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Soluble fraction

Both of the alkaloids anhalamine (62) from l ophophora williamsii and lophocerine (63) from l ophocereus schotti were isolated (after the properties of purified mescaline had been noted) in the search for materials of similar behavior. Interestingly, lophocerine, isolated as its methyl ether, after dia2omethane treatment of the alkaU-soluble fraction of total plant extract, is racemic. It is not known if the alkaloid in the plant is also racemic or if the isolation procedure causes racemization. [Pg.541]

Suspension- and emulsion-polymerized PVDF exhibit dissimilar behavior in solutions. The suspension resin type is readily soluble in many solvents even in good solvents, solutions of the emulsion resin type contain fractions of microgel, which contain more head-to-head chain defects than the soluble fraction of the resin (116). Concentrated solutions (15 wt %) and melt rheology of various PVDF types also display different behavior (132). The Mark-Houwink relation (rj = KM°-) for PVDF in A/-methylpyrrohdinone (NMP) containing 0.1 molar LiBr at 85°C, for the suspension (115) and emulsion... [Pg.387]

Because of the zwitterion formation, mutual buffering action, and the presence of strongly acid components, soybean phosphoHpids have an overall pH of about 6.6 and react as slightly acidic in dispersions-in-water or in solutions-in-solvents. Further acidification brings soybean phosphoHpids to an overall isoelectric point of about pH 3.5. The alcohol-soluble fraction tends to favor oil-in-water emulsions and the alcohol-insoluble phosphoHpids tend to promote water-in-oil emulsions. [Pg.99]

To produce highly purified phosphatidylcholine there are two industrial processes batch and continuous. In the batch process for producing phosphatidylcholine fractions with 70—96% PC (Pig. 4) (14,15) deoiled lecithin is blended at 30°C with 30 wt % ethanol, 90 vol %, eventually in the presence of a solubiHzer (for example, mono-, di-, or triglycerides). The ethanol-insoluble fraction is separated and dried. The ethanol-soluble fraction is mixed with aluminum oxide 1 1 and stirred for approximately one hour. After separation, the phosphatidylcholine fraction is concentrated, dried, and packed. [Pg.101]

Pig. 4. Batch process for producing phosphatidylcholine fractions. 1, Ethanol storage tank 2, deoiled lecithin 3, solubiHzer 4, blender 5, film-type evaporator 6, ethanol-insoluble fraction 7, ethanol-soluble fraction 8, aluminum oxide 9, mixer 10, decanter 11, dryer 12, aluminum oxide removal 13, phosphatidylcholine solution 14, circulating evaporator 15, cooler 16, dryer and 17, phosphatidylcholine. [Pg.101]

In the continuous process for producing phosphatidylcholine fractions with 70—96% PC at a capacity of 600 t/yr (Pig. 5) (16), lecithin is continuously extracted with ethanol at 80°C. After separation the ethanol-insoluble fraction is separated. The ethanol-soluble fraction mns into a chromatography column and is eluted with ethanol at 100°C. The phosphatidylcholine solution is concentrated and dried. The pure phosphatidylcholine is separated as dry sticky material. This material can be granulated (17). [Pg.101]

Component Cmde Deoiled Alcohol-soluble fraction Alcohol-ins oluble fraction PC 70 PC 90 ... [Pg.102]

Historical. Pyridines were first isolated by destructive distillation of animal bones in the mid-nineteenth century (2). A more plentifiil source was found in coal tar, the condensate from coking ovens, which served the steel industry. Coal tar contains roughly 0.01% pyridine bases by weight. Although present in minute quantities, any basic organics can be easily extracted as an acid-soluble fraction in water and separated from the acid-insoluble tar. The acidic, aqueous phase can then be neutrali2ed with base to Hberate the pyridines, and distilled into separate compounds. Only a small percentage of worldwide production of pyridine bases can be accounted for by isolation from coal tar. Almost all pyridine bases are made by synthesis. [Pg.332]

The analogous reaction with ammonia leads ultimately to sihcon nitride. In the past, hydrocarbon soluble fractions of the ammonolysis were iacorrecdy referred to as sihcon diimide. This improper designation occasionally persists as of the mid-1990s. [Pg.31]

