Containers solution fill depth

The important role played by the solution fill depth in determining the sublimation rate has already been touched upon and can hardly be overstated. It depends on the shape of the containing vessel in relation to the fill volume. Ideally, a fill depth of 5 mm is to be recommended. Freeze-drying of chemically labile products at fill depths in excess of 20 mm is to be avoided. Where for pharmacokinetic or other reasons e.g. solubility) a certain volume is prescribed for the administration of the reconstituted solution, the limitation of fill depth has to be achieved by other means. This often involves the use of a vial with a larger-than-ideal diameter. For reasons of cost and suboptimal utilisation of freeze-drier... 

Model Disposal System. The specific disposal systems modeled use lined pits as described by others (1-3). The lining is usually rubber or concrete, and is used to prevent pesticide solution from leaching to the surrounding area. Because of the impervious liner, the only transport route for parent pesticide is volatilization, providing the liner remains intact. The simplicity of these systems allowed the use of a crystallizing dish as a model disposal pit. The dish (50 x 100 mm inside depth, 0.044 m inside diameter, 0.095 m capacity, 310 ml) was filled to the brim with water or soil containing the desired amount of pesticide. 

The dye-sensitised solar cell (DSSC) is constructed as a sandwich of two conducting glass electrodes filled with a redox electrolyte. One of the electrodes is coated, using a colloidal preparation of monodispersed TiOj particles, to a depth of a few microns. The layer is heat treated to rednce resistivity and then soaked in a solution of the dye until a monomolecnlar dispersion of the dye on the TiO is obtained. The dye-coated electrode (photoanode) is then placed next to a connter electrode covered with a conducting oxide layer that has been platinised , in order to catalyse the reduction of the mediator. The gap between the two electrodes is filled with an electrolyte containing the mediator, an iodide/triodide conple in acetonitrile. The structure is shown schematically in Fignre 4.29. 

Round plastic pots of 25 cm diameter and 25cm depth were filled with a mixture of topsoil, peatmoss, vermiculite, and perlite (4 2 1 1 vol/vol). A rooted 10-20 cm Salvia stem cutting (two or three nodes) was placed in each pot. Plants were watered as necessary. They were fertilized weekly with 1.0 1 of a 2 tsp/5 gal solution of a 15-30-15 soluble fertilizer containing trace elements (Stern s Miracle-Gro , with 0.05% each of Cu, Mn, and Zn as the sulfates and 0.1% Fe as a chelate) with 1 ml of an 85% phosphoric acid solution added to counteract basicity. This routine was used for all experiments. 

Measure the conductivity of each solution and also the I.O.N.S. tapwater and distilled water using the apparatus described in the reference material. Your supervisor will show you how to assemble and use it. Be sure to rinse the container and electrodes with distilled water after each measurement so that there is no contamination of any solution. Also be sure to fill the container to the same depth each time. The more electrode surface exposed to the solution, the higher the current. Thus, filling the container to different levels may lead to false conclusions. 

For blind nuclear injections, oocytes are placed into a petri dish containing a 1.0-mm nylon mesh (Small Parts Inc., Miami Lakes, FL, cat. Q-CMN-1000). The mesh can be attached to the bottom of the dish with a few drops of chloroform. The grid wells of the mesh are similar in dimension to the diameter of the oocyte and serve to hold the oocytes in place. The petri dish is filled with MBSH media and the oocytes are oriented under a stereomicroscope with a pair of blunt forceps in the grid wells, with the pigmented animal hemisphere at the top. The injection needle is inserted at the center of the pigmented hemisphere and the needle tip is driven into the oocyte a depth of approximately one-fifth the diameter of the oocyte. The success rate of blind injections depends greatly on practice, but eventually a nuclear hit-rate of 70-90% is obtainable. The best way to practice nuclear injections is to inject oocytes with a 20 mg/ml solution of blue dextram and determine if the blue color is associated with the nuclear or cytoplasmic fractions after oocyte dissections. It should also be noted that RNA can be injected directly into isolated nuclei devoid of cytoplasm (Terns and Dahiberg, 1994). 

A laboratory fixed-bed adsorption column filled with a synthetic sulfonic acid cation-exchange resin in the acid form is to be used to remove Na" ions from an aqueous solution of sodium chloride. The bed depth is 33.5 cm, and the solution to be percolated through the bed contains 0.120 meq Na /cm At saturation, the resin contains 2.02 meq Na /cm resin. The solution will be passed through the bed at a superficial Lnear velocity of 0.31 cm/s. For this resin, Michaels [70] reports that the overall liquid mass-transfer rate 0.86t>2 , where is the superficial liquid velocity, cm/s, and is expressed as meq Na /cm s (meq/cm ). The relative adsorptivity of Na" " with respect to for this resin is a 1,20, and this is constant for the prevailing concentration level. Define the breakpoint concentration as 5% of the initial solution concentration, and assume that practical bed exhaustion occurs when the effluent concentration is 95% of the iniital. Estimate the volume of effluent at the breakpoint, per unit bed cross section. 

If the bunds are sufficiently watertight and stable it may be possible to raise and control the water level within the contained area by adjusting the level of the overflow of the weir boxes. This may affect the settling regime of the fill and in particular of the fines, see also section 6.7.2. It might also be a solution to create sufficient water depth to allow for floating equipment like a spreader pontoon in the reclamation area. 

Rape seeds (Brassica napus L.) were sown in gravel in plastic pots with holes in the bottom. The pots filled with gravel to a height of 12 cm were placed in plastic bins containing nutrient solution to a depth of 5 cm. The nutrient solution was changed every 3 days for 19 days after which the stress program was started. 

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