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221.
Heineman W. R. Seliskar C. J. Richardson J. N. 《Russian Journal of Electrochemistry》2003,39(8):884-893
A thin-film spectroelectrochemical sensor design employing three modes of selectivity is described. Selectivity is achieved through (1) partitioning of the analyte into a chemically selective film, (2) electrochemical cycling of the analyte over a given potential window, and (3) absorbance of one of the redox states of the analyte at the chosen analytical wavelength. Optimization of the sensor is described with respect to both improved selectivity and sensitivity, as well as its response to a number of different chemical species. Lastly, application of the sensor for determination of ferrocyanide, Fe(CN)4-
6, in both radioactive waste simulant and actual waste storage tank contents is given. 相似文献
222.
The application of immunoaffinity techniques to subcellular fractionation is reviewed and the basic principles underlying
the various methods that have been successfully employed, identified. The requirement for organelle-specific antigens and
high-avidity antibodies is discussed, as is the widespread use of indirect immunoadsorbents. Approaches for the optimization
of immunoaffinity-based subcellular fractionation are suggested. 相似文献
223.
Bender JL Corbin PS Fraser CL Metcalf DH Richardson FS Thomas EL Urbas AM 《Journal of the American Chemical Society》2002,124(29):8526-8527
The synthesis of a series of polymeric Eu(III) complexes with polyester ligands, along with supporting emission spectra, luminescence lifetimes, and, for a Eu block copolymer film, atomic force microscopy (AFM) data, is presented. Dibenzoylmethane was derivatized with a hydroxyl initiator site (dbmOH, 1) for tin octoate catalyzed ring opening polymerization of dl-lactide. The resulting poly(lactic acid) macroligand, dbmPLA (2), was combined with EuCl3 to generate Eu(dbmPLA)3 (3). Chelation of both dbmPLA and a polycaprolactone-functionalized bipyridine ligand (bpyPCL2) led to the Eu(III)-centered heteroarm star Eu(dbmPLA)3(bpyPCL2) (4). Unpolarized emission spectra and luminescence lifetimes were recorded for the Eu polymers in CH2Cl2 and for Eu(dbmPLA)3, as a film. Solution data for Eu(dbm)3 and Eu(dbm)3(bpy) were collected for comparison. For Eu tris(dbm) complexes, data were fit to a double exponential decay, indicating the presence of multiple species. Relative amounts of the longer lifetime component increase in the series Eu(dbm)3 solutions to Eu(dbmPLA)3 solutions to Eu(dbmPLA)3 films, perhaps suggesting benefits of the "polymer shell effect" and the diminishment of aquo adducts known to shorten lifetimes. As with the nonpolymeric analogue, data for Eu(dbmPLA)3(bpyPCL2) fit to a single-exponential decay. The sharpness of the feature at 579.7 nm, attributable to the 5D0 --> 7F0 transition in the emission spectrum of 4, lends further support for a homogeneous sample. AFM studies of "as cast" thin films of 4 reveal a lamellar structure with a 17.5 nm repeat. These microstructures, inferred to contain Eu luminophores at the glassy PLA-crystalline PCL domain interfaces, are modified by thermal treatment. 相似文献
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F. Simon A. Simon O. Fischer R. Glauner L. Ehling H. Kamerlingh Onnes I. H. Mathews Zeit G. Oddo H. Menzel E. Fromm A. Friedrich L. Schmid B. Becker Zeit E. Beckmann C. Platzmann J. F. Durand E. Rougé F. A. Henglein H. L. Richardson P. W. Robertson W. Plotnikow R. E. Hall W. D. Harkins M. D. Drapier 《Analytical and bioanalytical chemistry》1928,74(9):348-356
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