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131.
132.
Claudia Weber Svenja Morsbach Katharina Landfester 《Angewandte Chemie (International ed. in English)》2019,58(37):12787-12794
One of the biggest challenges in the field of nanomedicine is the adsorption of biomolecules on the nanomaterial upon contact with a biological medium. The interactions of the resulting protein corona are essential for their behavior in a biological system. Thus, it is now commonly accepted that understanding the formation and consequently understanding the influence of the protein corona on the biological response is crucial. However, the outcome of the protein corona characterization cannot easily be compared between different studies and techniques, since many different sample preparation procedures exist that are suitable for different materials or methods. Depending on the applied procedure, the nanomaterial–protein system will be altered in a certain way, so that it is necessary to consider the individual influence on the protein corona. Accordingly, the aim of this Minireview is to give an overview of the applied sample preparation methods for the analysis of the protein corona and to evaluate their influence on the outcome of the results especially with regard to the introduced terms “soft” and “hard protein corona”. Special focus will be placed on the comparison of the most commonly used techniques such as centrifugation, magnetic, and chromatographic separation. 相似文献
133.
Christina Kjær Dr. Henriette Lissau Nina Katharina Gravesen Salinas Andreas Østergaard Madsen Dr. Mark H. Stockett Freja E. Storm Thomas Holm Hansen Prof. Jens Ulrik Andersen Prof. Bo W. Laursen Prof. Kurt V. Mikkelsen Prof. Mogens Brøndsted Nielsen Prof. Steen Brøndsted Nielsen 《Chemphyschem》2019,20(4):533-537
Being alone or together makes a difference for the photophysics of dyes but for ionic dyes it is difficult to quantify the interactions due to solvent screening and nearby counter ions. Gas-phase luminescence experiments are desirable and now possible based on recent developments in mass spectrometry. Here we present results on tailor-made rhodamine homodimers where two dye cations are separated by methylene linkers, (CH2)n. In solution the fluorescence is almost identical to that from the monomer whereas the emission from bare cation dimers redshifts with decreasing n. In the absence of screening, the electric field from the charge on one dye is strong enough to polarize the other dye, both in the ground state and in the excited state. An electrostatic model based on symmetric dye responses (equal induced-dipole moments in ground state) captures the underlying physics and demonstrates interaction even at large distances. Our results have possible implications for gas-phase Förster Resonance Energy Transfer. 相似文献
134.
The configurational isomers of astaxanthin (3,3′-dihydroxy-β,β-carotene-4,4′-dione) from the flesh of salmon (Salmo salar and Oncorhynchus) caught at different places in Europe and Canada were isolated and analyzed as (?)-camphanic acid diesters by means of HPLC. The biological variation in the composition of the configurational isomers in seven fish was surprisingly similar: 78 to 85% of (3S, 3′S)-astaxanthin, 12 to 17% (3R, 3′R)-astaxanthin and 2 to 6% meso-astaxanthin. 相似文献
135.
Oliver Staller Christina Mitterbauer Katharina Mayr 《Central European Journal of Chemistry》2008,6(4):535-541
In this paper we report a method to determine tensile strengths and Young’s modulus of cubic biaxial textured metal tapes
used as substrate materials for coated conductors (CC). Simplicity, rapidity and reproducibility of the procedure are important
for the evaluation of continuous in-house productions. Our approach is based on the EN 10002-1 B tensile test method. A key
role for satisfactory results is the sample preparation of 100–250 μm thick tapes, which will be described in detail. Copper
(E-Cu57) can be successfully transformed to cubic biaxial textured substrates. Best results were achieved by annealing between
750°C and 850°C in reducing atmosphere. Best FWHM values for the ψ scan are 5.51° and for the ϕ scan are 4.5°. Pole figure
analysis verified the sharp {001} <100> texture of the tape. Vickers hardness measurements (HV 0.1) for the cold worked material
yielded values of 135 and for the annealed tape, values of 37. The ultimate tensile yield strength Rm of the textured substrate
is 150 MPa and thus significantly lower than that for the cold worked material (413 MPa). Cubic biaxial substrates could be
manufactured from Isotan CuNi44 (WM49) bars. Best results were achieved by annealing at 1200°C in reducing atmosphere. Pole
figure analysis verified the {001} <100> texture with other low intensity texture components. Vickers hardness measurements
(HV 0.1) for the cold worked material yielded values of 236 and for the annealed tape values of 92. The ultimate tensile yield
strength R
m of the textured substrate is 300 MPa and thus significantly lower than that for the cold worked material (723 MPa).
相似文献
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140.
Simone Dill Katharina Gibson Jochen Glaser Sonja Tragl H.‐Jürgen Meyer Prof. Dr. 《无机化学与普通化学杂志》2007,633(2):274-279
Synthesis and Structure of the Basic Alkaline Earth Nitrates Sr2(OH)3NO3 and Ba2(OH)3NO3 Sr2(OH)3NO3 and Ba2(OH)3NO3 were synthesized from mixtures of freshly prepared strontium or barium hydroxides and their corresponding nitrates in evacuated quartz glass ampoules at 420 °C and 360 °C, respectively. Single crystals of Sr2(OH)3NO3 were obtained in a solidified Sr(NO3)2 melt after subsequent heating and cooling cycles in air up to 600 °C. The crystal structure of the strontium compound was refined from single crystal and powder X‐ray data. Sr2(OH)3NO3 crystallizes hexagonally in the space group (No. 189) with Z = 1 and the lattice parameters a = 6.624(2) Å and c = 3.560(1) Å (single crystal data). The powder pattern of Ba2(OH)3NO3 was indexed isotypically to Sr2(OH)3NO3 with the lattice parameters a = 6.9260(1) Å and c = 3.8086(1) Å, and the crystal structure was refined from powder X‐ray data. Alkaline earth ions in the structures are surrounded trigonal‐prismatically by six hydroxide ions. These prisms are sharing their trigonal faces along [001] building up columns. These columns are connected in the ab‐plane by shared edges, and form hexagonal tunnels with the nitrate groups stacked inside. Infrared and thermoanalytical data of Sr2(OH)3NO3 are presented. 相似文献