Publ. no. 134. 

Sargent, D.M. (1982b) The accuracy of streamflow measurement using the rising air float technique. Proc. Inst. Civ. Engrs. 73 (part 2), 179-82. 

To size the two species however, it is necessary to separate them. A sink-float technique has been developed to separate the two. A carbon tetrachloride - tetrabromoethane mixture having an SG about 2.5 was used. The dry crystal mixture is added to the dense organic liquid, then put under vacuum to remove entrapped air bubbles. The suspension is then centrifuged for several hours to separate out the gypsum which floats and the hemihydrate which sinks. Tests on synthetic mixtures showed that a very clean separation is possible. 

The Magic Carpet system (AstroTurf Industries) (13) is a novel installation technique in which turf and adherent underpad are unwound from a core and floated onto the subbase of a playing field by air pressure suppHed from ducts in the base. To expose the subbase for other sports uses, the turf—pad combination is roUed up and stored at the edge of the field or in a recessed storage compartment. 

The most common application of carbon adsorption in municipal water treatment is in the removal of taste and odor compounds. Figure 12 provides an example of a process flow diagram for a municipal water treatment plant. In this example water is pumped from the river into a flotation unit, which is used for the removal of suspended solids such as algae and particulate matter. Dissolved air is the injected under pressure into the basin. This action creates microbubbles which become attached to the suspended solids, causing them to float. This results in a layer of suspended solids on the surface of the water, which is removed using a mechanical skimming technique. Go back to Chapter 8 if you need to refresh your memory on air flotation systems. 

The most serious possible problem with this measurement technique is the possible loss of OH prior to detection. The primary diagnostic indicator for the presence of contamination is the temperature of the sample air flow after passage through the detection volume. If boundary-layer air has intruded into the detection volume, the sample air temperature will rise above ambient because the walls of the detection module are always warmer than the ambient air temperature. For example, at float altitude the temperature difference is —15 °C. 

Carman (C6) described the successful development and application to a uranium resin-in-pulp process of a continuous countercurrent ion-exchange pilot plant. This new technique is based on the observation that the resins at the correct level of air agitation float in close proximity to the surface of the pulp. So long as the resin beads are able to move about gently but freely in the surface layer, a satisfactory rate of ion exchange is possible. Under this condition, the mechanical damage to the resin due to attrition is negligible. 

Langmuir-BIodgett-Kuhn (LBK) films are prepared by a dipping process in which monolayers floating at the air/water interface are deposited on a solid substrate. LBK films are highly ordered supramolecular assemblies. By selection of the amphiphilic molecules and adjustment of the transfer conditions, the LBK technique offers extensive structural control and opens a wav to optimize matrices for photoactive dyes. 

The most difficult part of psilocybin mushroom cultivation is the observance of the rules of pure culture technique. These are the sanitary code of mushroom cultivation. There are usually many varieties of bacteria and fungal spores in our environment floating in the air, clinging to our hands and clothing, issuing from our mouths with every exhalation. Extreme measures must therefore be taken to keep these out of our mycelial cultures, which they would rapidly overrun. The following points should be diligently observed. Work in a clean, uncluttered, dust free room. Immediately before work wash the work table and spray the room with disinfectants. Scrub arms, hands, and nails with disinfectant soap. 

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