Other Fractions

The lysosomes of L cells contain considerable amounts of bound sialic acid, despite the presence of neuraminidase in these organelles. The high level might be expected because lysosomal membrane is derived in part from the plasma membrane (de Duve and Wattiaux, 1966). The phospholipids and cholesterol contents of lysosomes and plasma membrane of rat liver are similar. (Thines-Sempoux, 1967). Histochemical studies of Rambourg (1969) indicate that the lysosomes are rich in carbohydrate. It has also been shown that radioactive d- 

The soluble fractions of cells, i.e., the supernatant solution remaining after centrifugation at high speeds, appear to be very poor in sialic acid (Table I). Essentially all cellular glycoproteins and gangliosides appear to be bound to particulate matter, i.e., membranes. 

Atterfelt, P., Blohme, L, Norrby, A., and Svennerholm, L., 1958, Sialic acids of hog gastric mucosa, Acta Chem. Scand. 12 359-360. 

Barton, N. W., and Rosenberg, A., 1973, Action of Vibrio cholerae neuraminidase (sialidase) upon the surface of intact cells and their isolated sialolipid components, J. Biol. Chem. 248 7353-7358. 

Bennett, H. S., 1963, Morphological aspects of extracellular polysaccharides, J. Histo-chem. Cytochem. 11 15. 

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Other fractions available are b.p. 60-80 , 80-100 . and 100-120 when the boiling point exceeds 120 , it is usually called ligroiiL. ... 

Fractional distillation. Fig. II, 60, 2 illustrates a set-up for fractional distillation wdth a Hempel-type column and cold finger, the latter to give manual control of the reflux ratio. Any other fractionating colunm, e.g., an all-glass Dufton or a Widmer column may, of course, be used. 

Use the molecular weights given to evaluate the factor 1 - p/p2 for each of the systems then use these factors to evaluate M for the other fractions. Compare the molecular weights obtained in the two solvents. 

The maximum rates of crystallisation of the more common crystalline copolymers occur at 80—120°C. In many cases, these copolymers have broad composition distributions containing both fractions of high VDC content that crystallise rapidly and other fractions that do not crystallise at all. Poly(vinyhdene chloride) probably crystallises at a maximum rate at 140—150°C, but the process is difficult to foUow because of severe polymer degradation. The copolymers may remain amorphous for a considerable period of time if quenched to room temperature. The induction time before the onset of crystallisation depends on both the type and amount of comonomer PVDC crystallises within minutes at 25°C. 

However, for the past 30 years fractional separation has been the basis for most asphalt composition analysis (Fig. 10). The separation methods that have been used divide asphalt into operationally defined fractions. Four types of asphalt separation procedures are now in use ( /) chemical precipitation in which / -pentane separation of asphaltenes is foUowed by chemical precipitation of other fractions with sulfuric acid of increasing concentration (ASTM D2006) (2) solvent fractionation separation of an "asphaltene" fraction by the use of 1-butanol foUowed by dissolution of the 1-butanol solubles in... 

Product to heat exchanger along with other Fractionator O.H. Prod. —5 ... 

Other fractional lives could similarly be defined. For example, the life-time t is the time required for the concentration to decay to lie its initial value then we find T = l/k. The lifetime is the average time elapsed before a molecule reacts. In pharmaceutics, a shelf-life tgo is defined to be the time required for Ca to reach the value 0.90 Ca, giving tgo = O.lOSlkf)... 

Gas chromatographic analysis at 120° on a 2.2-m. column packed with 10% diethylene glycol succinate showed the forerun fraction to contain approximately 50% product. The other fraction is pure 2,3-epoxycyclohexanone. 

Addition of other fractions IPN4-IPN14 to the culture medium resulted in activation of root development in BTCL explants to different extent (Table 1). 

When a microporous material, e.g. a zeolite, is used as a catalyst, only those molecules whose diameters are small enough to enter or pass through the pores can react and leave the catalyst. This is the basis for so-called shape-selectivity (Fig. 3.40). Reactant selectivity is encountered when a fraction of the feed molecules can enter the zeolite, whereas the other fraction cannot. For the molecules produced in the interior the same reasoning applies. The favoured products are the less bulky ones, i.e. those with diameters smaller than the pores of the zeolites. For instance, in the zeolite represented in Fig. 3.40 the production of p-xylene is favoured over the production of o- and m-xylenes. Also the bulkiness of the transition state can lead to a different. selectivity, as shown in the last example in Fig 3.40. 

So far we have considered only the recoil-free fraction of photons emitted by the source. The other fraction (1 —/s), emitted with energy loss due to recoil, cannot be resonantly absorbed and contributes only as a nonresonant background to the transmitted radiation, which is attenuated by mass absorption in the absorber... 

Thus, the distance /2a may be regarded as a measure of the width of the distribution A k) and is called the half width. The half width may be defined using 1/2 or some other fraction instead of 1/e. The reason for using 1/e is that the value of k at that point is easily obtained without consulting a table of numerical values. These various possible definitions give different numerical values for the half width, but all these values are of the same order of magnitude. Since the value of I (x, r) falls from its maximum value of (2jr) to 1/e of that value when x — v t equals v/lja, the distance flja may be considered the half width of the wave packet. 

The soil equilibrium parameter, Uts, measures the departure from the Mn fractionation in the oxic native soil, which is caused by the saturation and incubation of the soil. This parameter can acquire values equal to or larger than one. Compared to the native state, an increase in the Uts indicates that some fraction(s) have been grossly enriched in Mn. Note the fact that a fraction that has lost some Mn will only reduce its own contribution to the Uts value, but its contribution will not be subtracted from that of the other fraction(s) since the product F, xUtfi can not acquire negative values. 

PP synthesized using TiCl4/Et3Al is mostly isotactic, but two minor fractions are also produced. One is a soluble, atactic PP, whilst the other fraction is a partially crystalline, elastomeric stereoblock of iso- and a-tactic PP sequences.98 Elastomeric PP may also be prepared using the ansa-titanoccnc complex, (26), (although this catalyst does undergo rapid deactivation).99 Stereoblock formation was attributed to an equilibrium mixture of slowly interconverting isospecific and aspecific catalyst sites. Other stereoblock PP materials have been prepared via chain transfer between two catalysts of different stereoselectivities.101,102... 

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