Fraction I cold water-soluble nitrogen (CWSN) Fraction II cold water-insoluble nitrogen (CWIN), which is hot water-soluble Fraction III hot water-insoluble nitrogen (HWIN). [Pg.131]

The detergent method for insoluble fiber superseded the cmde fiber method and became the method of choice for insoluble fiber analysis until the 1980s, when methods were developed to recover soluble fiber as well. Some analysts still prefer the NDF procedure for insoluble fiber. The method is simple, inexpensive, reproducible, and amenable to routine assays. The disadvantage is the inabiUty to recover the soluble fraction. See Reference 14 for more information on detergent methods. [Pg.71]

Leaching is the removal of a soluble fraction, in the form of a solution, from an insoluble, permeable sohd phase with which it is associated. The separation usually involves selective dissolution, with or without diffusion, but in the extreme case of simple washing it consists merely of the displacement (with some mixing) of one interstitial liquid by another with which it is miscible. The soluble constituent may be solid or liquid and it may be incorporated within, chemically combined with, adsorbed upon, or held mechanically in the pore structure of the insoluble material. The insoluble sohd may be massive and porous more often it is particulate, and the particles may be openly porous, cellular with selectively permeable cell walls, or surface-activated. [Pg.1673]

Mechanism The mechanism of leaching may involve simple physical solution or dissolution made possible by chemical reaction. The rate of transport of solvent into the mass to be leached, or of soluble fraction into the solvent, or of extract solution out of the insoluble material, or some combination of these rates may be significant. A membranous resistance may be involved. A chemical-reaction rate may also affec t the rate of leaching. [Pg.1673]

The lac resin is associated with two lac dyes, lac wax and an odiferous substance, and these materials may be present to a variable extent in shellac. The resin itself appears to be a polycondensate of aldehydic and hydroxy acids either as lactides or inter-esters. The resin constituents can be placed into two groups, an ether-soluble fraction (25% of the total) with an acid value of 100 and molecular weight of about 550, and an insoluble fraction with an acid value of 55 and a molecular weight of about 2000. [Pg.868]

Washing of samples to determine water soluble fraction or for ashing to determine organic content... [Pg.354]

The influence of the gel content in polyisoprene-tackifier blends on creep resistance and peel behaviour have been recently studied [62]. The gel content was achieved by cross-linking the adhesives with electron beam irradiation. The molecular weight of the soluble fraction in the blend was always dominated by that of the initial elastomer. Creep resistance was achieved either through molecular weight increases or gel content increases. However, the peel strength is strongly... [Pg.648]

There was obtained a mixture of N-(2 -diethylamino-2 -methylethyl)phenthiazine and N-(2 -diethylamino-1 -methylethyDphenthiazine in the form of a viscous yellow oil, BP 202° to 205°C/2 mm. This oil was treated in ethereal solution with ethereal hydrogen chloride and gave a white solid which was fractionally crystallized from ethylene dichloride. The less soluble fraction, N-(2 -diethylamino-2 -methylethyl)phenthiazine hydrochloride formed colorless rhombs, MP 223° to 225°C. The more soluble N-(2 -diethylamino-1 -methylethyl)-phenthiazine hydrochloride was obtained as colorless prismatic needles, MP 166° to 168°C. [Pg.593]

Cell lysates from mutant strains of X. campestris were incubated with radiolabelled UDP[14C] glucose or GDP[,4C] mannose, the other sugar nudeotide substrates being unlabelled. The reaction mixture was then divided into lipid and soluble fractions. Where would you expect the radiolabel to be found and what produd, if any, would you expert from strains with defidendes in the following genes ... [Pg.221]

Soluble tetrameric form (G4) Composed of four identical monomers and stabilized by hydrophobic interactions of hydrophobic amino acids at the C terminus of monomers. Abundant for brain AChE and BChE in mammalian body fluids and in the soluble fraction of tissue homogenates. [Pg.359]

