Aluminum-foil filter

In a 250 ml Erlenmeyer flask covered with aluminum foil, 14.3 g (0.0381 mole) of 17a-acetoxy-3j5-hydroxypregn-5-en-20-one is mixed with 50 ml of tetra-hydrofuran, 7 ml ca. 0.076 mole) of dihydropyran, and 0.15 g of p-toluene-sulfonic acid monohydrate. The mixture is warmed to 40 + 5° where upon the steroid dissolves rapidly. The mixture is kept for 45 min and 1 ml of tetra-methylguanidine is added to neutralize the catalyst. Water (100 ml) is added and the organic solvent is removed using a rotary vacuum evaporator. The solid is taken up in ether, the solution is washed with water and saturated salt solution, dried over sodium sulfate, and then treated with Darco and filtered. Removal of the solvent followed by drying at 0.2 mm for 1 hr affords 18.4 g (theory is 17.5 g) of solid having an odor of dihydropyran. The infrared spectrum contains no hydroxyl bands and the crude material is not further purified. This compound has not been described in the literature. 

Substrate, of aluminum foil, scattering by different thicknesses, 230, 231 of filter, paper in spot test, 230 of Mylar film, excellence, 230, 231... 

Field fortification samples are stored under various conditions in the fleld. Generally, after the weathering period is complete, the fleld fortification samples such as dosimeter sections are wrapped in aluminum foil, placed in a pre-labeled zip-type bag, and immediately placed on dry-ice in a cooler or in a freezer. Field fortification samples such as hand washes or face wipes are prepared in labeled jars, the lids are immediately taped with electrical tape, and the jars are placed in a zip-type bag and wrapped in bubble-pack and immediately placed in frozen storage. Air tubes or air filters are collected after weathering and wrapped so as to prevent breakage. These samples are then placed in a pre-labeled zip-type bag and immediately placed in frozen storage. 

Table I Tendency of Methacrylate Polymers to Become Insoluble Samples on Aluminum Foil, Single-Carbon-Arc Fade-ometer (Corex D Filter), 62°C...

Then the cooled tube is wrapped in aluminum foil except for an area near the bottom of its neck, which is scratched with a glass cutter. The neck is snapped to open the tube, and the solid reaction product is removed and ground in a mortar. The powder is transferred to a 3-L beaker or Erlenmeyer flask and is stirred for 5 h with 1500 mL of deionized water. The mixture is allowed to settle for up to 3 h, then it is filtered through fluted filter paper. The solid residue... 

Cover the output end with two layers of aluminum foil (no plug), and autoclave the filter in a nylon bag. Separate the air vent valve screw from the unit to facilitate the circulation of steam around the filter. 

Place the labeled filters between sheets of filter paper, wrap in aluminum foil, and autoclave for 10 mm. 

Sandwich the filters individually between filter paper, wrap loosely in aluminum foil, and bake at 80°C in vacuo for 2 h. 

The powdered quinones were dispersed homogenously in a dish made of aluminum foil and covered with the appropriate filter. All quinones were irradiated successively under dried nitrogen for 4 h at 20 °C. 

Filter-off the cathode liquid, if desired, and then perform a little experiment Add a few drops of the anode liquid to a small sample of your cathode liquid. Wham What you get is a gelatinous precipitate of ferrous hydroxide hydrate. The cathode liquid will contain sodium hydroxide, commonly called lye. Use this solution to unclog your sink, or simply discard it. If you want, you can play around with it a little. Take some aluminum foil, and drop it into your cathode liquid. Watch as the sodium hydroxide in the cathode liquid consumes the aluminum foil, producing hydrogen gas. 

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