Bismuth coatings

Wang, J., J. Lu, S. Hocevar, et al. 2000. Bismuth-coated carbon electrodes for anodic stripping voltammetry. Anal. Chem. 72 3218-3822. 

In similar experiments, Lin et al. [82] covalently attached glucose oxidase (GOx) to the exposed CNT end in a NEA and demonstrated that a hnear amper-ometric response can be obtained from 0.08 to 30 mM of glucose. Both the linear range and detection limit surpass other studies. The same group also demonstrated that the inlaid CNF NEA can be used for heavy metal ion detection. Trace Cd(II) and Pb(II) were deposited onto a bismuth-coated CNF NEA and then measured with stripping voltammetry. The detection limit was as low as 0.04 p.g/L (40 ppt) [83,84]. 

Daniele, S., Bragato, C. and Battistel, D. (2012) Bismuth-coated mesoporous platinum micro-electrodes as sensors for formic acid detection. Electroanalysis, 24, 759-766. 

Joseph Wang, J.L., Samo B. Hocevar, and Percio A. M. Farias, Bozidar Ogorevc, Bismuth-Coated Carbon Electrodes for Anodic Stripping Voltammetry. Analytical Chemistry, 2000. 72 p. 3218-3222. 

Wang J, Lu J, Hocevar SB, Ogorevc B (2001) Bismuth-coated screen-printed electrodes fm stripping voltammetric measurements of trace lead. Electroanalysis 13 13—16... 

Baldrianova L, Svancara I, Vlcek M, Economou A, Sotiropoulous S (2006) Effect of Bi(in) concentration on the stripping voltammetric response of in situ bismuth-coated carbmt paste and gold electrodes. Electrochim Acta 52 481-490... 

Some metals used as metallic coatings are considered nontoxic, such as aluminum, magnesium, iron, tin, indium, molybdenum, tungsten, titanium, tantalum, niobium, bismuth, and the precious metals such as gold, platinum, rhodium, and palladium. However, some of the most important poUutants are metallic contaminants of these metals. Metals that can be bioconcentrated to harmful levels, especially in predators at the top of the food chain, such as mercury, cadmium, and lead are especially problematic. Other metals such as silver, copper, nickel, zinc, and chromium in the hexavalent oxidation state are highly toxic to aquatic Hfe (37,57—60). 

The existence of bismuthine was first demonstrated by using a radioactive tracer, Bi (8). Acid treatment of a magnesium plate coated with Bi resulted in the hberation of a volatile radioactive compound. In subsequent experiments, magnesium bismuthide [12048-46-3], Mg Bi, was treated with acid the yield, however, was only one part of bismuthine for every 20,000 parts of bismuth dissolved. Attempts to prepare bismuthine by reduction of bismuth trichloride with a borohydride have not been particularly successful. Experimental quantities ate best prepared by disproportionation of either methylbismuthine [66172-95-0], CH Bi, or dimethylbismuthine [14381-45-4], C2H. Bi (7) ... 

Bismuth. Bismuth 2-ethyIhexanoate [72877-97-5] is an auxiliary drier that has been promoted for drying under adverse conditions. Like rare earths, in some coatings it is reported to give better results than zirconium at low temperature and high humidity. 

Antimony and Bismuth. In attempting to dissolve alloys of these metals in hot 72% perchloric ac, a coating was formed which was very sensitive and expl. The chem nature of the deposits was not ascertained (Ref 9)... 

Metal oxide electrodes are also of the second type. A well known example is a rod of antimony coated with Sb203 (or bismuth with Bi203), which can function as a pH electrode33 ... 

Nicholson, D. G. el al., J. Amer. Chem. Soc., 1935, 57, 817 Attempts to dissolve bismuth and its alloys in hot perchloric acid carry a very high risk of explosion. At 110°C a dark brown coating is formed, and if left in contact with the acid (hot or cold), explosion occurs sooner or later. The same is true of antimony and its tervalent compounds. 

Nevertheless the heat capacity of a carbon resistor was not so low as that of crystalline materials used later. More important, carbon resistors had an excess noise which limited the bolometer performance. In 1961, Low [61] proposed a bolometer which used a heavily doped Ge thermometer with much improved characteristics. This type of bolometer was rapidly applied to infrared astronomy as well also to laboratory spectroscopy. A further step in the development of bolometers came with improvements in the absorber. In the early superconducting bolometer built by Andrews et al. (1942) [62], the absorber was a blackened metal foil glued to the 7A thermometer. Low s original bolometer [61] was coated with black paint and Coron et al. [63] used a metal foil as substrate for the black-painted absorber. A definite improvement is due to J. Clarke, G. I. Hoffer, P. L. Richards [64] who used a thin low heat capacity dielectric substrate for the metal foil and used a bismuth film absorber instead of the black paint. 

The answer is d. (Hardman, pp 909-910.) It is now recognized that infection with fi pylon is a major etiologic factor in peptic ulcer disease. Bismuth salts are bactericidal for many organisms but especially for spirochetes. Colloidal bismuth salts such as bismuth subsalicylate also have a coating or cytoprotective action. Antimicrobials and GI antisecretory drugs are also used in combination with bismuth compounds. 

Bismuth is the fifth element in the nitrogen group, and its properties are the most metal-like of the five. Elemental bismuth is a heavy, brittle, hard metal that can be polished to a bright gray-white coat with a pinkish hue. It is not found in this state very often because it is more likely to be combined with other metals and minerals, such as tin, lead, iron and cadmium. These are mixtures with low melting points, making them useful in fire-detection devices. 

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