Nonlinear Deformation of Structure Elementsfrom Different Materials under Impulse and Shock Loads

simulation of high-rate deformation processes, three-dimensional models are used. The following determined relationships are taken into account: elastic-plastic deformation (according to the theory of dynamic plastic deformation); the dynamic properties of the materials, which change during deformation; the finite displacements and deformations. The problem is solved by the finite elements method. The paper analyzes the impact of pulse and shock loads performed on the elements of various constructions made of different materials. Comparison of the research results shows that the elements from the improved composite material possess both the required strength and lowest weight. Furthermore, the experimental and numerical results are compared as an example of the influence of the impulse load on the composite material plate with a cut. The paper shows the features of the distribution and localization of the stress intensity and displacements at the impulse and impact loading in the multi-layered structural elements. The deformation processes occur in different stages up to the elastic-plastic finite deformations depending on the speed of the projectile. The results of these studies were used in the analysis of the dynamic strength of real structural elements

Evidence for microplastics contamination of the remote tributary of the Yenisei River, Siberia - The pilot study results

This study is a pioneering attempt to count microplastics (MPs) in the Yenisei River system to clarify the role of Siberian Rivers in the transport of MPs to the Arctic Ocean. The average MPs content in the surface water of the Yenisei large tributary, the Nizhnyaya Tunguska River, varied from 1.20 ± 0.70 to 4.53 ± 2.04 items/m3, tending to increase along the watercourse (p < 0.05). Concentrations of MPs in bottom sediments of the two rivers were 235 ± 83.0 to 543 ± 94.1 with no tendency of downstream increasing. Linear association (r = 0.952) between average organic matter content and average counts of MPs in bottom sediments occurred. Presumably MPs originated from the daily activities of the in-situ population. Further spatial-temporal studies are needed to estimate the riverine MPs fluxes into the Eurasian Arctic seas

Mathematical modeling of thermal effectiveness of a ternary combined cycle plant

The urgency of this work is determined by the intensification of the role of steam-gas technologies (combined cycle technologies) in the field of power engineering in Russia and throughout the world. Developed mathematical model of ternary combined cycle plants, which is based on balance method includes system of mass balance and energy balance equations for ternary combined cycle plants and its units, equations of steam expansion in turbine and working fluids thermodynamic properties. On the basis of a model was carried out the analysis of the impact of the structure and thermodynamic parameters on thermal effectiveness of heat-recovery ternary combined cycle plants which cycle is the combination of three working substance cycles, one of which is low-boiling substance. The analysis of the thermal effectiveness of ternary combined cycle plants was made by means of the small-deflection method. The optimal parameters of operating environment and structure of a ternary combined cycle plants were determined

An evaporation-based model of thermal neutron induced ternary fission of plutonium

Ternary fission probabilities for thermal neutron induced fission of plutonium are analyzed within the framework of an evaporation-based model where the complexity of time-varying potentials, associated with the neck collapse, are included in a simplistic fashion. If the nuclear temperature at scission and the fission-neck-collapse time are assumed to be ~1.2 MeV and ~10^-22 s, respectively, then calculated relative probabilities of ternary-fission light-charged-particle emission follow the trends seen in the experimental data. The ability of this model to reproduce ternary fission probabilities spanning seven orders of magnitude for a wide range of light-particle charges and masses implies that ternary fission is caused by the coupling of an evaporation-like process with the rapid re-arrangement of the nuclear fluid following scission.Comment: 25 pages, 12 figures, accepted for publication in IJMP

Preliminary screening for microplastic concentrations in the surface water of the Ob and Tom Rivers in Siberia, Russia

This study characterizes the abundance and morphology of microplastics in surface water of the Ob River and its large tributary, the Tom River, in western Siberia. The average number of particles for two rivers ranged from 44.2 to 51.2 items per m3 or from 79.4 to 87.5 μg per m3 in the Tom River and in the Ob River, correspondingly. 93.5% of recovered microplastics were less than 1 mm in their largest dimension, the largest group (45.5% of total counts) consisted of particles with sizes range 0.30-1.00 mm

Hydrobionts of a freshwater oil-polluted northern lake: bioaccumulation of heavy metals in fish and the rate of ecosystem recovery

The response of phytoplankton, zooplankton, benthic and fish community structure to one of the biggest oil spill in history of Komi Republic (north-west part of Russia) was investigated using data from a long-term survey off the polluted lake. The characteristics of aquatic freshwater communities observed in the study area 10, 11 and 22 years after the spill (1994) were compared to find out the rate of natural recovery of the ecosystem after oil decontamination of bottom sediments. The concentrations of fifteen trace metals (Al, Cr, Fe, Co, Ni, Cu, Zn, As, Mo, Cd, Sb, Pb, U, Bi, Th) were analyzed in the tissues (muscle) of three fish species. The concentrations of Al (3-309 mg/kg), Cr (0,1-3,71 mg/kg), Fe (8,6-317 mg/kg), and Cu (0,09-99 mg/kg) in fishes from polluted lake resulted in most cases higher than reference thresholds. Quantitative and qualitative indicators of aquatic invertebrates from polluted lake reach those one of unpolluted lake but do not fully recover 22 years after the spill, despite that oil concentration in water column and in bottom sediments was lower than reference tresholds. We conclude that natural recovery rate of aquatic freshwater ecosystems in northern regions after oil pollution is extremely low. The purification of water and bottom sediments of oil-polluted northern water bodies is necessary for stimulation of ecosystem restoration

Oxidative detoxification of organomercury pesticides

A method of oxidative mineralization of the organomercury granozan pesticide commercial form under mild conditions was investigated. The product components of hazard class 1 were destructed to the low-toxic compounds in the electrolyte under the oxidants electrochemically formed in situ in sulphuric acid solutions of pesticide. Simultaneously, at the cathode, the mercury ions formed as a result of the pesticide organic component destruction process reduce up to more than 90%

Status and perspective of detector databases in the CMS experiment at the LHC

This note gives an overview at a high conceptual level of the various databases that capture the information concerning the CMS detector. The detector domain has been split up into four, partly overlapping parts that cover phases in the detector life cycle: construction, integration, configuration and condition, and a geometry part that is common to all phases. The discussion addresses the specific content and usage of each part, and further requirements, dependencies and interfaces