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991.
Quantitative mapping of metal ions freely diffusing in solution is important across a diverse range of disciplines and is particularly significant for dissolution processes in batteries, metal corrosion, and electroplating/polishing of manufactured components. However, most current techniques are invasive, requiring sample extraction, insertion of an electrode, application of an electric potential or the inclusion of a molecular sensor. Thus, there is a need for techniques to visualize the distribution of metal ions non‐invasively, in situ, quantitatively, in three dimensions (3D) and in real time. Here we have used 1H magnetic resonance imaging (MRI) to make quantitative 3D maps showing evolution of the distribution of Cu2+ ions, not directly visible by MRI, during the electrodissolution of copper, with high sensitivity and spatial resolution. The images are sensitive to the speciation of copper, the depletion of dissolved O2 in the electrolyte and show the dissolution of Cu2+ ions is not uniform across the anode.  相似文献   
992.
A microwave-enhanced, palladium-catalyzed protocol for the alpha-arylation of a protected glycine in neat water is described. This reaction proceeds rapidly, under non-inert conditions, to afford a range of phenylglycine derivatives in moderate to good yields. Based on this alpha-arylation, a number of aryl L-methionine-SR-sulfoximine (MSO) analogues were prepared and evaluated for their Mycobacterium tuberculosis glutamine synthetase (TB-GS) inhibitory activity.  相似文献   
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A newly devised fuzzy metric for measuring the dissimilarity between two planar chromatographic profiles is proposed in this paper. It does not require an accurately assigned sample-feature matrix and can cope with slight imprecision of the positional information. This makes it very suitable for 1-D techniques which do not have a second spectroscopic dimension to aid variable assignment. The usefulness of this metric has been demonstrated on a large data set consisting of nearly 400 samples from Denaturing Gradient Gel Electrophoresis (DGGE) analysis of microbes on human skin. The pattern revealed by this dissimilarity metric was compared with the one represented by a sample-feature matrix and highly consistent results were obtained. Several pattern recognition techniques have been applied on the dissimilarity matrix based on this dissimilarity metric. According to rank analysis, within-individual variation is significantly less than between-individual variation, suggesting a unique individual microbial fingerprint. Principal Coordinates Analysis (PCO) suggests that there is a considerable separation between genders. These results suggest that there are specific microbial colonies characteristic of individuals.  相似文献   
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An epoxide derived from (-)-shikimic acid was attached to a solid support and used to synthesize over 5000 diverse small molecules. Key transformations include a Lewis acid-catalyzed epoxide opening with amines and an intramolecular Heck reaction with aryl iodides. Compounds derived from this pathway were printed onto small-molecule microarrays and screened for binding to proteins. Compounds that bound to Aurora A kinase were characterized using surface plasmon resonance.  相似文献   
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Appendix: A primer on heavy-tailed distributions   总被引:4,自引:0,他引:4  
Sigman  Karl 《Queueing Systems》1999,33(1-3):261-275
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