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Stem fibres

Seed fibres from cotton and stem fibres from flax were probably the first to be commonly woven into textiles. Linen (from flax) was the every-day fabric of ancient Egypt, and the plant was the first cultivated source of textile fibres in Europe. While cotton only became popular in Europe a few centuries ago, its... [Pg.57]

Bast or stem fibres These fibres come from the inner bark of the stem of plants. Common examples are jute, flax, hemp, kenaf and ramie. [Pg.402]

Cellulosic fibres from vegetable sources other than cotton and wood are used in a variety of textile and industrial products. These fibres are mostly obtained either from the leaves of tropical plants or from the stems of reed-like plants. Leaf fibres are generally stiff ( hard fibres ) and are used mostly for cordage. Stem fibres (also known as bast fibres) are usually finer ( soft fibres ) and find use in textile applications. The cellulose content of these materials is usually in the range 70—90% (on dry weight). The more important commercial products and their principal usage are shown below. [Pg.248]

Diederichsen, A., Ulrich, A., 2009. Variability in stem fibre content and its association with other characteristics in 1177 flax (Unum usitatissimum L.) genebank accessions. Ind. Crops Prod. 30, 33-39. [Pg.186]

It is important to note that diet is a complex mixture that contain compounds with varying activity. Chemical stimulators of colon cancer growth include bile acids, 1,2-diglycerides and prostaglandins which stem from consumption of fat. In contrast, fruits and vegetables contain substances such as carotenoids, flavonoids and fibre, which may inhibit cancer cell growth, and the risk of colon cancer appears to be mirrored by the ratio of plant sterols to cholesterol in the... [Pg.126]

Fig. 2.20 Efferent pathways into bulb showing (a) cholinergic (ACh) fibres projecting to MOB from basal forebrain nuclei. AON = ant. olfactory nucleus, OT = olfactory tract, DB = diagonal band nuc. (from Davis et al., 1978). (b) Nor-Adrenalin input to AOB, via MFB pathway from brain stem centres (nuclei A1-2, A6) (from Keveme, 1971). Fig. 2.20 Efferent pathways into bulb showing (a) cholinergic (ACh) fibres projecting to MOB from basal forebrain nuclei. AON = ant. olfactory nucleus, OT = olfactory tract, DB = diagonal band nuc. (from Davis et al., 1978). (b) Nor-Adrenalin input to AOB, via MFB pathway from brain stem centres (nuclei A1-2, A6) (from Keveme, 1971).
The earliest polymeric cationic aftertreatments stemmed from the development of crease-resist finishes for cellulosic fibres. One such, promoted specifically for its colour fastness improvements when applied as an aftertreatment to direct dyeings, was a condensation product of formaldehyde with dicyandiamide (Scheme 10.82). Many similar compounds followed, such as condensation products of formaldehyde with melamine (10.212), polyethylene imine) with cyanuric chloride (10.213) and alkyl chlorides with polyethylene imine) (10.214 R = alkyl). [Pg.237]

The parasympathetic nervous system. Here the postganglionic fibres are always short. The preganglionic fibres are long and pus almost up to the muscle or gland to be innervated. The preganglionic fibres arise from the brain stem (cranial nerves VII, IX and X), from the tectal region (cranial nerve III which supplies the eye, p. 38), and from the sacral region. [Pg.46]

Polycrystalline morphology of double habit consisting offibrous crystals overgrown epitaxially by lamellar crystals, the stems of which are parallel to the fibre axis. [Pg.88]

Five- to six-month-old tobacco plants (Nicotiana tabacum var. Samsun) grown in a glasshouse at 20°C were used for this study. Commercial synthetic substrates employed both for histochemical and biochemical assays were guaiacol, p-phenylenediamine-pyrocatechol (PPD-PC), 3-3 di-aminobenzidine (DAB), tetramethylbenzidine (TMB) and syringaldazine. Isopropylamine and monosodium salts of ferulic acid were also used as substrates as well as their / -fluorinated analogues substituted with a fluorine atom on the / -carbon (Fig. 1). Histochemical observations were done on hand-made transverse sections of fresh tobacco stems. Biochemical assays were performed separately on bark (inner cortical parenchyma, phloem and fibres) and xylem fractions. Technical data of incubation, enzyme extraction, spectrophotometric and electrophoretic assays were given elsewhere (5-7). Synthesis of fluorinated compounds was performed as previously described (4). [Pg.194]

