Subject acetone extraction

The acetone extracts were diluted 2 1 with water and partitioned against methylene chloride. The methylene chloride-soluble extracts were analyzed by comparative TLC (X). The aqueous phases were concentrated to dryness and dissolved in water that contained 5% acetonitrile and 0.2> acetic acid. These solutions were applied to SEP-PAK cartridges (Waters Associates) and the cartridges were washed with 5-10 ml of water and eluted with 5 ml of 50t acetonitrile. From 90 to 95% of the 1 C was recovered from the cartridges in the 50% acetonitrile eluate. The eluates were concentrated to dryness and dissolved in 18% acetonitrile/1% acetic acid and subjected to HPLC as previously described for PCNB metabolism in peanut roots (6). 

Cohen and Wheals [334] determined ten hydrolysable carbamate and substituted urea herbicides in soil in amounts down to 0.001-0.05 ppm. In this method, a solution of the herbicide-containing extract of the soil is spotted onto a silica gel G plate and developed with hexane acetone (5 1). The plate is sprayed with 1-fluoro-l,4-dinitrobenzene in acetone and heated to 190 °C to produce the 2,4-dinitrophenyl derivative of the herbicide amine moiety acetone extracts of the areas of interest are subjected to gas chromatography. 

If the above test is positive, the sample may be further subjected to a modified Weber color test for polyisoprenes. For this test, an acetone-extracted polymer (0.05 g) is dissolved or suspended in carbon tetrachloride, treated with a little solution of bromine in carbon tetrachloride and heated in a water bath to remove excess bromine. The residue is then warmed with a little phenol. In the presence of polyisoprenes, the solid or the solution turns violet or purple and gives a purple solution with chloroform. The test is also positive for natural rubber and butyl rubber. 

Pipe fragments may be extracted by sonication with acetone prior to TEA analysis. The concentrated acetone extract may be subjected to TLC as described above. Pipe samples without visible residue may be extracted with methylene chloride and examined by GC-TEA for the detection of NG. These pipe fragments may be re-extracted with acetone and the extract examined by TLC to detect the presence of both NG and NC. This provides good confirmation of smokeless powder as the explosive in the absence of even partial powder grains. Although examination of residues of low explosives by IR spectroscopy has been reported, the results are equivocal and difficult to interpret. 

While enologists have been interested in the odorous constituents of grapes and wines for many years, Hennig and Villforth (1942) and Hennig (1943, 1950-1951) seem to have made the first systematic studies on the subject. They extracted wine with pentane and after hydrolysis identified the alcohols and acids. They reported the following aldehydes, ketones, and related compounds (formaldehyde, acetaldehyde, propion-aldehyde, cinnamaldehyde, vanillin, acetone, methyl ketone, acetyl-methylcarbinol, and acetal—caproaldehyde and higher members of the series, benzaldehyde, and furfural were not positively identified but probably also occur) alcohols (methyl, ethyl, isopropyl, isobutyl, isoamyl, and a-terpineol—n-propyl, n-heptyl, and sec-nonyl (2-nonanol)... 

A wood xylan was prepared from birch fibers that had been subjected to acetone extraction and chlorite delignification. The xylan fraction was extracted with a solution of 6.5% KOH in a nitrogen atmosphere at 20 C for 3.7 hours. The extract was acidified and the xylan was precipitated with ethanol. 

Chemical Assay of Fractions H and L in Urine. Table 2 shows that small amounts of acetone extractable peptides were present in the daily urine specimens of healthy subjects and that 20-30% of this material was in the LM fraction. The total amount of UA was increased in several clinical states but only in pregnancy was the percent of LM fraction more than 35. Diabetic urine was not assayed. 

As the alkaloid was extracted with hexane, acetone, and ethanol, subjected to column chromatography, acidified (AcOH) and then neutralized (NaOH), the cationic form was formulated as a hydroxide salt. However, only two OH groups were detectable on H NMR spectroscopy. Only slight differences were found in the UV spectra taken in methanol [kmax (loge) = 218 (4.68), 302 (4.39), 394 (4.08) nm] and methanol+NaOH [T-max (loge) = 228 (4.66), 310 (4.39) nm]. Three tautomeric forms can be formulated which are shown in Scheme 42. Two of them possess the isoquinolium-7-olate moiety. The H NMR data are presented in Table IV. They indeed unambiguously resemble the cationic species 112. 

The process for the production of the pseudo-ionone referred to in the first claim, consisting in the subjection of a mixture of citral and acetone to the action of an alkaline agent, and in purifying the product of this reaction, extracted by means of ether, by fractional distillation, substantially as described. 

The methods EN 1528 1996 and EN 12393 1998 comprise a range of old multiresidue methods of equal status, which are widely accepted throughout Europe. These are, e.g., the Luke method and the German Deutsche Forschungsgemeinschaft (DFG) methods S8 and S19 ° (all based on extraction with acetone), the Association of Official Analytical Chemists (AOAC) method 970.52 (using acetonitrile extraction and liquid-liquid partition combined with Horisil column cleanup) and the Dutch ethyl acetate extraction combined with GPC. All methods have been subjected to inter-laboratory studies, although not with all pesticide/matrix combinations, which would be impossible to achieve. 

A homogenized sample of cereals, vegetables, fruits or potatoes (10-20 g) is extracted with an organic solvent such as acetone and methanol. After filtration, the extract is concentrated to about 20 mL by rotary evaporation below 40 °C. The residue is transferred with 5% sodium chloride (NaCl) aqueous solution and partitioned twice with n-hexane. The n-hexane extracts are dried with anhydrous sodium sulfate and subjected to a Florisil column chromatographic cleanup procedure. The eluate from the Horisil column is concentrated to dryness and the residue is dissolved in an appropriate amount of acetone for analysis by GC/NPD. ... 

IC-0 residue is cleaned up with a mixture of dichloromethane and acetone by liquid-liquid partitioning under neutral conditions and then extracted into diethyl ether under acidic conditions. The diethyl ether in the extract is removed by rotary evaporation and the residue is dissolved in buffer solution, which is subjected to a cleanup procedure using a Sep-Pak Cig Env. column. 

Isoxathion is extracted from plant materials with aqueous acetone. The extracts are concentrated and partitioned with n-hexane after addition of sodium chloride. The n-hexane phase is collected and concentrated after dehydration. The extract is partitioned with n-hexane and acetonitrile. The acetonitrile phase is collected, concentrated, and subjected to Horisil column chromatography. Isoxathion is eluted with diethyl ether-n-hexane after washing the column with the solvent. Isoxathion in the eluate is concentrated and dissolved in acetone and injected into a gas chromatograph for quantitative determination. 

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