Vacuum washing procedures

Filter the wet resin and rinse with distilled water. Repeat the washing procedure until the washing water is neutral to pH paper. Rinse with three 100-ml portions of methanol. Evaporate off the remaining methanol in a rotary film evaporator under vacuum, rotating slowly at 40°C, until visibly dry. 

COj that might have been dissolved in water. The out-flow water from each batch was tested conductometrically for completeness of the washing procedure. The washed ACC modules were then dried under vacuum at 120°C, cut to desired dimensions (about 1.0 X 1.5 cm), weighed accurately and kept in a desiccator for further use. 

Add 2 mL of hexadecane and 2 boiling stones to the 500-mL distillation flask containing the combined isooctane extracts, and attach the flask to a suitable vacuum distillation assembly. Evacuate the assembly to about one-third atmosphere, then immerse the flask in a steam bath, and distill the solvent. When isooctane stops dripping into the receiver, turn off the vacuum, wash down the walls of the flask with 5 mL of isooctane added through the top of the distillation head, then replace the thermometer and again evacuate. The isooctane should distill over in about 1 min. At the end of this distillation, add another 5-mL portion of isooctane, and repeat the stripping procedure. 

Carboxymethylcellulose slurry (equivalent of 75 g of dry material)—Slowly wet 75 g of dry resin in distilled water. Draw off the supernatant (after the resin has settled) with vacuum filtration. Resuspend the filtered resin cake in 1.5 L of 0.5 M NaOH (30 g of NaOH dissolved in 1.5 L of distilled water). Allow the resin to settle, draw off the supernatant, and wash the resin cake twice, as before, in 2.5 L volumes of distilled water. Resuspend the resin cake in 2.5 L of 0.5 M HC1 (100 ml of concentrated HC1 in 2.4 L of distilled water). Allow the resin to settle, draw off the supernatant, and wash the resin cake twice, as before, in 2.5 L volumes of distilled water. Repeat the wash procedure described above with 1.5 L volumes of 0.03 M sodium acetate buffer, pH 5.0, until the pH and ionic strength of the drawn-off supernatant is the same as that of the sodium acetate buffer (pH and conductivity meter). Resuspend the resin cake in 1.5 L 0.03 M sodium acetate buffer, pH 5.0. Add 2 g/liter sodium azide for storage to prevent bacterial growth. Remove the azide by washing again in 0.03 M sodium acetate buffer, pH 5.0 when it is ready to be used by the class. 

Collect the solid product using the sintered glass funnel and vacuum filter flask. Rinse the reaction flask with 50 mL of cold ethyl acetate and wash the solid in the filter funnel. Repeat this washing procedure two more times. 

The commercial ACC was washed by the procedure, especially ions, described in our previous works [6,14] to remove impurities remaining in its structure from the activation process. In this procedure, ACC sample was placed in a flow-through washing cup and eluted with 5 L of warm (60°C) conductivity water in a kind of successive batch operations for 2 days with bubbling in order to avoid possible adsorption of CO that might have been dissolved in water. The out-flow water from each batch was tested conductometrically for completeness of the washing procedure. The washed ACC modules were then dried under vacuum at 120°C, cut to desired dimensions (about 1.0 X 1.5 cm), weighed accurately and kept in a desiccator for further use. 

To 100 ml. of a saturated aqueous solution of tetrasodium pyrophosphate at 40° there is added 75 ml. of glacial acetic acid. After the acetic acid has been added, the temperature is brought back up to 40° and the solution agitated until crystallization is complete (approx. 2 to 3 hours). Crystals will appear in 30 to 60 minutes and grow slowly. When crystallization has proceeded for about 30 minutes, the temperature may be dropped slowly to 30°, but not less. The crystals are filtered off using vacuum, washed with two portions of ice water, and dried at 100°. This procedure yields about 6 g. of anhydrous crystals which, if grown slowly enough, are of sufficient size for study under a microscope. 

Anhydrous FeCl3 (7.3 g) was placed in a 500-mL 3-necked flask and heated to 100 °C under N2 and placed under vacuum. This procedure was repeated two more times to remove all moisture and air from the flask and then allowed to cool under N2 pressure. CHCI3 (75 mL) was added to the flask and 0.015 moles of 3-octadecylthiophene was added dropwise and stirred for 2 days at room temperature. The viscous reaction mixture was then precipitated into MeOH, filtered and washed repeatedly with MeOH and H2O. Soxhlet extractions with MeOH and acetone then drying under vacuum at 60 °C yielded a brown polymer (93%). 

In the assay procedure, labeled protein is isolated and separated from small labeled products by filtration. To each tube is added 14 ml of saturated ammonium sulfate solution, the top is replaced, and the tube is inverted. The contents are filtered under suction through a 24-mm glass fiber filter (Whatman GF/A) held in a polypropylene filter holder (Gel-man). The tubes, including the top, are washed twice with 15 ml of 50% saturated ammonium sulfate solution, and the washings are filtered. Each filter is washed three times with about 25 ml of 50% saturated ammonium sulfate solution, twice with 25 ml of ice-cold 1 N HCl, and twice with 15 ml of acetone the vacuum source is turned off while the funnel is being filled at each of these washing steps. The extensive wash procedure is required to obtain low blanks of the order of 500 cpm (0.05 to 0.1% of the total radioactivity in the sample filtered). At the conclusion of the washes, the filter is dry and free of ammonium sulfate and HCl. 

An alternative procedure is to leave the syrupy residue in a vacuum desiccator over anhydrous calcium chloride and siUca gel, and to Alter ofl the successive Crops of crystals as they separate. These are washed with light petroleum, b.p. 40-60°, spread on a porous tile and recrystallised. 

Ether - Starting fluid (works great - Quaaaaack ) 2. Home made mercuric acetate (Now this stuff can be special ordered from ones chem supplier but there s a delay, may look funny - Quaaaaack , and is more expensive. So what is the solution to this Make it yourself Its easy, quantitative, and cheaper. Strike mentions this in the book and points ducks to a reference. Follow the EXACT same procedure for Mercuric Propionate except use glacial acetic acid...quack ). You ll need to use 20 to 25% more of the home brew mercuric acetate since it is a little contaminated with acetic (ducks can t get it totally dry without a vacuum oven). 3. NaOH washed Brazillian is fine Quack No need to purify further for starting material ... 

This is a way to do this procedure without having to use one of those crazy tube furnaces stuffed with thorium oxide or manganous oxide catalyst [21]. The key here is to use an excess of acetic anhydride. Using even more than the amount specified will insure that the reaction proceeds in the right direction and the bad side reaction formation of dibenzylketone will be minimalized (don t ask). 18g piperonylic acid or 13.6g phenylacetic acid, 50mL acetic anhydride and 50mU pyridine are refluxed for 6 hours and the solvent removed by vacuum distillation. The remaining residue is taken up in benzene or ether, washed with 10% NaOH solution (discard the water layer), and vacuum distilled to get 8g P2P (56%). 

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