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P-C-111C <br /> 4.5.5.3 Ammonia or ammonium salts . Using two tall form gas washing bottles, <br /> 250 ml . capacity, each with fritted cylinders (Corning 31760 or 31770 or equal) , <br /> pour 50 ml . of the compound into one bottle and 50 ml . of freshly prepared <br /> saturated aqueous mercurous nitrate solution into the second bottle. Connect <br /> the second bottle to a water aspirator and connect the two bottles in series. <br /> Draw air through the bottles for 5 minutes at a rate that will give continuous <br /> air bubbling but yet permit no spray or foam from the cleaner to enter the <br /> mercurous nitrate solution. A blackening of the frit occurring within 5 minutes <br /> indicates the presence of ammonia or ammonium salts . The use of a silicone <br /> type antifoaming agent in the compound ' ; recommended. <br /> 4.5.6 Glycol ethers. <br /> 4.5.6. 1 Ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, <br /> diethyleneglycol monobutyl ether and diethyleneglycol diethyl ether. <br /> 4.5.6. 1 . 1 Preparation of sample. Place approximately 35 ml . of a strongly <br /> acidic, sulfonated polystyrene type cationic exchange resin, hydrogen form, <br /> medium porosity (Amberlite IR-120 or equal) in a column. Wash with water, then <br /> with absolute ethanol . Pass 5.0 ml . of the compound diluted with 20 ml . <br /> absolute ethanol through the column. Collect the effluent in a 100 ml . volu- <br /> metric flask containing 0.35 g. of ethylene glycol monoethyl ether acetate, <br /> accurately weighed to the fourth decimal . Wash the column with absolute eth- <br /> anol . Continue washing until the flask is filled to the mark. Do not let the <br /> level of the liquid drop below the top of the resin. The resin can be regen- <br /> erated by washing with 3N hydrochloric acid, followed by water until washings <br /> are neutral , and then with absolute ethanol . <br /> 4.5.6. 1 .2 Column preparation. Pack a 6 foot column of 1/4 inch copper <br /> tubing with 20 percent diethylene glycol succinate on 60 to 80 mesh acid- <br /> washed Chromosorb W. Condition the column at 190°C. for 16 hours . <br /> 4.5.6. 1 . 3 Apparatus. The apparatus shall be a gas chromatograph equipped <br /> with a suitable recorder and a flow-control assembly to provide constant mass <br /> flow-rate of helium gas through the detector during programmed temperature <br /> operation, and separate controls for injection port, detector, and column <br /> temperatures. The operating conditions shall be as follows: <br /> Detector cell temperature, °C. 300 <br /> Detector cell current, ma. 150 <br /> Injection port temperature, °C. 250 <br /> Helium flow at exit, ml ./minute 85 <br /> Column heating rate, °C./minute 5.6 <br /> Starting column temperature, °C. 60 <br /> Finishing column temperature, °C. 185 <br /> 12 <br />