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The electrochemical phase isolation (EPI) is described as a preparation method for determining specific precipitations in solid materials in microamounts and microdimensions. Fundamental criteria are examined as a function of the main parameter (polarization current) on the system Fe3C in a Fe-matrix. The influence of the electrolyte composition on the electrochemical behaviour of the matrix, on the one hand, and of the phase, on the other hand, are investigated and utilized. 相似文献
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Pei-Yu Gao W. Kunath H. Gleiter K. Weiss 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1989,12(1-4):119-121
The structural feathers of penta-twinned gold particles (size between 2 and 6 nm) generated by gas evaporation have been investigated by high resolution TEM. The structural characteristic of penta-twinned particles is different from that of quasi-crystals that the five coherent or incoherent twin boundaries separating the twin oriented segments do not join up along a common edge. The lattice parameter is reduced by 4–5% in comparison to that of bulk gold. The formation of the penta-twinned particles is proposed to occur by particle collision. The particles were observed to be crystalline at ambient temperature. 相似文献
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H. Geissler H.-P. Hennig D. Kunath I. Ebert V. Hopfe U. Steinike 《Crystal Research and Technology》1982,17(10):1259-1266
Infrared investigations demonstrate a chemical interaction of quartz in hydrogen atmosphere during mechanical activation: By means of the SiH stretching band the number of formed SiH-groups is estimated as a function of the period of activation. of activation. This number is more than one order of magnitude less than the total number of adsorbed molecules. 相似文献
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Sonnenschein H Kreher T Gründemann E Krüger RP Kunath A Zabel V 《The Journal of organic chemistry》1996,61(2):710-714
The first compounds of a new series of redox-active cyclophanes were prepared by dehydrocyclization of bridged indolizines of type 1. The bridged dipyridino-compounds 2a and 2b obtained by reaction of 2 mol of lithiated alpha-picolines with dihalides were used as starting materials. Subsequent treatment of 2a,b with 2 mol of alpha-bromo ketones gave quaternary pyridinium halides. Ring closure in an alkaline medium (Chichibabin reaction) yielded the starting material for the synthesis of the macrocycles. Oxidative C-C coupling gave the diastereomeric cyclophanes of type 3. In all cases one pair of the enantiomers was obtained in excess. CV-investigations have shown that the main products are reversible redox systems. To clarify their conformations, compounds 3c, 3d/1, and3d/2 were subjected to X-ray analysis. 相似文献
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Alexandre Chappard Dr. Craig Leighton Dr. Rebecca S. Saleeb Kiani Jeacock Dr. Sarah R. Ball Katie Morris Owen Kantelberg Dr. Ji-Eun Lee Dr. Elsa Zacco Prof. Dr. Annalisa Pastore Prof. Dr. Margaret Sunde Dr. David J. Clarke Dr. Patrick Downey Prof. Dr. Tilo Kunath Dr. Mathew H. Horrocks 《Angewandte Chemie (International ed. in English)》2023,62(15):e202216771
Protein misfolding and aggregation into oligomeric and fibrillar structures is a common feature of many neurogenerative disorders. Single-molecule techniques have enabled characterization of these lowly abundant, highly heterogeneous protein aggregates, previously inaccessible using ensemble averaging techniques. However, they usually rely on the use of recombinantly-expressed labeled protein, or on the addition of amyloid stains that are not protein-specific. To circumvent these challenges, we have made use of a high affinity antibody labeled with orthogonal fluorophores combined with fast-flow microfluidics and single-molecule confocal microscopy to specifically detect α-synuclein, the protein associated with Parkinson's disease. We used this approach to determine the number and size of α-synuclein aggregates down to picomolar concentrations in biologically relevant samples. 相似文献
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G. Kunath P. Losso S. Steuernagel H. Schneider C. Jger 《Solid state nuclear magnetic resonance》1992,1(5)
27Al NMR spectra of polycrystalline aluminium borate 9Al2O3 · 2B2O3 have been measured at 104, 130 and 156 MHz. The parameters of the quadrupole interaction and the isotropic chemical shifts have been obtained by fitting the CT/MAS pattern and consideration of the inner satellite transitions m = 3/2 ↔ 1/2 and m = −1/2 ↔ −3/2. The gain in spectral resolution concerned with the observation of the MAS lines of the inner satellites leads to complete separation of the signals of AlO6, AlO5 and AlO4 polyhedra. Also signals of structural groups of one and the same coordination number can be distinguished. Experimental and theoretical lineshape calculations are compared. 相似文献
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Strauch G Haendel D Maass I Mühle K Runge A 《Isotopes in environmental and health studies》2011,47(3):280-285
Comparative biochemical and isotope-chemical investigations of cosmopolitical plants open up ways of obtaining parameters from different parts of the Earth which are characterised by variations in the habitat due to different environments. As an Antarctic oasis, the Schirmacher Oasis disposes of adequate favourable ecological conditions for the growth of lower plants. In the present paper, results of isotope studies of lichens, mosses and algae of the Schirmacher Oasis are given and peculiarities of the habitats which influence the isotope contents of the plants are discussed. 相似文献
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Gerhard Strauch Dietmar Haendel Ingeborg Maaß Karl Mühle Annamarie Runge 《Isotopes in environmental and health studies》2013,49(3):280-285
Comparative biochemical and isotope-chemical investigations of cosmopolitical plants open up ways of obtaining parameters from different parts of the Earth which are characterised by variations in the habitat due to different environments. As an Antarctic oasis, the Schirmacher Oasis disposes of adequate favourable ecological conditions for the growth of lower plants. In the present paper, results of isotope studies of lichens, mosses and algae of the Schirmacher Oasis are given and peculiarities of the habitats which influence the isotope contents of the plants are discussed. 相似文献