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141.
Gregg Jaeger 《Foundations of Physics》2011,41(3):299-304
It has been claimed that the Principle of the Identity of Indiscernibles (PII) is incompatible with quantum mechanics, considered
as a complete theory. Van Fraassen has argued specifically that a conflict between the two arises due to the requirements
of Bose-Einstein statistics when imposed on two-particle quantum states. It is shown here that this apparent contradiction
of the PII with quantum mechanics can be removed by the introduction of a natural criterion of individuality. 相似文献
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A high organic content CE-MS/MS (HOCE-MS/MS) method was developed for the proteomic analysis of envelope proteins extracted from spinach leaves. Separation was performed in a 1-m long hydroxypropyl cellulose coated capillary, using 8% (v/v) formic acid in 70% (v/v) methanol and 22% water as the BGE. A flow-through microvial interface was used to couple the CE system with an Orbitrap Fusion Lumos mass spectrometer, and field-amplified sample stacking was used to improve the concentration sensitivity. Using this optimized method, 3579 peptides and 1141 proteins were identified using the Proteome Discoverer software with a 1% false discovery rate at the protein level. Relative to conventional aqueous CE, HOCE-MS did a better job of discovering hydrophobic peptides and provided more peptide and protein identifications. Relative to nano-LC-MS, it achieved comparable peptide and protein identification performance and detected peptides not identified by LC-MS: of the full set of peptides identified using the two techniques, 19% were identified only using HOCE-MS. It also outperformed nano-LC-MS with respect to the detection of low molecular weight peptides. 相似文献
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This article surveys and catalogs the geometric diagrams that survive from ancient Egypt. These diagrams are often overspecified and some contain inaccuracies in their construction. The diagrams accompany algorithmic texts and support the mathematical programme of their authors. The study concludes with a brief comparison with the diagram traditions of ancient Babylon, early India, and Greece. 相似文献
148.
Marquardsen T Hofmann M Hollander JG Loch CM Kiihne SR Engelke F Siegal G 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2006,182(1):55-65
NMR based ligand screening is becoming increasingly important for the very early stages of drug discovery. We have proposed a method that makes highly efficient use of a single sample of a scarce target, or one with poor or limited solubility, to screen an entire compound library. This comparative method is based on immobilizing the target for the screening procedure. In order to support the method, a dual cell, flow injection probe with a single receiver coil has been constructed. The flow injection probe has been mated to a single high performance pump and sample handling system to enable the automated analysis of large numbers of compound mixes for binding to the target. The probe, having an 8 mm 1H/2H dual tuned coil and triple axis gradients, is easily shimmed and yields NMR spectra of comparable quality to a standard 5 mm high-resolution probe. The lineshape in the presence of a solid support is identical to that in glass NMR tubes in a 5 mm probe. Control spectra of each cell are identical and well separated, while ligand binding in a complex mixture can be readily detected in 20-30 min, thus paving the way for use of the probe for actual drug discovery efforts. 相似文献
149.
We definitively show, using an explicit and broadly applicable model, that local phase noise that is capable of eliminating state coherence only in the infinite-time limit is capable of eliminating nonlocality in finite time in three two-level systems prepared in the Bell-nonlocal tripartite states of the generic entanglement class. 相似文献
150.
Gregg M. Schwarzwalder Carson D. Matier Gregory C. Fu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(11):3609-3612
Metal‐catalyzed enantioconvergent cross‐coupling reactions of alkyl electrophiles are emerging as a powerful tool in asymmetric synthesis. To date, high enantioselectivity has been limited to couplings of electrophiles that bear a directing group or a proximal p/π orbital. Herein, we demonstrate for the first time that enantioconvergent cross‐couplings can be achieved with electrophiles that lack such features; specifically, we establish that a chiral nickel catalyst can accomplish Negishi reactions of racemic α‐halosilanes with alkylzinc reagents with good enantioselectivity under simple and mild conditions, thereby providing access to enantioenriched organosilanes, an important class of target molecules. 相似文献