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1.
Iain D. H. Oswald 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(8):1021-1022
A new crystalline form of αβ‐d ‐lactose prepared by oven drying a concentrated aqueous solution of d ‐lactose is a lesson in the power of observation and the rigorous analysis of powder samples. 相似文献
2.
Peter Oswald 《Applications of Mathematics》2017,62(5):433-457
Compared to conforming P1 finite elements, nonconforming P1 finite element discretizations are thought to be less sensitive to the appearance of distorted triangulations. E.g., optimal-order discrete H1 norm best approximation error estimates for H2 functions hold for arbitrary triangulations. However, the constants in similar estimates for the error of the Galerkin projection for second-order elliptic problems show a dependence on the maximum angle of all triangles in the triangulation. We demonstrate on an example of a special family of distorted triangulations that this dependence is essential, and due to the deterioration of the consistency error. We also provide examples of sequences of triangulations such that the nonconforming P1 Galerkin projections for a Poisson problem with polynomial solution do not converge or converge at arbitrarily low speed. The results complement analogous findings for conforming P1 finite elements. 相似文献
3.
4.
Dr. Dennis Kubiczek Heinz Raber Dr. Nicholas Bodenberger Thomas Oswald Melis Sahan Daniel Mayer Dr. Sebastian Wiese Prof. Dr. Steffen Stenger Prof. Dr. Tanja Weil Dr. Frank Rosenau 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(64):14536-14545
Textbook procedures require the use of individual aptamers enriched in SELEX libraries which are subsequently chemically synthesized after their biochemical characterization. Here we show that this reduction of the available sequence space of large libraries and thus the diversity of binding molecules reduces the labelling efficiency and fidelity of selected single aptamers towards different strains of the human pathogen Pseudomonas aeruginosa compared to a polyclonal aptamer library enriched by a whole-cell-SELEX involving fluorescent aptamers. The library outperformed single aptamers in reliable and specific targeting of different clinically relevant strains, allowed to inhibit virulence associated cellular functions and identification of bound cell surface targets by aptamer based affinity purification and mass spectrometry. The stunning ease of this FluCell-SELEX and the convincing performance of the P. aeruginosa specific library may pave the way towards generally new and efficient diagnostic techniques based on polyclonal aptamer libraries not only in clinical microbiology. 相似文献
5.
Extending upon Daubechies et al. (Constr. Approx. 20:399–463, 2004) and Runborg (Multiscale Methods in Science and Engineering, pp. 205–224, 2005), we provide the theoretical analysis of normal multi-scale transforms for curves with general linear predictor S, and a more flexible choice of normal directions. The main parameters influencing the asymptotic properties (convergence,
decay estimates for detail coefficients, smoothness of normal re-parametrization) of this transform are the smoothness of
the curve, the smoothness of S, and its order of exact polynomial reproduction. Our results give another indication why approximating S may not be the first choice in compression applications of normal multi-scale transforms. 相似文献
6.
Kakaba Madi Peter Nyabeze Oswald Gwavava Matome Sekiba Baojin Zhao 《Journal of Radioanalytical and Nuclear Chemistry》2014,301(2):351-363
Gamma ray measurements were carried out along two parallel lines close to each of the hot springs using a RS 125 spectrometer to find the concentration (ppm) of U, Th, and K at Polile Tshisa, Aliwal North, and Badfontein hot springs. The RS 125 spectrometer is auto-stabilized on the naturally occurring U, Th, and K, and provides concentrations (ppm) of the radioelements. The results show that the concentration of thorium is higher, and is below the world average hazardous threshold of 7.4 ppm. Thorium is related to the occurrence of monazite seen at the scanning electron microscope. Higher ratios of U/K are indicative of an increase of uranium relative to potassium. Binary diagrams (Th–U, K–U, and K–Th) do not show a clear best fit except at Polile Tshisa hot spring where thorium shows a quasi positive correlation to potassium. In general, it can be concluded that the concentrations of these three radioelements are quite low, acceptable for groundwater, and could be hazardous to the health of humans and animals if exposed to long time radiations. 相似文献
7.
Jan Remsa Miroslav Jelinek Tomáš Kocourek Ji?í Oswald Marian ?erňanský Michal Jelínek 《Applied Surface Science》2009,255(10):5292-5294
High quality, thick, highly oriented crystalline thin films of Yttrium Aluminum Garnet (Y3Al5O12) and Yttrium Aluminum Perovskite (YAlO3) doped with Erbium were prepared by pulsed laser deposition. Samples were created in vacuum or oxygen environment. Depositions were arranged at room temperature, or at high substrate temperatures ranging from 800 to 1100 °C. Amorphous layers were annealed by laser, or in oven (argon flow, temperatures in range from 1200 to 1400 °C). Fused silica and sapphire (0 0 0 1) were used as substrates. Properties of films were characterized by X-ray diffraction, atomic force microscopy, and by photoluminescence measurement. Size of crystalline grains was in the range 116-773 nm. Thickness of layers was up to 17 μm. 相似文献
8.
R. Reiche S. Oswald D. Hofman J. Thomas K. Wetzig 《Analytical and bioanalytical chemistry》1999,365(1-3):76-82
For further evaluation of photoemission properties of argon ion bombarded rhenium-silicon thin films pure element Re(21 nm)
/ Si(39 nm) / Re(21 nm) layer sandwiches were investigated on Si(111) substrates. TEM cross sectioning revealed abrupt interfaces
between the polycrystalline Re layers and the amorphous Si layer in the as-deposited sample. In XPS sputter depth profiling
the interfaces were severely broadened. This is not just a result of the finite electron escape depth together with atomic
mixing and preferential sputtering which was demonstrated with the dynamic Monte Carlo simulation program T-DYN, but mainly
caused by topographic effects and silicide formation. Factor analysis of XPS spectra results in two Re-Si principal components
which can be ascribed to silicide bonding. Accordingly the valence band changes are caused by different bonding configurations.
Bombardment-induced silicide formation is proved by TEM investigations of a selected cross-sectioned sandwich. Due to preferential
bombardment-induced effects Re2Si is formed at the Re/Si interfaces in contrast to the ReSi2 growth on thermal heating. This is discussed in terms of the interface composition and the effective heat of formation (EHF)
model.
Received: 6 September 1998 / Revised: 17 December 1998 / Accepted: 31 January 1999 相似文献
9.
J. Nieto T. Oswald F. Blanco Joao B. P. Soares Benjamin Monrabal 《Journal of Polymer Science.Polymer Physics》2001,39(14):1616-1628
The effect of molecular weight and long‐chain branching on the crystallization analysis fractionation (CRYSTAF) of ethylene homopolymers was investigated. Several ethylene homopolymers were prepared with different molecular weights and levels of long‐chain branching to isolate these effects from the dominant effect of comonomer content on crystallizability measured by CRYSTAF. Molecular weight effects might be significant for samples with number‐average molecular weights below 5000, but this effect can be corrected if terminal methyl groups are taken into account. Long‐chain branching has only a very small effect on the CRYSTAF profile of the samples investigated in this study. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 1616–1628, 2001 相似文献
10.
The use of factor analysis for automatic interpretation of electron spectra needs in some cases a special data preprocessing. It was shown for x-ray photoelectron spectroscopy that in the case of non-conducting samples in addition to experimental methods (low energy electron flooding) a shift of the measured spectra with respect to a reference peak was useful. Thus, the residual energy shift due to sample charging, especially if the surface conductivity changes during measurement, could be removed. Several shift methods and the influence of different reference peaks were discussed. 相似文献