Waxy component

Due to a waxy component in the cell wall these organisms are difficult to stain with ordinary stain solutions, the hydrophobic nature of the wall being stain repellent however, if the bacterial smear on the slide is warmed with the stain, the cells are dyed so strongly that they are not decolorized by washing with dilute acid, hence the term acid-fast. Many bacterial spores exhibit the phenomenon of acid fastness. 

Solid hydrocarbon materials are not observable in process NMR instruments. In order to be observed the molecules under analysis must be entirely in the liquid state and must be above a nominal viscosity threshold. In heavy or waxy petroleum streams the samples must be heated to approximately 80 °C to lower viscosity and ensure melting and solubility of waxy components. 

Boghead coal nonbanded coal in which the liptinite (the waxy component) is predominantly alginite. 

It is the waxy component of the primary wall that must be partially removed to allow the finishing and dyeing chemicals to access the body of the fiber. Inside the primary wall, a thin layer, called the winding layer (Figure 5.29), consists of bands of helical microfibrils that are laid down in a lacy network, which has been associated both with the primary wall [271] and with the secondary wall [99,272]. 

Sometimes sodium or potassium chloride (0.18-1.0%) is added to the desizing bath for pancreative enzymes to get its full activity. For malt a-amylase calcium ion is effective and sequestering agent must be avoided in the desize bath. These salts are particularly used for desize mixture by affording heat protection to enzyme, increased stability of the enzyme and efficiency. On the other hand, heavy metal ions such as copper, iron etc. may combine with enzyme and inhibit its activity [8]. Sometimes hydrocarbon solvents such as xylene (50 ml/1) along with suitable emulsifier (4 g/1) are also added to facilitate removal of waxy components of the size. 

In catalytic de-waxing, special shape-selective catalysts are used to selectively hydrocrack only the straight-chain alkanes to low boiling point by-products. Since it is the linear alkanes that comprise the bulk of the waxy components in the lube boiling range, the oil is effectively de-waxed. There are differences in the composition and properties of base oil de-waxed by catalytic solvent processes because of different selectivities. 

Lipids are hydrolysed for example, wax esters are converted into their constituent fatty acids and alcohols. The less soluble components tend to exhibit the greatest inhibition to ingress of hydrolytic enzymes, and so are the most stable towards biodegradation. The waxy components forming the cuticles of plant leaves and stems are among the best preserved biomacromolecules over geological periods (see Section 4.4.la).The transformations of lipids are examined in more detail in Chapter 5. 

The pre-treatment The yarn or cloth is cleaned from fatty and waxy components by treatment of the textile with soda or sodium hydroxide solution. Often the textile is also bleached, for example with chlorine [20]. 

The largest industrial SRNF plant is installed in the petrochemical industry (Bhore et al., 1999). Wax is a monoester of fatty acids that severely modifies the properties of lube oil and must therefore be removed (Hart et al., 1995). The traditional process of dewaxing involved the cooling of a hydrocarbon mixture in solvent or solvent mixtures (methyl ethyl keton, acetone) to temperatures typically ranging from —5 to — 18°C. In this chilling section, waxy components coagulated and were precipitated or filtered the solvent in the filtrate was removed by evaporation and reused in the process (Cuperus and Ebert, 2002). 

M. forms white crystals. Piu m. (99%) is normally not used in practice. Broader cuts with a high content of m. are used in ointments as a waxy component and as starting material for derivatives (- surfactants). 

The leaves and fruit of many plants bear a waxy coating made up of alkanes that prevents loss of water In addition to being present m beeswax (see Problem 2 6) hen triacontane CH3(CH2)29CH3 is a component of the wax of tobacco leaves... 