Special characteristics Mainly in warm and arid regions Stems often sympodial Stems joined at the nodes Xylem with vessels Tracheids and fibres Hairs... [Pg.54]

In Great Britain, according to the patents of Picton [6] small flakes of sheet wood-cellulose have been nitrated, while in the United States shredded cellulose prepared by the Stem method [7] was most widely used (shreds made of loosely felted cellulose fibres in a special machine). This last form of cellulose is especially suitable for uniform penetration and imbibition of the nitrating acid. Normal nitrators, as used for linters, are also suitable for nitrating this type of cellulose. [Pg.367]

Filtration of Hot Solution (see also Filtration).—This operation is usually necessary in order to remove insoluble impurities, filter fibres, etc. When the substance does not separate rapidly from the hot solution, and the liquid filters quickly, the solution may be filtered through an ordinary funnel with a short stem, fitted with a folded filter paper (Pig. 1). Both funnel and paper should previously be warmed in a steam bath. Or, the solution may be filtered with suction, using suitable types of apparatus (Pigs. 27,28). The funnel and filtering medium should be previously warmed. When the filtrate is collected in a thick glass suction flask,... [Pg.10]

A, Lycopodium spores and ragweed pollen on wheat stems (Aylor Ferrandino, 1985) , fly ash particles on steel fibres (Ellenbecker et al., 1980) O, polystyrene particles on pine needles (Little, 1979). [Pg.203]

Features Erect, smooth, angular, brown-spotted stem, two to three feet high. Leaves opposite, stalked, smooth, serrate, usually in three or five segments. Flowers (July to September) in terminal heads, small, tawny. Numerous seeds, four-cornered, reflexed prickles. Root tapering, many-fibred. [Pg.27]

Features Stem erect, striate, tough, two to three feet high. Leaves alternate, lower lyrate-pinnatifid, stalked upper bi-pinnatifid, sessile. Yellow flowers (July and August) florets of the ray smooth, of the disc hairy. Root consists of many long, thick fibres. [Pg.78]

In the brain stem, TRPV1 receptor activation, similarly to P2X3 receptor activation (see above), facilitated spontaneous glutamate release in a tetrodotoxin- and Cd2+-insensitive manner, even though the two presynaptic receptors were located on different primary afferent fibres (Jin et al. 2004). Action potential-dependent glutamate release, in contrast, was reduced by TRPV 1 activation (Doyle et al. 2002). In paraventricular neurons, TRPV 1 receptor activation facilitated spontaneous glutamate release in a tetrodotoxin- and Cd2+-insensitive way, but in that case evoked glutamate release was enhanced too (Li et al. 2004). [Pg.500]

In cestodes, most, perhaps all, of the neural elements are found in the ganglia of the scolex and the main nerve tracts. In these, the cell bodies are arranged peripherally around a core made up of a tangled mass of neuronal processes often referred to as neurites because it is impossible to distinguish between axons and dendrites. This mass constitutes the so-called neuropile . Like all differentiated cells in cestodes - and probably in all invertebrates - nerve cells are incapable of mitosis and hence new nerve cells must arise directly from the germinative ( = stem) cells (276). In D. dendriticum, the neuropile is composed of a dense network of unmyelinated nerve fibres with no extracellular stroma between the fibres (277). The fibres differ mainly in the content of different types of vesicles, which can be dense-core, small clear or large clear vesicles. The structure of synapses is discussed further on pp. 25—7. [Pg.24]

It shall be manufactured under hygienic conditions, light to dark brown in colour, and the flavour should be characteristic of tamarind fruit. No burnt flavour should be present. It shall be free from harmless extraneous vegetable materials (fibre and rind common to tamarind, and stems up to... [Pg.370]


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See also in sourсe #XX -- [ Pg.248 ]

See also in sourсe #XX -- [ Pg.289 ]

See also in sourсe #XX -- [ Pg.429 ]




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Bast/stem fibres

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