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1.
The process ${? e}^{+}{? e}^{-}?ghtarrow {? W}^{+}{? W}^{-}?ghtarrow {? f}_{1}{?erline {? f}}_{2}{? f}_{3}{?erline {? f}}_{4}$ contains charges in the initial, intermediate and final stages. This gives a rich selection of possible QED interconnection effects. Coulomb interaction is the simplest of these, and can thus be used to explore consequences. We study a number of experimental observables, with emphasis on those related to the W momentum distribution. Second-order Coulomb effects are shown to be practically negligible. The limited LEP 2 statistics will not allow detailed tests, so any theory uncertainty will be reflected in the systematic error on the W mass. Currently the uncertainty from this source may be as high as 20 MeV.  相似文献   
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We derive explicit isomorphism formulas between weighted Dirichlet integrals for harmonic functions and boundary Dirichlet forms. Applications yield results on traces of Markov processes and convergence quasieverywhere of harmonic functions.  相似文献   
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Optically active C(2)-symmetric (1S,2S,4S,5S)-bicyclo[2.2.2]octane-2,5-diol ((+)-12; 98% ee) and several selectively protected optically active intermediates useful for synthetic transformations were synthesized via a 1,2-carbonyl transposition route starting from the easily available optically active (1R,4S,6S)-6-hydroxybicyclo[2.2.2]octan-2-one ((-)-2). The synthetic route also allowed the preparation of optically active (1S,4S)-bicyclo[2.2.2]octane-2,5-dione ((+)-14; 98% ee).  相似文献   
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A synthesis of (2S,3S,7S)-3,7-dimethylpentadecan-2-yl acetate (2) and propionate (3) is described. (2S)-2-Methyldecan-1-yl lithium (5) was reacted with (3S,4S)-3,4-dimethyl-γ-butyrolactone (6) to yield the ketoalcohol 19 which upon Huang-Minlon reduction furnished (2S,3S,7S)-3,7-dimethylpentadecan-2-ol (1). Acylations gave the esters 2 and 3. The (2S)-2-methyldecan-1-yl lithium was obtained via asymmetric synthesis. The chiral lactone 6 was obtained from (2S,3S)-trans-2,3-epoxybutane and dimethyl malonate.  相似文献   
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Clay particles with adsorbed asphaltenes, which are commonly found in produced water, have been used as seed particles during precipitation of calcium carbonate in order to determine whether such particles may influence the kinetics of precipitation. The results show that the presence of the adsorbed asphaltenes accelerates the precipitation, and there is also a significant difference between different types of adsorbed asphaltenes. The adsorption of asphaltenes at the seed surface leads to a significant increase in the interfacial tension between the seed surface and the aqueous solution, and calcium carbonate therefore precipitates at the seed surface in order to reduce this high interfacial tension.  相似文献   
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A new method for the synthesis of allyl aromatic compounds not involving any metal-containing reagent or catalyst has been developed. Arylamines substituted with a large number of different substituents were converted via diazotizative deamination with tert-butyl nitrite in allyl bromide and acetonitrile to the corresponding allyl aromatic compounds. The allylation reaction was found to be suitable for larger scale synthesis due to short reaction times, a nonextractive workup, and robustness toward moisture, air, and type of solvent.  相似文献   
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