Fibers copper

Typical concentration range stainless steel fiber - 1-7 wt%, 30 wt% or more graphite, 15-50 wt% carbon black for conductive materials, glass spheres and fibers up to 70 wt%, carbon fiber - 20 wt%, silicon oxide and silicates up to 40 wt%, LCP up to 30 wt%, wollastonite - 40 wt% (can be used in conjunction with glass fiber,copper/polyamide-11 composite was made with 90 wt% spherical copper powder ... 

Hydrolysis resistant polyamide-610 compositions comprising glass fibers, copper, and nucleating agent. The nucleating agent is carbonblack/talc mixture. ... 

The coating of electric wires for magnets has been described by Feit Using a similar set-up as used for the coating of optical fibers, copper wire was coated with a mixture of a urethane monomethacrylate and a diurethane dimethacrylate. At intensities of a few mW cm, drawing speeds of 2 cm s were obtained. Wires, coated with three layers of this material exhibited breakdown voltages of about 2kV. 

Figure 9.6. Cross-section of graphite-fiber/copper composites with NbC interface after thermal exposure. (Photograph courtesy of Rocketdyne, Canoga Park,...

NOTE WELL The biological availability of zinc in different foods varies widely meats and seafoods are much better sources of available zinc than vegetables. Zinc availability is adversely affected by phytates (found in whole grains and beans), high calcium, oxalates (in rhubarb and spinach), high fiber, copper (from drinking water conveyed in copper piping), and EDTA (an additive used in certain canned foods). 

Electrically Conducting Fibers. FlectricaHy conducting fibers are useful in blends with fibers of other types to achieve antistatic properties in apparel fabrics and carpets. The process developed by Nippon Sanmo Dyeing Co., for example, is reportedly used by Asahi in Casbmilon 2.2 dtex (2 den) staple fibers. Courtaulds claims a flame-resistant electrically conductive fiber produced by reaction with guanadine and treatment with copper sulfide (97). 

The second ceUulosic fiber process to be commercialized was invented by L. H. Despeissis (4) in 1890 and involved the direct dissolution of cotton fiber in ammoniacal copper oxide Uquor. This solvent had been developed by M. E. Schweizer in 1857 (5). The cuprammonium solution of ceUulose was spun into water, with dilute sulfuric acid being used to neutralize the ammonia and precipitate the ceUulose fibers. H. Pauly and co-workers (6) improved on the Despeissis patent, and a German company, Vereinigte Glanstoff Eabriken, was formed to exploit the technology. In 1901, Dr. Thiele at J. P. Bemberg developed an improved stretch-spinning system, the descendants of which survive today. 

Asahi Chemical Industries (ACl, Japan) are now the leading producers of cuprammonium rayon. In 1990 they made 28,000 t/yr of filament and spunbond nonwoven from cotton ceUulose (65). Their continuing success with a process which has suffered intense competition from the cheaper viscose and synthetic fibers owes much to their developments of high speed spinning technology and of efficient copper recovery systems. Bemberg SpA in Italy, the only other producer of cuprammonium textile fibers, was making about 2000 t of filament yam in 1990. 

The high purity anhydrous copper(II) fluoride must be stored ia a tightly closed or sealed container under an atmosphere of argon. The dihydrate may be stored ia polyethylene-lined fiber dmms. The ACGIH (1992—1993) adopted toxicity value for copper as Cu is 1 mg/m, and for fluorides a F , 2.5 mg/m. ... 

Germanium tetrachloride refined for use in making optical fibers is usually specified to contain less than 0.5 to 5 ppb of each of eight impurities vanadium, chromium, manganese, iron, cobalt, nickel, copper, and zinc. Limits are sometimes specified for a few other elements. Also of concern are hydrogen-bearing impurities therefore, maximum limits of 5 to 10 ppm are usually placed on HCl, OH, CH2, and CH contents. 

The supplanting of germanium-based semiconductor devices by shicon devices has almost eliminated the use of indium in the related ahoy junction (see Semiconductors). Indium, however, is finding increased use in III—V compound semiconductors such as indium phosphide [22398-80-7] for laser diodes used in fiber optic communication systems (see Electronic materials Fiber optics Light generation). Other important indium-containing semiconductors include indium arsenide [1303-11-3] indium antimonide [1312-41 -0] and copper—indium—diselenide [12018-95-0]. 

In the early 1990s, there were more than 9 x 10 km of fiber-optical telecommunication links in practical use in the United States. In addition, many other countries, notably Canada, Japan, and western Europe, have installed extensive fiber-optic communication systems. There are several transoceanic fiber-based telephone cables. Fibers are in use for intracity telephone links, where bulky copper [7440-50-8] wine is replaced by thin optical fibers. This allows crowded conduits in large cities to carry more messages than if copper wine were used. Fiber optics are used for intercity long-haul telephone links, for interoffice tmnk lines, and have replaced many microwave communication links. 

These appHcations include many of the shorter-distance communication links, such as the automated operation of all the environmental controls in a large commercial building. Fiber optics can replace copper wire at a savings in space and cost for many of these appHcations. 

For many electronic and electrical appHcations, electrically conductive resias are required. Most polymeric resias exhibit high levels of electrical resistivity. Conductivity can be improved, however, by the judicious use of fillers eg, in epoxy, silver (in either flake or powdered form) is used as a filler. Sometimes other fillers such as copper are also used, but result in reduced efficiency. The popularity of silver is due to the absence of the oxide layer formation, which imparts electrical insulating characteristics. Consequently, metallic fibers such as aluminum are rarely considered for this appHcation. 

Phthalocyanine Dyes. In addition to their use as pigments, the phthalocyanines have found widespread appHcation as dyestuffs, eg, direct and reactive dyes, water-soluble dyes with physical or chemical binding, solvent-soluble dyes with physical or chemical binding, a2o reactive dyes, a2o nonreactive dyes, sulfur dyes, and wet dyes. The first phthalocyanine dyes were used in the early 1930s to dye textiles like cotton (qv). The water-soluble forms Hke sodium salts of copper phthalocyanine disulfonic acid. Direct Blue 86 [1330-38-7] (Cl 74180), Direct Blue 87 [1330-39-8] (Cl 74200), Acid Blue 249 [36485-85-5] (Cl 74220), and their derivatives are used to dye natural and synthetic textiles (qv), paper, and leather (qv). The sodium salt of cobalt phthalocyanine, ie. Vat Blue 29 [1328-50-3] (Cl 74140) is mostly appHed to ceUulose fibers (qv). 

Copper-based thermal stabilizers are also effective photostabilizers for nylon. They can be added before polymerization, or the soluble salts (eg, CuSO can be appHed to fibers as part of the finish or to fabrics as post-treatments. The effectiveness of the copper salt—alkah haUde system added to prepolymer in retarding phototendering and photoyeUowing of the resulting spun yam is illustrated in Figure 5. 

At the lowest level, the aetwork is the physical medium that connects the various pieces of equipmeat. This can be copper wire, often known as Ethernet, or optical fiber, ie, fiber-distributed data iaterface (EDDI). Networks allow transmission of data at nominal speeds of 10 to 100 megabits per second, depending on the physical medium used. 

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