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The results of physical and mathematical modelling in the ANSYS software package of three-dimensional unsteady coupled heat and mass transfer in the previously developed diamond vacuum window (DVW) of the workstation of the Siberian Circular Photon Source under construction are presented. Previous simulations have convincingly shown: the possibility of using a mini-channel cooling system to implement reliable and proper temperature management of this optical device, the advantage of a mini-channel cooling system over a one channel system in terms of fulfilling the optical requirements for DVW and its design. Here are detailed calculations of unsteady three-dimensional flow in the mini-channels of the cooling system, which will prevent possible dramatic destruction of the workstation due to local overheating of the CVD-diamond foil and its recrystallization. [ABSTRACT FROM AUTHOR]

Chemical analysis of samples of ovarian fluid (OF), a secondary product of breeding of the two common species of Acipenseridae family in Russian aquaculture, was carried out in order to assess its nutritional and possible medicinal value. It has been established that the dominant organic component of OF of both species is a water-soluble or water-dispersible protein easily absorbed by the digestive tract. Proteomic analysis of the samples has shown that the main component of the protein fraction of OF is a highly nutritious protein vitellogenin. Amino acid analysis has shown that 350 g of dried sturgeon OF or 245 g of dried sterlet OF satisfy the needs of an adult human in all essential amino acids per one day. Eighty-five grams of dried sturgeon OF or 55 g of dried sterlet OF covers the daily requirement of an adult for vitamins C, B1, B2, B3 (PP) and B6, a number of macroelements (Na, K, Ca, Mg) and microelements (Fe, Cu, Mn, Zn, Cr). Furthermore, Cu content is significantly higher in sturgeon OF, and Fe content is significantly higher in sterlet OF, which is partly confirmed by the relative content of Cu and Fe carrier proteins, ceruloplasmin and transferrin, respectively. In addition, a number of proteins of physiological significance for fish were identified. The possible medicinal value of OF consists, among other things, in significant content of various antioxidant proteins in OF of both species. The use of OF as a food supplement could improve the profitability of sturgeon breeding by producing an additional valuable product, and would also expand the range of natural dietary supplements on the market. [ABSTRACT FROM AUTHOR]

The SKIF Synchrotron and Terahertz Radiation Center provides users from various organizations with access to modern analytical techniques using synchrotron radiation beams for a wide range of research work. The general direction in developing the Center is now focused on generating new approaches to using synchrotron radiation. [ABSTRACT FROM AUTHOR]

The project of the station of synchrotron radiation of the second stage Plamya-2 for the Siberian ring photon source SKIF is based on the experience gained during the development of the station "Plamya" on the storage ring VÉPP-4 at the Siberian Center for Synchrotron Radiation (SR). The station is designed to study the processes of combustion and thermal decomposition of various organic compounds by the method of photoionization mass spectrometry using vacuum ultraviolet (VUV) synchrotron radiation. The use of selective photoionization by VUV radiation in the molecular beam method of sampling from the reaction zone in flames or pyrolyzers makes it possible to identify and quantify the concentrations of atoms, radicals, and other labile and short-lived compounds, which provides key information on chemical transformations under conditions of high-speed combustion and thermal decomposition. The paper considers the possibility of using various SR generators available on the SKIF storage ring, as well as the optical scheme of the station and the conceptual design of its front-end. The experimental results of measuring photon fluxes for the Plamya station and the calculated photon fluxes on the sample for the Plamya-2 station are also presented. [ABSTRACT FROM AUTHOR]

The main technical solutions chosen to implement the project of fourth-generation synchrotron radiation (SR) source Synchrotron Radiation Facility "Siberian Circular Photon Source" (SRF SKIF), which is currently being built in Novosibirsk, are presented. The choice of the configuration and parameters of the synchrotron radiation source is described; the principles of the scientific program compilation are considered; and the radiation generation devices, the frontend design, and the engineering infrastructure are discussed. [ABSTRACT FROM AUTHOR]

The Siberian ring source of photons (SKIF) is a new 3-GeV fourth-generation source of synchrotron radiation with a perimeter of 480 m that is being developed in Novosibirsk. To obtain bright synchrotron-radiation beams, the SKIF must have a suitable injection system for the preparation of intense electron beams. The article describes the proposed configuration of the injection system and its parameters. Electron bunches are produced by a thermal gun based on a radio frequency cavity. Then they are accelerated to 200 MeV in a linac and accelerated to 3 GeV in a booster synchrotron with a perimeter of 160 m. The injection complex will operate at a frequency of 1 Hz and will be able to pump the main storage ring with a current of up to 400 mA in one minute. [ABSTRACT FROM AUTHOR]

