Plastic columns

This paper describes application of mathematical modeling to three specific problems warpage of layered composite panels, stress relaxation during a post-forming cooling, and buckling of a plastic column. Information provided here is focused on identification of basic physical mechanisms and their incorporation into the models. Mathematical details and systematic analysis of these models can be found in references to the paper. 

Figure 2. Scheme of the experiment used for the study of the creep induced buckling of a plastic column. (Reprinted with permission from ref. 13. Copyright 1988 Soc. of Plastic Engineers.)... 

Figure 4-1. Components of a simple liquid chromatography apparatus. R Reservoir of mobile phase liquid, delivered either by gravity or using a pump. C Glass or plastic column containing stationary phase. F Fraction collector for collecting portions, called fractions, of the eluant liquid in separate test tubes.

Fill a 10-mL plastic column with about 1 mL protein A-Sepharose, and equilibrate column with 50 mL PBS. 

FIGURE 5-51. Effect of mobile phase polarity on retention of phthalate plasticizers. Column juPorasil (silica, 10 p,m), 3.9 mm ID x 30 cm flow rate 2 mL/min detector UV at 254 nm. Mobile Phase (a) is 5% ethyl acetate in isooctane, (b) is 5% butyl acetate in isooctane. 

A fiber-plastic column, 1 foot in diameter, filled with 12 feet of Calgon Corporation s CPG activated carbon was used to prepare hydrocarbon-free AlCls for a test. This column was used simply because it was available and a much larger diameter column with less height would be designed for a commercial unit. A relatively fast flowrate of 1 gal/min was used in the adsorption column. 

The instrument can work on a variety of column sizes, as well as glass- or plastic-column barrels. The instrument can be programmed with or without a personal computer (PC). The PC adds the capability of saving methods and allows one the control of the cartridge flow rates. The general features of the Spe-ed Wiz are shown in Table 10.1. 

SPE column sizes Syringe-barrel columns Individual flow rates Sample load volumes Elution container Max. elution fractions Glass or plastic columns Dry column with gas Multicolumn SPE Positive pressure or vacuum... 

Why are plastic columns and support frits preferred over glass columns for gel filtration ... 

Figure 1. In vitro test for platelet retention, using plastic columns, packed with fine glass beads whose surfaces are thereafter coated with test polymer (ambient temperature = 37°C).

In the continuous Pu removal experiments small 10 X 100 mm glass columns were packed with PP bioadsorbent (cell loading 0.3 g cells/g plastic column load 1.5 g blo-adsorbent). This column removed 75-80% of 1.7 nCl/100 ml PuCli4 activity at a 15 ml/hour flow rate in a 12 hour operation. Since the maximal Pu removal capacity of this blo-adsorbent was estimated as about 600 nCl/g cells, such a column can be operated at the 1-5 nCi/100 ml level of activity theoretically for at least a month before exhaustion. For practical reasons, due to decreasing viability caused by the toxicity of other heavy metals, not Pu, present, columns should be replaced every week or two for optimal operation. 

Disposable plastic columns with stopcocks (BioRad)... 

Package unit including column, packing, storage tanks, pumps, controls, high pressure, stainless steel. PM cost = 750000 at 450 L column volume with n = 0.14 for volumes < 450 L and n = 0.38 for 450-4500 L column volume. For low pressure, plastic columns and peripherals = X 0.5. 

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