Bismuth-based alloys

On the role of bismuth-based alloys in carbon-supported bimetallic Bi-Pd catalysts for the selective oxidation of glucose to gluconic acid... 

The cores are cast in a split GRP mold, using a bismuth-based alloy, formulated to flow freely and reproduce closely the contours of the mold. When the core has been cast, an uncured RP material shell is placed over it and cured. When the RP shell is cured, the alloy is melted out at I37C (278F), producing a single-piece RP cylinder, with an accurately dimensioned interior. The melted alloy is recovered and recycled. 

S and p are small in metals, leading to small power factors. On the other hand, S is large for semiconductors or insulators but p is too large, so that S lp is again too small. As shown in Figure 4.3, the maximal value for Z can be obtained for intermediate values of the carrier density, close to 10 —10 cm , typical of semiconductors. Three different families have been traditionally used bismuth-based alloys (BiSb, Bi2Te3...) are used for T ranging from 100 K to 450 K, lead telluride materials are... 

The separation and determination of bismuth in mixtures of copper, lead, tin and of cadmium, antimony, silver and copper by ingenious choice of electrolytes and potentials is described by Lingane and Jones (25) and Tanaka (27-29), respectively. Alfonsi (30, 34) has adequately discussed the application of such techniques to the determination of bismuth in lead-tin-base and bismuth-base alloys. 

Solders. In spite of the wide use and development of solders for millennia, as of the mid-1990s most principal solders are lead- or tin-based alloys to which a small amount of silver, zinc, antimony, bismuth, and indium or a combination thereof are added. The principal criterion for choosing a certain solder is its melting characteristics, ie, soHdus and Hquidus temperatures and the temperature spread or pasty range between them. Other criteria are mechanical properties such as strength and creep resistance, physical properties such as electrical and thermal conductivity, and corrosion resistance. 

Backmank S, Karlsson RW (1979) Determination of lead, bismuth, zinc, silver and antimony in steel and nickel-base alloys by atomic-absorption spectrometry using direct atomization of solid samples in a graphite furnace. Analyst 104 1017-1029. 

Nitroparaffins Oxalic acid Oxygen Perchloric acid Inorganic bases, amines Silver, mercury Oils, grease, hydrogen, flammable liquids, solids or gases Acetic anhydride, bismuth and its alloys, alcohol, paper, wood, grease, oils... 

Cu2 O BaCr04, was considered based on the ealed heats of reactions involved, expressed as kilocalories per equivalent wt. However, many other metals were superior to Bi in this respect, and Bi is not known to be used in any US std delay compns for fuzes. DeMent(Ref 10) patented the use of powdered Bi in smoke-producing compns. Coenders(Ref 8) prepd a pyrophoric body by sintering and compacting a powd metal or alloy of a low-bp metal, such as Hg,Zn,Mg,As,Sb or Bi, with powd Ce or Ce alloy so as to produce surface alloying(See also Bismuth Alloys)... 

Responses in standard solutions were tested for lead, cadmium, and zinc (see Fig. 7.5). The results obtained show well-defined and single peaks for all of the metals. Sharper peaks were obtained for lead and cadmium compared to zinc. Detection limits of 23.1, 2.2, and 600 pgL-1 were estimated for lead, cadmium, and zinc, respectively, based on the signal-to-noise characteristics of these data (S/N = 3). The reproducibility of the Bi-GECE was also tested and found to be 2.99%, 1.56%, and 2.19% for lead, cadmium, and zinc, respectively. The difference in peak shapes (sharper for lead and cadmium) and in detection limits of these heavy metals can be explained by the binary and multi-component fusing alloys formation of lead and cadmium with bismuth [40]. According to these results, it was deduced that zinc competes with bismuth for the surface site rather than involving an alloy formation with this metal. 

The aluminum-based alloys such as 1100, 3300, 5052, 6053, Alclad 3300, Alclad 1017-T and Alclad 20-24-T are highly resistant to most natural environments alloys of thickness <0.076 mm should not be used. Lead and bismuth added to alloys 2021 and 6262 improve chip breakage and other machining characteristics. 

In conclusion, we note that deposition of submono- and monolayers of adatoms is the most controllable and reliably predictable method of obtaining metallic nanodimension compositions. At least two or three kinds of adatoms can be deposited in a strictly layer-by-layer fashion on single-crystal substrates [217], and mixed adlayers can also be obtained. The combined deposition of adatoms and phase deposits of metals [217] is even more promising. Among the metals, HTSC components such as lead, thallium, bismuth, and copper rank among the most thoroughly studied adatomic systems. Electrodeposition methods are also applied to the technological preparation of conventional superconductors based on Nb-Sn alloys [218]. 

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