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121.
S. Qi H. Behringer T. Raasch F. Schmid 《The European physical journal. Special topics》2016,225(8-9):1527-1549
We discuss in detail a recently proposed hybrid particle-continuum scheme for complex fluids and evaluate it at the example of a confined homopolymer solution in slit geometry. The hybrid scheme treats polymer chains near the impenetrable walls as particles keeping the configuration details, and chains in the bulk region as continuous density fields. Polymers can switch resolutions on the fly, controlled by an inhomogeneous tuning function. By properly choosing the tuning function, the representation of the system can be adjusted to reach an optimal balance between physical accuracy and computational efficiency. The hybrid simulation reproduces the results of a reference particle simulation and is significantly faster (about a factor of 3.5 in our application example). 相似文献
122.
Daniel S. Covita Dimitrios F. Anagnostopoulos Hermann Fuhrmann Hubert Gorke Detlev Gotta Alexander Gruber Albert Hirtl Tomoichi Ishiwatari Paul Indelicato Thomas S. Jensen Eric-Olivier Le Bigot Valeri E. Markushin Michael Nekipelov Vladimir N. Pomerantsev Vladimir P. Popov Joaquim M. F. dos Santos Philipp Schmid Leopold M. Simons Marian Theisen Martino Trassinelli Joao F. C. A. Veloso Johann Zmeskal 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2018,72(4):72
123.
Dr. Todor Baramov Bianca Schmid Ho Ryu Jinhoon Jeong Dr. Karlijn Keijzer Dr. Leonard von Eckardstein Prof. Dr. Mu-Hyun Baik Prof. Dr. Roderich D. Süssmuth 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(28):6955-6962
The E. coli siderophore enterobactin, the strongest FeIII chelator known to date, forms hexacoordinate complexes with SiIV, GeIV, and TiIV. Synthetic protocols have been developed to prepare non-symmetric enterobactin analogues with varying denticities. Various benzoic acid residues were coupled to the macrocyclic lactone to afford a diverse library of ligands. These enterobactin analogues were bound to SiIV, GeIV, and TiIV, and the complexes were investigated through experimental and computational techniques. The binding behavior of the synthesized chelators enabled assessment of the contribution of each of the phenolic hydroxy groups in enterobactin to metal-ion complexation. It was found that at least four O-donors are needed for enterobactin derivatives to act as metal binders. Density functional theory calculations indicate that the strong binding behavior of enterobactin can be ascribed to a diminished translational entropy penalty, a common feature of the chelate effect, coupled with the structural arrangement of the three catechol moieties, which allows the triseryl base to be installed without distorting the preferred local metal-binding geometry of the catecholate ligands. 相似文献
124.
Schmid MC Oeltermann A Juchem C Logothetis NK Smirnakis SM 《Magnetic resonance imaging》2006,24(4):335-342
Simultaneous electroencephalography (EEG)/functional magnetic resonance imaging (fMRI) acquisition can identify the brain networks involved in generating specific EEG patterns. Yet, the combination of these methodologies is hampered by strong artifacts that arise due to electromagnetic interference during magnetic resonance (MR) image acquisition. Here, we report corrections of the gradient-induced artifact in phantom measurements and in experiments with an awake behaving macaque monkey during fMRI acquisition at a magnetic field strength of 4.7 T. Ninety-one percent of the amplitude of a 10 microV, 10 Hz phantom signal could successfully be recovered without phase distortions. Using this method, we were able to extract the monkey EEG from scalp recordings obtained during MR image acquisition. Visual evoked potentials could also be reliably identified. In conclusion, simultaneous EEG/fMRI acquisition is feasible in the macaque monkey preparation at 4.7 T and holds promise for investigating the neural processes that give rise to particular EEG patterns. 相似文献
125.
The recently proposed fish bone optical model is tested on0α-16 O scattering. Using a microscopic interaction similar to that of resonating group calculations the characteristic rotational bands in20Ne as well as the gross structure of the elastic differential cross section are reproduced. It is shown that the fish bone optical model can be extended by inclusion of a phenomenological imaginary part. A numerical comparison with the corresponding double folding model and with the Saito model confirms the theoretical prediction that the fish bone optical model is a further step towards inclusion of the effect of the Pauli principle in the optical model. 相似文献
126.
127.
C. Haefeli M.A. Ivanov M. Schmid 《The European Physical Journal C - Particles and Fields》2008,53(4):549-557
We investigate three-flavour chiral perturbation theory including virtual photons in the limit in which the strange quark
mass is much larger than the external momenta and the up and down quark masses, and where the external fields are those of
two-flavour chiral perturbation theory. In particular, we work out the strange quark mass dependence of the electromagnetic
two-flavour low-energy constants C and ki. We expect that these relations will be useful for a more precise determination of the electromagnetic low-energy constants.
PACS 11.30.Rd; 12.39.Fe; 13.40.Dk; 13.40.Ks 相似文献
128.
A. S. Kuznetsov R. W. E. van de Kruijs M. A. Gleeson K. Schmid F. Bijkerk 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2010,4(4):563-566
Mo/Si multilayer mirrors were exposed to deuterium ions with well-defined energies in order to gain insight into the effects
of Extreme UV light driven plasma generation on reflective elements in commercial lithography equipment. Post-irradiation
analysis by Rutherford Backscattering Spectrometry showed erosion of both Mo and Si layers for the highest energy 50 eV/D
and exposure time 5.4 × 104 s. Nuclear Reaction Analysis revealed detectable deuterium retention for energies ⩾25 eV/D. Surface analysis by X-ray Photoelectron
Spectroscopy showed erosion of the first Si layer for energies ⩾5 eV/D. Inferences on the spatial distribution of trapped
deuterium are made on the basis of available data regarding deuterium retention in the materials in question. 相似文献
129.
W. Fuß J. Göthel K. L. Kompa M. Ivanenko W. E. Schmid 《Applied physics. B, Lasers and optics》1992,55(1):65-70
A low-pressure (20 mbar) CO2 laser allows to extract pulses at several selected wavelengths simultaneously from the same active medium. We demonstrated this, using an industrial laser modified by a Q-switch and a resonator with two branches. In one branch the wavelengths are spatially separated, whereas in the other they oscillate in one common transverse mode. We designed a multi-wavelength resonator which requires a single additional reflector compared to usual laser cavities. It provided tunable oscillation at six wavelength simultaneously. 相似文献
130.