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Nickel direct contact

Biesterbos J, Yazar K, Lid6n C. Nickel on the Swedish market follow-up 10 years after entry into force of the EU Nickel Directive. Contact Dermatitis 2010 63(6) 333-9. [Pg.365]

Heat exchangers that utilize copper coils are potential candidates for galvanic corrosion due to dissolved copper salts interacting with the galvanized steel shell. This problem can be avoided by nickel plating the coils. The coils then can be separated from direct contact with the vessel via insulation. Also, it is preferable to conduct the water on the tube side of heat exchangers. [Pg.42]

A total of four Co and Fe based alloys were procured from a commercial source. Disks were punched from the foil and mounted into VCR vacuum fittings, with a nickel gasket on one surface and the sample in direct contact with the VCR sealing surface on the other. The sample assemblies were leak tested and verified leak tight to 2x10 7 sscm He prior to intallation in the permeation test apparatus. [Pg.151]

The most common adverse health effect of nickel in humans is an allergic reaction to nickel. People can become sensitive to nickel when jewelry or other things containing nickel are in direct contact with the skin. Wearing earrings containing nickel in pierced ears may also sensitize people to nickel. Once a person is sensitized to nickel, further contact with the metal will produce a reaction. The most common reaction is a skin rash at the site of contact. In... [Pg.17]

Currently interest has now been directed toward a similar high temperature system, the ZEBRA Battery, which also uses P-alumina as a Na ion conductor. The sulfur electrode is replaced by nickel chloride or by a mixture of ferrous and nickel chlorides. Contact between the NiCl2 electrode and the solid electrolyte is poor as they are both solids, and current flow is improved by adding a second liquid electrolyte (molten NaAlCb) between this electrode and the P-alumina. The overall cell reaction is now ... [Pg.235]

A sheet iron vessel, A, with riveted joints and a double bottom, has a grooved rim B into which fits a cover C. The cover has three tubular openings fitted with rubber stoppers—one D is an inlet for ammonia, another E is the outlet, and the third is for a thermometer F. The ammonia inlet-tube leads into a nickel dish O which contains clean dry sodium, and stands upon a little tripod to prevent direct contact with the hot bottom of the iron vessel A. [Pg.253]

Skin sensitization is believed to occur as a result of nickel binding to proteins (particularly on the cell surface) and hapten formation. Essentially, the body perceives the nickel-protein complex as foreign and mounts an immune reaction to it. For example, sweat may react with the nickel in plated jewelry that comes in direct contact with skin dissolved metal may penetrate and react with proteins in the skin and lead to immune sensitization. Nickel may substitute for certain other metals (especially zinc) in metal-dependent enzymes, leading to altered protein function. High nickel content in serum and tissue may interfere with both copper and zinc metabolism. It also readily crosses the cell membrane via calcium channels and competes with calcium for specific receptors. [Pg.1805]

Oxine copper is an organometallic preservative comprising 10% copper-8-quinolinolate and 10% nickel-2-ethylhexoate that offers protection against sapstain and moulds. It has low mammalian toxicity. The treated wood has a greenish brown colour and little or no odour. Of particular interest, when used alone it is permitted by the U.S. Food and Drug Administration for treatment of wood used in direct contact with food. [Pg.315]

The electrodes are flat. The anode is composed of porous sintered nickel along with additives, which inhibit the loss of surface area during operation. The anode is in direct contact with the electrolyte matrix. The cathode is a porous nickel oxide, which is initially fabricated in the form of a porous sintered nickel and is subsequently oxidized during the cell operation. [Pg.1748]

As with soft metal gaskets, volatile components in the braze alloy (including phosphorus) should be avoided. A special subset of brazing is solid-state brazing, or intermetaUic diffusion. This occurs spontaneously, albeit slowly, when miscible metals are placed in direct contact. Examples of suitable metals for solid-state brazing to the membrane and module include copper, iron, silver, and nickel [7]. [Pg.147]

Only a few general remarks The organic film can be a thicker film of paint or a very thin film not distorting the geometry of the parts. In the latter case, a thin wax film (10-100 nm) is applied to the surface. The film is hydrophobic and keeps moisture away from the surface. The film can also prevent direct contact of the metal deposited with the human sldn. This is important with toxic or problematic metals like chromium and nickel. [Pg.590]

