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Power, Henry

The electrical age was built on the discovery in the early 1830s, independently by Joseph Henry (1797-1878) in America and Michael Faraday (1791-1867) in England, of electromagnetic induction, which led directly to the invention of the dynamo to generate electricity from steam-powered rotation. It came to fruition on New Year s Eve, 1879, when Thomas Edison (1847-1931) in rural New Jersey, after systematic and exhaustive experiments, made the first successful incandescent lamp, employing a carbonised filament made from some thread taken from Mrs. Edison s sewing cabinet. The lamp burned undimmed for 40 h, watched anxiously by Edison and some of his numerous collaborators. This lamp was ideal for... [Pg.364]

Henry Campbell Locomotive of the 4-4-0 "American" 1886 Frank J. Sprague Electric-powered operations from... [Pg.725]

The first nonrigid, powered, manned airship is flown by its builder, French engineer Henri Giffard this marks the beginning of the practical airship. [Pg.1242]

R. P. Burns Alwyn G. Davies Lawrence B. Ebert J. Fenner Richard J. Lagow C. A. McAuliffe F. P. McCullough John A. Morrison Geoffrey A. Ozin William J. Power A. Rabenau Henry Selig Peter J. Smith G. Trageser... [Pg.445]

The condensation of nitro compounds and imines, the so-called aza-Henry or nitro-Mannich reaction, has recently emerged as a powerful tool for the enantioselective synthesis of 1,2-diamines through the intermediate /3-amino nitro compounds. The method is based on the addition of a nitronate ion (a-nitro carbanion), generated from nitroalkanes, to an imine. The addition of a nitronate ion to an imine is thermodynamically disfavored, so that the presence of a protic species or a Lewis acid is required, to activate the imine and/or to quench the adduct. The acidic medium is compatible with the existence of the nitronate anion, as acetic acid and nitromethane have comparable acidities. Moreover, the products are often unstable, either for the reversibility of the addition or for the possible /3-elimination of the nitro group, and the crude products are generally reduced, avoiding purification to give the desired 1,2-diamines. Hence, the nitronate ion is an equivalent of an a-amino carbanion. [Pg.16]

The nitroaldol reaction or Henry reaction is a powerful and highly versatile carbon-carbon bond-forming reaction, allowing a plethora of key molecular frameworks, such as p-hydroxynitroalkanes, 1,2-amino alcohols or a-hydroxy carboxylic acids to be synthesised in a straightforward manner. Therefore, the development of practical catalytic asymmetric versions of this reaction is still largely desirable. The first catalytic asymmetric nitroaldol reaction was reported in 1992, " but despite its long history, relatively few chiral ligands have... [Pg.316]

At different types of adsorption isotherms plotted for adsorption of donor particles on oxides (see section 1.5) expressions (1.112) - (1.115) provide the rise in and decrease in with the growth of partial pressure of gas P, the functions themselves being different. Thus, in case of applicability of the Henry isotherm at small P we have the function oi - exp const-P becoming a power function <7s P with the rise in P which is often observed in experiments [154, 155, 169]. [Pg.71]

Webster, Charles. Henry Power s experimental philosophy. Ambix 14, no. 3 (Oct 1967) 150-178. [Pg.280]

Amara N, Ratsimba B, Marie A, Wilhelm, Delmas Henri (2001) Crystallization of potash alum effect of power ultrasound. Ultrason Sonochem 8(3) 265-270... [Pg.269]

Power, Philip, see Haubrich, Scott Piilm, Melanie, see Tacke, Reinhold Ranaivonjatovo, Henri, see Escudie, Jean... [Pg.309]

The Michael addition of nitroalkanes to election-deficient alkenes provides a powerful synthetic tool in which it is perceived that the nitro group can be transformed into various functionalities. Various kinds of bases have been used for this transformation in homogeneous solutions, or, alternatively, some heterogeneous catalysts have been employed. In general, bases used in the Henry reaction are also effective for these additions (Scheme 4.18).133... [Pg.103]

The nitroaldol (Henry) reaction has been recognized as a powerful synthetic tool and has also been utilized in the construction of numerous natural products and other useful compounds. As shown in Scheme 1, we succeeded in realizing the first exam-... [Pg.106]

The Henry reaction of nitro sugars and sugar aldehydes is a powerful tool for the formation of C-glycosydic bonds. A recent example is the preparation of disaccharide precursor 60 stated in Scheme 21.45 It involves a Henry reaction of nitro sugar 58 and aldehyde 59 in acetonitrile in the presence of catalytic potassium fluoride, to give nitro alcohol 60, a precursor of the corresponding C-disaccharide. [Pg.180]

Henry, J. D. and Powers, J. E. AIChE Jl 16 (1970) 1055-1063. Experimental and theoretical investigation of continuous flow column crystallisation. [Pg.896]

In 1896, Antonio Henri Becquerel (1852-1908) made a new type of battery and used a carbon rod. Ludwig Mond and Carl Langer produced a gas-powered battery and called their system a fuel cell in 1889. In 1889, Ludwig Mond (1838-1909) and assistant Carl Langer described their experiments with a hydrogen-oxygen fuel cell that attained 6 A (ampere) per square foot at 0.73 V. Mond and Langer s cell used electrodes of thin, perforated platinum. [Pg.222]

With a monomode CO2 laser, delivering a constant power on any rotational line of either the 10.4 jtx or the 9.4 n band, Bordfe and Henry studied the shape of Lamb dip profiles in CO2 which became asymmetric when two rotational lines were allowed to oscillate simultaneously, since the gains are tightly coupled by rotational thermalization. [Pg.68]


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See also in sourсe #XX -- [ Pg.51 , Pg.60 , Pg.63 , Pg.73 , Pg.78 ]




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