Press fraction

Various techniques have been developed to handle fruit degraded by Bot-rytis cinerea. These include hand selection of deteriorated fruit, followed by whole-cluster pressing and segregation of press fractions, cryoextraction, as well as thermal processing (Ribereau-Gayon et al., 1976). 

Pour the resulting dark reddish-brown liquid into 500 ml. of water to which 17 ml. of saturated sodium bisulphite solution has been added (the latter to remove the excess of bromine). Steam distil the resulting mixture (Fig. II, 41,1) , collect the first portion of the distillate, which contains a little unchanged nitrobenzene, separately. Collect about 4 litres of distillate. Filter the yellow crystalline solid at the pump, and press well to remove the adhering liquid. The resulting crude m-bromonitrobenzene, m.p. 51-52°, weighs 110 g. If required pure, distil under reduced pressure (Fig. II, 19, 1) and collect the fraction of b.p. 117-118°/9 mm. it then melts at 56° and the recovery is about 85 per cent. 

The Vepex process developed in Hungary (Table 9) involves disintegration of plant materials followed by double screw pressing to maximize juice production. Green chloroplastic protein is removed by direct steam-injection heat treatment at 82°C with the addition of flocculents and centrifugation. The white protein fraction is separated from the chlorophyU-free process juice by direct steam injection at 80°C, followed by centrifugation and drying (94). 

J. M. Curling, ed.. Methods ofP/asma Protein Fractionation, Academic Press, Inc., New York, 1980. 

Web Heat-Set Publication and Commercial Inks. Almost all heat-set inks are now printed on web offset presses, and are based on vehicles containing synthetic resins and/or some natural resins. These are dissolved in hydrocarbon solvent fractions which are specially fractionated for use in the ink industry. They vary in boiling range between 180 and 300 °C. Small percentages of alkyd resins (qv) may be contained in these inks. They dry in less than one second by means of solvent evaporation in a heatset oven. These ovens utilize high velocity hot air to raise the web temperature to 120-150 °C. 

Et20, wash with 10% aqueous Na2C03, H2O, dry (Na2S04), evaporate and fractionate under reduced press using a short Vigreux column. It decomposes when boiled at atm press. [J Am Chem Soc 74 547 7952 84 2550 7962.]... 

Isobutyl chloroformate [543-27-1] M 136.6, b 123-127 /atm, 128.8 /atm, d 1.053, n 1.4070. It can be dried over CaCl2 and fractionated at atm press while keeping moisture out. Its purity can be checked by conversion to the phenyl urethane derivative with PhNCO [Saunders et al. J Am Chem Soc 73 3796 7957.] IR v 1780cm [Thompson and Jameson Spectrochim Acta 13 236 7959 Rose Justus Liebigs Ann Chem 205 227 1880]. 

In addition to the above, purification of /V-methylacetamide can be achieved by fractional freezing, including zone melting, repeated many times, or by chemical treatment with vacuum distn under reduced pressures. For details of zone melting techniques, see Knecht in Recommended Methods for Purification of Solvents and Tests for Impurities, Coetzee Ed. Pergamon Press 1982. 

The propionamide can be dried over CaO. H2O and unreacted propionic acid were removed as their xylene azeotropes. It was vacuum dried. Material used as an electrolyte solvent (specific conductance less than 10 ohm cm" ) was obtained by fractional distn under reduced pressure, and stored over BaO or molecular sieves because it readily absorbs moisture from the atmosphere on prolonged storage. [Hoover Pure Appl Chem 37 581 I974 Recommended Methods for Purification of Solvents and Tests for Impurities, Coetzee Ed., Pergamon Press, 1982.]... 

Propargyl chloride (3-chloropropyne) [624-65-7] M 74,5, b 58 /760mm, 65 /760mm, d 1.03, n 1.435. Purified by fractional distn at atm press. Note that a possible impurity propargyl alcohol has b 114-115°/atm. [Henry Chem BerS 398 1 875.] HIGHLY TOXIC and FLAMMABLE. 

Triethyl orthoformate (1,1,1-triethoxymethane) [122-51-0] M 148.2, m 30°, b 60°/30mm, 144-146°, d 0.891, n 1.392. Fractionate first at atm press, then in a vac. If impure, then wash with H2O, dry over anhyd K2CO3, filter and fractionate through a Widmer column. [Sah and MaJ Am Chem Soc 54 2964 1932 Ohme and Schmitz Justus Liebigs Ann Chem 716 207 1968.] IRRITANT and FLAMMABLE. 

Cathepsin D (from bovine spleen) [9025-26-7] Mr 56,000, [EC 3.4.23.5]. Purified on a CM column after ammonium sulfate fractionation and dialysis, then starch-gel electrophoresis and by ullracentrifugal analysis. Finally chromatographed on a DEAE column [Press et al. Biochem J 74 501 I960],... 

Compound Mole Fraction Critical Press. (atm) Critical Temp. ( R) Pseudocritical Press. Pseudocritical Temp. ... 

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