The determination of the carnosine level in fish muscle tissues is helpful for the purposes of general biology and comparative muscle physiology of various fish species; it may be also useful for estimation of the nutritional value of fish products. The mass-spectrometric method of the determination of carnosine in muscle tissues has been improved and tested in this work. The carnosine levels in the muscles of the Russian sturgeon, Siberian sturgeon, sterlet, hybrid of sterlet and kaluga, hybrid of Siberian sturgeon and kaluga have been determined for the first time with this method. The starlet-and-kaluga hybrid, regardless of sex, contains 3.33 times more carnosine than the sterlet (p < 0.01). The female hybrid of Siberian sturgeon and kaluga contains 1.50 times less carnosine than the female Siberian sturgeon (p < 0.1). Since carnosine consumption is important for carnosine biosynthesis in human muscles, the hybridization of sterlet with kaluga is more efficient in terms of nutrition value than pure sterlet breeding, and the hybridization of Siberian sturgeon with kaluga is less effective than sturgeon breeding. [ABSTRACT FROM AUTHOR]

The improved spatial coherence of a synchrotron radiation beam was shown experimentally to stimulate additional diffuse scattering of x rays diffracted from x-ray multilayer mirrors. Although the large-scale (tens of microns) roughness does not affect Bragg diffraction from multilayers, its presence causes phase shifts at the wave packet front. This leads to partial decay of the coherent wave packet and creates additional diffuse scattering. Additional scattering from this mechanism was observed at angles of incidence corresponding to the Bragg and Kiessig maximum angles. The properties of this scattering caused by large-scale roughness, observed due to improved x-ray beam spatial coherence, were shown experimentally to be different from those of diffuse scattering previously reported when the incoming or outgoing angle is equal to the Bragg angle. Typical breaks in the diffuse scattering intensity due to the standing-wave effect are absent, and there is obvious asymmetry of the diffuse scattering cross section around the incoming and outgoing angles. Due to the small angle of incidence, the coherently irradiated area has very different dimensions parallel and perpendicular to the beam, which leads to the observed scattering being concentrated in the specular diffraction plane defined by the incident and reflected wave vectors. [ABSTRACT FROM AUTHOR]

The results of synchrotron-radiation experiments, carried out at the VEPP-4M electron-positron collider in a wide energy range from 10 eV to 200 keV, are presented. To increase the radiation intensity, the electron-beam energy in the VEPP-4M accelerator ring is raised from 4 to 4.5 GeV. To carry out experiments in the high-energy range of synchrotron radiation, a new multipole hybrid wiggler, producing a field of 1.9 T, is installed at the accelerator ring. A method for calibrating the energy of electrons in the accelerator using a laser polarimeter is discussed. [ABSTRACT FROM AUTHOR]

An Erratum to this paper has been published: https://doi.org/10.3103/S106287382301001X [ABSTRACT FROM AUTHOR]

Testing for substance toxicity for living organisms is an important step in the development and adaptation of new drugs for various purposes. Analysis of the dependences between toxicological parameters of chemical substances for various test objects and physicochemical properties of these agents is a promising trend. Partition coefficient logP (logK) was chosen as the key physicochemical parameter determining the toxicological parameters of the same substance for hydrobionts at different developmental stages. We found a correlation between decimal logarithm of the ratio of LC for fish embryos to LC for adult fish and logP. This dependence was found as a liner combination of equations obtained by drawing a trend line between experimental points and calculation of Pearson's correlation coefficient R. [ABSTRACT FROM AUTHOR]

We revealed empirical dependences between common logarithm of a ratio of rat oral LD to LC for adult fish and lgP for 50 different chemicals; and common logarithm of a ratio of the oral LD in rodents to LC for fish embryos and lgP for 30 different chemicals. The dependences were obtained by constructing a trend line between experimental points and calculation of Pearson's R correlation coefficient as a measure of regression significance. These dependences can show the influence of substance lipophilicity on its toxicity for aquatic organisms comparing to mammals. [ABSTRACT FROM AUTHOR]

It is planned to construct a network of national sources of synchrotron radiation with extremely low emittance in Russia in the near future, known as the SSRS-4 (Fourth Generation Specialized Source of Synchrotron Radiation program). In this work, modern and promising methods for using synchrotron radiation are described from the viewpoint of insertion devices for generating synchrotron radiation. [ABSTRACT FROM AUTHOR]

Changes of the structure and phase composition occurring during the interaction of copper and its alloys in the solid-state phase with the liquid melts of indium, gallium and tin are considered. It is shown that the phase and morphological composition of interaction products depends on the relations between the rates of diffusion and the rates of reagent dissolution. Structural transformations that take place during contact melting and eutectic crystallization in the zones of indium-tin and indium-bismuth contacts are also considered. A hypothesis concerning the nature and microstructure of eutectics is proposed. All experiments are performed on the VEPP-3/VEPP-4 storage ring. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The elemental composition of loose sediments in the Kan-i-Gut cave mine located in the foothills of the Turkestan range (Kyrgyzstan) is determined by X-ray fluorescence analysis with the use of synchrotron radiation. The samples of loose sediments are selected at different points in the cave, from the entrance to the lowest horizon. The first geochemical data on residual loose sediments in the Kan-i-Gut cave mine are obtained. They allow detailed study of the poorly studied migration of chemical elements in karstic cavities and its specific conditions, which can remain unchanged for a long time. [ABSTRACT FROM AUTHOR]

