Dynamics of moving interacting atoms in a laser radiation field and optical size resonances

The forces acting on interacting moving atoms exposed to resonant laser radiation are calculated. It is shown that the forces acting on the atoms include the radiation pressure forces as well as the external and internal bias forces. The dependences of the forces on the atomic spacing, polarization, and laser radiation frequency are given. It is found that the internal bias force associated with the interaction of atomic dipoles via the reemitted field may play an important role in the dynamics of dense atomic ensembles in a light field. It is shown that optical size resonances appear in the system of interacting atoms at frequencies differing substantially from transition frequencies in the spectrum of atoms. It is noted that optical size resonances as well as the Doppler frequency shift in the spectrum of interacting atoms play a significant role in the processes of laser-radiation-controlled motion of the atoms.     

Experimental investigation of highly excited states of the 5,6He and 5,6Li nuclei in the (6Li, 7Be) and (6Li, 7Li) one-nucleon pickup reactions

The (⁶Li, ⁷Be) and (⁶Li, ⁷Li) reactions on ⁶Li and ⁷Li nuclei were investigated in the angular interval 0°–20° in the laboratory system at a ⁶Li energy of 93 MeV. In addition to low-lying states of the ^5,6He and ^5,6Li nuclei, broad structures were observed near the t(³He)+d and t(³He)+t thresholds at the excitation energies of 16.75 (3/2⁺) and ～20 MeV (for ⁵He), 16.66 (3/2⁺) and ～20 MeV (⁵Li), 14.0 and 25 MeV (⁶He), and ～20 MeV (⁶Li). The angular distributions measured in the ⁷Li(⁶Li, ⁷Be)⁶He reaction for transitions to the ground state (0⁺) and excited states at E _x=1.8 MeV (2⁺) and 14.0 MeV of the ⁶He nucleus were analyzed by the finite-range distorted-wave method assuming the 1p-and 1s-proton pickup mechanism. The (⁶Li, ⁷Be) and (⁶Li, ⁷Li) reactions were shown to proceed predominantly through the one-step pickup mechanism, and the broad structures observed at high excitation energies are considered as quasimolecular states of the t(³He)+d and t(³He)+t types.     

Influence of the structure of the organoaluminum compound on the stereoregulating heterogeneity of catalytic systems based on TiCl4

The stereoregulating heterogeneity manifested in butadiene polymerization by active sites of the titanium catalytic system formed “separately” in combination with organoaluminum ligands was examined.     

The Integrative Approach to Study of the Structure and Functions of Cardiac Voltage-Dependent Ion Channels

Crystallography Reports - Membrane proteins, including ion channels, became the focus of structural proteomics midway through the 20th century. Methods for studying ion channels are diverse and...     

Average stationary binary-mixture convection in connected channels in the presence of high-frequency vibration

The effect of vertical high-frequency vibration on steady-state binary-mixture flows in connected channels is studied theoretically. Mixtures with both positive and negative thermal diffusion are considered. It is shown that the convection excitation mode changes with the sign of the thermal diffusion. The dependence of the flow amplitude on the supercriticality is analytically obtained for various vibrational Rayleigh numbers.     

Determination of enantiomeric purity of 1-substituted 3-amino-1,2-dicarba-<Emphasis Type="Italic">closo</Emphasis>-dodecaboranes by HPLC on chiral stationary phases

A determination of enantiomeric purity of 1-substituted (Me, Ph, and Prⁱ) 3-amino-1,2dicarba-closo-dodecaboranes by HPLC on chiral Chiralcel OD-H and Chiralpac AD stationary phases involving preliminary phthaloylation of 3-aminocarboranes has been suggested as a general method.     

Solvent effect on molecular characteristics of polybutadiene and on the kinetic heterogeneity of catalytic systems based on TiCl4

Solvent effect on the molecular characteristics of polybutadiene and on the kinetic heterogeneity of catalytic systems based on TiCl₄ was studied.     

A spectroscopic and computational study of Al(III) complexes in sodium cryolite melts: Ionic composition in a wide range of cryolite ratios

The structure of sodium cryolite melts was studied using Raman spectroscopy and quantum chemical calculations performed at the density functional theory level. The existence of bridged forms in the melts was argued first from the analysis of experimental Raman spectra. In the quantum chemical modelling emphasis was put on the construction of potential energy surfaces describing the formation/dissociation of certain complex species. Effects of the ionic environment were found to play a crucial role in the energetics of model processes. The structure of the simplest possible polymeric forms involving two Al centres linked through F atoms (“dimers”) was thoroughly investigated. The calculated equilibrium constants and model Raman spectra yield additional evidence in favour of the dimers. This agrees with a self-consistent analysis of a series of Raman spectra for a wide range of the melt composition.