Disposal centrifuges

Incubate partially solubilized inclusion bodies at 4°C with constant agitation for 60 min then combine the solutions in one 175-mL disposable centrifuge tube. Adjust the volume to 30 mL with sonication buffer and sonicate for 60 s at maximum output power (see Notes 4,5). 

For sample elution, 2 mL of 0.1 % triethylamine in methanol is added to each cartridge and allowed to pass through the cartridge into 5 mL disposable centrifuge tubes under low vacuum. 

Transfer the homogenate to a chilled 1.5 ml disposable centrifuge tube and centrifuge at 1 000 g for one min at 4°C in order to pellet the nuclei and cellular debris. 

Quickly thaw ES cells (one-half of a confluent 25-cm flask or approx 5 x 10 cells) in a 37°C water bath, and transfer them to a disposable centrifuge tube containing lOmL of prewarmed medium. 

Trypsinize three 175-cm flasks using 5mL trypsin/flask as described above. Add 8mL of medium to each flask, and combine cells in a 50-mL disposable centrifuge tube. Spin for 5min at 260g, and resuspend in 20mL of PBS. 

By contrast, HLW from LWR fuel reprocessing is stored ia cooled, well-agitated, stainless steel tanks as an acidic nitrate solution having relatively few sohds. Modem PUREX flow sheets minimise the addition of extraneous salts, and as a result the HLW is essentially a fission-product nitrate solution. Dissolver soHds are centrifuged from the feed stream and are stored separately. Thus the HLW has a low risk of compromising tank integrity and has a favorable composition for solidification and disposal (11). 

After thickening, a variety of sludge handling and disposal options are available. For example, the thickened sludge can be applied directly to land. If liquid disposal is not applicable to a specific project, the thickened sludge can be dewatered by centrifugation, vacuum filtration, or filter pressing. The dewatered residue can then be land fill or incinerated. These options are discussed further on. 

Centrifugation is performed in a closed system and is therefore an excellent choice for treating volatile fluids. The liquid and solid are mechanically separated by centrifugal force. The removal of most of the liquid increases the solid concentration in, and reduces the volume of, the waste stream. The collected solid waste may then be treated and disposed of or recovered. Three types of units are available for centrifugation the solid bowl, the disk, and the basket. The first two are used in large plants, the third in smaller plants. 

During cheese making, the coagulated milk or curd is used to make cheese while the supernatant whey is a waste product rich in salts, proteins, and lactose. Whey concentration and desalting by UF produce a retentate product that can be used as an animal feed supplement or food additive. The MMV process (Maubois et al., French Patent 2,052,121) involves concentrating the milk by UF after centrifugation to remove the cream and before coagulation to improve yields and reduce disposal costs. 

Centrifuging the screw-cap vial can easily break emulsions, which often form during extraction. The vial will survive up to 6000 g if rubber stoppers are inserted into the centrifuge cup to provide a flat base for the vials. The required phase (usually the top layer) can be easily removed with a pipet or, if it is to be discarded, it can be removed using a disposable pipet connected by tubing to a suction flask and vacuum line. 

Initially, this method utilized 5-mL conical centrifuge tubes as the collection device for final elution of the extract from the Cig tubes. In practice, these tubes were found to be very difficult to clean and in few instances were the cause of cross-contamination when low-concentration samples were extracted following samples with very high concentrations. Since no commercial graduated tubes were available, disposable culture tubes are used as the receiver. These tubes are individually calibrated before use. A solvent blank sample may be processed through the method from extraction to quantification to determine if contamination from glassware occurs. 

Electronic analytical balance Volumetric flasks 100- to 1000-mL Volumetric glass pipets, various sizes Pasteur pipets, 5.75- and 9-in lengths Refrigerated centrifuge Nalgene centrifuge bottle, 250-mL Disposable syringes, 5-cm ... 

Centrifuge tubes Becton-Dickinson BlueMax polypropylene, 15-mL SPE column adapters for 1-, 3- and 6-mL Bond Elut columns SPE plastic reservoirs 75-mL Disposable flow control valve liners for SPE... 

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