Cobalt-Uranyl Acetate

Cobalt-Uranyl Acetate TS Dissolve, with warming, 40 g of uranyl acetate [U02(C2H302)2-2H20] in a mixture of 30 g of glacial acetic acid and sufficient water to make 500 mL. Similarly, prepare a solution containing 200 g of cobaltous acetate [Co HsC A O] in a mixture of 30 g of glacial acetic acid and sufficient water to make 500 mL. Mix the two solutions while still warm, and cool to 20°. Maintain the temperature at 20° for about 2 h to separate the excess salts from solution, and then filter through a dry filter. 

The combination of spermine and uranyl acetate, on the other hand, yields well-defined toroids of electron microscopic dimensions. Usually one finds only a few percent of such compacted DNA molecules within a large population of linear or circular DNA strands, but under carefully controlled conditions quantitative compaction to toroids of quite uniform size has been achieved (Fig. 8.6.21) (Bottcher, 1998). Chromium and cobalt ammonium complexes have similar effects, but compaction yields are usually low. The least poisonous system to compact DNA toroids consists of a hydrophobic tripeptide, namely a (yai derivative with a terminal naphthalene sulfonate headgroup (Vengerov et al., 1985). 

Fig. 139. Alveolar macrophage with a tubular invagination from a 220 g female white rat (No. 1 breeder Winkehnann, Borchen-Kirchborchen) which inhaled 10 mg of a powdered cobalt-nickel alloy/m , used in the production of hard metal by Deutsche Edels-tahlwerke in Krefeld, 4 h per day, 5 times per week from October 2-28, 1967 for a total of 19 days. Fbced on October 30, 1967 under methitural anaesthesia by intratracheal instillation of 2.5 % glutaraldehyde in phosphate buffer (pH 7.4) before opening the thorax. Postfixation with 1 % osmium tetrox-ide in phosphate buffer (pH 7.4). Contrasted en bloc for 12 h with 0.5 % uranyl acetate in 70 % ethanol. Embedded in a 2 8 mixture of methyl and butyl methacrylate. Sectioned at 50 nm. Lead citrate after Reynolds (1963). Plate 16/01...

Beta-Propiolactone Benzene Hexachloride Potassium Dichromate Decahydronaphtlialene Cobalt Sulfate Butadiene. Inhibited Glyoxal, 40%Solution Glyoxal, 40% Solution Dowthemi Uranyl Acetate Diethylenetriamine T riethylenetetramine... 

C8H16CI6CU3O4, Copper(II) chloride - 1,4-dioxan (3 2), 43B, 1353 C8H16Cl804Ti2, Titanium(IV) chloride-ethyl acetate complex, 31B, 442 C8H16N2O10U, Uranyl nitrate - bis(tetrahydrofuran), 43B, 1283 CbHi8CI2C0N2O2 f Dichlorobis(N,N-dimethylacetamide)cobalt(II), 39B, 765... 

P-Nltroso-g-naphthol precipitates uranyl Ion from slightly addle solution. Iron, cobalt, nickel, copper, zinc, and molybdate Ions also are precipitated by the reagent. Aluminum, chromium, cadmium, and uranium (XV) give no visible reactions. The precipitation of uranium (Vl) Is most nearly complete In an acetate buffered solution. 

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