Column charge

The checkers used a 30-mm. (I.D.) chromatographic column charged with approximately 250 g. of activated (400° for 12 hours), acid-washed, chromatographic aluminum oxide (Merck and Co., Inc.). 

Ammonia-free water may be prepared in a conductivity-water still, or by means of a column charged with a mixed cation and anion exchange resin (e.g. Permutit Bio-Deminrolit or Amberiite MB-1), or as follows. Redistil 500 mL of distilled water in a Pyrex apparatus from a solution containing 1 g potassium permanganate and lg anhydrous sodium carbonate reject the first 100 mL portion of the distillate and then collect about 300 mL. 

Figure 6.8 Silica (a) and zirconium (b) column charge states.

Figure 8 Calculated HOMO (first and third column) and LUMO (second and fourth column) charge density for Si (,IF140-double (top panel), SiioH O-bridge (bottom panel) for the ground (first and second column) and excited (third and fourth column) states the structures shown are the relaxed ones.

Elution of a chitin column, charged with wheat-germ extract, with 0.01 M acetic acid (as opposed to 0.05 M hydrochloric acid)133 gave protein(s) mitogenic for purified, human peripheral-lymphocytes.508 This discovery is contrary to several past reports (see, for example, Ref. 156) that showed that WGA had no mitogenic activity. The relationship between WGA and the newly described protein(s), termed wheat-germ mitogen, has yet to be established. 

Cation exchange columns charged with silver ions can be used in a similar way (Adlof and Emken, 1981). 

Another application of MIC is the purification of monoclonal antibodies from mouse ascites fluid by HPLC on an IDA column charged with Zn, as illustrated in Fig. 11 [80]. Calmodulin, a calcium-binding protein, could be effectively purified on a Eu -TED column only with a mobile phase containing... 

Proline-Catalyzed Cyclization of Triketone 107 to Give the Wieland-Miescher Ketone (109) [28]. Crude oily trione 107 (ca. 2 mol) in DMSO (2 L) tvas treated tvith (S)-proline (11.5 g, 0.1 mol, 5 mol%) and the resulting mixture tvas stirred under argon at 18 °C for 5 days. The solvent tvas removed at 70 °C (0.1 torr) and the resulting dark green oil (420 g) tvas adsorbed on a column charged tvith silica (3 kg) Elution tvith 17% ethyl acetate in hexanes afforded 276 g product vhich vas further purified by distillation (b.p. 108-112 °C/0.25 torr, bath temp. 150 °C) to give the enantiomerically enriched ketone 109 (255 g, 1.43 mol, 72%) in 70% ee ([ajp = +70°). 

It consists of 4 reactors (volume 500 ml x 4), 4 absorption columns charged with soda lime, an absorption column to remove carbon dioxide... 

After n-pentane effluent has essentially drained from the column, charge a 50 to 50 volume mixture of toluene-acetone. Collect the effluent in a 500-mL separatory funnel. Collect 250 mL of the toluene-acetone (plus n-pentane) effluent or until the effluent is practically colorless (only in exceptional cases will more than 300 mL of effluent be required). 

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