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111.
Sabine Hossenfelder 《Foundations of Physics》2011,41(9):1521-1531
We propose to experimentally test non-deterministic time evolution in quantum mechanics by consecutive measurements of non-commuting
observables on the same prepared state. While in the standard theory the measurement outcomes are uncorrelated, in a super-deterministic
hidden variables theory the measurements would be correlated. We estimate that for macroscopic experiments the correlation
time is too short to have been noticed yet, but that it may be possible with a suitably designed microscopic experiment to
reach a parameter range where one would expect a super-deterministic modification of quantum mechanics to become relevant. 相似文献
112.
Reineri F Bouguet-Bonnet S Canet D 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2011,210(1):107-112
When a hydrogenation reaction is carried out with gaseous hydrogen enriched in its para- isomer in the earth magnetic field (prior to adiabatic insertion of the sample in the NMR magnet), enhanced proton longitudinal order (represented by 2I(z)(A)I(z)(B)) is created but also difference of enhanced polarizations (I(z)(A)-I(z)(B)). In a first part, it is shown theoretically and experimentally that the longitudinal relaxation time of this polarization difference is roughly twice the ones of individual polarizations. The second part is devoted to a pulse sequence designed for transforming this difference into net hyperpolarization. The evolution of this global hyperpolarization is studied experimentally in a third part and it is observed that a fraction of hyperpolarization possesses an effective longitudinal relaxation time similar to the one of the initial polarization difference. Those experimental results are interpreted by numerical calculations based on Solomon-type equations including the longitudinal order and possibly dipolar-csa cross correlation rates. 相似文献
113.
114.
Manfred Gerken Sabine Blank Cenek Kolar Peter Hermentin 《Journal of carbohydrate chemistry》2013,32(2):247-254
Abstract 10-O-(R/S)Tetrahydropyranosyl-β-rhodomycinone (5a,b) was prepared via 7,9-O-phenylboronyl-β-rhodomycinone (3) from β-rhodomycinone (1). Glycosidation of 5a,b with 3,4-di-O-acetyl-1,5-anhydro-2,6-dideoxy-L-arabino-hex-1-enitol (3,4-di-O-acetyl-L-rhamnal) (6) and 3,4-di-O-acetyl-1,5-anhydro-2,6-dideoxy-L-lyxo-hex-1-enitol (3,4-di-O-acetyl-L-fucal) (7) using N-iodosuccinimide gave the corresponding 7-O-glycosyl-β-rhodomycinones 8a,b, 9a,b and 10a,b, 11a,b. After cleavage of the THP-ether and O-deacetylation 7-O-(2,6-dideoxy-2-iodo-α-L-manno-hexopyranosyl)-β-rhodomycinone (14) and 7-O-(2,6-dideoxy-2-iodo-α-L-talo-hexopyranosyl)-β-rhodomycinone (16) were obtained. 相似文献
115.
Inside Cover: Selective Protein Hyperpolarization in Cell Lysates Using Targeted Dynamic Nuclear Polarization (Angew. Chem. Int. Ed. 36/2016)
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116.
117.
Per J. Garegg Petra Ossowski Sabine Köpper Joachim Thiem 《Journal of carbohydrate chemistry》2013,32(1):59-65
The use of silver zeolite as a promoter for the preparation of β-linked 2-deoxygtycosides and disaccharides of biological relevance has been explored. Starting from benzoylated glycosyl bromides, the total yield of glycosides varies from 54 to 84% and the α:β ratio from 0.25 to 1.18. 相似文献
118.
119.
Matthias Westerhausen Sabine Weinrich Manfred Oßberger Norbert W. Mitzel 《无机化学与普通化学杂志》2003,629(4):575-577
The reaction of calcium‐bis[bis(trimethylsilyl)amide] with two equivalents triethylgallium yields nearly quantitatively the addition product. In the solid state the calcium atoms are coordinated by two nitrogen atoms and two ethyl groups, whereas in solution all ethyl substituents are magnetically equivalent even at low temperatures. The Ca‐C‐Ga two‐electron three‐center bonds show mean Ca‐N and Ca‐C distances of 243 and 268 pm, respectively. 相似文献
120.
Jürgen Einax Bernd Machelett Sabine Geiß Klaus Danzer 《Fresenius' Journal of Analytical Chemistry》1992,342(4-5):267-272
Summary The characterization of the heavy metal contents of a soil area is carried out by narrow screening sampling and subsequent analysis. It is possible by means of the univariate variance analysis to detect significant alterations within the tested area. The position and extent of multivariate changes of the features can be characterized more exactly with the help of multivariate statistical methods such as the combination of cluster and discriminant analytical methods or the principal component analysis. The maximum possible distance between two sampling points is determined by calculation of the autocorrelation function of the features. The number of soil samples, which is necessary for precisely determining the heavy metal contents of the investigated area, can be derived therefrom. With the help of the multivariate autocorrelation function the distance for the representative sampling of the multivariate loads by heavy metals can be described. 相似文献