Fast fibers

Key elements of the eholinergie system include a neurotransmitter, ACh, an enzyme, AChE, that hydrolyzes ACh, and an enzyme, ChAT, that synthesizes ACh. All skeletal muscles eontain these eholinergie eomponents, but their quantities ean signifieantly vary from muscle to muscle, i.e. fast fiber eontaining musele has greater values than the slow fiber or mixed fiber eontaining musele. 

I Depolarization (phase 0) is due to Na influx in fast fibers and due to Ca influx in SA and AV nodal i cells. Class I antiarrhythmic drugs block Na influx and class IV antiarrhythmics block Ca " influx. 

It has been established that electrospinning a polymer solution containing well-dispersed carbon nanotubes leads to nanocomposite fibers with the embedded carbon nanotubes oriented parallel to the nanofiber axis due to the large shear forces in a fast fiber-drawing process. Table 1 lists most of the polymer/CNT composite nanofibers produced by electrospining, along with their fiber diameters and tensile properties. 

Ultra-Fast Fiber Lasers Principles and Applications with MATLAB Models,... 

Fiber-coupled CCD Process Analyzer 450-830 Trace Fast Fiber-coupled probe head Research lab to process 1-2 cm" accuracy Low concentration Qualitative Quanitative Process control... 

Key elements of the cholinergic system include a nemo-transmitter, ACh an enz5une, AChE, which hydrolyzes ACh and an enzyme, ChAT, which synthesizes ACh. All skeletal muscles contain these cholinergic components, but their quantities can significantly vary from muscle to muscle i.e., fast fiber-containing muscle has greater values than slow fiber-or mixed fiber-containing muscle. 

The use of 2-aminothiazole derivatives as dyeing compounds is direct related to the development of synthetic fibers. Some typical examples are given in Table VI-14. The importance of these dyes lies in their performance on acetate fibers. They have excellent fastness to gas fumes, produce a bright blue shade, and have a high tinctorial strength. Their only disadvantage is their relatively low light fastness, which does limit their application. 

Dyes with good wet. light, and sublimation fastness for polyesters, nylon, and acetate fibers... 

Dyes polyester fibers fast blue, brown, and red shades... 

Orange dye that gives on qiiaternizalion a new fast-ted dye oti acrylic fibers... 

A series of water-soluble fiber-reactive xanthene dyes has been prepared from the reaction of ben2oxanthenedicatboxylic acid anhydride disulfonic acid with, for example, 3-aminophenyl-P-hydtoxyethyl sulfone to yield dyes, with high brilliance and good fastness properties for dyeing of or printing on leather, wool, sHk, or ceUulosic fibers (53). 

Although the cross-sectional shape of the spinneret hole direcdy affects the cross-sectional shape of the fiber, the shapes are not identical. Round holes produce filaments with an approximately round cross section, but with crenelated edges triangular holes produce filaments in the form of a "Y." Different cross sections are responsible for a variety of properties, eg, hand, luster, or cover, in the finished fabric. Some fibers may contain chemical additives to provide light-fastness and impart fire retardancy. These are usually added to the acetate solution before spinning,... 

Microscopy (qv) plays a key role in examining trace evidence owing to the small size of the evidence and a desire to use nondestmctive testing (qv) techniques whenever possible. Polarizing light microscopy (43,44) is a method of choice for crystalline materials. Microscopy and microchemical analysis techniques (45,46) work well on small samples, are relatively nondestmctive, and are fast. Evidence such as sod, minerals, synthetic fibers, explosive debris, foodstuff, cosmetics (qv), and the like, lend themselves to this technique as do comparison microscopy, refractive index, and density comparisons with known specimens. Other microscopic procedures involving infrared, visible, and ultraviolet spectroscopy (qv) also are used to examine many types of trace evidence. 

Oxidation. Hydrogen peroxide is a strong oxidant. Most of its uses and those of its derivatives depend on this property. Hydrogen peroxide oxidizes a wide variety of organic and inorganic compounds, ranging from iodide ions to the various color bodies of unknown stmcture in ceUulosic fibers. The rate of these reactions may be quite slow or so fast that the reaction occurs on a reactive shock wave. The mechanisms of these reactions are varied and dependent on the reductive substrate, the reaction environment, and catalysis. Specific reactions are discussed in a number of general and other references (4,5,32—35). 

Chrome-tanned leather has chromium bonded to the leather fibers. This chromium can act as a mordant for acid dyes resulting in fast colors and intense shading at the surface of the leather. 

Formaldehyde. Worldwide, the largest amount of formaldehyde (qv) is consumed in the production of urea—formaldehyde resins, the primary end use of which is found in building products such as plywood and particle board (see Amino resins and plastics). The demand for these resins, and consequently methanol, is greatly influenced by housing demand. In the United States, the greatest market share for formaldehyde is again in the constmction industry. However, a fast-growing market for formaldehyde can be found in the production of acetylenic chemicals, which is driven by the demand for 1,4-butanediol and its subsequent downstream product, spandex fibers (see Fibers, elastomeric). 

Nickel also has been used as a dye site in polyolefin polymers, particularly fibers. When a nickel compound, eg, the stearate or bis(p-alkylphenol) monosulfide, is incorporated in the polyolefin melt which is subsequently extmded and processed as a fiber, it complexes with certain dyes upon solution treatment to yield bright fast-colored fibers which are useful in carpeting and other appHcations (189). Nickel stearate complexing of disperse mordant dyes has been studied (190). 

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