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241.
Jon C. Van Loon 《Trends in analytical chemistry : TRAC》1984,3(10):272-275
This is the first of two papers to demonstrate the present status of the sophisticated analytical chemistry of the precious metals. In the present paper the methods of sample pretreatment will be surveyed. The determination methods will be covered in the next issue. 相似文献
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Phenyl sulphenyl chloride is a γ-selective electrophile in its reaction with O-silylated dienolates. 相似文献
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Jon Aaronson 《Israel Journal of Mathematics》1981,38(3):182-188
We generalise W. Feller’s limit theorem for (independent) random variables with infinite moments. 相似文献
247.
Stepan Boitsov Jon Songstad Karl W. Trnroos 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(8):o528-o532
The molecular structures of the three title nitro‐substituted phenylacetonitriles, C8H6N2O2, at 123 K show that the molecules are linked together very differently. In the 2‐ and 4‐nitro compounds, there are both O?H and Ncyano?H interactions, whereas the crystal lattice of the 3‐nitro compound is essentially built up by O?H interactions. The O atoms seem to prefer the aromatic H atoms, while the cyano N atoms prefer the methylene H atoms. The phenyl–nitro torsion angles are ?19.83 (13), ?5.69 (12) and ?2.88 (12)°, while the phenyl–cyanomethyl torsion angles are ?62.27 (12), ?147.99 (9) and ?16.75 (14)° in the 2‐, 3‐ and 4‐NO2‐substituted compounds, respectively. 相似文献
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Jon R. Appel Jaime Buencamino Richard A. Houghten Clemencia Pinilla 《Molecular diversity》1996,2(1-2):29-34
Summary Extensive mapping studies for seven antigen-antibody interactions have been carried out using both individual analogs and peptide libraries. With competitive ELISA, these studies have revealed that monoclonal antibodies exhibit a broad range of specificities, from antibodies that recognize only conservative substitutions for 1–2 positions of the antigenic determinant, to antibodies that recognize sequences that are completely unrelated to the parent antigen with comparable affinities. Synthetic combinatorial libraries, containing millions of peptide sequences, permit a more systematic and rapid evaluation of the extent of multiple-binding specificities of monoclonal antibodies than individual analogs. The peptide libraries used here comprise mixtures of compounds having specifically defined positions and mixture positions. The same diversity of sequences in different formats, which differ by the numbers of positions singularly defined and different locations defined within the sequence, can be examined. Comparison of the screening results, selection criteria of the most active mixtures, and different approaches used for the deconvolution of active individual compounds are discussed. Synthetic combinatorial libraries greatly facilitate the understanding of antigen-antibody interactions at the amino acid level and will assist in the development of improved immunodiagnostics. 相似文献