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1.
A. Craig W. H. Jacobson A. Meyer N. Welwart A. Seuthe H. N. Marr B. S. Evans G. E. F. Lundell J. A. Scherrer E. Stelling F. J. Mück A. Kling A. Lassieur L. Bertiaux C. C. Bissett P. de Pauw J. Heslinga A. Bartsch R. E. Lee W. H. Fegeley F. H. Reichel und E. Saz 《Fresenius' Journal of Analytical Chemistry》1927,71(1-2):83-90
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2.
Tanskanen H Khriachtchev L Lundell J Räsänen M 《The Journal of chemical physics》2004,121(17):8291-8298
We investigate the formation mechanism of HXeCCXeH in a Xe matrix. Our experimental results show that the HXeCCXeH molecules are formed in the secondary reactions involving HXeCC radicals. The experimental data on the formation of HXeCCXeH is fully explained based on the model involving the HXeCC+Xe+H-->HXeCCXeH reaction. This reaction is the first case when a noble-gas hydride molecule is formed from another noble-gas molecule. In addition, we investigate the (12)C/(13)C isotope effect on the vibrational properties of organo-noble-gas hydrides (HKrCCH, HXeCCH, HXeCC, and HXeCCXeH) in noble-gas matrixes. The present experimental results and ab initio calculations on carbon isotope shifts of the vibrational modes support the previous assignments of these molecules. Upon (12)C to (13)C isotope substitution, we observed a pronounced effect on the H-Kr stretching mode of HKrCCH (downshift of 1.0-3.6 cm(-1), depending on the matrix site) and a small anomalous shift (+0.1 cm(-1)) of the H-Xe stretching mode of HXeCCH and HXeCCXeH. 相似文献
3.
Sharp peaks were observed in the IR spectra of allyl alcohol dimers in the νOH and τOH regions in low-temperature Ar and N2 matrices. In Ar a peak at 3587 cm?1 was found to increase in intensity upon annealing and decrease upon IR irradiation; it is concluded that this peak is due to an OH...π interaction (of a cyclic structure) present in part of the dimers. This is the first time such an interaction and photoprocess have been found for an alcohol in matrices. Also a faster photo-process was found. Confomer changes in the monomers accompany the photoprocess in allyl alcohol dimers. 相似文献
4.
A one dimensional, nonlinear, singular integral equation was recently shown to be equivalent to Suhl's dispersion equations for the Kondo-problem of a half-spin magnetic impurity in a finite magnetic field. We investigate this integral equation further analytically and numerically and obtain numerical solutions which we use for a calculation of transport coefficients. The normal part of the scattering potential of the magnetic impurity is included via ans-wave phase shift. The transport coefficients are universal functions of the ratiosT/T
K andB/B
K of the temperatureT and the zero magnetic field Kondo-temperatureT
K and of the magnetic inductionB and the Kondo magnetic inductionB
K. We find maxima in the electrical and thermal resistivities as functions ofT/T
K forBB
K. These are typical Kondo phenomena, and can be influenced by. Interference of and the phases of Kondo-scattering amplitudes leads to dramatic effects in the thermopower and the Hall coefficient.SFB 125The numerical part of this work was performed at the Institut für Festkörperforschung, Kernforschungsanlage Jülich, F.R. Germany 相似文献
5.
Patrick J. Whitham Dennis P. Strommen Sandra Lundell Lisa D. Lau Rene Rodriguez 《Plasma Chemistry and Plasma Processing》2014,34(4):755-766
The plasma enhanced chemical vapor depositions of germanium chalcogenide thin films from germanium tetrachloride, hydrogen sulfide and alkyl chalcogenides were studied to determine the viability of these reagents for thin film deposition. Hydrogen sulfide is a commonly used reagent for this technique and was used to determine optimal reaction conditions for thin film deposition. Germanium tetrachloride, alkylsulfides and alkylselenides were also employed because of their lower potential toxicities and higher availabilities compared to their more typical congeners: germane, hydrogen sulfide and hydrogen selenide in the formation of germanium chalcogenides. Alkylsulfides were found to be unsuitable for the deposition of germanium sulfides, however alkylselenide precursors were used successfully for the deposition of germanium selenides. The relative mass flow rates, reactor pressure, substrate temperature and plasma power density were studied for their effects on germanium chalcogenide deposition. These parameters affected the composition, deposition rate, film quality, and spectroscopic properties of the deposited films. 相似文献
6.
Allan Carlsson Karl Håkansson Mathias Kvick Fredrik Lundell L. Daniel Söderberg 《Experiments in fluids》2011,51(4):987-996
Steerable filters are concluded to be useful in order to determine the orientation of fibers captured in digital images. The
fiber orientation is a key variable in the study of flowing fiber suspensions. Here, digital image analysis based on a filter
within the class of steerable filters is evaluated for suitability of finding the position and orientation of fibers suspended
in flowing suspensions. In sharp images with small noise levels, the steerable filter succeeds in determining the orientation
of artificially generated fibers with well-defined angles. The influence of reduced image quality on the orientation has been
quantified. The effect of unsharpness and noise is studied and the results show that the error in orientation is less than
1° for moderate levels. Images from two flow cases, one laminar shear flow and one turbulent, are also analyzed. The fiber
orientation distribution is determined in the flow-vorticity plane. For the laminar case a comparison is made to a robust,
but computationally more expensive, method involving convolutions with an oriented elliptic filter. A good agreement is found
when comparing the resulting fiber orientation distributions obtained with the two methods. For the turbulent case, it is
demonstrated that correct results are obtained and that the method can handle overlapping fibers. 相似文献
7.
Andreas Lundell Joakim Westerlund Tapio Westerlund 《Journal of Global Optimization》2009,43(2-3):391-405
In this paper some transformation techniques, based on power transformations, are discussed. The techniques can be applied to solve optimization problems including signomial functions to global optimality. Signomial terms can always be convexified and underestimated using power transformations on the individual variables in the terms. However, often not all variables need to be transformed. A method for minimizing the number of original variables involved in the transformations is, therefore, presented. In order to illustrate how the given method can be integrated into the transformation framework, some mixed integer optimization problems including signomial functions are finally solved to global optimality using the given techniques. 相似文献
8.
E. Barnitzke D. Brunton J. A. Scherrer G. E. F. Lundell H. Gehle E. Hildebrandt und E. Schiller 《Fresenius' Journal of Analytical Chemistry》1933,94(7-8):257-259
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9.
10.
G. E. F. Lundell H. B. Knowles und Weber 《Fresenius' Journal of Analytical Chemistry》1926,68(7-8):306-309
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