Hemp nettle

Hohlimg, /. cavity, hoUew, excavation. Hohl-vene, /. (Anat.) vena cava, -walze, /. hollow cylinder or roll, -welle, /. hollow shaft, -zahn, m. (Bot.) hemp nettle, -ziegel, m. hollow brick (or tile), -zirkel, m. inside calipers, -zylinder, m. hollow cylinder. 

Some of the more interesting and attractive groups of native species include the skullcaps (Scutellaria spp.), physostegias (Physostegia spp.), hemp-nettles (Stachys spp.), sages (Salvia spp.), horse-mints or bergamots (Monarda spp.), bugle-weeds (Lycopus spp.), and tme mints (Mentha spp.). 

Scientists and engineers at the University of Exeter are investigating whether natural fibers tike hemp and sisal could be used to make sustainable and eco-friendly brake pads [39]. The technology of brake pads turned green with the replacement of asbestos by aramids (hke Kevlar of DuPont) in the 1980s. Kevlar is very expensive and eco-friendly alternatives like hemp, jute, sisal, nettle, and flax are much, much cheaper. A breakthrough in this application will revolutionize brake manufacture and protect the environment. 

Hemp rope, once widely used, has largely been replaced by iiylon cord. The flexibility and mechanical strength of hemp, a nettle plant fiber, also characterize nylon synthetic and several other inorganic fibers in common use. 

Marijuana is derived from the Indian hemp plant, Cannabis sativa, a member of the Cannabaceae family and the Urticales (nettle) order. Some botanists claim that this genus contains as many as three other species C. indica, C. ruderalis, and even Humulus lupulus, the hops plant. Other botanists insist that the differences between plants reflect simple variations, not different species. 

There are many kinds of natnral fibers, snch as bast fibers (flax, hemp, jute, kenaf, ramie, nettle, and mesta), leaf fibers (sisal, heneqnen, pineapple, abaca, oil palm, and screw pine), seed fibers (cotton), frnit fibers (coconnt hnsk, or coir), and stalk fibers (straw of varions kinds). They are not nsed for commercial WPG, primarily on economical reasons (except maybe Procell, see Table 1.1). Most of these fibers have fonnd applications in established indnstries, snch as textile indnstry (cotton, flax, jnte, ramie, hemp, and sisal) and paper indnstry (straw). 

Loading nose, 226, 232, 233, 236, 238, 239, 241, 242, 245, 253, 256, 265, 274 Long alkyl chain alkoxysilanes, 172 Long cellulose fiber, 79, 92, 98 Long natural fiber, 110 Abaca, 110 Bast fibers, 110 Cost of, no Cotton, 110 Flax, no Fruit fibers, 110 Hemp, no Henequen, 110 Jute, no Kenaf, 110 Leaf fibers, 110 Mesta, no Nettle, no Pineapple, 110 Ramie, 110 Seed fibers, 110 Sisal, no Stalk fibers, 110... 

The use of natural fibres, both plant and animal, to meet our needs plays a significant role throughout history. Wool, as a representative of animal fibres, has been used since the dawn of mankind. One of the oldest reeorded uses of plant fibre for fabrics is that of hemp, already being cultivated in China in 2800 BC. The common nettle is probably the best example of how society s interest in natural fibres fluctuates along the years. It was used for cloth in Neolithic times, and then became important for nets for fishing. Nettle cloth was manufactured in Scandinavia and Scotland until the nineteenth century and shortages of... 

Fig. 4.5 Principal centres of fibre production 1 flax, 2 hemp, 3 sunn, 4 ramie, 5 jute, 6 kenaf, 7 roseUe, 8 sisal, 9 abaca, 10 nettle, 11 coir, 12 cantala, 13 henequen, 14 kapok, 15 urena,...

Bast fibers - such as flax, hemp, kenaf, ramie, jute, and nettle... 

Fibrous plants can be classified from their purpose point of view. In this classification system, bast fibers are classified into group of fibrous plants cultivated just for fiber production. The second group of the system contains plants grown for other goods, for example, fruits - coconut production, and fibers constitutes only a by-product of the plant - coir (Pickering 2008). Another classification system indicates that most of the technically important bast fibers are obtained not only from plants cultivated in agriculture, such as flax, hemp, or ramie, but also from wild plants, such as nettle. 

Properties related to bast fibers shape are shown in Table 4.4. Ramie, nettle, and flax are characterized by the highest density, but kenaf and isora show the lowest density. The longest technical fiber you can find is hemp, but ramie elementary fiber is the longest and the thickest. 

Faruk et al. [3] classify the plants, which produce natural fibers, into two groups according to their utilization primary and secondary. Primary plants are grown for their fiber, while secondary plants are grown for other causes where the fiber is a byproduct. Primary plants include jute, hemp, kenaf, and sisal, etc. Some conventional examples of secondary plants are pineapple, oil palm and coir. Some novel secondary plant examples include corn, okra, nettle, etc. This chapter is focused on these novel secondary plants, which give fiber as a by-product and have been the subject of limited research endeavor in the literature so far. 

Bacci et al. [39] treated nettle stalks with boiling soda solution xmtil the bark, the source of fiber, was easily removed from the core of the stalk than performed alkalization treatment on the bark. Enzymatical fiber retting maybe faster and more reproducible than the traditional biological fiber retting methods and is extensively studied for flax and hemp extraction enhancement [39]. 

Bast (stem) fibers Flax, Hemp (and Sunhemp), Kenaf, Jute, Mesta, Ramie, Urena, Roselle, Papyrus, Cordia, Indian Malow, Nettle... 

All bast (stem) fibers (flax, kenaf, ramie, nettle, hemp, jute) as well as hard fibers (caroa, sisal) are suitable as for reinforcing fibers for natural fiber reinforced polymer composites, if they have a high tensile modulus and sufficient tensile strength. In addition to cultivation site, type and harvest, the properties of natural fibers depend significantly on the fiber extraction method. An extraction to technical fiber grades, i.e. production of bundles with different number of single fibers, is generally sufficient for use in plastics composites. The properties of such extracted fibers may be described as follows ... 

Natural origin eeo fibre - Organic cotton, organic silk, Ahimsa silk, organic wool. Hemp, bamboo, Kenaf, jute, Sasawashi, Nettle, Sisal, Coconut fibre or Coir, [Banana] fibre. Ramie and Mesta/Roselle. Highly processed natural origin fibre - Rayon type Modal, Lyocell/ Tencel, Ingeo, Seacell. 

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