Septum swelling

Container integrity can be a problem with certain samples. The Teflon surface of the septum on the 40-mL VOA vial serves as a barrier between hydrocarbons and the soft silicone rubber of the septum. Just a few punctures of this barrier by a syringe needle may allow the vapor to swell the septum. Both light crude oil and condensate samples can swell a septum to a point where it splits and releases material. These problems of container integrity and the volatility of both the matrix and the analyte make it a challenge to find a suitable Statistical Quality Control (SQC) sample for this test. 

A septum develops sub—apically across each progametangium to delimit the terminal multinucleate gametangia from the suspensor cells. The contact wall dissolves, allowing plasmogamy. The developing zygospore swells and forms a thick black warty wall. 

Swell and wash with DCM as described in Protocol 1. Add sufficient DCM to cover resin and flush vessel with nitrogen. Seal with a septum. 

FIGURE 3. A transmission electron micrograph of a section of an alveolar septum of lung tissue of a rat pup exposed to nicotine via the placenta and mother s milk. Swelling of the endothelial cell (asterisks) of the blood-air barrier occurs. Note the focal degeneration of the endothelial cell cytoplasm (star). The blood-air barrier is composed of the endothelial cell (asterisks), type I cell (double arrowheads), and the basement membrane between these cells. Swollen mitochondria can be seen in the interstitial cells (arrowheads). Collagen fibers also occur (arrows), cap = capillary. 

Equivalent weights for PFSI ionomers immediately following precipitation from the reaction medium and for membranes formed as described in section 22.5 were measured by acid-base titration. In brief, the procedure is as follows. A known amount of dried polymer (in a typical measurement, approximately 0.0670 g of polymer) and 0.10 g of NaCl were dissolved in 30 mL of deionized water, and the resulting solution was refluxed in a 150-mL conical-shaped flask at 80°C overnight with constant stirring. The flask was covered with a latex balloon and then filled with nitrogen gas through a septum. The polymer swelled up in water. A few drops of phenolphthalein were added to the solution, which was then titrated with a 0.0100 M... 

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