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31.
The nonconforming Wilson's brick classically is restricted to regular hexahedral meshes. Lesaint and Zlamal[6] relaxed this constraint for the two-dimensional analonue of this element In this paper we extend their results to three dimensions and prove that and where u is the exact solution, u_h is the approximate solution and is the usual norm for the Sobolev space H~1(?). 相似文献
32.
Leufgen K Mutter M Vogel H Szymczak W;TOF-SIMS Study 《Journal of the American Chemical Society》2003,125(29):8911-8915
Structure and orientation of molecules are key properties of functionalized surfaces. Using time-of-flight secondary ion mass spectrometry (TOF-SIMS), here we investigate how to modulate these parameters upon the immobilization process varying the conditions of self-assembly. The molecule of interest, a template-assembled synthetic protein (TASP), consists of a central peptide ring with orthogonally arranged residues. Thioalkane chains allow the directed self-assembly of the molecule on a gold surface; four serine residues on the opposite side of the ring can be used as anchoring sites for various functional sensing molecules. The TASP conformation and its orientation in self-assembled monolayers (SAMs) play a central role for the accessibility of these serine residues. To study the influence of the self-assembly conditions, two series of samples were prepared. Pure TASP monolayers of different surface densities are compared to mixed TASP/alkanethiol monolayers prepared by sequential adsorption varying sequence and particular incubation times as well as by coadsorption modifying incubation times and TASP/alkanethiol mass ratios. Switching the TASP orientation from a state where the molecules are lying flat on the surface to an upright orientation turned out to be possible by inserting the TASP into a preformed alkanethiol monolayer of an appropriate surface density. This study demonstrates that TOF-SIMS is an excellent tool not only to investigate the surface composition, but also the molecular structure of functionalized surfaces. 相似文献
33.
Bound state solutions of d-dimensional Schrdinger equation with Eckart potential plus modified deformed Hylleraas potential 下载免费PDF全文
We study the d-dimensional Schrdinger equation for Eckart plus modified deformed Hylleraas potentials using the generalized parametric form of Nikiforov-Uvarov method.We obtain energy eigenvalues and the corresponding wave function expressed in terms of a Jacobi polynomial.We also discuss two special cases of this potential comprised of the Hulthen potential and the Rosen-Morse potential in three dimensions.Numerical results are also computed for the energy spectrum and the potentials. 相似文献
34.
E. Study 《Mathematische Annalen》1924,91(3-4):225-248
Ohne Zusammenfassung 相似文献
35.
E. Study 《Mathematische Annalen》1923,89(3-4):298-314
Ohne Zusammenfassung(Dritte Fortsetzung.) 相似文献
36.
Influence of arsenic,antimony and cobalt impurities on the cathodic process in zinc electrowinning 下载免费PDF全文
YU XiaoHua XIE Gang LI RongXing LI YongGang & LU Ying Faculty of Metallurgical Energy Engineering Kunming University of Science Technology Kunming China Technology Center of Yunnan Metallurgy Group Co. Kunming 《中国科学:化学》2010,(3)
By means of an electrochemical study,the influence of arsenic,antimony and cobalt on cathodic polarization in the zinc electrowinning process,the associated kinetic equations and parameters,and the polarization mechanism have been studied.The results show that the experimental values of the kinetic parameters are in accord with the theoretical values in the ZnSO4/H2SO4 solution with a single impurity is added.In contrast,the charge transfer coefficient α is smaller than the theoretical value in the ZnSO4/H2... 相似文献
37.
E. Study 《Mathematische Annalen》1924,91(1-2):82-118
Ohne Zusammenfassung4. Fortsetzung. 相似文献
38.
E. Study 《Mathematische Annalen》1906,63(2):239-245
Ohne Zusammenfassung 相似文献
39.
Lakatos A Bertani R Kiss T Venzo A Casarin M Benetollo F Ganis P Favretto D;Solution Solid-State Study 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(5):1281-1290
The Al(III)-binding abilities of two aldaric acids, D-saccharic acid and mucic acid (the neutral form is denoted as H(2)L), were studied in solution by means of pH potentiometric, (1)H and (13)C NMR, and ESI-MS techniques. The most probable conformations and isomeric binding modes of the complexes formed in solution were determined by density functional theory (DFT) calculations. A solid D-saccharic acid complex K(2)[[Al(LH(-2))(H(2)O)](2)].H(2)O was isolated and crystallographically characterised. The two alcoholic hydroxy groups alpha to the terminal COO(-) groups were found to take part in the coordination, but in different ways. One of them coordinates in a bridging mode. Detailed ESI-MS and NMR studies proved that the complex retains its structure in solution. However, depending on the ligand and the pH, such complexes may exist in two isomeric forms. DFT calculations on the ion [[Al(LH(-2))(H(2)O)](2)](2-) revealed that several orbitals participate in stabilizing the dimeric arrangement. 相似文献
40.
Group M. Melguizo A. Marchal M. Nogueras A. Snchez J. N. Low 《Journal of heterocyclic chemistry》2002,39(1):97-103
The nucleophilic substitution of 2‐mefhoxy groups in pyrimidine derivatives was strongly activated by introduction of a 5‐nitroso group on to the pyrimidine ring. The aminolysis of several 2‐methoxy‐5‐nitrosopyrimidine derivatives was performed at room temperature in hydroxylic as well as in non‐hydroxylic media with different primary amines in short time and good yields. The aminolysed substrates include 6‐[(per‐O‐acetyl)glycosyl]aminopyrimidines which afforded the corresponding 2‐aminopyrimidines without harming the acetyl protecting groups of the sugar moiety. 相似文献