Separation sedimentation

Figure 4. Comparative detection of 4-chlorobiphenyl catabolic gene abundance by blot hybridization of pSSSO plasmid DNA probe to target DNA extracted from sediments. A B spatially separated sediments C control self hybridizations. (Units A B, ug total DNA C ng of probe DNA.)...

Separation or clarification techniques, grit separation, sedimentation, air flotation, filtration, microfiltration and ultrafiltration, and oil-water separation. 

A beverage emulsion is a concentrate added to sugar and carbonated water to make soda and fruit drinks. The oil-in-water emulsion provides flavor as well as opacity in products such as orange soda. Traditionally, gum arabic has been used to stabilize these emulsions. Interfacial starch derivatives (Section 20.4.2) are used to prevent creaming (phase separation), sedimentation, and loss in flavor and opacity, where desired, both in the concentrate and in the finished beverage. The concentrate is made by homogenizing the oils with an equal amount of the solubilized lipophillic starch, citric acid, sodium benzoate and color. A fine emulsion, typically 1 micrometer or less, is required for stability and for opacity, where desired. 

Do the analytical measurements reflect total chemical or separate sediment bound fi om dissolved compon its ... 

Figure 6. Laser grain size analyses of two separate sediment samples from Bone Chamber.

In spite of the droplets being destabilized electrostatically, no evidence of droplet coalescence is seen. By the same token, an electrostatically stabilized emulsion might still coalesce and separate, sediment, or cream if other destabilizing forces overbalance the electrostatic component. Creaming refers to concentration of the dispersed phase without completely separating the oil and water phases. 

At sea, flocculent surface sediments were siphoned off the tops of Soutar box cores and gently sieved, taking care to keep the sediment material at in-situ temperatures. The >75 p,m fraction was kept in bottom water at in-situ temperatures for the duration of each cruise, and returned to the laboratory in Columbia, SC, where stock foraminiferal cultures were maintained in a 7 °C environmental chamber. Separate sediment samples from the top 0.5 cm of cores collected at each site were incubated on board the ship at in-situ temperature with the vital probe CeUTracker Green (Molecular Probes, Invitrogen Detection Technologies) to label foraminifera that were alive at the time of core collection (Bernhard 2000), and these sediments were then preserved for later foraminiferal identification and shell chemistry analyses on shore. 

To obtain the q(r) / Pmm curve from sedimentation curve, c (R, A/=const.), one can plot the relative concentration, c/c0, as a function of particle radius obtained from particle displacement, AR, that occurred over the time, At, using eq. (V.53). If the diffusion rate is negligibly small, the c = c (AR / AO curves match each other at all times, At. The latter allows one to separate sedimentation and diffusion in polydisperse systems as well. To... 

Sayles et al. (1976) have described a device that allows collection of pore water samples under in situ conditions. To achieve this, a tube is pressed about 2 meters deep into the sediment, like a harpoon. Then the pore water is withdrawn from various sections of the tube, through opened valves, and concomitantly passed through filters. The crucial step of separating sediment and pore water thus happens under in situ conditions. The obtained water samples are then ready to be analyzed ex situ. The concentrations which were measured by Sayles et al. (1976), however, do not differ greatly from those which were obtained from the same location by expressing pore water under ex situ conditions. 

The techniques described below have been tested for sediment analysis at the occasion of three interlaboratory studies (TBT-spiked sediment, harbour sediment and coastal sediment). As detailed in Section 5.3, they were first tested with simple solutions to verify that no systematic error could be attributed to the detection step. Since calibration is of paramount importance, participants were provided with pure calibrants of tributyltin chloride synthesized by TNO for the verification of their own calibrants. In all the methods, the storage of the extracts (when necessary) was always at 4 °C in the dark. The moisture correction was carried out by drying a separate sediment portion of 1 g at (105 + 2)°C for 2 h the moisture content obtained by the different laboratories ranged from 1.2 to 2.3%. 

Hvdrocvclones use centrifugal force to separate sediments. A hydrocyclone consists of a cone-shaped vessel into which a slurry is fed tangentially, thereby creating a vortex. Heavier particles settle and exit at the bottom while water and s iments exit through an overflow pipe. Hydrocyclones may be useful where a sharp separation by particle size is needed. 

This is a combination of centrifugal sterilization in bactofuges (65 to 70 °C) and UHT heating of the separated sediment (2-3% of the milk), followed by recombination. Since the total amount of milk is not heated in this process, the taste is improved. The storability is ca. 8-10 days. 

Regardless to which configuration of the chambers is adopted the water can be provided to any of the Sedimentation Tanks. Therefore the Sedimentation Tanks can be consider as a separate Sedimentation Subsystem. 

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