Schmitt [52] reviewed the effect of elemental sulfur on corrosion of construction materials (carbon steels, ferric steels, austenitic steels, ferritic-austenitic steels (duplex steels), nickel and cobalt-based alloys and titanium. Wet elemental sulfur in contact with iron is aggressive and can result in the formation of iron sulfides or in stress corrosion cracking. Iron sulfides containing elemental sulfur initiate corrosion only when the elemental sulfur is in direct contact with the sulfide-covered metal. Iron sulfides are highly electron conductive and serve to transport electrons from the metal to the elemental sulfur. The coexistence of hydrogen sulfide and elemental sulfur in aqueous systems, that is, sour gases and oils, causes crevice corrosion rates of... [Pg.673]

In 1988, five cases were reported occurring at 10 [29, 30] and 11[29, 31, 32] years after implantation. The sarcomas included two osteosarcomas, two malignant fibrous histiocytomas, and one synovial sarcoma. Two of these were soft tissue in a location with no direct association with the implant, yet in the case reported by Tait et al [32] there was evidence of nickel within tumor cells. The remaining three patients all had direct contact with either the cement or implant with the tumor originating in bone. [Pg.535]

Impurities in the rare metals produced by the iodide process can generally be reduced to a few tens of parts per million or less, for each element, provided care is taken in the selection of materials of construction. This initial advantage over other processes arises from the fact that the rare metals are produced without direct contact with a crucible or other container. Elements with volatile iodides should clearly be avoided in locations where the temperature is appropriate for attack by iodine vapour. Similarly, the crude feed should be as free from such elements as possible. For example, the whole of the zirconium impurity in a crude titanium feed would be carried over into the product, and vice versa, since the iodide process is equally suitable for the impurity as for the rare metal being purified. A large fraction of the iron and aluminium would be transferred, but decontamination factors from other elements such as nickel, chromium, carbon silicon and nitrogen are usually of the order of 10 to 100. [Pg.306]

Nickel was named Contact Allergen of the Year in 2008 by the American Contact Dermatitis Society, and the rates of positive patch tests have been increasing year by year [83 ]. The European Union (EU) adopted the EU Nickel Directive in 1994 it limits nickel release from body piercing equipment to <0.2 micrograms/cm /week [84 ]. Despite this, of 95 nickel-allergic patients with dermatitis in Denmark, 70 had 151 metallic items, 66 of which contained nickel, detected using the dimethyl-glyoxime test, and nearly all had been purchased or acquired after the introduction of the EU Nickel Directive [85 ] however, few were items covered by the Directive and the rates of release were not studied (Table 2). [Pg.358]

The dimethylglyoxime test (Fisher s test) is a simple test for nickel release, and it may be used for jewellery and for other objects that come in direct contact with the skin (Feigl 1972 Fisher 1986). In many countries the dimethylglyoxime test is now commercially available in pharmacies or chemist s shops. [Pg.530]

For the electrochemical plating of silver, a 99.9% silver anode is used with an electrolyte composed of [Ag(CN)2] and other required additives. Silver should not come into direct contact with steel or severe corrosion can occur. Steel parts can be protected by first coating with copper or nickel. Silver coating is commonly used for flatware, hol-loware, jewelry, electrical, and mechanical applications. Chemical methods are available to apply silver as a coating to plastic or glass. [Pg.326]

Piping, valves, and other equipment used in direct contact with anhydrous boron trichloride should be of stainless steel. Carbon steel may be used in some areas if the temperature remains below 265°F (129°C). Monel and other nickel alloys also offer good resistance. In the presence of moisture, the formation of hydrochloric acid will cause most metals to corrode. Platinum, silver, or tantalum offer the best resistance. [Pg.276]


See other pages where Nickel direct contact is mentioned: [Pg.3]    [Pg.99]    [Pg.90]    [Pg.114]    [Pg.180]    [Pg.368]    [Pg.16]    [Pg.644]    [Pg.425]    [Pg.96]    [Pg.1805]    [Pg.304]    [Pg.102]    [Pg.495]    [Pg.135]    [Pg.90]    [Pg.728]    [Pg.393]    [Pg.241]    [Pg.537]    [Pg.439]    [Pg.302]    [Pg.530]    [Pg.868]    [Pg.9022]    [Pg.1166]    [Pg.53]    [Pg.234]    [Pg.48]   
See also in sourсe #XX -- [ Pg.73 ]




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Contact nickel

Direct contact

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