Ethanolic acid

Hydroxyl Alcohol Ethanol Acids, amines, aldehydes, alcohols... 

Ethanol/acid fixative Add 50 mL glacial acetic acid to 950 mL ethanol. 

Add approx five times the volume of the appropriate fixative (see Chapter 8) to the sample in a small wide-mouth vial and incubate for 4-24 h depending on the optimum for the fixative selected (formalin, 6-12 h Bouin s, 4 h ethanol/acid, 24 h) (see Note 3). 

Although lithium aluminum hydride and boranes are very useful reagents, they are expensive and impractical to employ on a large scale. Other methods of reduction then may be necessary. Of these, the most important are reduction of esters with sodium and ethanol (acids do not react readily),... 

Description of foodstuffs Water Simulants to be used 3 % acetic 15 % ethanol acid Olive oil... 

CM-Sephadex (G-50) in 0.1 M potassium acetate, pH 6.0—Perform the ethanol, acid, and 1.0 M potassium acetate, pH 6.0 washings of CM-Sephadex (G-50) as described above. After the second wash, resuspend the filter cake in 4 volumes of 0.1 M potassium acetate, pH 6.0 (i.e., 1 part... 

Diethyl L-tartrate was usually purchased from Aldrich Chemical Co., Ltd., the diester was also prepared from L-tartaric acid by the procedure of Kocienski2 (triethyl orthoformate-ethanol-acetyl chloride) or Seebach3 [ethanol-acidic ion-exchange resin (Lewatit 3333)]. 

Whilst treatment of the cyclopropene 267 with aqueous acid gives succinate 269, reaction with ethanolic acid gives the a,) -unsaturated ester 270. This divergent reactivity reflects subtle behaviour of the protonated intermediate 268. Whereas the... 

The performic acid is prepared in the usual manner by allowing a mixture of 1.0 ml of 30% (w/v) H2O2 and 9.0 ml of 88% (w/v) formic acid to stand at room temperature for 1 hr, after which it is cooled to 0°C. A known amount of protein, usually the amount used for routine hydrolysates, is dissolved in 1 to 2 ml of the reagent in a cooled hydrolysis tube. If the protein does not dissolve readily in the cold reagent, it can usually be dissolved first in 0.1 ml of 100% formic acid at room temperature. The mixture is kept at 0°C for 4 hr after which performic acid is destroyed by the addition of 0.15 ml of cold 48 % (w/v) HBr per ml of performic acid reagent used. The bromine which forms, as well as the formic acid solution, can best be removed from the hydrolysis tube by rotary evaporation under high vacuum (mechanical pump) at 40°C with NaOH pellets in the condenser trap the condenser should be cooled with dry ice in ethanol. Acid hydrolysis of the oxidized sample and analysis of the resulting hydrolysates are performed in the usual manner ( 2.1.2). 

Johnson D.W., Salmon G.A., Pulse Radiolysis of Methanol and Ethanol Acid-Base Behaviour of Hydroxymethyl and Hydroxyethyl Radicals, J. Chem. Soc, Faraday Trans., 1,1975,71,583-591. 

E2S.10 The key difference between two reactions is that HI would hydrolyse MeCOOMe and produce Mel and MeCOOH (instead of water). The reaction of the ethanolic acid with the acetyl iodide (produced at the end of the catalytic cycle) leads to ethanoic anhydride. See the catalytic cycle in Figure 25.13. 

Fig. 7.8 Overlaid chromatograms fortrimipramine maleinate obtained on a CHI RALPAK AD-H CSP in presence of ethanesulfonic acid and trifluoroacetic acid as acidic additives. Column CHIRALCEL AD-RH (250 x 4.6 mm i.d.) mobile phase n-hexane/ethanol/acidic modifier (85/15/0.1 v/v/v) flow rate 1.0 mt min temp. 25 °C, detection UV 210 nm. (Reprinted with permission from [125]).

Fio. 3. Absorption spectra of chromophores from 125 /jg of authentic hydroxyproline and protein hydrolysate of 1 ml of plasma. Chromophores were concentrated by adding 0.6 ml of water to the final ethanol-sulfuric acid-toluene-Ehrlich s reagent mixture of the colorimetric procedure, shaking the mixture, and separating the water-ethanol-acid phase the latter was then diluted to 3.0 ml with ethanol (L9). 

For touch preps, the slide should be immersed in acetone as soon as possible, but the cells need a moment to adhere to the plane of the glass. Slowly dip the slide into the acetone as a violent action at this point could wash off some of the cells. As is the case with frozen sections, fixation is a matter of choice. In this instance the use of acetone is preferred because the cells are still whole and the membranes require disruption in order for the contents to be accessible for later analysis. However, an ethanol/acid fixative (95% ethanol, 5% glacial acetic acid) is perfectly acceptable if desired. For the other cytology specimens, experimentation within individual systems is necessary. There is no right or wrong way to make these preparations. There is a fine balance struck between the... 

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