Home – Home – Jornals – Advanced Search

We analyze recent crustal movements, based on data of GPS measurements on the Amurian Plate and its margins. Most of the velocities were borrowed from scientific publications. Also, our new and updated data of periodic and permanent GPS observations are presented. A continuous field of strain rates has been constructed using the combined field of movement velocities. Dilation rates and the directions and values of the main strain axes have been calculated. We have made a quantitative estimation of the maximum shear rates and their directions. Zones of background deformations in the inner part of the Amurian Plate have been revealed along with high-strain zones. Zones with intense tectonic activity, corresponding to areas of reduced lithosphere, often show manifestations of Late Cenozoic volcanism. Part of them can be interpreted as the present-day boundaries of intracontinental geoblocks and small lithospheric plates.

Source parameters of local earthquakes that occurred between 1998 and 2012 within the Kyrgyz seismological network (KNET) are used to study the patterns of stress drop in the Northern Tien Shan. The dynamic parameters of source radius r , the seismic moment M ₀, and the stress drop Δσ are estimated for eighty seven M = 3.0-5.5 ( K = 9.5-13.7) events, which make up 86 % of earthquakes with this magnitude (99) for the period of observations. Earthquake mechanisms are determined either from P -wave arrivals (66 events) or by inversion (14 events). The distribution of earthquake mechanisms with the maximum (14 events) and minimum (14 events) stress drop shows that the amount of released stress correlates with slip geometry and revere-slip events contribute the most into the stress drop in the area. The spatial distribution of events with Δσ > 0.9 MPa is compared with maps of kinematic parameters (Lodé-Nadaì coefficient or stress ratio, μσ, and stress-strain line slope, ω) based on average strain tensors according to the complete earthquake catalog for the Northern Tien Shan (1056 events for 1998-2012). The two sets of source parameters ( r , M ₀, Δσ and μσ, ω) correlate within the eastern Kyrgyz Range and the Karamoinok and Syndyk ranges.

We describe the development of activity at the Siberian Center for Synchrotron and Terahertz Radiation at Budker Institute of Nuclear Physics (BINP), SB RAS, since 1974, when the history of experiments with synchrotron radiation (SR) in the world was just beginning - there were no dedicated sources of radiation and works can be carried out at several nuclear centers in the world. BINP made a significant contribution to the development of synchrotron radiation sources, and SB RAS institutes did their part for development of SR application to problems of chemistry, catalysis, biology, geology and materials science. The experiments were made at VEPP-3/VEPP-4 installation.

The potent equipment of the shared-use center “Siberian Synchrotron and Terahertz Radiation Center” at Budker Institute of Nuclear Physics of the Siberian Branch of the Russian Academy of Sciences (BINP SB RAS) enables conduction of time-resolved X-ray diffraction experiments using synchrotron radiation of the VEPP-3/VEPP-4 storage rings. These experiments are performed mostly for institutions of the Siberian Branch of the Russian Academy of Sciences (SB RAS). The experiments yielded novel techniques, which have been implemented for investigation into the dynamics of the nucleation and formation of nanoparticles under explosion and shock wave impact with a nanosecond-scale time resolution (the X-ray exposure time is 73 ps), dynamics of structural transformations in chemical reactions, and kinetics of chemical reactions during gasless combustion (SHS) with a millisecond-scale time resolution, obtaining structural information about the state of catalysts and so on.

Residual stresses in rolled tungsten after pulsed irradiation with a plasma and an electron beam at the GOL-3 facility were measured. The mechanical stresses were derived from the strain, which was measured by the change in the interplanar distance in different directions. The interplanar distance was gaged from the shift of the peak of diffraction scattering of X-rays. The measured tension turned out to be a tensile stress along the surface. The tension along the direction of rolling and grinding was approximately three times larger than that in the perpendicular direction. The work was carried out at the VEPP-3/VEPP-4 complex.

Modernization of the experimental station mounted on the beamline No.2 of VEPP-3 synchrotron radiation electron storage ring at Siberian Synchrotron and Terahertz Radiation Center and intended for X-ray diffraction studies of the structure and phase composition of functional materials with high angular resolution and the possibility of using the effect of resonance scattering has been done. In operating mode the diffractometer of the beamline is equipped with a perfect flat analyzer crystal Ge (111), located in front of the detector. XRD patterns can be obtained in the range of photon energies from 7 to 18 keV (or wavelength range ~0.18 ÷ 0.07 nm). The angular range of the X-ray registration is limited to 2θ = 140 °.

The brief review has been presented about the application of X-ray fluorescent analysis using synchrotron radiation (storage ring VEPP-3, BINP SB RAS) for determination of elemental composition of the samples of different nature - biological and geological samples, objects of environment, archeological objects, and new materials. The feature of the presented research is the employment of the unique properties of synchrotron radiation, which allow analyzing samples of small mass (of the order of several milligrams), and also scanning core of bottom sediments with high resolution (less than 1 mm) that is not practical to realize by traditional analysis methods.

The study of the electronic structure of H₂Pc was carried out to examine the structure of the lowest unoccupied molecular orbitals (LUMO) of molecule phthalocyanine by X-ray absorption spectroscopy using quantum-chemical calculations. The theoretical calculations were performed on the stationary theory (frozen orbital approximation, Z +1 model) and time-dependent density functional theory (TDDFT). A consideration of K -edges absorption spectra of carbon and nitrogen in the common scale of binding energies allows estimating the contributions of AO of all phthalocyanine atoms to the LUMO, defining the sequence of levels, the binding energies of the corresponding levels, and also the character of electronic interactions between individual atoms. It was shown that the best agreement between the experimental and theoretical pre-edge structures of the absorption spectra of nitrogen and carbon for H₂Pc is observed in the case of the application of stationary density functional theory in Z +1 model to account for an X-ray hole. In this case the 2 p _p AO of the Na_(1,2) and Сa atoms make a predominant contribution to the LUMO. The 2 p _p AO of the Na _(1,2) atoms mainly contribute to the boundary LUMO with the energy ~ -2.3 eV.

Cu(II) acetate-bipyridine complex has been synthesized. A series of experimental and theoretical spectroscopic studies was carried out for the freshly prepared sample. The local atomic and electronic structure was theoretically analyzed based on functional density theory and the structural models of the complex was obtained for various solvents. IR and XANES spectra were experimentally measured and modelled in the framework of functional density theory in a generalized gradient approximation to provide information on the chemical bond and local surroundings of copper. The powder X-ray pattern of the Cu(II) complex was obtained. The measured ESR spectra of the acetate-bipyridine complex at room temperature for the solid sample and solution in DMF confirms the formation of the mononuclear square planar complex.

In the work X-ray K-edges of chromium dichalcogenides (M = V, Fe; x = 0-0.40) and MCrX₂ (M = Cu, Ag, Na; X = O, S, Se) were studied experimentally and theoretically. Comparison of fine structures of experimental XANES spectra obtained using a synchrotron radiation source and theoretical absorption spectra modelled using FDMNES software package allows one to study the influence of types of intercalate M, chalcogene X and also the effect of the cation substitution of chromium atoms by vanadium and iron on XANES structure of K-edges in and MCrX₂.