A variety of waxy hydrophobic hydrocarbon-based soHd phases are used including fatty acid amides and sulfonamides, hydrocarbon waxes such as montan wax [8002-53-7], and soHd fatty acids and esters. The amides are particularly important commercially. One example is the use of ethylenediamine distearamide [110-30-5] as a component of latex paint and paper pulp blackHquor defoamer (11). Hydrocarbon-based polymers are also used as the soHd components of antifoaming compositions (5) examples include polyethylene [9002-88-4], poly(vinyl chloride) [9002-86-2], and polymeric ion-exchange resins. 

Hurst (19) discusses the similarity in action of the pyrethrins and of DDT as indicated by a dispersant action on the lipids of insect cuticle and internal tissue. He has developed an elaborate theory of contact insecticidal action but provides no experimental data. Hurst believes that the susceptibility to insecticides depends partially on the cuticular permeability, but more fundamentally on the effects on internal tissue receptors which control oxidative metabolism or oxidative enzyme systems. The access of pyrethrins to insects, for example, is facilitated by adsorption and storage in the lipophilic layers of the epicuticle. The epicuticle is to be regarded as a lipoprotein mosaic consisting of alternating patches of lipid and protein receptors which are sites of oxidase activity. Such a condition exists in both the hydrophilic type of cuticle found in larvae of Calliphora and Phormia and in the waxy cuticle of Tenebrio larvae. Hurst explains pyrethrinization as a preliminary narcosis or knockdown phase in which oxidase action is blocked by adsorption of the insecticide on the lipoprotein tissue components, followed by death when further dispersant action of the insecticide results in an irreversible increase in the phenoloxidase activity as a result of the displacement of protective lipids. This increase in phenoloxidase activity is accompanied by the accumulation of toxic quinoid metabolites in the blood and tissues—for example, O-quinones which would block substrate access to normal enzyme systems. The varying degrees of susceptibility shown by different insect species to an insecticide may be explainable not only in terms of differences in cuticle make-up but also as internal factors associated with the stability of oxidase systems. 

Details are given of ways of obtaining energy from the pyrolysis of disposable syringes. The waxy product was chemically modified with maleic anhydride and tested in the processing of PP/LLDPE blends in a rheometer or twin-screw extruder. Compatibility of components in binary or ternary blends and DSC results are discussed. 35 refs. 

Of all the elements, phosphorus is the only one that was first isolated from a human source. The element was extracted from human urine in 1669 using an unsavory process After a sample of urine was allowed to stand for several days, the putrefied liquid was boiled until only a paste remained. Further heating of the paste at high temperature produced a gas that condensed to a waxy white solid when the vapor was bubbled into water. It wasn t until 1779 that phosphorus was discovered in mineral form, as a component of phosphate minerals. 

Although it has been found that the separated amylose component can be readily orientated to yield fiber patterns, amylopectin usually gives poor or amorphous patterns. In the granule, however, amylopectin does exhibit crystallinity, since waxy maize starch gives a diffraction pattern and other waxy starches behave similarly.193 -195 (This suggests that the branch points in the amylopectin molecule may be in the amorphous part of the granule.)... 

The only example of this technique applied to the amylose component is that already described, of the action of Z-enzyme on the /3-limit dextrin. In the case of amylopectin, enzymic methods enable a distinction to be made between the proposed laminated and highly ramified structures (I and III, in Fig. 1, page 352). The method used by Peat and coworkers101 involves the successive action of /3-amylase and R-enzyme on waxy maize starch. /3-Amylolysis will degrade A-chains down to two or three units from the 6 —> 1-a-D interchain linkages. These latter linkages will protect the... 

Products.—Considerable information concerning the mechanism of the enzymic hydrolysis of starch has been obtained from investigations of the action of purified maltase-free pancreatic amylase on a number of different substrates. The substrates studied were ordinary unfractionated but exhaustively defatted10 potato and com starches a branched chain substrate, waxy maize starch and amylose, the linear component of corn starch.41 69 eo f4 These investigations included comparisons not only of the rates of the hydrolysis of the different substrates but also of the products formed from them. 

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