A variant of the analysis of biological tissue (standard liver specimen, NCSZC 85005 Beef liver), where its reference specimen is q standard specimen of the geological matrix (soil, IAEA Soil-7), is considered. Concentrations of elements: K, Ca, Mn, Fe, Cu, Zn, Br, Rb, and Sr in the standard liver specimen are determined with and without consideration of the absorption of fluorescence emission by different matrices. The introduction of an absorption correction makes it possible to effectively take into account the difference in the absorption properties of the matrices under investigation (liver and soil) and determine the concentrations of chemical elements, which insignificantly differ from certified data. [ABSTRACT FROM AUTHOR]

The techniques of X-ray fluorescence analysis with synchrotron radiation (SRXRF) use mainly the external standard method, which imposes an essential requirement of similarity of absorption and scattering of the primary and fluorescence radiation by the matrices of the test sample and the reference one. In this connection, there is an actual problem of shortage or absence of required standard reference samples. In this paper we consider a variant of analysis of a biological tissue (certified reference material NCSZC 85005 Beef liver) with a standard sample of geological matrix (certified reference material IAEA Soil-7) as a reference sample. The concentrations of K, Ca, Mn, Fe, Cu, Zn, Br, Rb and Sr were determined in the standard liver sample with and without allowance for fluorescence radiation absorption by the differing matrices. Using the absorption correction enabled full account of the difference in the absorption properties of the matrices under study (liver and soil) and obtaining chemical element concentrations having no significant difference from certified values. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The VEPP-4 accelerator-accumulator complex is designed for carrying out experiments with colliding electron-positron beams with the energy in the range of from 1 to 5 GeV using a VEPP-4M collider equipped with the KEDR magnetic detector. Experiments in the field of high-energy physics (HEP) using the complex in its present state have been being carried out since 2002. Science programs other than HEP programs are carried out in the VEPP-4, including experiments with synchrotron-radiation (SR) beams and studies on nuclear physics with an internal gas target, on verification of the CPT invariance, on accelerator physics, etc. The status of the complex, main results, methods used, new approaches, and long-term plans have been described. [ABSTRACT FROM AUTHOR]

The nuclear-physical characteristics obtained for a gallium target in a series of experiments using the time-of-flight method, the method of threshold indicators and a spectrometer based on a He proportional counter on the IREN setup (JINR, Dubna) are presented. The absolute values of the energy spectra of leakage neutrons in the energy range from 10 keV to 15 MeV were measured. The activation method was used to measure the neutron flux density on the surface of a gallium target: (2.882 ± 0.098) · 10 sec · cm. The integral yield of neutrons obtained from the gallium target on the basis of these data was 1.54 · 10 sec with average current 4 mA. The time dependence of the activation level of the gallium target was measured. It was shown as a result of the analysis that the background level is reached on the surface of the irradiated gallium target in 5 days. [ABSTRACT FROM AUTHOR]

new matrix of the spectra of prompt fission neutrons for the reaction U( n, F) has been obtained. The evaluated spectrum of prompt fission neutrons reproduces the measured data for incident neutrons with energy from thermal to 14.7 MeV. A solution is proposed for the problem of inconsistency of the integral testing of the systems with a thermal spectrum and differential measurements of the spectra of prompt fission neutrons. The matrix obtained for the spectra of prompt neutrons for U( n, F) eliminates the considerable discrepancy between the differential and integral experiments. The description of the integral experiments for compositions with a fast neutron spectrum revealed the compensation effect in the multiplication factor K, due to the difference in the shapes of the spectra of prompt fission neutrons, the present work and known libraries. The description of systems with a thermal neutron spectrum shows that the positive shift of the computed K is explained by the influence of the low-energy neutrons. [ABSTRACT FROM AUTHOR]

Results are given concerning the two-dimensional scanning microanalysis of microsections of metallographic specimens of rocks. The monochromatized or white SR beam from a wiggler magnet installed at the electron storage ring VEPP-3 (2 GeV, 20 kG, 100-200 mA) was used for fluorescence excitation. The working energies ranged from 8 to 35 keV. Without focusing x-ray optics, the spatial resolution was 60 μm with the monochromatic beam and 30 μm with the white SR beam. The minimum detectable concentration of the elements ( within the Fe-Sr region) is 10 ppm for 1-3 s exposures per point. [ABSTRACT FROM AUTHOR]