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131.
The comparison of proteins separated on 2DE is difficult due to gel-to-gel variability. Here, a method named comparative fluorescence gel electrophoresis (CoFGE) is presented, which allows the generation of an artificial protein grid in parallel to the separation of an analytical sample on the same gel. Different fluorescent stains are used to distinguish sample and marker on the gel. The technology combines elements of 1DE and 2DE. Special gel combs with V-shaped wells are placed in a stacking gel above the pI strip. Proteins separated on the pI strip are electrophoresed at the same time as marker proteins (commercially available purified protein of different molecular weight) placed in V-wells. In that way, grids providing approximately 100 nodes as landmarks for the determination of protein spot coordinates are generated. Data analysis is possible with commercial 2DE software capable of warping. The method improves comparability of 2DE protein gels, because they are generated in combination with regular in-gel anchor points formed by protein standards. This was shown here for two comparative experiments with three gels each using Escherichia coli lysate. For a set of 47 well-defined samples spots, the deviation of the coordinates was improved from 7% to less than 1% applying warping using the marker grid. Conclusively, as long as the same protein markers, the same size of pI-strips and the same technology are used, gel matching is reproducibly possible. This is an important advancement for projects involving comparison of 2DE-gels produced over several years and in different laboratories. 相似文献
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Mar'yana Lukachuk Birgit Heying Ute Ch. Rodewald Rainer Pttgen 《Heteroatom Chemistry》2005,16(5):364-368
The ternary indides Sc5 Ni2 In4 and Sc5 Rh2 In4 were synthesized by arc‐melting of the elements and subsequent annealing. A structural investigation by X‐ray powder and single crystal diffraction revealed: Lu5 Ni2 In4 type, Pbam, a = 1716.3(2), b = 755.1(1), c = 335.22(5) pm, wR2 = 0.0721, 844 F2 values for Sc5 Ni2 In4, and a = 1754.3(3), b = 765.0(1), c = 332.97(6) pm, wR2 = 0.0363, 1107 F2 values for Sc5 Rh2 In4 with 36 variables per refinement. Both structures can be described as intergrowths of distorted AlB2‐ and CsCl‐related slabs, where the transition metal (T) atoms have a trigonal prismatic and the indium atoms a distorted square prismatic coordination. The shortest interatomic distances occur for Sc T and T In. The crystal chemistry and chemical bonding in these intermetallics are briefly discussed. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:364–368, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20106 相似文献
134.
Olaf Elsholz Carsten Frank Birgit Matyschok Frank Steiner Oliver Wurl Burkhard Stachel Heinrich Reincke Manfred Schulze Ralf Ebinghaus Maximilian Hempel 《Analytical and bioanalytical chemistry》2000,366(2):196-199
A monitor is described which provides the on-line determination of mercury in river water at concentrations from 20 to 1000 ng/L. The measurement includes an on-line digestion with Br–/BrO3 – and UV-radiation. Each determination is controlled by an on-line addition of 50 and 100 ng/L mercury carried out by pre-dilution of a 500 and 1000 ng/L stock solution using sequential injection analysis (SIA). One cycle of analysis takes 20 min and results in nine signals. A five days stand-alone operation has been performed successfully. Details are also published at web page: “http/www.rzbd.fh-hamburg.de/¶~prmercol” 相似文献
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A Navier-Stokes solver is applied to assess the effect of wall catalysis on the surface heat flux of hypersonic vehicles. The different catalytic boundary conditions are shortly discussed and results for a type IV interaction on a cylinder are presented and compared to experimental measurements. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Kuniyil Prabhakaran Birgit Schwenzer Steven P. DenBaars 《Applied Surface Science》2007,253(10):4773-4776
Nanoparticles of gallium nitride, synthesized by a low-temperature reaction between triethyl gallium and ammonia, were introduced onto silicon wafers containing a thin layer of chemically prepared silicon dioxide. At room temperature, the nanoparticles form unstructured agglomerates on the surface. However, upon annealing the samples beyond the decomposition temperature of the silicon dioxide layer, the gallium nitride particles self-organize to form triangular structures. The pattern formation is attributed to the domain separation associated with the (1 × 1)-(7 × 7) surface phase transformation followed by selective incorporation of the nanoparticles. 相似文献