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Due to the large size of light-harvesting complexes, approximate methods are commonly used for calculating the coupling energies between their constituents. Two approximate methods are studied in this work: TrESP and the recently suggested TrCAMM method, based on the expansion of the one-particle density matrix. The quality of approximation of the electrostatic potential in the framework of these two approaches has been compared for two biological pigments as an example—chlorophyll a and bacteriochlorophyll a. It has been shown that both approaches provide high accuracy of approximation of the matrix elements of the electrostatic potential operator. In addition, it has been demonstrated that symmetrization of the one-particle density matrix in the framework of the TrCAMM method significantly improves the calculation accuracy and makes the computational procedure unambiguous. 相似文献
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N. P. Belov S. N. Lapshov E. E. Mayorov A. S. Sherstobitova A. D. Yaskov 《Journal of Applied Spectroscopy》2012,79(3):499-502
Measurements of the refractive index, its temperature dependence, and the optical transmission of black liquors produced during sulfate pulping are reported for soluble solid residue concentrations up to k ≅ 60 %. The design features of a commercial refractometer for monitoring the concentration of black liquor are examined briefly. A procedure is proposed for laboratory calibration of commercial sensors that employs black liquor solutions in highly refractive organic liquids as reference samples. 相似文献
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M. V. Koldaeva V. I. Alshits E. A. Petrzhik E. V. Darinskaya A. Yu. Belov 《Bulletin of the Russian Academy of Sciences: Physics》2014,78(10):1086-1091
It is shown that the criterion of dislocation mobility resonance in NaCl crystals in the electron spin resonance scheme in the Earth’s magnetic field depends on both the sample orientation in this field and the location of impurity atoms in the dislocation core. The measured low-frequency spectrum of dislocation paths makes it possible to resolve a series of peaks corresponding to different positions of a Ca impurity that correlate with the results from computer simulations of the dislocation core structure. 相似文献
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D. V. Permyakov I. S. Mukhin I. I. Shishkin A. K. Samusev P. A. Belov Yu. S. Kivshar 《JETP Letters》2014,99(11):622-626
We study, both experimentally and theoretically, the scattering of electromagnetic waves by a subwavelength hole fabricated in a thin metallic film. We employ the scanning near-field optical microscopy in order to reconstruct experimentally the full three-dimensional structure of the electromagnetic fields in the vicinity of the hole. We observe an interference of all excited waves with an incident laser beam which allows us to gain the information about the wave phases. Along with the well-known surface plasmon polaritons propagating primarily in the direction of the incident beam polarization, we observe the free-space radiation diffracted by the hole. We compare the experimental results with the fields of pure electric and pure magnetic dipoles as well as with direct numerical simulations. We confirm that a single hole in a thin metallic film excited at the normal incidence manifests itself as an effective magnetic dipole in the visible spectral range. 相似文献
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N. M. Aristova G. V. Belov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2014,88(9):1445-1449
Data on the thermodynamic properties of cerium mononitride CeN in the solid state are analyzed. Relations approximating the temperature dependence of the thermodynamic functions of CeN(cr.) in the temperature range of 298.15–2900 K are obtained. Using the relations of thermodynamics known for this temperature range, the thermodynamic functions of cerium mononitride (entropy, Gibbs energy, and enthalpy variation) are calculated. The resulting data is entered into the database of the IVTANTHERMO software package and is used to analyze the thermal stability of CeN(cr.), and to estimate its boiling point at atmospheric pressure. 相似文献
29.
It is shown that for Mindlin media with fields of defects there is an alternative interpretation allowing to describe the material affected by defects as equivalent functionally-gradient material with varying properties for coordinates, modeled in the classical theory of elasticity. We establish clear relationships for determining the properties of functionally graded materials by the solutions, taking into account the availability of fields of defects. It is shown that, in general, the properties of equivalent functionally-gradient material depend on the coordinates, as well as on the loading and boundary conditions. 相似文献
30.
Kozhemyakin G. N. Belov Y. S. Artemov V. V. Trufanova M. K. Volchkov I. S. 《Crystallography Reports》2022,67(3):441-446
Crystallography Reports - Tellurium (Te) nanostructures have been obtained on glassy carbon substrates by thermal evaporation in an argon atmosphere. The sizes and shape of Te particles have been... 相似文献