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51.
To apply correlation liquid chromatography in practice, a reliable, accurate and simple injection system is essential. The injection system described is suitable. The system is tested thoroughly for different sample concentrations. The effects of possible non-idealities and incorrect working conditions are studied. The resulting disturbances are listed, so that inappropriate operating conditions can be traced and eliminated. To demonstrate the performance of the system, a standard mixture of polynuclear aromatic hydrocarbons is analysed and the results are compared with those obtained by conventional chromatography. The injection system and some special software greatly facilitates the practical use of correlation chromatography. 相似文献
52.
Modeling studies were performed on known inhibitors of the quadruple mutant Plasmodium falciparum dihydrofolate reductase (DHFR). GOLD was used to dock 32 pyrimethamine derivatives into the active site of DHFR obtained
from the x-ray crystal structure 1J3K.pdb. Several scoring functions were evaluated and the Molegro Protein-Ligand Interaction
Score was determined to have one of the best correlation to experimental pK
i
. In conjunction with Protein-Ligand Interaction scores, predicted binding modes and key protein-ligand interactions were
evaluated and analyzed in order to develop criteria for selecting compounds having a greater chance of activity versus resistant
strains of Plasmodium falciparum. This methodology will be used in future studies for selection of compounds for focused screening libraries. 相似文献
53.
Given a spacelike foliation of a spacetime and a marginally outer trapped surface S on some initial leaf, we prove that under a suitable stability condition S is contained in "horizon" i.e., a smooth 3-surface foliated by marginally outer trapped slices which lie in the leaves of the given foliation. We also show that under rather weak energy conditions this horizon must be either achronal or spacelike everywhere. Furthermore, we discuss the relation between "bounding" and "stability" properties of marginally outer trapped surfaces. 相似文献
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H. Weber B. Neumann A. Aupperle E. Jaboulay G. Mars L. L. de Koninck E. v. Winiwarter M. Trembour O. Bauer E. Deiss R. Amberg C. M. Johnson F. Wüst A. Stadeler F. Heinrich K. Roger H. Augustin P. Brès Th. C. Watters W. A. Koenig J. R. Cain und Wm. Brady 《Fresenius' Journal of Analytical Chemistry》1916,55(11):537-545
Ohne Zusammenfassung 相似文献
58.
Roux P Iturbe I Nicolas B Virieux J Mars JI 《The Journal of the Acoustical Society of America》2011,130(3):1232-1241
Acoustic tomography in a shallow ultrasonic waveguide is demonstrated at the laboratory scale between two source-receiver arrays. At a 1/1,000 scale, the waveguide represents a 1.1-km-long, 52-m-deep ocean acoustic channel in the kilohertz frequency range. Two coplanar arrays record the transfer matrix in the time domain of the waveguide between each pair of source-receiver transducers. A time-domain, double-beamforming algorithm is simultaneously performed on the source and receiver arrays that projects the multi-reflected acoustic echoes into an equivalent set of eigenrays, which are characterized by their travel times and their launch and arrival angles. Travel-time differences are measured for each eigenray every 0.1 s when a thermal plume is generated at a given location in the waveguide. Travel-time tomography inversion is then performed using two forward models based either on ray theory or on the diffraction-based sensitivity kernel. The spatially resolved range and depth inversion data confirm the feasibility of acoustic tomography in shallow water. Comparisons are made between inversion results at 1 and 3 MHz with the inversion procedure using ray theory or the finite-frequency approach. The influence of surface fluctuations at the air-water interface is shown and discussed in the framework of shallow-water ocean tomography. 相似文献
59.
The Einstein–Straus model consists of a Schwarzschild spherical vacuole in a Friedman–Lemaître–Robertson–Walker (FLRW) dust spacetime (with or without $\Lambda $ Λ ). It constitutes the most widely accepted model to answer the question of the influence of large scale (cosmological) dynamics on local systems. The conclusion drawn by the model is that there is no influence from the cosmic background, since the spherical vacuole is static. Spherical generalizations to other interior matter models are commonly used in the construction of lumpy inhomogeneous cosmological models. On the other hand, the model has proven to be reluctant to admit non-spherical generalizations. In this review, we summarize the known uniqueness results for this model. These seem to indicate that the only reasonable and realistic non-spherical deformations of the Einstein–Straus model require perturbing the FLRW background. We review results about linear perturbations of the Einstein–Straus model, where the perturbations in the vacuole are assumed to be stationary and axially symmetric so as to describe regions (voids in particular) in which the matter has reached an equilibrium regime. 相似文献
60.
Marc Mars 《General Relativity and Gravitation》2013,45(11):2175-2221
Hypersurfaces of arbitrary causal character embedded in a spacetime are studied with the aim of extracting necessary and sufficient free data on the submanifold suitable for reconstructing the spacetime metric and its first derivative along the hypersurface. The constraint equations for hypersurfaces of arbitrary causal character are then computed explicitly in terms of this hypersurface data, thus providing a framework capable of unifying, and extending, the standard constraint equations in the spacelike and in the characteristic cases to the general situation. This may have interesting applications in well-posedness problems more general than those already treated in the literature. As a simple application of the constraint equations for general hypersurfaces, we derive the field equations for shells of matter when no restriction whatsoever on the causal character of the shell is imposed. 相似文献