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991.
We apply methods of quantum mechanics for mathematical modeling of price dynamics at the financial market. The Hamiltonian formalism on the price/price-change phase space describes the classical-like evolution of prices. This classical dynamics of prices is determined by “hard” conditions (natural resources, industrial production, services and so on). These conditions are mathematically described by the classical financial potential V(q),V(q), where q=(q1,…,qn)q=(q1,,qn) is the vector of prices of various shares. But the information exchange and market psychology play important (and sometimes determining) role in price dynamics. We propose to describe such behavioral financial factors by using the pilot wave (Bohmian) model of quantum mechanics. The theory of financial behavioral waves takes into account the market psychology. The real trajectories of prices are determined (through the financial analogue of the second Newton law) by two financial potentials: classical-like V(q)V(q) (“hard” market conditions) and quantum-like U(q)U(q) (behavioral market conditions).  相似文献   
992.
In bilayer graphene, mutual rotation of layers has strong effect on the electronic structure. We theoretically study the distribution of electron density in twisted bilayer graphene with the rotation angle of 21.8° and find that regions with AA‐like and AB‐like stacking patterns separately contribute to the interlayer low‐energy van Hove singularities. In order to investigate the peculiarities of interlayer coupling, the charge density map between the layers is examined. The presented results reveal localization of π‐electrons between carbon atoms belonging to different graphene layers when they have AA‐like stacking environment, while the interlayer coupling is stronger within AB‐stacked regions.

Charge density map for bilayer graphene with a layer twist of 21.8° (interlayer region).  相似文献   

993.
The vibrational dynamics of elemental solids that form incommensurate host-guest structures are of fundamental interest. High-pressure Raman scattering has been used to examine the vibrational spectrum of the group-V element Sb up to 33 GPa. A1g and Eg phonons of the ambient pressure rhombohedral A7 phase display a marked decrease with pressure, i.e., prior to the transition to the tetragonal host-guest Sb-II phase at 8.6 GPa, via the monoclinic host-guest Sb-IV phase. The Raman spectrum of the incommensurate host-guest Sb-II phase, has five bands between 80 cm−1 and 200 cm−1 that increase with pressure. For the bcc structure stable above 28 GPa, we observe one weak disorder-induced band that increases with pressure.  相似文献   
994.
995.
The three-component condensation reaction of primary amines, formaldehyde and 2-mercaptoethanol using salts of transition and rare earth metals as catalysts was developed to obtain a new 7-membered heterocyclic structural building block, 1,5,3-oxathiazepanes, in good to excellent yields. The structure of the heterocyclic fragment was confirmed by NMR spectroscopy.  相似文献   
996.
997.
998.
The title compound, prepared from C(60) and CF(3)I at 500 degrees C, exhibits an unusual fullerene(X)12 addition pattern that is 40 kJ mol(-1) less stable than the previously reported C(60)(CF(3))12 isomer.  相似文献   
999.
In this work, we review the hyperpolarization technique named chemically induced dynamic nuclear polarization (CIDNP), focusing on the time-resolved variant of this method and its biological applications. We introduce the main principles of polarization formation in liquids at high magnetic fields, provided by the so-called spin sorting mechanism. Applications of CIDNP to studying fast reactions of short-lived free radicals of biologically important molecules are discussed, as well as the potential of the method to probe the structure and magnetic parameters of such radicals. We also explain the principles of protein CIDNP and discuss applications of time-resolved CIDNP to studies of protein structure and dynamics.  相似文献   
1000.
Chemistry of Heterocyclic Compounds - Microreview focuses on the main modern synthetic approaches toward 2-azaanthracene and its derivatives. These approaches are: inverse electron-demand...  相似文献   
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