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61.
We present the first results of a new search for a permanent electric dipole moment of the 199Hg atom using a UV laser. Our measurements give d(199Hg) = -(1.06+/-0.49+/-0.40)x10(-28)e cm. We interpret the result as an upper limit absolute value [d(199Hg)]<2.1x10(-28)e cm (95% C.L.), which sets new constraints on theta bar;(QCD), chromo-EDMs of the quarks, and CP violation in supersymmetric models. 相似文献
62.
Moldovan L Melinte S Bayot V Papadakis SJ De Poortere EP Shayegan M 《Physical review letters》2000,85(20):4369-4372
We report very low temperature ( T) thermopower and resistivity ( rho) measurements on variable-density, two-dimensional hole systems confined to GaAs quantum wells. As the hole density is lowered from 1.49x10(11) cm(-2) to 0.14x10(11) cm(-2), the system crosses from an insulating ( drho / dT less, similar0) to a metallic regime ( drho / dT>0) and finally displays insulating behavior ( drho / dT<0). Diffusion thermopower shows a striking sign reversal in a narrow range of density in the metallic regime, suggesting a qualitative change in the conduction or the scattering mechanism. 相似文献
63.
We formulate the conditions under which the dynamics of a continuously measured quantum system becomes indistinguishable from that of the corresponding classical system. In particular, we demonstrate that even in a classically chaotic system the quantum state vector conditioned by the measurement remains localized and, under these conditions, follows a trajectory characterized by the classical Lyapunov exponent. 相似文献
64.
Elisabeth Drexler O. Frhr v. Lupin D. Weihe und P. B. Jacobs 《Fresenius' Journal of Analytical Chemistry》1937,109(3-4):129-135
Ohne Zusammenfassung 相似文献
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Herminghaus S. Jacobs K. Seemann R. 《The European physical journal. E, Soft matter》2001,5(1):531-538
The European Physical Journal E - A simple and predictive model is put forward explaining the experimentally observed substantial shift of the glass transition temperature, T g, of sufficiently... 相似文献
68.
The influence of all effective two- and three-particle interactions appearing in second order of perturbation theory was investigated for the 5d-shell atoms Hf, Ta, W, Re, and Os. The radial parts of the effective operators were treated as free parameters which were determined by a least squares fit of calculated energy levels to the observed ones. An appreciable reduction of the mean deviation was achieved in all spectra considered. A test of the eigenvectors of the effective Hamiltonian was performed by a comparison of calculatedg J values andg J values, which were measured with high precision by radiofrequency spectroscopy. The agreement found is typically better than a few parts in 104. 相似文献
69.
Ellingson D Potts B Anderson P Burkhardt G Ellefson W Sullivan D Jacobs W Ragan R 《Journal of AOAC International》2010,93(6):1897-1904
An improved method for direct determination of available carbohydrates in low-level products has been developed and validated for a low-carbohydrate soy infant formula. The method involves modification of an existing direct determination method to improve specificity, accuracy, detection levels, and run times through a more extensive enzymatic digestion to capture all available (or potentially available) carbohydrates. The digestion hydrolyzes all common sugars, starch, and starch derivatives down to their monosaccharide components, glucose, fructose, and galactose, which are then quantitated by high-performance anion-exchange chromatography with photodiode array detection. Method validation consisted of specificity testing and 10 days of analyzing various spike levels of mixed sugars, maltodextrin, and corn starch. The overall RSD was 4.0% across all sample types, which contained within-day and day-to-day components of 3.6 and 3.4%, respectively. Overall average recovery was 99.4% (n = 10). Average recovery for individual spiked samples ranged from 94.1 to 106% (n = 10). It is expected that the method could be applied to a variety of low-carbohydrate foods and beverages. 相似文献
70.