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B. P. Nicolsky V. I. Paramonova A. Stock H. Th. St. Britton C. Naegeli A. Tyabji Soerensen Walbum Ringer J. M. Kolthoff L. V. Wilcox B. Cavanagh B. Diethelm F. Foerster T. Callan J. A. Russell Henderson C. Robinson O. L. Evenson R. H. Nagel D. T. Mc Cutchen J. A. Atanasiu A. I. Verculescu R. R. Ralston C. H. Fellows K. S. Wyatt H. Seltz D. S. Mc Kinney K. Masaki C. del Fresno E. Mairlot E. Jimeno J. Ibarz 《Analytical and bioanalytical chemistry》1932,90(7-8):281-287
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High-throughput methods have been employed to study the system Co(2+)/(H(2)O(3)PCH(2))(2)NCH(2)C(6)H(4)COOH/NaOH in detail. The use of the phosphonocarboxylic acid (H(2)O(3)PCH(2))(2)NCH(2)C(6)H(4)COOH has led to several new cobalt carboxyaryl phosphonates under hydrothermal conditions. In addition to the effect of the pH of the starting mixture, the influence of the counterions of the cobalt salts on the product formation was investigated. Thus, reaction trends as well as fields of formation could be identified. Four new compounds Co(2)[(O(3)PCH(2))(2)NCH(2)C(6)H(4)COOH].H(2)O (1), Co[(O(3)PCH(2))(OCH)NCH(2)C(6)H(4)COOH].H(2)O (2), Co[H(2)(O(3)PCH(2))(2)NCH(2)C(6)H(4)COOH] (3), and [Co(2)(O(3)PCH(2))(2)NCH(2)C(6)H(4)COOH].3.5H(2)O (4) were obtained, and compounds 1 and 2 could be isolated as single crystals suitable for single-crystal X-ray diffraction. The counterions of the cobalt salts have an influence on the structure of the resulting compounds. This is due to the effect on the initial pH as well as the possibility of the counterions to take part in redox reactions. Compounds 1 and 4 are formed under more basic conditions, and the phosphonic acid group is fully deprotonated. The structure of 1 is a rare example of the family of inorganic-organic hybrid materials with iminobis(methylphosphonic acid) units wherein the nitrogen coordinates to the metal center. Compound 2 is the result of an in situ oxidation of one of the P-C bonds; the organic building unit is stabilized by complexation of the cobalt ion. On the basis of spectroscopic, thermogravimetric, elemental chemical analysis, and EDX-analysis data, compound 3 has been characterized as Co[H(2)(O(3)PCH(2))(2)NCH(2)C(6)H(4)COOH] and compound 4 as [Co(2)(O(3)PCH(2))(2)NCH(2)C(6)H(4)COOH].3.5H(2)O. X-ray powder diffraction and IR-spectroscopic studies show that thermal treatment of 4 leads to the title compound 1. This transformation is accompanied by a change of color from pink to deep blue. 相似文献
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Kathleen Stock 《Acta Analytica》2005,20(4):24-31
In Art as Performance, David Davies identifies certain properties relevant to artistic appreciation of artworks that, he suggests, are naturally
construed as belonging to the artist’s creative performance rather than to any product of that performance (the “work-product”).
He further argues, against an anticipated opponent, that such properties cannot be excluded as irrelevant to artistic appreciation
in any principled way. I argue that the cited properties can be intelligibly construed as properties of the associated work-product,
whether or not they are relevant to artistic appreciation; but that some are not relevant to artistic appreciation. In doing
so, I offer a principle determining when a property of an artwork is relevant to artistic appreciation. I conclude that, on
its own, Davies’s argument offers no good grounds to abandon our practice of thinking of the artwork as the product of an
artist’s activity, rather than the activity itself. 相似文献
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K. Wienhard K. Bangert R. Stock H. Wolf 《Zeitschrift für Physik A Hadrons and Nuclei》1974,270(2):93-95
The 90° photoproton spectrum from12C has been measured with good energy resolution using bremsstrahlung with maximum energyEγ=31 MeV. A fragmentation of the giant dipole resonance in fine structures with a typical width of 150 to 300 keV is observed. 相似文献
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