Benedict metal

Various alloys of nickel and copper are of great industrial importance. The two metals mix in all proportions, the nickel reducing the conductivity and increasing the hardness of the copper. The alloys are variously known as cupro-nickel, nickel bronze, and nickel brass, whilst certain of them have special names such as monel metal, Benedict metal, nickel or German silver, etc. 

Benedict metal is manufactured in the U.S.A., their Government specification for the alloy being ... 

The use of centrifuges for isotope enrichment was suggested by Lindemann and Aston as early as 1919, but success required the development of vacuum centrifuges in the late 1930s. The rotors in such devices are suspended in vacuum chambers and gas is introduced and withdrawn through metal capillaries. Introductory discussions have been given by London (1961) and Benedict et al. (1981). 

Carbohydrates such as aldoses that undergo oxidation with metal ions are referred to as reducing sugars. Both copper(II) ions and silver ions are capable of oxidizing aldoses. Oxidation by copper(II) ions is the basis for Fehling s test and Benedict s test, whereas oxidation by silver ions is the key to Tollen s test. (Note These tests work for any sugar with a hemiacetal, but they don t work on acetals or ketals.)... 

CONTENTS Preface. George W. Gokel. Cryptophanes Receptors for Tetrahedral Molecules, Andre Collett, Jean-Pierre Dutasta and Benedict Lozach. Inclusion Polymerization in Steroidal Canal Complexes, Kiichi Takemoto, Mikiji Miyata. Functionalized Tetraazamacrocycles Ligands with Many Aspects, Thomas A. Kaden. Calixarenes as the Third Supramolecular Host, Seiji Shinkai, Kyushu University, Japan. Fluorescent Chemosensors for Metal and Non-Metal Ions in Aqueous Solutions Based on the Chief Paradigm, Anthony W. Czamik. Index. 

Potassium azide was claimed to be first prepd in 1898 by Dennis Benedict (Ref lb) and in the same year by Curtius Rissom (Ref 2), both by methods involving evapn of a soln of KOH neutralized with a slight excess of hydrazoic acid, HN3. This same method of prepn was described in 1894 by Dennis (Ref la). Browne Houlehan (Ref 3) obtd KNS by reactg metallic K with NH4N3 in liq NHj. Other methods of prepn are described by Hoth Pyl (Ref 16), Moldenhauer MiSttig (Ref 17), Wattenburg(Ref 17a), Franklin (Ref 19), Audrieth et al (Refs 21,... 

CBCL96] V. H. Crespi, L. X. Benedict, M. L. Cohen, and S. G. Louie, Prediction of a pure-carbon covalent metal, Journal of Physics Review, Series B 53 (1996) R13303-R13305. 

The azides of the alkaline earths were made by T. Curtius and J. Rissom by dissolving the oxides or hydroxides in dil. hydrazoic acid—say 2-8 per cent. The excess of alkaline earth can be removed by passing carbon dioxide into the boiling soln., and the filtrate cone, by evaporation. There remain colourless, rhombic needles of calcium azide, CaN6 and, according to L. M. Dennis and C. H. Benedict, spherical masses of minute crystals may be formed. The crystals are very hygroscopic and deliquescent. T. Curtius found that the salt does not explode by percussion, but it does so if rapidly heated on a metal plate, and it explodes at about 144°-156°... 

Fig. 8. Unit-cell volume of berkelium metal as a function of pressure. Adapted and reprinted with permission from the J. Phys. F Met. Phys. 14, U. Benedict, J. R. Peterson, R. G. Haire, and C. Dufour, 1984, The Institute of Physics, London (126).

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