Following the same procedures described in the above-mentioned study, additional extractive data were obtained for the epoxy phenolic enamel that was irradiated at 4.7-7.1 Mrad at 25 and — 30 °C in the presence of distilled water, 3% acetic acid, and n-heptane. The changes in the amount of extractives resulting from the irradiation treatment are shown in Table IX. In the case of the water and acetic acid extractives, there was no change in either the chloroform-soluble fractions or the chloroform-insoluble fractions. In the case of the n-heptane extractives, the amount of extractives decreased when the irradiation temperature was reduced from +25 to — 30°C. Infrared spectra of the chloroform-soluble residues from the water and acetic acid extractives of the unirradiated and irradiated enamel were identical to the chloroform-soluble residues from the solvent blanks. In other words, the epoxy phenolic... [Pg.39]

Speciation of plutonium leached from the glass cubes is shown in Figure 1. The first bar represents the total amount of insoluble plutonium and is the summation of suspended plutonium (the difference between the values for filtered and unfiltered waters) and sorbed plutonium—viz., the amount removed from the cubes by a 0.1 M perchloric acid wash, normalized to the volumes of leachant solutions so that it is comparable to the other values in the graphs. For simplicity, the insoluble fractions are combined in one bar, whereas the various oxidation states in the soluble fraction are represented by separate bars. It should be noted that the ordinate scale varies among the graphs. [Pg.337]

The reported molar masses of polyesters obtained by enzymatic catalysis are relatively low, generally below 8000, except for polymers recovered by precipitation.336 This procedure results in the elimination of a soluble fraction consisting of low-molar-mass linear and cyclic oligomers.336 An Mw as high as 46,400 has thus been reported for a poly(tetramethylene decanedioate) obtained... [Pg.83]

A detailed study of the radiochemical reactions of phenylarsenic compounds has been published by Grossmann. Once again unable to effect isolation of all compounds, he was able, however, to get evidently reliable values for the sums of all compounds with one, two and three phenyl-arsenic bonds, respectively, as well as ionic arsenic and a further organic-soluble fraction which appeared to be a group of polymeric phenylarsenic compounds. Selected data from this work are given in Table 6. [Pg.72]

Also interesting is the solid-state interaction between the water-extract-able fraction and the acetone-soluble fraction. Heating of the irradiated ferrocene at 110° C causes a sharp decrease in the water-extractable activity (from 55 to 15% in 2-3 hours). This 40% does not appear as ferrocene and is assumed to form some stable molecular species other than ferrocene. [Pg.223]

The spore coats make up a major portion of the spore, consisting mainly of protein with smaller amounts of complex carbohydrates and Bpid and possibly large amounts of phosphorus. The outer spore coat contains the alkali-resistant protein fraction and is associated with the presence of disulphide-rich bonds. The alkali-soluble fraction is... [Pg.270]

Clearly, the control of gene expression at the transcriptional level is a key regulatory mechanism controlling carotenogenesis in vivo. However, post-transcriptional regulation of carotenoid biosynthesis enzymes has been found in chromoplasts of the daffodil. The enzymes phytoene synthase (PSY) and phytoene desaturase (PDS) are inactive in the soluble fraction of the plastid, but are active when membrane-bound (Al-Babili et al, 1996 Schledz et al, 1996). The presence of inactive proteins indicates that a post-translational regulation mechanism is present and is linked to the redox state of the membrane-bound electron acceptors. In addition, substrate specificity of the P- and e-lycopene cyclases may control the proportions of the p, P and P, e carotenoids in plants (Cunningham et al, 1996). [Pg.266]


See other pages where Soluble fraction is mentioned: [Pg.262]    [Pg.277]    [Pg.380]    [Pg.99]    [Pg.466]    [Pg.339]    [Pg.366]    [Pg.214]    [Pg.335]    [Pg.71]    [Pg.424]    [Pg.426]    [Pg.708]    [Pg.317]    [Pg.583]    [Pg.442]    [Pg.350]    [Pg.367]    [Pg.466]    [Pg.32]    [Pg.296]    [Pg.165]    [Pg.340]    [Pg.170]   
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See also in sourсe #XX -- [ Pg.79 ]

See also in sourсe #XX -- [ Pg.42 , Pg.45 ]




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